The chapter reviews the knowledge about the role of echocardiography for managing LVAD therapy including candidate selection, planning of implant surgery, intraoperative guidance of pump optimization and monitoring of right ventricular (RV) function, postoperative surveillance of LVAD and RV function, as well as evaluation of myocardial recovery.

Right ventricular pressure overloading [RVPO] with secondary maladaptive RV remodeling and progressive myocardial dysfunction in patients with pulmonary hypertension associated with left-sided heart diseases [PH-LHDs] and in those with pulmonary arterial hypertension [PAH] still remains one of the most complex challenges in cardio-pulmonary medicine. Despite the advances in the optimization of diagnostic tools and the expansion of treatment options, there is still a great need for further research to gain a better understanding of the major pathophysiological mechanisms involved in both the RV responses to PO and to find new possibilities to stop the progression of the alterations inside the pulmonary arterial circulation [PAC]. This article summarizes current knowledge about the particularities of the RV structural and functional responses to abnormal PO and also provides an overview of the benefits and limitations of the currently available tools for clinical evaluations of the RV adaptability to high afterload. A major focus of this review relates to the possibilities for obtaining evidence about the existence of a still remaining adaptability to a normal afterload in an over-burdened RV, in case of abolition of the pathological PO and, in this regard, to also evaluate the clinical usefulness of the RV adaptability estimation for certain critical therapeutic decisions. Among the most important conclusions of this updated overview are: 1. Whereas single parameters are insufficiently reliable for the evaluation of RV dysfunction and for predictions of its prognostic relevance across the whole spectrum of RVPO, properly selected and integrated multiparametric approaches had meanwhile unequivocally proved that they can usually become sufficiently reliable. 2. Multiparametric approaches can substantially improve the prediction of a preserved RV responsiveness to the abolition of its steady PO by reversal of RV maladaptive remodeling and by the normalization of RV pump function. Such a prediction, which can be decisive for therapeutic decision-making especially in candidates for ventricular assist device [LVAD] implantation or thoracic organ transplantation, can have a crucial impact on patient survival. 3. The complex and temporally highly variable interactions between certain structural and functional changes in both the PAC and in the hemodynamic overloaded right-sided heart, as well as between the two ventricles, can often hamper the interpretation of certain changes in the measured parameters and even relevantly alter their reliability. Additionally, the progressive aggravation of a secondary tricuspid regurgitation [TR] has a particularly high negative (often also misleading) impact on the diagnostic and prognostic relevance of RVPO evaluations.

Left ventricular ejection fraction (LVEF) is still used as a key determinant of LV function and timing in mitral regurgitation (MR) intervention in patients with chronic primary MR, although its load dependency and its misleading overestimation of LV pump function in the presence of MR are generally accepted [1]. Even the evidence that the easily measurable forward LVEF (i.e. LV forward stroke volume/end-diastolic volume) can be independently associated with life-threatening aggravation of MR in patients with nearly identical total LVEF and LV global longitudinal strain values [2,3], has not changed that opinion.

Regardless of whether pulmonary hypertension (PH) results from increased pulmonary venous pressure in left-sided heart diseases or from vascular remodeling and/or obstructions in pre-capillary pulmonary vessels, overload-induced right ventricular (RV) dysfunction and its final transition into right-sided heart failure is a major cause of death in PH patients. Being particularly suited for non-invasive monitoring of the right-sided heart, echocardiography has become a useful tool for optimizing the therapeutic decision-making and evaluation of therapy results in PH. The review provides an updated overview on the pathophysiological insights of heart-lung interactions in PH of different etiology, as well as on the diagnostic and prognostic value of echocardiography for monitoring RV responses to pressure overload. The article focuses particularly on the usefulness of echocardiography for predicting life-threatening aggravation of RV dysfunction in transplant candidates with precapillary PH, as well as for preoperative prediction of post-operative RV failure in patients with primary end-stage left ventricular (LV) failure necessitating heart transplantation or a LV assist device implantation. In transplant candidates with refractory pulmonary arterial hypertension, a timely prediction of impending RV decompensation can contribute to reduce both the mortality risk on the transplant list and the early post-transplant complications caused by severe RV dysfunction, and also to avoid combined heart-lung transplantation. The review also focuses on the usefulness of echocardiography for monitoring the right-sided heart in patients with acute respiratory distress syndrome, particularly in those with refractory respiratory failure requiring extracorporeal membrane oxygenation support. Given the pathophysiologic particularity of severe acute respiratory syndrome coronavirus (SARS-CoV-2) infection to be associated with a high incidence of thrombotic microangiopathy-induced increase in the pulmonary resistance, echocardiography can improve the selection of temporary mechanical cardio-respiratory support strategies and can therefore contribute to the reduction of mortality rates. On the whole, the review aims to provide a theoretical and practical basis for those who are or intend in the future to be engaged in this highly demanding field.

Speckle-tracking echocardiography (STE) parameters are an integral part of the assessment of left ventricular (LV) function. We aimed to evaluate established and novel STE parameters of LV diastolic function and their prognostic role in patients with LV anteroapical aneurysm undergoing surgical ventricular repair (SVR). We retrospectively examined the data of 137 patients with anteroapical LV aneurysm who underwent SVR. In 27 patients, the correlation of STE parameters with invasive hemodynamic parameters was evaluated. Preoperative echocardiographic parameters were assessed for their association with outcome, defined as all-cause mortality, LV assist device implantation, or heart transplantation. The late diastolic strain rate (GLSRa) showed a stronger correlation with mean pulmonary artery pressure (r = - 0.75, p < 0.001) than all other parameters. GLSRa was also significantly correlated with mean pulmonary capillary wedge pressure and LV end-diastolic pressure. In the multivariate model, GLSRa and the ratio of early diastolic filling velocity to GLSRa demonstrated incremental prognostic value in addition to clinical and echocardiographic parameters. Patients with GLSRa < 0.59 s-1 had significantly shorter event-free survival than those with GLSRa > 0.59 s-1 (6.7 vs. 10.9 years, p < 0.001). Peak reservoir left atrial strain showed a weaker association with hemodynamic parameters and outcome compared to GLSRa. In patients with LV aneurysm, late diastolic strain rate and left atrial strain can be used for the assessment of LV diastolic function and have a predictive value for the outcome after surgical ventricular restoration.

I read with interest the article by Sun et al.,1Sun K. Cedarbaum E. Hill C. et al.Association of right ventricular dilation on echocardiogram with in-hospital mortality among patients Hospitalized with COVID-19 compared with bacterial pneumonia.J Am Soc Echocardiogr. 2023; 36: 558-562Abstract Full Text Full Text PDF Scopus (1) Google Scholar which found that right ventricular (RV) dilation revealed by the first transthoracic echocardiogram (TTE) performed early (day 2 [1-5]) after admission was associated with in-hospital mortality among patients with SARS-CoV-2 but not in those with bacterial pneumonia, although RV dilation was similarly prevalent in those 2 patient groups. Rather surprisingly, in contrast to RV dilation, RV dysfunction revealed by the first TTE appeared not to be associated with in-hospital mortality. The high incidence of extensive pulmonary thrombotic microangiopathy associated with increased resistance in the pulmonary circulation and frequent afterload mismatch-induced RV failure is a distinctive feature of COVID-19-related acute respiratory distress syndrome and also a major cause for the particularly high mortality associated with SARS-CoV-2 pneumonia.2Dandel M. Heart-lung interactions in COVID-19: prognostic impact and usefulness of bedside echocardiography for monitoring of the right ventricle involvement.Heart Fail Rev. 2022; 27: 1325-1339Crossref PubMed Scopus (8) Google Scholar,3Chotalia M. Ali M. Alderman J.E. et al.Right ventricular dysfunction and its association with mortality in Coronavirus Disease 2019 acute respiratory distress syndrome.Crit Care Med. 2021; 49: 1757-1768Crossref PubMed Scopus (28) Google Scholar As soon as the compensatory responses of the dilated RV are exhausted, the RV becomes unable to preserve an adequate forward blood flow, and further aggravation of RV dysfunction can evolve into a major risk factor for mortality.3Chotalia M. Ali M. Alderman J.E. et al.Right ventricular dysfunction and its association with mortality in Coronavirus Disease 2019 acute respiratory distress syndrome.Crit Care Med. 2021; 49: 1757-1768Crossref PubMed Scopus (28) Google Scholar Pressure overload–induced RV dysfunction is recognized as a major cause of death for patients with COVID-19-related acute respiratory distress syndrome.2Dandel M. Heart-lung interactions in COVID-19: prognostic impact and usefulness of bedside echocardiography for monitoring of the right ventricle involvement.Heart Fail Rev. 2022; 27: 1325-1339Crossref PubMed Scopus (8) Google Scholar,4Dandel M. Pathophysiology of COVID-19-associated acute respiratory distress syndrome.Lancet Respir Med. 2021; 9: e4Abstract Full Text Full Text PDF PubMed Scopus (16) Google Scholar The simultaneous detection of RV dilation and dysfunction by TTE performed on median day 6 (3-10) after admission to intensive care units appeared independently associated with in-hospital mortality.3Chotalia M. Ali M. Alderman J.E. et al.Right ventricular dysfunction and its association with mortality in Coronavirus Disease 2019 acute respiratory distress syndrome.Crit Care Med. 2021; 49: 1757-1768Crossref PubMed Scopus (28) Google Scholar Early identification of patients with increasing COVID-19-related RV hemodynamic overloading can facilitate the selection of the most appropriate management, which can be decisive for their survival.2Dandel M. Heart-lung interactions in COVID-19: prognostic impact and usefulness of bedside echocardiography for monitoring of the right ventricle involvement.Heart Fail Rev. 2022; 27: 1325-1339Crossref PubMed Scopus (8) Google Scholar,4Dandel M. Pathophysiology of COVID-19-associated acute respiratory distress syndrome.Lancet Respir Med. 2021; 9: e4Abstract Full Text Full Text PDF PubMed Scopus (16) Google Scholar The important information provided by Sun et al.1Sun K. Cedarbaum E. Hill C. et al.Association of right ventricular dilation on echocardiogram with in-hospital mortality among patients Hospitalized with COVID-19 compared with bacterial pneumonia.J Am Soc Echocardiogr. 2023; 36: 558-562Abstract Full Text Full Text PDF Scopus (1) Google Scholar relates to the fact that RV dilation, which precedes RV dysfunction, allows early detection of patients with an increased mortality risk already before the occurrence of relevant RV dysfunction. However, the statement that “RV dysfunction is not associated with mortality in patients with COVID-19 pneumonia” could be misleading because it may suggest that only RV dilation, but not RV dysfunction, is a mortality risk factor for patients with severe COVID-19. A recent comparison of pneumonias due to SARS-CoV-2 and influenza revealed much worse outcomes in COVID-19 patients and, specific for SARS-CoV-2 pneumonia was the frequent gradual worsening after day 7.5Lyons P.G. Bhavani S.V. Mody A. et al.Hospital trajectories and early predictors of clinical outcomes differ between SARS-CoV-2 and influenza pneumonia.EBioMedicine. 2022; 85: 104295Abstract Full Text Full Text PDF PubMed Scopus (3) Google Scholar However, although SARS-CoV-2 pneumonia was characterized by greater radiological abnormalities, baseline radiography did not correlate with the clinical outcome.5Lyons P.G. Bhavani S.V. Mody A. et al.Hospital trajectories and early predictors of clinical outcomes differ between SARS-CoV-2 and influenza pneumonia.EBioMedicine. 2022; 85: 104295Abstract Full Text Full Text PDF PubMed Scopus (3) Google Scholar The latter could explain both the lack of association between the RV function at admission to the hospital and patient outcome reported by Sun et al.1Sun K. Cedarbaum E. Hill C. et al.Association of right ventricular dilation on echocardiogram with in-hospital mortality among patients Hospitalized with COVID-19 compared with bacterial pneumonia.J Am Soc Echocardiogr. 2023; 36: 558-562Abstract Full Text Full Text PDF Scopus (1) Google Scholar and the discordance between that finding and several other studies, which found a close association between RV dysfunction and mortality risk for patients with severe SARS-CoV-2 pneumonia. Unfortunately, in Table 1, the data regarding RV volume are misleading as the volume is described as normal or showing varying degrees of reduction and also as normal or dilated. Independently of the above remarks, the evidence provided by Sun et al.1Sun K. Cedarbaum E. Hill C. et al.Association of right ventricular dilation on echocardiogram with in-hospital mortality among patients Hospitalized with COVID-19 compared with bacterial pneumonia.J Am Soc Echocardiogr. 2023; 36: 558-562Abstract Full Text Full Text PDF Scopus (1) Google Scholar regarding the possible early detection of SARS-CoV-2-infected patients at risk for life-threatening afterload mismatch-induced RV failure by TTE (even before the emergence of relevant RV dysfunction) underlines the importance of echocardiography for in-hospital monitoring of these patients.

Coronavirus disease 2019 (COVID-19) is associated with particularly frequent acute respiratory distress syndrome (ARDS), which is also associated with higher mortality. The poorer prognosis of COVID-19 ARDS is due mainly to widespread endothelial damage that promotes thrombogenesis and impairs vasoregulation in small pulmonary vessels, resulting in severe ventilation-perfusion mismatch.1Dandel M. Pathophysiology of COVID-19–associated acute respiratory distress syndrome.Lancet Respir Med. 2021; 9: e4Abstract Full Text Full Text PDF PubMed Scopus (17) Google Scholar Because the mortality rate with severe COVID-19 ARDS can reach 85% without the use of extracorporeal membrane oxygenation (ECMO),2Zhou F. Yu T. Du R. et al.Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study.Lancet. 2020; 395: 1054-1062Abstract Full Text Full Text PDF PubMed Scopus (17387) Google Scholar the excellent 1-year outcomes with venovenous (VV) ECMO reported by Smith and colleagues3Smith D.E. Chang H.S. Geraci T.C. et al.One-year outcomes with venovenous extracorporeal membrane oxygenation support for severe COVID-19..Ann Thorac Surg. 2022; 114: 70-75Abstract Full Text Full Text PDF PubMed Scopus (10) Google Scholar are promising. Evaluating exclusively patients supported by VV-ECMO, Smith and colleagues3Smith D.E. Chang H.S. Geraci T.C. et al.One-year outcomes with venovenous extracorporeal membrane oxygenation support for severe COVID-19..Ann Thorac Surg. 2022; 114: 70-75Abstract Full Text Full Text PDF PubMed Scopus (10) Google Scholar proved convincingly the feasibility and lifesaving value of VV-ECMO in appropriately selected patients with COVID-19 ARDS. The particularly good results of the study clearly speak against the initial hesitation toward the use of ECMO in the management of COVID-19 ARDS. The question still remains about the previously published discrepancies in the usefulness of VV-ECMO, which were discouraging because the survival outcomes were often lower than those expected for non-COVID ARDS. A possible explanation for those discrepancies could be differences in the prevalence of acute cardiorespiratory failure necessitating both extracorporeal gas exchange and temporary mechanical circulatory support. In 1 study, venoarterial or other ECMO configurations were necessary in 138 (9%) of the ECMO-supported patients with COVID-19 ARDS.4Lorusso R. Combes A. Lo Coco V. et al.ECMO for COVID-19 patients in Europe and Israel.Intensive Care Med. 2021; 47: 344-348Crossref PubMed Scopus (74) Google Scholar Thus, the existence of COVID-19 ARDS associated with acute cardiorespiratory failure, necessitating both respiratory and circulatory support, must also be considered. As proved by Smith and coworkers, selection of patients for VV-ECMO is reliably practicable. However, data about the selection of patients with severe COVID-19 ARDS who may necessitate another type of ECMO support are insufficient. Given the high incidence of diffuse pulmonary thrombotic microangiopathy with consequent afterload mismatch-induced right ventricular (RV) failure, careful echocardiographic monitoring of the right-sided heart for timely detection of RV pressure overloading becomes indispensable in patients with COVID-19 ARDS.1Dandel M. Pathophysiology of COVID-19–associated acute respiratory distress syndrome.Lancet Respir Med. 2021; 9: e4Abstract Full Text Full Text PDF PubMed Scopus (17) Google Scholar Echocardiography can help in optimizing the selection of ECMO candidates and decision-making about the most appropriate mechanical support strategy (VV-ECMO, venoarterial ECMO, or VV-ECMO plus RV or left ventricle temporary percutaneous mechanical support). One-Year Outcomes With Venovenous Extracorporeal Membrane Oxygenation Support for Severe COVID-19The Annals of Thoracic SurgeryVol. 114Issue 1PreviewSevere coronavirus disease 2019 (COVID-19) can cause acute respiratory failure requiring mechanical ventilation. Venovenous (VV) extracorporeal membrane oxygenation (ECMO) has been used in patients in whom conventional mechanical ventilatory support has failed. To date, published data have focused on survival from ECMO and survival to discharge. In addition to survival to discharge, this study reports 1-year follow-up data for patients who were successfully discharged from the hospital. Full-Text PDF Improving Outcomes for Patients With Severe COVID-19 Acute Respiratory Distress Syndrome Supported With Extracorporeal Membrane OxygenationThe Annals of Thoracic SurgeryVol. 115Issue 4PreviewWe appreciate the thoughtful Letter to the Editor by Dr Dandel1 regarding our publication, “One-Year Outcomes With Venovenous Extracorporeal Membrane Oxygenation Support for Severe COVID-19.”2 We believe these comments highlight two important issues regarding the use of extracorporeal membrane oxygenation in patients with coronavirus disease 2019 (COVID-19). Full-Text PDF

This commentary refers to 'Factors influencing post-surgical survival in degenerative mitral regurgitation', by S.C. Butcher et al., https://doi.org/10.1093/eurheartj/ehad004 and the discussion piece `Rescue surgery for degenerative mitral regurgitation should be recognized for what it is: indispensable but imperfect', by S.C. Butcher et al., https://doi.org/10.1093/ eurheartj/ehad242.

Given that in the presence of mitral regurgitation (MR), the difference between the left ventricular (LV) end-diastolic and end-systolic volume is no longer the forward stroke volume (SVf) but becomes the sum of SVf and regurgitant volume, it is evident that MR can increase the volumetrically measured ejection fraction (EF) correspondingly with the increased blood volume leaving the LV during the systole. 1 Dandel M Hetzer R. Ventricular systolic dysfunction with and without altered myocardial contractility: clinical value of echocardiography for diagnosis and therapeutic decision-making. Int J Cardiol. 2021; 327: 236-250 Abstract Full Text Full Text PDF PubMed Scopus (8) Google Scholar , 2 Maréchaux S Terrade J Biausque F Lefetz Y Deturck R Asseman P Le Jemtel TH Ennezat PV Exercise-induced functional mitral regurgitation in heart failure and preserved ejection fraction: a new entity. Eur J Echocardiogr. 2010; 11: E14 Crossref PubMed Scopus (20) Google Scholar , 3 Hetzer R Dandel M. Early detection of left ventricular dysfunction in patients with mitral regurgitation due to flail leaflet is still a challenge. Eur Heart J. 2011; 32: 665-667 Crossref PubMed Scopus (17) Google Scholar With aggravation of MR, the regurgitant fraction increases to the detriment of SVf without reduction of the LVEF, even with further reduction of the SVf. 1 Dandel M Hetzer R. Ventricular systolic dysfunction with and without altered myocardial contractility: clinical value of echocardiography for diagnosis and therapeutic decision-making. Int J Cardiol. 2021; 327: 236-250 Abstract Full Text Full Text PDF PubMed Scopus (8) Google Scholar ,3 Hetzer R Dandel M. Early detection of left ventricular dysfunction in patients with mitral regurgitation due to flail leaflet is still a challenge. Eur Heart J. 2011; 32: 665-667 Crossref PubMed Scopus (17) Google Scholar This leads to an overestimation of the EF and thereby also of the LV contractile function in both heart failure with reduced LVEF and heart failure with preserved LVEF (HFpEF). 2 Maréchaux S Terrade J Biausque F Lefetz Y Deturck R Asseman P Le Jemtel TH Ennezat PV Exercise-induced functional mitral regurgitation in heart failure and preserved ejection fraction: a new entity. Eur J Echocardiogr. 2010; 11: E14 Crossref PubMed Scopus (20) Google Scholar Nevertheless, the impact of MR on the course of HFpEF still receives little attention. At least in part, this might be due to the increasing overestimation of the LVEF with the progression of MR. In view of these aspects, the recent study by Jiang et al 4 Jiang GY Xu J Manning WJ Markson LJ Khabbaz KR Garan AR Sabe MA Strom JB. Mitral regurgitation and mortality risk in Medicare beneficiaries with heart failure and preserved ejection fraction. Am J Cardiol. 2022; 183: 40-47 Abstract Full Text Full Text PDF PubMed Scopus (1) Google Scholar is of particular importance. It proves that moderate-to-severe and severe secondary MR in patients with HFpEF is associated with an increased risk of all-cause mortality, which is in line with the expected consequences of a serious mitral incompetence for the whole cardiovascular system. In that study, the deleterious effects of MR on the heart and pulmonary circulation in HFpEF are also notably reflected by the left atrial volume, the peak tricuspid regurgitation velocity, and the prevalence of relevant tricuspid regurgitation, which were significantly higher in patients with advanced MR. 4 Jiang GY Xu J Manning WJ Markson LJ Khabbaz KR Garan AR Sabe MA Strom JB. Mitral regurgitation and mortality risk in Medicare beneficiaries with heart failure and preserved ejection fraction. Am J Cardiol. 2022; 183: 40-47 Abstract Full Text Full Text PDF PubMed Scopus (1) Google Scholar

Long-term mechanical circulatory support by a left ventricular assist device (LVAD), with or without an additional temporary or long-term right ventricular (RV) support, is a life-saving therapy for advanced heart failure (HF) refractory to pharmacological treatment, as well as for both device and surgical optimization therapies. In patients with chronic non-ischemic cardiomyopathy (NICM), timely prediction of HF’s transition into its end stage, necessitating life-saving heart transplantation or long-term VAD support (as a bridge-to-transplantation or destination therapy), remains particularly challenging, given the wide range of possible etiologies, pathophysiological features, and clinical presentations of NICM. Decision-making between the necessity of an LVAD or a biventricular assist device (BVAD) is crucial because both unnecessary use of a BVAD and irreversible right ventricular (RV) failure after LVAD implantation can seriously impair patient outcomes. The pre-operative or, at the latest, intraoperative prediction of RV function after LVAD implantation is reliably possible, but necessitates integrative evaluations of many different echocardiographic, hemodynamic, clinical, and laboratory parameters. VADs create favorable conditions for the reversal of structural and functional cardiac alterations not only in acute forms of HF, but also in chronic HF. Although full cardiac recovery is rather unusual in VAD recipients with pre-implant chronic HF, the search for myocardial reverse remodelling and functional improvement is worthwhile because, for sufficiently recovered patients, weaning from VADs has proved to be feasible and capable of providing survival benefits and better quality of life even if recovery remains incomplete. This review article aimed to provide an updated theoretical and practical background for those engaged in this highly demanding and still current topic due to the continuous technical progress in the optimization of long-term VADs, as well as due to the new challenges which have emerged in conjunction with the proof of a possible myocardial recovery during long-term ventricular support up to levels which allow successful device explantation.

To the Editor: I read with interest the study by Beyls et al.1 which compared the different clinical characteristics and outcomes of patients with COVID-19–related respiratory distress syndrome (CARDS) requiring veno-venous extracorporeal membrane oxygenation (VV-ECMO) during the three epidemic waves of COVID-19 in France. Despite the increasing knowledge on the particularities of severe COVID-19 and the growing experience in the management of severe CARDS, that study revealed a massive increase in the 90 day mortality of patients undergoing VV-ECMO during the second epidemic wave. One plausible explanation for that important observation could be the fact that over the course of the pandemic, new variants of the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) have continuously emerged. Because the different waves of infection were mainly associated with one or more SARS-CoV-2 "variants of concern" (VOC) with different pathogenicity, it appears obvious that the pathogenicity of the dominant VOC in an infection wave can have important impacts on the outcomes of patients with severe COVID-19. Indeed, the Delta/B.1.617.2 variant, which was dominant during the second wave, is known to be associated with higher risk of death than both the previously dominant VOCs (i.e., Alpha/B.1.1.7, Beta/B.1.351 and Gamma/P.1) and the Omicron/B1.1.529 variant which became the dominant VOC during third wave.2,3 The excessively high mortality rate (i.e., 85.7%1) of patients supported by ECMO during the second wave deserves particular attention because a renewed appearance of more pathogenic VOCs cannot be ruled out. The high incidence of extensive pulmonary thrombotic microangiopathy associated with severe ventilation-perfusion mismatch, increased resistance in the pulmonary circulation and frequent afterload-induced right ventricular (RV) failure, which were identified as distinct features of severe CARDS (especially in infections caused by the Delta/B.1.617.2 variant) were often the leading cause of death attributed to COVID-19.4,5 Early detection of patients with increasing RV hemodynamic overloading can facilitate the selection of the most appropriate management (including the requirement of ECMO or a combined respiratory and circulatory support), which can be decisive for the patients' survival.4 In severe RV afterload mismatch, the RV output decreases substantially, and RV dilation-related tricuspid regurgitation can rapidly increase. In such situations, attempting to treat the underlying etiology of impaired gas exchange using VV-ECMO alone may become insufficient.4 Considering the high incidence and the deleterious prognostic impact of right heart involvement in severe COVID-19 it seems likely that this was also the major cause of the high mortality rate documented by Beyls et al.1 for their ECMO-supported patients (92% with VV-ECMO) during the second wave. Thus, close monitoring of the right heart in patients with CARDS associated with hemodynamic instability, already before overt RV failure develops, could substantially improve therapeutic decision-making. It is therefore difficult to understand the still limited use of routine echocardiography for the surveillance of hospitalized patients with COVID-19. Echocardiography can improve the identification of patients with CARDS requiring ECMO therapy, the selection of the most appropriate support strategy (VV-ECMO, veno-arterial-ECMO, or VV-ECMO plus RV or left ventricle temporary percutaneous mechanical support) and also the weaning decision-making after cardiopulmonary amelioration during the support.

ObjectivesParameters of left ventricular (LV) mechanics, obtained from speckle-tracking echocardiography (STE), were found to be of prognostic value in patients with heart failure and those who underwent cardiac surgery. This study aimed to assess the value of STE in patients scheduled to undergo surgical ventricular restoration (SVR).MethodsA total of 158 consecutive patients with baseline STE who underwent SVR due to an LV anteroapical aneurysm were included in the analysis. Preoperative longitudinal STE parameters were evaluated for their association with an outcome, defined as all-cause mortality, LV assist device implantation, or heart transplantation. The echocardiographic follow-up to assess the change in the regional function of the segments remote from the aneurysm was performed in 43 patients at a median of 10 months [interquartile range (IQR): 6–12.7 months] after SVR.ResultsDuring a median follow-up of 5.1 years (IQR: 1.6–8.7 years), events occurred in 68 patients (48%). Less impaired mean basal end-systolic longitudinal strain (BLS) with a cutoff value ≤ −10.1 % demonstrated a strong association with event-free survival, also in patients with an LV shape corresponding to an intermediate shape between aneurysmal and globally akinetic. Initially hypo- or akinetic basal segments with preoperative end-systolic strain ≤ −7.8% showed a greater improvement in wall motion at the short-term follow up.ConclusionPatients with less impaired preoperative BLS exhibited a better event-free survival after SVR, also those with severe LV remodeling. The preserved preoperative segmental longitudinal strain was associated with a greater improvement in regional wall motion after SVR. BLS assessment may play a predictive role in patients with an LV anteroapical aneurysm who are scheduled to undergo SVR.

To the Editor: I read with great interest the study by Chotalia et al (1) published in a recent issue of Critical Care Medicine, which provides further important data concerning the still insufficiently considered impact of coronavirus disease 2019 (COVID-19)–related right ventricular (RV) dysfunction on the therapeutic approaches to COVID-19 and patient survival. The high occurrence rate of extensive pulmonary thrombotic microangiopathy associated with more severe hypoxemic respiratory failure, increased resistance in the pulmonary circulation, and frequent afterload mismatch-induced RV failure is a distinctive feature of COVID-19–related acute respiratory distress syndrome (CARDS) and also a main cause for the particularly high mortality related with severe infections (2). Early detection of hospitalized patients with evidence of increasing RV hemodynamic overloading can facilitate the selection of the most appropriate management (e.g., RV protective ventilation, anticoagulation, pulmonary vasodilation, extracorporeal membrane oxygenation, etc.), which can be decisive for their survival. Chotalia et al (1) demonstrated that even simple parameters measurable by conventional transthoracic echocardiography (TTE) can be useful for detection of RV dilation and systolic dysfunction. The authors also found that the RV phenotype characterized by cavity dilation (RV/left ventricular end-diastolic area ratio > 0.6) and systolic impairment (RV fractional area change [RVFAC] < 0.35%) was independently associated with mortality (1). Unfortunately, Chotalia et al (1) did not include the prevalence and severity of tricuspid regurgitation (TR) in their study. This would have been important because greater than or equal to moderate TR was already found associated with increased odds for 30-day mortality in hospitalized patients with COVID-19 (3). Assessment of TR severity is also important because TR can induce misleading RVFAC and tricuspid annular peak systolic excursion (TAPSE) changes. By facilitating the RV free wall transversal and longitudinal motion, which will increase RVFAC and TAPSE (correspondingly to the increased blood volume leaving the RV in systole), TR can lead to an overestimation of RV systolic function (2). The distinctively severe ventilation-perfusion mismatch with life-threatening hypoxemia resulting from pulmonary endothelial damage that promotes small vessel thrombosis and impairs the pulmonary vasoregulation can become the key problem already in early CARDS stages (4). Elevated pulmonary arterial systolic pressure appeared detectable by echocardiography in up to 70% of hospitalized COVID-19 patients and the prevalence of pulmonary hypertension in ventilated patients with CARDS was found four times higher compared with COVID-19 patients without the need for mechanical ventilation (2,5). RV dilation was also detectable in about 30–70% of the hospitalized patients with COVID-19, and assessment of RV pulmonary artery coupling by echocardiography revealed a significant uncoupling in up to 50% of the patients necessitating intensive care (4). Additional monitoring of changes in the pulmonary circulation could be therefore particularly helpful in hospitalized patients with COVID-19. Nevertheless, TTE is generally still underused in monitoring of hospitalized COVID-19 patients and, if it is used, the importance of the right-sided heart involvement is often underestimated. Hospitals where 65% of the patients with COVID-19 receive TTE that focuses on both ventricles like that in Birmingham (1) are still rather rare. Full implementation of bedside TTE focused on the right-sided heart, which is currently still underused, could facilitate more personalized management and treatment of hospitalized patients and can contribute toward reducing the high mortality associated with severe acute respiratory syndrome coronavirus 2 infection.