Age-Related Vascular Stiffness and Left Ventricular Size After Myocardial Infarction

Aortic stiffness increases with age and may contribute to adverse remodeling after myocardial infarction (MI). The authors examined whether vascular stiffness affects left ventricular (LV) size after MI using contrast-enhanced cardiac magnetic resonance imaging. Despite similar infarct sizes, patients aged 60 years or older (n=30) had a lower ejection fraction (42±15 vs 53±11%, P<.01) and greater end-systolic volume index (75±47 vs 44±18 mL/m², P<.01) than younger patients (n=19). As infarct size increased, LV end-systolic volumes (P<.0001) and ejection fraction (P<.0001) in the older participants were progressively greater. Participants with greater aortic stiffness had greater end-systolic volume indices (P<.0001) and lower ejection fraction (P<.0001) with increasing infarct size. Using multivariate analysis, MI size (P<.001) and aortic distensibility (P=.02) were significant predictors of end-systolic volume index. Older patients have increased LV size after MI compared with younger patients, possibly related to age-related decreases in aortic distensibility affecting LV remodeling.