Chapter 1 - Cardiac Complications of Cancer and Anti-Cancer Treatment
Aetiology
Malignant cardiac involvement is not an infrequent event, its incidence at autopsy being around 10% in patients with known malignancies.
Neoplastic diseases that most frequently present involvement of the pericardium are advanced lung cancer (approximately 30% of patients with lung cancer present pericardial involvement), breast cancer (approximately 25% of patients), malignant melanoma (40%–70% of patients) and leukaemia and lymphomas (around 15% of patients). In addition, chemotherapy-related effusions are occasionally observed (up to 1%–2% incidence) following exposure to busulfan, cytarabine, cyclophosphamide or tretinoin, especially when these drugs are used at high doses or in combination for the treatment of haematological malignancies.
Evaluation
As fluid accumulates in the pericardium, the increase in intrapericardial pressure affects diastolic filling of the heart, leading to decreased cardiac output. Symptoms may arise gradually or rapidly, depending on fluid accumulation rate, and may range from dyspnoea, chest pain, cough, palpitations and orthopnoea, to fatigue, anxiety and confusion. At physical examination, tachycardia, decreased heart sounds, neck vein distension, peripheral oedema and pericardial friction rubs may be present. Pulsus paradoxus, defined as an inspiratory decrease of more than 10 mmHg in systolic pressure, is a rare but suggestive sign of pericardial effusion. As cardiac tamponade develops, patients may show signs of low-output shock.
At initial evaluation, a chest radiograph may provide evidence of an enlarged cardiac silhouette, while at electrocardiography (ECG) low-voltage complexes and electrical alternans are suggestive of pericardial effusion. However, two-dimensional echocardiography is considered the standard method for diagnosing pericardial effusion.
Pericardiocentesis is usually needed to establish aetiology, the malignant nature of pericardial effusion being confirmed by identification of malignant cells at cytological examination.
Treatment
Treatment depends on the underlying aetiology and symptom progression. In patients with minimal symptoms without haemodynamic implications, systemic management is warranted, especially in chemosensitive cancers, and radiotherapy may also be indicated.
In patients with mild hypotension, rapid volume expansion by infusion of normal saline or Ringer’s lactate may increase the right ventricular filling pressure above the pericardial pressure, improving cardiac output. However, immediate pericardiocentesis is mandatory and life-saving for patients with tamponade. If no systemic therapy can control the pericardial effusion, local measures, such as subxiphoid pericardiostomy, with or without intrapericardial instillation of sclerosing or cytotoxic agents, percutaneous balloon pericardiotomy and pericardial window, may be considered.
