Perioperative Risk Factors of Acute Kidney Injury After Heart Transplantation and One-Year Clinical Outcomes: A Retrospective Cohort Study.

OBJECTIVES: This study aimed to identify perioperative risk factors of acute kidney injury after heart transplantation and to evaluate 1-year clinical outcomes. DESIGN: A retrospective single-center cohort study. SETTING: At a university hospital. PARTICIPANTS: All patients who underwent heart transplantation from January 2015 to December 2020. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The authors recorded acute kidney injury after heart transplantation. One-year mortality and renal function also were recorded. Risk factors of acute kidney injury were evaluated using a multivariate logistic regression model. Long-term survival was compared between patients developing acute kidney injury and those who did not, using a log-rank test. Among 209 patients included in this study, 134 patients (64% [95% CI (58; 71)]) developed posttransplantation acute kidney injury. Factors independently associated with acute kidney injury were high body mass index (odds ratio [OR]: 1.18 [1.02-1.38] per kg/m2; p = 0.030), prolonged duration of cold ischemic period (OR: 1.11 [1.01-1.24] per 10 minutes; p = 0.039), and high dose of intraoperative dobutamine support (OR: 1.24 [1.06-1.46] per µg/kg/min; p = 0.008). At 1 year, patients who developed postoperative acute kidney injury had higher mortality rates (20% v 8%, p = 0.015). Among 172 survivors at 1 year, 82 survivors (48%) had worsened their renal function compared with preheart transplantation. CONCLUSIONS: This study highlighted the high incidence of acute kidney injury after heart transplantation and its impact on patient outcomes. Risk factors such as body mass index, prolonged cold ischemic period duration, and level of inotropic support with dobutamine were identified, providing insights for preventive strategies.

Bleeding complications, coagulation disorders, and their management in acute myocardial infarction-related cardiogenic shock rescued by veno-arterial ECMO: A retrospective cohort study.

PURPOSE: Management of dual antiplatelet therapy (DAPT) in patients on venoarterial-extracorporeal membrane (VA-ECMO) after acute myocardial infarction (AMI) is challenging. Our objective was to describe the frequency, management and outcomes of severe bleeding complications and determine their occurrence risk factors. MATERIAL AND METHODS: We conducted a retrospective observational cohort study including post-AMI cardiogenic shock patients requiring VA-ECMO. Severe bleeding was defined based on the Bleeding Academic Research Consortium classification. We calculated multivariable Fine-Gray models to assess factors associated with risk of severe bleeding. RESULTS: From January 2015 to July 2019, 176 patients received VA-ECMO after AMI and 132 patients were included. Sixty-five (49%) patients died. Severe bleeding occurred in 39% of cases. Severe thrombocytopenia (< 50 G/L) and hypofibrinogenemia (<1,5 g/L) occurred in respectively 31% and 19% of patients. DAPT was stopped in 32% of patients with a 6% rate of stent thrombosis. Anticoagulation was stopped in 39% of patients. Using a multivariate competing risk model, female sex, time on ECMO, troponin at admission and Impella® implantation were independently associated with severe bleeding. CONCLUSIONS: Bleeding complications and coagulation disorders were frequent and severe in patients on VA-ECMO after AMI, leading of antiplatelet therapy withdrawal in one third of patients.

Lactate-Based Difference as a Determinant of Outcomes following Surgery for Type A Acute Aortic Dissection: A Multi-Centre Study.

Type A acute aortic dissection (TAAAD) is a serious condition within the acute aortic syndromes that demands immediate treatment. Despite advancements in diagnostic and referral pathways, the survival rate post-surgery currently sits at almost 20%. Our objective was to pinpoint clinical indicators for mortality and morbidity, particularly raised arterial lactate as a key factor for negative outcomes. METHODS: All patients referred to the three cardiovascular centres between January 2005 and December 2022 were included in the study. The inclusion criteria required the presence of a lesion involving the ascending aorta, symptoms within 7 days of surgery, and referral for primary surgical repair of TAAAD based on recommendations, with consideration for other concomitant major cardiac surgical procedures needed during TAAAD and retrograde extension of TAAAD. We conducted an analysis of both continuous and categorical variables and utilised predictive mean matching to fill in missing numeric features. For missing binary variables, we used logistic regression to impute values. We specifically targeted early postoperative mortality and employed LASSO regression to minimise potential collinearity of over-fitting variables and variables measured from the same patient. RESULTS: A total of 633 patients were recruited for the study, out of which 449 patients had complete preoperative arterial lactate data. The average age of the patients was 64 years, and 304 patients were male (67.6%). The crude early postoperative mortality rate was 24.5% (110 out of 449 patients). The mortality rate did not show any significant difference when comparing conservative and extensive surgeries. However, malperfusion had a significant impact on mortality [48/131 (36.6%) vs. 62/318 (19.5%), p < 0.001]. Preoperative arterial lactates were significantly elevated in patients with malperfusion. The optimal prognostic threshold of arterial lactate for predicting early postoperative mortality in our cohort was ≥2.6 mmol/L. CONCLUSION: The arterial lactate concentration in patients referred for TAAAD is an independent factor for both operative mortality and postoperative complications. In addition to mortality, patients with an upper arterial lactate cut-off of ≥2.6 mmol/L face significant risks of VA ECMO and the need for dialysis within the first 48 h after surgery. To improve recognition and facilitate rapid transfer and surgical treatment protocol, more diligent efforts are required in the management of malperfusion in TAAAD.

Outcomes of aortic valve-sparing root replacement with cusp repair in connective tissue disease.

BACKGROUND: Although, valve sparing is commonly performed in patients with Marfan syndrome, feasibility and results of cusp repair for aortic insufficiency have not been studied. AIM: To report on the outcomes and durability of aortic cusp repair in valve sparing in patients with Marfan syndrome. METHODS: All consecutive adult patients with Marfan syndrome who underwent remodelling and annuloplasty with aortic valve repair for aortic insufficiency between May 2005 and December 2020 were included. Patients with Marfan syndrome treated for aortic aneurysm, but without aortic insufficiency, were excluded. Data were collected prospectively and reviewed retrospectively from the Aorticvalve repair International Registry (AVIATOR). RESULTS: During the study period, 71 patients with Marfan syndrome were referred to surgery. Fifty-five patients with connective tissue disease and aortic insufficiency with aorta aneurysm were treated: 46 underwent aortic valve repair and nine underwent aortic valve replacement (five mechanical aortic valve replacements and four biological aortic valve replacements). The mean age was 42.9±15.4 years, and the mean EuroScore II was 2.5±2.2. No patient died, and no patient had significant aortic insufficiency (grade≥II) at discharge. The 5-year survival rate estimate was 94.4%, which seems statistically similar to that of the age- and sex-matched general population. At 5 years, freedom from reoperation was 94.6%, and the incidence of infective endocarditis was 2.6%. No valve thrombosis, aortic dissection, major bleeding events, thromboembolic events (stroke) or myocardial infarctions were noted during follow-up. CONCLUSION: Remodelling and aortic valve repair showed excellent durability at 5 years, even in connective tissue disorders.

Diagnostic yield, safety and therapeutic consequences of myocardial biopsy in clinically suspected fulminant myocarditis unweanable from mechanical circulatory support.

BACKGROUND: Fulminant myocarditis is a rare and severe disease whose definite and etiological diagnoses rely on pathological examination. Albeit, myocardial biopsy can be associated with significant morbidity and mortality, its therapeutic consequences are unclear. We conducted a study to determine the diagnostic yield, the safety and the therapeutic consequences of myocardial biopsy in patients with fulminant clinically suspected myocarditis unweanable from mechanical circulatory support (MCS). METHODS: Monocenter, retrospective, observational cohort study in a 26-bed French tertiary ICU between January 2002 and February 2019. Inclusion of all fulminant clinically suspected myocarditis patients undergoing in-ICU myocardial biopsy while being on MCS. The primary endpoint was the proportion of patients classified as definite myocarditis using Bonaca criteria before and after including myocardial biopsy results. RESULTS: Forty-seven patients (median age 41 [30-47], female 53%) were included: 55% died before hospital discharge, 34% could be bridged-to-recovery and 15% bridged-to-transplant. Myocardial biopsy was endomyocardial or surgical in 36% and 64% cases respectively. Tamponade requiring emergency pericardiocentesis occurred in 29% patients after endomyocardial biopsy. After adding the biopsy results in the Bonaca classification algorithm the percentage of definite myocarditis raised from 13 to 55% (p < 0.0001). The rate of biopsy-related treatments modifications was 13%, leading to patients' recovery in only 4% patients. CONCLUSIONS: In clinically suspected myocarditis unweanable from MCS, myocardial biopsy increased the rate of definite myocarditis but was associated with a low rate of treatment modification and a significant proportion of adverse events. We believe the benefit/risk ratio of myocardial biopsy should be more carefully weighted in these frail and selected patients than suggested by actual guidelines. Further prospective studies are now needed to determine its value in patients under MCS.

Transportation of patients under extracorporeal membrane oxygenation support on an airliner: Flying bridge to transplantation.

BACKGROUND: A retrieval programme was developed in Martinique (French West Indies) to provide extracorporeal membrane oxygenation for patients in the Caribbean, where heart transplantation and ventricular assist devices are not available. In 2011, the Department of Cardiac Surgery at the University Hospital of Fort-de-France (Martinique) developed a transfer programme to Paris (France) on an airliner, to refer patients for whom extracorporeal membrane oxygenation was not weanable to heart transplantation or a ventricular assist device. AIM: To report this unique experience of transportation of patients under extracorporeal membrane oxygenation support on an airliner from the French West Indies to Paris. METHODS: This was an observational and retrospective study of all patients under extracorporeal membrane oxygenation support who were transferred from Martinique to the Pitié-Salpêtrière Hospital/Sorbonne University in Paris between September 2011 and September 2019. Transport characteristics, complications during repatriation, cost and clinical outcomes at 30days and 1year were reported. RESULTS: Twenty-six patients were transferred on an airliner; the retrieval distance was 7260km, and the mean duration was 14hours. Only two patients developed complications (pulmonary oedema and leg ischaemia), and no patient died during the flight. Nine patients had a ventricular assist device implanted, and six patients were transplanted. Thirty-day survival was 65.4%, and 1-year survival was 38.5%. CONCLUSIONS: Transport under extracorporeal membrane oxygenation support on an airliner is safe and efficient, with an acceptable cost. This programme allowed patients under extracorporeal membrane oxygenation support in a remote centre, without access to transplantation or a ventricular assist device, to be referred for these techniques in specialized centres. This experience strengthens the strategy of developing regional networks around specialized extracorporeal membrane oxygenation centres.

Sudden cardiac death after heart transplantation: a population-based study.

AIMS: The epidemiology of sudden cardiac death (SCD) after heart transplantation (HTx) remains imprecisely described. We aimed to assess the incidence and determinants of SCD in a large cohort of HTx recipients, compared with the general population. METHODS AND RESULTS: Consecutive HTx recipients (n = 1246, 2 centres) transplanted between 2004 and 2016 were included. We prospectively assessed clinical, biological, pathologic, and functional parameters. SCD was centrally adjudicated. We compared the SCD incidence beyond the first year post-transplant in this cohort with that observed in the general population of the same geographic area (registry carried out by the same group of investigators; n = 19 706 SCD). We performed a competing risk multivariate Cox model to identify variables associated with SCD. The annual incidence of SCD was 12.5 per 1,000 person-years [95% confidence interval (CI), 9.7-15.9] in the HTx recipients cohort compared with 0.54 per 1,000 person-years (95% CI, 0.53-0.55) in the general population (P < 0.001). The risk of SCD was markedly elevated among the youngest HTx recipients with standardized mortality ratios for SCD up to 837 for recipients ≤30 years. Beyond the first year, SCD was the leading cause of death. Five variables were independently associated with SCD: older donor age (P = 0.003), younger recipient age (P = 0.001) and ethnicity (P = 0.034), pre-existing donor-specific antibodies (P = 0.009), and last left ventricular ejection fraction (P = 0.048). CONCLUSION: HTx recipients, particularly the youngest, were at very high risk of SCD compared with the general population. The consideration of specific risk factors may help identify high-risk subgroups.

Implication of the new definition of pulmonary hypertension in patients evaluated for heart transplantation.

BACKGROUND: The 2018 World Symposium on Pulmonary Hypertension (WSPH) changed the definition of pulmonary hypertension (PH) with a new threshold of mean pulmonary artery pressure (mPAP) above 20 mmHg. OBJECTIVE: To evaluate the profile and prognosis of patients with chronic heart failure (HF) considered for heart transplantation with the new definition of PH. METHODS: Patients with chronic HF considered for heart transplantation were classified as mPAP≤20mmHg, mPAP 20-25 mmHg, and mPAP≥25mmHg. Using a multivariate Cox model, we compared the mortality of patients with mPAP20-25mmHg, and mPAP≥25mmHg versus those with mPAP≤20mmHg. RESULTS: Of 693 patients with chronic HF considered for heart transplantation, 12.7%, 77.5% and 9.8% were classified as mPAP20-25mmHg, mPAP≥ 25mmHg and mPAP≤20mmHg. Patients of mPAP ≥ 25mmHg and mPAP 20-25 mmHg categories were older than mPAP ≤ 20 mmHg (56 versus 55 and 52 year-old, p = 0.02) with more frequent co-morbidities. Within 2.8 years, the mPAP20-25mmHg category displayed a higher risk of mortality compared with those of the mPAP≤20mmHg category (aHR 2.75, 95% CI 1.27-5.97, p = 0.01). Overall, the new PH definition using a threshold of mPAP >20 mmHg was associated with a higher risk of death (adj HR 2.71, 95% CI 1.26-5.80) than the previous definition (mPAP >25 mmHg, aHR: 1.35 95% CI 1.00-1.83, p = 0.05). CONCLUSIONS: One out of 8 patients with severe HF are reclassified as having PH following the 2018 WSPH. Patients with mPAP20-25 evaluated for heart transplantation displayed significant co-morbidities and high mortality rates.

Practical application of the French two-score heart allocation scheme: Insights from a high-volume heart transplantation centre.

BACKGROUND: In 2018, a cardiac allocation scheme based on an individual score considering the risk of death both on the waitlist and after heart transplantation was implemented in France. AIMS: To analyse the practical application of the pre- and post-transplant risk score in a French high-volume heart transplantation centre. METHODS: All consecutive adult patients listed for a first non-combined heart transplantation between 02 January 2018 and 30 June 2022 at our centre were included. Baseline characteristics of candidates and recipients were retrieved from the national CRISTAL registry. Both scores were calculated at listing and at transplant. RESULTS: Overall, 364 patients were included. During follow-up, 257 patients (70.6%) were transplanted, and 57 (15.6%) died or were removed from the waitlist. Post-transplant 3-month survival was 84.8%. Total bilirubin and natriuretic peptides had the most important weight in the pretransplant risk score. This score had a major impact on waitlist outcomes: quartile 1 was characterized by low access to heart transplantation (58.2%) and risk of death on the waitlist (9.9%) compared with quartile 4 (heart transplantation rate 74.1%, mortality on the waiting list>20%). According to the post-transplant risk score, a minimal number of candidates were considered ineligible for heart transplantation (<1%), but 12.4% were contraindicated to at least one donor category. The number of contraindicated donor categories had a significant impact on waitlist outcomes. Although adequately calibrated, the post-transplant score had a limited discrimination (area under the curve 0.65, 95% confidence interval 0.59-0.71). CONCLUSION: Our results highlight the major impact of pre- and post-transplantation risk scores on waitlist outcomes following the allocation scheme update.

Association between vasoactive-inotropic score, morbidity and mortality after heart transplantation.

OBJECTIVES: The aim of this study was to evaluate the association between vasoactive-inotropic score (VIS), calculated in the 24 h after heart transplantation, and post-transplant mortality and morbidity. METHODS: This was an observational single-centre retrospective study. Patients admitted to surgical intensive care unit after transplantation, between January 2015 and December 2018, were reviewed consecutively. VISmax was calculated as dopamine+ dobutamine+ 100 × epinephrine + 100 × norepinephrine + 50 × levosimendan + 10 × milrinone (all in µg/kg/min) + 10 000 × vasopressin (units/kg/min), using the maximum dosing rates of vasoactive and inotropic medications in the 24 h after intensive care unit admission. The primary outcome was mortality at 1 year post-transplant. The secondary outcomes included length of stay, duration of mechanical ventilation and inotropic support and the occurrence of septic shock, ventilator-associated pneumonia, bloodstream infection or renal replacement therapy. RESULTS: A total of 151 patients underwent heart transplantation and admitted to intensive care unit. The median VISmax was 39.2 (interquartile range = 19.4-83.0). VISmax was independently associated with 1-year post-transplant mortality, as well as recipient age [hazard ratio (HR) = 1.004, P-value = 0.013], recipient gender (female to male: hazard ratio = 2.23, P-value = 0.047) and combined transplantation (hazard ratio = 2.85, P-value = 0.048). There was a significant association between VISmax and duration of mechanical ventilation (P-value < 0.001), length of stay (P-value = 0.002), duration of infused inotropes (P-value < 0.001), occurrence of bloodstream infections, septic shocks, ventilation-acquired pneumonia and renal replacement therapy. CONCLUSIONS: VISmax calculated during the first 24 h after postoperative intensive care unit admission in transplanted patients is independently associated with 1-year mortality. In addition, length of stay, duration of mechanical ventilation and infused inotropes increased with increasing VISmax.

Hemodynamic Evaluation of a Centrifugal Left Atrial Decompression Pump for Heart Failure with Preserved Ejection Fraction.

This article discusses a new continuous flow mini pump that has been developed to improve symptoms and prognosis in patients with Heart Failure with Preserved Ejection Fraction (HFpEF), for which there are currently no established treatments. The pump is designed to discharge a reduced percentage of blood volume from the left atrium to the subclavian artery, clamped at the bifurcation with the aortic arch. The overall specifications, design parameters, and hemodynamics of this new device are discussed, along with data from in vitro circulation loop tests and numerical simulations. The article also compares the results for two configurations of the pump with respect to key indicators of hemocompatibility used in blood pump development.

Association Between Shock Etiology and 5-Year Outcomes After Venoarterial Extracorporeal Membrane Oxygenation.

BACKGROUND: Outcomes of patients requiring venoarterial extracorporeal membrane oxygenation (VA-ECMO) vary greatly by etiology, but large studies that incorporate the spectrum of shock supported with ECMO are rare. OBJECTIVES: The purpose of this study was to describe the etiology-related outcome of patients with shock supported with peripheral VA-ECMO. METHODS: All consecutive adults with peripheral VA-ECMO between January 2015 and August 2018 at Pitié-Salpêtrière Hospital (Paris, France) were included in this retrospective observational study. The indication for VA-ECMO was cardiogenic shock. Rates of hospital death and neurological, renal, and pulmonary complications were evaluated according to etiology. RESULTS: Among 1,253 patients, hospital and 5-year survival rates were, respectively, 73.3% and 57.3% for primary graft failure, 58.6% and 54.0% for drug overdose, 53.2% and 45.3% for dilated cardiomyopathy, 51.6% and 50.0% for arrhythmic storm, 46.8% and 38.3% for massive pulmonary embolism, 44.4% and 42.4% for sepsis-induced cardiogenic shock, 37.9% and 32.9% for fulminant myocarditis, 37.3% and 31.5% for acute myocardial infarction, 34.6% and 33.3% for postcardiotomy excluding primary graft failure, 25.7% and 22.8% for other/unknown etiology, and 11.1% and 0.0% for refractory vasoplegia shock. Renal failure requiring hemodialysis developed in 50.0%, neurological complications in 16.0%, and hydrostatic pulmonary edema in 9.0%. CONCLUSIONS: Although the outcome differs depending on etiology, this difference is related more to the severity of the situation associated with the cause rather than the cause of the shock per se. Survival to 5 years varied by cause, which may reflect the natural course of the chronic disease and illustrates the need for long-term follow-up.

Clinical course of arrhythmogenic right ventricular cardiomyopathy with end-stage heart failure and outcome after heart transplantation.

BACKGROUND: Few data exist on the characteristics and outcomes of patients with arrhythmogenic right ventricular cardiomyopathy and advanced heart failure who undergo heart transplantation. AIM: To explore the pretransplant course and outcomes of patients with arrhythmogenic right ventricular cardiomyopathy after heart transplantation. METHODS: This observational retrospective monocentric study included all consecutive patients with arrhythmogenic right ventricular cardiomyopathy who underwent heart transplantation during a 13-year period (2006-2019) at Pitié-Salpêtrière University Hospital (Paris). RESULTS: A total of 23 patients with arrhythmogenic right ventricular cardiomyopathy underwent heart transplantation between 2006 and 2019. The median time from diagnosis to heart transplantation was 9 years, and the median age at transplantation was 50 years. At diagnosis, half of the patients had left ventricular dysfunction, 59% had extensive T-wave inversion and 43% had a history of sustained ventricular tachycardia. Only five patients were involved in intensive sport activity. Indications for heart transplantation were end-stage biventricular dysfunction in 13 patients, end-stage right ventricular heart failure in seven and electrical storm in three. Only three patients had pulmonary hypertension, and half of the patients had atrial arrhythmias. The survival rate 1 year after heart transplantation was 74% (95% confidence interval 53-88%). Eight patients experienced primary graft dysfunction needing extracorporeal membrane oxygenation. CONCLUSIONS: Patients with arrhythmogenic right ventricular cardiomyopathy who eventually needed heart transplantation mostly exhibited extended disease with biventricular dysfunction at diagnosis. Intensive sport activity did not seem to be a major determinant. Advanced heart failure usually occurred late in the course of the disease. Primary graft dysfunction after heart transplantation was frequent, and should be anticipated. Additional data are needed to identify the optimal timing for heart transplantation and predictors of end-stage heart failure in patients with arrhythmogenic right ventricular cardiomyopathy.

Impact of the 2018 French two-score allocation scheme on the profile of heart transplantation candidates and recipients: Insights from a high-volume centre.

BACKGROUND: In 2018, a new cardiac allograft allocation scheme, based on an individual scoring system, considering the risk of death both on the waiting list and after heart transplantation, was implemented in France. AIM: To assess the impact of this new scheme on the profile of transplantation candidates and recipients. METHODS: In this single-centre retrospective study, we included consecutive patients listed and/or transplanted between 01 January 2012 and 30 September 2021 at La Pitié-Salpêtrière Hospital. Baseline characteristics of patients were retrieved from the national CRISTAL registry and were compared according to the type of allocation scheme (before or after 2018). RESULTS: A total of 1098 newly listed transplantation candidates and 855 transplant recipients were included. One-year mortality rates after listing and after transplantation were 12.4% and 20%, respectively. At listing, the proportion of candidates on inotropes significantly declined following the scheme update (26.3 versus 20.9%; P=0.038), reflecting a change in medical practice. At transplantation, recipients had worse kidney function (estimated glomerular filtration rate<60mL/min/1.73 m2: old scheme, 29.7%; new scheme, 46.4%; P<0.001) and were more likely to be on extracorporeal membrane oxygenation support (33.5% versus 28.1%; P=0.080) under the new scheme, reflecting the prioritization of more severe patients. Outcomes after transplantation were not significantly influenced by the allocation system. CONCLUSIONS: The implementation of the 2018 French allocation scheme had a limited impact on the profile of transplantation candidates, but selected more severe patients for transplantation without significant impact on outcomes after transplantation.

Time course, factors related to, and prognostic impact of venoarterial extracorporeal membrane flow in cardiogenic shock.

AIMS: Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is currently one of the most used devices in refractory cardiogenic shock. However, there is a lack of evidence on how to set the 'optimal' flow. We aimed to describe the evolution of VA-ECMO flows in a cardiogenic shock population and determine the risk factors of 'high-ECMO flow'. METHODS AND RESULTS: A 7 year database of patients supported with VA-ECMO was used. Based on the median flow during the first 48 h of the VA-ECMO run, patients were classified as 'high-flow' or 'low-flow', respectively, when median ECMO flow was ≥3.6 or <3.6 L/min. Outcomes included rates of ventilator-associated pneumonia, ECMO-related complications, days on ECMO, days on mechanical ventilation, intensive care unit and hospitalization lengths of stay, and in-hospital and 60 day mortality. Risk factors of high-ECMO flow were assessed using univariate and multivariate cox regression. The study population included 209 patients on VA-ECMO, median age was 51 (40-59) years, and 78% were males. The most frequent aetiology leading to cardiogenic shock was end-stage dilated cardiomyopathy (57%), followed by acute myocardial infarction (23%) and fulminant myocarditis (17%). Among the 209 patients, 105 (50%) were classified as 'high-flow'. This group had a higher rate of ischaemic aetiology (16% vs. 30%, P = 0.023) and was sicker at admission, in terms of worse Simplified Acute Physiology Score II score [40 (26-58) vs. 56 (42-74), P < 0.001], higher lactate [3.6 (2.2-5.8) mmol/L vs. 5.2 (3-9.7) mmol/L, P < 0.001], and higher aspartate aminotransferase [97 (41-375) U/L vs. 309 (85-939) U/L, P < 0.001], among others. The 'low-flow' group had less ventilator-associated pneumonia (40% vs. 59%, P = 0.007) and less days on mechanical ventilation [4 (1.5-7.5) vs. 6 (3-12) days, P = 0.009]. No differences were found in lengths of stay or survival according to the ECMO flow. The multivariate analysis showed that risk factors independently associated with 'high-flow' were mechanical ventilation at cannulation [odds ratio (OR) 3.9, 95% confidence interval (CI) 2.1-7.1] and pre-ECMO lactate (OR 1.1, 95% CI 1.0-1.2). CONCLUSIONS: In patients with refractory cardiogenic shock supported with VA-ECMO, sicker patients had higher support since early phases, presenting thereafter higher rates of ventilator-associated pneumonia but similar survival compared with patients with lower flows.