Chronic Pericarditis

Chronic pericarditis is long-lasting, gradual inflammation of the pericardium causing accumulation of fluid in the pericardial space or thickening of the pericardium. Hence there are two main types encompassed by this term: chronic effusive pericarditis and chronic constrictive pericarditis. The chronic varieties of pericarditis are rare.

Acute pericarditis will usually have preceded chronic pericarditis (although acute pericarditis is more common and usually self-limiting).
Effusive-constrictive pericarditis¹ (persistence of symptoms and signs of constrictive pericarditis after removal of pericardial fluid) suggests a clinical continuum initiated by acute pericarditis and progressing through pericardial effusion, chronic effusive pericarditis, effusive-constrictive pericarditis to chronic constrictive pericarditis.
Unsurprisingly there are shared aetiological factors with treatment according to the cause and which particular clinical syndrome is diagnosed.

The normal pericardium has 2 layers (outer fibrous pericardium and inner serous pericardium) and there is about 50mls of fluid in the intrapericardial space or pericardial cavity (the space between the serous pericardium next to the heart and the serous pericardium next to the fibrous pericardium) The pericardium:

• Helps cardiac efficiency (limits dilatation, aids atrial filling etc).
• Protects the heart (reduces external friction and is a barrier to extension of infection and malignancy).
• Fixes the heart anatomically through ligamentous connections.

Many different diseases can affect the pericardium and cause the different clinical syndromes associated with chronic pericarditis. The range of aetiologies should be considered alongside prevalence as many on the list are possible but unlikely diagnoses.

• Idiopathic:
  • It is common for no antecedent diagnosis to explain the inflammatory process.
  • Unrecognised viral pericarditis (coxsackievirus, echovirus and adenovirus) may explain some of these, which constitutes the most common aetiological factor for all froms of pericarditis (both acute and chronic) particularly in developed countries.
• Infection:
  • Infection can be viral, bacterial, fungal or parasitic.
  • Tuberculosis is the main cause of constrictive pericarditis in developing nations but is less common in developed countries.
• Inflammation:
  • Many different inflammatory conditions can affect the pericardium.
  • Between 11 and 50% of patients with rheumatoid arthritis have pericarditis at autopsy.
  • SLE, scleroderma, sarcoidosis, Wegener's granulomatosis, and others can all cause chronic pericarditis.
• Metabolic:
  • Renal failure (35-50% of patients with uraemia, pre-dialysis have pericarditis).
  • Hypothyroidism.
  • Cholesterol pericarditis (Gold paint pericarditis).
• Cardiovascular disease:
  • Myocardial infarction causes acute pericarditis (transmural infarcts, persistent ST elevation).
  • Dresslers (2-3 weeks after myocardial infarction).
  • Aortic dissection.
• Neoplastic:
  • 5-17% of pericarditis.
  • This is caused mostly by metastatic disease (lung 33%, breast 25%, haematological 15%).
• Miscellaneous:
  • Drugs:doxorubicin; cyclophosphamide; drug induced SLE (methyldopa, isoniazid, hydralazine); methysergide; smallpox vaccination; dantrolene, phenytoin; minoxidil.
  • Irradiation
  • Post pericardiotomy syndrome (i.e. after cardiac surgery 10-40%).
  • Trauma especially with oesophageal rupture or pancreatitis.

• Causes: most commonly idiopathic but can follow any of the causes of acute pericarditis particularly malignancy (most commonly breast and lung), tuberculosis (more common in developing countries) or hypothyroidism.
• Symptoms:
  • Variable but dyspnoea on exertion particularly in severe cases.
  • Cardiovascular symptoms include: chest pain, pressure or discomfort; syncope, light headedness; palpitations.
  • Many patients are asymptomatic until the disease is advanced (up to 2L of fluid can build up).
  • Respiratory symptoms including cough and hoarseness may occur.
  • Other symptoms include fatigue, hiccoughs anxiety and confusion.
  • Attention should be given to any history of specific antecedent conditions (e.g. cardiac surgery, renal failure, radiation treatment, malignancy, tuberculosis).
• Signs may include hypotension, elevated JVP, and diminished heart sounds (Beck triad or acute compression triad described in 1935 with cardiac tamponade). Signs may develop towards those of cardiac tamponade (Beck triad, pulsus paradoxus, Kussmaul sign etc). Cardiac dullness is an unreliable sign. Pericardial friction rub best heard in the supine position at the end of exhalation. Hepatojugular reflux may be observed.
• Fluid and hence signs usually develop slowly with cardiac tamponade developing late as a complication.

• Causes: again these parallel those of antecedent acute pericarditis and hence are many and varied. However
  • The more common causes of constrictive pericarditis are:
    • Idiopathic
    • Viral
    • Tuberculosis (the highest total incidence as common in developing countries)
    • Mediastinal irradiation (5-10 years later)
    • Post surgical (including cardiac catheterisation)
  • Less common causes are:
    • Other infections
    • Neoplasms
    • Uraemia
    • Connective tissue disorders
    • Drugs
    • Trauma
    • Cardiovascular disease
  • Other aetiologies are rare (hereditary, chemical trauma etc)
• Symptoms and signs are:
  • In the early stages subtle and easily missed
  • In advanced disease the patient may be ill with jaundice, cachexia and muscle wasting
  • Similar to right heart failure, commonly dyspnoea (which may be relatively slight), peripheral oedema, JVP elevated (classically with a prominent y descent (Friedreich's sign), and doesn't fall with inspiration (Kussmaul's sign)
  • Additionally there may be pulsatile hepatomegaly (in as many as 70% of patients), reduced apical impulse, a pericardial "knock" (early diastolic sound) and pulsus paradoxus.²
  • A patient with intense venous congestion, but no heart enlargement or valvular disease, should lead one to suspect constrictive pericarditis
  • GI symptoms are secondary to this venous congestion.
• Typically very gradual onset (usually months, occasionally days). The pericardium becomes thickened and fibrotic (and later "egg-shell" calcification visible on CXR in ~27%).³
  Heart is not enlarged. ECG - may be low voltage with non-specific T-wave changes.

• Chronic constrictive pericarditis.
  The main differential diagnosis is:
  • Restrictive cardiomyopathy⁴ others include:
  • Dilated cardiomyopathy
  • Pericardial effusion
  • Cardiac neoplasms.
• Chronic effusive pericarditis.
  The differential diagnoses include:
  • Cardiac tamponade
  • Dilated cardiomyopathy
  • Constrictive pericarditis
  • Constrictive-effusive pericarditis
  • Pulmonary oedema

• Echocardiogram (tissue doppler imaging and colour M-mode echocardiography) is usually diagnostic and helps distinguish from restrictive cardiomyopathy (in the former myocardial relaxation is normal and diastolic dysfunction is due impaired compliance and limited cardiac diastolic volume).
• Magnetic resonance imaging (MRI) can estimate thickness of the pericardium. Late enhancement techniques may be particularly effective.⁵
• Cardiac catheterisation is sometimes used to measure pressures.
• Occasionally pericardial biopsy, especially if infective, malignant or granulomatous causes are suspected.
• New experimental devices to access the pericardial space, even in the absence of effusion, are being developed and these may improve future diagnostic and therapeutic options.⁴

• Treat cause where possible.
• Chronic effusive pericarditis:
  Usually conservative approach if not haemodynamically compromised or not too symptomatic. Otherwise surgical drainage may be required (particularly if infection is suspected).⁶
• Constrictive pericarditis:
  • Medical: bed rest, diuretics, salt restriction can relieve symptoms.
  • Surgical: Pericardiectomy is curative in most cases (85%), but mortality from the procedure is significant (5-15%). The best results are achieved if surgery is offered early. The surgical results are poor in patients with organ failure (e.g. renal and hepatic particularly), ascites, untreated coronary artery disease, old age, NYHA class IV, postradiation pericarditis and myocardial fibrosis.⁶

• Richard Lower, notable for the first human blood transfusion in England in 1667 (the first ever, occurred in Paris earlier in the same year), described a patient with dyspnoea and intermittent pulse in 1669.
• Lancisi, notable for suggesting the connection between malaria and mosquitoes, recommending swamp drainage to prevent it, reported on the constrictive syndrome in 1828.
• Corrigan is credited with the pericardial knock in 1842.
• Kussmaul published his paper on the paradoxical pulse in 1873.²
• Franz Volhard collaborated with Viktor Schmieden in 1923, leading to the first pericardiectomy for constrictive pericarditis.