Answers

Short answers

1 Pericardial effusion or tamponade; obstruction of the superior vena cava

2 Echocardiograpy

3 Primary lung malignancy

Long answer
Outcome
Urgent echocardiography showed a large pericardial effusion causing haemodynamic compromise, shown by diastolic collapse of the right ventricle in diastole and greater variation in speed of blood flow across the mitral valve with respiration. On pericardiocentesis, 1 litre of blood stained fluid was aspirated and a percutaneous catheter drain inserted; symptoms improved somewhat but the jugular venous pressure remained high.

Analysis of the pericardial fluid showed an exudative effusion. No malignant cells were seen.

Computed tomography showed extensive bilateral lymphadenopathy extending retrosternally into the superior mediastinum, causing superior vena cava obstruction, with right basal lung field opacity consistent with primary lung carcinoma. The patient was unsuitable for stenting and radiotherapy because his clinical state was deteriorating rapidly. He died 12 hours after admission.

Clinical review
The presentation and management of pericardial effusion depends on the cause, clinical findings, and time course of presentation. Many patients with chronic idiopathic effusions may not have symptoms, as the pericardium has had time to expand; however, the complications of an acute effusion can be fatal, as cardiac output is rapidly compromised. This review discusses the recognition, investigation, and treatment of pericardial effusions.

Aetiology and epidemiology
Comprehensive epidemiological studies of pericardial effusion are few and far between, but in general autopsy studies, 3.4% of subjects have a pericardial effusion.¹

The aetiology varies geographically. The common causes of pericardial perfusion are infection (16-27%), malignancy (13-23%), and iatrogenic (13-18%) (commonly cardiac surgery or interventions, but also drug induced pericarditis, such as by clozapine²).^{3 4 5} The malignancies most often implicated are lung, lymphoma, and breast.⁶ In the United Kingdom, infective effusions are usually viral; bacterial infections (staphylococcal, tuberculous, etc) may also be responsible for pericardial effusion. Uraemia and autoimmune diseases are less common but important causes.³

Clinical evaluation
Establishing the patient’s medical background is essential, as any underlying, relevant disease is likely to be the cause of an effusion.⁷

Patients may have chest pain that is relieved by sitting up and exacerbated by lying flat. Dyspnoea and dysphagia are important symptoms caused by local compression. Phrenic nerve compression may cause hiccups, and recurrent laryngeal nerve compression may cause hoarseness.

Pericardial effusion without tamponade has few signs on examination—the jugular venous pressure can be raised, with a deep x descent (caused by rapid diastolic early filling), and Kussmaul’s sign (paradoxical rise of pressure on inspiration) may also be evident. Ewart’s sign has been described as dull percussion, increased vocal resonance, or bronchial breathing at the base of the left scapula. This is secondary to atelactasis caused by the enlarged pericardial sac.¹

Cardiac tamponade is a medical emergency and the patient may subsequently have cardiogenic shock. It is critical to examine for stigmata of haemodynamic compromise, and tamponade presents classically with Beck’s triad (quiet heart sounds on auscultation accompanied by hypotension and increased central venous pressure⁷). Measuring the patient’s blood pressure may show pulsus paradoxus (systolic blood pressure falling by more than 10 mm Hg on inspiration); this accurately estimates the degree of compromise in patients with tamponade.⁸

Differential diagnoses for patients with raised jugular venous pressure, hypotension, and dyspnoea should include pulmonary embolus and, rarely, myocardial wall rupture following infarction.

Clinicians should have a high index of suspicion for pericardial effusion when any of the above symptoms and signs are present on a background of pericarditis, myocardial infarction, malignancy, infection, recent thoracic procedures (particularly valve replacement), and autoimmune disease. A thorough drug history is also essential.

Investigations
Echocardiography establishes the diagnosis, provides clues about cause and prognosis, and guides percutaneous pericardial drainage.^{7 9 10 11} Pericardial effusions appear in the pericardial space as "echo-free" areas (see fig 1). The size of this area in diastole can be used to grade effusions.⁹

View larger version (55K): [in this window] [in a new window] [PowerPoint Slide for Teaching]   Fig 1 Dark "echo free" area (marked by the red lines) indicates a large pericardial effusion within which the heart sits

 
Echocardiography can confirm tamponade. Criteria include right sided collapse in diastole with two dimensional echocardiography; Doppler can show reciprocal variation in ventricular volumes and valvular inflow velocities with respiration.⁹ The diagnosis of tamponade needs to be made in the context of the clinical findings.

Investigations of pericardial effusion    Serology Inflammatory markers Renal disease (urea and electrolytes) Endocrine (hypothyroidism) Immunological (rheumatoid factor and antinuclear antibodies) Cardiac (raised troponin levels may match those seen in myocardial infarction12)    Pericardial fluid analysis Cytology Culture Biochemistry (pericardial fluid protein levels, glucose, lactate dehydrogenase, and cell count have debatable use in diagnosis13)    Electrocardiography Low voltage QRS complexes14 15 Electrical alternans (P and QRS)—almost always indicate effusion or tamponade16    Imaging Chest radiograph (enlarged cardiac silhouette—"water bottle heart" (fig 2); radiolucency with cardiopericardial shadow—"halo sign"17) Echocardiogram (grade effusion based on size; confirm or rule out tamponade) Transoesophageal echocardiogram (loculated effusions11) Computed tomography (pulmonary pathology) Magnetic resonance imaging (myocardial pathology)

View larger version (43K): [in this window] [in a new window] [PowerPoint Slide for Teaching]   Fig 2 Chest radiograph showing pericardial effusion

 
Management
Medical management involves treating symptoms and preventing recurrence of effusion. NSAIDs (non-steroidal anti-inflammatory drugs), especially ibuprofen, provide relief from chest pain;⁹ supplementation with colchicine reduces recurrence.^{18 19} Failure to respond to NSAIDs and colchicine is an indication for intravenous corticosteroids, as are uraemic pericarditis, and effusions secondary to connective tissue disorder.⁹ Where colchicine has already been used, however, steroids may actually increase the likelihood of recurrence.¹⁸

Effusions secondary to viral causes do not normally require specific pharmacological treatment.¹¹ Bacterial effusions, on the other hand, require empirical intravenous antibiotic therapy with an anti-staphylococcus antibiotic such as vancomycin, and an aminoglycoside.¹¹ This should be changed as necessary according to results of cultures.

A reducing course of prednisolone over two months in conjunction with antituberculous agents has been shown to reduce mortality in patients with tuberculous effusions.²⁰

Uraemic pericarditis requires renal replacement therapy, usually with haemodialysis.

The European Society of Cardiology states that cardiac tamponade is an absolute indication for therapeutic pericardiocentesis, a principle largely agreed worldwide.^{21 22} The life saving principles of the management of tamponade are immediate drainage and fluid resuscitation. The aim of the latter is to increase right sided filling pressures by giving intravenous fluids, but this should not delay pericardiocentesis. The patient should be monitored on a coronary care unit.

In pericardiocentesis, guidance with echocardiogram^{23 24} or fluoroscopy is preferable to blind performance. Fluoroscopy allows for haemodynamic monitoring via right heart catheterisation¹¹ and is particularly effective for very small effusions (<200 ml).²¹ Relative contraindications are bleeding diatheses and use of anticoagulants. Major complications secondary to pericardiocentesis include myocardial tissue and coronary vessel laceration, pneumothorax, and perforation of abdominal viscus.²¹

The rate of recurrence of malignant effusion is as high as 60%,^{25 26} so long term follow-up is necessary. This includes appropriate medical or surgical management of the underlying neoplasm.

Success rates for intrapericardial sclerosing agents, especially tetracycline, are high,⁷ but the adverse effects (fever, chest pain, and atrial arrhythmias) are common.⁹ Although the intrapericardial use of the chemotherapy agent cisplatin is useful in effusions secondary to lung cancer,²⁷ there is little evidence to support the use of other agents in reducing the recurrence rate of effusions in other malignancies. Intrapericardial radionuclides have yielded positive results, but the logistics of handling radioactive material have prevented widespread adoption of this technique.¹¹

When medical treatment and repeat pericardiocentesis have failed, the pericardium will require decompression. One such technique is percutaneous pericardiotomy—balloon inflation of the pericardium allows passage of fluid into the pleural space, where it is reabsorbed (but there is a risk of disseminating neoplastic cells).⁷ Surgical drainage of effusions is as effective as balloon pericardiotomy²⁸ and is recommended by the European Society of Cardiology in purulent effusions.⁹ Pericardioectomy, with its high mortality (4.2-5.6%^{29 30}), should be considered as a last resort, mainly as treatment for constrictive pericarditis.⁹

Cite this as: BMJ 2008;337:a2678