Effect of betaxolol hydrochloride on heart rate variability indices during exercise stress testing in patients with hypertension.
Betaxolol hydrochloride is a beta1-selective antagonist that produces vasodilation in patients with hypertension and ischemic heart disease. The goal of the present study was to characterize the effect of betaxolol on heart rate variability indices (HRV), a well-established prognostic marker. Symptom limited-treadmill exercise testing was performed in 17 hypertensive patients (60.9 +/- 14.8 years-old) before and immediately a 3 weeks course of betaxolol hydrochloride (5 mg daily). Frequency domain HRV (high frequency spectra, HF; 0.15-0.40 Hz: low frequency spectra, LF; 0.04-0.15 Hz) was measured during exercise treadmill testing using MemCalc software. Betaxolol hydrochloride significantly decreased the maximal systolic blood pressure and heart rate (184 +/- 29 vs. 156 +/- 26 mmHg, P < 0.01; 132 +/- 21 vs. 113 +/- 15 bpm, P < 0.01) and significantly increased HF and LF during exercise treadmill testing (HF, 32 +/- 36 vs. 56 +/- 55 men/Hz, P < 0.01; LF, 64 +/- 58 vs. 95 +/- 86 men/Hz, P < 0.01). Thus, treatment with betaxolol hydrochloride resulted in a decrease in blood pressure during exercise treadmill testing and in an increase in HRV. This suggests that this agent could have beneficial effects on long-term prognosis in patients with hypertension.
Takase
B
B
Division of Biomedical Engineering, National Defense Medical College Research Institute, 3-2 Namiki, Tokorozawa, Saitama 359-8513, Japan. bonpeit@ndmc.ac.jp
Abe
Y
Y
Nagata
M
M
Matsui
T
T
Hattori
H
H
Ohsuzu
F
F
Ishihara
M
M
Kurita
A
A
D000319:Adrenergic beta-Antagonists / Q000494:pharmacology*; D000368:Aged; D000369:Aged, 80 and over; D015784:Betaxolol / Q000494:pharmacology*; D001794:Blood Pressure / Q000187:drug effects; D003327:Coronary Disease / Q000453:epidemiology; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005260:Female; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D016037:Single-Blind Method
D000319:Adrenergic beta-Antagonists; D015784:Betaxolol