Impact of hemodynamic support in high-risk VT ablation procedures

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Introduction It is an ongoing debate whether VT ablation is better performed in SR or during VT. During SR patients are in stable conditions, however, VT mechanisms can only be visualized during VT. Hemodynamic stability during VT is critical and is shorter in patients with structural heart disease and severely reduced left ventricular ejection fraction (LVEF). In unstable VT with need for cardioversion, the risk of map anatomy shifts is increased, but a precise anatomical reconstruction is crucial for successful ablation. Considering hemodynamic support during VT ablation, handling must be easy and as little disruptive to the ablation procedure as possible. Percutaneous left ventricular support systems with appropriate access size seem to be the most suitable, but are limited in their support capacity. The aim of this study was to evaluate, whether a hemodynamic support of a maximum of 3,5 L/min is sufficient to ensure hemodynamic stability even in faster VT. Methods The study enrolled patients with a history of one or more sustaining VTs and severely reduced LVEF. Procedure was performed under deep sedation. Transseptal and transaortal access was prepared to access the LV. In epicardial cases an additional subxiphoidal access was used. Impella CP with SmartAssist was introduced via the opposite groin. Hemodynamic support was started immediately after placement. VTs were induced via programmed RV and burst pacing. VT was mapped and ablated with the Carto 3 Mapping system. The need to frequently adjust pump setting, duration of hemodynamic stability during VT, identification of VT mechanism and ablation success were evaluated. Results 8 patients with a total of 21 VTs have been mapped, analyzed and ablated. 4/8 patients received epi-/endocardial ablation. With hemodynamic support, all VTs could be mapped under stable conditions (CLmedian VT = 360ms). 87,5% could be terminated during catheter ablation, in 50% no VT was reinducible after ablation. The median time for Impella placement was 20min. The Smart Assist Mode enabled an easy handling without the necessity of manual adjustments during the course of the case. The Impella could be explanted at the end of the procedure in 7 out of 8 cases. Femoral closure was done with either Proglide or AngioSeal closure device. Post procedural, one patient developed a segmental stenosis of the A. femoralis superficialis, most likely due to the Proglide device. This case was treated conservatively and recovered after a few months. Conclusion Hemodynamic support of a maximum of 3,5L/min provides adequate and effective support for mapping of sustained VTs. No manual adjustment was required and patients could in general be weaned directly at the end of the procedure. Broader benefits of this concept need to be evaluated in further studies.