Hemodynamic responses to ergometer exercise in children and young adults with left ventricular pressure or volume overload

This study determines (1) the hemodynamic responses to exercise in groups of young patients with either left ventricular (LV) pressure or volume overload, (2) whether these responses differed from healthy subjects when the variables of sex, age, race and body surface area were controlled (analysis of covariance), and (3) whether any of the exercise variables could predict noninvasively the severity of the gradient in aortic valve stenosis (AS). We tested 137 patients, including 70 with AS, 25 with aortic isthmic coarctation, 20 with aortic regurgitation and 22 with mitral regurgitation, and compared them with a control population of 405 healthy children. The children underwent a continuous, graded, maximal test with 3-minute stages. The variables evaluated were peak heart rate, systolic blood pressure, maximal work load (kgm/min), peak working capacity index (kg-m/min/ kg body weight) and ischemia on electrocardiography.In patients with pressure overload, the maximal exercise values for work load, heart rate and peak working capacity index were significantly different (p < 0.05) from control values. The patients with volume overload had higher blood pressure values than either control subjects or patients with pressure overload. Similarly, the values for heart rate in patients with volume overload were lower than values for control subjects and patients with pressure overload. No exercise variable was predictive of severity of AS. These data confirm some previous investigators' findings with respect to LV volume and pressure overload, but do not support the concept that exercise test results are sensitive and specific for the prediction of severity in AS.