Systolic time intervals for left and right ventricles of swine

Because swine are used often in cardiovascular research, and because systolic time intervals (durations of preejection and ejection) are useful in evaluating the ventricular function in health and disease and the effects of drugs on ventricular function, systolic time intervals for left and right ventricles were obtained from 12 healthy anesthetized shoats. Catheter-tip micromamonmeters were placed just distal to the semilunar valves, and pressure pulses from these positions in the ascending aorta and pulmonary trunk were simultaneously recorded with an electrocardiograph at paper speed of 200 mm/second on a photographic oscillograph. Equations of regression relating preejection period (PEP) and ejection time (ET) for the left ventricle (L) to heart rate (HR) are as follows: PEPL = 53 + 0.56 HR ETL = 329 -- 0.94 HR Systolic time intervals for the right ventricle did not relate to heart rate.