title: Syncope paradox in the outcome of patients with pulmonary thromboembolism: short-term and midterm outcome.
abstract: OBJECTIVE
  We compare the early and midterm outcomes of pulmonary thromboembolism (PTE) in patients with and without syncope in our single-center registry.
  
  
  METHODS
  Between December 2006 and May 2013, 351 consecutive patients (mean age = 60.21 ± 16.91 years, 55.3% male) with confirmed acute symptomatic PTE were divided in with and without syncope groups. Groups were compared in terms of the effect of syncope on 30-day mortality and adverse events, and mortality in a median follow-up time of 16.9 months.
  
  
  RESULTS
  From 351 patients, 39 (11.1%) had syncope and 312 (88.9%) did not. Syncope group had less frequently chest pain (30.8% vs 51.4%; P value = 0.015). Also, the rates of 30-day adverse events and mortality were 12.8% and 5.1% for the group with syncope, and 14.4% and 10.3% for the group without syncope, respectively, with no significant difference. At follow up, 65 patients died and mortality was 18.5% for 351 patients (5.1% in the group with syncope and 20.2% for the other group). After adjustment for confounding factors, the effect of syncope on 30-day adverse events and mortality remained non-significant and on the midterm mortality was significant, showing that the presence of syncope was associated with lower midterm mortality (P value = 0.038).
  
  
  CONCLUSIONS
  Among PTE patients in our registry, 11.1% presented with syncope. Relationship between syncope and 30-day adverse events and mortality remained non-significant after adjustments for other factors. However, in midterm follow up, patients with syncope were significantly at decreased risk of mortality compared to those without syncope.
authors.affiliation: Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Seyyed-reza
authors.initials: SR
authors.lastname: Seyyedi
authors.affiliation: Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Yaser
authors.initials: Y
authors.lastname: Jenab
authors.affiliation: Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Masoumeh Lotfi
authors.initials: ML
authors.lastname: Tokaldany
authors.affiliation: Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Shapoor
authors.initials: S
authors.lastname: Shirani
authors.affiliation: Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Saeed
authors.initials: S
authors.lastname: Sadeghian
authors.affiliation: Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Arash
authors.initials: A
authors.lastname: Jalali
mesh_terms: D000328:Adult; D000368:Aged; D042241:Early Diagnosis; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011655:Pulmonary Embolism / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy; D012042:Registries; D055502:Secondary Prevention; D013575:Syncope / Q000209:etiology / Q000503:physiopathology*
keywords: mortality; prognosis; pulmonary thromboembolism; syncope