Abstract 16264: Ace-inhibitors and Vasoplegia in the Post Cabg Population/valvular Surgery Population: An Updated Systematic Review and Meta-analysis

Abstract

Introduction: Chronic use of ACE-i has been presented as a risk factor of post operative vasoplegia after cardiac surgery. However, a recent meta analysis of studies in the general cardiac surgery population identified renal failure as the only pre-operative risk factor for vasoplegia. We sought to systematically review the relationship of chronic ACE-i and vasoplegia in patients undergoing CABG /valve surgery. Hypothesis: Studies on vasoplegia after CABG / valve surgery were extracted by a research librarian (registered review CRD42017072923) before bias and quality of studies were assessed. We adjudicated vasoplegia as MAP < 60 mmHg and use of at least one non dopaminergic vasoactive drug up to 4 hours post operatively. Otherwise, studies reported vasoplegia as MAP < 60 mmHg, CI > 2.5 l/min/m2 and SVR < 600 dynes/sec/cm2 in the CSICU. We pooled the incidence of vasoplegia then completed a meta-analysis with random effect model using RevMan and Stata. Methods: Of the 2337 articles obtained (1940 non relevant, 22 reviews, 5 duplicates and 5 editorials), we pre-selected 365 abstracts and summarized data from 8,818 patients out of 7 articles selected after full text review. Results: All but one study looked at patients with LVEF > 40%. The pooled incidence of vasoplegia was 11.2% (95% CI 4.7-28.2). The OR of vasoplegia in patients on chronic ACE-i was 1.74 (95% CI: 1.47-2.06). We could not investigate the importance of pre-existing renal failure on the risk of post operative vasoplegia in patients on ACE-i. Accounting for substantial heterogeneity, the Egger test was in favour of small-study effects due to the number of cases of vasoplegia and the size of the cohorts studied (p=0.073). Conclusions: The risk of vasoplegia seems to be higher in patients on ACE-i undergoing CABG/valve surgery in this population. Two RCT's (161 patients) did not prove the benefit of temporary discontinuation of RAS blockade on the incidence of distributive shock during the first days after surgery. Because ACE-i are frequently prescribed in patients awaiting CABG, our work calls for larger and more elaborated studies to reduce the risk of vasoplegia.