The Role for Cardiovascular Remodeling in Cardiovascular Outcomes

Ischemic and non-ischemic injury to the heart causes deleterious changes in ventricular size, shape, and function. This adverse remodeling is mediated by neurohormonal and hemodynamic alterations and is reflected in non-invasive measures of left ventricular ejection fraction (LVEF), left ventricular end-systolic volume (LVESV), and left ventricular end-diastolic volume (LVEDV). These measures are closely linked to cardiovascular outcomes and have become key surrogate endpoints for evaluating the therapeutic efficacy of contemporary treatments for heart failure with reduced ejection fraction (HFrEF). In this review, we critically evaluate recent published data (2015-2016) from randomized clinical trials (RCTs) and observational studies of HFrEF therapies to assess the role of ventricular remodeling on outcomes.

These data highlight the benefits of certain guideline-directed medical therapies (GDMT) such as cardiac resynchronization therapy, surgical revascularization, and mechanical circulatory support on remodeling, while revealing the limitations of other therapies-routine mitral valve repair for patients with moderate ischemic mitral regurgitation and adjuncts to percutaneous coronary intervention in patients with ST elevation myocardial infarction (cyclosporine A and bioabsorbable cardiac matrix). The new angiotensin receptor blocker/neprilysn inhibitor, sacubitril/valsartan, demonstrates convincing improvements in clinical outcomes with a study of remodeling parameters to follow; the new cardiac myosin activator, omecamtiv mecarbil, demonstrates improvement in remodeling parameters without a clear early clinical benefit. The concepts and contemporary trials reviewed in this paper reinforce the value of non-invasive measures of ventricular remodeling (LVEF, LVESV, and LVEDV) as important metrics across a range of cardiovascular therapies. Global non-invasive measures of cardiovascular remodeling have roughly paralleled or preceded hard clinical outcomes. Additionally, the capacity for reverse remodeling in HFrEF with GDMT motivates continued research in the fields of implementation science, diagnostic imaging, and gene-based therapeutics.