Sick sinus syndrome (SSS) is a set of diseases with abnormal cardiac pacing, which manifests as diverse cardiac arrhythmias, especially bradycardia. The clinical presentation is inconspicuous in the early stage, but with the progression of this disease, patients may present with symptoms and signs of end-organ hypoperfusion. As a common result in the natural history of the disease, SSS coexisting with atrial fibrillation (AF) forms the basis of bradycardia–tachycardia syndrome. Age-related interstitial fibrosis is considered to be the common pathophysiological mechanism between SSS and AF. The combination of these diseases will adversely affect the condition of patients and the efficiency of subsequent treatment. Although the exact mechanism is not clear to date, the extensive structural and electrical remodeling of the atrium are considered to be the important mechanism for the occurrence of AF in patients with SSS. Pacemaker implantation is the first-line treatment for symptomatic patients with SSS and documented bradycardia history. In view of the adverse effects of AF on the treatment of SSS, researchers have focused on evaluating different pacing modes and algorithms to reduce the risk of AF during pacing. Catheter ablation may also be used as an alternative second-line therapy for some patients with SSS and AF.

病态窦房结综合征（SSS）是一组心脏起搏异常的疾病，表现为多种心律失常，尤其是心动过缓。早期临床表现不明显，但随着疾病进展，患者可出现终末器官灌注不足的症状和体征。作为该疾病自然病程的常见结果，SSS 与心房颤动 (AF) 共存是心动过缓-心动过速综合征的基础。与年龄相关的间质纤维化被认为是 SSS 和 AF 之间常见的病理生理机制。这些疾病的组合会对患者的病情和后续治疗的效率产生不利影响。虽然目前还不清楚确切的机制，心房的广泛结构和电重构被认为是 SSS 患者发生 AF 的重要机制。起搏器植入是有症状且有心动过缓病史的 SSS 患者的一线治疗。鉴于 AF 对 SSS 治疗的不利影响，研究人员重点评估了不同的起搏模式和算法，以降低起搏过程中发生 AF 的风险。导管消融也可作为一些 SSS 和 AF 患者的替代二线治疗。研究人员专注于评估不同的起搏模式和算法，以降低起搏期间发生 AF 的风险。导管消融也可作为一些 SSS 和 AF 患者的替代二线治疗。研究人员专注于评估不同的起搏模式和算法，以降低起搏期间发生 AF 的风险。导管消融也可作为一些 SSS 和 AF 患者的替代二线治疗。