Differential Diagnosis
The patient presents with chest pain, dizziness, dyspnea, fever, and nausea, along with a history of an upper respiratory tract infection. The physical exam and diagnostic findings provide crucial clues to the diagnosis.
Single Most Likely Diagnosis
- Cardiac Tamponade: The patient's presentation of chest pain, decreased breath sounds at the lung bases, pericardial friction rub, and a significant drop in blood pressure on inspiration (pulsus paradoxus) are highly suggestive of cardiac tamponade. The EKG showing electrical alternans further supports this diagnosis, as it is a classic sign of cardiac tamponade.
Other Likely Diagnoses
- Acute Pericarditis: Given the pericardial friction rub and the recent history of an upper respiratory tract infection, acute pericarditis is a plausible diagnosis. However, the presence of pulsus paradoxus and significant hypotension leans more towards cardiac tamponade.
- Pulmonary Embolism: Although less likely given the specific findings, pulmonary embolism could present with chest pain, dyspnea, and hypoxia. The absence of typical risk factors and the presence of a pericardial friction rub makes this less likely.
- Bacterial Endocarditis: This could be considered given the fever and new cardiac findings, but the acute presentation and specific signs of cardiac tamponade make it less likely.
Do Not Miss Diagnoses
- Aortic Dissection: Although the chest X-ray shows no abnormalities, aortic dissection is a critical diagnosis that must be considered in any patient with chest pain and hypotension. The absence of a typical tearing chest pain and the presence of other specific findings makes this less likely, but it should always be ruled out.
- Torsades de Pointes: Given the patient's hypoxia, hypotension, and potential for electrolyte imbalances, torsades de pointes is a rhythm disturbance that could occur and is life-threatening. However, the EKG provided does not specifically mention this rhythm.
Rare Diagnoses
- Mitral Valve Prolapse: While mitral valve prolapse can lead to acute presentations, the specific findings in this patient, such as the pericardial friction rub and pulsus paradoxus, do not typically align with mitral valve prolapse as a primary diagnosis.
- Other Cardiac Conditions: Various other cardiac conditions could present with similar symptoms, but given the specific findings, they are less likely and would be considered based on further evaluation and diagnostic testing.