STRUCTURAL CARDIAC CHANGES IN RELATION TO 24-H AMBULATORY BLOOD-PRESSURE LEVELS IN BORDERLINE HYPERTENSION

Objectives. To investigate left ventricular hypertrophy (LVH) in relat ion to 24-h ambulatory blood pressure (24-ABPM) and insulin levels in borderline hypertension. Design. A case-control study. Subjects. Borde rline hypertensive men (diastolic blood pressure (DBP) 85-94 mmHg, n = 69) and age-matched normotensive controls (DBP less than or equal to 80 mmHg, n = 69) from a population screening programme. Main outcome m easures. Echocardiography (M-mode), insulin (RIA) and 24-APBM (Del Mar P-IV) levels. Results. The borderline group showed a significant incr ease 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 significan tly higher in the borderline group (1.13+/-0.14 us. 1.06+/-0.14, P < 0 .01). Casual BP levels did not correlate with LVH indices, while 24-AB PM systolic levels correlated strongly with LVH indices in the borderl ine group (r = 0.22-0.52, P < 0.05) but not in the normotensive group. Insulin levels correlates strongly with LVH indices in the normotensi ve group (r = 0.34-0.47, P < 0.01) but not the borderline, group. Conc lusions. Signs of asymmetric LVH and altered ventricular function are already detectable in borderline hypertension. The data also suggest t hat early structural cardiac changes are related to ambulatory blood p ressure profile, but not to casual blood pressure or trophic factors s uch as insulin.