TY - JOUR
T1 - Coronary and cardiac responses to exercise after chronic ventricular sympathectomy
AU - Gwirtz, Patricia A.
AU - Mass, Howard J.
AU - Strader, J. Robyn
AU - Jones, Carl E.
PY - 1988
Y1 - 1988
N2 - This study examined the effects of chronic surgical ventricular sympathectomy on the relationships between left ventricular mechanical performance, coronary blood flow, and exercise workload in sham-operated control dogs and dogs which had been ventricular sympalhectomized 8 wk earlier. During exercise, left ventricular global contractile state was less in sympathectomized ventricles than in control ventricles, as indicated by reduced systolic pressure and maximal rate of pressure generation. Regional contractile shortening was not different. Heart rate was significantly elevated in sympathectomized ventricles. Therefore, peak systolic pressure-heart rate product and tension-time index were not different in sympathectomized ventricles compared to control ventricles. However, at each level of exercise, mean coronary flow in sympathectomized ventricles was reduced by about 50% compared to control values. The slopes of coronary flow on pressure-rate product and tension-time index were also reduced No difference in left ventricular oxygen extraction between control and sympathectomized hearts were observed. Thus, chronic ventricular sympathectomy altered the relationships between coronary flow and oxygen consumption, on the one hand, and ventricular oxygen-dependent performance and whole-body exercise level, on the other hand.
AB - This study examined the effects of chronic surgical ventricular sympathectomy on the relationships between left ventricular mechanical performance, coronary blood flow, and exercise workload in sham-operated control dogs and dogs which had been ventricular sympalhectomized 8 wk earlier. During exercise, left ventricular global contractile state was less in sympathectomized ventricles than in control ventricles, as indicated by reduced systolic pressure and maximal rate of pressure generation. Regional contractile shortening was not different. Heart rate was significantly elevated in sympathectomized ventricles. Therefore, peak systolic pressure-heart rate product and tension-time index were not different in sympathectomized ventricles compared to control ventricles. However, at each level of exercise, mean coronary flow in sympathectomized ventricles was reduced by about 50% compared to control values. The slopes of coronary flow on pressure-rate product and tension-time index were also reduced No difference in left ventricular oxygen extraction between control and sympathectomized hearts were observed. Thus, chronic ventricular sympathectomy altered the relationships between coronary flow and oxygen consumption, on the one hand, and ventricular oxygen-dependent performance and whole-body exercise level, on the other hand.
KW - Coronary blood flow
KW - Exercise
KW - MyO-cardial tension-time index
KW - Myo-Cardial oxygen consumption
KW - Myo-cardial pressure-rate product
KW - Regional my O-cardial shortening
UR - http://www.scopus.com/inward/record.url?scp=0023917030&partnerID=8YFLogxK
U2 - 10.1249/00005768-198820020-00005
DO - 10.1249/00005768-198820020-00005
M3 - Article
C2 - 3367747
AN - SCOPUS:0023917030
SN - 0195-9131
VL - 20
SP - 126
EP - 135
JO - Medicine and Science in Sports and Exercise
JF - Medicine and Science in Sports and Exercise
IS - 2
ER -