Bugni W J, Ayers C W, Ashby R, Bittle P A, Ramirez G
Department of Internal Medicine, James A. Haley Veterans Administration Hospital, Tampa, Florida 33612.
Am J Cardiol. 1989 Feb 15;63(7):452-6. doi: 10.1016/0002-9149(89)90318-4.
Eight mildly to moderately hypertensive subjects free of any antihypertensive medications and on a normal salt diet performed maximal supine arm exercise. Before starting the exercise, a right-sided cardiac catheterization was performed to measure hemodynamic parameters before and during exercise. All patients had normal increases in cardiac output for the level of exercise performed and the peripheral vascular resistance diminished appropriately. An increase in the right atrial and pulmonary artery wedge pressures during exercise could be explained by increased venous return. After the baseline testing, rest and exercise hemodynamics were repeated 2 hours after the administration of 400 mg of dilevalol, a new beta blocker. For the next 2 weeks the patients received 400 mg of the study drug twice a day, with repeat studies obtained thereafter. As with other beta blockers, dilevalol decreases the heart rate and cardiac output on exercise, but, in addition, it induces a decrease in the resting systemic vascular resistance. This action is similar to its isomer, labetalol.
八名轻度至中度高血压患者,未服用任何抗高血压药物,且饮食为正常盐摄入,进行了最大程度的仰卧位手臂运动。在开始运动前,进行了右侧心导管插入术,以测量运动前和运动期间的血流动力学参数。所有患者在进行运动时心输出量均有正常增加,外周血管阻力也相应降低。运动期间右心房和肺动脉楔压升高可由静脉回流增加来解释。在基线测试后,给予400毫克新型β受体阻滞剂双醋洛尔2小时后,重复进行静息和运动血流动力学测试。在接下来的2周内,患者每天服用两次400毫克研究药物,此后再次进行测试。与其他β受体阻滞剂一样,双醋洛尔可降低运动时的心率和心输出量,但此外,它还会使静息时的全身血管阻力降低。这种作用与其异构体拉贝洛尔相似。