Coronary Hemodynamic Effects of Increasing Ventricular Rate in the Unanesthetized Dog

摘要: In five unanesthetized dogs with surgical heart block, increasing ventricular rate from 50--75 to 250--300 beats/min demonstrated an optimum of 130 185, above which aortic pressure and cardiac output fell. contrast, coronary blood flow continued rise a 250 300 beats/min. Stroke systolic was well maintained over the entire range rates studied, while stroke diastolic fell increase rate. A reactive hyperemic response following release 1- 10-second artery occlusion at suggests that fall in occurred these may not be due insufficiency total flow. Beta-receptor activity did appear play significant role hemodynamic adjustment increases within for 52--77 115--156