TEMPORARY MECHANICAL CIRCULATORY SUPPORT IN CARDIOGENIC SHOCK: ANALYSIS OF SURVIVAL RATES

Background and Aims: Cardiogenic shock (CS) mortality remains high, ranging from 30 to 60% in-hospital and from 40 to 60% at 1 year. The aim of the present study is to determine the survival (at 30 days and 1 year) and the predictors of 30-day mortality in a cohort of patients treated with temporary mechanical circulatory support (MCS) devices for CS. Methods: Retrospective observational study including adult patients treated with temporary MCS devices for CS in a tertiary level cardiothoracic centre between August 2015 and August 2021. Patients were classified according to the aetiology of CS and the type of temporary MCS. The severity of CS (quantified using the SCAI shock stages) was assessed at the hospital admission, at the time of temporary MCS implantation, and after 24 hours of MCS. Clinical data, haemodynamic and respiratory parameters, biochemical markers, and dosage of vasopressors and inotropes were collected. Kaplan-Meier survival analysis was performed and logistic regression was applied to identify predictors of 30-day mortality. Results: Three hundred twelve patients (age 56.5 ± 16.9 years old, 68.9% males) treated with temporary MCS for CS were analysed. Aetiologies of CS were: postcardiotomy in 43.3%, acute myocardial infarction in 23.1%, acute decompensated heart failure in 10.9%, acute myocarditis in 7.1%, extracorporeal cardiopulmonary resuscitation in 4.2%, ventricular arrhythmias in 1.9%, acute pulmonary embolism in 1.9%, and septic cardiomyopathy in 1.6%. The temporary MCS devices were implanted at SCAI shock stage B in 7.1% patients, C in 24.4%, D in 53.8%, and E in 14.7%. The temporary MCS devices used were: intra-aortic balloon pump (IABP) in 62.2%, veno-arterial extracorporeal membrane oxygenation (V-A ECMO) in 29.2%, Impella in 4.5%, right ventricular assist device (RVAD) in 3.2%, and biventricular assist device (BiVAD) in 1.0%. Thirty-five patients (11.2%) required escalation of temporary MCS device; the escalation rate was significantly higher in nonsurvivors compared to survivors at 30 days. At the time of temporary MCS insertion, 30-day survivors had compared to survivors: higher diastolic blood pressure (DBP) and mean arterial pressure (MAP), lower central venous pressure, lower prevalence of significant right ventricular systolic dysfunction, lower vasoactive-inotropic score (VIS), and lower serum creatinine. Arterial blood gas parameters were significantly worse in 30-day nonsurvivors compared to survivors: lower pH, higher lactate, lower base excess, and lower P/F ratio. After 24 hours of temporary MCS, survivors at 30 days were characterized by: higher MAP and DBP, lower lactate, higher prevalence of lactate clearance, and lower VIS. Two hundred eighty-eight patients (92.3%) received invasive mechanical ventilation. Seventy-three patients (23.4%) required acute renal replacement therapy (RRT); the use of continuous RRT was significantly higher in 30-day nonsurvivors compared to survivors. Two hundred nineteen patients (70.2%) were weaned from temporary MCS. Survival rates were: 65.1% at 30 days, 61.5% at ICU discharge, 55.3% at hospital discharge, and 52.4% at 1 year. In the multiple logistic regression model considering variables at the time of temporary MCS insertion, lactate level and serum creatinine were associated with 30-day mortality. Conclusions: Survival rate at 30 days and 1 year were in line with the currently reported outcomes. Lactate levels before implantation of temporary MCS device and lactate clearance after 24 hours of MCS were predictors of 30-day mortality. Use of continuous renal replacement therapy and limb ischaemia, as complication of MCS devices, were associated with 30-day mortality.