title: Incidence and prognosis of pacemaker lead-associated masses: a study of 1,569 transesophageal echocardiograms.
abstract: Endovascular lead infection is an uncommon but serious problem. Transesophageal echocardiography (TEE) is a useful tool for identification of pacemaker lead vegetations. Additionally, incidental echogenic masses are occasionally identified by TEE. The prognosis and optimal treatment of either suspected lead infection or an incidental mass is poorly understood.
  
  
  OBJECTIVE
  The purpose of this study was to examine the incidence and clinical course of pacemaker lead masses.
  
  
  METHODS
  A total of 1,569 sequential TEE examinations performed from January 2002 to January 2005 were reviewed. Retrospective chart analysis of patients with a pacing lead-associated mass was performed to review the indication for TEE as well as clinical management. Telephone follow up was also performed.
  
  
  RESULTS
  During 125 TEE examinations, pacemaker leads were visualized in the right-sided chambers. Fifteen studies demonstrated an echogenic mass associated with the lead. In 9 of these studies, endocarditis was suspected, and the mass was felt to be a vegetation: 6 were treated with antibiotics alone, with 1 death attributed to a complication of endocarditis (autopsy proven massive pulmonary embolus); 3 patients were treated with lead extraction, both were alive at follow up; 1 patient was lost to follow up after the TEE. Six patients (5%) were found incidentally to have a mass on the pacing lead during TEE: 3 were treated with warfarin; 2 received no specific therapy; and 1 underwent surgical debridement of the lead during valve surgery. All of the patients in this group were alive at follow up, and no significant clinical events attributable to the lead-associated mass were observed.
  
  
  CONCLUSIONS
  TEE identified an echogenic mass on 12% of the leads imaged, with 60% having suspected endocarditis. The mortality rate of lead vegetation was 11%. An incidental mass was noted on 5% of the leads, with no significant associated morbidity or mortality observed.
authors.affiliation: Winthrop-University Hospital, 215 Grant Avenue, Mineola, NY 11501, USA. lo@mad.scientist.com
authors.forename: Ronald
authors.initials: R
authors.lastname: Lo
authors.forename: Michael
authors.initials: M
authors.lastname: D'Anca
authors.forename: Todd
authors.initials: T
authors.lastname: Cohen
authors.forename: Todd
authors.initials: T
authors.lastname: Kerwin
mesh_terms: D001145:Arrhythmias, Cardiac / Q000401:mortality* / Q000628:therapy; D017548:Echocardiography, Transesophageal; D004567:Electrodes, Implanted / Q000009:adverse effects / Q000382:microbiology / Q000706:statistics & numerical data; D004697:Endocarditis, Bacterial / Q000000981:diagnostic imaging* / Q000209:etiology / Q000401:mortality*; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D010138:Pacemaker, Artificial / Q000009:adverse effects / Q000382:microbiology / Q000706:statistics & numerical data*; D011379:Prognosis; D016459:Prosthesis-Related Infections / Q000000981:diagnostic imaging / Q000401:mortality; D012189:Retrospective Studies; D015996:Survival Rate