OCT findings in patients with recanalization of organized thrombi in coronary arteries

Abstract

Objectives: The purpose of this study was to determine the angiographic and optical coherence tomographic (OCT) characteristics of coronary lesions with recanalized thrombi.

Background: Although spontaneous recanalization of thrombi has been reported pathologically, it is rarely recognized in clinical practice.

Methods: Based on histopathologic features, recanalization of thrombi was defined by characteristics on OCT.

Results: Recanalization of thrombi was identified in 6 patients (3 male, 3 female; median age 63 years; age range 54 to 72 years). Based on symptoms, 3 patients were diagnosed with unstable angina; 2 were diagnosed with stable angina; and 1, who had mitral stenosis and huge left atrial thrombi, was diagnosed with post-infarct angina. All had normal serum concentrations of cardiac markers at admission. Angiography showed irregular linear filling defects and haziness. Two patients with near total occlusion had Thrombolysis In Myocardial Infarction (TIMI) flow grade 1 and collaterals, whereas 4 patients had TIMI flow grade 3 and no collaterals. All patients showed OCT findings consistent with recanalized thrombi, which consisted of signal-rich, high backscattered septa that divided the lumen into multiple small cavities communicating with each other. These structures, which had smooth inner borders, created a "Swiss cheese" appearance. Percutaneous coronary intervention was performed in 5 patients with angiographic slow flow or inducible-ischemia as documented by invasive or noninvasive stress tests. The remaining 1 patient with restored coronary flow underwent mitral valve surgery and left atrial thrombectomy.

Conclusions: OCT provided details on the characteristics of the organization of thrombi in both chronic total occlusion and subtotal narrowing. Coronary lesions containing recanalized thrombi were characterized by multiple small channels, with most showing functional significance.