Noonan syndrome is a relatively common genetic disorder and the second most common cause of congenital heart disease after trisomy 21. The spectrum of cardiac anomalies in Noonan syndrome typically involves pulmonary valve stenosis occasionally in conjunction with hypertrophic cardiomyopathy. Mitral valve involvement is a rare finding in Noonan syndrome and is most commonly associated with either mitral valve prolapse or abnormal valvular insertion causing left ventricular outflow tract obstruction. Patients with Noonan syndrome typically have preserved fertility and, given the success of cardiac surgery and medical management of heart failure in this population, are beginning to present more commonly as parturients in adulthood. Maternal physiologic changes during pregnancy introduce an added complexity to hemodynamic management and anesthetic considerations during labor and delivery. In this article, we present a case of a patient with Noonan syndrome with severe mitral stenosis, pulmonary valve insufficiency, and severe restrictive and obstructive pulmonary disease who presented preterm for delivery due to increased dyspnea at rest. Here we review the pathophysiology behind Noonan syndrome and peripartum management strategies in a patient with severe combined cardiac and pulmonary disease.

PHEOCHROMOCYTOMAS ARE rare neuroendocrine tumors that arise from both chromaffin cells in the adrenal medulla and sympathetic ganglion, or nonchromaffin cells in the parasympathetic ganglion. 1 Zhao B Zhou Y Zhao Y et al. Co-occurrence of pheochromocytoma-paraganglioma and cyanotic congenital heart disease: A case report and literature review. Front Endocrinol (Lausanne). 2018; 9: 165 Crossref PubMed Scopus (6) Google Scholar Pheochromocytomas arising from sympathetic tissue more commonly secrete catecholamines than those arising outside sympathetic tissue. 2 Lenders JW Eisenhofer G Mannelli M et al. Phaeochromocytoma. Lancet. 2005; 366: 665-675 Abstract Full Text Full Text PDF PubMed Scopus (1195) Google Scholar A strong association exists between cyanotic congenital heart disease and pheochromocytomas, with a higher- than- normal incidence seen in patients with cyanotic congenital heart disease (incidence reported as high as 2.5%) versus the normal hypertensive population prevalence of 0.2% to 0.6%. 1 Zhao B Zhou Y Zhao Y et al. Co-occurrence of pheochromocytoma-paraganglioma and cyanotic congenital heart disease: A case report and literature review. Front Endocrinol (Lausanne). 2018; 9: 165 Crossref PubMed Scopus (6) Google Scholar ,3 Lenders JW Duh QY Eisenhofer G et al. Pheochromocytoma and paraganglioma: An endocrine society clinical practice guideline. J Clin Endocrinol Metab. 2014; 99: 1915-1942 Crossref PubMed Scopus (1195) Google Scholar Chronic hypoxia has been speculated as a likely pathogenic mechanism related to abnormal activation of the hypoxic pathways located within the chromaffin cells. 4 Opotowsky AR Moko LE Ginns J et al. Pheochromocytoma and paraganglioma in cyanotic congenital heart disease. J Clin Endocrinol Metab. 2015; 100: 1325-1334 Crossref PubMed Scopus (43) Google Scholar , 5 Jochmanova I Yang C Zhuang Z et al. Hypoxia-inducible factor signaling in pheochromocytoma: Turning the rudder in the right direction. J Natl Cancer Inst. 2013; 105: 1270-1283 Crossref PubMed Scopus (111) Google Scholar , 6 Favier J. Pheochromocytomas: The (pseudo)-hypoxia hypothesis. Best Practice Res Clin Endocrinol Metab. 2010; 24: 957-968 Crossref PubMed Scopus (76) Google Scholar Although Fontan is intended to mitigate cyanosis, patients may be exposed to cyanosis before Fontan repair, and patients with failing Fontan physiology may become cyanotic due to fenestration, baffle leaks, and veno-venous collateral circulation. 7 Eagle SS Daves SM. The adult with Fontan physiology: Systematic approach to perioperative management for noncardiac surgery. J Cardiothorac Vasc Anesth. 2011; 25: 320-334 Abstract Full Text Full Text PDF PubMed Scopus (24) Google Scholar Further, excess catecholamines secreted by the pheochromocytoma can mimic and induce heart failure and arrhythmias in all patients, particularly those with Fontan physiology.

•DIAS is readily diagnosed by TEE but is more difficult to detect by MRI.•DIAS presents challenges for transseptal puncture.•Implications of DIAS for anticoagulation therapy are poorly defined.

BACKGROUND:Incomplete surgical left atrial appendage occlusion (S-LAAO) with a narrow neck has been shown to predict an increased rate of embolic stroke. Patients with a previously attempted S-LAAO were systematically excluded from all clinical trials of LAA closure devices. OBJECTIVE:The purpose of this study was to evaluate the feasibility of Watchman LAA device closure for patients referred with chronically incomplete S-LAAO. METHODS:A prospective single-arm feasibility cohort evaluated only subjects undergoing Watchman LAA closure following incomplete S-LAAO. Patients referred and implanted were followed in the Vanderbilt LAA Registry. Preprocedure computed tomographic angiography and transesophageal echocardiography (TEE) were performed to evaluate suitability for closure, with 45-day follow-up TEE postimplant. RESULTS:All attempted LAA closures after incomplete S-LAAO were successful (n = 6). Mean age was 76.3 ± 7 years. Mean CHADS2Vasc score was 3.8 ± 0.8, and HAS-BLED score was 3.5 ± 0.5. At 45-day follow up, all subjects had complete device seal with no thrombus on device and had transitioned to clopidogrel plus aspirin. Three subjects had narrow ostial necks with a maximum diameter ≤9 mm. In all cases, the 4.7-mm Watchman access sheath was able to cross the ostial stricture. Mean occluder size implanted was 28 ± 4 mm. Mean LAA dimension by TEE in the 45° and 135° views for depth was 31 mm and ostial diameter was 11 × 16 mm, below the minimum Watchman indication for use of 17 mm. No major intraoperative complications occurred. CONCLUSION:Watchman LAA closure seems to be feasible in patients with chronically incomplete S-LAAO, including subjects with a narrow neck ≤9 mm in width.

Anesthesiologists administer excess supplemental oxygen (hyper-oxygenation) to patients during surgery to avoid hypoxia. Hyper-oxygenation, however, may increase the generation of reactive oxygen species and cause oxidative damage. In cardiac surgery, increased oxidative damage has been associated with postoperative kidney and brain injury. We hypothesize that maintenance of normoxia during cardiac surgery (physiologic oxygenation) decreases kidney injury and oxidative damage compared to hyper-oxygenation.

As ventricular-assist devices (VADs) are increasingly employed in heart failure management, a leading cause of mortality, new literature is consistently published on less-invasive implantation techniques. Although early perioperative outcomes have been shown to be favorable with minimally invasive left thoracotomy (LT) approaches compared with conventional sternotomy (CS), studies comparing long-term outcomes are lacking. We set out to evaluate long-term follow up between LT and CS approach. In a single center, retrospective review, data on patients with similar demographic profiles were collected. HeartWare (HVAD) implantation was performed by either CS or LT. Analysis was performed on perioperative adverse outcomes, and 6 month postoperative adverse events. Primary objectives of the study included comparative outcomes of morbidity and mortality between both groups at 180 days postimplantation. Eighty-one (n = 81) bridge to transplant (BTT) patients underwent CS or LT HVAD implantation. Perioperative transfusion (p = 0.04) favored the LT cohort compared with CS, with a median of 6 units and 8 units transfused for each group, respectively. No survival difference was observed between both groups at 6 months postimplantation (p = 0.52). Clinical outcomes at an average of 6 month follow up showed no difference in adverse events, including common postoperative VAD complications such as infection and right heart failure. Miniaturization of LVAD size and improvement in technology has allowed expansion of interest in alternative surgical approaches for HVAD implantation. For BTT patients, no difference in early outcome was observed 6 months after implantation using a left LT versus CS technique.

Figure 1: Three-dimensional zoom acquisition en face view of the bioprosthetic tricuspid valve demonstrating the valve sewing ring with the triangular shaped retained valve holder.Figure 2: Three-dimensional zoom acquisition rotated to show the anterior to posterior side view of tricuspid bioprosthetic annulus. The retained valve holder extends above the annular plane. RA = right atrium; RV = right ventricle.Figure 3: Retained valve holder, 29-mm Sapien transcatheter valve (Edwards Lifesciences), and 11 × 7 mm Amplatzer Vascular Plug (St. Jude Medical) removed during surgery are shown.A 54-year-old patient with 2 previous tricuspid valve (TV) replacements performed at a different institution presented with worsening symptoms of chronic congestive heart failure, including lower extremity edema. Preoperative echocardiography demonstrated severe bioprosthetic TV stenosis with a mean gradient of 10 mm Hg, trace tricuspid regurgitation, as well as P2 segment flail of the mitral valve with severe eccentric mitral regurgitation. Because of the perceived difficulty with a third tricuspid procedure, the surgical plan included initial percutaneous deployment of a 29-mm Sapien (Edwards Lifesciences, Irvine, CA) transcatheter heart valve-in-valve in the tricuspid position followed by a minimally invasive mitral valve repair through a right thoracotomy in a hybrid operating room. Intraoperative transesophageal echocardiography of the bioprosthetic TV was performed, demonstrating severely restricted leaflet motion on 2-dimensional (2D) images (Supplemental Digital Content 1, Video 1, https://links.lww.com/AA/B251), mild prosthetic tricuspid regurgitation with color flow Doppler, and lack of visible leaflets on 3-dimensional (3D) images (Supplemental Digital Content 2, Video 2, https://links.lww.com/AA/B252), with apparent heavy calcification of the prosthetic valve on 2D and 3D images (Figs. 1 and 2). Deployment of the transcatheter Sapien valve was complicated by the inability to place the guidewire in the central axis of the prosthetic valve. Failure to completely expand the Sapien valve resulted in severe paravalvular leak outside the Sapien valve but inside the previously placed prosthetic valve (Supplemental Digital Content 3, Video 3, https://links.lww.com/AA/B253). The maximal mean pressure gradient through the Sapien valve was 8 mm Hg at a heart rate of 74 bpm. Placement of an Amplatzer plug (St. Jude Medical, Saint Paul, MN) did not improve the paravalvular leak. Because of the change in the surgical plan, the surgery was cancelled and the patient was brought back to the cardiac operating room on another day. For the second operation, a right anterior thoracotomy was performed. Upon opening the right atrium, it was discovered that the valve holder of the bioprosthetic TV had been left in place from the previous surgery 3 years earlier. The presence of the valve holder explained the presenting functional TV stenosis, the impression of severe valvular thickening and calcification, as well as the subsequent failure to fully expand the Sapien valve. The latter had been deployed in the space between the holder and the annulus of the bioprosthesis resulting in severe paravalvular leak (relative to the Sapien valve). The valve holder, Sapien valve, and Amplatzer plug (Fig. 3) were removed and the TV replaced with a new bioprosthetic valve in the tricuspid position. The patient provided written consent for this publication. DISCUSSION The differential diagnosis for bioprosthetic valve stenosis includes pannus formation, structural valve deterioration, and, infrequently, thrombus formation.1,2 A retained valve holder causing bioprosthetic valve stenosis is a rare and likely underreported event. We failed to make the correct diagnosis of a retained valve holder because the diagnosis is unusual and no reports describing the echocardiographic characteristics of this condition have been published. We suggest adding this to the differential diagnosis for bioprosthetic valve stenosis and describe some of the echocardiographic and clinical findings (Table 1).Table 1: Echocardiographic and Clinical Characteristics of a Retained Valve HolderWith 2D imaging, the echocardiographic appearance of the valve was similar to that of structural valve deterioration with severely calcified leaflets and reduced mobility. In hindsight, the appearance of “calcification” extending beyond the tricuspid annulus was an indicator of the unusual diagnosis. Structural bioprosthetic valve deterioration results in thickened leaflets with reduced mobility, but extension of calcium is uncommon beyond the bioprosthetic annulus.2 With color flow Doppler, the degree of tricuspid regurgitation was less than might be expected. This may be explained by the fact that, although the valve holder reduces the effective orifice area of the valve (and increases the mean pressure gradient), the noncalcified valve leaflets can still close (albeit closing against the valve holder). Echocardiography can detect prosthetic TV stenosis with spectral Doppler-derived parameters such as an E-wave velocity >1.7 m/s, mean gradient >6 mm Hg, or pressure half-time >230 milliseconds suggesting valve stenosis.1 Such findings should ideally have been made before leaving the operating room or before discharge from hospital on the previous occasion because American Society of Anesthesiologists/Society of Cardiovascular Anesthesiologists guidelines recommend the use of transesophageal echocardiography in all adult open heart surgeries.3 On 3D imaging, the retained valve holder prevented the display of the leaflets. However, 3D imaging did show the valve holder which appears triangular in shape (“Mercedes sign with central orifice”) and extends above the annular sewing ring. The central orifice in the en face 3D view is also an unusual finding, representing the attachment site for the valve holder handle. The retained valve holder prevented the transcatheter guidewire and balloon from being positioned centrally in the bioprosthetic valve. The severe paravalvular leak, after Sapien valve deployment, resulted from failure to fully expand the Sapien valve within the bioprosthetic annulus because of constraint by the valve holder. Finally, a clue to the unusual diagnosis is the fact that the patient presented within 3 years of valve implantation. Although younger age at implantation is associated with a higher occurrence of structural valve deterioration requiring reoperation, such early failure of a stented bioprosthesis is infrequent, because freedom from structural valve failure is 70% to 90% at 10 years and 50% to 80% at 15 years.2,4 Specifically, the linearized incidence of structural bioprosthetic TV deterioration is 0.50% per patient-year, suggesting that valve failure from structural valve deterioration within 3 years is unlikely even in this young patient.5 A retained valve holder should be a “never event.” Adding the valve holder to the surgical count may help prevent this event from occurring. Next, the valve holder is radiolucent and is not visible on fluoroscopy. Making the valve holder radio-opaque will alert the physician, although this will most likely only occur in the postoperative period. In conclusion, the specific 3D echocardiographic characteristics, in contrast to the nonspecific 2D, color, and spectral Doppler characteristics can help to differentiate a retained valve holder from structural valve deterioration. Clinician’s Key Teaching Points By Kent H. Rehfeldt, MD, Kimberly Howard-Quijano, MD, and Martin J. London MD The differential diagnosis for bioprosthetic tricuspid valve stenosis includes pannus ingrowth, degenerative changes with calcification, or, less frequently, thrombotic occlusion. Although bioprosthetic tricuspid prosthesis degeneration occurs more quickly in younger patients, approximately 70% to 90% of patients remain free of structural failure 10 years after implantation. Bioprosthetic tricuspid valve stenosis is diagnosed on the basis of 2D or 3D echocardiographic findings of thickened or calcified leaflets with reduced mobility. Spectral Doppler findings include an E-wave velocity >1.7 m/s, a mean diastolic gradient >6 mm Hg, and a pressure half-time >230 milliseconds. In this case, a patient with a bioprosthetic tricuspid valve implanted 3 years prior presented with worsening heart failure symptoms including lower extremity edema. Echocardiography revealed prosthetic tricuspid stenosis, with a mean diastolic gradient of 10 mm Hg. Placement of a percutaneous, valve-in-valve prosthesis was complicated by the inability to position a guidewire in the center of the previously placed prosthesis, failure to completely expand the transcatheter valve, and severe paravalvular regurgitation after deployment. A subsequent open heart procedure revealed a retained tricuspid prosthesis valve holder from the previous operation. Although the diagnosis of a retained valve holder was not recognized by echocardiography, several unusual findings noted during the transesophageal echocardiography examination included the inability to visualize bioprosthetic leaflets, apparent calcification that extended beyond the tricuspid annulus, and a central orifice in the en face 3D view that represented the site of attachment of the valve holder handle. In addition, stenotic degeneration of a bioprosthesis 3 years after implantation is unusual, even in a younger patient. DISCLOSURES Name: Jeremy M. Bennett, MD. Contribution: This author drafted the manuscript. Attestation: Jeremy M. Bennett approved the final manuscript. Name: Robert Deegan, MBChB, BAO, PhD, FFARCSI. Contribution: This author made critical revisions to the manuscript. Attestation: Robert Deegan approved the final manuscript. Name: Simon Maltais, MD, PhD. Contribution: This author made critical revisions to the manuscript. Attestation: Simon Maltais approved the final manuscript. Name: Mias Pretorius, MBChB, MSCI. Contribution: This author obtained the ultrasound images and made critical revisions to the manuscript. Attestation: Mias Pretorius approved the final manuscript and is the archival author. This manuscript was handled by: Martin J. London, MD.

BACKGROUND: Minimally invasive left thoracotomy (MILT) and off-pump implantation strategies have been anecdotally reported for implantation of the HeartWare ventricular assist device (HVAD). We analyzed our experience with off-pump MILT implantation techniques and compared early in-hospital outcomes with conventional on-pump sternotomy (CS) implantation strategy.METHODS: Between January 2013 and February 2014, 51 patients underwent HVAD implantation and were included in this study. Thirty-three patients had CS, whereas 18 patients underwent offpump MILT. To compare outcomes of these techniques, a multivariate analysis using propensity score modeling was performed after adjusting for age, INTERMACS, Kormos and Leitz-Miller (LM) scores.RESULTS: Mean age at implant was 57 (range 18 to 69) years, and overall in-hospital mortality was 8%. Univariate analysis revealed a statistically significant reduction in days on inotropes (p = 0.04), and a trend toward reduced intra-operative blood product administration (p = 0.08) in the MILT group. There was no difference in intensive-care-unit length of stay (p = 0.5), total length of stay (p = 0.76), post-operative blood product administration (p = 0.34) and total time on mechanical ventilation (p = 0.32). After adjusting for age, INTERMACS profile and Kormos and LM scores, no statistically significant differences were observed between the MILT and CS groups.CONCLUSIONS: An off-pump MILT implantation strategy can be utilized as a safe surgical approach for patients undergoing HVAD implantation. Further large collaborative studies are needed to identify advantages of the MILT approach. Published by Elsevier Inc.

BACKGROUND The wastage of red blood cell (RBC) units within the operative setting results in significant direct costs to health care organizations. Previous education-based efforts to reduce wastage were unsuccessful at our institution. We hypothesized that a quality and process improvement approach would result in sustained reductions in intraoperative RBC wastage in a large academic medical center.STUDY DESIGN AND METHODS Utilizing a failure mode and effects analysis supplemented with time and temperature data, key drivers of perioperative RBC wastage were identified and targeted for process improvement.RESULTS Multiple contributing factors, including improper storage and transport and lack of accurate, locally relevant RBC wastage event data were identified as significant contributors to ongoing intraoperative RBC unit wastage. Testing and implementation of improvements to the process of transport and storage of RBC units occurred in liver transplant and adult cardiac surgical areas due to their history of disproportionately high RBC wastage rates. Process interventions targeting local drivers of RBC wastage resulted in a significant reduction in RBC wastage (p<0.0001; adjusted odds ratio, 0.24; 95% confidence interval, 0.15-0.39), despite an increase in operative case volume over the period of the study. Studied process interventions were then introduced incrementally in the remainder of the perioperative areas.CONCLUSIONS These results show that a multidisciplinary team focused on the process of blood product ordering, transport, and storage was able to significantly reduce operative RBC wastage and its associated costs using quality and process improvement methods.

In the past less invasive and OFF-pump implantation strategies have been anecdotally reported using the HeartWare ventricular assist device (HVAD). We describe our experience with a left thoracotomy minimally invasive OFF-pump implantation technique (OFF-P), and compare early in-hospital outcomes to patients undergoing conventional ON-pump implantation (ON-P). Between January 2013 and November 2013, 49 patients underwent HVAD implantation, of whom seven (6 males, 85.7%) were approached with OFF-P, while 42 (34 males, 81%) were implanted using ON-P. Multivariate analysis was used to compare surgical techniques after adjusting for age, INTERMACS, Kormos and Lietz-Miller scores, using propensity score modeling. All patients were implanted as a bridge-to-transplantation. Overall survival was 92% (n=45). All patients in the OFF-P survived to discharge. When compared to ON-P, OFF-P patients had higher Kormos scores (0.58 vs. 0.41, p=0.04), while all other preoperative characteristics were comparable (all p>0.05). Intraoperative and postoperative blood product requirement averaged 1.71±0.95 and 0.86±1.2 units respectively for OFF-P, versus 7.55±11.8 and 3.54±8.1 units for ON-P (p=0.35 and p=0.48). Days on inotropes averaged 4.1±4.0 for OFF-P (6.2±3.6 for ON-P, p=0.15). Mean ICU length of stay (LOS) and total in-hospital LOS for OFF-P was 7.3±5.2 and 13.6±4.1 days, respectively, compared to 6.6±5.2 and 13.4±5.5 for ON-P (p=0.54 and p=0.65). Propensity score multivariate analysis revealed comparable early outcomes between groups (Table 1). A minimally invasive left thoracotomy OFF-pump implantation strategy can be safely utilized in selected patients undergoing HVAD implantation. Despite higher Kormos score in OFF-P, encouraging comparable outcomes between the two techniques were observed. Further collaborative studies are needed to identify differences between implant strategies.Tabled 1

ENDOCRINOPATHIES may have a significant impact on the cardiovascular system. The effects may be humoral or structural and may contribute to significant morbidity and mortality. This article examines and specifically focuses on the cardiovascular manifestations of thyroid dysfunction, acromegaly, pheochromocytomas, neuroendocrine tumors, and adrenal cortical dysfunction in addition to the cardiovascular effects of exogenously administered androgenic anabolic steroids. Diabetes mellitus, which has been covered extensively elsewhere, is not included in this review. For discussion of the cardiovascular manifestations of that condition, as well as for general information regarding the perioperative management of patients with endocrine diseases, the reader is referred to standard reference texts and general literature reviews. 1 Barash P.G. Stoelting R.K. Cahalan M.K. Clinical Anesthesia. (ed 6). Lippincott Williams & Wilkins, Philadelphia, PA2009 Google Scholar , 2 Yao S.F. Fonte M.L. Malhotra V. Yao and Artusio's Anesthesiology: Problem-Oriented Patient Management. (ed 6). Lippincott Williams & Wilkins, Philadelphia, PA2007 Google Scholar

OBJECTIVEIn this study, the therapeutic use of pacing pulmonary artery catheters in association with minimally invasive cardiac surgery was evaluated.DESIGNA retrospective study.SETTINGSA single institutional university hospital.PARTICIPANTSTwo hundred twenty-four consecutive patients undergoing minimally invasive cardiac surgery through a small (5-cm) right anterolateral thoracotomy using fibrillatory arrest without aortic cross-clamping.MEASUREMENTS AND MAIN RESULTSTwo hundred eighteen patients underwent mitral valve surgery (97%) alone or in combination with other procedures. Six patients underwent other cardiac operations. In all patients, the pacing pulmonary artery catheter was used intraoperatively to induce ventricular fibrillation during the cooling period, and in the postoperative period it also was used in 37 (17%) patients who needed to be paced, mainly for bradyarrhythmias (51%). There were no complications related to the insertion of the catheters. Six (3%) patients experienced a loss of pacing capture, and 2 (1%) experienced another complication requiring the surgical removal of the catheter. Seven (3%) patients needed postoperative implantation of a permanent pacemaker.CONCLUSIONSIn combination with minimally invasive cardiac surgery, pacing pulmonary artery catheters were therapeutically useful to induce ventricular fibrillatory arrest intraoperatively and for obtaining pacing capability in the postoperative period. Their use was associated with a low number of complications.

TAKOTSUBO CARDIOMYOPATHY (idiopathic or transient left ventricular apical ballooning syndrome [ABS]) is a reversible condition frequently precipitated by a stressful trigger that clinically mimics an acute ST-elevation myocardial infarction. 1 Brenner Z.R. Powers J. Takotsubo cardiomyopathy. Heart Lung. 2008; 37: 1-7 Abstract Full Text Full Text PDF PubMed Scopus (35) Google Scholar Characteristically, hypokinesis or akinesis occurs in the mid and apical segments of the left ventricle in the absence of epicardial coronary lesions. Preserved (or hyperdynamic) function of the basal myocardial segments results in apical ballooning, assuming the shape of a Japanese pot used to catch octopus (a takotsubo).

Developing new strategies to improve patient safety and risk reduction is fundamental to hospital and patient success. Currently, there is a tendency in hospital safety management to focus solely on human error rather than organizational and educational causes that contribute to medical accidents. Although health care providers are the primary safety systems in medical facilities, there must be a more global, perhaps automated, approach using modern technology to prevent or reduce medical mishaps. Herein, we present an oxygenation failure with root cause analysis that prompted a new oxygenation safety algorithm and multi-service training initiative.

New-onset mitral regurgitation after routine coronary revascularization is most often the result of ischemia and may be secondary to acute graft dysfunction. After securing the diagnosis, the surgeon must speculate as to the cause (eg, myocardial stunning, subendocardial ischemia, poor myocardial protection, or thrombosis, kinking, or anastomotic obstruction of the graft). Currently available intraoperative diagnostic tools include transesophageal echocardiography, flow meters, and manual palpation of grafts, all of which are limited. Surgical graft revision invariably requires a second period of cardiopulmonary bypass and aortic crossclamping. We describe a patient in whom new-onset severe mitral regurgitation was diagnosed by intraoperative echocardiography in our new “hybrid” operating suite. In this environment, a combined catheterization laboratory and operating room, and the use of intraoperative completion angiography, crystallized the cause of our patient’s mitral regurgitation and provided a rapid solution to the problem without the need for another period of cardiopulmonary bypass or aortic clamping. A 76-year-old man was referred for coronary artery bypass grafting. He had a history of myocardial infarction 5 months before surgery, for which he underwent percutaneous coronary intervention to the left anterior descending artery. He recovered well, but later presented with anginal symptoms, severe 3-vessel disease, and in-stent restenosis. Preoperative transthoracic and transesophageal echocardiography documented trace mitral regurgitation. The patient underwent uneventful coronary artery bypass grafting of the left internal thoracic artery to left anterior descending artery, saphenous vein to diagonal artery, and saphenous vein to obtuse marginal artery. Intraoperative conventional biplanar completion angiography demonstrated patent grafts to the diagonal and left anterior descending arteries. However, the obtuse marginal vein graft had an eccentric 70% stenosis in the midthird and a valve distally that produced a 60% diameter stenosis (Figure 1). Contemporaneously, intraoperative transesophageal echocardiography demonstrated new-onset severe mitral regurgitation with pulmonary vein flow reversal. This was thought to be the result of regional/papillary muscle ischemia from the obtuse marginal vein graft dysfunction. However, visual graft inspection revealed no obvious abnormality. While the patient was in the hybrid suite, with the chest open, drug-eluting stents were deployed at each graft lesion leaving a 0% residual stenosis and Thrombolysis in Myocardial Infarction III flow, with recruitment of additional collaterals on the lateral wall (Figure 2). Immediately after this, transesophageal echocardiography showed complete resolution of the mitral regurgitation and normalization of pulmonary vein flow.Figure 2Intra-operative completion angiogram after percutaneous intervention with improved runoff in recruited collaterals.View Large Image Figure ViewerDownload (PPT) The “hybrid” approach has recently been shown to reduce mortality associated with complex cardiac procedures.1Byrne J.G. Leacche M. Unic D. Rawn J.D. Simon D.I. Rogers C.D. et al.Staged initial percutaneous coronary intervention followed by valve surgery (“hybrid approach”) for patients with complex coronary and valve disease.J Am Coll Cardiol. 2005; 45: 14-18Abstract Full Text Full Text PDF PubMed Scopus (99) Google Scholar These results have prompted the creation of hybrid operating rooms in which routine intraoperative completion angiograms can be performed for quality assurance. Our patient exemplifies the need for, and value of, “sighted” surgery through the use of postprocedure imaging. In the hybrid operating room, immediate intraoperative completion angiography allows critical assessment of graft patency, including both conduit characteristics and anastomotic quality. Intraoperative correction of these lesions may aid in avoiding early graft failure, which is currently reported at 15% at 1 year.2Goldman S. Zadina K. Moritiz T. Ovitt T. Sethi G. Copeland J.G. et al.Long-term patency of saphenous vein and internal mammary artery grafts after coronary artery bypass surgery.J Am Coll Cardiol. 2004; 44: 2149-2156Abstract Full Text Full Text PDF PubMed Scopus (716) Google Scholar A second unique advantage of the hybrid operating environment is in providing less-invasive therapeutic options. As in our patient, surgical graft revision would have required a second period of cardiopulmonary bypass and aortic clamping, and this was avoided by electing to perform a less-invasive percutaneous intervention. This resulted in a dramatic improvement in the graft flow and distal runoff with recruitment of collaterals and immediate resolution of the patient’s mitral regurgitation. Moreover, the hybrid environment will undoubtedly lead to more liberal use of minimally invasive valve operations combined with percutaneous coronary interventions and combined surgical and percutaneous revascularization techniques.3Stahl K. Boyd W.D. Vassiliades T.A. Karamanoukian H.L. Hybrid robotic coronary artery surgery and angioplasty in multivessel coronary artery disease.Ann Thorac Surg. 2002; 74: S1358-S1362Abstract Full Text Full Text PDF PubMed Google Scholar

We report a case in which a TandemHeart (CardiacAssist, Pittsburgh, PA) percutaneous left ventricular assist device (pVAD) was placed for temporary circulatory support in a 20-yr-old female who presented with cardiogenic shock secondary to viral myocarditis. Despite inotropic support with milrinone 0.5 μg/kg/min, norepinephrine 12 μg/min, and an intraaortic balloon pump, her cardiac index remained <2.0 L/min/m2 and she developed nonoliguric acute renal failure. She was taken to a cardiac operating room with full cardiac catheterization capabilities for placement of a pVAD. She received general endotracheal anesthesia and was monitored with a pulmonary artery catheter, arterial line, and transesophageal echocardiography (TEE). The TandemHeart System consists of a centrifugal pump, a system controller, and a cannula set (1). Femoral venous access was obtained percutaneously and a guidewire was passed into the right atrium under fluoroscopic guidance. The midesophageal (ME) bicaval view confirmed the presence of the guidewire in the right atrium. A Mullins guide catheter (Medtronic, Minneapolis, MN) was then positioned to the superior vena cava, the guidewire removed, and a transseptal needle (Cook, Bloomington, IN) loaded to a position within the catheter near the tip. Next, the fossa ovalis was identified (thinnest portion of the interatrial septum) using the ME aortic valve short axis view (40°–50°). The transseptal needle-dilator-sheath unit was manipulated under echocardiographic and fluoroscopic guidance to the region of the fossa ovalis. TEE allowed observation of "tenting" or billowing of the fossa ovalis into the left atrium (LA) followed by transseptal puncture (Fig. 1; also please see video clip available at www.anesthesia-analgesia.org). TEE visualization of the needle tip is critical to prevent puncture of the aorta or atrial wall (2). After confirming successful transseptal puncture, the Mullins tip was extended over the needle tip within the LA. With the Mullins sheath fixed, the transseptal needle was then exchanged for a guidewire, which was then advanced into the left upper pulmonary vein. This was visualized in the ME four-chamber view with the transducer rotated to 70°. The puncture hole was then dilated using a two-stage dilator. Advancement of a sheath and dilator across the septum should be accomplished over a guidewire directed to a pulmonary vein for optimal safety. The radiopaque transseptal cannula was advanced through the femoral vein across the atrial septum into the LA. The guidewire was first removed followed by removal of the obturator, once proper positioning of the cannula in the LA was verified by both fluoroscopy and TEE. TEE confirmed that all the inflow holes of the transseptal cannula were on the LA side (Fig. 2). An arterial cut-down was necessary to place the femoral cannula. The arterial and venous cannulae were then connected to the centrifugal pump. The pump pulls oxygenated blood from the LA and returns it to the systemic arterial circulation, thus initiating partial left heart bypass. pVAD flows were initiated at 3 L/min. Color Doppler TEE of the transseptal cannula demonstrated proper flow with no entrainment of blood from the right atrium. A TEE evaluation excluded pericardial tamponade.Figure 1.: Two-dimensional midesophageal short axis view of aortic valve. Arrows indicate transseptal puncture of the atrial septum. RA indicates right atrium; LA indicates left atrium; AV indicates aortic valve.Figure 2.: Two-dimensional midesophageal short axis view of aortic valve. Arrows indicate TandemHeart transseptal cannula in place. RA indicates right atrium; LA indicates left atrium; AV indicates aortic valve.Because of a diagnosis of heparin-induced thrombocytopenia, anticoagulation was provided with argatroban to maintain the activated partial thromboplastin time between 60 and 80 s. The patient's cardiac index improved to 3 L/min/m2 and the acute renal failure resolved. Five days later she underwent an orthotopic heart transplant and was discharged from hospital on postoperative day 14. Intraoperative TEE assists in transseptal puncture, placement of the transseptal cannula, and diagnosis of potential complications associated with this procedure.

The regulation of vascular beta-adrenoceptor responses in humans has been studied in vivo in both arteries and veins. Because venous responses can be studied less invasively than arterial responses, they are an attractive substitute-for the measurement of arterial responses, provided that venous responses are representative of responses in resistance arteries. However, although venous, particularly hand vein response, has been extensively studied, arterial and venous beta-adrenergic sensitivities, in the same individuals, have not been compared. Measures of venous and arterial beta-adrenergic sensitivities were compared in 10 healthy normotensive subjects. Forearm blood flow, after administration of increasing doses of isoproterenol into the brachial artery, was measured by strain-gauge plethysmography and was used for determination of arterial beta-adrenoceptor sensitivity, expressed as the IP500 (the dose of isoproterenol resulting in a fivefold [500%] increase in baseline forearm blood flow). Venous sensitivity to isoproterenol, expressed as the IP15 (the dose of isoproterenol resulting in 15% venodilation), was measured in a dorsal hand vein using the linear variable differential transformer. Administration of isoproterenol into the hand vein and brachial artery resulted in venodilation and increased forearm blood flow, respectively. However, there was no correlation between the measures of venous (log IP15) and arterial (log IP500) measures of vascular beta-adrenergic sensitivity (r=-.12, P=.74). We conclude that since arterial and venous sensitivities to isoproterenol in healthy white men did not correlate, venous and arterial beta-adrenergic responses are regulated differently and that studies examining vascular beta-adrenoceptor sensitivity would most appropriately be performed in a vessel representative of the vascular bed of interest.

BACKGROUND:Presynaptic receptors control norepinephrine (NE) release. It has been hypothesized that epinephrine stimulates prejunctional beta 2-adrenergic receptors to facilitate NE release from sympathetic nerve endings, and therefore, presynaptic receptors controlling NE release are potential therapeutic targets to limit the adverse effects of excess sympathetic stimulation during anesthesia. We have previously demonstrated beta 2-adrenergic receptor-augmented release of NE in the human forearm and have shown that halothane inhibits sympathetic activity in vivo by decreasing the NE spillover rate into plasma. The goal of the current study was to determine the effect of halothane on beta 2-adrenergic receptor-augmented NE release in a canine hind-limb experimental model.METHODS:Seven female dogs were studied awake and during halothane anesthesia (1.0 minimum alveolar concentration). A trace dosage of [3H]NE (15 microCi over a 1-min period and 0.6 microCi/min thereafter) was infused into the femoral vein. Before and during femoral arterial administration of isoproterenol at two dosages (30 and 80 mg/min), hind-limb blood flow was measured by an ultrasonic flow probe and hind-limb NE spillover by an isotope dilutional technique.RESULTS:In awake dogs, isoproterenol significantly increased hind-limb blood flow and NE spillover into the hind limb. Halothane had no effect on baseline or isoproterenol-stimulated hind-limb blood flow (a postjunctional beta 2 effect) but significantly inhibited the isoproterenol-induced increase in hind-limb NE spillover (a prejunctional beta 2 effect).CONCLUSIONS:The isoproterenol-mediated increase in NE release is inhibited by halothane anesthesia, indicating that halothane inhibits prejunctional beta 2-adrenergic receptor regulation of NE release.