Timing of Empagliflozin in Primary PCI: Pre-Reperfusion Versus Post-Reperfusion Versus Placebo in South Asian STEMI Patients

The goal of this clinical trial is to learn if giving the drug empagliflozin before versus after a heart procedure called primary PCI (percutaneous coronary intervention) affects how much heart muscle is damaged during a heart attack. Primary PCI is a procedure that opens blocked heart arteries using a small balloon and stent. While this procedure saves lives, it can also cause extra injury to the heart muscle when blood flow returns. Researchers want to know if empagliflozin given before the procedure can protect the heart better than giving it after the procedure. The main questions this trial aims to answer are: Does giving empagliflozin before the PCI procedure reduce heart muscle injury more than a placebo (a look-alike pill with no active drug)? Does giving empagliflozin before PCI protect the heart better than giving it after PCI? Does empagliflozin given after PCI reduce heart muscle injury compared with a placebo? Researchers will compare three groups of participants to see if the timing of empagliflozin matters: Group A receives empagliflozin before the PCI procedure Group B receives empagliflozin after the PCI procedure Group C receives a placebo at both times All three groups will continue taking their assigned study pills for 90 days. Participants in this study are adults aged 18 to 75 from South Asian backgrounds (Pakistani, Indian, Bangladeshi, Sri Lankan, or Nepali) who are having their first heart attack and are scheduled for the PCI procedure within 12 hours of their symptoms starting. Participants will: Take a single loading dose of the study pill or placebo right before the PCI procedure Take a single loading dose of the study pill or placebo within 2 hours after the PCI procedure Continue taking the study pill or placebo once daily for 90 days Have blood samples taken 6 times over 48 hours to measure heart muscle injury Have heart function tests at Day 3, Day 30, and Day 90 (echocardiograms, which are ultrasound pictures of the heart) Have a special heart scan (CMR) between Day 3 and Day 5 for some participants to get detailed pictures of the heart muscle Complete 90 days of follow-up with clinic visits and tests Researchers will measure heart muscle injury using a blood test called high-sensitivity troponin. This test measures a protein that is released when heart muscle is damaged. The total amount of this protein released over 48 hours will tell researchers how much heart muscle was injured.

Inclusion Criteria: * Age 18-75 years at presentation. * South Asian ethnicity (Pakistani, Indian, Bangladeshi, Sri Lankan, or Nepali origin). * First STEMI: ST-elevation ≥1 mm in ≥2 contiguous limb leads, or ≥2 mm in ≥2 contiguous precordial leads, or new LBBB with consistent presentation. * Symptom onset to hospital arrival ≤12 hours. * Scheduled for primary PCI with intent to perform balloon inflation and stenting. * eGFR ≥45 mL/min/1.73m² (CKD-EPI) from point-of-care creatinine at presentation. * Able to take oral medication (or crushed tablet with water), swallowing ability confirmed by treating nurse. * Written informed consent from patient or legally authorised representative Exclusion Criteria: * Cardiogenic shock at presentation (Killip IV: SBP \