Transplantation of progenitor cells and regeneration enhancement in acute myocardial infarction (TOPCARE-AMI): final 5-year results suggest long-term safety and efficacy

Abstract

Background: Limited data is available for investigating the long-term safety and effects of intracoronary progenitor cell therapy in patients with acute myocardial infarction (AMI).

Objective: To assess the clinical course, NT-proBNP and MRI data as objective markers of cardiac function of the TOPCARE-AMI patients at 5-year follow-up.

Design: The TOPCARE-AMI trial was the first randomized study investigating the effects of intracoronary infusion of circulating (CPC) or bone marrow-derived progenitor cells (BMC) in 59 patients with successfully reperfused AMI.

Results: Five-year follow-up data were completed in 55 patients, 3 patients were lost to follow-up. None of the patients showed any signs of intramyocardial calcification or tumors at 5 years. One patient died during the initial hospitalization, no patient was rehospitalized for heart failure and 16 patients underwent target vessel revascularization (TVR). Only two TVRs occurred later than 1 year after cell administration making it very unlikely that the infused cells accelerate atherosclerotic disease progression. Serum levels of NT-proBNP remained significantly reduced at the 5-year follow-up indicating the absence of heart failure. MRI subgroup analysis in 31 patients documented a persistent improvement of LV ejection fraction (from 46 ± 10% at baseline to 57 ± 10% at 5 years, p < 0.001)). Simultaneously, there was a reduction (p < 0.001) in functional infarct size measured as late enhancement volume normalized to LV mass. However, whereas LV end-systolic volume remained stable, LV end-diastolic volume increased significantly.

Conclusions: The 5-year follow-up of the TOPCARE-AMI trial provides reassurance with respect to the long-term safety of intracoronary cell therapy and suggests favorable effects on LV function.