Pericardial Tamponade – Top USMLE Diseases

Acute coronary syndrome (ACS) encompasses conditions that include confirmed or suspected myocardial ischemia or myocardial infarction (MI). ACS, which includes non-ST-elevation MI (NSTEMI), ST-elevation MI (STEMI), and unstable angina, usually results from thrombus formation on a ruptured atherosclerotic plaque in the epicardial arteries. Patients most commonly present with chest pain but also may have atypical symptoms. Diagnosis is by clinical history, ECG changes, elevated cardiac enzymes (preferably, high-sensitivity cardiac troponin), and/or evidence of wall motion abnormalities on imaging. Both STEMI and NSTEMI have loss of myocardial tissue, but STEMI is due to transmural ischemia (indicating complete major coronary artery obstruction). NSTEMI occurs because of subendocardial ischemia (indicating partial major coronary artery obstruction). Unstable angina occurs when ischemia does not result in infarction (no troponin elevation and typically with non-ST-elevation changes on ECG). Management of STEMI depends on the timing of the presentation and local resources with regard to thrombolytic therapy versus percutaneous intervention. Both unstable angina and NSTEMI are managed the same way, with both conservative (medical) and invasive strategies available. Additionally, routine medical therapy includes dual antiplatelet therapy, nitrates, oxygen, pain control, and beta-blockers.

Pericarditis is an inflammation of the pericardium, often with fluid accumulation.  It can be caused by infection (often viral), myocardial infarction, drugs, malignancies, metabolic disorders, autoimmune disorders, or trauma.  Acute, subacute, and chronic forms exist.  Acute pericarditis is usually idiopathic and manifests as fever, pleuritic chest pain, and an audible pericardial rub by auscultation. Diffuse upwardly concave ST-segment elevations in the initial ECG and pericardial effusion on echocardiography confirm the diagnosis. Acute pericarditis is usually self-limiting (2–6 weeks); therefore, management is conservative. If cardiac tamponade or constrictive pericarditis develops, cardiac output can be severely reduced. Treatment depends on the cause, but general measures include analgesics, anti-inflammatory drugs, colchicine, and rarely surgery.

MI is ischemia and death of an area of myocardial tissue due to insufficient blood flow and oxygenation, usually from thrombus formation on a ruptured atherosclerotic plaque in the epicardial arteries. Clinical presentation is most commonly with chest pain, but women and patients with diabetes may have atypical symptoms. Diagnosis is by clinical history, ECG changes, an increase in cardiac enzymes, and evidence of wall motion abnormalities on imaging. Management depends on the timing of the presentation and local resources with regard to thrombolytic therapy versus percutaneous intervention. All patients receive nitrates, pain control, aspirin, anticoagulation, and beta-blockers (unless contraindicated).

Examination of the cardiovascular system (CVS) is a critical component of a thorough physical examination. As with all components of a complete physical examination, the CVS examination consists of inspection, palpation, and auscultation. The evaluation of the CVS focuses on the heart, but also includes an assessment of the arterial system throughout the body. A number of cardiovascular conditions can be diagnosed with a physical examination, including valvular heart disease, peripheral artery disease, and arrhythmia.

Chest pain is one of the most common and challenging complaints that may present in an inpatient and outpatient setting. The differential diagnosis of chest pain is large and includes cardiac, gastrointestinal, pulmonary, musculoskeletal, and psychiatric etiologies. When you encounter a patient with chest pain, eliminating life-threatening causes, such as acute coronary syndrome (ACS) and pulmonary embolism, should be a priority. A thorough history and examination should be performed to narrow the differential diagnosis and guide diagnostic workup and management.

Pericardial effusion is the accumulation of excess fluid in the pericardial space around the heart. The pericardium does not easily expand; thus, rapid fluid accumulation leads to increased pressure around the heart. The increase in pressure restricts cardiac filling, resulting in decreased cardiac output and cardiac tamponade. Signs and symptoms usually occur in the setting of cardiac tamponade and include dyspnea, hypotension, muffled heart sounds, jugular venous distension, and pulsus paradoxus. The diagnosis of pericardial effusion is confirmed with echocardiography. Small effusions in stable patients are treated medically. Larger effusions and cardiac tamponade may require pericardiocentesis or pericardiotomy.

Pericarditis is an inflammation of the pericardium, often with fluid accumulation.  It can be caused by infection (often viral), myocardial infarction, drugs, malignancies, metabolic disorders, autoimmune disorders, or trauma.  Acute, subacute, and chronic forms exist.  Acute pericarditis is usually idiopathic and manifests as fever, pleuritic chest pain, and an audible pericardial rub by auscultation. Diffuse upwardly concave ST-segment elevations in the initial ECG and pericardial effusion on echocardiography confirm the diagnosis. Acute pericarditis is usually self-limiting (2–6 weeks); therefore, management is conservative. If cardiac tamponade or constrictive pericarditis develops, cardiac output can be severely reduced. Treatment depends on the cause, but general measures include analgesics, anti-inflammatory drugs, colchicine, and rarely surgery.