Itsuro Morishima

1 Introduction Sick sinus syndrome (SSS) and atrial fibrillation (AF) frequently coexist, reflecting a shared underlying atrial pathology rather than two independent disease entities. In this issue of the Journal of Cardiovascular Electrophysiology, Horie R et al. provide important insights into the procedural complexity and clinical outcomes of AF ablation in patients with SSS [1].

Conflicts of Interest The authors declare no conflicts of interest. Supporting Information Filename Description jce70257-sup-0001-Supplemental_material_R2.docx3.6 MB Figure 1: Atrial pacing at a constant rate. Figure 2: Ventricular rapid pacing. References 1, , , , , and , “Transcatheter Electrical Ablation of Right Bundle Branch. A Method of Treating Macroreentrant Ventricular Tachycardia Attributed to Bundle Branch Reentry,” Circulation 78 (1988): 246–257.

Background Acute total or subtotal occlusion of the unprotected left main coronary artery (ULMCA) is a rare but severe condition with high short-term mortality. However, the long-term prognosis of patients who survive to discharge after emergent percutaneous coronary intervention (PCI) remains unclear. This study aimed to evaluate long-term clinical outcomes in this population.