The quality of the distal vessel should be taken into account when planning and performing chronic total occlusion (CTO) percutaneous coronary intervention (PCI), according to new multinational registry data. The study, published online Monday and in the June 26 issue of JACC: Cardiovascular Interventions, reports an association between poor-quality distal vessel and higher lesion complexity, higher need for retrograde crossing, lower technical and procedural success, higher incidence of MACE and coronary perforation, and higher radiation dose. Led by Salman S. Allana, MD, from the Minneapolis Heart Institute and Minneapolis Heart Institute Foundation at Abbott Northwestern Hospital, Minneapolis, the team behind the registry study noted that despite being an important variable in the hybrid and global CTO crossing algorithms, there are limited data on the impact of poor-quality distal target vessel on procedural techniques and outcomes on CTO PCI. “To the best of our knowledge, this study is the largest to date evaluating outcomes of CTO PCI in lesions with a poor-quality distal vessel,” said the authors. “Distal vessel quality should be strongly taken into account when planning and performing CTO PCI,” they warned. Study setup Allana and colleagues analyzed the baseline clinical and angiographic characteristics and procedural outcomes of 10,028 CTO PCIs performed in 9,836 patients at 39 U.S. and non-U.S. (Canada, Egypt, Greece, Russia, and Turkey) centers between 2012 and 2022 (192 patients underwent PCI of more than one CTO lesion). Coronary CTOs were defined as coronary lesions with Thrombolysis In Myocardial Infarction (TIMI) flow grade 0 of at least 3 months in duration, they said, adding that estimation of the duration of occlusion was clinical; based on the first onset of angina, prior history of myocardial infarction (MI) in the target vessel territory or comparison with a prior angiogram. A poor-quality distal vessel was defined as <2 mm diameter or with significant diffuse atherosclerotic disease, while in-hospital major adverse cardiac events (MACE) included death, myocardial infarction, urgent repeat target vessel revascularization, tamponade requiring pericardiocentesis or surgery, and stroke. “Compared with patients with a good-quality distal vessel, patients with a poor-quality distal vessel were more likely to have had prior PCI, prior CABG, diabetes mellitus, hypertension, dyslipidemia, prior MI, cerebrovascular disease, history of congestive heart failure, and peripheral arterial disease, and also had slightly lower left ventricular ejection fraction,” said the authors. Key findings The team reported that a total of 33% of all CTO lesions had poor-quality distal vessels, noting that the left anterior descending artery was less often (23.6% vs 27.2%; P < 0.001) and the left circumflex artery more often (21.5% vs 17.9%; P < 0.001) the target vessel in CTO lesions with a poor-quality distal vessel. When compared with CTO lesions with good distal vessel quality, lesions with a poor-quality distal vessel were more complex with higher J-CTO (2.7 ± 1.1 vs 2.2 ± 1.3; P < 0.001) and PROGRESS-CTO scores (1.2 ± 1.0 vs 1.5 ± 1.0; P < 0.001), higher prevalence of moderate-to-severe calcification (51.4% vs 40.9%; P < 0.001), proximal cap ambiguity (40.7% vs 31.7%; P < 0.001), blunt or no stump (59.3% vs 48.5%; P < 0.001), longer occlusion length (27.4 ± 18.5 mm vs 36.1 ± 23.4 mm; P < 0.001), and smaller proximal target vessel diameter (2.8 ± 0.6 mm vs 3.0 ± 2.9 mm; P < 0.001). Lesions with a poor-quality distal vessel also had lower technical success (79.9% vs 86.9%; P < 0.001) and procedural success (78.0% vs 86.8%; P < 0.001), and higher incidence of MACE (2.5% vs 1.7%; P = 0.01) and perforation (6.4% vs 3.7%; P < 0.001), said the team, adding that these lesions also required more stents (2 [interquartile range - IQR: 2-3] vs 2 [IQR: 1-3]; P < 0.001). Furthermore, in propensity score analysis that matched patients using 25 variables, a poor-quality distal vessel was associated with lower technical success (odds ratio [OR]: 0.78; 95% confidence interval [CI]: 0.69-0.89; P < 0.001) and higher in-hospital MACE (OR: 1.41; 95% CI: 1.01-1.96; P = 0.047). Finally, more patients with a poor-quality distal vessel received stents <2.5 mm in diameter (21.0% vs 13.3%; P < 0.001), said the team, noting that in-hospital MACE was higher in the group in which the smallest stent diameter used was <2.5 mm vs in the groups when the smallest stent diameter was 2.5 to 2.99 mm and ≥3 mm (2.2% vs 0.8% vs 1.6%; P = 0.01) Allana and colleagues concluded that CTOs with a poor-quality distal vessel are associated with higher lesion complexity, lower technical and procedural success rates, higher in-hospital MACE, higher rates of coronary perforation and donor vessel injury, more frequent use of the retrograde approach less frequent use of ADR as the successful crossing strategy; and longer procedure time and radiation dose. “Distal vessel quality should be strongly taken into account when planning and performing CTO PCI,” said the team, adding that additional studies with long term follow up are now also needed to assess long term outcomes of CTO PCI in patients with poor quality distal target vessel. Source: Allana SS, Kostantinis S, Simsek B, et al. Distal Target Vessel Quality and Outcomes of Chronic Total Occlusion Percutaneous Coronary Intervention. JACC Cardiovasc Interv 2023;16:1490-1500. Image Credit: Belezapoy – stock.adobe.com