RELATIONSHIP BETWEEN BLOOD-PRESSURE MEASURED IN THE CLINIC AND BY AMBULATORY MONITORING AND LEFT-VENTRICULAR SIZE AS MEASURED BY ELECTROCARDIOGRAM IN ELDERLY PATIENTS WITH ISOLATED SYSTOLIC HYPERTENSION

Objective: To assess the additional diagnostic precision conferred by ambulatory blood pressure monitoring on clinic blood pressure measurem ent in evaluating the severity of isolated systolic hypertension. Meth ods: The association between left ventricular size as determined by EC G voltages [R-wave voltages in lead V5 (RV5) and S-wave voltages in le ad V1 (SV1)] and blood pressure as assessed by clinic measurements and ambulatory blood pressure monitoring was studied in 97 elderly patien ts included in the placebo run-in phase of the Syst-Eur trial. The add itional diagnostic precision conferred by ambulatory monitoring on cli nic blood pressure measurements was assessed by relating the residual ambulatory blood pressure level to the ECG-left ventricular size. The residual ambulatory blood pressure level was calculated by subtracting the predicted ambulatory blood pressure level for each patient (using the linear regression equation relating both techniques for the group ) from the observed ambulatory blood pressure. Results: Clinic systoli c blood pressure was on average 20 mmHg higher (P < 0.001) than daytim e ambulatory blood pressure while diastolic blood pressure was similar with both techniques. The sum of SV1 + RV5 was significantly related to clinic systolic pressure (r = 0.25), and 24-h (systolic, r = 0.37; diastolic, r = 0.29), daytime (systolic, r = 0.30; diastolic, r = 0.19 ) and night-time (systolic, r = 0.33; diastolic, r = 0.28) ambulatory blood pressure levels. These findings were not affected by adjustment for gender, age and the body mass index. The sum of SV1 + RV5 was sign ificantly related to the residual 24-h (systolic, r = 0.30; diastolic, r = 0.31), daytime systolic (r = 0.20) and night-time (systolic, r = 0.31; diastolic, r = 0.29) ambulatory blood pressure monitoring levels .