Spectrum of treadmill exercise responses in Africans with normotension, essential hypertension and hypertensive heart failure.

Hypertension is an important and common risk factor for cardiovascular morbidity and mortality in Africans. In Africans, hypertension carries a more dismal prognosis for target organ damage. We therefore studied the influence of blood pressure on treadmill exercise performance in normotensives, hypertensives and patients with hypertensive heart failure, matched for age and sex. The spectrum of response was a progressive diminution of the systolic rise in blood pressure during exercise, exercise-induced tachycardia, exercise time, and maximal oxygen intake. There was an increase in functional aerobic impairment with a rank order from normotensives to WHO I hypertensives, then WHO II, with a non-linear extreme rise with the onset of heart failure. The results indicate that impaired exercise performance in African hypertensives occurs with the onset of ventricular hypertrophy, and that this is accentuated by the neuroendocrine response in congestive heart failure.