Coronary anatomy and the regulation of coronary blood flow
Coronary territories and dominance, why the subendocardium is vulnerable, coronary perfusion pressure, metabolic autoregulation and flow reserve, the physiology behind FFR, vasodilator stress testing and microvascular dysfunction, and how anti-anginal drugs balance supply and demand.
Tier 2Medical sciences concept
Written with AI assistance and fact-checked against the sources below. For exam study, not clinical decisions. How notes are made
At a glance
- The heart takes about 5% of cardiac output (about 250 mL/min) and extracts 70 to 75% of delivered oxygen at rest. It can only meet more demand by raising flow.
- LV flow is mostly diastolic, because systole compresses intramural vessels. The subendocardium is most vulnerable.
- Flow is held constant over a wide pressure range by autoregulation, driven by metabolic vasodilators (adenosine, NO, K-ATP channel opening, hypoxia, CO2, H+).
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Sources
- Guyton and Hall Textbook of Medical Physiology (14th ed.)Elsevier (Hall and Hall, 2021), 2021
- Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine (12th ed.)Elsevier (Libby et al., 2022), 2022
- 2024 ESC Guidelines for the management of chronic coronary syndromesEuropean Society of Cardiology (Eur Heart J 2024;45:3415-3537), 2024
- Physiologic basis for assessing critical coronary stenosisAmerican Journal of Cardiology 1974;33:87-94 (Gould, Lipscomb and Hamilton), 1974
- ASNC Practice Point: Pharmacological stress testing with regadenosonAmerican Society of Nuclear Cardiology, 2024
- Last updated
- 14 November 2026
What changed
- 14 November 2026 Personal emails, About story and Australian-style copy