A case report of cryoballoon-based pulmonary vein isolation in a patient with situs inversus abdominalis and levocardia

Background Cryoballoon-based pulmonary vein isolation (cbPVI) is a standardized treatment of atrial fibrillation. In complex anatomies, radiofrequency ablation (rfPVI) is usually preferred. We describe the first cbPVI in a rare patient with SI and levocardia. Case summary A 41-year-old male patient with paroxysmal atrial fibrillation was referred to our clinic after a previous, unsuccessful cbPVI procedure. Observation of an atypical lead-wire position due to an abnormal anatomy of the inferior vena cava led to its initial termination. A subsequent thoraco-abdominal computed tomography revealed situs inversus abdominalis and levocardia and the procedure was re-attempted in our clinic. Transseptal puncture (TSP) was guided via transoesophageal echocardiography and fluoroscopy, using a SL0-Sheath and a standard BRK-needle. Advancement of the sheath initially failed but after additional dilatation with an Inoue® dilator, transseptal passage of the sheath was successful. Due to the unusual antero-cranial TSP, the septal pulmonary veins (PV) contrasted poorly. After repeat TSP, a steerable FlexCath Advance® sheath was introduced into the left atrium using an Amplatz Super Stiff® guidewire. Subsequently, all PV were intubated with the Achieve® catheter, over which a 2nd generation cryoballoon was introduced. Despite the practical challenges in this case, all PV were isolated. Discussion The main challenges include the achievement of transseptal access and manipulation of the cryoballoon to achieve a patent seal of the pulmonary veins. cbPVI eliminates the need for constant re-positioning of the ablation catheter and might facilitate the creation of durable lesions under such difficult anatomical conditions.