Early administration of intracoronary verapamil improves myocardial perfusion during percutaneous coronary interventions for acute myocardial infarction

Background: Intracoronary calcium-channel blockers administered in the event of no reflow during percutanous coronary intervention (PCI) in acute myocardial infarction (AMI) have been shown to improve myocardial perfusion. Study objective: To evaluate the effects of the administration of intracoronary verapamil before the occurrence of no reflow during direct PCI. Design and setting: Single-center, nonrandomized, prospective study with a retrospective control group. Patients; and methods: From September 2001 to December 2003, 50 consecutive patients with AMI were prospectively enrolled for intracoronary verapamil treatment. Intracoronary verapamil was administered immediately prior to balloon inflation and at short intervals dining the procedure thereafter. Retrospectively, 50 consecutive AMI patients who had undergone direct PCI and had not received intracoronary calcium-channel blockers were enrolled as control subjects. Patients with cardiogenic shock or platelet glycoprotein IIb/IIIa inhibitor were excluded. Thrombolysis in Myocardial infarction (TIMI) flow grade, corrected TIMI frame count (CTFC), and TIMI myocardial perfusion grade (TMPG) were assessed prior to and following PCI by two independent cardiologists blinded to the procedures. Results: The two groups had similar baseline and postprocedural angiographic characteristics, although the patients who been administered verapamil received more stent implantations than the control subjects (84% vs 60%, p = 0.008). Postprocedural TIMI flow < 3 (odds ratio [OR], 0.39; 95% confidence interval [CI], 0.12 to 1.30; p = 0.18) and TMPG (OR, 1.24; 95% CI, 0.46 to 3.34; p = 0.68) were not associated with the implantation of the stents. There were no significant difference in post-PCI TIMI flow (p = 0.68) and CTFC (p = 0.36) between patients treated with verapamil and the Control subjects. Post-PCI TMPG was significantly better in patients treated with intracoronary verapamil (p = 0.003). Forty-two percent of the patients treated with verapamil were found to have TMPG-3,while only 14% of the control subjects were found to have the same degree of TMPG (p = 0.004). Treatment with intracoronary verapamil (OR, 0.26; 95% CI, 0.12 to 0.58; p = 0.001) and pre-PCI TIMI flow (OR, 0.54; 95% CI, 0.35 to 0.84; p = 0.006) were found by multiple logistic regression to be independent predictors of TMPG. Conclusions: Early administration of intracoronary verapamil during direct PCI improves postprocedural myocardial perfusion, as evaluated by TMPG.