Right Ventricle and Exercise Capacity

Almost 3 quarters of a century ago, an experimental dog model, involving the electrocautery ablation of the free wall of the right ventricle (RV), served as the basis for the contention that the RV serves functionally as a passive conduit. Clearly, our understanding of the RV has evolved over subsequent decades, and the prognostic significance of RV dysfunction is now recognized in a wide array of disorders including left heart dysfunction and pulmonary hypertension among others. Despite significant strides in elucidating the role of the RV in overall cardiac function on the one hand and in disease states on the other, both quantification and qualification of RV function remain challenging because of several inter-related factors. First, the RV has a complex geometry; second, the role of ventricular interaction in overall pump performance remains unclear; third, assessment of RV diastolic function is challenging and far from routine in a typical echocardiographic laboratory; and fourth, the role of the pericardium in pump performance, especially that of pericardial constraint during exercise, also influences the ability to both qualify and quantify RV function. The challenges in noninvasively assessing RV function at rest are only compounded when attempting to evaluate performance with exercise.