Background: coronary sinus ostial atresia (CSA) is a rare CS anomaly which may give rise to difficult mapping and ablation of Supraventricular tachyarrhythmias(SVA) owing to the lack of electrogram in CS catheter and the complicated anatomy.
Objective: To describe the anatomical and clinical features in patients combine with CSA and SVA.
Methods: 7,364 consecutive patients receiving electrophysiology procedures were retrospectively screened for CSA, whose clinical data, fluoroscopy and cardiac tomography were analyzed.
Results: Among 7 CSA patients (mean age 39.4±15.0 , 3 males):1 suffered acquired CSA due to the history of thoracotomy for single atrium while the others were congenital CSA. 57.1% (4/7) were combined with cardiac anomalies. Three types of CSA can be divided according to the cardiac venous reflux pathways (figure). A total of 8 arrhythmias induced during electrophysiology study including 2 atrioventricular nodal reentrant tachycardia (AVNRT), 2 atrial flutter (AFL), 1 paroxysmal atrial fibrillation (PAF) and 3 left accessory pathway(L-AP). A transseptal approach to place the decapolar catheter in LA performed in 2 patients for located the L-AP after the electrophysiology study. Ablation performed except for 1 PAF and 1 Intermittent pre-excitation. No procedure related complication happened during hospitalization. After a follow-up of 4.5 to 97.4 months, 4 patients free of SVA while 1 AFL relapsed.
Conclusion: CSA may complicate with different kinds of SVA. Electrophysiology procedure is safe and efficient in these patients. The differential diagnosis might be more challenging and an individualized mapping strategy base on the three types of CS reflux will be help.