Professional Technical In the Industry Vocabulary Test

CTO

Also written as: CTO — Chronic Total Occlusion

Chronic Total Occlusion, a completely blocked coronary artery with TIMI 0 flow for duration greater than three months.

Full Definition

Chronic Total Occlusion (CTO) refers to a complete coronary artery blockage with Thrombolysis in Myocardial Infarction (TIMI) grade 0 flow that has been present for at least three months. CTOs are found in approximately 20% of patients undergoing coronary angiography and represent one of the most challenging lesion subsets for percutaneous coronary intervention. Successful CTO revascularization can improve angina symptoms, left ventricular function, and exercise tolerance, though the procedures require specialized techniques and equipment with longer procedure times and higher radiation exposure.

Usage

Usage note: Three-month duration criterion distinguishes from acute total occlusions; often requires specialized CTO operators.

In Context

"The RCA CTO was successfully opened using retrograde approach via septal collaterals." — Interventional cardiology procedure note
"CTO-PCI should be considered in patients with viable myocardium and refractory angina despite optimal medical therapy." — Clinical practice guideline

Also known as

chronic total occlusion totally occluded vessel

Contrasted with

patent vessel TIMI 3 flow

Don't confuse with

acute occlusion subtotal occlusion severe stenosis

CRUSADE score ← Back to glossary culprit vessel