title: A low resting heart rate at diagnosis predicts favourable long-term outcome in pulmonary arterial and chronic thromboembolic pulmonary hypertension. A prospective observational study.
abstract: BACKGROUND
  A low resting heart rate (HR) is prognostically favourable in healthy individuals and in patients with left heart disease. In this study we investigated the impact of HR at diagnosis on long-term outcome in patients with differently classified precapillary pulmonary hypertension (pPH).
  
  
  METHODS
  pPH patients diagnosed as pulmonary arterial (PAH) or inoperable chronic thromboembolic pulmonary hypertension (CTEPH) were registered and regularly followed at our centre Baseline characteristics and events defined as either death or lung transplantation were noted. The prognostic value of HR was analysed using Kaplan Meier estimates, live tables and Cox regression.
  
  
  RESULTS
  206 patients with PAH (148) and inoperable CTEPH (58) were included. The median HR was 82 bpm. pPH with a HR below 82 bpm had a significantly longer overall event-free survival (2409 vs.1332 days, p = .000). This advantage was similarly found if PAH and CTEPH were analysed separately. Although a lower HR was associated with a better hemodynamic and functional class, HR was a strong and independent prognostic marker for transplant free survival even if corrected for age, sex, hemodynamics and functional status.
  
  
  CONCLUSIONS
  We show that resting HR at diagnosis is a strong and independent long-term prognostic marker in PAH and CTEPH. Whether reducing HR by pharmacological agents would improve outcome in pPH has to be assessed by future trials with high attention to safety.
authors.affiliation: Department of Heart, Vessel, Thorax, University Hospital of Zurich, Zurich, 8091, Switzerland.
authors.forename: Florian F
authors.initials: FF
authors.lastname: Hildenbrand
authors.forename: Ivan
authors.initials: I
authors.lastname: Fauchère
authors.forename: Lars C
authors.initials: LC
authors.lastname: Huber
authors.forename: Stephan
authors.initials: S
authors.lastname: Keusch
authors.forename: Rudolf
authors.initials: R
authors.lastname: Speich
authors.forename: Silvia
authors.initials: S
authors.lastname: Ulrich
mesh_terms: D015897:Comorbidity; D004562:Electrocardiography / Q000379:methods / Q000706:statistics & numerical data*; D005260:Female; D006339:Heart Rate; D006801:Humans; D006976:Hypertension, Pulmonary / Q000175:diagnosis* / Q000453:epidemiology* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011379:Prognosis; D011446:Prospective Studies; D011655:Pulmonary Embolism / Q000175:diagnosis* / Q000453:epidemiology* / Q000503:physiopathology; D012042:Registries; D015203:Reproducibility of Results; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D013557:Switzerland / Q000453:epidemiology