Persistent Palpitations and Dyspnea in a Middle-aged Man

The patient routinely assesses his blood pressure and heart rate with the latter usually being 60-70 beats/min; he has noted his pulse to be persistently elevated in the 120s-130s.
The tracing from an ECG performed in the office is shown on next slide.

Based on your review of the ECG tracing and the patient’s clinical history, what is the most likely diagnosis?

A right atrial tachyarrhythmia is likely considering the patient’s history of ARPVR complicated by right-sided heart failure. Finally, a reentrant arrhythmia around the right atrial incision sites and scar from his prior cardiac surgery–an “incisional atrial flutter”-should be suspected.

The best next step in management of the patient is an invasive electrophysiology study during ongoing tachycardia. The study will identify the region of scar and propagation of arrhythmia for targeted ablation, with the result being restoration and long-term maintenance of sinus rhythm.

The voltage map showed a large no-signal area (gray areas above correlating to scar) along the entire lateral aspect of the right atrium corresponding to the atriotomy created for surgical repositioning of the right pulmonary veins from the right atrium to the left atrium. Activation mapping showed a large macroreentrant circuit with a clockwise pattern around this area of scar. A narrow region of intact voltage and slow conduction velocity was identified within the scar (purple area above) which served as the critical isthmus for propagation of the tachycardia circuit.

The patient has done well, remaining free of recurrent arrhythmia without medical therapy for more than 1 year since his ablation procedure.