Sub-acute cardiac magnetic resonance to predict irreversible reduction in left ventricular ejection fraction after...

Area of Science:

• Cardiology
• Medical Imaging
• Biomedical Engineering

Background:

• ST-segment elevation myocardial infarction (STEMI) can lead to irreversible reduction in left ventricular ejection fraction (LVEF).
• Reduced LVEF is a significant prognostic factor post-STEMI, often requiring medical therapy and prophylactic implantable cardioverter-defibrillator (ICD) implantation.

Purpose of the Study:

• To predict irreversible reduction in LVEF after STEMI using cardiac magnetic resonance (CMR) alongside clinical parameters.
• To identify patients who may benefit from early intervention and prophylactic ICD implantation.

Main Methods:

• A post-hoc analysis of the DANAMI-3 trial program involving 649 patients who underwent CMR during hospitalization.
• Patients were categorized into two groups based on CMR-LVEF at 3 months: LVEF ≤35% (Group 1) and LVEF >35% (Group 2).
• Multivariate analysis identified predictors of LVEF ≤35%, including Killip class, symptom onset-to-wire time, index echocardiography LVEF, and infarct size on index CMR.

Main Results:

• Only 2.3% of patients (15/649) had LVEF ≤35% at 3 months.
• Independent predictors of LVEF ≤35% included Killip class >1 (OR 7.39), symptom onset-to-wire ≥6h (OR 7.19), index echocardiography LVEF ≤35% (OR 7.11), and index CMR infarct size ≥40% (OR 42.62).
• Clinical models incorporating these parameters achieved 100% positive predictive value in identifying patients with final LVEF ≤35%.

Conclusions:

• Late Gadolinium enhancement assessed by CMR during hospitalization is a strong predictor of irreversible LVEF reduction post-STEMI.
• This assessment, combined with clinical data, can aid in selecting high-risk STEMI patients for interventions like prophylactic ICD implantation.
• Further research is needed to validate these findings for clinical application.