Right ventricular adaptation and maladaptation in chronic pulmonary arterial hypertension.

The right ventricle (RV) is not well suited to chronic pressure overload and often fails to adequately compensate. Mechanisms that allow the RV to respond to acute pressure overload often become maladaptive and contribute to its failure, including the effects of pulmonary hypertension on RV myocardial perfusion, the influence of interventricular dependence on RV function, and metabolic shifts in the RV myocardium from fatty acid to glycolysis. Medications to treat pulmonary hypertension have focused on pulmonary vasodilatation. Their effects on RV function may determine their effectiveness. How new medications affect right ventricular performance must be addressed.