no-reflow phenomenon
Impaired myocardial perfusion despite successful restoration of epicardial coronary flow during percutaneous intervention.
Full Definition
The no-reflow phenomenon describes the absence of adequate myocardial tissue perfusion despite successful restoration of flow in the epicardial coronary artery during primary percutaneous coronary intervention. This occurs due to microvascular obstruction from distal embolization of thrombotic material, inflammation, or spasm of the microvasculature. No-reflow can be detected during angiography by poor contrast penetration and clearance, and is associated with larger infarct size, reduced left ventricular function recovery, and worse clinical outcomes.
Usage
Usage note: Distinguish from mechanical obstruction; often requires assessment of myocardial blush grade or MRI confirmation.
In Context
- "Despite achieving TIMI 3 flow, the no-reflow phenomenon was evident with poor myocardial blush grade." — Primary PCI procedure note
- "Cardiac MRI confirmed microvascular obstruction consistent with no-reflow in the anterior territory." — Post-infarction imaging report