Implantable cardioverter-defibrillator utilization in coronary artery spasm: A case series of cardiac arrest survivors and a patient with typical angiography

Coronary artery spasm (CAS) can trigger severe angina pectoris, acute coronary syndrome, or sudden cardiac arrest (SCA). Calcium channel blockers and nitrates are recommended treatments, but the role of implantable cardioverter-defibrillators (ICDs) remains controversial. This study explored ICD application in CAS via a case series of cardiac arrest survivors and a patient with typical angiography findings. Four patients with recurrent angina (3 with prior cardiac arrest) were diagnosed with suspected or definite CAS based on predefined criteria and coronary angiography findings: transient ST-segment elevation, nitrate-responsive coronary narrowing, and no identifiable reversible triggers. Three patients with documented ventricular tachycardia/ventricular fibrillation (VT/VF) or SCA underwent ICD implantation, while the one without such history did not. During 3.6 ± 1.3 years of follow-up, all experienced recurrent angina (reduced by maximum-tolerated calcium antagonists plus long-acting nitrates). VT/VF events in two ICD recipients were successfully terminated by anti-tachycardia pacing or shocks. This case series confirms recurrent angina is common in CAS and highlights the efficacy of calcium antagonists and nitrates. ICD implantation may be warranted for CAS patients who survive VT/VF, a strategy supported by the literature. • Coronary artery spasm (CAS) can manifest not only as typical rest-related variant angina but also as exercise-induced episodes, and it may progress to life-threatening events such as ventricular tachycardia (VT), ventricular fibrillation (VF), or sudden cardiac death (SCA), even in the absence of severe fixed coronary stenosis. • Long-term administration of non-dihydropyridine calcium channel blockers combined with long-acting nitrates at maximum tolerated doses is effective in reducing the recurrence of angina pectoris in CAS patients. • For CAS patients who have survived sudden cardiac arrest or documented VT/VF, implantable cardioverter-defibrillator (ICD) implantation should be considered, as it can appropriately terminate recurrent life-threatening ventricular arrhythmias through anti-tachycardia pacing (ATP) or shocks.