Smoking cessation after ST-elevation myocardial infarction (STEMI) was associated with differences in infarct evolution and clinical outcomes. A prospective study, published in the European Heart Journal Cardiovascular Imaging, assessed infarct dynamics in 672 revascularized patients with first-time STEMI, with smoking behavior documented at baseline and after four months.

Cardiac magnetic resonance (CMR) imaging was performed at baseline, four months, and twelve months to evaluate infarct characteristics. Major adverse cardiac events (MACE), defined as all-cause death and re-infarction, were assessed over a median observation period of 3.4 years.

At baseline, 382 patients (57%) were active smokers, and 183 (48%) discontinued smoking after the infarction. Initial infarct size did not differ between groups. At follow-up CMR, infarct size reduction was greater in patients who quit smoking compared with those who continued smoking (after twelve months: 62% vs. 47%, p<0.001).

MACE occurred less frequently in patients who quit smoking (4% vs. 12%, p=0.005). Multivariable logistic regression showed that continued smoking was associated with reduced infarct healing. Multivariable Cox regression identified continued smoking as a marker for MACE, independent of traditional cardiovascular risk factors.

These findings indicate that smoking cessation after STEMI was associated with greater infarct size reduction and lower rates of adverse events during follow-up.