Constrictive Pericarditis

How constriction affects the heart

The pericardium is a two-layered sac that normally holds a small amount of lubricating fluid and lets the heart move freely. After inflammation, the layers can thicken and fuse, forming a stiff shell, often only a few millimeters thick, sometimes with calcium deposits.

The heart can begin to fill normally, but filling stops abruptly when it hits the rigid shell. Because all four chambers are trapped together, pressures rise and become equal throughout the heart, and blood backs up into:

• the veins of the body, causing swelling, liver congestion and fluid in the abdomen
• to a lesser extent, the lungs, causing breathlessness

A characteristic feature is that the left and right ventricles compete for space: when one fills more with breathing, the other fills less (ventricular interdependence).

Causes

Only a small fraction of people with acute pericarditis develop constriction, with the risk higher after bacterial and tuberculous pericarditis.

Symptoms

Symptoms develop slowly over months to years:

• swelling of the legs and ankles
• abdominal swelling from fluid (ascites) and an enlarged liver
• fatigue and reduced exercise tolerance
• shortness of breath, particularly with exertion
• weight loss and muscle wasting in advanced cases
• loss of appetite and abdominal discomfort

A doctor may find raised neck veins that rise further when breathing in (Kussmaul sign), a "pericardial knock" sound and a large liver.

Diagnosis

Constriction is often missed and mistaken for liver disease or heart failure.

• Echocardiogram: shows septal bounce, respiratory variation in filling, and a dilated inferior vena cava
• CT scan: measures pericardial thickness and calcification
• Cardiac MRI: shows thickening and inflammation; inflamed pericardium suggests a chance of improvement with medicines
• Cardiac catheterization: measures pressures in both sides of the heart; equal pressures and characteristic waveforms confirm constriction
• Blood tests: BNP, liver and kidney function, inflammatory markers
• Tests for tuberculosis where relevant

Constrictive pericarditis vs restrictive cardiomyopathy

Both cause similar symptoms. In restrictive cardiomyopathy, the heart muscle itself is stiff and the pericardium is normal. Distinguishing them matters because constriction can be cured by surgery and restrictive cardiomyopathy cannot.

Treatment

Medical treatment

• Anti-inflammatory therapy: NSAIDs, colchicine and sometimes steroids for recent or "transient" constriction with active inflammation on MRI or blood tests. About 10 to 20% of cases resolve within a few months.
• Diuretics to reduce swelling and fluid buildup; they relieve symptoms but do not fix the problem.
• Treatment of tuberculosis with anti-TB medicines, which reduces progression to constriction in tuberculous pericarditis.

Pericardiectomy

For chronic constriction, surgical removal of as much of the pericardium as possible is the definitive treatment. It is a major operation with higher risk than many heart surgeries, especially in people with previous radiation or advanced disease, so it should be performed at experienced centers. Outcomes are best when done before severe symptoms develop.

Outlook

After successful pericardiectomy, many people have marked symptom improvement. Long-term outcomes are best for idiopathic cases and poorer after radiation-induced constriction, which often involves damage to the heart muscle and valves as well.

Frequently asked questions

What causes constrictive pericarditis?

It develops when inflammation causes the sac around the heart to scar and stiffen. Common causes are previous viral or idiopathic pericarditis, heart surgery and chest radiation. Tuberculosis is a leading cause in many parts of the world.

What are the symptoms of constrictive pericarditis?

Symptoms usually develop slowly and include swelling of the legs and abdomen, tiredness, breathlessness on exertion and raised neck veins. Because these resemble heart failure or liver disease, the condition is often diagnosed late.

Is constrictive pericarditis curable?

Often, yes. Early or transient cases can resolve with anti-inflammatory medicines. Chronic constriction is treated by pericardiectomy, surgery to remove the stiff pericardium, which relieves symptoms in many people.

How long can you live with constrictive pericarditis?

It depends on the cause, how advanced it is and whether surgery is done. Untreated chronic constriction tends to worsen over time. People who have pericardiectomy before severe disease develops often do well for many years.