Su Lina, Liu Chuanfen, Wu Wenjie, Cui Yuxia, Wu Manyan, Chen Hong
Department of Cardiology, Peking University People's Hospital, Beijing, China.
Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, Beijing, China.
Front Cardiovasc Med. 2022 May 12;9:898756. doi: 10.3389/fcvm.2022.898756. eCollection 2022.
Immune checkpoint inhibitors (ICIs) have revolutionized cancer therapy over the past decade. Despite their beneficial effects on treating numerous types of tumors, cardiotoxicity resulting from ICIs is a rare side effect but a concerning one due to its high mortality rate. We herein describe a case of an 80-year-old woman with recurrent head and neck squamous cell cancer (HNSCC), who presented with myocarditis complicated by complete atrioventricular block (CAVB) after second infusion of pembrolizumab. After quickly ruling out myocardial infarction and viral myocarditis, the strong relationship between the onset time and pembrolizumab therapy suggested that ICI-induced myocarditis was the most possible diagnosis. Though CAVB frequently presents with fulminant myocarditis in the setting of ICI-related cardiotoxicity, the patients kept a stable hemodynamic status and had normal myocardial function with just a slightly low global longitudinal strain (GLS) at-16.4%, which implied myocardial injury but was highly related to good prognosis based on the existing literature. Besides, elderly patients are vulnerable to adverse outcomes of steroid therapy, notably opportunistic infections. To balance beneficial effects and adverse effects of immune suppression, she accepted high-dose steroids without pulse methylprednisolone. Excitingly, she had a dramatic clinical and laboratory improvement, and heart block quickly returned to normal sinus rhythm. Another interesting finding was that the patient's tumor remained stable during the half-year follow-up from the termination of immunotherapy. Besides, we here firstly review previously reported cases in terms of their clinical characteristics and prognosis of ICI-induced myocarditis with CAVB, in particular the reversibility of heart block. In conclusion, ICI-induced myocarditis can be life-threatening and it therefore warrants efforts to increase awareness, facilitate early detection, and initiate prompt intervention. Importantly, CAVB secondary to ICIs-induced myocarditis may not always present with fulminant myocarditis and more than 50% of these surviving patients might recover to normal sinus rhythm. For patients with ICI-induced myocarditis with contraindication for cardiac magnetic resonance (CMR), speckle-tracking echocardiography is a reliable and sensitive alternative to CMR for detecting myocardial injury, and GLS may be an important prognostic indicator.
免疫检查点抑制剂（ICIs）在过去十年中彻底改变了癌症治疗方式。尽管它们对多种类型肿瘤的治疗具有有益效果，但ICIs导致的心脏毒性是一种罕见的副作用，因其高死亡率而令人担忧。我们在此描述一例80岁复发性头颈部鳞状细胞癌（HNSCC）女性患者，她在第二次输注帕博利珠单抗后出现心肌炎并并发完全性房室传导阻滞（CAVB）。在迅速排除心肌梗死和病毒性心肌炎后，发病时间与帕博利珠单抗治疗之间的密切关系表明，ICI诱导的心肌炎是最可能的诊断。尽管在ICI相关心脏毒性情况下，CAVB常伴有暴发性心肌炎，但患者血流动力学状态保持稳定，心肌功能正常，仅整体纵向应变（GLS）略低，为-16.4%，这意味着心肌损伤，但根据现有文献，这与良好预后高度相关。此外，老年患者易发生类固醇治疗的不良后果，尤其是机会性感染。为平衡免疫抑制的有益效果和不良效果，她接受了高剂量类固醇治疗，未使用脉冲甲基强的松龙。令人兴奋的是，她在临床和实验室检查方面有显著改善，心脏传导阻滞迅速恢复为正常窦性心律。另一个有趣的发现是，在免疫治疗终止后的半年随访期间，患者的肿瘤保持稳定。此外，我们在此首先根据先前报道的病例，对ICI诱导的心肌炎合并CAVB的临床特征和预后进行综述，特别是心脏传导阻滞的可逆性。总之，ICI诱导的心肌炎可能危及生命，因此有必要努力提高认识、促进早期检测并启动及时干预。重要的是，ICI诱导的心肌炎继发的CAVB可能并不总是伴有暴发性心肌炎，这些存活患者中超过50%可能恢复为正常窦性心律。对于有心脏磁共振成像（CMR）禁忌证的ICI诱导的心肌炎患者，斑点追踪超声心动图是检测心肌损伤的一种可靠且敏感的替代CMR的方法，GLS可能是一个重要的预后指标。
