Nasir Ali Zagham, Jorgensen Drew
Internal Medicine Residency, Trinity Health Grand Rapids, Grand Rapids, Michigan, USA
Critical Care, Trinity Health Grand Rapids, Grand Rapids, Michigan, USA.
BMJ Case Rep. 2023 Mar 24;16(3):e254907. doi: 10.1136/bcr-2023-254907.
Severe acute hyponatraemia, defined as a sodium concentration of less than 120 mEq/L, typically manifests with neurological manifestations, resulting in obtundation, coma, seizures, respiratory arrest and death. It very rarely is arrhythmogenic, with a literature review revealing seven cases of hyponatraemia-associated atrioventricular (AV) block of various degrees, of which only three were described as having third-degree AV block. The higher-degree AV blocks typically occurred at sodium levels closer to 115 mEq/L. We present a case of severe acute hypo-osmolar hyponatraemia-induced third-degree AV block in a patient without any other risk factors or aetiologies who initially presented with subdural haematoma and developed refractory bradycardia during his admission. The patient's third-degree AV block completely resolved after correction of his sodium. This case highlights the importance of working up the cause of new-onset third-degree AV block and the consideration of rarer electrolyte derangements such as hyponatraemia as a potential cause.
严重急性低钠血症定义为血钠浓度低于120 mEq/L，通常表现为神经症状，可导致意识模糊、昏迷、癫痫发作、呼吸骤停及死亡。它极少引起心律失常，文献综述显示有7例不同程度的低钠血症相关性房室（AV）阻滞，其中仅3例被描述为三度AV阻滞。较高程度的AV阻滞通常发生在血钠水平接近115 mEq/L时。我们报告1例严重急性低渗性低钠血症诱发三度AV阻滞的病例，该患者无任何其他危险因素或病因，最初表现为硬膜下血肿，住院期间出现难治性心动过缓。患者的血钠纠正后，三度AV阻滞完全缓解。该病例强调了对新发三度AV阻滞病因进行检查的重要性，以及考虑将低钠血症等较罕见的电解质紊乱作为潜在病因的必要性。
