Angiotensin-converting-enzyme inhibitors in hemodynamic congestion: a meta-analysis of early studies

Aim Major clinical trials have shown that angiotensin-converting enzyme (ACE) inhibitors reduce mortality and morbidity in congestive heart failure (HF). Prior to these seminal findings hemodynamic effects of ACE inhibitors were examined in small studies. We aimed to review these studies systematically and meta-analyze the effects of ACE inhibitors on hemodynamics in HF. Methods and results We identified studies investigating the acute hemodynamic effect of ACE inhibitors in naive patients with congestive heart failure by searching PubMed and the Cochrane Central Register of Controlled Trials. We extracted the changes in hemodynamic measures and their standard errors from study reports or calculated these values from baseline and post-medication measurements. Data were pooled using random effects models. In total, 41 studies with 46 independent cohorts consisting of 676 patients were included. ACE inhibitor treatment reduced pulmonary capillary wedge pressure by 7.3 (95% confidence interval 6.4-8.2) mmHg and right atrial pressure by 3.7 (95% confidence interval 1.3-6.1) mmHg in patients with HF. Cardiac index increased by 0.4 (95% confidence interval 0.2-0.6) ml/min/m(2). Changes in hemodynamic measures were strongly connected to each other in weighted simple linear regression models. Conclusion Angiotensin-converting enzyme-inhibitors acutely reduced cardiac filling pressures and increased cardiac output in patients with congestive heart failure who were naive for these drugs. These data indicate that ACE inhibitors exhibit a strong decongesting effect in congestive heart failure. In light of their impact on long-term prognosis, ACE inhibitors should also be considered as decongesting drugs in stable patients.