Venoarterial extracorporeal membrane oxygenation for postcardiotomy cardiogenic shock-A six-year service evaluation

Mortality in patients with normal left ventricular function requiring emergency VA-ECMO for postcardiotomy cardiogenic shock due to coronary malperfusion

OBJECTIVES

To analyze outcomes in patients with normal preoperative left ventricular ejection fraction (LVEF) undergoing venoarterial extracorporeal membrane oxygenation (VA-ECMO) therapy due to postcardiotomy cardiogenic shock (PCCS) related to coronary malperfusion.

METHODS

Retrospective single-center analysis in patients with normal preoperative LVEF treated with VA-ECMO for coronary malperfusion-related PCCS between May 1998 and May 2018. The primary outcome was 30-day mortality, which was compared using the Kaplan-Meier method and the log-rank test. Multivariable logistic regression was performed to identify predictors of mortality.

RESULTS

During the study period, a total of 62,125 patients underwent cardiac surgery at our institution. Amongst them, 59 patients (0.1%) with normal preoperative LVEF required VA-ECMO support due to coronary malperfusion-related PCCS. The mean duration of VA-ECMO support was 6 days (interquartile range 4-7 days). The 30-day mortality was 50.8%. Under VA-ECMO therapy, a complication composite outcome of bleeding, re-exploration for bleeding, acute renal failure, acute liver failure, and sepsis occurred in 51 (86.4%) patients. Independent predictors of 30-day mortality were lactate levels > 9.9 mmol/l before VA-ECMO implantation (odds ratio [OR]: 3.3; 95% confidence interval [CI] 1.5-7.0; p = 0.002), delay until revascularization > 278 minutes (OR: 2.9; 95% CI 1.3-6.4; p = 0.008) and peripheral arterial artery disease (OR: 3.3; 95% 1.6-7.5; p = 0.001).

CONCLUSIONS

Mortality rates are high in patients with normal preoperative LVEF who develop PCCS due to coronary malperfusion. The early implantation of VA-ECMO before the development of profound tissue hypoxia and early coronary revascularization increases the likelihood of survival. Lactate levels are useful to define optimal timing for the VA-ECMO initiation.

Patient and Management Variables Associated With Survival After Postcardiotomy Extracorporeal Membrane Oxygenation in Adults: The PELS-1 Multicenter Cohort Study

Background Extracorporeal membrane oxygenation (ECMO) has been increasingly used for postcardiotomy cardiogenic shock, but without a concomitant reduction in observed in-hospital mortality. Long-term outcomes are unknown. This study describes patients' characteristics, in-hospital outcome, and 10-year survival after postcardiotomy ECMO. Variables associated with in-hospital and postdischarge mortality are investigated and reported. Methods and Results The retrospective international multicenter observational PELS-1 (Postcardiotomy Extracorporeal Life Support) study includes data on adults requiring ECMO for postcardiotomy cardiogenic shock between 2000 and 2020 from 34 centers. Variables associated with mortality were estimated preoperatively, intraoperatively, during ECMO, and after the occurrence of any complications, and then analyzed at different time points during a patient's clinical course, through mixed Cox proportional hazards models containing fixed and random effects. Follow-up was established by institutional chart review or contacting patients. This analysis included 2058 patients (59% were men; median [interquartile range] age, 65.0 [55.0-72.0] years). In-hospital mortality was 60.5%. Independent variables associated with in-hospital mortality were age (hazard ratio [HR], 1.02 [95% CI, 1.01-1.02]) and preoperative cardiac arrest (HR, 1.41 [95% CI, 1.15-1.73]). In the subgroup of hospital survivors, the overall 1-, 2-, 5-, and 10-year survival rates were 89.5% (95% CI, 87.0%-92.0%), 85.4% (95% CI, 82.5%-88.3%), 76.4% (95% CI, 72.5%-80.5%), and 65.9% (95% CI, 60.3%-72.0%), respectively. Variables associated with postdischarge mortality included older age, atrial fibrillation, emergency surgery, type of surgery, postoperative acute kidney injury, and postoperative septic shock. Conclusions In adults, in-hospital mortality after postcardiotomy ECMO remains high; however, two-thirds of those who are discharged from hospital survive up to 10 years. Patient selection, intraoperative decisions, and ECMO management remain key variables associated with survival in this cohort. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03857217.

Venoarterial extracorporeal membrane oxygenation with intra-aortic balloon pump for postcardiotomy cardiogenic shock: A systematic review and meta-analysis

OBJECTIVE

Intra-aortic balloon pump (IABP) is currently recommended as a strategy to address the increased afterload in patients who received venoarterial extracorporeal membrane oxygenation (VA-ECMO). The benefit of VA-ECMO with IABP in postcardiotomy cardiogenic shock is inconclusive. A systematic review and meta-analysis was conducted to assess the influence of VA-ECMO with IABP for postcardiotomy cardiogenic shock (PCS).

METHODS

The Cochrane Library, PubMed, and Embase were searched for all articles published from 1 January, 1964 to July 11, 2020. Retrospective cohort studies targeting the comparison of VA-ECMO with IABP and isolated VA-ECMO were included in this study.

RESULTS

We included 2251 patients in the present study (917 patients in the VA-ECMO with IABP group and 1334 patients in the isolated VA-ECMO group). Deaths occurred in 589 of 917 patients (64.2%) in the VA-ECMO with IABP group and occurred in 885 of 1334 patients (66.3%) in isolated VA-ECMO group. Pooling the results of all studies showed that VA-ECMO with IABP was not related to a reduced in-hospital mortality in patients who received VA-ECMO for PCS (RR, 0.95; 95% CI, 0.86-1.04; p = 0.231). In addition, VA-ECMO with IABP was not related to an increased rate of VA-ECMO weaning in patients who received VA-ECMO for PCS (RR, 1.28; 95% CI, 0.99-1.66; p = 0.058).

CONCLUSIONS

This study indicates that VA-ECMO with IABP did not improve either in-hospital survival or weaning for VA-ECMO in postcardiotomy cardiogenic shock patients.

Bleeding and Thrombotic Events During Extracorporeal Membrane Oxygenation for Postcardiotomy Shock

BACKGROUND

Anticoagulation therapy management during venoarterial extracorporeal membrane oxygenation (ECMO) is particularly difficult in postcardiotomy shock patients given a significant bleeding risk. We sought to determine the effect of anticoagulation treatment on bleeding and thrombosis risk for postcardiotomy shock patients on ECMO.

METHODS

We retrospectively reviewed patients who received ECMO for postcardiotomy shock from July 2007 through July 2019. Characteristics of patients who had bleeding and thrombosis were investigated, and risk factors were assessed by multilevel logistic regression.

RESULTS

Of the 152 patients who received ECMO for postcardiotomy shock, 33 (23%) had 40 thrombotic events and 64 (45%) had 86 bleeding events. Predictors of bleeding were intraoperative packed red blood cell transfusion (odds ratio [OR] 1.05; 95% confidence interval [CI], 1.01 to 1.09), platelet transfusion (OR 1.10; 95% CI, 1.05 to 1.16), international normalized ratio (OR 1.18; 95% CI, 1.02 to 1.37), and activated partial thromboplastin time greater than 60 seconds (OR 2.32; 95% CI, 1.14 to 4.73). Predictors of thrombosis were anticoagulant use (OR 0.39; 95% CI, 0.19 to 0.79), surgical venting (OR 3.07; 95% CI, 1.29 to 7.31), hemoglobin (OR 1.38; 95% CI, 1.06 to 1.79), and central cannulation (OR 2.06; 95% CI, 1.03 to 4.11). The daily predicted probability of thrombosis was between 0.075 and 0.038 for patients who did not receive anticoagulation and decreased to between 0.030 and 0.013 for patients who received anticoagulation treatment at activated partial thromboplastin times between 25 and 80 seconds.

CONCLUSIONS

Anticoagulation therapy can reduce thromboembolic events in postcardiotomy shock patients on ECMO, but bleeding risk may outweigh this benefit at activated partial thromboplastin times greater than 60 seconds.

Emergency biventricular assist device implantation in a patient with suspected COVID-19 disease

Severe coronavirus disease 2019 (COVID-19) is a multisystem inflammatory disorder and knowledge and experience with severe acute respiratory failure in infected patients has grown considerably since reports of the first few cases. Little is known about the effect of the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) virus on the heart, and it has been suggested that fulminant cardiac failure, with or without respiratory failure, may occur several weeks following infection. A young man presented after a recent viral illness. He was in severe cardiogenic shock and was implanted with an emergency biventricular assist device, which also incorporated an extracorporeal membrane oxygenator. He stabilised soon after and, despite an intracerebral haemorrhage which resolved and bleeding into the trachea following percutaneous tracheostomy, he survived to explant and was successfully stepped down to a rehabilitation unit on postoperative day 50. He tested positive for SARS-CoV-2 antibodies when the test became available on postoperative day 33. We envisage there will be many more such presentations of acute COVID-19-associated cardiogenic shock and we recommend clinicians consider this diagnosis when presented with an acutely unwell patient with an unclear diagnosis following a viral illness. These patients should be discussed as early as possible with a transplant/mechanical circulatory support team.

The challenges of venoarterial extracorporeal membrane oxygenation for postcardiotomy cardiogenic shock

Postcardiotomy cardiogenic shock describes the syndrome of refractory cardiac performance following cardiac surgery. The use of venoarterial extracorporeal membrane oxygenation (VA-ECMO) for the management of postcardiotomy cardiogenic shock is controversial, and there are at least three scenarios where it may be necessary: first, pre-emptive postoperative VA-ECMO, where the decision for postoperative mechanical support is made prior to surgery, for example, in the context of poor pre-operative cardiac function; second, early yet unplanned post-cardiopulmonary bypass VA-ECMO following a long duration of cardiopulmonary bypass due to, for example, unexpected surgical complications; third, late rescue VA-ECMO following several attempts at weaning, either immediately following cardiopulmonary bypass or following transfer to the intensive care unit. The use of mechanical circulatory support for postcardiotomy cardiogenic shock is further complicated by the wide range of available devices, the availability of VA-ECMO in different centres, variations in experience and expertise as a function of local VA-ECMO workload, and regional variations in the diagnosis and management of postcardiotomy cardiogenic shock. Furthermore, survival appears to be low for such patients and it is not yet possible to predict who will survive. Many questions remain, however, such as those in relation to practices around patient selection, how best to study long-term outcomes, the ethics and efficacy of ECMO in such patients, and on all aspects of clinical decision-making. This review sets these clinical challenges in the context of the available evidence, including that from our centre.

Outcomes and factors associated with early mortality in pediatric postcardiotomy veno-arterial extracorporeal membrane oxygenation

Mortality and morbidity of children received veno-arterial extracorporeal membrane oxygenation (VA-ECMO) support after cardiac surgery remain high despite remarkable advances in medical management and devices. The purpose of this study was to describe outcomes and risk factors of applying VA-ECMO in the surgical pediatric population. We retrospectively analyzed 85 consecutive pediatric patients (aged <18 years) who received postcardiotomy VA-ECMO from January 2010 to December 2018. Median (IQR) age at ECMO implantation in this cohort was 12.7 (6.4, 43.2) months, median weight was 8.5 (6.0, 12.8) kg, mean ECMO duration was 143.2 ± 81.6 hours and mean hospital length of stay was 48.4 ± 32.4 days. Seventy-five patients (88.2%) were indicated for postcardiotomy cardiogenic shock. The successful ECMO weaning rate was 70.6% and in-hospital mortality was 52.9%. The most common diagnosis was transposition of great arteries (n = 18, 21.2%), while acute kidney injury occurred most often (n = 64, 75.3%). Multivariate logistic regression analysis showed that thrombocytopenia, hemolysis, and nosocomial infection were positively correlated with in-hospital mortality. Multivariate Cox proportional hazard regression analysis presented that thrombocytopenia significantly increased the 180-day mortality in patients with successful weaning. Therefore, multiple factors had adverse effects on prognosis. Patient selection and procedures from ECMO implantation to weaning need to be closely monitored and performed in a timely manner to improve outcome.