Left Ventricular Distension Research Articles

Abstract 4136694: Impact of left ventricular support devices on myocardial and pulmonary recovery in patients with cardiogenic shock treated with venoarterial extracorporeal membrane oxygenation

Background: Venoarterial-extracorporeal membrane oxygenation (VA-ECMO) is used to treat cardiogenic shock. However, retrograde arterial perfusion from the femoral artery can increase left ventricular (LV) afterload, resulting in LV distention which may hamper myocardial recovery and worsen pulmonary congestion. An intra-aortic balloon pump (IABP) can mitigate LV afterload, and Impella (Abiomed, Danvers, MA) can directly unload LV pressure. This study aimed to evaluate the efficacy of LV support devices during VA-ECMO in patients with cardiogenic shock. Methods: We retrospectively collected data from 213 consecutive patients treated with VA-ECMO due to cariogenic shock at our institution between January 2013 and December 2023. Patients were categorized as either receiving VA-ECMO alone or VA-ECMO with an LV support device. The LV support device was characterized as VA-ECMO with IABP or Impella. Data were analyzed for mortality, weaning from VA-ECMO, and changes in pulmonary congestion using the congestion score index (CSI), which is a semi-quantitative approach to pulmonary congestion based on a 6-zone evaluation of chest radiography, scoring each zone from 0 (no congestion) to 3 (intense pulmonary edema). Results: In this study, 95 patients received VA-ECMO alone, whereas 118 patients received an LV support device (101 VA-ECMO with IABP and 17 VA-ECMO with Impella). LV support devices improved weaning from VA-ECMO (odds ratio, 3.09 [95% confidence interval (CI), 1.75–5.55]; p<0.0001) whereas there was no difference in IABP versus Impella cohorts. Compared with VA-ECMO alone, patients with VA-ECMO with an LV support device had better survival at 30 days (OR, 3.04 [95% CI, 1.73–5.43]; p<0.0001). The rate of survival to discharge was better in VA-ECMO with an LV support device versus VA-ECMO alone (hazard ratio, 2.51 [95% CI, 1.72–3.65]; p<0.0001). The evaluation of pulmonary congestion using the CSI revealed that congestion significantly improved in VA-ECMO with Impella (changes of CSI: 1.86 to 1.36) but not in VA-ECMO with IABP (1.80 to 1.96) and VA-ECMO alone (1.94 to 2.14). Conclusion: An LV support device may be associated with reduced mortality and increased success in weaning off VA-ECMO in patients with cardiogenic shock. Impella may be particularly effective in reducing pulmonary congestion.

LA reservoir strain predicts elevated left atrial pressure in patients with Veno-Arterial (VA) extracorporeal membrane oxygenator (ECMO) support for cardiogenic shock

Abstract Background Veno-arterial (VA) extracorporeal membrane oxygenator (ECMO) is not a left ventricular (LV) support system as it increases aortic pressure and LV afterload due to retrograde blood flow in the aorta. This can lead to complications such as increased LV volume (LV distention), increased LV and left atrial (LA) pressures, and pulmonary edema. We sought to investigate the correlation between LA strain and invasive LA pressure (LAP) in patients with ECMO support for cardiogenic shock undergoing atrial septostomy with stenting. Methods and Results A total of 24 consecutive patients (52±20 years; 83% were male) undergoing atrial septostomy with stenting while being on ECMO support for cardiogenic shock for left heart decompression were analyzed. LAP was measured immediately after transeptal puncture and before deployment of interatrial septal stent. A comprehensive echocardiogram was performed in all patients prior to atrial septostomy. Median time difference between echocardiogram and LAP measurement was 3.5 (0.5-20) hours. LA strain analysis was performed using the TomTec Arena 2D-cardiac performance analysis (CPA) software. LA reservoir strain was measured at peak systole during the reservoir phase in a single apical 4-chamber view. Intraclass correlation coefficients between 2 different investigators were excellent (All> 0.95). Median LA reservoir strain and LAP were 3.2 (0.5-1) % and 23 (8-53) mmHg, respectively. LA reservoir strain significantly correlated with LAP (r=0.53, p=0.034). LA reservoir strain of < 1.5% can effectively predict markedly elevated LAP (LA> 30 mmHg) (OR =9.9, p =0.0016). Conclusions LA reservoir strain significantly correlated with invasive LAP. With the advent of strain imaging software, LA reservoir strain is a feasible, reproducible, noninvasive, and straightforward method to predict the need for left heart decompression and/or to guide optimal afterload management in patients with VA-ECMO for cardiogenic shock. Further a prospective simultaneous echocardiographic and invasive LAP study is needed.

An analytic method to investigate hemodynamics of the cardiovascular system: Biventricular system.

Previously, we found analytic solutions for single ventricular system based on the lumped parameter model (LPM). In this study, we generalized the method to biventricular system and derived its analytic solutions. LPM is just a set of differential equations, but it is difficult to solve due to time-varying ventricular elastance and high order. Mathematically, there exist no elementary solutions for time-varying equations. It turns out that instead of differential equations, according to volume conservation, a set of algebraic equations can be carried out. The solutions of the set of equations are just physiological states at end of systolic and diastolic phases such as end systolic/diastolic pressure/volume of left ventricle. As a preliminary application, the method is utilized to deduce the hemodynamic effects of VA ECMO. Left ventricular (LV) distension, a serious complication of VA ECMO, is usually attributed to factors such as increased afterload, inadequate LV unloading, reduced myocardial contractility or aortic valve regurgitation (AR), bronchial and Thebesian return in the absence of aortic valve (AoV) opening. Among these, reduced contractility and AR are strongly associated with LV distension. However, in the absence of reduced contractility or AR, it is less clear whether increased afterload or inadequate LV unloading alone can cause LV distension. This leads to the critical question: under what conditions does LV distension occur in the absence of reduced contractility or AR? The analytic formulas derived in this study give conditions for LV distension. Furthermore, the results show that the analytic hemodynamics are coincident with simulated results.

Combined use of VA-ECMO and Impella (ECPELLA) improves short- and long-term mortality in patients with cardiogenic shock who received VA-ECMO

Abstract Introduction Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is beneficial for patients with refractory cardiac arrest and cardiogenic shock. Despite its benefits, VA-ECMO increases left ventricular (LV) afterload and causes pulmonary edema and LV distension. Recently, a transcatheter left ventricular assist device, Impella has been introduced and potential benefits of the concomitant use of VA-ECMO and Impella (ECPELLA) are expected. However, with the concomitant increase in complications, the utility of ECPELLA remains controversial and unsettled. Objective This single-site cohort study aimed to assess the impact of ECPELLA compared to VA-ECMO with or without intra-aortic balloon pump (IABP) in patients with refractory cardiogenic shock, including cardiac arrest, who received VA-ECMO treatment. Methods We retrospectively reviewed 245 consecutive patients, who underwent VA-ECMO treatment between January 2012 and December 2021 at our institute. Seventeen patients for difficult weaning from cardiopulmonary bypass (n = 15) and as a backup during high-risk transcatheter aortic valve implantation (n = 2) were excluded. The patients were divided into two groups, ECEPLLA (n = 64) and VA-ECMO with or without IABP (n = 164). We performed propensity score analysis with 1:1 score matching using dependent variables of age, the rate of male gender, acute coronary syndrome, out-of-hospital and in-hospital cardiac arrest, and extracorporeal cardiopulmonary resuscitation. We evaluated hemodynamic data, safety profiles, and mortality. Results Following matching, 58 ECPELLA and 58 VA-ECMO patients were included for analysis. No significant differences in the adjusted factors and comorbidities were found between the two groups, except for a significantly higher prevalence of chronic kidney disease in the VA-ECMO group compared to the ECPELLA group. Seventy-one percent of patients received concomitant use of IABP in the VA-ECMO group. During the first 72 hours following the initiation of VA-ECMO, the ECPELLA group received a significantly higher total mechanical circulatory support flow and correspondingly less administration of catecholamines compared with the VA-ECMO group. There were no statistical differences in safety profiles, except for hemolysis and embolic cerebral infarction, between the treatment groups. Kaplan-Meier analysis demonstrated that the 30-day and 1-year survival rates were significantly higher in the ECPELLA group than in the VA-ECMO group. Multivariate cox proportional hazard analysis revealed that age (hazard ratio [HR], 1.36 [10 years increase]; 95% confidence interval [CI], 1.15–1.62, p < 0.001), lactate level at ER (HR 1.07; 95% CI 1.03–1.12, p = 0.001), and ECPELLA (HR, 0.47, 95% CI, 0.30–0.73, p = 0.008) were significantly associated with the 1-year mortality. Conclusion ECPELLA was associated with improvement of short- and long-term mortality in patients with refractory cardiogenic shock who received VA-ECMO.Total MCS flow index and VISKaplan-Meier for 1-year mortality

Abstract 18693: Effect of Mechanical Unloading on Cardiogenic Shock Severity in Venoarterial Extracorporeal Membrane Oxygenation Patients

Introduction: Mechanical unloading (MU) with Intra-aortic balloon pump (IABP) or Impella is commonly used to prevent left ventricular (LV) distension in VA-ECMO patients, but its impact on shock severity is not well described. Methods: Patients treated with VA-ECMO in our hospital between 2016-2022 for cardiogenic shock (CS) due to LV failure not related to cardiac surgery were included if no MU was used or it was instituted within 24h of ECMO cannulation. Patients were grouped according to MU: ECMO alone, ECMO + IABP or ECMO + Impella. Linear mixed effects models adjusting for age, sex, hypertension, acute myocardial infarction (AMI) etiology of shock and pre-ECMO cardiac arrest (CA) were used to assess the impact of MU on hemodynamic and perfusion markers. R version 4 was used for analysis. Results: Among 68 patients included, 18 received ECMO alone, 17 ECMO + IABP, and 33 ECMO + Impella. Age and CA were similar across groups. The Impella group had a higher proportion of men and patients with AMI. Pulmonary artery diastolic pressure was unchanged in all groups. Compared to ECMO alone, MU did not enhance lactate clearance (interaction: IABP p=0.7, Impella p=0.22), but it did improve the vasopressor-inotropic score (IABP p=0.03, Impella p=0.01), serum creatinine (IABP p=0.03, Impella p=0.04), and alanine transaminase (IABP only p=0.02). Survival to decannulation was similar in patients with ECMO alone (50%), Impella (64%) and IABP (65%) (p=0.68). Conclusions: In adults treated with VA-ECMO for CS unrelated to cardiac surgery, LV MU can lead to improvements in CS severity.

Left ventricular decompression in veno-arterial extracorporeal membrane oxygenation

Objective: Our study investigates the frequency and determines the characteristics and outcomes of patients with venoarterial extracorporeal membrane oxygenation (VA-ECMO) support requiring left ventricular unloading at Ha Noi Heart hospital.
 Methods: A cross-sectional descriptive study was conducted among 84 patients undergoing VA- ECMO between December 2018 and December 2021 at Ha Noi Heart hospital. Signs of left ventricular distension in VA-ECMO (Inadequate arterial blood pressure pulsatility, “smoke like” effect in left ventricular, reduced aortic valve opening/absent aortic valve closure, pulmonary edema, left ventricular distension) were studied before and at 24 hours, 48 hours and 72 hours after VA-ECMO support.
 Results: Left ventricular distention requiring decompression occurs in 44,1% of patients supported with VA-ECMO 3.6% (left ventricular distension), inadequate arterial blood pressure pulsatility (77,4%), “smoke like” effect in left ventricular (53,6%), pulmonary edema 47 ,6%; reduced aortic valve opening/absent aortic valve closure in 35,7% of the cases. Left ventricular decompression may improve clinical outcomes from 48 hours onwards (p<0.05). There were no differences in age, left ventricular ejection fraction before VA-ECMO, ECRP rates, continuous renal replacement therapy rates, duration of mechanical ventilation, duration of ECMO, hospital length of stay and diagnosis of patients with and without left ventricular unloading (p>0.05). The proportion of patients using invasive left ventricular decompression who successful weaning from VA- ECMO was significantly higher than in the group without left ventricular unloading (94,5% versus 74,4%; p<0.05).The survival rate of patients using left ventricular unloading tended to be higher than that in the group without left ventricular decompression (72,9% vs 53,2%; p>0.05) ). Complications of invasive left ventricular decompression included 1 patient with occlusion of the junction requires removal of the left atrial drainage.
 Conclusion: Left heart decompression may contribute to increasing the success rate of VA-ECMO weaning and may help to improve the survival rate of patients with VA ECMO.

The impact of aortic valve regurgitation on the combination therapy of VA-ECMO and Imeplla support in severe cardiogenic shock: a simulation study

Background: The utilization of a combination of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) and Impella, ECPELLA, has become widespread among patients with cardiogenic shock. The utilization of VA-ECMO in the presence of aortic regurgitation (AR) can result in significant left ventricular (LV) distention. Additionally, the implantation of Impella via the aortic valve frequently induces AR clinically. We established a simulation model and evaluated the impact of AR on hemodynamics under ECPELLA. Furthermore, assuming that the reverse flow of AR is strongly determined by aortic pressure (AP) level, we simulated a scenario where AP was further decreased. Methods: We employed Simulink® (Mathworks, Inc.). The systemic and pulmonary circulations were modeled using a 5-element resistance-capacitance network. Four cardiac chambers were represented by time-varying elastance. We compared the aortic regurgitant flow (Far), total systemic flow (Ftotal), and LV pressure-volume relationship under various severities of AR and varying Impella (0-3.7 L/min) and VA-ECMO (0-5 L/min) flows. AR grades were adjusted by the regurgitant resistance and classified as mild, moderate, and severe, mimicking a clinical scenario. Results: Without AR, ECMO significantly increased Ftotal and raised LV end-diastolic pressure (LVEDP). Impella increased Ftotal and decreased LVEDP. The concomitant presence of AR exacerbated the increase of LVEDP by ECMO and the reduction of LVEDP by Impella. Under ECPELLA support (VA-ECMO: 3 L/min) with mild AR, the increase of Impella support (1 to 3.5 L) increased Ftotal and Far, while decreasing LVEDP, indicating the prevention of AR-induced LV distention. Additionally, the presence of mild AR prevented the Impella-induced left ventricular suction that is commonly observed under ECPELLA support with high-flow VA-ECMO. In the case of moderate AR, while the hemodynamic trends were similar to those observed under mild AR, Impella was unable to prevent the increment of LVEDP to a critical level (< 20 mmHg). However, by decreasing AP through reducing resistance (e.g. vasodilators), both Far and LVEDP were dramatically reduced and Ftotal was increased under ECPELLA support. Conclusion: The concomitant presence of AR in ECPELLA condition increased LV load, while prevented LV suction. The use of vasodilator in ECPELLA with AR could attenuate AR, increase systemic perfusion, and reduce LV load. The optimal control of Impella and VA-ECMO flows and AP can maximize the hemodynamic and LV unloading impacts of ECPELLA. no funding This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Pulmonary Protection from Left Ventricular Distension During Venoarterial Extracorporeal Membrane Oxygenation: Review and Management Algorithm.

The use of venoarterial extracorporeal membrane oxygenation (VA-ECMO) in adults for refractory cardiogenic shock has risen exponentially during the prior decade. Although VA-ECMO provides cardiopulmonary support, it can alter left ventricular (LV) loading conditions leading to LV distension, which makes the lungs susceptible to congestion and promotes intracardiac thrombosis. These conditions can be alleviated by pharmacologic and mechanical unloading, but gaps in knowledge remain on optimal timing and methods of this approach. This review provides an overview of the epidemiology of VA-ECMO, describes pathophysiology and methods for monitoring and reducing LV loading and summarizes contemporary studies examining the association between LV unloading and adverse events. We offer a simple protocol for implementing LV unloading during VA-ECMO to provide pulmonary protection and improve outcomes.

Alterations in Coronary Blood Flow and the Risk of Left Ventricular Distension in Venoarterial Extracorporeal Membrane Oxygenation.

Previous theoretical studies have suggested that veno-arterial extracorporeal membrane oxygenation (VA-ECMO) ought to consistently result in markedly increased left ventricular (LV) intracavitary pressures and volumes because of increased LV afterload. However, this phenomenon of LV distension does not universally occur and occurs only in a minority of cases. We sought to explain this discrepancy by considering the potential implications of VA-ECMO support on coronary blood flow and consequently improved LV contractility (the "Gregg" effect), in addition to the effects of VA-ECMO support upon LV loading conditions, in a lumped parameter-based theoretical circulatory model. We found that LV systolic dysfunction resulted in reduced coronary blood flow; VA-ECMO support augmented coronary blood flow proportionally to the circuit flow rate. On VA-ECMO support, a weak or absent Gregg effect resulted in increased LV end-diastolic pressures and volumes and increased end-systolic volume with decreased LV ejection fraction (LVEF), consistent with LV distension. In contrast, a more robust Gregg effect resulted in unaffected and/or even reduced LV end-diastolic pressure and volume, end-systolic volume, and unaffected or even increased LVEF. Left ventricular contractility augmentation proportional to coronary blood flow increased by VA-ECMO support may be an important contributory mechanism underlying why LV distension is observed only in a minority of cases.

Left Ventricular Unloading in Patients on Venoarterial Extracorporeal Membrane Oxygenation Therapy in Cardiogenic Shock: Prophylactic Versus Bail-Out Strategy

The benefit of prophylactic left ventricular (LV) unloading during venoarterial extracorporeal membrane oxygenation (VA-ECMO) in selected patients at risk of developing LV distension remains unclear. We enrolled 136 patients treated with Impella pump decompression during VA-ECMO therapy for refractory cardiogenic shock. Patients were stratified by specific indication for LV unloading in the prophylactic vs. bail-out group. The bail-out unloading strategy was utilized to treat LV distension in VA-ECMO afterload-associated complications. The primary endpoint was all-cause 30-day mortality after VA-ECMO implantation. The secondary endpoint was successful myocardial recovery, transition to durable mechanical circulatory support (MCS), or heart transplantation. After propensity score matching, prophylactic unloading was associated with a significantly lower 30-day mortality risk (risk ratio 0.38, 95% confidence interval 0.23-0.62, and p < 0.001) and a higher probability of myocardial recovery (risk ratio 2.9, 95% confidence interval 1.48-4.54, and p = 0.001) compared with the bail-out strategy. Heart transplantation or durable MCS did not differ significantly between groups. Prophylactic unloading compared with the bail-out strategy may improve clinical outcomes in selected patients on VA-ECMO. Nevertheless, randomized trials are needed to validate these results.

Proportional pulmonary pulse pressure: A new index to assess response to veno-arterial extracorporeal membrane oxygenation.

Based on theoretical physiology, the ratio of pulmonary artery pulse pressure to mean pulmonary pressure (PP-MPAP), termed proportional pulmonary pulse pressure, provides a measure of coupling between the right ventricle and the pulmonary circulation. This study tested the hypothesis that lower PP-MPAP ratio was associated with left ventricular (LV) distension in patients with cardiogenic shock who underwent extracorporeal life support (ECLS). This is a retrospective observational single-centre study of 22 patients with cardiogenic shock who underwent ECLS as the primary support modality without and with LV distension and Impella unloading. The relationship between post-support PP-MPAP and 12-hour lactate clearance was also assessed. Of the 22 patients: 10 patients underwent additional Impella unloading due to LV distension (Group 1) and 12 patients on ECLS only without LV distension (Group 2). As predicted by the theoretical model, PP-MPAP on ECLS dropped in Group 1 (pre-Impella) from 0.473 ± 0.067 to 0.372 ± 0.087, p < 0.001; but increased in Group 2 patients without LV distension (0.518 ± 0.070 to 0.549 ± 0.072, p = 0.002). Impella support in Group 1 increased PP-MPAP (0.372 ± 0.087 to 0.615 ± 0.094, p < 0.001). On multiple regression analysis, post-support PP-MPAP was significantly associated with 12-hour lactate clearance. Changes in PP-MPAP is associated hemodynamic response to ECLS and 12-hour lactate clearance. This simple parameter may guide therapeutic optimization in cardiogenic shock and ECLS.

Abstract 332: Does Concomitant Left Ventricular Unloading Improve Outcomes Of Cardiogenic Shock Managed By Venoarterial Extracorporeal Membrane Oxygenation? Analysis Of National Inpatient Sample Database 2019

Introduction: Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is often used in patients with cardiogenic shock. However, this strategy can lead to left ventricular (LV) distention, thus compromising myocardial recovery. Therefore, concomitant LV unloading with an Impella device (Abiomed, Danvers, MA) has gained a wide interest to promote LV recovery. We aimed to investigate the in-hospital outcomes of patients with myocardial infarction and cardiogenic shock undergoing VA-ECMO with Impella (ECPELLA) versus VA-ECMO alone. Methods: We conducted a retrospective cohort study using the 2019 National Inpatient Sample Database. Variables were identified using their International Classification of Diseases, 10th revision (ICD-10) codes. Descriptive bivariate and multivariate analyses were performed. A p-value &lt;0.05 was considered statistically significant. Results: A total of 1915 records of acute myocardial infarction and cardiogenic shock treated with VA-ECMO were identified. Of these, 625 underwent ECPELLA, and 1,290 underwent VA-ECMO alone. Baseline characteristics and complication rates are listed in Table 1. Inpatient mortality rate was not statistically different between the ECPELLA and the VA-ECMO groups [50.4% (n=315) vs 46.1% (n=595), respectively, p=0.08]. In addition, a multivariable logistic regression model adjusting for potential confounders (baseline characteristics in Table 1, as well as primary expected payer, left heart catheterization, and initial presentation with cardiac arrest) did not show a mortality benefit for ECPELLA over VA-ECMO (OR 1.206, 95% CI 0.967-1.50, p=0.097). However, rates of acute renal failure requiring hemodialysis and intracranial hemorrhage were lower in the ECPELLA group. Conclusion: Our data suggests that there is no survival to hospital discharge benefit for ECPELLA vs VA-ECMO. Prospective studies are warranted to validate our findings. .

Left Atrial Veno-Arterial Extracorporeal Membrane Oxygenation Case Series: A Single-Center Experience

IntroductionWe aimed to review the characteristics and outcomes of left atrial veno-arterial extra corporeal membrane oxygenation (LAVA ECMO) at our institution over a 4-y period from 2017 to 2020. MethodsAmong 227 adult patients who received VA ECMO support from January 2017 to December 2020, we reviewed 33 of these who underwent transseptal cannulation and were converted to LAVA ECMO. The timing of transseptal cannulation, either at initiation of VA ECMO (n = 25) or with a later transseptal cannulation to treat complications of left ventricular (LV) distention while on VA ECMO (n = 8), was reviewed. The clinical characteristics, indications, echocardiography data, and outcomes were assessed. ResultsDuration of LAVA ECMO support ranged from 1 to 13 d, with a median of 5 d. Successful weaning from the LAVA ECMO circuit was achieved for 15 patients (45%). The in-hospital mortality rate was 66%. There were 11 patients (33%) who survived to be discharged from the hospital. ConclusionsLV distention is a known complication of VA ECMO and impedes the recovery of the heart. LAVA ECMO provides a novel approach to treating LV distention. Additionally, our review shows that this modality may be used as a bridge to durable mechanical circulatory support, cardiac transplantation, or recovery.

Left ventricular venting during extracorporeal membrane oxygenation; the effects on cardiac performance in a porcine model of critical post-cardiotomy failure.

Left ventricular distension is a major concern with postcardiotomy veno-arterial extracorporeal membrane oxygenation (VA-ECMO) supporting a critical heart failure after cardiac surgery. This porcine study evaluates the effects of left ventricular venting on cardiac function during ECMO-supported circulation and after weaning from ECMO. Twenty anaesthetised open-chest pigs were put on cardiopulmonary bypass with aortic cross-clamping and suboptimal cardioplegic arrest for 40min. After declamping and defibrillation, the animals were supported by VA-ECMO for 180min either with or without additional left ventricular venting. Continuous haemodynamic evaluations were performed at baseline and at cardiac arrest, during VA-ECMO and for 120min after weaning from circulatory support. Left ventricular perfusion and function were evaluated with microspheres, pressure-volume loops and epicardial echocardiography at baseline and after 1 and 2h with unsupported circulation. In vented animals both mean aortic and left ventricular peak systolic pressure increased at the end of the ECMO-supported period compared to those not vented and remained increased also after weaning. Both at 60 min and 120min after weaning from circulatory support, left ventricular stroke work and pressure-volume area were increased in vented compared to not vented animals. At 120min left ventricular stroke volume was increased in vented compared to not vented animals, myocardial perfusion did not differ. The left ventricular mechanical efficiency, defined as the ratio between pressure volume area and myocardial perfusion, was increased (53.2 ± 5 vs 36.2 ± 2.1J/mL/g, p = 0.011) in vented- compared to not vented hearts. This experimental study demonstrate that left ventricular venting during post-cardiotomy veno-arterial ECMO for 3h attenuates deterioration of left ventricular function and haemodynamics early after weaning from circulatory support.

Current status and future trends of left ventricular decompression strategies in veno-arterial extracorporeal membrane oxygenation

Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is a great weapon to save patients with acute heart failure. At present, in most cases, VA-ECMO is perfused through femoral artery intubation, and the external blood flow is opposite to the direction of cardiac ejection, which will increase the left ventricular afterload and lead to left ventricular expansion, which is not conducive to the recovery of cardiac function. This paper reviews the development course of left ventricular decompression at home and abroad, summarizes the present situation of left ventricular decompression technology at home and abroad, analysis of left ventricular decompression technology advantages and existing problems, and put forward their own opinions, to analyze the prevention and solution of left ventricular distension in VA-ECMO, may explore better method, improve the success rate of treatment in patients with heart failure.

Left Atrial Decompression in Pediatric Patients Supported With Extracorporeal Membrane Oxygenation for Failure to Wean From Cardiopulmonary Bypass: A Propensity-Weighted Analysis.

Background Left atrial (LA) decompression on extracorporeal membrane oxygenation (ECMO) can reduce left ventricular distension, allowing myocardial rest and recovery, and protect from lung injury secondary to cardiogenic pulmonary edema. However, clinical benefits remain unknown. We sought to evaluate the association between LA decompression and in-hospital adverse outcome (mortality, transplant on ECMO, or conversion to ventricular assist device) in patients who failed to wean from cardiopulmonary bypass using a propensity score to adjust for baseline differences. Methods and Results Children (aged <18years) with biventricular physiology supported with ECMO for failure to wean from cardiopulmonary bypass after cardiac surgery from 2000 through 2016, reported to the ELSO (Extracorporeal Life Support Organization) Registry, were included. Inverse probability of treatment weighted logistic regression was used to test the association between LA decompression and in-hospital adverse outcomes. Of the 2915 patients supported with venoarterial ECMO for failure to wean from cardiopulmonary bypass, 1508 had biventricular physiology and 279 (18%) underwent LA decompression (LA+). Genetic and congenital abnormalities (P=0.001) and pulmonary hypertension (P=0.010) were less frequent and baseline arrhythmias (P=0.022) were more frequent in LA+ patients. LA+ patients had longer pre-ECMO mechanical ventilation and CBP time (P<0.001), and used aortic cross-clamp (P=0.001) more frequently. Covariates were well balanced between the propensity-weighted cohorts. In-hospital adverse outcomes occurred in 47% of LA+ patients and 51% of the others. Weighted multivariate logistic regression showed LA decompression to be protective for in-hospital adverse outcomes (adjusted odds ratio, 0.775 [95% CI, 0.644-0.932]). Conclusions LA decompression independently decreased the risk of in-hospital adverse outcome in pediatric venoarterial ECMO patients who failed to wean from cardiopulmonary bypass, suggesting that these patients may benefit from LA decompression.

Subclavian versus femoral arterial cannulations during extracorporeal membrane oxygenation: A propensity-matched comparison.

During peripheral extracorporeal veno-arterial membrane oxygenation (VA-ECMO) support, subclavian arterial cannulation provides, in comparison to femoral arterial cannulation, an anterograde flow which may prevent from left ventricular (LV) distention and improve outcomes. We aimed to compare the effectiveness of subclavian cannulation to femoral cannulation in reducing LV overdistension consequences, hemostatic complications and mortality. This retrospective study conducted in two intensive care units of the Lille academic hospitals from January 2013 to December 2019 included 372 non-moribund adult patients supported by VA-ECMO. The primary endpoint was a new onset of pulmonary edema (PO) or LV unloading. Secondary endpoints were myocardial recovery, serious bleeding (according to Extracorporeal Life Support Organization definition), thrombotic complications (a composite of stroke, cannulated limb or mesenteric ischemia, intracardiac or aortic-root thrombosis) and 28 day mortality. Differences in outcomes were analyzed using propensity score matching (PSM) and inverse probability of treatment weighting adjustment (IPTW). As compared to femoral cannulation (n=320 patients), subclavian cannulation (n=52 patients) did not reduce the occurrence of new onset of PO or LV unloading after PSM [HR 0.99 (95% CI 0.51-1.91)]. There was no other difference in outcomes in PSM cohort. In IPTW adjustment cohort, subclavian cannulation was associated with reduced recovery and increased serious bleeding with four accidental decannulations observed. Subclavian artery cannulation was not associated with reduced LV distension related complications, thrombotic complications and 28 day mortality. Rather, it may increase serious bleeding and accidental decannulations, and reduce recovery. Therefore, subclavian cannulation should be limited to vascular accessibility issues.

Intra‐Aortic Balloon Pump for Left Ventricular Unloading in Veno‐Arterial Extracorporeal Membrane Oxygenation: The Last Remaining Indication in Cardiogenic Shock

Intra‐Aortic Balloon Pump for Left Ventricular Unloading in Veno‐Arterial Extracorporeal Membrane Oxygenation: The Last Remaining Indication in Cardiogenic Shock

Impact of Left Ventricular Unloading Under Circulatory Support with Venoarterial ECMO in Heart Failure Animal Model

<h3>Purpose</h3> An additional left ventricular (LV) unloading device could be effective for LV distension caused by V-A ECMO. However, the appropriate flow proportion between V-A ECMO and LV unloading devices has still been controversial. The purpose of this study was to evaluate the effect of flow proportion between V-A ECMO and LV unloading. <h3>Methods</h3> Microsphere was injected to the left anterior descending artery of 12 adult sheep to induce myocardial ischemia, aiming at the criteria of cardiac output to be less than 50% of that before the microsphere injection. V-A ECMO was established between the right atrium and the abdominal aorta. LV unloading was performed by venting blood from LV apex to the abdominal aorta using a centrifugal pump. V-A ECMO support and LV unloading were maintained for 6 hours with a total systemic flow to be 80-100ml/kg/min. We categorized into 3 groups based on different mechanical circulatory configurations and flow proportion: No LV unloading group (V-A ECMO without LV unloading), Low LV unloading group (LV unloading with V-A ECMO, ECMO: LV venting=3:1), and High LV unloading group (LV unloading with V-A ECMO, ECMO: LV venting=1:1). The LV and right ventricle (RV) functions of these 3 groups were investigated by analyzing hemodynamic parameters as well as the evaluation of LV pressure-volume loops and echocardiography. <h3>Results</h3> During the V-A ECMO support, LVEDP and potential energy of Low and High LV unloading groups were significantly lower than that of No LV unloading group (Figure1A). The RVDd/ LVDd ratio on echocardiography of High LV unloading group was higher than that of Low LV unloading group, while RVFAC of High LV unloading group was lower than that of Low LV unloading group (Figure 1B), suggesting that high LV unloading could be related to RV dysfunction. <h3>Conclusion</h3> LV unloading is mandatory for V-A ECMO in avoiding LV dysfunction, whereas excessive LV unloading has the possibility to cause RV dysfunction.

Mechanical Left Ventricular Unloading in Patients Undergoing Venoarterial Extracorporeal Membrane Oxygenation

BackgroundVenoarterial extracorporeal membrane oxygenation (VA-ECMO) increases left ventricular (LV) afterload, potentially provoking LV distention and impairing recovery. LV mechanical unloading (MU) with intra-aortic balloon pump (IABP) or percutaneous ventricular assist device (pVAD) can prevent LV distension, potentially at the risk of more complications, and net clinical benefit remains uncertain. ObjectivesThis study aims to determine the association between MU and outcomes for patients undergoing VA-ECMO. MethodsThe authors queried the Extracorporeal Life Support Organization registry for adults receiving peripheral VA-ECMO from 2010 to 2019 and stratified them by MU with IABP or pVAD. The primary outcome was in-hospital mortality; secondary outcomes included on-support mortality and complications during VA-ECMO. ResultsAmong 12,734 VA-ECMO patients, 3,399 (26.7%) received MU: 2,782 (82.9%) IABP and 580 (17.1%) pVAD. MU patients were older (age 56.3 vs 52.7 years) and, before extracorporeal membrane oxygenation, more often required >2 vasopressors (41.7% vs 27.2%) and had respiratory (21.1% vs 15.9%), renal (24.6% vs 15.8%), and liver failure (4.4% vs 3.1%) (all P < 0.001). MU patients had lower in-hospital mortality (56.6% vs 59.3%, P = 0.006), which persisted in multivariable modeling (adjusted OR [aOR]: 0.84; 95% CI: 0.77-0.92; P < 0.001). MU was associated with more cannula site bleeding (aOR: 1.25; 95% CI: 1.11-1.40; P < 0.001) and hemolysis (aOR: 1.27; 95% CI: 1.03-1.57; P = 0.02). Compared to pVAD, MU patients with IABP had similar mortality (aOR: 0.80; 95% CI: 0.64-1.01; P = 0.06) and less medical bleeding (aOR: 0.45; 95% CI: 0.31-0.64; P < 0.001), cannula site bleeding (aOR: 0.72; 95% CI: 0.54-0.96; P = 0.03), and renal injury (aOR: 0.78; 95% CI: 0.62-0.98; P = 0.03). ConclusionsAmong adults receiving VA-ECMO, MU was associated with lower in-hospital mortality despite increased complications including hemolysis and cannulation site bleeding. Compared to pVAD, MU with IABP was associated with similar mortality and lower complication rates.