A Case of Epicardial Ablation of the Sinus Node for the Treatment of Inappropriate Sinus Tachycardia.

Despite advancements in medical therapy, managing symptomatic inappropriate sinus tachycardia (IST) remains challenging. The role of catheter ablation in addressing this condition remains ambiguous according to multiple cardiac society guidelines. In this case study, we illustrate the efficacy of a hybrid approach involving sinus node modification and ablation in a patient with refractory symptoms, while also addressing the associated challenges and safety considerations of this procedure. A 58-year-old female patient was troubled with recurrent palpitations secondary to IST. Due to the proximity of the target ablation site to the phrenic nerve, this area was not amenable to complete ablation endocardially. To alleviate symptoms, an ablation procedure was planned, aiming for epicardial sinus node modification and displacement of the phrenic nerve from the target site. The procedure was completed under general anesthesia. The conventional subxiphoid technique was deemed challenging even with a surgical approach due to the patient's body habitus and significantly increased body mass index; hence, she underwent a 5-cm right anterior thoracotomy to establish access to the pericardium. The sinoatrial (SA) node was ablated surgically by direct application under vision of the right atrium around the area of the SA node to avoid the phrenic nerve. Modification and ablation of the sinus node in patients exhibiting features of IST may be considered to help alleviate patients' symptoms. Further follow-up and assessments with large cohorts and powered randomized controlled studies are needed. Our case represents an example where a hybrid invasive approach resulted in a safe procedure with immediate symptomatic benefit.