Young South Asians With ST-Elevation Myocardial Infarction (STEMI) – Outcomes, Clinical and Angiographic Profiles.

Background : Why STEMI in young South Asians (SAs) has more adverse outcomes compared to elder population is underexplored. We conducted this study to learn about common risk factors, disease patterns and prognostic factors in this population. Methods: It was an observational study from 2013-2019 done at the Aga Khan University Hospital, Karachi, Pakistan, a tertiary care hospital. Patients aged < 45 years who presented with their first episode of ST elevated Myocardial Infarction (STEMI) and who underwent Primay PCI were included. Patients with previous MI or revascularization were excluded. Details of risk factors, lesion complexity and outcomes were noted. Main outcome measures were:i. Primary outcome of 30 day All-cause mortalityii. Secondary outcomes: (a) Composite of Shock/CPR/VT/Vfib, (b) Ejection fraction < 35%, (c) Delayed discharge > 5 days Results: Of a total of 1207 patients, only 165 patients (13%) were < 45 years old. Common risk factors included male gender 90.3%, n=149, obesity in 48.3%, n=69, history of tobacco in 45%, n=74 and positive family history in 48.4%, n=80. LAD was the culprit in 77.0%, n=127 with Single vessel disease (SVCAD) in 68%, n=112. Primary outcome of 30 day All-cause mortality was seen in 3.6%, n=6 patients. Secondary outcomes: (i) Composite of Shock/CPR/VT/Vfib was seen in 12%, n=20 associated to initial SBP < 110 mmhg (OR 4.1, 95% CI 1.2-13.4) or heart failure (OR 3.5, 95% CI 1.0-12.6). (ii) Ejection fraction <35% was seen in 29%. n=48 associated to anterior infarction (OR 5.0, 95% CI 1.8-13.5 ), Time to hospital (TTH) > 4 hours (OR 2.6, 95% CI 1.0-6.7) and heart failure (OR 5.1, 95% CI 1.7-15.4). (iii) Delayed discharge > 5 days was seen in 27.3%, n=45 associated to TTH > 4 hours (OR 3.8, 95% CI 1.3-11.2), the Composite of Shock/CPR/VT/VF (OR 6.4, 95% CI 1.9-21.6) and HTN (OR 2.1, 95% CI 1.0-5.2). Conclusion: Young SAs with STEMI are usually obese, tobacco-users with positive family history. LAD is the most common culprit vessel. Anterior STEMI, delayed presentation, initial SBP, and heart failure may help stratify these patients.