Long-term Outcome of the Randomized Defibrillator After Primary Angioplasty (DAPA) Trial.

Background - The randomized Defibrillator After Primary Angioplasty (DAPA) trial aimed to evaluate the survival benefit of prophylactic implantable cardioverter defibrillator (ICD) implantation in early selected high-risk patients after primary percutaneous coronary intervention (PCI) for ST elevation myocardial infarction (STEMI). Methods - A randomized, multicenter, controlled trial compared ICD versus conventional medical therapy in high risk primary PCI patients, based on one of the following factors: left ventricular ejection fraction (LVEF) < 30% within 4 days after STEMI, primary ventricular fibrillation, Killip class ≥2 and/or TIMI flow < 3 after PCI. ICD was implanted 30-60 days after MI. Primary endpoint was all-cause mortality at 3 years follow-up. The trial prematurely ended after inclusion of 266 patients (38% of the calculated sample size). Additional survival assessment was performed in February 2019 for the primary endpoint. Results - A total of 266 patients, 78.2% males, with a mean age of 60.8 ± 11.3 years, were enrolled. 131 patients were randomized to the ICD arm and 135 patients to the control arm. All-cause mortality was significant lower in the ICD group (5% vs 13%, HR 0.37; 95% CI 0.15-0.95) after 3 years follow-up. Appropriate ICD therapy occurred in 9 patients at 3 years follow-up (5 within the first 8 months after implantation). After median long-term follow-up of 9 years (IQR, 3-11), total mortality (18% vs 38%, HR 0.58; 95% CI 0.37-0.91) and cardiac mortality (HR 0.52; 95% CI 0.28-0.99) was significant lower in the ICD group. Non-cardiac death was not significantly different between groups. LVEF increased ≥10% in 46.5% of the patients during follow up and the extent of improvement was similar in both study groups. Conclusions - In this prematurely terminated and thus underpowered randomized trial, early prophylactic ICD implantation demonstrated lower total and cardiac mortality in high-risk STEMI patients treated with primary PCI.