Primary Pulmonary Hypertension (PPH)

Introduction

Primary pulmonary hypertension (PPH), now more commonly referred to as idiopathic pulmonary arterial hypertension (IPAH), is a rare but serious condition characterized by progressive elevation of blood pressure in the pulmonary arteries without an identifiable secondary cause.

Pathophysiology

In PPH, the pulmonary arteries become narrowed, thickened, and stiff, leading to increased resistance to blood flow. This forces the right side of the heart to work harder to pump blood into the lungs, eventually leading to right heart failure.

Causes

Although the exact cause remains unknown, PPH is associated with: - Genetic mutations (e.g., BMPR2 gene mutations in familial cases) - Endothelial dysfunction, leading to excessive vasoconstriction - Abnormal proliferation of vascular smooth muscle - Imbalance of vasodilators (e.g., nitric oxide, prostacyclin) and vasoconstrictors (e.g., endothelin-1)

Symptoms

PPH symptoms are often nonspecific and may include: - Shortness of breath (especially during exertion) - Fatigue - Dizziness or fainting (syncope) - Chest pain - Swelling in the legs and abdomen (signs of right heart failure) - Cyanosis (bluish discoloration of lips and skin due to low oxygen levels)

Diagnosis

PPH is a diagnosis of exclusion. Key diagnostic steps include: 1. Echocardiography – Estimates pulmonary artery pressure. 2. Right heart catheterization – Gold standard for definitive diagnosis, measuring pulmonary artery pressure directly. 3. Pulmonary function tests – To rule out other lung diseases. 4. CT or MRI of the chest – To assess pulmonary vasculature. 5. Genetic testing – In cases with a family history.

Treatment

While there is no cure, treatment aims to improve symptoms and slow disease progression:

1. Vasodilators

• Prostacyclin analogs (e.g., Epoprostenol, Treprostinil) – potent pulmonary vasodilators.
• Endothelin receptor antagonists (e.g., Bosentan, Ambrisentan).
• Phosphodiesterase-5 inhibitors (e.g., Sildenafil, Tadalafil) – improve blood flow.

2. Oxygen Therapy

• Supplemental oxygen helps maintain adequate oxygen levels and reduce shortness of breath.

3. Anticoagulation

• Some patients benefit from anticoagulants (e.g., Warfarin) to reduce the risk of clot formation.

4. Diuretics

• Reducing fluid overload can help alleviate symptoms of right heart failure.

5. Lung Transplantation

• Considered for severe cases when medical therapy is no longer effective.

Prognosis

• Without treatment, PPH has a poor prognosis, with a median survival of just a few years.
• With proper management, many patients achieve symptom relief and improved quality of life.

Conclusion

PPH is a serious and life-threatening condition that requires early diagnosis and aggressive management. If you experience symptoms like shortness of breath or fainting, consult a cardiologist or pulmonologist promptly.

Source recommendations

1. 2022 European Society of Cardiology/European Respiratory Society Guidelines for the Diagnosis and Treatment of Pulmonary Hypertension

1. https://pubmed.ncbi.nlm.nih.gov/36017548/
2. https://publications.ersnet.org/content/erj/early/2022/08/25/1399300300879-2022
3. https://academic.oup.com/eurheartj/article/43/38/3618/6673929
4. https://www.escardio.org/Guidelines/Clinical-Practice-Guidelines/Pulmonary-Hypertension-Guidelines-on-Diagnosis-and-Treatment-of
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 College of Cardiology/American Heart Association Guidelines for Pulmonary Hypertension

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/articles/2017/11/08/11/47/mon-5pm-bp-guideline-aha-2017