Room air insufflation through the right atrial appendage to facilitate epicardial access in ventricular tachycardia ablation: a safe and reproducible approach

Abstract Background and Aim Pericardial access is often the limiting step in epicardial ventricular tachycardia (VT) ablation. This report describes a reproducible method in which filtered room air is insufflated through the right atrial appendage (RAA) to transiently outline pericardial reflections, enabling safer subxiphoid entry without the need for CO2. Methods Ten patients undergoing epicardial VT ablation were included. Under general anesthesia, RV (quadripolar) and CS (decapolar) catheters were placed, and a JR-4 catheter inside an AGILIS sheath was advanced into the RAA. RAA angiography was performed in RAO 30°. The distal anterior RAA was punctured using a HORNET 0.014-inch guidewire inserted into a 1.5×15 mm OTW balloon. With gentle forward pressure, the wire punctured the RAA, and the wire–balloon assembly was advanced into the pericardial space. After wire removal, the balloon was connected to a 50-cc syringe, and 50 cc of filtered room air was insufflated until 2–3 cm of pericardial separation was seen in lateral view. Subxiphoid epicardial access was then obtained with a 17-gauge Tuohy needle. The OTW balloon was withdrawn, an AGILIS sheath was inserted into the pericardial sac, and the air was aspirated. Results Epicardial access was achieved in all cases. No air-related adverse events were observed, and the pericardial air dissipated within minutes. Procedural and fluoroscopy times were comparable to CO2-based techniques. All patients underwent successful epicardial ablation without complications or delayed pericardial effusion. One patient had an incidental small RAA thrombus detected by transthoracic echocardiography; it was successfully treated with slow-infusion alteplase (1 mg/h for 48 h) followed by short-term apixaban, with no clinical sequelae. Discussion This low-cost method may enhance the feasibility of epicardial VT ablation in centers without CO2 delivery systems. Filtered room air provided sufficient visualization of pericardial reflections without hemodynamic or embolic complications. Safety depends on controlled micro-bolus delivery, sterile filtration, continuous imaging, and readiness for immediate aspiration. Further studies are needed to compare room air with CO2 and define optimal volume limits. Conclusion Filtered room-air insufflation through the RAA is a safe, effective adjunct for facilitating epicardial access when performed with strict monitoring. It offers a practical and reproducible alternative to CO2-based methods, particularly in resource-limited settings.Figure 1Figure 2