Relation of stress testing and ambulatory blood pressure to hypertensive cardiac damage

In essential hypertension, the severity of cardiovascular damage is only weakly related to clinic blood pressure (BP), whereas a better relationship seems to exist with BP recorded during stressful situations. The present study compared BP levels measured during laboratory stress testing and 24-h ambulatory monitoring with regard to their relationship with cardiac end-organ involvement. BP recorded during a mental and a physical challenge and during 24-h ambulatory monitoring was related to Doppler echocardiography characteristics of left ventricular structure and filling in 63 untreated essential hypertensives and in 32 healthy subjects. In the hypertensive group, only a weak relationship was observed between left ventricular mass and clinic BP; the strength of this association was not improved by BP measured during mental task and cycle ergometry, and was slightly but not significantly higher for BP recorded during ambulatory monitoring. In multivariate analysis, left ventricular mass was independently predicted by stroke index and 24-h systolic BP. Among the different pressure measures, 24-h, daytime, and nighttime BPs bore the only significant relation to relative wall thickness. In the normotensive group, no significant relationship was observed between left ventricular mass and different measures of BP. Doppler indexes of left ventricular diastolic filling did not significantly relate to any BP measurement in the hypertensive group, and generally bore a significant inverse relationship to various BP recordings in the normotensive group. To summarize, stress testing BP does not help in identifying hypertensive patients with increased left ventricular mass.