Pulmonary Hypertension: Causes and Risk Factors

Introduction

Pulmonary hypertension (PH) is a condition characterized by high blood pressure in the arteries that supply the lungs. This increased pressure can strain the heart, leading to complications such as heart failure. Understanding the causes of PH is crucial for proper diagnosis and treatment.

Main Causes of Pulmonary Hypertension

There are several underlying causes, classified into five groups according to the World Health Organization (WHO):

1. Pulmonary Arterial Hypertension (PAH)

• Idiopathic (no known cause)
• Genetic mutations (e.g., BMPR2 gene mutation)
• Drug-induced (e.g., appetite suppressants, methamphetamine use)
• Associated with diseases like connective tissue diseases (scleroderma, lupus), HIV infection, portal hypertension, or congenital heart disease

2. PH Due to Left Heart Disease

• Heart failure with preserved or reduced ejection fraction
• Valvular diseases (mitral valve stenosis, aortic stenosis)
• Left ventricular dysfunction

3. PH Due to Lung Diseases and/or Hypoxia

• Chronic obstructive pulmonary disease (COPD)
• Interstitial lung disease
• Sleep apnea
• High-altitude exposure

4. Chronic Thromboembolic Pulmonary Hypertension (CTEPH)

• Caused by chronic blood clots blocking pulmonary arteries
• Often results from an untreated or recurrent pulmonary embolism

5. PH Due to Multifactorial Mechanisms

• Blood disorders (sickle cell anemia)
• Metabolic disorders (thyroid disease, glycogen storage disease)
• Chronic kidney disease

Risk Factors for Pulmonary Hypertension

• Family history of PH
• Autoimmune disorders (scleroderma, lupus)
• Chronic lung diseases (COPD, pulmonary fibrosis)
• Obesity and obstructive sleep apnea
• Drug and toxin exposure (certain chemotherapy drugs, illicit drug use)
• Blood clots in the lungs (pulmonary embolism)

Importance of Early Diagnosis

Since pulmonary hypertension can be progressive and life-threatening, early diagnosis and treatment are critical. Symptoms such as shortness of breath, fatigue, chest pain, and dizziness should prompt further medical evaluation. Diagnostic tests may include echocardiography, right heart catheterization, pulmonary function tests, and imaging studies.

Conclusion

Pulmonary hypertension is a complex condition with multiple causes, requiring a thorough understanding for appropriate treatment. If you or your loved ones have risk factors or symptoms, seek medical advice promptly.

Source recommendations

1. 2022 European Society of Cardiology Guidelines on Pulmonary Hypertension

1. https://www.escardio.org/Guidelines/Clinical-Practice-Guidelines/Pulmonary-Hypertension-Guidelines-on-Diagnosis-and-Treatment-of
2. https://academic.oup.com/eurheartj/article/43/38/3618/6673929
3. https://pubmed.ncbi.nlm.nih.gov/36017548/
4. https://publications.ersnet.org/content/erj/early/2022/08/25/1399300300879-2022.abstract
5. https://www.acc.org/Latest-in-Cardiology/ten-points-to-remember/2022/08/30/19/11/2022-ESC-Guidelines-for-Pulmonary-Hypertension-ESC-2022

2. 2022 American Heart Association / American College of Cardiology Pulmonary Hypertension Guidelines

1. https://www.ahajournals.org/doi/10.1161/CIR.0000000000001063
2. https://www.acc.org/Guidelines
3. https://www.ahajournals.org/doi/10.1161/CIR.0000000000001106
4. https://www.jacc.org/doi/10.1016/j.jacc.2023.03.393
5. https://www.acc.org/Latest-in-Cardiology/ten-points-to-remember/2022/11/01/12/21/2022-guideline-on-aortic-disease-2-gl-ad