• atrial flutter;
  • catheter ablation;
  • cavotricuspid isthmus;
  • congenital heart disease

We report a 66-year-old woman with a history of multiple cerebral aneurysms, polysplenism, junctional rhythm, and recurrent deep venous thrombosis. She suffered a pulmonary embolus after undergoing surgical clipping of cerebral aneurysms and computed tomography imaging identified congenital absence of the right inferior vena cava with persistent left inferior vena cava and left superior vena cava. The patient was anticoagulated with warfarin with goal INR of 2–3.

Several years later she presented to our clinic with recurrent supraventricular tachycardia and 12-lead electrocardiogram consistent with “typical” cavotricuspid isthmus-dependent atrial flutter (Fig. 1A). After several cardioversions she elected to pursue an electrophysiology study and possible ablation.


Figure 1. For a high quality, full color version of this figure, please see Journal of Cardiovascular Electrophysiology's website:

Download figure to PowerPoint

Catheters were advanced via the femoral veins bilaterally through the persistent left inferior vena cava, hemiazygous, persistent left superior vena cava, and coronary sinus to the right atrium. Using a D-curve Thermocool™ SF catheter and CARTO III fast activation mapping (Biosense Webster, Diamond Bar, CA, USA), a 3-dimensional geometry of the left inferior vena cava, hemiazygous, left superior vena cava, coronary sinus, and right atrium (Fig. 1B) was created. Activation mapping of the tachycardia demonstrated reentry around the tricuspid annulus. There was no right inferior vena cava remnant to create a traditional line of ablation along the cavotricuspid isthmus. Instead, we performed a line of ablation connecting the tricuspid annulus to the coronary sinus in the area of the anatomical slow pathway. This line of ablation provided block along the tricuspid annulus and rendered the tachycardia noninducible.