Separation of effects of cardiovascular disease and age on ventricular function with maximal exercise.

Abstract To distinguish between the responses to maximal exercise caused by cardiovascular disease and those-caused by aging, the percent deviation of observed values of maximal pressure-rate products and maximal heart rates from age-predicted values in healthy subjects were derived for 2,094 healthy middle-aged men and eight subgroups of 2,291 ambulatory male patients. Highly significant differences in left ventricular impairment and heart rate impairment were obtained. When left ventricular impairment is subtracted from functional aerobic impairment derived by nomogram from duration of multistage exercise using the Bruce protocol, the residual difference represents the peripheral circulatory impairment. Peripheral circulatory impairment was significantly increased in hypertensive patients and in patients with the combination of cardiac disease, angina pectorls and increased blood pressure. The significance of these findings is that impairment of circulatory delivery of oxygen can now be partitioned into left ventricular and peripheral components. The left ventricular component comprises the heart rate and a noninvasive measurement of systolic pressure at maximal exercise, where each is related to age-adjusted normal values.