Prediction of left ventricular geometry by clinic, pre-dialysis and 24-h ambulatory BP monitoring in hemodialysis patients: CREED investigators.

Abstract

Arterial hypertension is an established risk factor for left ventricular hypertrophy (LVH) in the uremic population. However, whether 24-h monitoring is a better predictor of LVH than clinic blood pressure and routine pre-dialysis measurements in these patients is still undefined. This problem was studied in 64 nondiabetic hemodialysis patients without heart failure. The echocardiographic study as well as the clinic and 24-h ambulatory blood pressure (BP) measurements were performed during the day off-dialysis. Pre-dialysis arterial pressure was calculated as the average value of the 12 routine recordings taken during the month preceding the study. In multivariate models, including also sex, body mass index, hematocrit and serum cholesterol, pre-dialysis systolic, diastolic and pulse pressures were the only independent BP determinants of heart geometry. Twenty-four hour ambulatory BP monitoring (ABPM) did add significant (but weak) information to the prediction of left ventricular internal dimension, i.e. it increased by 9% (P = 0.01) the variance already explained by pre-dialysis diastolic BP and other significant covariates. However, 24-h ABPM did not add any significant and independent explanatory information to the corresponding pre-dialysis measurements for the posterior wall and interventricular septum measurements, and for left ventricular mass (-0.6 to +3.9%; average +1.1%). In dialysis patients, pre-dialysis BP is at least as strong a predictor of left ventricular mass as 24-h ambulatory monitoring. Thus, the average of 12 routine pre-dialysis measurements may be used to predict heart geometry in dialysis patients without any loss of information in comparison with 24-h ambulatory monitoring.