slow-flow phenomenon
Reduced coronary flow velocity despite absence of mechanical obstruction, often occurring during intervention.
Full Definition
Slow-flow phenomenon refers to impaired coronary blood flow characterized by delayed contrast clearance in the absence of significant mechanical obstruction such as thrombus, dissection, or severe residual stenosis. This condition can occur spontaneously or as a complication of percutaneous coronary intervention, particularly in vessels with high thrombus burden or microvascular dysfunction. Unlike no-reflow phenomenon, slow flow typically responds better to pharmacologic intervention with vasodilators, antiplatelet agents, or calcium channel blockers. The phenomenon is associated with worse clinical outcomes and requires prompt recognition and treatment to optimize myocardial perfusion.
Usage
Usage note: Distinguish from no-reflow phenomenon in severity and treatment response.
In Context
- "The patient developed slow-flow phenomenon following stent deployment, which improved with intracoronary adenosine." — Interventional complication report
- "TIMI 2 flow with slow-flow phenomenon was observed in the culprit vessel following primary PCI." — STEMI procedure note