Family history of myocardial infarction and hemodynamic responses to exercise in young black boys.

The influence of family history of coronary artery disease on children's hemodynamic responses to exercise was examined with 25 black boys aged 7 to 10 years. Blood pressure, heart rate, cardiac output, stroke volume, and total peripheral resistance were evaluated during preexercise, peak exercise, and recovery stages. Children with a family history of CAD exhibited greater systolic blood pressure and total peripheral resistance during preexercise and peak exercise stages than did those without a family history of coronary artery disease. After controlling for preexercise differences, the group with a family history of coronary artery disease exhibited greater increases in systolic blood pressure and less attenuation of total peripheral resistance to peak exercise than the group without a family history of coronary artery disease. Cardiac output indexed by body surface area and stroke volumes were higher at all times in the group without a family history compared with the group with a family history of coronary artery disease. Findings are compared with those of adult studies in terms of influence of family history of coronary artery disease on cardiovascular reactivity to stress.