{Reference Type}: Journal Article {Title}: Mechanisms of Medial Wall Thinning in Chronic Total Occlusion. {Author}: Konishi T;Kawakami R;Vozenilek AE;Ghosh SKB;Xu W;Grogan A;Shah P;Tanaka T;Sekimoto T;Shiraki T;Kawai K;Sato Y;Mori M;Sakamoto A;Hisadome H;Ashida K;Bellissard A;Williams D;Dryanovski D;Kutys R;Cheng Q;Romero M;Chahal D;Virmani R;Finn AV; {Journal}: JACC Cardiovasc Interv {Volume}: 17 {Issue}: 14 {Year}: 2024 Jul 22 {Factor}: 11.075 {DOI}: 10.1016/j.jcin.2024.05.013 {Abstract}: BACKGROUND: The success rate of percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) is lower and the risk for complications higher compared with other non-CTO PCI. Although interventionalists focus on intimal plaque characteristics, the coronary media is an important (especially for techniques involving antegrade dissection and re-entry) but poorly understood structure in CTO PCI.
OBJECTIVE: The aim of the present study was to investigate coronary medial wall thinning in CTO lesions and determine how this thinning might affect CTO PCI.
METHODS: A total of 2,586 sections were investigated, from arteries with evidence of CTO from 54 subjects (1,383 sections) and arteries without evidence of CTO from 54 subjects with non-coronary-related deaths (1,203 sections) after matching for age, gender, body weight, and body height.
RESULTS: The medial thickness in subjects with CTO was lower than that in those with non-coronary-related death (P < 0.001). In subjects with CTO, CTO lesions had thinner medial walls compared with those with lower luminal narrowing (P < 0.001). At the CTO distal segments, the 6- to 12-mm distal segment from the distal end of the CTO had significantly less luminal narrowing (P < 0.001), and similar medial thickness, compared with the distal end of the CTO. Immunohistochemical analysis revealed that short-duration CTO had more cleaved caspase-3-positive cells in media and had significantly more CD3+, CD4+, CD8+, and CD4+CD28null T cells compared with long-duration CTO.
CONCLUSIONS: CTO lesions demonstrated coronary medial thinning compared with non-CTO lesions. Further investigation of the cause-and-effect relationship among inflammation, apoptosis, and coronary medial wall thinning is warranted in future mechanistic studies.