Background and Aims Prior reports have demonstrated a favourable safety and efficacy profile of the Micra leadless pacemaker over mid-term follow-up; however, long-term outcomes in real-world clinical practice remain unknown. Updated performance of the Micra VR leadless pacemaker through five years from the worldwide post-approval registry (PAR) was assessed. Methods All Micra PAR patients undergoing implant attempts were included. Endpoints included system- or procedure-related major complications and system revision rate for any cause through 60 months post-implant. Rates were compared through 36 months post-implant to a reference dataset of 2667 transvenous pacemaker patients using Fine–Gray competing risk models. Results 1809 patients were enrolled between July 2015 and March 2018 and underwent implant attempts from 179 centres in 23 countries with a median follow-up period of 51.1 months (IQR: 21.6–64.2). The major complication rate at 60 months was 4.5% [95% confidence interval (CI): 3.6%–5.5%] and was 4.1% at 36 months, which was significantly lower than the 8.5% rate observed for transvenous systems (HR: .47, 95% CI: .36–.61; P < .001). The all-cause system revision rate at 60 months was 4.9% (95% CI: 3.9%–6.1%). System revisions among Micra patients were mostly for device upgrades (41.2%) or elevated thresholds (30.6%). There were no Micra removals due to infection noted over the duration of follow-up. At 36 months, the system revision rate was significantly lower with Micra vs. transvenous systems (3.2% vs. 6.6%, P < .001). Conclusions Long-term outcomes with the Micra leadless pacemaker continue to demonstrate low rates of major complications and system revisions and an extremely low incidence of infection.

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无引线起搏器 5 年随访：Micra 经导管起搏系统批准后登记

背景和目标 先前的报告已证明 Micra 无引线起搏器在中期随访中具有良好的安全性和有效性。然而，现实临床实践中的长期结果仍然未知。对 Micra VR 无引线起搏器五年内的最新性能进行了全球批准后注册 (PAR) 评估。方法 纳入所有尝试种植的 Micra PAR 患者。终点包括系统或手术相关的主要并发症以及植入后 60 个月内任何原因的系统修正率。使用 Fine-Gray 竞争风险模型将植入后 36 个月的比率与 2667 名经静脉起搏器患者的参考数据集进行比较。结果 2015 年 7 月至 2018 年 3 月期间纳入了 1809 名患者，并在 23 个国家的 179 个中心接受了种植尝试，中位随访期为 51.1 个月（IQR：21.6-64.2）。60 个月时的主要并发症发生率为 4.5% [95% 置信区间 (CI)：3.6%–5.5%]，36 个月时的主要并发症发生率为 4.1%，显着低于经静脉系统观察到的 8.5% 发生率（HR：. 47，95% CI：0.36–0.61；P < 0.001）。60 个月时的全因系统修正率为 4.9%（95% CI：3.9%–6.1%）。Micra 患者的系统修改主要是为了设备升级（41.2%）或提高阈值（30.6%）。在随访期间没有发现因感染而移除 Micra 的情况。36 个月时，Micra 的系统修正率明显低于经静脉系统（3.2% vs. 6.6%，P < .001）。结论 Micra 无引线起搏器的长期结果继续表明主要并发症和系统修复发生率较低，感染发生率极低。