The heart is supplied by coronary arteries, which arises from the aortic valve.
The left coronary artery divides into left circumflex artery and left anterior descending artery aka anterior interventricular branch.
Various anastomoses and collaterals are formed between branches of the left and right coronary artery. No symptoms of Ischemic Heart Disease (IHD) are noticeable until more than 70% of coronary artery lumen is occluded. The risk of myocardial infarction increases when more than 90% of the arterial lumen is occluded.
Cardiac veins will collect blood from the capillaries of the myocardium and will drain into the coronary sinus. Coronary sinus will drain this deoxygenated blood back to the right atrium.
Blood supply to the heart
Coronary artery occlusion in myocardial infarction
Innervation of the heart
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