title: Myocardial perfusion SPECT identifies patients with left bundle branch block patterns at high risk for future coronary events.
abstract: BACKGROUND
  The value of myocardial perfusion SPECT (MPS) for patients with left bundle branch block (LBBB) or right ventricular apical (RVA) pacing seems reduced. The prognosis of patients with only abnormal activation related perfusion defects (AARD) due to LBBB or RVA-pacing is similar to those with a normal MPS. We assessed the prognostic value of MPS in patients with LBBB or RVA pacing.
  
  
  METHODS
  Patients with LBBB or RVA pacing referred for vasodilator stress MPS between April 2002 and January 2006 were analyzed. Group 1 are patients with normal MPS and MPS with AARD. Group 2 are patients with an MPS with a perfusion defect extending outside the AARD area. Events were cardiac death, acute myocardial infarction and coronary revascularization.
  
  
  RESULTS
  In Group 1 (101 patients) 12 events and in Group 2 (96 patients) 45 events occurred during a mean follow-up of 2.6 +/- 1.5 years. The prognosis of Group 2 was significantly worse (49%) compared with Group 1 (91%). The annual cardiac death rate was 0.7%/year in Group 1 and 6.4%/year in Group 2 (P < .001). The prognosis of patients with LBBB was not different from those with RVA pacing.
  
  
  CONCLUSIONS
  Group 2 had a significantly worse cardiac prognosis compared to Group 1. The annual cardiac death rate of <1% in Group 1 warrants a watchful waiting strategy, whereas the cardiac death rate in Group 2 warrants aggressive invasive coronary strategies.
authors.affiliation: Department of Nuclear Medicine, Sint Antonius Hospital, Nieuwegein, Koekoekslaan 1, 3435 CM, Nieuwegein, The Netherlands. timtencate@yahoo.com
authors.forename: Tim J F
authors.initials: TJ
authors.lastname: ten Cate
authors.forename: Johannes C
authors.initials: JC
authors.lastname: Kelder
authors.forename: Herbert W M
authors.initials: HW
authors.lastname: Plokker
authors.forename: J Fred
authors.initials: JF
authors.lastname: Verzijlbergen
authors.forename: Norbert M
authors.initials: NM
authors.lastname: van Hemel
mesh_terms: D000368:Aged; D002037:Bundle-Branch Block / Q000175:diagnosis* / Q000000981:diagnostic imaging*; D003324:Coronary Artery Disease / Q000175:diagnosis* / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology; D010477:Perfusion; D011379:Prognosis; D012189:Retrospective Studies; D013997:Time Factors; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D016896:Treatment Outcome; D014665:Vasodilator Agents
chemical_list: D014665:Vasodilator Agents