Case 4
A 2-month-old girl with 6 kg of body weight was referred to our clinic with the diagnosis of tachycardia-induced cardiomyopathy. Electrocardiogram revealed long RP tachycardia with deep inverted P waves inferior leads. Echocardiography revealed a global dilatation of left ventricle (left ventricle end diastolic dimension of 36 mm, z score +4,3) with severe dysfunction of left ventricle (ejection fraction of 37%). A quadripolar catheter (Esolo FIAB, Italy) was inserted into esophagus as a reference catheter. Right atrial anatomy was mapped with Marinr TM CS Steerable Decapolar catheter (Medtronic, Inc., Minneapo­lis, MN, USA). During the procedure, long RP tachycardia was observed in the patient with negative P waves in the inferior leads. Pacing maneuvers revealed tachycardia mechanism as atypical AVNRT. Upon this, the activation mapping was obtained from earliest atrial activations during tachycardia, and ablation was performed in the posterior region of the right atrium near the entry of the coronary sinus with power of 30 W and 50oC temperature for 110 seconds. Tachycardia was terminated with accelerated junctional rhythm. On follow-up echocardiography, left ventricular systolic function has been improved. She is symptom-free for 2 years.