P1817Impact of left ventricular assist devices on the occurrence of malignant ventricular tachyarrhythmias in heart failure patients with implantable defibrillators

Background: The exact role of implantable defibrillator (ICD) in primary prevention of sudden death in patients (pts) with left ventricular assist devices (LVAD) remains to be precised. Very limited information is available on the impact of LVAD on occurrence of malignant ventricular tachyarrhythmias (VTA) - ventricular tachycardia / fibrillation (VT/VF) Purpose: In this retrospective study we aimed to analyse the occurrence and type of VTAs together with the type of ICD interventions prior and post LVAD implantation in a single tertiary care centre. Patients and methods: We have analysed a cohort of 33 pts with end-stage systolic heart failure with implanted ICDs and LVADs. LVADs were implanted in the years 2008-2015: all were continuous flow devices. The aetiology of heart failure was dilated cardiomyopathy in 17 pts , coronary heart disease in 9 pts and congenital heart disease in 1 pt. Six pts (18%) died within 30 days after LVAD implantation. From the 27 surviving pts with LVAD 17 pts were implanted with ICD, 8 pts with CRT-D, 1 pt had CRT-P and 1 pt dual-chamber PM. Twenty three were men, mean age of the cohort was 47.7±10.7 years. At the time of LVAD implant mean INTERMACS score was 2.56 ± 1.15, mean LVEF 18.8 ± 4.7%, mean CI 1.82 ± 0.37 l/min/m2. Mean follow-up duration was 30±35 months before LVAD implantation and 15±10 months after LVAD implantation. At the end of follow-up 11 pts underwent heart transplantation (41%), 8 pts died (30%), 6 pts were listed for heart transplantation (22%) and LVAD was destination therapy in 2 pts (7%) Results: Seventeen pts (63%) were free of VT/VF. Prior to LVAD implantation 9 pts (33.3%) had overall 40 VT episodes and 9 VF episodes. Following LVAD implantation 5 pts had 64 VT episodes and 11 VF episodes. Total annual per patient incidence of VTA increased post LVAD implantations from 0.59 to 1.92 and from 0.13 to 0.33 (episodes/pt/year) for VT and VF, respectively. In 6 pts with pre-LVAD occurrence of VT/VF the arrhythmia burden was reduced after LVAD, in 3 pts the burden increased. New VT/VF episodes after LVAD implant emerged only in 1 pt. Inappropriate ICD interventions were observed in 5/25 pts (20%) and accounted for 1/3 of all anti-tachycardia interventions. Annual incidence of inappropriate ICD interventions post-LVAD was 0.8 episodes/pt/year. Conclusions: 1. In the analysed patient cohort we have observed a decreased number of pts with VT/VF post LVAD implantation. However, the total burden of VT/VF episodes increased. 2. VTA post LVAD implant occurred mainly in those pts who had VTA episodes already prior to LVAD. 3. Up to 1/3 of ICD interventions post LVAD were inappropriate. 4. Patients without VTA prior to LVAD implantation manifested a relatively low risk of VTA post-LVAD. Based on our observations in pts without ICD prior to LVAD implantation we recommend ICD implantation post-LVAD only for secondary prevention of VTA.