Cardiac Plasticity

This review explains how the heart responds to physiologic or pathologic conditions. Exercise, pregnancy, and postnatal growth cause physiologic growth; neurohumoral activation, hypertension, and myocardial injury cause hypertrophic growth, which increases the risk of heart failure and malignant arrhythmia. Atrophy of the heart can arise from protracted bed rest, prolonged weightlessness, or mechanical unloading with a ventricular assist device.