Superior approach for radiofrequency ablation of atrio-ventricular nodal reentrant tachycardia in a patient with anomalous inferior vena cava and azygos continuation.

We present a 45-year-old woman with supraventricular tachycardia. During placement of diagnostic catheters, an interruption of the inferior vena cava was suspected. An MRI confirmed the interruption of the inferior vena cava above the level of the renal veins with azygos vein continuation up to the superior vena cava. Catheter ablation was performed using a superior approach via the left subclavian vein.