Reversible tachycardia mediated cardiomyopathy after radiofrequency ablation of idiopathic left ventricular tachycardia

Abstract

A 20-year-old girl was admitted to our hospital with a chief complain of 12-days of palpitation and progressive shortness of breath. The symptoms of heart failure were consistent with New York Heart Association (NYHA) grade III. She had fever and cold symptoms 2-days before the onset of palpitation and heart failure symptoms but recovered soon, without other significant medical history. Physical examination demonstrates a heart rate of 170 beats per minute (bpm), a blood pressure of 70/40 mm Hg and bibasilar rales. ECG revealed a relatively narrow QRS tachycardia of 170 bpm with right bundle branch block (RBBB) morphology and a superior left axis configuration (Fig. 1a ). At the emergency department, empirical administration of intravenous verapamil was implemented and sinus rhythm was restored within 3 min with inverted T wave in leads II, III, aVF and V3–6 (Fig. 1b). A chest X-ray revealed bilateral plural effusion and increased cardiothoracic ratio (Fig. 2a ). Transthoracic echocardiography performed demonstrated marginal left ventricular dysfunction (left ventricular ejection fraction [LVEF] of 50%), with a normal LV end-diastolic diameter (LVEDD) of 38 mm and cardiac effusion with a fluid sonolucent area of 6 mm. Electrophysiological study performed in the following day after administration induced narrow QRS tachycardia which did not replicate the clinical morphology and indicated atrio-ventricular tachycardia via left atrio-ventricular bypass (Fig. 3a ), while the tachycardia of clinical morphology was not induced. The atrio-ventricular bypass was successfully ablated and the pre-systolic Purkinje potentials (Fig. 3b) were targeted, resulting in a new Q wave in inferior leads of ECG which mimics left posterior fascicular block after ablation (Fig. 1c). Chest X-ray performed in the 2nd day (Fig. 2b), the 3rd day (Fig. 2c) and the 40th day (Fig. 2d) revealed decreased and demission of plural effusion and decrease cardiothoracic ratio. Transthoracic echocardiography performed in the 3rd day demonstrated normalization of left ventricular dysfunction (LVEF of 76.6%) and cardiac effusion with a fluid sonolucent area of 6 mm, while in the 40th day the cardiac effusion was diminished. ECG in the 40th day revealed T wave restored upright (Fig. 1d). The patient remained free from arrhythmia for 2 months, without anti-arrhythmic medication.