Influence of time to treatment and other risk factors on infarct size and transmurality in the case of ST-elevated myocardial infarction managed by primary angioplasty and assessed by delayed enhancement magnetic resonance imaging

Objectives: To evaluate the association between time to treatment and to check the effect of various risk factors such as diabetes mellitus, hypertension (HTN), smoking, family history of coronary artery disease (CAD) and obesity on infarct size (IS), transmurality and ST-segment resolution (STR) with DE-MRI (delayed enhancement magnetic resonance imaging) on 3-month follow-up in patients treated for ST-elevated myocardial infarction (STEMI), with primary percutaneous coronary intervention (PPCI). Background: Early PPCI decreases IS and transmurality but increases STR. Materials and Methods: Fifty consecutive patients with STEMI treated with reperfusion therapy in the form of PPCI and underwent cardiac MRI at 3-month interval follow-up. The primary endpoint is final IS and transmurality as assessed by DE-MRI at 3-month follow-up. Results: IS and transmurality increase and STR decreases with increase in duration to percutaneous coronary intervention from the onset of symptoms. Similarly, the effect of various confounding factors such as diabetes mellitus, HTN, smoking, family history of CAD and obesity on IS, transmurality and STR was assessed which did not affect immediate prognosis during treatment. Conclusion: Primary angioplasty is the treatment modality of choice in the case of STEMI when available. Time to treatment directly influences STR, final IS and transmurality, that is, the earlier the intervention done, more will be STR and lesser will be final IS and transmurality. There is no significant effect of confounding variables such as cardiac risk factors except family history of CAD on immediate prognosis during treatment.