Coexistence of Atrial Flutter and Slow Ventricular Tachycardia: A Rare Cause of Reversible Cardiomyopathy

Dual tachycardia, the rare coexistence of supraventricular tachycardia (SVT) and ventricular tachycardia (VT), is often challenging to diagnose, particularly when SVT with bundle branch block obscures VT signs and especially without clear atrioventricular dissociation.

A 55-year-old man with a history of hypertension presented with chest tightness, dyspnea, and transient syncope. Initially misdiagnosed as having atrial flutter with ventricular aberrancy via electrocardiogram, the patient was ultimately confirmed through electrophysiological testing to have atrial flutter coexisting with slow VT originating from the right midventricular septum along the right bundle branch. He underwent successful radiofrequency ablation.

Coexisting SVT and VT are frequently misdiagnosed, especially with proximal conduction abnormalities, increasing the risk of delayed recognition of tachycardia-induced cardiomyopathy.

This case highlights the importance of recognizing reversible cardiac dysfunction caused by dual tachycardia. Early rhythm control is key to improving prognosis.