Peng Shengjia, Qi Yu, Sun Lijie, Li Dan, Wang Xinyu, Han Jiangli, Chen Baoxia, Zhang Yuan
Department of Cardiology, Peking University Third Hospital; Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptide, Ministry of Health, Beijing 100191, China.
Beijing Da Xue Xue Bao Yi Xue Ban. 2024 Apr 18;56(2):357-361. doi: 10.19723/j.issn.1671-167X.2024.02.025.
Afferent baroreflex failure (ABF) is a rare disease. It refers to the clinical syndrome caused by the impairment of the afferent limb of the baroreflex or its central connections at the level of the medulla. The recognized causes include trauma, surgery in related areas (radical neck tumor surgery, carotid endarterectomy), neck radiotherapy, brain stem stroke, tumor growth paraganglioma and hereditary diseases, among which the most common cause is extensive neck surgery or radiotherapy for neck cancer. The main manifestations are fluctuating hypertension, orthostatic hypotension, paroxysmal tachycardia and bradycardia. This case is a young man, whose main feature is blood pressure fluctuation, accom-panied by neurogenic orthostatic hypotension (nOH). After examination, the common causes of hypertension and nOH were ruled out. Combined with the previous neck radiotherapy and neck lymph node dissection, it was considered that the blood pressure regulation was abnormal due to the damage of carotid sinus baroreceptor after radiotherapy for nasopharyngeal carcinoma and neck lymph node dissection, which was called ABF. At the same time, the patient was complicated with chronic hyponatremia. Combined with clinical and laboratory examination, the final consideration was caused by syndrome of in- appropriate antidiuretic hormone (SIADH). Baroreceptors controlled the secretion of heart rate, blood pressure and antidiuretic hormone through the mandatory "inhibition" signal. We speculate that the carotid sinus baroreceptor was damaged after neck radiotherapy and surgery, which leads to abnormal blood pressure regulation and nOH, while the function of inhibiting ADH secretion was weakened, resulting in higher ADH than normal level and mild hyponatremia. The goal of treating ABF patients was to reduce the frequency and amplitude of sudden changes in blood pressure and heart rate, and to alleviate the onset of symptomatic hypotension. At present, drug treatment is still controversial, and non-drug treatment may alleviate some patients' symptoms, but long-term effective treatment still needs further study. The incidence of ABF is not high, but it may lead to serious cardiovascular and cerebrovascular events, and the mechanism involved is extremely complicated, and there are few related studies. The reports of relevant medical records warn that patients undergoing neck radiotherapy or surgery should minimize the da-mage to the baroreceptor in the carotid sinus in order to reduce the adverse prognosis caused by complications.
传入性压力感受器反射衰竭（ABF）是一种罕见疾病。它指的是由压力感受器反射的传入支或其在延髓水平的中枢连接受损所引起的临床综合征。公认的病因包括创伤、相关区域手术（根治性颈部肿瘤手术、颈动脉内膜切除术）、颈部放疗、脑干卒中、副神经节瘤生长及遗传性疾病等，其中最常见的病因是广泛的颈部手术或颈部癌症放疗。主要表现为血压波动、体位性低血压、阵发性心动过速和心动过缓。该病例为一名青年男性，其主要特征是血压波动，并伴有神经源性体位性低血压（nOH）。经检查，排除了高血压和nOH的常见病因。结合既往颈部放疗及颈部淋巴结清扫术，考虑为鼻咽癌放疗及颈部淋巴结清扫术后颈动脉窦压力感受器受损导致血压调节异常，即ABF。同时，该患者合并慢性低钠血症。结合临床及实验室检查，最终考虑是由抗利尿激素分泌不当综合征（SIADH）所致。压力感受器通过强制性“抑制”信号控制心率、血压及抗利尿激素的分泌。我们推测颈部放疗及手术后颈动脉窦压力感受器受损，导致血压调节异常及nOH，而抑制抗利尿激素分泌的功能减弱，致使抗利尿激素水平高于正常，进而出现轻度低钠血症。治疗ABF患者的目标是降低血压和心率突然变化的频率及幅度，缓解症状性低血压的发作。目前，药物治疗仍存在争议，非药物治疗可能会缓解部分患者的症状，但长期有效的治疗仍需进一步研究。ABF的发病率不高，但可能导致严重的心脑血管事件，且涉及的机制极其复杂，相关研究较少。相关病历报告警示，接受颈部放疗或手术的患者应尽量减少对颈动脉窦压力感受器的损伤，以降低并发症所致的不良预后。
