目的:探讨应用体外膜肺氧合(extracorporeal membrane oxygenation,ECMO)辅助治疗心脏术后难治性心室颤动(refractory ventricular fibrillation,RVF)的临床特点及病情转归,并行5年期随访,判断其应用价值和中远期疗效.方法:回顾性分析2015年1月至2017年12月,我院26例因心脏外科术中或术后24h内出现RVF,并应用静脉一动脉ECMO(venous-arterial ECMO,V-AECMO)技术进行抢救治疗的患者资料,并于2023年1月对出院患者经行电话随访,了解患者出院后生存情况和心脏功能状态.结果:26例患者中的23例行体外循环心脏外科手术,因RVF于手术室中启动ECMO治疗,由体外循环中转为ECMO,另外3例不停跳旁路移植手术(off-pump coronary artery bypass grafting,OPCABG)患者于 ICU 发生难治性心室颤动,抢救性放置ECMO;26例均采用切开方式进行股动静脉插管,平均辅助时间(111.5±50.8)h.ECMO前电除颤7.5(5.8,9.3)次,辅助后自动转复16例(61.5％),电除颤转复8例(30.8％).17例(65.4％)放置主动脉内球囊反搏(intra-aortic balloon pump,IABP),9例(34.6％)行连续性肾替代治疗(continuous renal replacement therapy,CRRT)治疗.患者术后第1日心肌酶学指标全部明显升高.本组病例数据与ELSO组织2021年公布的因心脏术后心源性休克采用ECMO治疗的多中心大样本注册研究数据进行统计对比,撤机成功率分别为88.5％(23/26)和56.4％(4 051/7 185),存活出院率分别为76.9％(20/26)和41.7％(2 997/7 185),本组病例撤机成功率和存活出院率明显高于ELSO组织的数据(P＜0.001).ICU平均住院(10.3±6.7)d,术后平均住院时间(18.4±8.0)天.失访1例,随访19例,1年存活率64.0％,5年存活率52.0％.目前存活11例,存活5.1～7.8年,NYHA心功能分级Ⅰ级1例,Ⅱ级7例,Ⅲ级3例.结论:应用ECMO技术治疗心脏术后RVF,撤机成功率和存活出院率较高,中远期生存情况良好.

AbstractAimsTo investigate the impact of intra‐aortic balloon pump (IABP) on the regional haemodynamics of patients with severe cardiogenic shock undergoing femoro‐femoral veno‐arterial extracorporeal membrane oxygenation (VA‐ECMO).Methods and resultsFrom July 2017 to April 2018, a total of 39 adult patients with cardiogenic shock receiving both IABP and ECMO for circulatory support were enrolled consecutively in a university‐affiliated cardiac surgery intensive care unit. The blood flow rates (BFRs) of the bilateral femoral artery (IABP side: iFA, ECMO side: eFA) and carotid artery (left: LCA, right: RCA) and the velocity time integral (VTI) of aortic root were assessed by ultrasonography and compared when IABP was on and off. Seventeen of 39 (43.6%) patients survived to discharge, and 29 (74.4%) survived on ECMO. A total of 172 pairs of data (IABP on and off) were collected in this study, measured on the median of 2.0 (1.0, 4.5) days after patients received VA‐ECMO. The BFR on both sides of FA (iFA: 176.4 ± 104.5 vs. 152.2 ± 139.8 mL/min, P < 0.01; eFA: 299.3 ± 279.9 vs. 242.4 ± 258.8 mL/min, P < 0.01) and the aortic VTI (10.1 ± 4.4 vs. 8.5 ± 4.4 cm, P < 0.01) decreased significantly when turning the IABP off, while the BFR on both sides of CA remained unchanged (LCA: 555.7 ± 326.9 vs. 578.6 ± 328.0 mL/min, P = 0.27; RCA: 550.0 ± 331.1 vs. 533.0 ± 303.5 mL/min, P = 0.30). The LCA BFR dramatically increased after turning the IABP off (296.8 ± 129.7 vs. 401.4 ± 278.1 mL/min, P = 0.02) in patients with cardiac stunning (defined as pulse pressure ≤ 5 mmHg). However, there was no significant difference in LCA BFR between IABP‐On and IABD‐Off (359.6 ± 105.4 mL/min vs. 389.6 ± 139.3 mL/min, P = 0.31) in patients with cardiac stunning receiving a higher ECMO blood flow (> 3.5 L/min).ConclusionsConcomitant IABP used in patients undergoing femoro‐femoral VA‐ECMO was associated with increased aortic VTI and BFR in bilateral FA. The change in CA BFR depended on cardiac function. A decreased LCA BFR was observed in patients with cardiac stunning when IABP was turned on, which might be compensated by a higher ECMO blood flow. Further study is needed to confirm the relationship between BFR and extremities and neurological complications.

BACKGROUND The Fontan operation is the only treatment option to change the anatomy of the heart and help improve patients’ hemodynamics. After successful operation, patients typically recover the ability to engage in general physical activity. As a better ventilatory strategy, extracorporeal membrane oxygenation (ECMO) provides gas exchange via an extracorporeal circuit, and is increasingly being used to improve respiratory and circulatory function. After the modified Fontan operation, circulation is different from that of patients who are not subjected to the procedure. This paper describe a successful case using ECMO in curing influenza A infection in a young man, who was diagnosed with Tausing-Bing syndrome and underwent Fontan operation 13 years ago. The special cardiac structure and circulatory characteristics are explored in this case. CASE SUMMARY We report a successful case using ECMO in curing influenza A infection in a 23-year-old man, who was diagnosed with Tausing-Bing syndrome and underwent Fontan operation 13 years ago. The man was admitted to the intensive care unit with severe acute respiratory distress syndrome as a result of influenza A infection. He was initially treated by veno-venous (VV) ECMO, which was switched to veno-venous-arterial ECMO (VVA ECMO) 5 d later. As circulation and respiratory function gradually improved, the VVA ECMO equipment was removed on May 1, 2018. The patient was successfully withdrawn from artificial ventilation on May 28, 2018 and then discharged from hospital on May 30, 2018. CONCLUSION After the modified Fontan operation, circulation is different compared with that of patients who are not subjected to the procedure. There are certainly many differences between them when they receive the treatment of ECMO. Due to the special cardiac structure and circulatory characteristics, an individualized liquid management strategy is necessary and it might be better for them to choose an active circulation support earlier.

目的 对接受静脉-动脉体外膜氧合(V-A ECMO)辅助的心脏术后心源性休克患者血管并发症的发生情况进行分析,评估血管并发症发生的危险因素以及对患者预后的影响.方法 本研究为单中心回顾性研究,纳入2017年1月至2020年12月接受股静脉-股动静V-A ECMO辅助的成人心脏术后心源性休克(PCS)患者,根据有无血管并发症将患者分为两组,比较临床预后,并采用多因素分析确定血管并发症的危险因素.结果 331例接受V-A ECMO治疗的PCS患者中,118例(35.6％)发生血管并发症,其中6例(1.8％)出现下肢缺血或插管处动脉血栓需手术干预,16例(4.8％)插管部位出血需要手术干预,其余96例(29.0％)出现轻度下肢缺血无须处理.年龄大于或等于60岁(OR 1.797,P=0.020)、ECMO前6 h血乳酸水平(OR 1.062,P=0.002)、ECMO前6 h序贯器官衰竭(SOFA)评分(OR 1.160,P=0.025)、单纯冠状动脉旁路移植术(CABG)(OR 0.576,P=0.032)与血管并发症相关.有和无血管并发症患者的住院生存率分别为22.9％和45.5％(P<0.001).结论 血管并发症与较高的住院死亡率相关.年龄大于或等于60岁、ECMO前6 h血乳酸水平及SOFA评分是发生血管并发症的独立危险因素,而单纯CABG术则为血管并发症发生的独立保护性因素.

Background: The Fontan operation is the only treatment option to change the anatomy of the heart and help improve patients’ hemodynamics. After successful operation, patients typically recover the ability to engage in general physical activity. The mortality of patients diagnosed with acute respiratory distress syndrome (ARDS) ranges from 17.3 to 41.4% among critically ill patients with H1N1 infection. As a better ventilatory strategy, extracorporeal membrane oxygenation (ECMO) provides gas exchange via an extracorporeal circuit, and is increasingly being used to improve respiratory and circulatory function. As is known to all, after the modified Fontan operation, circulation was different compared with patients who were not subjected to the procedure. But very few articles describe the special circulation about the case who was post-operative of the modified Fontan operation especially when it received the treatment of E-CMO. This study aims to describe a successful case using E-CMO in curing the influenza A infection in a young man, who was diagnosed with Tausing-Bing syndrome and underwent Fontan operation thirteen years ago. We want to explore the special cardiac structure and circulatory characteristics in this case. Methods: To report a successful case using extracorporeal membrane oxygenation in curing the influenza A infection in a young man, who was diagnosed with Tausing-Bing syndrome and underwent Fontan operation thirteen years ago. In this article, we describe a 23-year-old man, with a history of modified Fontan operation for the Tausing-Bing syndrome, admitted to ICU with severe acute respiratory distress syndrome as a result of influenza A infection. The man was initially treated by V-V ECMO, five days later was switched to V-V-A E-CMO. Results: As circulation and respiratory function gradually improved, the VV-A ECMO equipment was removed on May 1, 2018.The patient was successfully withdrawn from artificial ventilation on May 28, 2018, then discharged from hospital on May 30, 2018. Conclusion: After the modified Fontan operation, circulation was different compared with patients who were not subjected to the procedure. There were certainly many differences between the two sides when they received the treatment of E-CMO. As the special cardiac structure and circulatory characteristics, an individualized liquid management strategy was necessary and it might be better for them to choose an active cycle support earlier.

A 54-year-old man presented to our clinic with a 6-month history of dyspnea and angina. The patient was diagnosed with obstructive coronary artery disease and severe mitral regurgitation. Preoperative transthoracic echocardiography (TTE) showed regional wall motion abnormalities and a regurgitant area of 8 cm2. The left ventricular ejection fraction was 22%. Myocardial perfusion imaging by single-photon emission CT detected approximately 30% viable myocardium in the left ventricle (LV). The patient underwent successful coronary artery bypass grafting and mitral valve repair. Peripheral venoarterial extracorporeal membrane oxygenation (VA-ECMO) was initiated after unsuccessful attempts to wean the patient from cardiopulmonary bypass. Cannulation was performed with use of a right femoral venous drainage cannula (21F) and a right femoral arterial reinfusion cannula (15F). Because the VA-ECMO created LV distension, a venous cannula (16F) was inserted into the right superior pulmonary vein and connected to the femoral venous drainage cannula to reduce LV filling pressures. On the first day of VA-ECMO support, the images of routine TTE and subsequent transesophageal echocardiography (TEE) are shown in Videos 1 and 2. Question: On reviewing images of echocardiography, which is the most likely diagnosis in this clinical context? Based on the clinical information and the echocardiography, what would you recommend as the next step? Answer: TEE findings included absence of blood flow, severe blood stasis, and thrombus formation in the LV (Videos 1 and 2). The most likely diagnosis in the clinical context that we have described was severe spontaneous echo contrast (SEC) and severe blood stasis, rather than LV thrombus. The primary goals are to open up the aortic valve and reverse severe blood stasis in the LV VA-ECMO is a well-established form of short-term mechanical circulatory support for patients in severe cardiogenic shock. In such cases, VA-ECMO can fully replace the functions of the heart and lungs, maintaining systemic blood circulation and pulmonary gas exchange to ensure adequate organ perfusion and tissue oxygenation. During peripheral femoral VA-ECMO, blood is extracted from the right atrium via the femoral vein and returned to the arterial systemic circulation via the femoral artery. The retrograde infusion of arterialized blood into the thoracic aorta has been shown to significantly increase LV afterload and reduce the LV stroke volume simultaneously.1Burkhoff D. Sayer G. Doshi D. et al.Hemodynamics of mechanical circulatory support.J Am Coll Cardiol. 2015; 66: 2663-2674Crossref PubMed Scopus (226) Google Scholar Cardiogenic shock is characterized by a low ejection fraction, decreased stroke volume, low pressure generation, and high LV end-diastolic pressure. The main hemodynamic effect triggered by the increasing VA-ECMO flow is an increase in LV afterload.1Burkhoff D. Sayer G. Doshi D. et al.Hemodynamics of mechanical circulatory support.J Am Coll Cardiol. 2015; 66: 2663-2674Crossref PubMed Scopus (226) Google Scholar Ostadal et al2Ostadal P. Mlcek M. Kruger A. et al.Increasing venoarterial extracorporeal membrane oxygenation flow negatively affects left ventricular performance in a porcine model of cardiogenic shock.J Transl Med. 2015; 13: 266Crossref PubMed Scopus (56) Google Scholar showed that decreasing VA-ECMO flow resulted in improvements in several parameters of LV performance in animals in cardiogenic shock. When LV systolic function was severely compromised, increases in afterload and the bronchial arterial circulation further contributed to the LV overload. If the LV cannot compensate for the increasing afterload through the Frank-Starling mechanism, the aortic valve does not open, and the blood accumulates in the LV. In another study, coronary angiography showed that patients with severe cardiac dysfunction had extremely slow flow even in the nonoccluded coronary arteries after extracorporeal CPR.3Sugiyama K. Takahashi M. Miyazaki K. et al.Left ventricular wall findings in non-electrocardiography-gated contrast-enhanced computed tomography after extracorporeal cardiopulmonary resuscitation.Crit Care. 2019; 23: 357Crossref PubMed Scopus (1) Google Scholar Thus, severe blood stasis in the LV and severe cardiac dysfunction may predict poor recovery of LV function in patients who receive VA-ECMO. SEC is an echogenic, swirling pattern of blood flow that can develop in any cardiac chamber if the velocity of blood flow is extremely low. SEC might increase risk for thrombogenesis.4Unai S. Nguyen M.L. Tanaka D. et al.Clinical significance of spontaneous echo contrast on extracorporeal membrane oxygenation.Ann Thorac Surg. 2017; 103: 773-778Abstract Full Text Full Text PDF PubMed Scopus (17) Google Scholar In patients who are receiving peripheral femoral VA-ECMO, SEC is often associated with reduced aortic valve opening and low pulsatility. Additionally, SEC may suggest increased afterload and LV distension. Presence of SEC increases the risk for impaired recovery of LV function by inducing subendocardial ischemia, increased myocardial oxygen consumption, and subsequent pulmonary edema.5Douflé G. Roscoe A. Billia F. et al.Echocardiography for adult patients supported with extracorporeal membrane oxygenation.Crit Care. 2015; 19: 326Crossref PubMed Scopus (67) Google Scholar The goal is to facilitate aortic valve opening and, thus, resolve the blood stasis in the LV. In our center, when absence of opening of the aortic valve and LV blood stasis are detected in a patient, the ECMO flow is gradually decreased to improve the ejection fraction. If the ECMO flow point at which the aortic valve reopens is too low for adequate organ perfusion, we reduce the ECMO flow rate significantly to achieve aortic valve opening within a short period (approximately 0.5 minute) until the blood stasis resolves completely (Videos 3, 4). Subsequently, the flow rate is restored to the original setting. If the aortic valve fails to open, severe blood stasis can be observed again within minutes (Videos 5, 6). We typically decrease the pump flow rate gradually, every 1 to 2 hours, to ensure intermittent disruption of the thrombogenesis in the LV. To date, no LV or aortic root thrombi have been detected in any patients in our center during the implementation of this protocol.6Cui Y. Wang H. Hou X. Prevent thrombus formation: what we are doing.Crit Care Med. 2018; 46e821Crossref PubMed Scopus (2) Google Scholar LV decompression is necessary to prevent myocardial ischemia and facilitate ventricular recovery. In our hospital, the unloading of the LV is typically achieved by placing a venous cannula into the left atrium through the right upper pulmonary vein. A large-bore cannula can ensure effective and secure LV unloading in most cases. However, in the case described herein, the intact mitral valve prevented the stagnating blood in the LV from draining through the right upper pulmonary venous cannula. The right superior pulmonary venous cannula was surgically repositioned to the LV apex, and the femoral VA-ECMO cannulas were left in place to ensure the effective unloading of the LV filling pressure and to inhibit thrombus formation. No macroscopic thrombus was observed during the surgical repositioning of the cannula. TTE obtained after this surgical procedure confirmed that there was no blood stasis or sedimentation of blood particles in the LV (Video 7). Making a clear echocardiographic distinction between severe blood stasis and a firm thrombus in patients who are receiving VA-ECMO support is often a challenging task, even for experienced physicians. Severe blood stasis seems to be reversible after the aortic valve reopens. In a recent case series, TEE showed suspected thrombi that adhered to the aortic root, which were not observed by the surgeons.7Hireche-Chikaoui H. Grübler M.R. Bloch A. et al.Nonejecting hearts on femoral veno-arterial extracorporeal membrane oxygenation: aortic root blood stasis and thrombus formation—a case series and review of the literature.Crit Care Med. 2018; 46: e459-e464Crossref PubMed Scopus (20) Google Scholar In conclusion, absence of aortic valve opening and the appearance of SEC on echocardiography do not confirm the presence of clinically relevant thrombi in patients who are receiving VA-ECMO, especially during the early days after ECMO is initiated. However, clinicians must be aware that long-term blood stasis will increase the risk for thrombosis. Our case suggests that unloading the LV is an effective method of opening the aortic valve during peripheral femoral VA-ECMO. An intermittent decrease in the ECMO flow can easily achieve opening of the aortic valve. Serial echocardiography provides real-time visualization of the cardiac function. However, adequate interpretation of the echocardiographic images is a key step toward improving patient management and outcomes. 1.Echocardiography is an essential tool for monitoring patients who are receiving ECMO support.2.Echocardiography can reveal severe LV dysfunction associated with severe blood stasis and SEC during peripheral VA-ECMO. Adequate interpretation of the echocardiographic images is necessary to distinguish between SEC and other entities and to guide management in such cases.3.Unloading of the LV is a key step toward ventricular recovery. Serial echocardiography can be used to monitor the outcomes of different LV decompression methods. Financial/nonfinancial disclosures: None declared. Other contributions: CHEST worked with the authors to ensure that the Journal policies on patient consent to report information were met. Additional information: To analyze this case with the videos, see the online article. https://journal.chestnet.org/cms/asset/31118f8d-1e39-45fc-ae92-4487d756d3c0/mmc1.mp4Loading ... Download .mp4 (1.12 MB) Help with .mp4 files Video 1Apical four-chamber view (TTE): shows blood stasis and the beginning of thrombus formation in the LV.https://journal.chestnet.org/cms/asset/91070288-9228-44cb-af02-dca2cc62e3a0/mmc2.mp4Loading ... Download .mp4 (0.58 MB) Help with .mp4 files Video 2Midesophageal four-chamber view (TEE): shows blood stasis and the beginning of thrombus formation in the LV.https://journal.chestnet.org/cms/asset/5a377cdd-7580-436d-8749-95a750107987/mmc3.mp4Loading ... Download .mp4 (1.12 MB) Help with .mp4 files Video 3Apical four-chamber view (TTE): shows dissipation of the blood stasis and sedimentation.https://journal.chestnet.org/cms/asset/b2e4756f-44b4-48b0-bf73-c2245ea586e6/mmc4.mp4Loading ... Download .mp4 (0.6 MB) Help with .mp4 files Video 4Midesophageal four-chamber view (TEE): shows dissipation of the blood stasis and sedimentation.https://journal.chestnet.org/cms/asset/b19b3c5f-25b5-4ef4-adee-f7fe1a30e8c2/mmc5.mp4Loading ... Download .mp4 (1.12 MB) Help with .mp4 files Video 5Apical four-chamber view (TTE): shows reoccurrence of blood stasis and sedimentation in the LV.https://journal.chestnet.org/cms/asset/f5698143-22fb-46fd-a7d7-e623085bc56d/mmc6.mp4Loading ... Download .mp4 (0.58 MB) Help with .mp4 files Video 6Midesophageal four-chamber view (TEE): shows reoccurrence of blood stasis and sedimentation in the LV.https://journal.chestnet.org/cms/asset/29aa79ff-6a56-42ee-8443-ee33f9842bff/mmc7.mp4Loading ... Download .mp4 (1.09 MB) Help with .mp4 files Video 7Apical four-chamber view (TTE): shows a cannula through the apex of the LV and absence of blood stasis and sedimentation of blood particles in the LV.https://journal.chestnet.org/cms/asset/a125d81e-8faf-4b13-aa30-31bfcf765a0c/mmc8.mp4Loading ... Download .mp4 (17 MB) Help with .mp4 files Video 8

Objective:To investigate the safety and the efficacy of percutaneous and surgical approach in femoro-femoral veno-arterial extracorporeal membrane oxygenation (VA-ECMO) cannulation.Methods:All consecutive patients implanted with femoro-femoral VA-ECMO between January 2018 and December 2020 in Beijing Anzhen Hospital, Capital Medical University. Propensity score matching was used to compare outcomes of percutaneous and surgical groups while controlling for confounders.Results:Among the 276 patients who received femoro-femoral VA-ECMO (62 surgical and 214 percutaneous), propensity-score matching selected 52 pairs of patients with similar characteristics with mean age of(59.6±13.0)years old, in which 26 patients were female. There were a lower ECMO cannulation-associated complication (28.8% vs. 48.1%, P=0.044) and a lower hospital mortality (42.3% vs. 67.3%, P=0.010) in the percutaneous group. The circuit blood flow after ECMO initiation was similar in both groups[(3.3±0.8)L·min -1·kg -1 in percutaneous group vs. (3.2±0.7)L·min -1·kg -1 in surgical group, P=0.738]. The serum lactate was declined in both group after ECMO initiation[(5.4±5.8)mmol/L vs. (9.2±6.9)mmol/L, P<0.001 in percutaneous group; (6.3±6.2)mmol/L vs. (10.5±7.0)mmol/L, P=0.003 in surgical group]. Conclusion:Percutaneous approach is a safe and efficient technique in emoro-femoral VA-ECMO cannulation. Compared with surgical cannulation, percutaneous approach is associated with lower ECMO cannulation-associated complication and lower hospital mortality.

A 16-year-old boy presented to the ED with a 2-day history of dyspnea and hypotension. The patient experienced cardiogenic shock and was diagnosed with fulminant myocarditis. Maintaining hemodynamic stability was a challenge despite the IV administration of large doses of positive inotropic and vasoactive agents. Transthoracic echocardiography (TTE) revealed severe cardiac dysfunction. Femoral venoarterial extracorporeal membrane oxygenation (VA-ECMO) was initiated under ultrasound guidance. Cannulation was performed with use of a right femoral artery reinfusion cannula (15F) and a left femoral venous drainage cannula (21F). The patient's clinical status improved during VA-ECMO support with administration of anticoagulation therapy. VA-ECMO was discontinued after 7 days. TTE after decannulation detected a cannula-shaped structure in the inferior vena cava (IVC), where the femoral venous drainage cannula had been placed during VA-ECMO support. (Video 1, Fig 1A, C, D). Surprisingly, TTE detected blood flow signals in the cannula-shaped structure (Fig 1B).Question: Based on the echocardiographic images included, what is the most likely diagnosis in this clinical context? After reviewing the clinical information and the echocardiographic images, what would you recommend as the next step?Answer: The most likely diagnosis in the clinical context we have described is long- segment caval thrombus. After the administration of anticoagulation therapy, repeat TTE assessments showed no residual thrombotic material 10 days later (Video 2). The patient did not experience symptoms or clinical signs suggestive of IVC syndrome (eg, lower extremity edema) or pulmonary embolism (eg, dyspnea)DiscussionCannula-associated DVT has been linked to the activation of the coagulation system induced by the contact of blood with nonbiological artificial materials.1Annich G.M. Zaulan O. Neufeld M. et al.Thromboprophylaxis in extracorporeal circuits: current pharmacological strategies and future directions.Am J Cardiovasc Drugs. 2017; 17: 425-439Crossref PubMed Scopus (22) Google Scholar The diagnosis of DVT is established based on incompressibility of peripheral veins, absence of blood flow, and visualization of thrombi, typically by echocardiography and CT. In some reports, cannula-associated DVT after discontinuation of venovenous ECMO (VV-ECMO) affected between 18.1% and 71.4% of surviving patients.2Cooper E. Burns J. Retter A. et al.Prevalence of venous thrombosis following venovenous extracorporeal membrane oxygenation in patients with severe respiratory failure.Crit Care Med. 2015; 43: e581-e584Crossref PubMed Scopus (66) Google Scholar, 3Parzy G. Daviet F. Persico N. et al.Prevalence and risk factors for thrombotic complications following venovenous extracorporeal membrane oxygenation: a CT scan study.Crit Care Med. 2020; 48: 192-199Crossref PubMed Scopus (21) Google Scholar, 4Fisser C. Reichenbächer C. Müller T. et al.Incidence and risk factors for cannula- related venous thrombosis after venovenous extracorporeal membrane oxygenation in adult patients with acute respiratory failure.Crit Care Med. 2019; 47: e332-e339Crossref PubMed Scopus (36) Google Scholar Studies published in recent years have reported superior and inferior vena cava thrombosis rates as high as 51.7% at autopsy.5Trudzinski F.C. Minko P. Rapp D. et al.Runtime and aPTT predict venous thrombosis and thromboembolism in patients on extracorporeal membrane oxygenation: a retrospective analysis.Ann Intensive Care. 2016; 6: 66Crossref PubMed Scopus (37) Google Scholar These findings suggest that cannula- associated DVT is a common complication after withdrawal of VV-ECMO. However, massive cannula- associated DVT after discontinuation of VV-ECMO has been reportedinfrequently.6Bein T. Philipp A. Pregler B. et al.Long-segment caval thrombus after removal of ECMO cannula.Intensive Care Med. 2015; 41: 1967-1968Crossref PubMed Scopus (6) Google ScholarThe pathogenesis of cannula-associated DVT involves rheological changes caused by the blood flow around the cannulas, which may increase thrombogenic potential. The main challenge of anticoagulation therapy during ECMO is to maintain the delicate balance between a reduction in thrombotic risk and prevention of hemorrhage. The activated partial thromboplastin time (aPTT) test has been used to guide and monitor anticoagulation therapy with unfractionated heparin (UFH). However, aPTT is not a reliable measure of anticoagulant effects in practice. A higher level of aPTT has not been associated with a lower frequency of cannula-associated DVT.3Parzy G. Daviet F. Persico N. et al.Prevalence and risk factors for thrombotic complications following venovenous extracorporeal membrane oxygenation: a CT scan study.Crit Care Med. 2020; 48: 192-199Crossref PubMed Scopus (21) Google Scholar Multiple variables, including baseline aPTT levels, which may vary between critically ill patients and normal control subjects, influence the reliability of the aPTT test for monitoring UFH therapeutic ranges. Additionally, studies about the predictive value of other blood coagulation indicators, such as prothrombin time, fibrinogen level, mean platelet count, and D-dimer value, for thrombotic events have reached discordant conclusions.4Fisser C. Reichenbächer C. Müller T. et al.Incidence and risk factors for cannula- related venous thrombosis after venovenous extracorporeal membrane oxygenation in adult patients with acute respiratory failure.Crit Care Med. 2019; 47: e332-e339Crossref PubMed Scopus (36) Google Scholar,5Trudzinski F.C. Minko P. Rapp D. et al.Runtime and aPTT predict venous thrombosis and thromboembolism in patients on extracorporeal membrane oxygenation: a retrospective analysis.Ann Intensive Care. 2016; 6: 66Crossref PubMed Scopus (37) Google Scholar The coagulation indicators that are commonly used during ECMO support are likely insufficient for accurate anticoagulation monitoring. Although effective anticoagulation is necessary to prevent cannula-associated DVT, no universally accepted standard for anticoagulation monitoring is currently available in clinical practice. Further research is needed to improve anticoagulation protocols and achieve reliable anticoagulation monitoring, to successfully prevent cannula-associated DVT.The heterogeneous distribution of cannula-associated DVT is determined by the different cannulation approaches. A greater diameter of the cannula often correlateswith a higher risk of cannula-associated DVT.2Cooper E. Burns J. Retter A. et al.Prevalence of venous thrombosis following venovenous extracorporeal membrane oxygenation in patients with severe respiratory failure.Crit Care Med. 2015; 43: e581-e584Crossref PubMed Scopus (66) Google Scholar,4Fisser C. Reichenbächer C. Müller T. et al.Incidence and risk factors for cannula- related venous thrombosis after venovenous extracorporeal membrane oxygenation in adult patients with acute respiratory failure.Crit Care Med. 2019; 47: e332-e339Crossref PubMed Scopus (36) Google Scholar Therefore, cannula-associated DVT occurs more frequently in the IVC, because the drainage cannula placed in the IVC is usually the largest one. In our center, cannula-associated DVT after VA-ECMO decannulation was detected by TTE in only a few patients. The low number of cases may be explained by our protocol and the characteristics of the patient population in our center. First, we implanted smaller drainage cannulas (19-21 F) in patients. A small cannula may have little effect on the thrombogenic potential of the blood surrounding it. Second, most of the patients in our center received VA-ECMO support for cardiogenic shock. Whether the particular hemodynamic changes associated with the two types of ECMO will have different effects on blood thrombogenicity around the cannula is unclear. Researchers have focused mostly on cannula-associated DVT during VV-ECMO support. Few reports have been published about cannula- associated DVT after discontinuation of VA-ECMO.A retrospective observational analysis showed that in-hospital mortality rates and death rates at discharge from the ICU and at 90 days did not differ significantly between patients with cannula-associated DVT and those who did not experience this complication.3Parzy G. Daviet F. Persico N. et al.Prevalence and risk factors for thrombotic complications following venovenous extracorporeal membrane oxygenation: a CT scan study.Crit Care Med. 2020; 48: 192-199Crossref PubMed Scopus (21) Google Scholar However, despite the lack of statistical significance, the in-hospital mortality rate was higher in the cannula-associated DVT group, suggesting that thrombotic events related to VV-ECMO may have an impact on mortality outcomes.2Cooper E. Burns J. Retter A. et al.Prevalence of venous thrombosis following venovenous extracorporeal membrane oxygenation in patients with severe respiratory failure.Crit Care Med. 2015; 43: e581-e584Crossref PubMed Scopus (66) Google Scholar,3Parzy G. Daviet F. Persico N. et al.Prevalence and risk factors for thrombotic complications following venovenous extracorporeal membrane oxygenation: a CT scan study.Crit Care Med. 2020; 48: 192-199Crossref PubMed Scopus (21) Google Scholar Confirming the diagnosis of cannula-associated DVT is critical because DVT is associated with a potential risk of sudden death from pulmonary embolism.In theory, DVT can lead to IVC syndrome manifesting with edema of the lower limbs.However, this manifestation is not apparent in many patients with DVT, likely because, in most cases, the thrombus is too small to obstruct the blood flow in the IVC. Only a few patients, who have a long-segment DVT, develop IVC syndrome.6Bein T. Philipp A. Pregler B. et al.Long-segment caval thrombus after removal of ECMO cannula.Intensive Care Med. 2015; 41: 1967-1968Crossref PubMed Scopus (6) Google Scholar The patient in our case had a long-segment DVT but the blood continued to flow through the thrombus. IVC syndrome did not develop because the cannula-shaped thrombus was able to mitigate the passive venous congestion in the IVC.TTE has low sensitivity in detecting cannula-associated DVT when the cannulas are in situ during VA-ECMO support in this patient. Daily TTE was not able to confirm presence of the cannula-associated DVT while this patient was receiving VA-ECMO support. However, a long-segment thrombus was found immediately after removal of the cannula. The thrombus copied the shape of the cannula that had been removed. TTE can provide clear images of the cannula-associated DVT after removal of the cannula. The optimal treatment of long-segment IVC thrombosis after discontinuation of ECMO has yet to be determined. Options include anticoagulation as sole therapy, thrombolytic therapy, mechanical intervention, and surgical removal. In our case, implanting an IVC filter was challenging because the massive DVT had expanded above the level of the hepatic vein ostium. Surgical removal was not considered an appropriate first-line therapy because the patient was critically ill. Thrombolytic therapy carries a high risk of bleeding. Therefore, anticoagulation alone was considered the optimal choice for the treatment of the cannula-associated DVT in this patient. After the patient was treated solely with UFH, TTE assessment did not detect any residual thrombotic material after 10 days.Cannula-associated DVT is often underdiagnosed because most affected patients do not present with characteristic clinical features. Moreover, TTE does not show clear images of the thrombus during ECMO support. However, cannula-associated DVT can be detected by TTE immediately after removal of the cannula. UFH anticoagulation alone may be the optimal treatment choice in certain critically ill patients, such as the patient described in our case.Reverberations1.Cannula-associated DVT is a complication that occurs frequently after removal of VV-ECMO. However, a long-segment cannula-associated DVT is rare, especially in patients who receive VA-ECMO.2.TTE has low sensitivity for detecting cannula-associated DVT during ECMO support, but TEE can show clear images of DVT after removal of the cannula.3.UFH anticoagulation alone may be the optimal treatment for cannula- associated DVT confirmed by echocardiography. A 16-year-old boy presented to the ED with a 2-day history of dyspnea and hypotension. The patient experienced cardiogenic shock and was diagnosed with fulminant myocarditis. Maintaining hemodynamic stability was a challenge despite the IV administration of large doses of positive inotropic and vasoactive agents. Transthoracic echocardiography (TTE) revealed severe cardiac dysfunction. Femoral venoarterial extracorporeal membrane oxygenation (VA-ECMO) was initiated under ultrasound guidance. Cannulation was performed with use of a right femoral artery reinfusion cannula (15F) and a left femoral venous drainage cannula (21F). The patient's clinical status improved during VA-ECMO support with administration of anticoagulation therapy. VA-ECMO was discontinued after 7 days. TTE after decannulation detected a cannula-shaped structure in the inferior vena cava (IVC), where the femoral venous drainage cannula had been placed during VA-ECMO support. (Video 1, Fig 1A, C, D). Surprisingly, TTE detected blood flow signals in the cannula-shaped structure (Fig 1B). Question: Based on the echocardiographic images included, what is the most likely diagnosis in this clinical context? After reviewing the clinical information and the echocardiographic images, what would you recommend as the next step? Answer: The most likely diagnosis in the clinical context we have described is long- segment caval thrombus. After the administration of anticoagulation therapy, repeat TTE assessments showed no residual thrombotic material 10 days later (Video 2). The patient did not experience symptoms or clinical signs suggestive of IVC syndrome (eg, lower extremity edema) or pulmonary embolism (eg, dyspnea) DiscussionCannula-associated DVT has been linked to the activation of the coagulation system induced by the contact of blood with nonbiological artificial materials.1Annich G.M. Zaulan O. Neufeld M. et al.Thromboprophylaxis in extracorporeal circuits: current pharmacological strategies and future directions.Am J Cardiovasc Drugs. 2017; 17: 425-439Crossref PubMed Scopus (22) Google Scholar The diagnosis of DVT is established based on incompressibility of peripheral veins, absence of blood flow, and visualization of thrombi, typically by echocardiography and CT. In some reports, cannula-associated DVT after discontinuation of venovenous ECMO (VV-ECMO) affected between 18.1% and 71.4% of surviving patients.2Cooper E. Burns J. Retter A. et al.Prevalence of venous thrombosis following venovenous extracorporeal membrane oxygenation in patients with severe respiratory failure.Crit Care Med. 2015; 43: e581-e584Crossref PubMed Scopus (66) Google Scholar, 3Parzy G. Daviet F. Persico N. et al.Prevalence and risk factors for thrombotic complications following venovenous extracorporeal membrane oxygenation: a CT scan study.Crit Care Med. 2020; 48: 192-199Crossref PubMed Scopus (21) Google Scholar, 4Fisser C. Reichenbächer C. Müller T. et al.Incidence and risk factors for cannula- related venous thrombosis after venovenous extracorporeal membrane oxygenation in adult patients with acute respiratory failure.Crit Care Med. 2019; 47: e332-e339Crossref PubMed Scopus (36) Google Scholar Studies published in recent years have reported superior and inferior vena cava thrombosis rates as high as 51.7% at autopsy.5Trudzinski F.C. Minko P. Rapp D. et al.Runtime and aPTT predict venous thrombosis and thromboembolism in patients on extracorporeal membrane oxygenation: a retrospective analysis.Ann Intensive Care. 2016; 6: 66Crossref PubMed Scopus (37) Google Scholar These findings suggest that cannula- associated DVT is a common complication after withdrawal of VV-ECMO. However, massive cannula- associated DVT after discontinuation of VV-ECMO has been reportedinfrequently.6Bein T. Philipp A. Pregler B. et al.Long-segment caval thrombus after removal of ECMO cannula.Intensive Care Med. 2015; 41: 1967-1968Crossref PubMed Scopus (6) Google ScholarThe pathogenesis of cannula-associated DVT involves rheological changes caused by the blood flow around the cannulas, which may increase thrombogenic potential. The main challenge of anticoagulation therapy during ECMO is to maintain the delicate balance between a reduction in thrombotic risk and prevention of hemorrhage. The activated partial thromboplastin time (aPTT) test has been used to guide and monitor anticoagulation therapy with unfractionated heparin (UFH). However, aPTT is not a reliable measure of anticoagulant effects in practice. A higher level of aPTT has not been associated with a lower frequency of cannula-associated DVT.3Parzy G. Daviet F. Persico N. et al.Prevalence and risk factors for thrombotic complications following venovenous extracorporeal membrane oxygenation: a CT scan study.Crit Care Med. 2020; 48: 192-199Crossref PubMed Scopus (21) Google Scholar Multiple variables, including baseline aPTT levels, which may vary between critically ill patients and normal control subjects, influence the reliability of the aPTT test for monitoring UFH therapeutic ranges. Additionally, studies about the predictive value of other blood coagulation indicators, such as prothrombin time, fibrinogen level, mean platelet count, and D-dimer value, for thrombotic events have reached discordant conclusions.4Fisser C. Reichenbächer C. Müller T. et al.Incidence and risk factors for cannula- related venous thrombosis after venovenous extracorporeal membrane oxygenation in adult patients with acute respiratory failure.Crit Care Med. 2019; 47: e332-e339Crossref PubMed Scopus (36) Google Scholar,5Trudzinski F.C. Minko P. Rapp D. et al.Runtime and aPTT predict venous thrombosis and thromboembolism in patients on extracorporeal membrane oxygenation: a retrospective analysis.Ann Intensive Care. 2016; 6: 66Crossref PubMed Scopus (37) Google Scholar The coagulation indicators that are commonly used during ECMO support are likely insufficient for accurate anticoagulation monitoring. Although effective anticoagulation is necessary to prevent cannula-associated DVT, no universally accepted standard for anticoagulation monitoring is currently available in clinical practice. Further research is needed to improve anticoagulation protocols and achieve reliable anticoagulation monitoring, to successfully prevent cannula-associated DVT.The heterogeneous distribution of cannula-associated DVT is determined by the different cannulation approaches. A greater diameter of the cannula often correlateswith a higher risk of cannula-associated DVT.2Cooper E. Burns J. Retter A. et al.Prevalence of venous thrombosis following venovenous extracorporeal membrane oxygenation in patients with severe respiratory failure.Crit Care Med. 2015; 43: e581-e584Crossref PubMed Scopus (66) Google Scholar,4Fisser C. Reichenbächer C. Müller T. et al.Incidence and risk factors for cannula- related venous thrombosis after venovenous extracorporeal membrane oxygenation in adult patients with acute respiratory failure.Crit Care Med. 2019; 47: e332-e339Crossref PubMed Scopus (36) Google Scholar Therefore, cannula-associated DVT occurs more frequently in the IVC, because the drainage cannula placed in the IVC is usually the largest one. In our center, cannula-associated DVT after VA-ECMO decannulation was detected by TTE in only a few patients. The low number of cases may be explained by our protocol and the characteristics of the patient population in our center. First, we implanted smaller drainage cannulas (19-21 F) in patients. A small cannula may have little effect on the thrombogenic potential of the blood surrounding it. Second, most of the patients in our center received VA-ECMO support for cardiogenic shock. Whether the particular hemodynamic changes associated with the two types of ECMO will have different effects on blood thrombogenicity around the cannula is unclear. Researchers have focused mostly on cannula-associated DVT during VV-ECMO support. Few reports have been published about cannula- associated DVT after discontinuation of VA-ECMO.A retrospective observational analysis showed that in-hospital mortality rates and death rates at discharge from the ICU and at 90 days did not differ significantly between patients with cannula-associated DVT and those who did not experience this complication.3Parzy G. Daviet F. Persico N. et al.Prevalence and risk factors for thrombotic complications following venovenous extracorporeal membrane oxygenation: a CT scan study.Crit Care Med. 2020; 48: 192-199Crossref PubMed Scopus (21) Google Scholar However, despite the lack of statistical significance, the in-hospital mortality rate was higher in the cannula-associated DVT group, suggesting that thrombotic events related to VV-ECMO may have an impact on mortality outcomes.2Cooper E. Burns J. Retter A. et al.Prevalence of venous thrombosis following venovenous extracorporeal membrane oxygenation in patients with severe respiratory failure.Crit Care Med. 2015; 43: e581-e584Crossref PubMed Scopus (66) Google Scholar,3Parzy G. Daviet F. Persico N. et al.Prevalence and risk factors for thrombotic complications following venovenous extracorporeal membrane oxygenation: a CT scan study.Crit Care Med. 2020; 48: 192-199Crossref PubMed Scopus (21) Google Scholar Confirming the diagnosis of cannula-associated DVT is critical because DVT is associated with a potential risk of sudden death from pulmonary embolism.In theory, DVT can lead to IVC syndrome manifesting with edema of the lower limbs.However, this manifestation is not apparent in many patients with DVT, likely because, in most cases, the thrombus is too small to obstruct the blood flow in the IVC. Only a few patients, who have a long-segment DVT, develop IVC syndrome.6Bein T. Philipp A. Pregler B. et al.Long-segment caval thrombus after removal of ECMO cannula.Intensive Care Med. 2015; 41: 1967-1968Crossref PubMed Scopus (6) Google Scholar The patient in our case had a long-segment DVT but the blood continued to flow through the thrombus. IVC syndrome did not develop because the cannula-shaped thrombus was able to mitigate the passive venous congestion in the IVC.TTE has low sensitivity in detecting cannula-associated DVT when the cannulas are in situ during VA-ECMO support in this patient. Daily TTE was not able to confirm presence of the cannula-associated DVT while this patient was receiving VA-ECMO support. However, a long-segment thrombus was found immediately after removal of the cannula. The thrombus copied the shape of the cannula that had been removed. TTE can provide clear images of the cannula-associated DVT after removal of the cannula. The optimal treatment of long-segment IVC thrombosis after discontinuation of ECMO has yet to be determined. Options include anticoagulation as sole therapy, thrombolytic therapy, mechanical intervention, and surgical removal. In our case, implanting an IVC filter was challenging because the massive DVT had expanded above the level of the hepatic vein ostium. Surgical removal was not considered an appropriate first-line therapy because the patient was critically ill. Thrombolytic therapy carries a high risk of bleeding. Therefore, anticoagulation alone was considered the optimal choice for the treatment of the cannula-associated DVT in this patient. After the patient was treated solely with UFH, TTE assessment did not detect any residual thrombotic material after 10 days.Cannula-associated DVT is often underdiagnosed because most affected patients do not present with characteristic clinical features. Moreover, TTE does not show clear images of the thrombus during ECMO support. However, cannula-associated DVT can be detected by TTE immediately after removal of the cannula. UFH anticoagulation alone may be the optimal treatment choice in certain critically ill patients, such as the patient described in our case. Cannula-associated DVT has been linked to the activation of the coagulation system induced by the contact of blood with nonbiological artificial materials.1Annich G.M. Zaulan O. Neufeld M. et al.Thromboprophylaxis in extracorporeal circuits: current pharmacological strategies and future directions.Am J Cardiovasc Drugs. 2017; 17: 425-439Crossref PubMed Scopus (22) Google Scholar The diagnosis of DVT is established based on incompressibility of peripheral veins, absence of blood flow, and visualization of thrombi, typically by echocardiography and CT. In some reports, cannula-associated DVT after discontinuation of venovenous ECMO (VV-ECMO) affected between 18.1% and 71.4% of surviving patients.2Cooper E. Burns J. Retter A. et al.Prevalence of venous thrombosis following venovenous extracorporeal membrane oxygenation in patients with severe respiratory failure.Crit Care Med. 2015; 43: e581-e584Crossref PubMed Scopus (66) Google Scholar, 3Parzy G. Daviet F. Persico N. et al.Prevalence and risk factors for thrombotic complications following venovenous extracorporeal membrane oxygenation: a CT scan study.Crit Care Med. 2020; 48: 192-199Crossref PubMed Scopus (21) Google Scholar, 4Fisser C. Reichenbächer C. Müller T. et al.Incidence and risk factors for cannula- related venous thrombosis after venovenous extracorporeal membrane oxygenation in adult patients with acute respiratory failure.Crit Care Med. 2019; 47: e332-e339Crossref PubMed Scopus (36) Google Scholar Studies published in recent years have reported superior and inferior vena cava thrombosis rates as high as 51.7% at autopsy.5Trudzinski F.C. Minko P. Rapp D. et al.Runtime and aPTT predict venous thrombosis and thromboembolism in patients on extracorporeal membrane oxygenation: a retrospective analysis.Ann Intensive Care. 2016; 6: 66Crossref PubMed Scopus (37) Google Scholar These findings suggest that cannula- associated DVT is a common complication after withdrawal of VV-ECMO. However, massive cannula- associated DVT after discontinuation of VV-ECMO has been reported infrequently.6Bein T. Philipp A. Pregler B. et al.Long-segment caval thrombus after removal of ECMO cannula.Intensive Care Med. 2015; 41: 1967-1968Crossref PubMed Scopus (6) Google Scholar The pathogenesis of cannula-associated DVT involves rheological changes caused by the blood flow around the cannulas, which may increase thrombogenic potential. The main challenge of anticoagulation therapy during ECMO is to maintain the delicate balance between a reduction in thrombotic risk and prevention of hemorrhage. The activated partial thromboplastin time (aPTT) test has been used to guide and monitor anticoagulation therapy with unfractionated heparin (UFH). However, aPTT is not a reliable measure of anticoagulant effects in practice. A higher level of aPTT has not been associated with a lower frequency of cannula-associated DVT.3Parzy G. Daviet F. Persico N. et al.Prevalence and risk factors for thrombotic complications following venovenous extracorporeal membrane oxygenation: a CT scan study.Crit Care Med. 2020; 48: 192-199Crossref PubMed Scopus (21) Google Scholar Multiple variables, including baseline aPTT levels, which may vary between critically ill patients and normal control subjects, influence the reliability of the aPTT test for monitoring UFH therapeutic ranges. Additionally, studies about the predictive value of other blood coagulation indicators, such as prothrombin time, fibrinogen level, mean platelet count, and D-dimer value, for thrombotic events have reached discordant conclusions.4Fisser C. Reichenbächer C. Müller T. et al.Incidence and risk factors for cannula- related venous thrombosis after venovenous extracorporeal membrane oxygenation in adult patients with acute respiratory failure.Crit Care Med. 2019; 47: e332-e339Crossref PubMed Scopus (36) Google Scholar,5Trudzinski F.C. Minko P. Rapp D. et al.Runtime and aPTT predict venous thrombosis and thromboembolism in patients on extracorporeal membrane oxygenation: a retrospective analysis.Ann Intensive Care. 2016; 6: 66Crossref PubMed Scopus (37) Google Scholar The coagulation indicators that are commonly used during ECMO support are likely insufficient for accurate anticoagulation monitoring. Although effective anticoagulation is necessary to prevent cannula-associated DVT, no universally accepted standard for anticoagulation monitoring is currently available in clinical practice. Further research is needed to improve anticoagulation protocols and achieve reliable anticoagulation monitoring, to successfully prevent cannula-associated DVT. The heterogeneous distribution of cannula-associated DVT is determined by the different cannulation approaches. A greater diameter of the cannula often correlates with a higher risk of cannula-associated DVT.2Cooper E. Burns J. Retter A. et al.Prevalence of venous thrombosis following venovenous extracorporeal membrane oxygenation in patients with severe respiratory failure.Crit Care Med. 2015; 43: e581-e584Crossref PubMed Scopus (66) Google Scholar,4Fisser C. Reichenbächer C. Müller T. et al.Incidence and risk factors for cannula- related venous thrombosis after venovenous extracorporeal membrane oxygenation in adult patients with acute respiratory failure.Crit Care Med. 2019; 47: e332-e339Crossref PubMed Scopus (36) Google Scholar Therefore, cannula-associated DVT occurs more frequently in the IVC, because the drainage cannula placed in the IVC is usually the largest one. In our center, cannula-associated DVT after VA-ECMO decannulation was detected by TTE in only a few patients. The low number of cases may be explained by our protocol and the characteristics of the patient population in our center. First, we implanted smaller drainage cannulas (19-21 F) in patients. A small cannula may have little effect on the thrombogenic potential of the blood surrounding it. Second, most of the patients in our center received VA-ECMO support for cardiogenic shock. Whether the particular hemodynamic changes associated with the two types of ECMO will have different effects on blood thrombogenicity around the cannula is unclear. Researchers have focused mostly on cannula-associated DVT during VV-ECMO support. Few reports have been published about cannula- associated DVT after discontinuation of VA-ECMO. A retrospective observational analysis showed that in-hospital mortality rates and death rates at discharge from the ICU and at 90 days did not differ significantly between patients with cannula-associated DVT and those who did not experience this complication.3Parzy G. Daviet F. Persico N. et al.Prevalence and risk factors for thrombotic complications following venovenous extracorporeal membrane oxygenation: a CT scan study.Crit Care Med. 2020; 48: 192-199Crossref PubMed Scopus (21) Google Scholar However, despite the lack of statistical significance, the in-hospital mortality rate was higher in the cannula-associated DVT group, suggesting that thrombotic events related to VV-ECMO may have an impact on mortality outcomes.2Cooper E. Burns J. Retter A. et al.Prevalence of venous thrombosis following venovenous extracorporeal membrane oxygenation in patients with severe respiratory failure.Crit Care Med. 2015; 43: e581-e584Crossref PubMed Scopus (66) Google Scholar,3Parzy G. Daviet F. Persico N. et al.Prevalence and risk factors for thrombotic complications following venovenous extracorporeal membrane oxygenation: a CT scan study.Crit Care Med. 2020; 48: 192-199Crossref PubMed Scopus (21) Google Scholar Confirming the diagnosis of cannula-associated DVT is critical because DVT is associated with a potential risk of sudden death from pulmonary embolism. In theory, DVT can lead to IVC syndrome manifesting with edema of the lower limbs. However, this manifestation is not apparent in many patients with DVT, likely because, in most cases, the thrombus is too small to obstruct the blood flow in the IVC. Only a few patients, who have a long-segment DVT, develop IVC syndrome.6Bein T. Philipp A. Pregler B. et al.Long-segment caval thrombus after removal of ECMO cannula.Intensive Care Med. 2015; 41: 1967-1968Crossref PubMed Scopus (6) Google Scholar The patient in our case had a long-segment DVT but the blood continued to flow through the thrombus. IVC syndrome did not develop because the cannula-shaped thrombus was able to mitigate the passive venous congestion in the IVC. TTE has low sensitivity in detecting cannula-associated DVT when the cannulas are in situ during VA-ECMO support in this patient. Daily TTE was not able to confirm presence of the cannula-associated DVT while this patient was receiving VA-ECMO support. However, a long-segment thrombus was found immediately after removal of the cannula. The thrombus copied the shape of the cannula that had been removed. TTE can provide clear images of the cannula-associated DVT after removal of the cannula. The optimal treatment of long-segment IVC thrombosis after discontinuation of ECMO has yet to be determined. Options include anticoagulation as sole therapy, thrombolytic therapy, mechanical intervention, and surgical removal. In our case, implanting an IVC filter was challenging because the massive DVT had expanded above the level of the hepatic vein ostium. Surgical removal was not considered an appropriate first-line therapy because the patient was critically ill. Thrombolytic therapy carries a high risk of bleeding. Therefore, anticoagulation alone was considered the optimal choice for the treatment of the cannula-associated DVT in this patient. After the patient was treated solely with UFH, TTE assessment did not detect any residual thrombotic material after 10 days. Cannula-associated DVT is often underdiagnosed because most affected patients do not present with characteristic clinical features. Moreover, TTE does not show clear images of the thrombus during ECMO support. However, cannula-associated DVT can be detected by TTE immediately after removal of the cannula. UFH anticoagulation alone may be the optimal treatment choice in certain critically ill patients, such as the patient described in our case. Reverberations1.Cannula-associated DVT is a complication that occurs frequently after removal of VV-ECMO. However, a long-segment cannula-associated DVT is rare, especially in patients who receive VA-ECMO.2.TTE has low sensitivity for detecting cannula-associated DVT during ECMO support, but TEE can show clear images of DVT after removal of the cannula.3.UFH anticoagulation alone may be the optimal treatment for cannula- associated DVT confirmed by echocardiography. 1.Cannula-associated DVT is a complication that occurs frequently after removal of VV-ECMO. However, a long-segment cannula-associated DVT is rare, especially in patients who receive VA-ECMO.2.TTE has low sensitivity for detecting cannula-associated DVT during ECMO support, but TEE can show clear images of DVT after removal of the cannula.3.UFH anticoagulation alone may be the optimal treatment for cannula- associated DVT confirmed by echocardiography. Financial/nonfinancial disclosures: None declared. Other contributions: CHEST worked with the authors to ensure that the Journal policies on patient consent to report information were met. Additional information: To analyze this case with the videos, see the online article. Supplementary Datahttps://journal.chestnet.org/cms/asset/eec0abe8-16e5-4ee5-8165-497abb6334dc/mmc1.mp4Loading ... Download .mp4 (0.69 MB) Help with .mp4 files Video 1TTE of the IVC: subcostal view shows a cannula-shaped structure in the IVChttps://journal.chestnet.org/cms/asset/9464818c-1e98-4cf8-8050-d5cc2eed68e6/mmc2.mp4Loading ... Download .mp4 (0.76 MB) Help with .mp4 files Video 2TTE of the IVC: subcostal view shows no residual thrombotic material after 10 dayshttps://journal.chestnet.org/cms/asset/234390f7-0896-4fa3-a532-6a35f2d6e78e/mmc3.mp4Loading ... Download .mp4 (45.32 MB) Help with .mp4 files Video 3 https://journal.chestnet.org/cms/asset/eec0abe8-16e5-4ee5-8165-497abb6334dc/mmc1.mp4Loading ... Download .mp4 (0.69 MB) Help with .mp4 files Video 1TTE of the IVC: subcostal view shows a cannula-shaped structure in the IVChttps://journal.chestnet.org/cms/asset/9464818c-1e98-4cf8-8050-d5cc2eed68e6/mmc2.mp4Loading ... Download .mp4 (0.76 MB) Help with .mp4 files Video 2TTE of the IVC: subcostal view shows no residual thrombotic material after 10 dayshttps://journal.chestnet.org/cms/asset/234390f7-0896-4fa3-a532-6a35f2d6e78e/mmc3.mp4Loading ... Download .mp4 (45.32 MB) Help with .mp4 files Video 3

目的 评估建立专职体外生命支持(ECLS)团队对成人循环衰竭患者接受ECLS辅助治疗临床预后影响.方法 选取北京安贞医院成人心脏危重症中心循环衰竭接受ECLS辅助患者为研究对象,以2013年1月组建专职ECLS团队为界,将患者分为对照组(CG组,2012年12月前,n=180)和观察组(OG组,2013年1月后,n=490).比较两组患者的ECLS辅助情况与临床预后.结果 238例(35.5％)患者存活出院,OG组出院存活率较高(38.4％vs.27.8％,P<0.05)、年龄较大[(56.1±12.5)岁vs.(53.9±13.6)岁]、合并冠心病比率较高(62.％vs.42.8％)、循环衰竭到开始ECLS辅助时间间隔较短[(2.1±0.6)h vs.(4.2±2.9)h]、辅助开始时乳酸水平较低[(12.9±4.4)mmol/L vs.(9.5±3.3)mmol/L]、ECLS辅助期间严重下肢缺血并发症发生率较低(8.9％vs.4.3％)、ECLS辅助时间较长[(108.7±85.0)h vs.(95.3±70.2)h]、辅助期间平均消耗红细胞、新鲜冰冻血浆和血小板量较低,与CG组比较均有统计学意义(P<0.05).多元回归分析结果显示影响患者住院死亡高危风险因素有严重神经系统并发症、下肢严重缺血和肾脏功能衰竭需持续血液透析治疗,而建立专职ECLS团队是保护性因素.结论 ECLS能够为成人循环衰竭患者提供有效辅助,组建专职ECLS团队能够改善临床预后.

目的 分析体外膜氧合(ECMO)用于老年患者(年龄≥65岁)难治性心脏术后心源性休克(PCCS)的临床结果.方法 总结分析2004年5月至2017年12月间139例老年PCCS患者进行ECMO辅助临床资料,按照是否存活出院分为存活出院组(SG,n=34)和院内死亡组(DG,n=105),分析影响老年患者临床预后的相关风险因素.结果 71例(51.1％)患者成功撤机,34例(24.5％)患者存活出院.与SG组患者相比较,DG组患者启动ECMO时乳酸水平、血管活性药物指数和器官衰竭序贯评分较高,差异有统计学意义(P<0.01).DG组患者ECMO辅助期间严重神经系统并发症和肾脏功能衰竭需要持续性肾替代治疗(CRRT)发生率较高,差异有统计学意义(P<0.01).多元回归分析结果提示心脏功能衰竭、严重神经系统并发症和需要CRRT的肾脏功能衰竭是影响患者临床预后的独立高危风险因素.结论 ECMO能够为老年PCCS患者提供有效循环辅助,挽救部分患者生命.

Objectives: The benefit of preoperative intra-aortic balloon pump implantation in high-risk cardiac surgery patients is still debated. The role of preoperative intra-aortic balloon pump insertion in acute myocardial infarction patients without cardiogenic shock undergoing off-pump coronary artery bypass grafting remains unknown. This study aimed to determine the efficacy and safety of the preoperative intra-aortic balloon pump insertion in those patients undergoing off-pump coronary artery bypass grafting. Methods: A total of 421 consecutive acute myocardial infarction patients without cardiogenic shock who underwent isolated off-pump coronary artery bypass grafting were enrolled in this retrospective observational propensity score–matched analysis study. Patients who received intra-aortic balloon pump before off-pump coronary artery bypass grafting (the intra-aortic balloon pump group, n = 157) were compared with those who had not (control group, n = 264). The 30-day postoperative survival, postoperative complications, and postoperative hospital length of stay were compared between the two groups. Results: A total of 99 pairs of patients were matched. The preoperative intra-aortic balloon pump did not show a 30-day postoperative survival benefit compared with the control group (hazard ratio, 0.9; 95% confidence interval, 0.2-4.2; p = 0.92). Patients with preoperative intra-aortic balloon pump were more likely to have shorter postoperative lengths of stay (8 (6-11) days vs. 10 (6-15) days, p = 0.02) and decreased total days in the hospital (median days: 18.2 vs. 21.8, p = 0.02) compared to patients without balloon pumps. Conclusion: Preoperative intra-aortic balloon pump insertion in acute myocardial infarction patients without cardiogenic shock undergoing off-pump coronary artery bypass grafting improved convalescence as shown by significantly shorter postoperative lengths of hospital stay.

Objective:To investigate the relationship between serum lactate before initiation of venoarterial extracorporeal membrane oxygenation (VA-ECMO) and in-hospital mortality in adult patients with postcardiotomy refractory cardiogenic shock (PCCS).Methods:We analyzed 144 consecutive adult patients with PCCS received VA-ECMO support between January 2004 and December 2017. Patients were divided into two groups according to the serum lactate level before initiation of xVA-ECMO: low lactate group (LG, 54 cases) and high lactate group (HG, 90 cases). VA-ECMO support parameters and clinical outcomes were compared between the two groups.Results:92 (63.9%) patients were successfully weaned off VA-ECMO, and 52 (36.1%) were discharged. The inotrope scores, sequential organ failure assessment (SOFA) score at VA-ECMO initiation, and renal failure requiring renal replacement therapy during VA-ECMO support in patients with high lactate level were statistically higher ( P<0.05). The successfully wean off VA-ECMO (53.3% vs. 81.5%) and survival to discharge (16.7% vs. 68.5%) was significantly lower among patients in the HG group ( P<0.05). In multivariate analysis, high lactate levels before initiation of VA-ECMO remained the independent predictor of survival (odds ratio 11.9, 95% confidence interval 2.9-48.0, P<0.05). Conclusion:High lactate level(>8.6 mmol/L) before initiation of VA-ECMO is independently related to in-hospital mortality in adult patients with delayed refractory PCCS. This found may help clinicians to use VA-ECMO more effectively for those patients.

Objective To analyze the prognostic factors of extracorporeal membrane oxygenation(ECMO) in patients with delayed post-cardiotomy cardiogenic shock(PCCS).Methods A total of 144 adult patients with PCCS receiving ECMO in Beijing Anzhen Hospital,Capital Medical University from January 2006 to December 2016 were retrospectirely analyzed.According to the in-hospital outcomes,they were divided into survival group (n =52) and death group (n =92).Basic data,comorbidities,major surgical procedures,records of ECMO,complications,consumption of blood products and postoperative recovery were analyzed.Results Among the 144 patients,92 patients (63.9％) weaned from ECMO and 52 patients (36.1％) survived.Compared with survival group,the elderly(≥65 years old),valve replacement and valvuloplasty took higher ratios in death group [30.4％ (28/92) vs 15.4％ (8/52),38.0％ (35/92) vs 19.2％ (10/52)];patients with coronary heart disease and coronary artery bypass grafting took lower ratios in death group [42.4％ (39/92) vs 59.6％ (31/52),32.6％ (30/92) vs 50.0％ (26/52)] (all P ＜ 0.05).Incidences of limb ischemia,renal function failure required continuous renal replacement therapy(CRRT),severe neurological complication and sepsis in death group were higher than those in survival group[14.1％ (13/92) vs 0,79.3％ (73/92) vs 15.4％ (8/52),28.3％ (26/92) vs 3.8％ (2/52),31.5％ (29/92) vs 15.4％ (8/52)] (all P ＜ 0.05).Length of hospital stay in death group was shorter than that in survival group [21 (16,28) d vs 31 (21,43) d,P ＜ 0.001].Multivariate logistic regression analysis suggested that renal function failure required CRRT and severe neurological complication were risk factors of death in patients with PCCS undergoing ECMO(odds ratio =0.05,0.04;95％ confidence interval:0.01-0.22,0.01-0.28,both P ＜ 0.05).Conclusions ECMO can provide effective circulation support for patients with PCCS.Renal failure and severe neurological complication are death factors in PCCS patients undergoing ECMO.Active prevention of complications during ECMO is an important measure to improve the clinical unit.

Objective To identified the impact of extracorporeal cardiopulmonary resuscitation (ECPR) on survival and neurologic outcome in adults with refractory in-hospital cardiac arrest (IHCA).Methods All 74 adult patients who underwent ECPR for IHCA were enroued from July 2012 to December 2017 in Beiing Anzhen Hospital,Capital Medical University.Survival to discharge and cerebral performance category (CPC) scale were evaluated.The independent high-risk factors were determined using multivariate regression analysis models.Results Patients were discharged alive with favorable neurologic outcomes (CPC 1-2).Compared with patients in the SG group,the value of blood gas pH and extracellular residual alkaloids in the DG group were statistically lower (with P values below 0.05).The incidence of renal function failure requiring continuous renal replacement treatment (CRRT) and severe neurological complications were statistically higher in DG group patients.Multivariate regression analysis suggested that advanced age (age ≥ 65 years),renal function failure requiring CRRT,and severe neurological complications were independent high-risk factors for hospital death.Conclusions ECMO can provide stable hemodynamic support to inhospital cardiac arrest patients and save the lives of some patients.ECMO should be actively implanted when the cause of cardiac arrest is expected to be recoverable.

Objective To analyze the impact of age on outcomes in adult patients who underwent venoartieral extracorporeal membrane oxygenation (VA-ECMO) support for postcardiotomy cardiogenic shock (PCCS).Methods Totally 496 adult patients with PCCS who were implanted with VA-ECMO from September 2006 to December 2016 in Beijing Anzhen Hospital,Capital Medical University were retrospectively analyzed.The patients were divided into non-elderly group (18-＜ 65 years old,n =354) and elderly group (≥ 65 years old,n =142).Clinical characteristics,comorbidities,major cardiac procedures,pre-ECMO conditions,weaning and survival from VA-ECMO,ECMO-related complications and postoperative outcomes were assessed.Results The elderly group had significantly higher prevalences of comorbidities including hypertension,hyperlipidemia,coronary heart disease,intra-aortic balloon pump support,surgical history of pulmonary embolism and lower body length (P ＜ 0.05).Weaning from VA-ECMO was achieved in 62.4％ (221/354) of the non-elderly group and 49.3％ (70/142) of the elderly group;survival to discharge was 42.4％ (150/354) among the non-elderly group and 21.8％ (31/142) among the elderly group;the elderly group had a higher incidence of renal function dysfunction requiring continuous renal replacement therapy (CRRT) [44.1％ (156/354) vs 61.3 ％ (87/142)] (x2 =12.013,20.786,11.376;P =0.007,＜ 0.001,0.001).Adverse events including infection,re-exploration for bleeding,severe neurologic complication and severe limb ischemia were comparable in both groups (P ＞ 0.05).Multivariable logistic regression identified that advanced age,renal function dysfunction requiring CRRT,severe neurologic complication and severe limb ischemia were risk factors of in-hospital mortality in adult PCCS patients supported by VA-ECMO (odds ratio =3.38,9.65,11.08,6.14;95％ confidence interval:1.49-8.10,2.75-21.20,3.69-25.79,2.48-16.51;P=0.015,＜0.001,＜0.001,＜0.001).Conclusion VA-ECMO support can be used in adult patients with PCCS with acceptable adverse events.Some elderly patients can benefit from VA-ECMO but advanced age is a risk factor of in-hospital mortality.

目的:对桡动脉-大隐静脉组合V形桥新术式的安全性和近期移植血管通畅率进行初步探讨.方法:选自2015年4月至2016年3月,我院共完成29例桡动脉-大隐静脉组合V形桥冠状动脉旁路移植(CABG)术.平均年龄(65.3±8.2)岁,女性4例(16％).将大隐静脉与升主动脉做近端吻合,桡动脉与该大隐静脉端侧吻合,吻合口距升主动脉的距离≤0.5 cm.对术后30 d死亡率,桡动脉-大隐静脉组合V形桥吻合口以及远端吻合口的近期通畅性(术后6个月)进行影像学评价.结果:术后30 d死亡率为零;术后6个月对桡动脉-大隐静脉组合V形桥吻合口及远端吻合口的通畅性应用冠状动脉CTA进行评价,通畅率均为100％.结论:桡动脉-大隐静脉组合V形桥CABG术是一种安全有效的新术式,临床效果满意,近期通畅率高.

以微博、微信等为主导的微媒体已经成为大学校园的主要交流方式.在医学生的思想教育中,微媒体对于其教育内容、教育主体和教育环境等均产生了深远影响,带来了新的挑战.医德教育者需要积极应对这一时代性课题,把微媒体的技术优势和思想政治教育的传统优势结合起来,增强医学生思想教育的时代感、吸引力和实效性.

Background: This study aims to describe the prevalence of neurologic complications and hospital outcome in adult post-cardiotomy cardiogenic shock (PCS) patients receiving veno-arterial extracorporeal membrane oxygenation (V-A ECMO) support and factors associated with such adverse events.Methods: Four hundred and fifteen adult patients underwent cardiac surgery and received V-A ECMO for more than 24 h because of PCS. Patients were divided into two groups: those who developed a neurological complication and those who did not (control group). Multivariable logistic regression was performed to identify factors independently associated with neurologic complications.Results: Neurologic complications occurred in 87 patients (21.0%), including cerebral infarction in 33 patients (8.0%), brain death in 30 patients (7.2%), seizures in 14 patients (3.4%), and intracranial hemorrhage in 11 (2.7%) patients. In-hospital mortality in patients with neurologic complications was 90.8%, compared to 52.1% in control patients (p < 0.001). In a multivariable model, the lowest systolic blood pressure (SBP) level pre-ECMO (OR, 0.89; 95% CI: 0.86–0.93) and aortic surgery combined with coronary artery bypass grafting (OR, 9.22; 95% CI: 2.10–40.55) were associated with overall neurologic complications. Age (OR, 1.06; 95% CI: 1.01–1.12) and lowest SBP (OR, 0.81; 95% CI: 0.76–0.87) were correlative factors of brain death. Coagulation disorders (OR, 9.75; 95% CI: 1.83–51.89) and atrial fibrillation (OR, 12.19; 95% CI: 1.22–121.61) were shown to be associated independently with intracranial hemorrhage, whereas atrial fibrillation (OR, 8.15; 95% CI: 1.31–50.62) was also associated with cerebral infarction.Conclusions: Neurologic complications in adult PCS patients undergoing V-A ECMO support are frequent and associated with higher in-hospital mortality. Identified risk factors of neurologic complications might help to improve ECMO management and might reduce their occurrence.

Objective To evaluate the efficacy and safety of preoperative intra-aortic balloon pump(IABP) insertion in acute myocardial infarction(AMI) without cardiogenic shock(CS) patients receiving off-pump coronary artery bypass grafting ( OPCABG).Methods 444 consecutive AMI patients who underwent isolated OPCABG from January 2009 to December 2016 were enrolled.158 patients who underwent preoperative IABP placement(IABP group) and the other of 286 patients who did not have IABP placement(control group).The in-hospital mortality rate, postoperative complications, mechanical ventilation time, ICU stay and hospital length were compared between the two groups.Results The overall mortality was 5.0%.135 pairs of patients were matched.The preoperative IABP insertion showed benefits in postoperative survival rate compared with the control group(0 vs.5.9%, P＝0.004).However, patients with preoperative IABP were more likely to prolong duration of mechanical ventilation and ICU stay.The postoperative length of stay in hospital didn't show significant difference between the two groups.Conclusion Survival advantage was observed from preoperative IABP insertion in AMI patients without CS under-going OPCABG.

Center for Cardiac Intensive Care, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Beijing Anzhen Hospital, Capital Medical University, Beijing, China The authors have disclosed that they do not have any potential conflicts of interest.