Definition

Cor pulmonale is a condition where the right side of the heart fails due to structural and functional changes, typically caused by a primary lung disease.

Causes

Long-term high blood pressure in the pulmonary arteries, known as pulmonary hypertension, is the underlying mechanism of cor pulmonale. In pulmonary hypertension, changes occur in the small blood vessels of the lungs, leading to increased pressure when the right side of the heart pumps blood to the lungs. This forces the heart to work harder. Over time, this persistent high pressure causes structural changes in the right heart, such as thickening or dilation of the heart walls, as a way to compensate for the increased workload. Eventually, the heart becomes overworked and can no longer compensate, resulting in cor pulmonale.

Several lung conditions can lower blood oxygen levels and increase pulmonary pressure over time, leading to cor pulmonale. These conditions include:

• Chronic obstructive pulmonary disease (COPD), which is the most common cause of cor pulmonale. The severity of cor pulmonale correlates with the severity of COPD
• Autoimmune diseases that damage the lungs, such as scleroderma
• Chronic blood clots in the pulmonary arteries
• Cystic fibrosis
• Severe bronchiectasis
• Interstitial lung disease that scars lung tissue
• Severe spinal deformities (kyphoscoliosis), which restrict lung expansion
• Obstructive sleep apnea (OSA), where breathing stops during sleep
• Respiratory issues caused by obesity
• Thickening and narrowing of pulmonary blood vessels from unknown causes
• Other causes: sarcoidosis, polycythemia vera (which thickens the blood and triggers pulmonary hypertension), vasculitis, lung tumors, etc

Cor pulmonale can occur suddenly, often due to conditions that rapidly increase pulmonary pressure, such as:

• Severe pulmonary embolism (blockage in the pulmonary arteries).
• Acute respiratory distress syndrome (abnormal development of the respiratory system).
• Use of mechanical ventilation (breathing assistance machines).

Right heart failure due to left heart failure, congenital heart disease, or other non-pulmonary causes is not considered cor pulmonale.

Risk Factor

Several risk factors can lead to cor pulmonale, including:

• Smoking
• Air pollution
• Blood thickening
• Obesity
• Advanced age

Symptoms

Shortness of breath or lightheadedness during activity is often an early symptom of cor pulmonale. You may also feel a fast heartbeat or experience heart palpitations. Over time, symptoms may occur even during light activity or rest.

Common symptoms of cor pulmonale include:

• Fatigue
• Fainting during physical activity, especially in severe cases where the heart cannot meet the increased oxygen demand
• Chest discomfort, usually in the front of the chest
• Chest pain, especially during exertion
• Swelling or enlargement of the abdomen
• Swelling in the legs or ankles
• Symptoms of lung disease, such as wheezing, coughing, or mucus production
• Bluish tint to the lips and fingers
• Coughing up blood
• In rare cases, pulmonary artery dilation can compress the vocal cord nerves, causing hoarseness
• In advanced stages, liver enlargement may occur, leading to a loss of appetite, upper right abdominal pain, and yellowing of the skin and eyes

These symptoms often appear long after the onset of pulmonary hypertension, indicating that the disease is advanced and severe.

Diagnosis

To diagnose cor pulmonale, your doctor will ask about your medical history and symptoms. A physical exam may reveal:

• Fluid accumulation in the abdomen
• Abnormal heart sounds
• Bluish skin
• Enlarged liver
• Swelling in the neck veins, indicating right heart failure
• Leg swelling

Several tests may be performed to confirm the diagnosis, identify the cause, and assess complications. These tests include:

• Chest X-ray: This can show enlargement of the right heart and pulmonary arteries
• Echocardiography: Provides detailed information about heart condition
• EKG: Shows possible thickening of the right heart wall, right heart fatigue, and any lung disease
• Blood tests
• BNP (brain natriuretic peptide) levels: BNP is a hormone released when there is an increase in blood volume and stress on heart cells
• CT scan and ventilation-perfusion scan (V/Q scan) to check for pulmonary embolism
• Lung biopsy (rarely performed)
• Blood oxygen levels through a blood gas test
• Lung function tests to assess lung disease severity
• MRI (rarely performed)
• Tests for autoimmune lung diseases
• Right heart catheterization: this is the most accurate test for diagnosing and assessing the severity of pulmonary hypertension

Management

The main goal of treating cor pulmonale is to control symptoms by improving oxygenation and right heart function. It's also crucial to treat the underlying medical issues causing pulmonary hypertension, as they may lead to cor pulmonale.

Several treatment options are available, typically chosen based on the cause. Treatments include:

• Blood thinners to prevent clots in the pulmonary arteries
• Medications to manage heart failure symptoms, such as drugs that remove excess salt and fluids
• Oxygen therapy
• Lung or heart-lung transplantation if medications are ineffective

Medicines for cor pulmonale come in various forms: oral, intravenous, or inhaled. Do not stop taking prescribed medications without your doctor's guidance.

If you have cor pulmonale, steps to stabilize your condition include:

• Avoiding heavy physical activity and lifting
• Avoiding high altitudes
• Getting flu and pneumonia vaccines
• Quitting smoking
• Limiting salt and fluid intake as directed by your doctor
• Using oxygen as prescribed
• Consult your doctor before planning a pregnancy

Complications

Cor pulmonale can lead to complications such as:

• Severe shortness of breath, which can be life-threatening
• Significant fluid buildup in the body
• Shock
• Death

Prevention

You can prevent cor pulmonale by maintaining heart and lung health. This can be achieved by:

• Keep a healthy weight
• Regular exercise
• Eating a balanced, healthy diet
• Avoid smoking, as it can cause lung disease leading to cor pulmonale

When to See a Doctor?

Consult a doctor if you experience shortness of breath or chest pain.