Extracorporeal membrane oxygenation (ECMO) is life-saving for potentially reversible heart failure and respiratory injuries not responsive to conventional therapies. Technological innovations have produced over the years significant improvements in ECMO devices (pump, cannula design and oxygenator) and have allowed a better risk/benefit profile. Alongside with recognized advantages in the treatment of very sick patients, ECMO remains an invasive procedure for mechanical circulatory support (MCS) and it is associated with complications that strongly influence the prognosis. Current review was designed to provide a comprehensive outline on ECMO complications, analyzing risk factors and strategies of management, focusing on adult population undergoing veno-arterial ECMO (VA-ECMO) therapy.

OBJECTIVES: Refractory postcardiotomy cardiogenic shock complicating cardiac surgery yields nearly 100% mortality when untreated. Use of venoarterial extracorporeal membrane oxygenation for postcardiotomy cardiogenic shock has increased worldwide recently. The aim of the current analysis was to outline the trends in use, changing patient profiles, and in-hospital outcomes including complications in patients undergoing venoarterial extracorporeal membrane oxygenation for postcardiotomy cardiogenic shock. DESIGN: Analysis of extracorporeal life support organization registry from January 2010 to December 2018. SETTING: Multicenter worldwide registry. PATIENTS: Seven-thousand one-hundred eighty-five patients supported with venoarterial extracorporeal membrane oxygenation for postcardiotomy cardiogenic shock. INTERVENTIONS: Venoarterial extracorporeal membrane oxygenation. MEASUREMENTS AND MAIN RESULTS: Hospital death, weaning from extracorporeal membrane oxygenation, hospital complications. Mortality predictors were assessed by multivariable logistic regression. Propensity score matching was performed for comparison of peripheral and central cannulation for extracorporeal membrane oxygenation. A significant trend toward more extracorporeal membrane oxygenation use in recent years (coefficient, 0.009; p < 0.001) was found. Mean age was 56.3 ± 14.9 years and significantly increased over time (coefficient, 0.513; p < 0.001). Most commonly, venoarterial extracorporeal membrane oxygenation was instituted after coronary artery bypass surgery (26.8%) and valvular surgery (25.6%), followed by heart transplantation (20.7%). Overall, successful extracorporeal membrane oxygenation weaning was possible in 4,520 cases (56.4%), and survival to hospital discharge was achieved in 41.7% of cases. In-hospital mortality rates remained constant over time (coefficient, –8.775; p = 0.682), whereas complication rates were significantly reduced (coefficient, –0.009; p = 0.003). Higher mortality was observed after coronary artery bypass surgery (65.4%), combined coronary artery bypass surgery with valve (68.4%), and aortic (69.6%) procedures than other indications. Lower mortality rates were observed in heart transplantation recipients (46.0%). Age (p < 0.001), central cannulation (p < 0.001), and occurrence of complications while on extracorporeal membrane oxygenation were independently associated with poorer prognosis. CONCLUSIONS: The analysis confirmed increased use of venoarterial extracorporeal membrane oxygenation for postcardiotomy cardiogenic shock. Mortality rates remained relatively constant over time despite a decrease in complications, in the setting of supporting older patients.

During veno-arterial extracorporeal membrane oxygenation (VA-ECMO), the increase of left ventricular (LV) afterload can potentially increase the LV stress, exacerbate myocardial ischemia and delay recovery from cardiogenic shock (CS). Several strategies of LV unloading have been proposed. Systematic review and meta-analysis in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement included adult patients from studies published between January 2000 and March 2019. The search was conducted through numerous databases. Overall, from 62 papers, 7581 patients were included, among whom 3337 (44.0%) received LV unloading concomitant to VA-ECMO. Overall, in-hospital mortality was 58.9% (4466/7581). A concomitant strategy of LV unloading as compared to ECMO alone was associated with 12% lower mortality risk (RR 0.88; 95% CI 0.82-0.93; p < 0.0001; I 2 = 40%) and 35% higher probability of weaning from ECMO (RR 1.35; 95% CI 1.21-1.51; p < 0.00001; I 2 = 38%). In an analysis stratified by setting, the highest mortality risk benefit was observed in case of acute myocardial infarction: RR 0.75; 95%CI 0.68-0.83; p < 0.0001; I 2 = 0%. There were no apparent differences between two techniques in terms of complications. In heterogeneous populations of critically ill adults in CS and supported with Abstract Structured summary 2Provide a structured summary including, as applicable: background; objectives; data sources; study eligibility criteria, participants and interventions; study appraisal and synthesis methods; results; limitations; conclusions and implications of key findings; systematic review registration number.

Background: Postcardiotomy cardiogenic shock (PCS) that is refractory to inotropic support remains a major concern in cardiac surgery and is almost universally fatal unless treated with mechanical support. While reported mortality rates on ECMO vary from center to center, aim of the current report is assess if the outcomes differ between centres according to volume and heart transplantation status. Methods: A systematic search was performed according to PRISMA statement using PubMed/Medline databases between 2010 and 2018. Relevant articles were scrutinized and included in the meta-analysis only if reporting inhospital/30-day mortality and heart transplantation status of the centre. Paediatric and congenital heart surgeryrelated studies along with those conducted in the setting of veno-venous ECMO for respiratory distress syndrome were excluded. Differences were assessed by means of subgroup meta-analysis and meta-regression. Results: Fifty-four studies enrolling N = 4421 ECMO patients were included. Of those, 6 series were performed in non-HTx centres (204 pts.;4.6%). Overall 30-day survival (95% Confidence Intervals) was 35.3% (32.5-38.2%) and did not statistically differ between non-HTx: 33.3% (26.8-40.4%) and HTx centres: 35.7% (32.7-38.8%); P interaction = 0.531. There was no impact of centre volume on survival as well: ß coef = 0.0006; P = 0.833. No statistical differences were seen between HTx and non-HTx with respect to ECMO duration, limb complications, reoperations for bleeding, kidney injury and sepsis. There were however significantly less neurological complications in the HTx as compared to non-HTx centres: 11.9% vs 19.5% respectively; P = 0.009; an inverse relationship was seen for neurologic complications in centres performing more ECMOs annually ß coef = − 0.0066; P = 0.031. Weaning rates and bridging to HTx and/or VADs were higher in HTx facilities. Conclusions: There was no apparent difference in survival after ECMO implantation for refractory PCS according to centre's ECMO volume and transplantation status. Potentially different risk profiles of patients in these centres must be taken account for before definite conclusions are drawn.

Aims Because reported mortality on veno-arterial (V-A) extracorporeal life support (ECLS) substantially varies between centres, the aim of the current analysis was to assess the outcomes between units performing heart transplantation and/or implanting ventricular assist device (HTx/VAD) vs. non-HTx/VAD units in patients undergoing V-A ECLS for cardiogenic shock. Methods and results Systematic search according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses was performed using PubMed/MEDLINE databases until 30 November 2019. Articles reporting in-hospital/ 30-day mortality and centre's HTx/VAD status were included. In-hospital outcomes and long-term survival were analysed in subgroup meta-analysis. A total of 174 studies enrolling n = 13 308 patients were included with 20 series performed in non-HTx/VAD centres (1016 patients, 7.8%). Majority of patients underwent V-A ECLS for post-cardiotomy shock (44.2%) and acute myocardial infarction (20.7%). Estimated overall in-hospital mortality was 57.2% (54.9-59.4%). Mortality rates were higher in non-HTx/VAD [65.5% (59.8-70.8%)] as compared with HTx/VAD centres [55.8% (53.3-58.2%)], P < 0.001. Estimated late survival was 61.8% (55.7-67.9%) without differences between non-HTx/VAD and HTx/VAD centres: 66.5% (30.3-1.02%) vs. 61.7% (55.5-67.8%), respectively (P = 0.797). No differences were seen with respect to ECLS duration, limb complications, and reoperations for bleeding, kidney injury, and sepsis. Yet, weaning rates were higher in HTx/VAD vs. non-HTx/VAD centres: 58.7% (56.2-61.1%) vs. 48.9% (42.0-55.9%), P = 0.010. Estimated rate of bridge to heart transplant was 6.6% (5.2-8.3%) with numerical, yet not statistically significant, difference between non-HTx/VAD [2.7% (0.8-8.3%)] as compared with HTx/VAD [6.7% (5.3-8.6%)] (P = 0.131). Conclusions Survival after V-A ECLS differed according to centre's HTx/VAD status. Potentially different risk profiles of patients must be taken account for before definite conclusions are drawn.