Sinus Node Dysfunction due to Occlusion of the Sinus Node Artery during Percutaneous Coronary Intervention

Background. Sinus node artery occlusion (SNO) is a rare complication of percutaneous coronary intervention (PCI). We analyze both the short- and long-term consequences of SNO. Methods. We retrospectively reviewed 1379 consecutive PCI’s involving RCA and Cx arteries performed in our heart institute from 2016 to 2019. Median follow-up was 44 ± 5 months. Results. Among the 4844 PCIs performed during the study period, 284 involved the RCA and the circumflex’s proximal segment. Periprocedural SNO was estimated by angiography observed in 15 patients (5.3%), all originated from RCA. The majority of SNO occurred during urgent and primary PCIs following acute coronary syndrome (ACS). Sinus node dysfunction (SND) appeared in 12 (80%) of patients. Four (26.6%) patients had sinus bradycardia, which resolved spontaneously, and 8 (53.3%) patients had sinus arrest with an escaped nodal rhythm, which mostly responded to medical treatment during the first 24 hours. There was no association between PCI technique and outcome. Three patients (20%) required urgent temporary ventricular pacing. One patient had permanent pacemaker implantation. Pacemaker interrogation during follow-up revealed a recovery of the sinus node function after one month. Conclusion. SNO is rare and seen mostly during angioplasty to the proximal segment of the RCA during ACS. The risk of developing sinus node dysfunction following SNO is high. SND usually appears during the first 24 h of PCI. The majority of SND patients responded to medical treatment, and only in rare cases were permanent pacemakers required.

6120Anatomical investigation of the sinus node artery and the radiofrequency application sites for catheter ablation of atrial fibrillation

Background Circumferential pulmonary vein isolation is an established therapy for selected patients with atrial fibrillation (AF). Three-dimensional imaging modalities can be useful to establish the mechanism of a procedure-related complication. Purpose The purpose of this study was to investigate the course of the sinus node artery (SNA) and the coronary arterial injury during catheter ablation of AF. Methods In the 254 consecutive patients, the courses of the SNA were recorded using multislice computed tomography. Results The visualization rate was 96.9% (246/254). Of 246 patients, 287 SNAs were detected among which 114 (44.9%) originated from the right coronary artery, 91 (35.9%) from the left circumflex (Cx) artery, and 41 (16.1%) from both the right and Cx artery. Only SNAs originated from the Cx artery coursed along the left atrium. Only in 2 patients, SNAs coursed endocardial surface of the left atrium. In one of these 2 patients, sinus node dysfunction developed just after the ablation of the right superior pulmonary vein ostium, requiring a permanent pacemaker implantation. The SNA originated from the distal Cx artery, and precisely coursed endocardial surface at the radiofrequency application site. Coronary angiography revealed the occlusion of the SNA at that site, and the SNA occlusion was presumed the cause of the sinus node dysfunction in this patient. Conclusion The recognition of the course of the SNA is important in minimizing the risk of sinus node dysfunction during catheter ablation of AF.

Transient sinus arrest due to sinus node artery thrombus after revascularisation of the left circumflex artery

We present a case of sinus arrest and junctional escape rhythm from sinus node artery (SNA) thrombus in a 55-year-old man after revascularisation of right coronary and proximal circumflex arteries for infero-posterior wall ST-segement elevation myocardial infarction (STEMI). Sinus arrest from occlusion of the SNA is uncommon. The ensuing bradycardia may have haemodynamic consequences requiring temporary pacing but is almost always self-limited.