Introduction: We recently evaluated the feasibility and safety of the EpiAccess®System with a novel epicardial access needle in a multicenter study. The pressure monitoring capability identified successfully the epicardial space, facilitating access and minimizing complications.
Methods: We analyzed the EpiAccess System signals and calculated the average pericardial and right ventricular (RV) myocardial pressure. Successful epicardical access, defined as the ability to introduce a guidewire into the epicardial space, was assessed and confirmed with fluoroscopy. Significant pericardial bleeding was defined >80mL.
Results: Eighteen patients with a clinical need for epicardial access were enrolled. Patients were male (76%) with a mean age of 61.9 (range 28.4 to 84.1) years. Epicardial access for VT ablation was indicated in 76% of the patients. Successful epicardial access was obtained in all cases with pressure monitoring indicating pericardial wire access in all cases. No device related effusions occurred. The mean epicardial space pressure was 4.72±1.7mmHg (range 2.2-9.6). The mean RV myocardial pressure was 21.2± 4.4 (range 13.4-27.7). Epicardial access was obtained in average of 280 seconds. No RV perforations were reported. Elevated RV myocardial signal most likely represents close proximity of the needle to this structure. The pressure sensing is located in the tip of the needle and only needs to be 0.3mm into the myocardium to transmit high frequencies. Therefore, if the higher amplitude signal is observed we usually slightly withdraw the needle while observing the pressure signal until the pericardial signal appears at which time the guidewire can be inserted.
Conclusion: Epicardial access with the novel EpiAccess Needle and System with real time pressure monitoring is feasible and safe. The difference in pressures between epicardial space and RV myocardium is significant and might help guiding epicardial access.