ABSTRACT
BACKGROUND: Idiopathic left ventricular tachycardia (ILVT) is a rare but well-recognized clinical entity. The clinical characteristics and prognosis of this form of ventricular tachycardia (VT) in Thai children is not known. OBJECTIVE: To define clinical presentations, drug therapies, roles of radiofrequency (RF) catheter ablation, and the short-term outcome of these children in Thailand. PATIENTS AND METHOD: From April 1999 to June 2007, 10 patients were diagnosed as ILVT by specific electrocardiographic features and therapeutic response. All patients had a structurally normal heart. Data were collected retrospectively. Baseline clinical information, 12-lead electrocardiography (ECG) during VT, responses to drug therapy, results of RF catheter ablation therapy, and outcome were determined. RESULTS: Median age at presentation was 9.5 years (range, 3.8 to 14.0 years). Three patients (30%) were male. Eight patients (80%) were diagnosed as supraventricular tachycardia (SVT) before ILVT diagnosis. Median duration from SVT diagnosis to the correct diagnosis was 1.5 years (range, 0 to 6.0 years). Palpitation and chest pain were usual clinical manifestations while congestive heart failure was the presentation in one due to incessant tachycardia. Two patients had recurrent VT episodes during acute febrile illnesses. The majority of patients responded to intravenous verapamil. RF catheter ablation was performed in 3 patients with recurrence of the VT in one. CONCLUSION: Prompt recognition of the ILVTespecially in the emergency department is very important. Verapamil is effective for acute termination as well as prevention of VT recurrence. When VT is refractory to medical therapy, RF catheter ablation is safe and effective. The short-term prognosis was good.