Angiographic and clinical characteristics associated with the removable plaque components by means of thrombectomy catheters in patients with myocardial infarction.

Background: Previous studies have demonstrated that atheroembolism during percutaneous coronary intervention is associated with myocardial damage. The purpose of this study is to investigate the clinical and angiographic characteristics related to removable plaque elements in patients undergoing thrombectomy for myocardial infarction.

Methods: Eighty consecutive lesions in 80 patients (M/F=58/22, age 65.5+/-11.6 years) with myocardial infarction who underwent thrombectomy (TVAC system, Nipro, Osaka, Japan) prior to mechanical dilatation (balloon angioplasty and/or stent implantation) were investigated. Visible debris was collected and plaque elements (cholesterol clefts and/or foamy cells) were investigated pathologically. Baseline angiographic characteristics [baseline thrombolysis in myocardial infarction (TIMI) grade, culprit lesion, haziness, lesion length, ostium, bifurcation, calcification, eccentricity, thrombus, and multivessel] were analyzed, and predictive angiographic and clinical factors for plaque elements were investigated.

Results: There were no complications related to thrombectomy. Final TIMI grade 3 and blush grade 2 or 3 were achieved in 75 (94%) and 66 (83%) patients, respectively. Visible debris specimens were obtained in 49 (61%) patients. Histological plaque elements (cholesterol clefts and/or foamy cells) were observed in 27 out of 49 patients with debris specimens. There was no significant difference in the clinical characteristics between the groups of patients with (group P) and without (group NP) plaque elements. Aspirated plaque elements were more frequently observed in discrete and eccentric lesions (group P vs. group NP: discreteness, 52% vs. 28%, P<.05; eccentricity, 67% vs. 36%, P<.05).

Conclusions: This study demonstrated the clinical characteristics associated with removable plaque components in patients with myocardial infarction undergoing thrombectomy by means of the TVAC system. Discreteness and eccentricity were more frequently observed in lesions with removable plaque elements.