@8 months ago with 12 notes
What is Coronary steal ?
It is caused when there is narrowing of the coronary arteries and a coronary vasodilator is used.
In coronary artery disease, collateral microvessels bypasses the occulded area and allow supplemental blood flow to myocardium distal to occulsion.
When those patients use drugs such as adenosine and dipyridamole, which are selective vasodilators of coronary vessels, coronary steal phenomenon occurs ― that is, vasodilation of coronary arterioles in normal area ,wheres reduced blood flow to ischemic area.
This mechanism is used in drug-based cardiac stress tests; When a patient is incapable of doing physical activity they are given a vasodilator.