Coronary blood flow (CBF) is regulated in order to match oxygen requirements by myocardial cells and may increase up to fivefold, compared to baseline (coronary flow reserve), due to maximal myocardial oxygen demand, as a result of maximal dilatation of small resistance coronary arteries (arterioles and pre-arterioles). The regulation of CBF is mediated by metabolic, neural, circulating, and physical (vascular and extravascular) factors. An inadequate CBF for myocardial oxygen requirement results in myocardial ischemia. The pathophysiologic mechanisms responsible for myocardial ischemia (either in conditions of increased oxygen requirement or at rest) include atherosclerotic coronary flow-limiting stenosis, epicardial coronary artery spasm, coronary microvascular dysfunction and coronary thrombosis.
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)