Meyers Michael, Balf Dragos, Raza Mohammad Q, Liu Xiaoke
Mayo Clinic Health System, 800 West Ave. S, La Crosse, WI 54601, USA.
Mayo Clinic, 200 1st St SW, Rochester, MN 55905, USA.
Eur Heart J Case Rep. 2024 Nov 15;8(11):ytae579. doi: 10.1093/ehjcr/ytae579. eCollection 2024 Nov.
Optimal management of checkpoint inhibitor-induced complete heart block is unknown. Previous reports showed relatively high incidence of pacing failure due to the co-existing myocarditis.
A 71-year-old male with a prior history of stage IV metastatic squamous cell lung cancer presents was admitted for dyspnoea and hypotension 10 days after checkpoint inhibitor treatment using pembrolizumab. He was found to have myocarditis, third-degree AV block, severe left ventricular systolic dysfunction with EF 35%, and required pressure support. A dual chamber pacemaker using left bundle branch area pacing (LBBAP) was urgently placed that immediately improved his haemodynamics. Both the cathode and anode were able to capture the ventricle at different pacing outputs. The patient was taken off all intravenous pressors and successfully transferred to a larger centre for further management of the myocarditis with no further arrhythmia or hypotension.
In conclusion, because of the unique ability to capture a large amount of myocardium from both the tip and ring electrodes as well as the ability to deliver cardiac resynchronization therapy, LBBAP may be the preferred pacing strategy in patients who develop complete heart block due to checkpoint inhibitor-induced myocarditis.
检查点抑制剂诱发的完全性心脏传导阻滞的最佳管理方法尚不清楚。既往报告显示，由于并存心肌炎，起搏失败的发生率相对较高。
一名71岁男性，既往有IV期转移性鳞状细胞肺癌病史，在使用帕博利珠单抗进行检查点抑制剂治疗10天后，因呼吸困难和低血压入院。他被发现患有心肌炎、三度房室传导阻滞、严重左心室收缩功能障碍，射血分数为35%，需要压力支持。紧急植入了一台采用左束支区域起搏（LBBAP）的双腔起搏器，这立即改善了他的血流动力学。阴极和阳极在不同的起搏输出下均能夺获心室。患者停用了所有静脉升压药，并成功转至更大的中心进一步治疗心肌炎，未再出现心律失常或低血压。
总之，由于LBBAP的尖端和环状电极均具有独特的能够夺获大量心肌的能力以及进行心脏再同步治疗的能力，对于因检查点抑制剂诱发的心肌炎而发生完全性心脏传导阻滞的患者，LBBAP可能是首选的起搏策略。
