Successful subcutaneous implanted cardioverter-defibrillator therapy using alternate vector in a patient post-implantation of heartware left ventricular assist device
Lahiri MK, Singh G, Khan A, Schuger CD. Successful subcutaneous implanted cardioverter-defibrillator therapy using alternate vector in a patient post-implantation of heartware left ventricular assist device. Heart Rhythm. 2017;14(5):S226-S227.
Background: The HeartWare Left Ventricular AssistDevice (LVAD) often causes electromagnetic interference in Subcutaneous Implantable Cardioverter Defibrillators (S-ICD), causing inappropriate delivery or suppression of therapy. Successful therapy for ventricular tachycardia (VT) by an S-ICD in a patient with coexisting HeartWare LVAD has never been reported. Objective: Our objective is to present a case of successful diagnosis and treatment of VT in a patient with a HeartWare LVAD using the alternate (sternal) vector of the S-ICD. Methods: N/A Results: A 42 year old man with nonischemic heart failure (HF), ejection fraction 22%, underwent S-ICD implantation for primary prevention of sudden death. His clinical HF worsened, and he subsequently underwent successful HeartWare LVAD implant. Due to electromagnetic noise, the S-ICD settings were adjusted to include only the alternate vector (distal-to-proximal sternal electrode) for detection. Later at home he had spontaneous VT, which was appropriately detected and converted with a single 80 Joule shock. His clinical course post-shock was uneventful with normal LVAD function. Conclusion: S-ICDs are capable of appropriate detection and treatment of VT in patients with HeartWare LVADs. While concern over electromagnetic interference is well-founded and appropriate alterations must be made to device detection (namely, use of the alternate detection vector only), this case demonstrates that in select situations, patients may still derive protection from the S-ICD after HeartWareLVAD implant. (Figure presented).