AMBULATORY 24-HOUR BLOOD-PRESSURE MONITORING - SIGNIFICANCE OF BLOOD-PRESSURE VARIABILITY FOR THE PROGRESSION OF CARDIAC-HYPERTROPHY

It is known that ambulatory blood-pressure monitoring gives a better prediction of target organ damage and prognosis than clinical blood pressure. Many studies have found a closer correlation for ambulatory blood pressure with left ventricular hypertrophy than clinical blood pressure. One question that is discussed controversely is whether the variability of blood pressure is also a determinant of target organ damage independent of the average level. In 52 patients with elevated casual blood pressure a 24-h ambulatory blood-pressure measurement (Space Labs 90202) was performed and left ventricular hypertrophy was evaluated by M-mode echocardiography. The following parameters of blood pressure variability were calculated from the profiles: the standard deviation of the mean value, the variation coefficient and the parameter of variability as proposed by Schachinger et al. (17). Furthermore a Fourier analysis of the blood pressure data was performed to quantify blood pressure variability. We found no statistically significant correlation between blood pressure variability and left ventricular mass. However, systolic and diastolic blood pressure level showed a significant correlation with left ventricular hypertrophy (r = 0.45 and r = 0.49, p < 0.05). Thus, blood pressure variability as calculated from the ambulatory, non-invasive blood pressure monitoring is a poor predictor for secondary damage of the heart.