Background—Increased left ventricular (LV) mass predicts an adverse outcome in patients with essential hypertension. The purpose of this study was to determine the relation between changes in LV mass during antihypertensive treatment and subsequent prognosis.

Methods and Results—Procedures including echocardiography and 24-hour ambulatory blood pressure (BP) monitoring were performed in 430 patients with essential hypertension before therapy and after 1217 patient-years. Months or years after the follow-up visit, 31 patients suffered a first cardiovascular morbid event. The patients with a decrease in LV mass from the baseline to follow-up visit were compared with those with an increase in LV mass. There were 15 events (1.78 per 100 person-years) in the group with a decrease in LV mass and 16 events (3.03 per 100 person-years) in the group with an increase in LV mass (P=.029). In a Cox model, the lesser cardiovascular risk in the group with a decrease in LV mass (hazard ratio [HR], 0.46; 95% CI, 0.22 to 0.99) remained significant (P=.04) after adjustment for age (HR, 1.06; 95% CI, 1.03 to 1.10; P=.0008) and baseline LVH at ECG (HR, 3.85; 95% CI, 1.52 to 9.78; P=.012). In that model, baseline LV mass bordered on statistical significance (HR, 1.01; 95% CI, 1.00 to 1.03; P=.06). In the subset with LV mass >125 g/m at the baseline visit (26% of subjects), the event rate was lower among the subjects who achieved regression of LVH than in those who did not (1.58 versus 6.27 events per 100 person-years; P=.002). This difference held in the multivariate analysis (HR, 0.18; 95% CI, 0.05 to 0.68).

Conclusions—In essential hypertension, a reduction in LV mass during treatment is a favorable prognostic marker that predicts a lesser risk for subsequent cardiovascular morbid events. Such an association is independent of baseline LV mass, baseline clinic and ambulatory BP, and degree of BP reduction.