Clinical Benefit of Chelation Therapy in Post-MI Patients With Diabetes and Peripheral Artery Disease

Introduction: The NIH-funded Trial to Assess Chelation Therapy (TACT) reported a clinical benefit of ethylene diamine tetraacetic acid (EDTA)-based chelation on cardiovascular (CV) outcomes in post-MI patients with diabetes (DM). Post-MI diabetic patients with peripheral artery disease (PAD) have particularly high risk. Methods: TACT, a multi-center, double-blind, placebo-controlled, trial of EDTA chelation, enrolled patients (pts) age > 50 years with an MI at least 6 weeks prior and creatinine Results: TACT enrolled 1708 pts, of which 303 (18%) had PAD. EDTA chelation reduced the primary endpoint by a similar extent in pts with (hazard ratio (HR) 0.7) and without PAD (HR 0.87, p for interaction 0.38). Among the 633 (37%) of patients with DM, 153 (24%) had PAD. There were 81 assigned to EDTA and 72 to placebo. Baseline characteristics including obesity, hypertension, hypercholesterolemia, heart failure, stroke and prior CABG were similar between treatment groups. Creatinine was higher in the placebo group (median 1.2 v 1.0; p=0.003). There were 80% on statins, 92% on antiplatelet or antithrombotic therapy, and 32% treated with insulin. EDTA chelation led to a reduction in the primary endpoint (46% vs. 22%; p=0.002, Figure), and total mortality (25% v. 11%, p=0.032). HR point estimates comparing chelation vs. placebo for each component of the composite endpoint were all Conclusions: In post-MI pts with DM and PAD treated with standard therapies, EDTA-based chelation therapy markedly reduced cardiovascular events.