Key result
Intracoronary nitrates and antithyroid therapy reverse thyrotoxicosis-induced coronary spasm presenting as cardiac arrest.
Why the study?
Cardiac arrest due to thyrotoxicosis-induced coronary artery spasm is exceedingly rare and requires early recognition for appropriate management.
Case Report (n=1)
Thyrotoxicosis-induced coronary artery spasm can present rarely as out-of-hospital cardiac arrest and is a reversible cause when managed promptly with antithyroid and vasodilator therapies.
Thyrotoxicosis-induced CAS can precipitate cardiac arrest; extends the arrhythmia differential but remains hypothesis-generating.
Background Cardiovascular manifestations of thyrotoxicosis are common, typically presenting as tachyarrhythmias or high-output physiology. Coronary artery spasm (CAS) is an uncommon but increasingly recognized complication, usually causing transient ischemia rather than malignant ventricular arrhythmias. Cardiac arrest due to thyrotoxicosis-induced CAS is exceedingly rare. Early recognition is vital because management differs from typical acute coronary syndromes (ACS). Case Summary A 63-year-old man suffered an out-of-hospital cardiac arrest with an initial shockable rhythm, achieving return of spontaneous circulation (ROSC) after a single defibrillation. Initial evaluation revealed inferior ST-segment elevation, leading to urgent coronary angiography, which demonstrated severe right coronary artery spasm that resolved after intracoronary nitrate administration. Laboratory studies confirmed significant hyperthyroidism, and recurrent ST-segment changes in the ICU further supported thyrotoxicosis-induced coronary artery spasm as the underlying mechanism. The patient made a full neurological and cardiac recovery following temperature management, intensification of antithyroid therapy, and vasodilator treatment. Discussion This case underscores an unusual presentation of cardiac arrest triggered by thyrotoxicosis-related coronary artery spasm in the absence of underlying coronary artery disease. Elevated thyroid hormone levels can impair endothelial function and heighten vascular smooth muscle reactivity, creating a predisposition to diffuse, therapy-resistant vasospasm. Recognizing this reversible yet potentially fatal condition is crucial, as prompt initiation of antithyroid therapy and vasodilators can rapidly alleviate ischemia and reduce the risk of recurrence. The favourable outcome in this patient illustrates how early identification of the underlying cause can guide swift and effective management.
No takes yet. Share an insight, caveat, or question.
Wauters et al. (2026) conducted a case report in Thyrotoxicosis-induced coronary artery spasm and cardiac arrest (n=1). Thyrotoxicosis-induced coronary artery spasm was evaluated on Neurological and cardiac recovery. In a 63-year-old man, thyrotoxicosis-induced coronary artery spasm presenting as cardiac arrest was successfully reversed with intracoronary nitrates and antithyroid therapy.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: