Unresolved issues in left ventricular postischemic remodeling and progression to heart failure.

ABSTRACT

In the past decades, myocardial infarction periacute mortality markedly declined since coronary reperfusion therapy has been adopted. Despite immediate benefits of coronary blood flow restoration, the percentage of new onset heart failure has increased over time suggesting that ischemia can run detrimental consequences beyond the immediate anoxic hit. By accepting to aggregate all types of heart failure regardless of underlying cause, the current practice did not help to shed light on the complex postischemic cardiac biology indicating that heart failure is somewhat unavoidable. In the ischemic sequel, the activated mechanisms aim to repair the infarcted zone and to compensate for the lost myocyte functions, thus allowing the heart to maintain the efficient cardiac output for vital organs. The variety of underlying preexisting conditions, as well as the multifaceted components of cardiac molecular structure, cellular state, and electrophysiological postischemic events pave the way for long-term adverse cardiac remodeling. We focused our attention on multiple factors, which include myocyte loss, hypertrophy, hyperplasia, extracellular matrix changes linked to myocardial fibrosis and scar, metabolic imbalance, as well as immunologic response occurring in the acute myocardial aftermath. Moreover, we reported both current pharmacological strategies and future perspectives that might be useful in clinical practice. Furthermore, we discussed the cardiac magnetic resonance as the most promising noninvasive imaging tool, which could be helpful in identifying the amount of myocardial damage. Despite the redundancy of molecular pathogenic mechanisms making it impossible to estimate the proportionate contributions in generating the heart failure phenotype, a deeper understanding will contribute to more customized patient management.