INTERNAL MEDICINE COMAT EXAM / ACTUAL COMAT INTERNAL MEDICINE EXAM TEST BANK 2026/2027 PRACTICE QUESTIONS AND STUDY GUIDE

INTERNAL MEDICINE COMAT EXAM / ACTUAL COMAT INTERNAL MEDICINE EXAM TEST BANK 2026/2027 PRACTICE QUESTIONS AND STUDY GUIDE 1. A 68-year-old male presents with a 2-week history of progressive dyspnea on exertion, orthopnea, and paroxysmal nocturnal dyspnea. Physical examination reveals jugular venous distention, bibasilar crackles, and an S3 gallop. What is the most common cause of an S3 heart sound in an older adult? A) Aortic stenosis B) Hypertrophic cardiomyopathy C) Congestive heart failure D) Mitral regurgitation Correct Answer: C) Congestive heart failure Rationale: An S3 gallop occurs during early diastole due to rapid ventricular filling and is most commonly associated with congestive heart failure in older adults, though it can be a normal finding in children and young adults. An S3 in an older adult is a hallmark of elevated ventricular filling pressures and systolic heart failure. Aortic stenosis produces a systolic ejection murmur, hypertrophic cardiomyopathy typically causes a systolic murmur that increases with Valsalva, and mitral regurgitation is a holosystolic murmur. ________________________________________ 2. A 65-year-old man with a history of hypertension and myocardial infarction presents with progressive exertional dyspnea, orthopnea, and bilateral lower extremity edema. Physical exam reveals an S3 gallop and bibasilar crackles. What is the most likely diagnosis? A) Chronic obstructive pulmonary disease B) Congestive heart failure C) Pulmonary embolism D) Acute pericarditis Correct Answer: B) Congestive heart failure Rationale: The patient has classic signs of left-sided heart failure including orthopnea, crackles, S3 gallop, and peripheral edema. Prior MI and hypertension are major risk factors. COPD would present with wheezing and prolonged expiration, while PE is more acute and pericarditis typically presents with pleuritic chest pain and a pericardial friction rub. ________________________________________ 3. A 62-year-old woman with a history of hypertension presents with sudden onset of "tearing" chest pain radiating to the interscapular region. Her blood pressure is 180/100 mmHg in the right arm and 100/60 mmHg in the left arm. Which of the following is the most appropriate initial diagnostic study? A) Transthoracic echocardiogram B) CT angiography of the chest C) Chest X-ray D) Cardiac catheterization Correct Answer: B) CT angiography of the chest Rationale: The presentation is classic for acute aortic dissection, especially with the pulse differential and tearing pain. CT angiography is the preferred initial imaging study for suspected aortic dissection. Transthoracic echocardiography may miss a dissection of the descending aorta. Chest X-ray (widened mediastinum) is neither sensitive nor specific. Cardiac catheterization is not the first step and could be dangerous if the dissection involves the coronary ostia. ________________________________________ 4. A 65-year-old man presents to the emergency department with crushing substernal chest pain that radiates to his left arm, accompanied by diaphoresis and nausea. The pain began 2 hours ago. An ECG shows ST-segment elevation in leads V1–V4. Which of the following is the most appropriate immediate intervention? A) Administer sublingual nitroglycerin B) Start an IV infusion of alteplase C) Initiate dual antiplatelet therapy and arrange for immediate percutaneous coronary intervention (PCI) D) Give IV metoprolol to lower the heart rate Correct Answer: C) Initiate dual antiplatelet therapy and arrange for immediate percutaneous coronary intervention (PCI) Rationale: The patient presents with an acute ST-segment elevation myocardial infarction (STEMI). Primary PCI is the preferred reperfusion strategy when it can be performed within 90 minutes of presentation. If PCI is unavailable, IV thrombolytics would be considered; however, this is not the initial step. Dual antiplatelet therapy (aspirin plus a P2Y12 inhibitor) should be given as soon as the diagnosis is made. ________________________________________ 5. A 55-year-old male with a history of myocardial infarction presents with a diastolic decrescendo murmur best heard at the left upper sternal border. The murmur is most consistent with: A) Aortic stenosis B) Aortic regurgitation C) Mitral stenosis D) Pulmonic stenosis Correct Answer: B) Aortic regurgitation Rationale: Aortic regurgitation produces an early decrescendo diastolic murmur. It is best auscultated at the second left intercostal space (left upper sternal border) with the patient leaning forward and breath held in expiration. ________________________________________ 6. A patient presents with substernal chest pressure when walking two blocks, relieved with rest. ECG shows no ST changes. What is the most appropriate initial diagnostic test? A) Coronary angiography B) Exercise stress test (if patient can exercise and ECG interpretable) C) CT angiography D) Resting echocardiogram Correct Answer: B) Exercise stress test (if patient can exercise and ECG interpretable) Rationale: This presentation is consistent with stable angina. An exercise stress test is the appropriate initial diagnostic test for patients