Abstract 17497: Intracoronary Enalaprilat to Reduce Microvascular Damage Occurring During Elective Percutaneous Coronary Intervention Trial (promicro Trial): A Randomized Double-Blind Controlled Study
Aims. Angiotensin converting enzyme (ACE)- inhibitors improve coronary flow and reduce ischemic events during percutaneous coronary intervention (PCI). However, the mechanisms leading to this protective effect are unknown. We aimed at assessing in patients with stable angina undergoing PCI, whether pre-treatment with intracoronary enalaprilat: (1) improves microvascular function, as measured by the index of microvascular resistance (IMR); (2) reduces the risk of peri-procedural myocardial necrosis.
Methods and results. Forty patients were randomized to receive an intracoronary infusion of enalaprilat (50 µg) or placebo before PCI. IMR was measured in the index coronary artery at baseline, 10 minutes after enalaprilat infusion and post-PCI. High sensitive troponin (hs-Tn) was measured at baseline and 24 hours after the procedure. Enalaprilat infusion was associated with a significant reduction of IMR (27.0±11.4 at baseline vs. 19.3±8.7 post-infusion; p<0.0001). IMR did not change after placebo (26.0 ±14.8 vs. 25.5±14.9 post-infusion; p=0.744). Post-PCI IMR was significantly lower in the enalaprilat group as compared with the placebo group (15.0±8.1 vs. 31.6±20.8; p=0.002). In the overall population, IMR post-PCI significantly correlated with post-procedural hs-Tn levels (r=0.611, p<0.0001). In addition, post-procedural hs-Tn increase was significantly lower in patients pre-treated with enalaprilat as compared with control patients (9.9 [2.7-19.0] ng/ml vs. 26.6 [6.3-60.5] ng/ml; p=0.035).
Conclusions. In patients with stable angina undergoing PCI, intracoronary infusion of enalaprilat improves microvascular function and protects from the occurrence of myocardial necrosis.
- © 2012 by American Heart Association, Inc.