no-reflow phenomenon
The failure to achieve adequate myocardial reperfusion despite successful reopening of an epicardial coronary artery.
Full Definition
No-reflow phenomenon occurs when microvascular obstruction prevents adequate tissue perfusion following restoration of epicardial coronary flow during primary percutaneous coronary intervention. This condition results from distal embolization of thrombotic debris, microvascular spasm, endothelial swelling, and inflammatory cell infiltration. No-reflow is associated with larger infarct size, reduced left ventricular function recovery, and worse clinical outcomes including increased mortality. It can be identified angiographically by TIMI flow grade 0-2 despite patent epicardial vessel, or by contrast echocardiography and cardiac MRI showing lack of microvascular perfusion. Prevention and treatment strategies include aspiration thrombectomy, glycoprotein IIb/IIIa inhibitors, and vasodilator therapy.
Usage
Usage note: Distinguish from epicardial vessel closure or spasm; refers specifically to microvascular dysfunction.
In Context
- "Despite successful stent deployment, the patient experienced no-reflow phenomenon with TIMI-1 flow in the distal vessel." — Primary PCI procedure note
- "Contrast echocardiography confirmed no-reflow phenomenon with absent microbubble opacification in the anterior wall." — Post-STEMI evaluation