Introduction
The introduction of left ventricular assist devices (LVADs) into
clinical practice over the past decade has improved the care of patients
with end-stage heart failure.1-3 Many patients have an
existing implantable cardioverter defibrillator (ICD) at the time of
LVAD implantation. LVAD Implantation can alter ICD lead parameters
including RV capture threshold, RV lead impedance and R wave sensing
.4,5,6 Reduced R wave sensing can result in under
sensing of malignant ventricular arrythmias (VAs), and hence withhold
appropriate therapy including anti-tachycardia pacing and shocks. On the
other hand, oversensing of noise generated by the LVAD, can result in
inappropriate ICD shocks. Furthermore, the impact of LVAD implantation
on defibrillation thresholds has not been clearly established. To our
knowledge, no study has systematically looked at DFTs both pre and post
LVAD implantation.
Recently, there have been reports of LVAD patients presenting with
multiple ineffective ICD shocks.7 Whether shock
failure is the result of LVAD implantation or the patient’s severe
cardiomyopathy is unknown. The workup of post LVAD patients with
preexisting ICDs presenting with ineffective ICD shocks is limited.
Especially the importance of an exhaustive history and physical
examination in such patients is considered to be low yield. We present a
case of failed ICD shocks in an LVAD patient due to the presence of a
metal tongue ring. Our case highlights the importance of a dedicated
history and thorough physical examination.