%0 Journal Article
%T Mechanisms of Medial Wall Thinning in Chronic Total Occlusion.
%A Konishi T
%A Kawakami R
%A Vozenilek AE
%A Ghosh SKB
%A Xu W
%A Grogan A
%A Shah P
%A Tanaka T
%A Sekimoto T
%A Shiraki T
%A Kawai K
%A Sato Y
%A Mori M
%A Sakamoto A
%A Hisadome H
%A Ashida K
%A Bellissard A
%A Williams D
%A Dryanovski D
%A Kutys R
%A Cheng Q
%A Romero M
%A Chahal D
%A Virmani R
%A Finn AV
%J JACC Cardiovasc Interv
%V 17
%N 14
%D 2024 Jul 22
%M 38970581
%F 11.075
%R 10.1016/j.jcin.2024.05.013
%X <B>BACKGROUND: </B>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.<BR><B>OBJECTIVE: </B>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.<BR><B>METHODS: </B>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.<BR><B>RESULTS: </B>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.<BR><B>CONCLUSIONS: </B>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.