Right coronary arterial blood flow and myocardial oxygen consumption are significantly lower per unit weight of tissue than in the left ventricle, and right ventricular oxygen extraction increases during stress unlike the left ventricle.
Does right ventricular oxygen metabolism differ from left ventricular oxygen metabolism in response to cardiac loading in open-chest dogs?
Right ventricular oxygen metabolism relies on both increased coronary blood flow and increased oxygen extraction to meet higher oxygen demands, unlike the left ventricle which relies primarily on increased blood flow.
Absolute Event Rate: 8.6% vs 4%
p-value: p=<0.01
A comparison of blood flow and myocardial oxygen consumption (MVO2) in the right and left ventricles was made in 24 open-chest dogs. Simultaneous measurements were made of the left anterior descending (LAD) and right coronary arterial (RC) blood flow, and of O2 saturation in the coronary sinus and in from one to four anterior cardiac veins. Blood flow was greater in the LAD than in the RC, 87.4±36.0 and 46±22.0 ml/min/100g, respectively. The O2 extraction was 51.3±11.0 in the anterior cardiac veins and 60.0±6.3% in the coronary sinus. The mean MVO2 was greater for the left than for the right ventricles, 8.6±3.3 vs. 4.0±2.1 ml/min/100g. An increase in LAD flow without an increase in O2 extraction accounted for the enhancement of MVO2 of the left ventricle induced by pacing, isoproterenol or methoxamine. In contrast, pacing, isoproterenol or constriction of the pulmonary artery increased MVO2 of the right ventricle with an increase in both O2 extraction and right coronary blood flow. These results indicate that the right coronary arterial blood flow is lower per unit weight of tissue and is less dependent on MVO2 than is LAD blood flow.
Shozo Kusachi (Sat,) conducted a other in Normal physiology (animal model) (n=24). Left ventricle (compared to right ventricle) vs. Right ventricle was evaluated on Mean myocardial oxygen consumption (MVO2) at baseline (ml/min/100g) (p=<0.01). Right coronary arterial blood flow and myocardial oxygen consumption are significantly lower per unit weight of tissue than in the left ventricle, and right ventricular oxygen extraction increases during stress unlike the left ventricle.