[Resting and exercise hemodynamics in essential arterial hypertension]

Various haemodynamic functions were studied in 70 patients (51 men and 19 women; mean age 53.0 +/- 7.0 years) with essential hypertension. The following parameters were measured, at rest and on exercise: systolic and diastolic blood pressure, heart rate, mean pulmonary artery pressure, cardiac output and peripheral vascular resistance. 15 normotensive subjects (11 men and four women; mean age 54.4 +/- 7.2 years) without significant cardiovascular disease served as controls. Resting peripheral vascular resistance (PAP) in the hypertensives was, at 1634.7 +/- 239.0 dyn/s.cm-5, higher by 41%, on exercise at 1029.4 +/- 105.9 higher by 14%, than in the controls (at rest 1157.1 +/- 118.9 dyn/s.cm-5, on exercise 706.9 +/- 94.1 dyn/s.cm-5; P less than 0.0001). Cardiac output at rest was 9.6% lower, on exercise 8.0% lower than in the controls (neither change significant). Thus the increased peripheral vascular resistance was the sole cause of the increased blood pressure. Mean PAP, as a measure of left-ventricular filling pressure, in hypertensives was 14.7 +/- 3.9 mm Hg at rest, 34.9 +/- 7.8 mm Hg on exercise, an increase of 14% and 40%, respectively, over the control values of 12.7 +/- 1.9 mm Hg at rest and 24.4 +/- 2.8 mm Hg on exercise (P less than 0.0001). The raised left-ventricular filling pressure is an indication of early hypertensive heart disease.