Left atrial dimension is related to blood pressure variability in newly diagnosed untreated hypertensive patients

Variability in daily blood pressure (BPV) recorded 24-h ambulatory blood pressure monitoring (ABPM) is known to be related to left ventricular hypertrophy and an increased incidence of cardiovascular events in hypertensive patients. The aim of this study was to evaluate whether left atrium dimension, which increases early in hypertensive subjects, was related to BPV in a group of 167 drug-naive patients (100M/67F, age: 46±11yr). The patients were chosen among those consecutively sent by their general practitioners to confirm the existence of arterial hypertension and afterwards diagnosed as hypertensive (mean 24-h ABPM ⩾130/80 mm Hg). In each patient, the left atrial posteroanterior diameter index for height (LADi) and the left ventricular mass standardized for body surface area (LVMi) were measured using standardized echocardiographic methods. BPV was calculated as the weighted mean of daytime and nighttime systolic and diastolic blood pressure s.d.'s (ws.d.), according to the formula ws.d.=[(daytime s.d. × 10)+nighttime s.d. × 6)]/16. An increase in left atrial dimension (LADi>24 mm m(-1)) was present in 36 patients (21.6% of the total population). In a univariate regression, LVMi was significantly related to systolic BPV (r=0.24; P=0.02) only in men, whereas LADi was significantly related to both systolic and diastolic BPV in both genders. After adjusting for sex, age, BMI, heart rate, diastolic function and estimated glomerular filtration rate, both systolic and diastolic BPV remained significantly related to LADi (P=0.02 for both) but not to LVMi. In conclusion, this study suggests that BVP, as measured as BPws.d., is significantly and independently associated with increased LADi in newly diagnosed, treatment-naive hypertensive patients.