Cardiac remodeling in acute myocardial infarction: Prospective insights from multimodality ultrasound imaging

The severity of MI declined markedly in the last decade, and contemporary patterns of cardiac remodeling after MI are not defined.

We prospectively enrolled community patients with first MI and performed comprehensive two- and three-dimensional echocardiography. Remodeling was defined as left ventricular (LV) end-systolic volume index (ESVI) above American Society of Echocardiography normal values. Remodeling patterns were characterized as an increase in LVESVI or LV end-diastolic volume index (LVEDVI), or both.

Between 2014 and 2016, 213 patients (63±13 years; 34% women) were enrolled within 3 days after MI (77% non-ST-elevation MI). Acute remodeling was present in 51% of patients. Higher troponin and wall motion score index were associated with greater remodeling (p < 0.001). Atrial annular area, leaflet tenting and papillary muscle areas increased with greater remodeling (p < 0.001). The greater the cardiac remodeling, the lower the LV ejection fraction and global longitudinal strain (p < 0.001). This decrease in LV function was accompanied by stroke volume augmentation and maintenance of cardiac index at the expense of increased LVEDVI. Different remodeling patterns were identified. Cases showing increased LVEDVI and normal LVESVI had smallest infarct size and better hemodynamics compared to cases with augmented LVESVI and normal LVEDVI.

Acute remodeling occurs in more than half of first MI cases and exhibits different patterns defined by cavity size and hemodynamic profile. Acute remodeling is a global phenomenon, which also involves the left atrium and the mitral apparatus.