Abstract

Objectives: To examine the safety and efficacy of pioglitazone in patients with ST-elevation myocardial infarction (STEMI) treated with primary bare metal stent (BMS) implantation.

Background: While recent studies have shown that thiazolidinediones reduce neointimal hyperplasia after BMS implantation, this drug classification sometimes cause fluid retention that may lead to heart failure.

Methods: Diabetic or non-diabetic patients with STEMI (<12 hrs from onset) successfully treated with primary BMS implantation were randomized to either the pioglitazone (15mg, up to 30mg) or control groups. Patients in cardiogenic shock were excluded. Primary efficacy endpoint was percent neointimal volume within the stented segment at 6 months using 3D intravascular ultrasound. Safety endpoint was a composite of all-cause mortality, re-infarction, or heart failure requiring hospitalization.

Results: Between October 2005 and July 2007, 96 patients were randomized into the pioglitazone (N=48) or control group (N=48). At follow-up, percent neointimal volume and neointimal volume index were significantly reduced in the pioglitazone group (22±13 vs. 28±13 %, P=0.04; 1.5±0.9 vs. 2.0±0.8 mm3/mm, P=0.02). During 6 months, 2 control patients died, 4 patients (1 in pioglitazone group, 3 in control) suffered from stent thrombosis resulting in re-infarction, and 3 patients (2 in pioglitazone group, 1 in control) had heart failure, resulting in similar incidence of safety endpoint (3 vs. 6).

Conclusions: Treatment of pioglitazone reduced neointimal hyperplasia in STEMI patients treated with primary stent implantation without placing the patient at increased risk of complications. Additional larger trials will be necessary to establish the clinical benefit of pioglitazone.