Pathophysiological studies on postalimentary lipemia with special reference to the effect of exogenous hypertriglyceridemia on intramyocardial tissue oxygen tension
Ishikawa, Y.
Kobe Journal of Medical Sciences 25(1): 19-37
1979
ISSN/ISBN: 0023-2513 PMID: 449258 Document Number: 140451
The pathophysiological significance of postalimentary lipemia in patients with ischemic heart disease (IHD) was elucidated. In patients with IHD and control subjects, the effects of high fat meal intake and the subsequent physical exercise on ECG, arterial O2 tension (PaO2) and plasma content of triglyceride (TG) and free fatty acid (FFA) were observed. In IHD group, significant ST depression was demonstrated in ECG 4 h after fat intake, although no change was observed in the control group. The physical exercise induced the augmentation and the appearance of ST depression in the IHD group and control group, respectively. In both groups PaO2 was decreased and plasma TG and FFA were increased after fat intake. Intramyocardial tissue O2 tension (PtO2) before and after the i.v. infusion of fat emulsion (Intralipid) was observed by using medical mass spectrometer (MS-8, SRI) in dogs under rapid atrial pacing of 170/min. Observations were made on coronary sinus flow (Cs-F). The effects of fat infusion on PtO2 and Cs-F were compared with those of saline infusion. PtO2 in the endocardial side was significantly lower than that in the epicardial side. PtO2 decreased during fat infusion, despite the fact that no change was found during saline infusion. No difference was found between Cs-F during fat infusion and that during saline infusion. Exogenous hypertriglyceridemia induces myocardial hypoxia, probably due to the disturbance of O2 diffusion.