Aims: We aimed to evaluate the influence of ostial lesions on the predicted probability of success in patients undergoing percutaneous coronary interventions (PCIs) for chronic total occlusions (CTOs).

Methods: 245 consecutive patients who underwent CTO PCIs at Coburg Hospital, Coburg, Germany between 2017 and 2023 were included. Patients with and without ostial lesions were compared. Logistic regression models were used to estimate the potential of ostial lesion as additional predictor for success beside J-Score.

Results: 245 patients were included. Of those, 48 Patients (19.6%) had ostial lesions. The ostial lesion group exhibited significantly higher pro-B-type natriuretic peptide levels (1644 pg./ml vs. 963 pg./ml, p=0.034) than the non-ostial lesion group. The final success rate was lower in the ostial lesion group than in the non-ostial lesion group (64.6% vs.81.7%, p=0.018). The ostial lesion group had higher J-scores than the non-ostial lesion group, indicating more complex lesions (median: 2.5 vs. 2.0, p=0.005). Antegrade access was more applied in non-ostial lesion group (89.8% vs. 68.8% p=0.001), whereas retrograde access was more applied in ostial lesion group. (33.3% vs. 7.6%, p=0.003). Conclusion: The presence of ostial CTO is associated with higher lesion complexity and lower technical and procedural success rates. Presence of ostial CTO might be included as an additional factor in the currently used CTO scores to predict the difficulty and success rate of CTO procedure.

Keywords: Chronic Total Occlusion, Percutaneous Coronary Intervention, Ostial Lesions, Risk Prediction