HIGH-LEVELS OF PLASMA ATRIAL-NATRIURETIC-FACTOR AND IMPAIRED LEFT-VENTRICULAR DIASTOLIC FUNCTION IN HYPERTENSIVES WITHOUT LEFT-VENTRICULAR HYPERTROPHY

Objective: To seek possible correlations between plasma atrial natriuretic factor (ANF) and left ventricular diastolic function (LVDF) in hypertensive patients. Design: Since LVDF abnormalities can be detected in patients with normal left ventricular mass, we studied a group of hypertensive patients without left ventricular hypertrophy. Methods: Untreated hypertensive patients (n = 23) and normotensive control subjects (n = 19) were studied. LVDF indices were obtained by M-mode and pulsed Doppler echocardiography. Blood samples for plasma ANF were taken in the recumbent position from subjects on normal-sodium intake. Results: Plasma ANF levels were significantly higher in hypertensive patients than in normotensive subjects. All indices for systolic function were normal in both normotensive subjects and hypertensive patients. Left atrial diameter was significantly higher for hypertensive patients than for normotensive subjects. Considering LVDF, all indices for ventricular filling were found to be altered, on average, in hypertensive patients, the only exception being peak early, velocity. In addition, significant correlations were found between plasma ANF and the pulsed Doppler parameters of left ventricular filling, peak atrial velocity and the peak early: peak atrial velocity ratio. Overall correlations between plasma ANF and left atrial diameter, and between left atrial diameter and left ventricular mass index were also observed. Conclusions: The high levels of plasma ANF observed in our hypertensive patients and their correlation with the LVDF indices (which mainly reflect the atrial contribution to ventricular filling) could be the result of an increased atrial stretch due to diastolic ventricular dysfunction. This may exist in hypertensive patients before the development of ventricular hypertrophy.