title: Predicting the Need for Upfront Combination Therapy in Pulmonary Arterial Hypertension.
abstract: BACKGROUND
  Combination therapy is commonly used for pulmonary arterial hypertension (PAH) treatment. We aimed to identify factors that may predict the need for future combination therapy.
  
  
  METHODS
  We conducted a retrospective chart review of consecutive patients with PAH in an aim to describe baseline clinical, echocardiogram, and hemodynamic characteristics of patients who eventually required combination therapy during the course of their disease and compared them to the ones who were maintained on monotherapy.
  
  
  RESULTS
  The monotherapy group was followed for an average of 31.8 ± 18.8 months and the combination therapy group was followed for an average of 28.7 ± 13.6 months. Among the 71 patients analyzed, a significantly higher number of patients who eventually required combination therapy belonged to World Health Organization functional class 3 (45% vs 37%) and 4 (23% vs 0) at baseline, compared with those on monotherapy (P < .05). Combination group also had a higher Registry to Evaluate Early And Long-term PAH Disease Management (REVEAL) PAH risk score at presentation. End of 6-minute walk test (6MWT), oxygen saturation (Spo 2) was also lower in the combination therapy group, 86% ± 8% versus 91% ± 7% (P < .05). Patients who eventually required combination therapy were more frequently noticed to have right ventricular enlargement, right atrial enlargement, and had a higher resting estimated right ventricular systolic pressure (RVSP). Right heart catheterization-derived hemodynamics data at baseline showed that the combination therapy group had a higher mean pulmonary artery (PA) pressure, lower pulmonary capillary wedge pressure, lower cardiac output, and higher pulmonary vascular resistance (PVR). On univariate analysis, only PVR ≥300 dyne·s/cm(5), mean PA pressure of ≥40 mm Hg, estimated RVSP ≥ 60 mm Hg, PAH risk score ≥ 10, and end of 6MWT saturation of ≤ 90% were of significance.
  
  
  CONCLUSIONS
  Patients with PAH who require combination therapy in the course of their disease have worse hemodynamics, PAH risk score, functional class, and end of 6MWT oxygen saturation at the time of presentation compared to patients maintained on monotherapy.
authors.affiliation: Division of Pulmonary, Critical Care and Sleep Medicine, University of Florida, Jacksonville, FL, USA abubakr.bajwa@jax.ufl.edu.
authors.forename: Abubakr A
authors.initials: AA
authors.lastname: Bajwa
authors.affiliation: Division of Pulmonary, Critical Care and Sleep Medicine, University of Southern California, la mirada, CA, USA.
authors.forename: Tauseef
authors.initials: T
authors.lastname: Qureshi
authors.affiliation: Division of Pulmonary, Critical Care and Sleep Medicine, University of Florida, Jacksonville, FL, USA.
authors.forename: Adil
authors.initials: A
authors.lastname: Shujaat
authors.affiliation: Division of Pulmonary, Critical Care and Sleep Medicine, University of Florida, Jacksonville, FL, USA.
authors.forename: Vandana
authors.initials: V
authors.lastname: Seeram
authors.affiliation: Division of Pulmonary, Critical Care and Sleep Medicine, University of Florida, Jacksonville, FL, USA.
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Jones
authors.affiliation: Division of Pulmonary, Critical Care and Sleep Medicine, University of Florida, Jacksonville, FL, USA.
authors.forename: Farah
authors.initials: F
authors.lastname: Al-Saffar
authors.affiliation: Division of Pulmonary, Critical Care and Sleep Medicine, University of Florida, Jacksonville, FL, USA.
authors.forename: James D
authors.initials: JD
authors.lastname: Cury
mesh_terms: D000959:Antihypertensive Agents / Q000008:administration & dosage* / Q000627:therapeutic use; D006328:Cardiac Catheterization / Q000379:methods; D002302:Cardiac Output / Q000502:physiology; D004359:Drug Therapy, Combination; D005080:Exercise Test; D005260:Female; D005500:Follow-Up Studies; D006439:Hemodynamics; D006801:Humans; D006976:Hypertension, Pulmonary / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood*; D012189:Retrospective Studies; D014655:Vascular Resistance / Q000502:physiology
chemical_list: D000959:Antihypertensive Agents; D010100:Oxygen
keywords: cardiovascular disease; combination therapy; predictors; pulmonary arterial hypertension