Idiopathic pulmonary arterial hypertension

Last reviewed: 28 Aug 2023
Last updated: 05 May 2023



History and exam

Key diagnostic factors

  • age 20-50 years
  • female sex
  • dyspnea
  • accentuated pulmonic component (P2) to the second heart sound
  • tricuspid regurgitation murmur
  • family history
More key diagnostic factors

Other diagnostic factors

  • fatigue
  • peripheral edema
  • cyanosis
  • stimulant use
  • syncope
  • chest pain
  • near syncope
  • early diastolic, high-pitched murmur in the pulmonary area
  • jugular vein distension
Other diagnostic factors

Risk factors

  • family history
  • female sex
  • bone morphogenetic protein receptor type 2 (BMPR2) mutations
  • appetite suppressants
  • drugs and toxins
More risk factors

Diagnostic investigations

1st investigations to order

  • chest radiography
  • ECG
  • transthoracic Doppler echocardiography
  • right heart catheterization
  • antinuclear antibodies (ANA)
  • pulmonary function tests
  • arterial blood gas (ABG)
  • nocturnal oximetry
  • ventilation-perfusion (V/Q) scintigraphy
  • 6-minute walk test
  • B-type natriuretic peptide (BNP) or N-terminal proBNP (NT-proBNP)
  • CBC
  • LFTs
  • thyroid function tests
  • HIV serology
More 1st investigations to order

Investigations to consider

  • high-resolution chest CT scan ± CT pulmonary angiography
  • cardiac MRI
  • vasodilator testing with inhaled nitric oxide, inhaled iloprost, or intravenous epoprostenol
More investigations to consider

Treatment algorithm


positive response to acute vasoreactivity testing with no contraindication to calcium-channel blockers

negative response to acute vasoreactivity testing or contraindication to calcium-channel blockers: without cardiopulmonary comorbidity



Muhammad Sameed, MD

Pulmonary & Critical Care Fellow

Respiratory Institute

Cleveland Clinic




MS declares that he has no competing interests.

Gustavo A. Heresi, MD, MS
Gustavo A. Heresi

Director, Pulmonary Vascular and CTEPH Program

Department of Pulmonary and Critical Care Medicine

Respiratory Institute

Cleveland Clinic




GAH has received speaking and advisory board fees from Bayer Healthcare, the manufacturer of riociguat.


Dr Muhammad Sameed and Dr Gustavo A. Heresi would like to gratefully acknowledge Dr Raed A. Dweik, a previous contributor to this topic.


RAD declares that he has no competing interests.

Peer reviewers

Michael J. Krowka, MD

Division of Pulmonary and Critical Care Medicine

Mayo Clinic College of Medicine




MJK declares that he has no competing interests.

Charlie Elliot, MB ChB, MRCP

Consultant Physician in Respiratory and General Internal Medicine

Sheffield Pulmonary Vascular Disease Unit

Royal Hallamshire Hospital




CE has received reimbursement for attending several conferences as well as lecture fees from Actelion Pharmaceuticals, GSK, and Bayer.

Maria Giovanna Triveri, MD, PhD

​Assistant Professor of Cardiology,

Medical Director of the Pulmonary Hypertension Program

Icahn School of Medicine at Mount Sinai Hospital

New York



MGT has participated on Advisory Boards of Bayer and Actelion and received financial compensation for attendance.

  • Idiopathic pulmonary arterial hypertension images
  • Differentials

    • Pulmonary arterial hypertension (PAH) associated with left heart diseases (pulmonary venous hypertension)
    • PAH associated with lung respiratory diseases and/or hypoxia
    • PAH due to chronic thrombotic and/or embolic disease
    More Differentials
  • Guidelines

    • ACR appropriateness criteria® suspected pulmonary hypertension
    • 2022 ESC/ERS guidelines for the diagnosis and treatment of pulmonary hypertension
    More Guidelines
  • padlock-lockedLog in or subscribe to access all of BMJ Best Practice

Use of this content is subject to our disclaimer