Structural cardiac changes in relation to 24-h ambulatory blood pressure levels in borderline hypertension.

Abstract

OBJECTIVES: To investigate left ventricular hypertrophy (LVH) in relation to 24-h ambulatory blood pressure (24-ABPM) and insulin levels in borderline hypertension. DESIGN: A case-control study. SUBJECTS: Borderline hypertensive men (diastolic blood pressure (DBP) 85-94 mmHg, n = 69) and age-matched normotensive controls (DBP < or = 80 mmHg, n = 69) from a population screening programme. MAIN OUTCOME MEASURES: Echocardiography (M-mode), insulin (RIA) and 24-APBM (Del Mar P-IV) levels. RESULTS: The borderline group showed a significant increase in septal thickness (10.4 +/- 1.5 vs. 9.7 +/- 1.5 mm, P < 0.01), peak systolic wall stress (218 +/- 38 vs. 202 +/- 38 10(3) dynes cm-2, P < 0.05) and a decrease in LV ejection time (28.4 +/- 2.5 vs. 29.5 +/- 2.1s, P < 0.01). The septum vs. posterior wall thickness ratio was significantly higher in the borderline group (1.13 +/- 0.14 vs. 1.06 +/- 0.14, P < 0.01). Casual BP levels did not correlate with LVH indices, while 24-ABPM systolic levels correlated strongly with LVH indices in the borderline group (r = 0.22-0.52, P < 0.05) but not in the normotensive group. Insulin levels correlates strongly with LVH indices in the normotensive group (r = 0.34-0.47, P < 0.01) but not the borderline, group. CONCLUSIONS: Signs of asymmetric LVH and altered ventricular function are already detectable in borderline hypertension. The data also suggest that early structural cardiac changes are related to ambulatory blood pressure profile, but not to casual blood pressure or trophic factors such as insulin.