A computed tomography (CT) simulation of transcatheter aortic valve replacement (TAVR) procedures concludes that the incidence of coronary overlap with transcatheter heart valve commissure is rare when commissural alignment is used. These findings were reported by Manish Vinayak, MD, and Gilbert H. L. Tang, MD, MSc, MBA, both of the Mount Sinai Health System, New York, and colleagues from the U.S. and Australia, in a manuscript published Wednesday online in JACC: Cardiovascular Interventions. TAVR is well-established as a treatment for severe aortic stenosis (AS) in patients in varying surgical risk categories. Coronary access post-TAVR depends on several factors, of which commissural alignment has become an important component. Coronary alignment has been proposed as an alternative to commissural alignment to reduce coronary overlap during TAVR, but more large-scale data are needed. The investigators in this study sought to find out how much coronary overlap occurred in patients receiving commissural versus coronary alignment using CT simulation in patients who were being evaluated for TAVR. A total of 1,851 CT scans (mean age=79.94 years, 55.8% male) were performed on native AS patients who were undergoing evaluation for TAVR between April 2018 and December 2022. Superimposable axial root images of the virtual valves simulating commissural and coronary alignment were assessed. Coronary overlap was measured based on the angular gap between coronary artery origin and the closest transcatheter heart valve commissure. Categories of coronary overlap included severe (≤15˚), moderate (15˚-30˚), mild (30˚-45˚) and no-overlap (45˚-60˚). Moderate or severe coronary overlap remained rare with either coronary artery or commissural alignment (coronary 0.52% left, 0.52% right; commissural 0.30% left, 3.27% right). In comparison, coronary alignment decreased the moderate or severe overlap for the right coronary artery only (0.38% versus 2.97%; p<0.0001). In the left coronary artery, both coronary and commissural techniques demonstrated moderate or severe overlap, but no-overlap rates were significantly higher in the commissural alignment group (91.1% versus 84.9%; p<0.0001). A strong correlation between commissural and coronary alignment was observed by the fluoroscopic angle during valve deployment as well (r=0.80; p<0.001). The authors noted that the coronary alignment evaluations were hypothetical and based on CT simulations and that they may not be accurate because of individual patient or procedural factors. They also noted as a limitation that patients with type 0 bicuspid anatomy were excluded from the study. They added that current THVs are not able to be rotated in reality to the degree they can be virtually, which might mean the virtual alignment does not accurately state the overlap risk in reality. The authors also acknowledged that short- and long-term clinical outcomes were not evaluated. Overall, using CT simulation, severe overlap of the transcatheter heart valve commissure to coronary in TAVR is rare with commissural alignment, but the coronary alignment technique decreases rates of moderate-severe coronary overlap in the right coronary artery only. The investigators in this study recommend coronary alignment only be used in exceptional cases where coronary overlap is predicted with commissural alignment. In an accompanying editorial, Didier Tchétché, MD, and Vincenzo Cesario, MD, of the Groupe CardioVasculaire Interventionnel, Toulouse, France, discussed a brief history of TAVR and improved outcomes for AS patients. They also wrote about the differences in data between coronary and commissural alignment. The editorialists wrote, “The main findings from this study are very interesting and meaningful for our daily practice.” Tchétché and Cesario, who is also affiliated with Sapienza University of Rome, presented two follow-up questions for this study: “How reproducible is it in contemporary practice? and What is its true effect on coronary cannulation?” They then proposed how the field can address these questions in future studies. “What we could expect in the future, apart from academic studies with greater sample size and/or a randomized design to validate the findings from both studies presented in this issue of the journal, are new-generation TAVR devices with active and consistent clocking features to achieve predictable commissural alignment,” the editorialists wrote, referring both to the study by Vinayak, Tang et al. and the RE-ACCESS 2 study, which was also published online Wednesday in JACC: Cardiovascular Interventions. Sources: Vinayak M, Tang GHL, Li K, et al. Commissural vs Coronary Alignment to Avoid Coronary Overlap With THV-Commissure in TAVR: A CT-Simulation Study. JACC: Cardiovasc Interv. 2024 Mar 6 (Article in Press). Tchétché D, Cesario V. Commissural and Coronary Alignment Techniques: It Is All Right! JACC Cardiovasc Interv. 2024 Mar 6 (Article in Press). Image Credit: Dusit – stock.adobe.com