title: Long-term stability of endocardial left ventricular pacing leads placed via the coronary sinus.
abstract: BACKGROUND
  Left ventricular endocardial pacing leads placed via the coronary sinus (CS) are increasingly implanted to achieve cardiac resynchronization therapy (CRT); however, the long-term stability of these leads is unknown. We sought to determine the implant success and long-term stability of CS leads in our single center experience.
  
  
  METHODS
  All consecutive patients who underwent CRT via implantation of the CS lead between January 1999 and December 2005 were included. Pacing thresholds at implant and during long-term follow-up were reviewed and the rate of acute (within 24 hours of implant) and chronic (>24 hours) lead failure was determined.
  
  
  RESULTS
  A total of 512 patients (mean age 68 +/- 12 years; 409 [80%] male) underwent CRT device implantation and were included. The CS lead implantation was successful on the initial implantation in 487 patients (95%) and subsequently successful in six patients (24%) in whom initial attempts were unsuccessful. Acute lead failure occurred in 25 patients (5.1%) and was most commonly due to persistent extra-cardiac stimulation. The rate of chronic lead failure was 4% in the first year and remained stable during long-term follow-up. The CS lead pacing thresholds remained stable with only minimal increase (1.42 +/- 0.85 V/0.42 +/- 0.25 ms vs 1.51 +/- 1.05 V/0.47 +/- 0.29 ms; P = 0.04).
  
  
  CONCLUSIONS
  Placement of a left ventricular pacing lead via the CS is feasible and safe in the vast majority of patients. Once placed, the CS leads remain stable with excellent pacing thresholds over the longer term.
authors.affiliation: Division of Cardiovascular Diseases, Department of Medicine, Mayo Clinic, Rochester, Minnesota 55905, USA.
authors.forename: Grace
authors.initials: G
authors.lastname: Lin
authors.forename: Nandan S
authors.initials: NS
authors.lastname: Anavekar
authors.forename: Tracy L
authors.initials: TL
authors.lastname: Webster
authors.forename: Robert F
authors.initials: RF
authors.lastname: Rea
authors.forename: David L
authors.initials: DL
authors.lastname: Hayes
authors.forename: Peter A
authors.initials: PA
authors.lastname: Brady
mesh_terms: D002304:Cardiac Pacing, Artificial / Q000401:mortality* / Q000706:statistics & numerical data; D054326:Coronary Sinus / Q000601:surgery*; D004567:Electrodes, Implanted / Q000706:statistics & numerical data*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D008910:Minnesota / Q000453:epidemiology; D019919:Prosthesis Implantation / Q000379:methods / Q000401:mortality; D012042:Registries; D018570:Risk Assessment; D012307:Risk Factors; D016019:Survival Analysis; D015996:Survival Rate; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000401:mortality* / Q000517:prevention & control*