Ventricular Pacing in Pacemaker Bigeminy to Rule in/out Truncated Pacemaker-mediated Tachycardia

Pacemaker bigeminy is not an uncommon electrocardiographic finding in device clinics. However, such a pattern mandates the differentiation of important possible diagnostic considerations such as premature atrial contractions, oversensing the T wave or the QRS complex, dual AV nodal physiology, and retrograde atrial depolarization. We present a case of pacemaker bigeminy where ventricular pacing was used to exclude the truncated form of pacemaker-mediated tachycardia and reach a diagnosis of atrial bigeminy, which was crucial from the management’s perspective.