title: Initial single-center experience of a quadripolar pacing lead for cardiac resynchronization therapy.
abstract: BACKGROUND
  The Quartet model 1458Q (St. Jude Medical, Sylmar, CA, USA) lead is a quadripolar left ventricular (LV) lead with pace/sense capability from four electrodes (tip and three rings). The lead is capable of pacing in 10 different configurations rather than the three that are available in conventional bipolar pacing leads. We describe a single-center initial experience of the use of this lead in patients undergoing cardiac resynchronization therapy (CRT).
  
  
  METHODS
  Twenty-eight patients for a CRT with cardiac defibrillator were implanted between October 2009 and May 2010 with a Quartet lead . Lead position, pacing parameters, stability, complications, and presence of phrenic nerve stimulation (PNS) data were collected at implant and predischarge. Follow-up data were collected at 15 ± 8 weeks for all patients.
  
  
  RESULTS
  A Quartet lead was successfully implanted in 96% (27/28) of patients (age 61 ± 15 years; 82% male; ischemic etiology 50%; mean left ventricular [LV] ejection fraction 25 ± 7%; left bundle branch block 68%). PNS was seen at implant in 11 patients (41%) with at least one vector. In eight of these cases (72%), the need for lead repositioning was averted by programming LV pacing utilizing the additional vectors available with the Quartet lead.
  
  
  CONCLUSIONS
  These initial data suggest that pacing with the Quartet lead is associated with a high implant success rate and stable pacing parameters acutely and at short-term follow-up. The 10 LV pacing vectors available with this lead may allow PNS and capture threshold problems to be easily overcome.
authors.affiliation: Guys and St. Thomas' Hospital NHS Foundation Trust King's College London, London, UK. anoop.shetty@kcl.ac.uk
authors.forename: Anoop K
authors.initials: AK
authors.lastname: Shetty
authors.forename: Simon G
authors.initials: SG
authors.lastname: Duckett
authors.forename: Julian
authors.initials: J
authors.lastname: Bostock
authors.forename: Debashis
authors.initials: D
authors.lastname: Roy
authors.forename: Matthew
authors.initials: M
authors.lastname: Ginks
authors.forename: Shoaib
authors.initials: S
authors.lastname: Hamid
authors.forename: Eric
authors.initials: E
authors.lastname: Rosenthal
authors.forename: Reza
authors.initials: R
authors.lastname: Razavi
authors.forename: Christopher Aldo
authors.initials: CA
authors.lastname: Rinaldi
mesh_terms: D058409:Cardiac Resynchronization Therapy Devices; D004567:Electrodes, Implanted; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005260:Female; D006333:Heart Failure; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D016896:Treatment Outcome