DCB vs. DES in Young STEMI Patients: The DCB-STEMI Trial

Background: ST Elevation Myocardial Infarction (STEMI) in young adults (\<50 yrs) carries high Percutaneous coronary intervention (PCI) risks. While drug-eluting stents (DES) reduce restenosis versus angioplasty, they increase risks of in-stent restenosis, thrombosis, prolonged dual antiplatelet therapy (DAPT), and endothelial dysfunction. Drug-coated balloons (DCB) provide a "leave nothing behind" strategy, potentially mitigating these issues. Evidence, including a JACC CVI report, suggests DCB outcomes comparable to DES in STEMI. South Asia faces a heavy burden. The national Institute of Cardiovascular diseases (NICVD), Karachi performed 17,761 primary PCIs in 2022, with 45% in patients \<50 yrs. Study Design: This single-center Randomized Controlled Trial (RCT) compares paclitaxel-coated DCB (3.0 µg/mm², 30s inflation) vs. Drug eluting stents (DES) in young STEMI patients (\<50 yrs) undergoing primary PCI. The primary endpoint is 1-year vessel oriented cardiac events (VOCE)= Cardiovascular /all-cause death, target vessel MI, or Target lesion revascularization (TLR). Secondary endpoints include vessel-oriented CV events, bleeding, TIMI III flow, residual stenosis, abrupt closure, and bailout stenting. An intravascular ultrasound (IVUS) substudy (100 DCB pts) will evaluate remodeling and late lumen loss (LLL) at 6 months. Methods: 496 patients (248/arm) will be randomized 1:1, powered for non-inferiority (margin 4.5%) assuming VOCE 8.5% (DES) vs. 6.25% (DCB), 80% power, and 5% dropout. Inclusion: age 18-50, STEMI. Exclusion: End stage renal disease (ESRD), severe multivessel disease, complex lesions, or high thrombus burden. All will receive ticagrelor 90 mg BID for 1 month. A pilot of 50 pts will first assess safety (abrupt closure, lesion prep). Analysis: Intention-to-treat (ITT) will be primary; modified ITT for secondary endpoints. Statistics include chi-square/Fisher for categorical, t-test/Wilcoxon for continuous, and Kaplan-Meier/Cox for survival. Oversight by data safety monitoring board (DSMB) and Events adjudication Committee (EAC). Significance: This trial leverages NICVD's high PCI volume to test DCB as an alternative to DES in young STEMI patients. By avoiding permanent implants, DCB may reduce long-term complications and DAPT needs. The IVUS substudy and pilot phase strengthen rigor. If non-inferiority is proven, DCB could reshape STEMI management in South Asia and similar high-burden regions.