Objective To evaluate the coronary artery ostium obstruction caused by the commissure of transcatheter heart valve (THV) with the markers on THV under X-ray, which was identified by observing the position relationship between the commissure of THV and the coronary artery ostium from analyzing aortic root computed tomographic angiography (CTA) images after transcatheter aortic valve replacement (TAVR). Methods A retrospective analysis was performed on 25 patients undergoing TAVR who were checked with electrocardiographically gated CTA for the aortic root after the TAVR procedure between January 2020 and December 2021 in General Hospital of Northern Theater Command. The images of THV with the lowest position of non-coronary sinus and the right anterior oblique and caudal in most cases were observed when the THVs were deployed. The position relationships of the three markers on the THV after valve release were recorded, which were divided into three conditions, namely the three markers being averagely distributed, the middle marker being close to left, and the middle marker being close to right. Postoperative CTA images of the patients were analyzed. The angle between the commissure of THV and the coronary artery ostium was measured, and the angles in each group were presented as medium (lower quartile, upper quartile). Results A total of 17 patients were finally included. The angles between the commissure of THV and the left coronary artery ostium were 19.0 (16.0, 31.0)°, 36.0 (15.0, 44.0)°, and 3.0 (3.0, 5.0)° in the markers averagely distributed group (n=7), the middle marker close to left group (n=6), and the middle marker close to right group (n=4), respectively, which were significantly different (P=0.033). The angles between the commissure of THV and the right coronary artery ostium were 43.0 (25.0, 51.0)°, 47.0 (41.0, 57.0)°, and 13.0 (7.5, 21.0)° in the markers averagely distributed group, the middle marker close to left group, and the middle marker close to right group, respectively, which were significantly different (P=0.017). There was significant difference in the obstruction degrees of left coronary artery ostium by the commissure of THV (P=0.008), and no significant difference in the obstruction degrees of right coronary artery ostium (P=0.062). When the middle marker was close to right, there was no more than moderately obstruction on the right coronary artery ostium and no any obstruction on the left coronary artery ostium. When the middle marker was close to left, the obstruction rate of the left coronary artery ostium with more than moderate degree was 4/6 (66.7%) and it was 6/6 (100.0%) for the right coronary artery ostium. Conclusions The degree of coronary artery ostium obstruction by the commissure of THV can be accurately evaluated by using markers on THV. Among them, when the middle marker is close to right, the commissures of THV are least likely to block the coronary artery ostium.