Integrated left ventricular geometry-function phenotypes and long-term outcomes after acute myocardial infarction.

BACKGROUND/AIMS: Left ventricular (LV) remodeling after acute myocardial infarction (AMI) is a key determinant of long-term outcomes. However, it remains unclear how LV geometry and systolic function interact to influence prognosis in real-world populations. We investigated the combined prognostic impact of LV dilatation and systolic dysfunction in patients with AMI.

METHODS

We analyzed 19,664 patients with AMI from nationwide Korean multicenter registries. LV geometry-function phenotypes were defined according to LV end-diastolic dimension (LVEDD ≥53 mm for dilatation) and LV ejection fraction (LVEF ≤50% for reduced systolic function), and categorized as non-dilated/preserved (group A), dilated/preserved (group B), non-dilated/reduced (group C), and dilated/reduced (group D). The primary endpoint was 3-year major adverse cardiac and cerebrovascular events (MACCE), defined as cardiac death, non-fatal myocardial infarction, unplanned revascularization, cerebrovascular accident, and cardiovascular readmission. Associations between baseline geometry-function phenotypes and outcomes were assessed using multivariable Cox proportional hazards models.

RESULTS

The incidence of MACCE increased stepwise from group A to D (13.2%, 13.5%, 16.8%, and 21.9%, respectively). In fully adjusted analyses, LV dilatation was not associated with increased risk in patients with preserved LVEF [group B vs. group A: hazard ratio (HR), 1.13; 95% confidence interval, 0.99-1.29]. In contrast, LV dilatation was associated with a higher risk when accompanied by reduced LVEF [group C: HR, 1.12 (1.01-1.24); group D: HR, 1.44 (1.29-1.60)].

CONCLUSIONS

The prognostic significance of LV dilatation after AMI depends on underlying systolic function. While LV dilatation alone may reflect a compensatory process in preserved LVEF, its presence in reduced LVEF identifies a high-risk phenotype. An integrated assessment of LV geometry and function may provide complementary risk stratification beyond conventional LVEF-based assessment.