Characterization of ventricular tachycardia ablation in end-stage heart failure patients with left ventricular assist device (CHANNELED-Registry)

J.-H. van den Bruck (Köln)¹, M. Khalaph (Bad Oeynhausen)², D. Guckel (Bad Oeynhausen)², P. Sommer (Bad Oeynhausen)², K. Albert (Hannover)³, D. Duncker (Hannover)³, H. L. Estner (München)⁴, T. Deneke (Nürnberg)⁵, F. Hohendanner (Berlin)⁶, T. Gaspar (Dresden)⁷, S. Richter (Dresden)⁸, K. Seuthe (Köln)⁹, J. Wörmann (Köln)¹, A. Sultan (Hamburg)¹⁰, J.-H. Schipper (Köln)¹, L. Eckardt (Münster)¹¹, F. Doldi (Münster)¹¹, A. Metzner (Hamburg)¹², F. Moser (Kiel)¹³, H. Servatius (Bern)¹⁴, G. Thalmann (Bern)¹⁴, T. Reichlin (Bern)¹⁴, D. Steven (Köln)¹, J. Lüker (Köln)^1
1Herzzentrum der Universität zu Köln Elektrophysiologie Köln, Deutschland; ²Herz- und Diabeteszentrum NRW Klinik für Elektrophysiologie/ Rhythmologie Bad Oeynhausen, Deutschland; ³Medizinische Hochschule Hannover Klinik für Kardiologie und Angiologie Hannover, Deutschland; ⁴LMU Klinikum der Universität München Med. Klinik u. Poliklinik, Interventionelle Elektrophysiologie München, Deutschland; ⁵Klinikum Nürnberg Süd Kardiologie Nürnberg, Deutschland; ⁶Deutsches Herzzentrum der Charite (DHZC) Klinik für Kardiologie, Angiologie und Intensivmedizin | CBF Berlin, Deutschland; ⁷Städtisches Klinikum Dresden II. Medizinische Klinik Dresden, Deutschland; ⁸Herzzentrum Dresden GmbH an der TU Dresden Klinik für Innere Medizin und Kardiologie Dresden, Deutschland; ⁹Herzzentrum der Universität zu Köln Klinik III für Innere Medizin Köln, Deutschland; ¹⁰Asklepios Klinik St. Georg Kardiologie & internistische Intensivmedizin Hamburg, Deutschland; ¹¹Universitätsklinikum Münster Klinik für Kardiologie II - Rhythmologie Münster, Deutschland; ¹²Universitäres Herz- und Gefäßzentrum Hamburg Klinik für Kardiologie mit Schwerpunkt Elektrophysiologie Hamburg, Deutschland; ¹³Universitätsklinikum Schleswig-Holstein Innere Medizin III mit den Schwerpunkten Kardiologie, Angiologie und internistische Intensivmedizin Kiel, Deutschland; ¹⁴Inselspital - Universitätsspital Bern Klinik und Poliklinik für Kardiologie Bern, Schweiz

Background

Left-ventricular-assist-devices (LVAD) are an established therapy for patients with end-stage heart failure. These patients are at high risk for ventricular tachycardia (VT) and ICD-shocks due to the arrhythmogenic substrate of the underlying cardiomyopathy itself and as the LVAD cannula might be arrhythmogenic, too.

 

Objective

Data on catheter ablation of VT in LVAD patients are scarce and current evidence predominantly consists of case reports and small single-center series. This multi-center registry seeks to systematically assess the mechanism and origin of VA in LVAD patients and to evaluate procedural parameters and outcome of VT ablation in this special subset of patients (NCT06063811).

 

Methods

Retrospective data of LVAD patients referred for VT ablation at 10 tertiary care centers between January 2017 and August 2023 were included in this multicenter registry. VT mechanisms, procedural data, clinical follow-up, and outcome were assessed.

 

Results

We report 42 patients (88% male, age 61±8 years) undergoing 44 ablation procedures included in this ongoing registry. The underlying cardiomyopathy was ischemic in 20/42 patients (48%) and nonischemic in 22/42 patients (52%) with a mean left ventricular ejection fraction of 21%±6% before LVAD implantation. Most catheter ablations were conducted after prior antiarrhythmic drug (AAD) treatment (14/44 on amiodarone, 9/44 after prior intensification of amiodarone treatment, 17/44 after prior combination of two or more AADs). A total of 70 VTs were targeted (32/44 transseptal, 3/44 retrograde aortic, 9/44 combined approaches) and 11/42 patients required VT ablation less than 1 month after LVAD implantation. Of the targeted VTs the majority (69%) were cardiomyopathy related and only 31% of the targeted VTs were presumably related to the LVAD cannula. In 5/44 procedures access site complications and in 1/44 procedures a pericardial effusion occurred; one patient showed a post procedural oxygen desaturation; despite immediate intubation the patient deceased from hypoxic brain injury. No LVAD related complications were observed. A follow-up was available for 33/42 patients. During a median follow-up of 277 days (IQR 78-625 days), 5/33 patients were transplanted and 13/33 died. Patients died after a median time of 124 days (IQR 34-952 days) primarily from heart failure, sepsis, or intracranial bleeding. Of the remaining 15/33 patients, 6/15 patients were arrhythmia-free at a median follow-up of 212 days (IQR 78-639 days).

 

Conclusion

Although often chosen as last resort, catheter ablation of VT in LVAD patients is feasible and can be performed safely in this critically ill subset of heart failure patients in experienced centers. Intrinsic myocardial scar seems to be the dominant substrate in these patients but LVAD cannulae contribute to a significant number of VTs. In the presence of severely reduced LV function the VT recurrence remains high despite maximal therapy and prognosis of these patients is limited.