Catch 22: a case of incessant ventricular tachycardia post-left ventricular assist device resulting in right ventricular failure, left ventricular cavity obliteration and failure of endocardial ventricular tachycardia ablation

Catheter Ablation of Ventricular Tachycardia in Patients With a Ventricular Assist Device: A Systematic Review of Procedural Characteristics and Outcomes

OBJECTIVES

This is a systematic review summarizing the procedural characteristics and outcomes of ventricular assist device (VAD)-related ventricular tachycardia (VT) ablation.

BACKGROUND

Drug-refractory VT refractory commonly develops post-VAD implantation. Procedural and outcome data come from small series or case reports.

METHODS

An electronic search was performed using major databases. Primary outcomes were VT recurrence, mortality, and cardiac transplantation. Secondary endpoints were acute procedural success and procedural complications.

RESULTS

Eighteen studies were included, with a total of 110 patients (mean age 59.6 ± 11 years, 89% men; VT storm 34%). Scar-related re-entry was the predominant mechanism of VT (90.3%) and cannula-related VT in 19.3% cases. Electroanatomical mapping interference occurred in 1.8% of cases; there were no reports of catheter entrapment. Noninducibility of clinical VT was achieved in 77.9%; procedural complications occurred in 9.4%. At a mean follow-up of 263.5 ± 267.0 days, VT recurred in 43.6%, 23.4% underwent cardiac transplant, and 48.1% died. There were no procedural-related deaths and no death was directly related to ventricular arrhythmia. In follow-up, there was a significant reduction in implantable cardioverter-defibrillator therapies or shocks (57.1% vs. 23.8%). Ablation allowed VT storm termination in 90% of patients.

CONCLUSIONS

VAD-related VT is predominantly related to pre-existing intrinsic myocardial scar rather than inflow cannula site insertion. Catheter ablation is a reasonable treatment strategy, albeit with expectedly high rate of recurrence, transplantation, and mortality related to severe underlying disease.

Electromagnetic Interference Between Left Ventricular Assist Device and a Three-Dimensional Mapping System Overcome by "Hot Mapping"

The number of patients with implanted left ventricular assist devices is constantly increasing. Numerous patients suffer from drug-resistant ventricular tachycardias. Only a few studies and reports about ablation therapy in this cohort of patients are available. Electromagnetic interferences between the left ventricular assist device and the three-dimensional mapping system which is used for ablation has been described as disabling the investigator to create a proper map of the left ventricle. We observed that this interference is interrupted by "hot mapping" meaning that one pretends an ablation with only 5 W, permitting the creation of a clear map in areas of interference.