title: Venous obstruction after pacemaker implantation.
abstract: BACKGROUND
  Central vein leads are known to predispose to venous obstruction. Although usually asymptomatic, obstruction may render electrode removal difficult. This study aimed at quantifying changes in venous calibers in a prospective fashion by intravenous contrast venography (ICV) before and after pacemaker (PM) or cardioverter-defibrillator implantation.
  
  
  METHODS
  One hundred and fifty (mean age 67; 61% male) consecutive patients were enrolled, and followed for 6 months. A successful ICV was done at baseline prior to implantation and at 6-month follow-up in 136 (91%) patients. Minimum (D(min)) and maximum (D(max)) vessel diameters were obtained from both ICVs. A new stenosis was defined as a 50% diameter reduction in a venous segment when compared to baseline. We implanted a total of 230 electrodes: 47 (34.6%) single lead, 84 (61.8%) 2-lead, and 5 (3.7%) 3-lead systems.
  
  
  RESULTS
  At baseline ICV, 10 patients (7%) were found to have venous anomalies, including 8 patients with obstructive lesions, 1 patient with a persistent left superior vena cava, and 1 patient with double axillary vein. At 6 months, a new obstructive venous lesion had developed in a total of 19 (14%) patients, none of whom exhibited any local symptoms. Of these patients 14 (10%) had a stenosis (mean D(min) 4.6 mm and diameter 38% of baseline), and 5 (3.6%) had a complete venous occlusion. In most cases the new stenosis developed in a location where the vessel was narrowest at baseline. Clinical predictors for the development of stenosis were atrial fibrillation at baseline and biventricular PM implantation.
  
  
  CONCLUSIONS
  This is the first systematic study to quantify venous changes after PM or ICD implantation. Our study shows that venous anomalies rendering PM implantation difficult are not infrequent. The incidence of new venous obstruction was 14%. Atrial fibrillation and biventricular PM implantation were independent predictors of venous obstruction.
authors.affiliation: Turku University Hospital, Turku, Finland. Petri.korkeila@tyks.fi
authors.forename: Petri
authors.initials: P
authors.lastname: Korkeila
authors.forename: Kai
authors.initials: K
authors.lastname: Nyman
authors.forename: Antti
authors.initials: A
authors.lastname: Ylitalo
authors.forename: Juhani
authors.initials: J
authors.lastname: Koistinen
authors.forename: Pasi
authors.initials: P
authors.lastname: Karjalainen
authors.forename: Juha
authors.initials: J
authors.lastname: Lund
authors.forename: K E Juhani
authors.initials: KE
authors.lastname: Airaksinen
mesh_terms: D000368:Aged; D002304:Cardiac Pacing, Artificial / Q000009:adverse effects*; D004567:Electrodes, Implanted / Q000009:adverse effects*; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D008297:Male; D010138:Pacemaker, Artificial / Q000009:adverse effects*; D016896:Treatment Outcome; D014463:Ultrasonography; D020246:Venous Thrombosis / Q000000981:diagnostic imaging* / Q000209:etiology*