Adenosine triphosphate-induced life-threatening arrhythmia.

UNLABELLED: A 68-year-old woman with idiopathic dilated cardiomyopathy presented with a wide QRS complex regular tachycardia five days after mitral valve replacement. Adenosine triphosphate (ATP) was administered to make the correct diagnosis; however, tachycardia eventually transitioned to ventricular fibrillation, which required cardioversion. Although ATP is considered a relatively safe drug, it can cause unexpected, life-threatening arrhythmias. Careful monitoring and preparation are advised during ATP administration in the event of a regular wide QRS complex tachycardia in patients with irritable conditions.

LEARNING OBJECTIVE: Adenosine triphosphate (ATP) is considered a safe drug that is often used to manage wide QRS complex tachycardia. Herein, we present a case of regular, wide QRS complex tachycardia in a patient who underwent mitral valve replacement. Tachycardia degenerated into ventricular fibrillation soon after ATP administration, probably because of sympathetic overdrive secondary to the ATP infusion. It is advisable to use ATP with caution, especially in irritable cases such as in the early post-cardiac surgery period.