Rapid improvement of carotid plaque echogenicity within 1 month of pioglitazone treatment in patients with acute coronary syndrome

ObjectiveThis study examined whether pioglitazone, an agonist of peroxisome proliferator-activated receptor γ, may stabilize vulnerable plaque with use of ultrasound evaluation of carotid artery plaque echolucency in patients with acute coronary syndrome (ACS) and type 2 diabetes mellitus (DM).Methods and resultsTreatment with pioglitazone (15 or 30 mg/day, n = 31) or placebo (n = 30) was randomly assigned and initiated within 5 days after the onset of ACS in 61 patients with type 2 DM and echolucent carotid plaques. Vulnerable carotid plaques were assessed by measuring plaque echolucency using carotid ultrasound with integrated backscatter (IBS) before, at 2 weeks, and 1 month and 6 months after initiation of treatment. An increase in IBS value reflects an increase in carotid plaque echogenicity. Calibrated IBS value (intima-media IBS value minus adventitia IBS value) of echolucent carotid plaques did not change at 2 weeks but was significantly increased at 1 month after treatment in the pioglitazone group but not in the placebo group. The increase in calibrated IBS value was not significantly correlated with the effect of pioglitazone on glycemia.ConclusionsPioglitazone rapidly improved carotid plaque echolucency within 1 month of therapy initiation in patients with ACS and type 2 DM.