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Cardiac adaptation to increased systemic blood pressure in borderline hypertensive men
B H Sung1, W R Lovallo, S M Teague
1Department of Medicine, State University of New York, Buffalo.
Abstract:
The present study examined cardiac characteristics of borderline hypertensive men with a positive parental history of hypertension. Hemodynamics in relation to left ventricular function and structure were evaluated in 15 borderline hypertensive men with a parental history of hypertension and in 20 normotensive control subjects with a negative parental history. Groups were matched in age, height, weight and percent body fat. Left ventricular mass and dimensions were measured by M-mode echocardiography, and left ventricular function was assessed by radionuclide ventriculography. Both groups had similar left ventricular mass, dimensions and wall thicknesses. In relation to control subjects, borderline hypertensive men had a significantly higher heart rate and blood pressure (BP) (p < 0.001), but a similar cardiac index. Borderline hypertensive men had a higher peripheral resistance index (p < 0.02), longer time to peak filling rate, and reduced cardiac efficiency, whereas they had higher contractility, minute and stroke work indexes than did control subjects (all p < 0.05); they also had higher diastolic BP (p < 0.03) during exercise, and sustained higher BP during recovery than did controls. Although this group of borderline hypertensive men did not have an altered cardiac anatomy, they had an increased vascular resistance, an altered diastolic function and a reduced cardiac efficiency while undergoing a greater work load. These cardiodynamic profiles are consistent with functional vascular changes and a parallel compensation by the heart.(ABSTRACT TRUNCATED AT 250 WORDS)