title: Left ventricular mechanical assist devices and cardiac device interactions: an observational case series.
abstract: BACKGROUND
  Nonpulsatile left ventricular assist devices (LVADs) are increasingly used for treatment of refractory heart failure. A majority of such patients have implanted cardiac devices, namely implantable cardioverter-defibrillators (ICDs) or cardiac resynchronization therapy-pacemaker (CRT-P) or cardiac resynchronization therapy-defibrillator (CRT-D) devices. However, potential interactions between LVADs and cardiac devices in this category of patients remain unknown.
  
  
  METHODS
  We reviewed case records and device logs of 15 patients with ICDs or CRT-P or CRT-D devices who subsequently had implantation of a VentrAssist LVAD (Ventracor Ltd., Chatswood, Australia) as destination therapy or bridge to heart transplantation. Pacemaker and ICD lead parameters before and after LVAD implant were compared. In addition, ventricular tachyarrhythmia event logs and potential electromagnetic interference reports were evaluated.
  
  
  RESULTS
  Right ventricular (RV) sensing decreased in the first 6 months post-LVAD. Mean R-wave amplitude preimplant was 10.9 +/- 5.25 mV compared with 7.2 +/- 3.4 mV during follow-up (P = 0.02). RV impedance also decreased from 642 +/- 240 ohms at baseline to 580 +/- 212 ohms at follow-up (P = 0.007). There was a significant increase in RV stimulation threshold following implantation of the LVAD from 0.8 +/- 0.6 V at baseline to 1.4 +/- 1.0 V in the first 6 months postimplant (P = 0.01). A marked increase in ventricular tachyarrhythmia burden was observed in three patients. One patient displayed electromagnetic interference between the LVAD and defibrillator, resulting in inappropriate defibrillation therapy.
  
  
  CONCLUSIONS
  LVADs have a definite impact on cardiac devices in respect with alteration of lead parameters, ventricular tachyarrhythmias, and electromagnetic interference.
authors: Heart Institute, Tan Tock Seng Hospital, Singapore.
authors: David
authors: D
authors: Foo
authors: Bruce D
authors: BD
authors: Walker
authors: Dennis L
authors: DL
authors: Kuchar
authors: Charles W
authors: CW
authors: Thorburn
authors: Andre
authors: A
authors: Tay
authors: Christopher S
authors: CS
authors: Hayward
authors: Peter
authors: P
authors: Macdonald
authors: Anne
authors: A
authors: Keogh
authors: Eugene
authors: E
authors: Kotlyar
authors: Philip
authors: P
authors: Spratt
authors: Paul
authors: P
authors: Jansz
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D017147:Defibrillators, Implantable / Q000009:adverse effects*; D004868:Equipment Failure; D019544:Equipment Failure Analysis; D005260:Female; D006353:Heart-Assist Devices / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial / Q000009:adverse effects*; D012189:Retrospective Studies; D016896:Treatment Outcome; D014693:Ventricular Fibrillation / Q000175:diagnosis* / Q000209:etiology*; D055815:Young Adult