Structural Abnormalities and Not Diastolic Dysfunction Are the Earliest Left Ventricular Changes in Hypertension

It has been claimed that diastolic dysfunction is the earliest cardiac abnormality in hypertension, preceding the development of left ventricular (LV) structural abnormalities. To detect early signs of hypertensive cardiac involvement 722 subjects (533 men and 189 women), 18-45 years old, with stage I hypertension, were studied by M-mode and Doppler echocardiography. Blood pressure was measured by 24-h ambulatory monitoring. Ninety-five normotensive individuals of similar age and gender distributions were studied as controls. Significant, though modest, changes of LV mass and geometry were found in the participants in comparison with the normotensive controls. The increment was +10.4 g/m2 for LV mass index, +1.8 mm for LV wall thickness, and +0.032 for relative wall thickness. A slight increase in atrial filling peak velocity was found in the hypertensive subjects at Doppler analysis of transmitral flow, but the ratio of early to atrial velocity of LV diastolic filling did not differ between the two groups. In multiple regression analyses, which included age, body mass index, heart rate, smoking, and physical activity, 24-h mean blood pressure emerged as a significant predictor of LV mass index (men, P = .003; women, P = .04) and wall thickness (men, P = .03; women, P = .004) in the hypertensive subjects, whereas no index of diastolic filling was significantly associated with ambulatory blood pressure in either gender. The present data indicate that changes in LV anatomy are the earliest signs of hypertensive cardiac involvement. Left ventricular filling is affected only marginally in the initial phase of hypertension.