Yale-G Refined Clinical Review for the USMLE Step 2 CK

Chapter 2 CARDIOVASCULAR DISEASES IMPORTANT DIFFERENTIATIONS OF CHEST PAIN Chest pain is the most common symptom for most CVDs, respiratory diseases, and some upper abdominal diseases. Thus, it’s important to grasp the differential points. Angina and myocardial infarction (MI): See details on the same topic below. Myocarditis: It is usually preceded by a viral disease, with a vague chest pain. CK-MB is often increased. ECG (EKG) will show abnormal conduction or Q waves. Pericarditis: It may be preceded by a viral illness. Chest pain is sharp, pleuritic, and positional -- worse with lying down and relieved by sitting up; pericardial rub is often positive. ECG usually shows diffuse ST elevation without Q waves. CK is mostly normal. It responds well to anti-inflammatory drugs. Pleuritis: Mostly after lung infection; sharp chest pain worse on inspiration and certain position; tenderness, friction rub or dullness may be present. CXR or CT scan is the best means of diagnosis. Pneumonia: Moderate chest pain with fever, cough, sputum, and hemoptysis. CXR is the best test. Pneumothorax: Sudden, sharp, pleuritic chest pain and dyspnea; absent breath sounds; mediastinum shifted to the opposite site. Suspect of tension pneumothorax requires emergent intercostal needle puncture. Non-tension pneumothorax can wait for CXR confirmation and natural relief. Aortic (aneurysm) dissection: Very severe, sharp, tearing chest pain; typically radiating to the back; loss of pulses, unequal BP between arms, or aortic insufficiency; neurologic signs; widened mediastinum on CXR. MI may occur if dissection extends into coronary artery. Diagnosis is confirmed by TEE, CT scan, or aortography. Pulmonary embolism (PE): Sudden chest pain, dyspnea, tachycardia, cough, and hypoxemia, usually 3-5 days after a surgery or long immobility; pain is usually pleuritic but may resemble angina. LDH may be elevated. ECG is non-specific. CT pulmonary angiography has supplanted V/Q scanning as the preferred means of diagnosis. Mitral valve prolapse: Transient chest pain and typical midsystolic click murmur. Pulmonary hypertension: Dull chest pain with symptoms and signs of right ventricle (RV) failure. Costochondritis: Chest pain is usually stabbing, localized, and exacerbated with inspiration; reproducible or worse with chest palpation. ECG is normal.