Zero-Fluoroscopy Catheter Ablation for Cavo-Tricuspid Isthmus-Dependent Atrial Flutter in a Pregnant Patient with Congenital Heart Disease

Background:

Catheter ablation (CA) for atrial arrhythmias has demonstrated feasibility and safety with minimal radiation exposure largely due to the integration of three-dimensional (3D) anatomical mapping systems. The management of arrhythmias during pregnancy poses significant challenges as antiarrhythmic drugs frequently carry teratogenic risks, and ionizing radiation can adversely affect both the mother and fetus. Zero-fluoroscopy CA offers a promising alternative for treating arrhythmias in this patient population.

Case Presentation: 

We report the case of a 24-year-old pregnant woman with a Shone’s complex, a congenital heart disease with aortic valve and isthmus stenosis, a bypass from the ascending to descending aorta, pulmonary hypertension, and mitral valve replacement. The patient had two previous unsuccessful pregnancies and was advised against a new one. However, the patient became pregnant again and presented in her second trimester with palpitations. The ECG was suggestive of cavo-tricuspid isthmus (CTI)-dependent atrial flutter.  Due to the limited therapeutic options and the high risk of cardiac decompensation and complications as the pregnancy evolved, in agreement with the patient, we decided to perform a zero-fluoroscopy catheter ablation using entirely 3D mapping navigation.

After achieving vascular access, a steerable sensor-enabled coronary sinus (CS) decapolar catheter (Decanav, Biosense-Webster) was advanced into the inferior vena cava under the guidance of a 3D mapping system (CARTO, Biosense-Webster). With the aid of the catheter, we could obtain the anatomy of IVC, the right atrium, superior vena cava, and CTI. Then, we changed to a steerable long Agilis sheath, using an irrigated ablation catheter (Thermocool STSF, Biosense-Webster) instead of a guidewire to the advance the catheter into the right atrium. With the aid of the same catheter an electro-anatomical LAT map of the tachycardia was created which confirmed counter-clockwise typical atrial flutter. Ablation along the CTI was successfully performed without complications leading to arrhythmia termination. During a two-month follow-up period, the patient remained free of arrhythmia recurrence.

Conclusion:

This case highlights the safety and feasibility of zero-fluoroscopy CA using 3D anatomical mapping systems in conjunction with steerable, sensor-enabled catheters. Zero-fluoroscopy ablation represents a viable treatment option in cases where radiation exposure and/or antiarrhythmic drug therapy is contraindicated.