Coronary sinus as an anatomical landmark for atrial transseptal puncture

Abstract

Aim. The study of interatrial septum (IAS) and coronary sinus (CS) syntopia in patients with atrial fibrillation (AF), who subsequently underwent pulmonary vein isolation with a cryoballoon and the determination of anatomical landmarks for puncture of the IAS.Methods. The data of preoperative computed tomography of the heart of 25 consecutive patients with AF, who subsequently underwent pulmonary vein isolation with a cryoballoon, were analyzed. Angulations describing IAS orientation and CS direction were measured. The relationships between IAS orientation, CS direction and size of left atrium were subsequently analyzed.Results. The mean angulations for IAS orientation and CS direction were 47.2±7.8° (range 27.6 - 57.3) and 47.2±7.8° (range 26.7 - 59.3) respectively. On the conventional clock face (direction of the flag of the puncture needle), these values corresponded to the following time: 4 h 34 min±15 min (from 3 h 55 min to 4 h 55 min) for the IAS orientation and 4 h 31 min±16 min (from 3 h 53 min to 4 h 54 min) for the CS direction. Statistically significant correlation was revealed between the IAS orientation and the CS direction (r = 0.77; p <0.001). Linear regression analysis by the least squares method showed that the CS direction explains 60% of the observed variability in IAS orientation. The final regression equation for the relationship between the IAS orientation and the CS direction is presented as: IAS orientation = 12.76 + 0.75 × CS direction. Analysis of the relationship between the IAS orientation and the size of the left atrium did not reveal any significant correlation and dependence (p=0.84). All 25 patients who took part in the study underwent pulmonary vein isolation with a cryoballoon. Puncture of the IAS from the first time was successful in 100% of patients. In 24 patients (96%), it was possible to achieve grade 4 occlusion of the pulmonary veins, and a bidirectional block was confirmed when checking the electrical activity of PV. All cryoballoon ablation procedures were completed without complications.Conclusion. In patients with AF, the CS direction can be a reliable predictor of the IAS orientation, which can be used in clinical practice. However, to verify the data and determine technical recommendations for transseptal puncture, additional clinical studies are needed.