A084: Spectral analysis of blood pressure variability before and after exercise during angiotensin antagonism

We evaluated the effects of tasosartan (TASO), a specific antagonist of AT1 receptors, on blood pressure (BP) variability before and after exercise. Twenty hypertensive patients (48 ± 2 years, 78 ± 3 kg, 28 ± 1 kg/m2, mean ± SEM) participated in this randomized, double-blind crossover, placebo-controlled study. Each patient received TASO (100 mg/d) or placebo (PLAC) during two periods of two weeks separated by two weeks of wash out. Beat by beat systolic (SBP) and diastolic blood pressures (DBP) were measured by a photoplethysmographic device (Finapress) and recorded on a computer during 10 minutes before and after an exercise period of 30 minutes on a stationary bicycle at 50% of VO2max. Autonomic nervous system activity was evaluated by spectral analysis of SBP and DBP variability using the low frequency band (0.05–0.15 Hz, LF power, in ms2/Hz), to assess sympathetic activity and the high frequency band (0.15–0.4 Hz, HF power, ms2/Hz) to assess parasympathetic activity. The LF/HF ratio was taken as an index of sympathovagal balance. (See Table) Pre-exercise Post-exercise PLAC TASO PLAC TASO BP SBP 144 ± 4 132 ± 3*** 141 ± 3† 126 ± 3***,††† DBP 92 ± 2 87 ± 1*** 92 ± 1 84 ± 1***,† LF: SBP 24.1 ± 2.7 25.6 ± 2.9 21.6 ± 2.5 19.2 ± 2.4† DBP 34.7 ± 4.1 37.4 ± 4.3 32.0 ± 4.0 31.5 ± 3.7† HF: SBP 7.0 ± 1.3 9.1 ± 2.1 7.2 ± 1.4 5.5 ± 1.1† DBP 7.0 ± 1.1 7.9 ± 1.3 6.1 ± 1.0 4.9 ± 0.9† LF/HF: SBP 5.8 ± 1.4 4.9 ± 0.8 5.2 ± 1.3 5.3 ± 0.8 DBP 8.5 ± 2.8 6.2 ± 0.9 9.2 ± 2.7 8.8 ± 1.2† *P < 0.05, ***p < 0.001 vs PLAC; †