50 Multiple-Choice Questions on Diagnosis of Simple Cardiac Diseases for Second-Year Medical Students
Question 1
A 45-year-old woman presents with retrosternal chest discomfort that builds gradually over 5 minutes during exercise. The pain radiates to her left arm and jaw. What is the most likely diagnosis?
A. Acute pericarditis
B. Angina pectoris
C. Musculoskeletal chest pain
D. Pulmonary embolism
Correct Answer: B
Explanation:
- B is correct: Angina pectoris presents as retrosternal chest discomfort that builds gradually over several minutes, is precipitated by physical or emotional stress, and characteristically radiates to the left arm, jaw, or shoulder 1.
- A is incorrect: Acute pericarditis typically causes sharp chest pain that worsens with inspiration and lying supine, not gradual onset with exertion 1.
- C is incorrect: Musculoskeletal pain can be localized to a specific point and is often positional, not exercise-induced with radiation 1.
- D is incorrect: Pulmonary embolism typically presents with sudden-onset dyspnea and pleuritic chest pain, not gradual exertional discomfort 2.
Pathophysiology: Angina occurs when myocardial oxygen demand exceeds supply due to coronary artery narrowing. During exercise, increased heart rate and contractility raise oxygen demand. Insufficient coronary blood flow causes myocardial ischemia, triggering pain receptors. The gradual onset reflects the time needed for metabolic byproducts (adenosine, lactate) to accumulate and stimulate cardiac sensory nerves 1.
Question 2
A 28-year-old man experiences sudden-onset "ripping" chest pain radiating to his back. He has a history of hypertension. What is the most concerning diagnosis?
A. Myocardial infarction
B. Aortic dissection
C. Pneumothorax
D. Esophageal spasm
Correct Answer: B
Explanation:
- B is correct: Sudden-onset ripping chest pain with radiation to the upper or lower back, especially in a hypertensive patient, is highly suspicious for acute aortic dissection 1, 3.
- A is incorrect: Myocardial infarction typically presents with gradual-onset pressure-like chest discomfort, not sudden ripping pain 1.
- C is incorrect: Pneumothorax causes sudden pleuritic chest pain and dyspnea but not the characteristic ripping quality with back radiation 2.
- D is incorrect: Esophageal spasm causes substernal discomfort but lacks the sudden ripping quality and back radiation 1.
Pathophysiology: Aortic dissection occurs when blood penetrates the intimal layer, creating a false lumen within the aortic wall. The sudden tearing of the intima causes immediate, severe pain. Hypertension increases wall stress, predisposing to intimal tears. The pain radiates along the path of dissection as it extends through the aorta 3, 4.
Question 3
During cardiac auscultation, you hear a holosystolic murmur at the apex radiating to the axilla. What valve abnormality is most likely?
A. Aortic stenosis
B. Mitral regurgitation
C. Tricuspid stenosis
D. Pulmonic regurgitation
Correct Answer: B
Explanation:
- B is correct: Mitral regurgitation produces a holosystolic (pansystolic) murmur best heard at the apex with radiation to the axilla. The murmur occurs throughout systole because the pressure gradient between the left ventricle and left atrium persists from early contraction until relaxation 5.
- A is incorrect: Aortic stenosis produces a midsystolic crescendo-decrescendo murmur, not holosystolic 5.
- C is incorrect: Tricuspid stenosis produces a diastolic murmur, not systolic 5.
- D is incorrect: Pulmonic regurgitation produces a diastolic murmur 5.
Pathophysiology: In mitral regurgitation, the incompetent mitral valve allows backward flow from the left ventricle to the left atrium during systole. Because left ventricular pressure greatly exceeds left atrial pressure throughout systole, regurgitant flow—and thus the murmur—persists from S1 to S2. The murmur radiates toward the axilla following the direction of the regurgitant jet 5.
Question 4
A 65-year-old man with dyspnea has a crescendo-decrescendo systolic murmur at the right upper sternal border radiating to the carotids. What is the most likely diagnosis?
A. Mitral stenosis
B. Aortic stenosis
C. Ventricular septal defect
D. Hypertrophic cardiomyopathy
Correct Answer: B
Explanation:
- B is correct: Aortic stenosis produces a midsystolic (systolic ejection) crescendo-decrescendo murmur best heard at the right upper sternal border with radiation to the carotid arteries 5.
- A is incorrect: Mitral stenosis produces a diastolic murmur with an opening snap, not a systolic murmur 5.
- C is incorrect: Ventricular septal defect produces a holosystolic murmur at the left lower sternal border, not crescendo-decrescendo 5.
- D is incorrect: While hypertrophic cardiomyopathy can produce a systolic murmur, it typically increases with Valsalva maneuver and is heard at the left sternal border 6.
Pathophysiology: Aortic stenosis narrows the aortic valve orifice, creating turbulent flow during ventricular ejection. The murmur starts after S1 when ventricular pressure rises sufficiently to open the stenotic valve. As ejection increases, the murmur intensifies (crescendo), then diminishes (decrescendo) as ejection declines. The murmur radiates along the path of turbulent blood flow toward the carotid arteries 5.
Question 5
A 22-year-old woman presents with sharp chest pain that worsens with inspiration and lying flat. She has a pericardial friction rub. What is the most likely diagnosis?
A. Acute myocardial infarction
B. Acute pericarditis
C. Pulmonary embolism
D. Pneumonia
Correct Answer: B
Explanation:
- B is correct: Acute pericarditis characteristically presents with sharp chest pain that increases with inspiration and lying supine, and is associated with a pericardial friction rub 1, 3.
- A is incorrect: Myocardial infarction typically causes pressure-like chest discomfort that does not vary with position or respiration 1.
- C is incorrect: Pulmonary embolism causes pleuritic chest pain but is not associated with a pericardial friction rub 2.
- D is incorrect: Pneumonia can cause pleuritic pain but produces lung findings (crackles, bronchial breath sounds), not a pericardial friction rub 1.
Pathophysiology: Pericarditis involves inflammation of the pericardial layers. The inflamed pericardium becomes roughened, and friction between the visceral and parietal layers during cardiac motion produces the characteristic rub. Pain worsens with inspiration because deep breathing increases pericardial movement. Lying supine increases contact between inflamed pericardial surfaces, intensifying pain 3.
Question 6
A patient presents with dyspnea. Echocardiography shows right atrial collapse and diastolic right ventricular collapse. What is the diagnosis?
A. Constrictive pericarditis
B. Cardiac tamponade
C. Restrictive cardiomyopathy
D. Pulmonary hypertension
Correct Answer: B
Explanation:
- B is correct: Right atrial collapse is sensitive, and diastolic right ventricular collapse is a more specific echocardiographic sign for cardiac tamponade 4.
- A is incorrect: Constrictive pericarditis shows pericardial thickening, ventricular interdependence, and respiratory variation in flow velocities, not chamber collapse 4.
- C is incorrect: Restrictive cardiomyopathy shows normal ventricular size with atrial enlargement and abnormal diastolic filling patterns, not chamber collapse 4, 6.
- D is incorrect: Pulmonary hypertension shows right ventricular hypertrophy and dilation, not chamber collapse 4.
Pathophysiology: Cardiac tamponade occurs when pericardial fluid accumulates rapidly, increasing intrapericardial pressure. When intrapericardial pressure exceeds right atrial pressure during diastole, the thin-walled right atrium collapses. As tamponade worsens and intrapericardial pressure exceeds right ventricular diastolic pressure, the right ventricle also collapses during diastole. These findings indicate hemodynamically significant tamponade requiring urgent intervention 4.
Question 7
A 55-year-old man with heart failure has distended neck veins that do not collapse with deep inspiration. What does this finding indicate?
A. Normal central venous pressure
B. Elevated central venous pressure
C. Hypovolemia
D. Left ventricular failure only
Correct Answer: B
Explanation:
- B is correct: Distention of the inferior vena cava (reflected by jugular venous distention) that does not collapse on deep inspiration indicates elevated central venous pressure 4.
- A is incorrect: Normal central venous pressure would show jugular veins that collapse with inspiration 4.
- C is incorrect: Hypovolemia would cause flat or barely visible jugular veins 4.
- D is incorrect: While left ventricular failure can eventually cause elevated central venous pressure through backward transmission, the finding specifically indicates elevated right-sided pressures 4.
Pathophysiology: Central venous pressure reflects right atrial pressure. Normally, inspiration creates negative intrathoracic pressure, increasing venous return and causing jugular veins to collapse. When central venous pressure is elevated (from right heart failure, tamponade, or constrictive pericarditis), the high baseline pressure prevents normal inspiratory collapse. This physical finding provides bedside assessment of right-sided filling pressures 4.
Question 8
A 70-year-old woman presents with dyspnea. Echocardiography shows normal left ventricular size and systolic function but marked atrial enlargement. What is the most likely diagnosis?
A. Dilated cardiomyopathy
B. Hypertrophic cardiomyopathy
C. Restrictive cardiomyopathy
D. Ischemic cardiomyopathy
Correct Answer: C
Explanation:
- C is correct: Restrictive cardiomyopathy characteristically shows normal ventricular size and wall thickness with normal systolic function, but marked atrial enlargement reflecting abnormal diastolic compliance 4, 6.
- A is incorrect: Dilated cardiomyopathy shows enlarged ventricles with reduced systolic function 6.
- B is incorrect: Hypertrophic cardiomyopathy shows ventricular hypertrophy, not normal wall thickness 6.
- D is incorrect: Ischemic cardiomyopathy typically shows regional wall motion abnormalities and reduced systolic function 4.
Pathophysiology: Restrictive cardiomyopathy involves infiltration or fibrosis of the myocardium, making the ventricles stiff and non-compliant. The ventricles cannot expand normally during diastole, causing elevated filling pressures. This backward pressure transmission causes marked atrial dilation. Systolic function remains preserved because the contractile apparatus is initially unaffected. The atria dilate to accommodate the increased pressure required to fill the stiff ventricles 6.
Question 9
A patient with suspected heart failure has an ejection fraction of 55%. What type of heart failure is this?
A. Systolic heart failure
B. Diastolic heart failure
C. High-output heart failure
D. Right heart failure
Correct Answer: B
Explanation:
- B is correct: Heart failure with an ejection fraction >40% (typically >50%) is classified as heart failure with preserved ejection fraction, also known as diastolic dysfunction or diastolic heart failure 4.
- A is incorrect: Systolic heart failure is characterized by reduced ejection fraction (typically <40%) 4.
- C is incorrect: High-output heart failure refers to heart failure in the setting of increased cardiac output (e.g., thyrotoxicosis, anemia), not a specific ejection fraction category 5.
- D is incorrect: Right heart failure refers to the affected chamber, not the mechanism of dysfunction 4.
Pathophysiology: Diastolic heart failure occurs when the ventricle cannot relax and fill properly despite normal contractile function. Causes include hypertrophy, fibrosis, or infiltrative disease that stiffen the myocardium. The stiff ventricle requires higher filling pressures, causing backward transmission of pressure to the pulmonary circulation and systemic veins, producing heart failure symptoms despite preserved systolic function 4.
Question 10
A 30-year-old athlete has a systolic murmur that increases in intensity with Valsalva maneuver. What is the most likely diagnosis?
A. Aortic stenosis
B. Mitral regurgitation
C. Hypertrophic cardiomyopathy
D. Innocent flow murmur
Correct Answer: C
Explanation:
- C is correct: Hypertrophic cardiomyopathy produces a systolic murmur that characteristically increases with Valsalva maneuver or standing (maneuvers that decrease preload) 6.
- A is incorrect: Aortic stenosis murmur typically decreases with Valsalva maneuver due to reduced stroke volume 5.
- B is incorrect: Mitral regurgitation murmur typically decreases with Valsalva maneuver 5.
- D is incorrect: Innocent flow murmurs decrease or disappear with Valsalva maneuver 5.
Pathophysiology: In hypertrophic cardiomyopathy, asymmetric septal hypertrophy narrows the left ventricular outflow tract. During systole, the anterior mitral valve leaflet is drawn toward the hypertrophied septum (systolic anterior motion), worsening obstruction. Valsalva maneuver reduces venous return and left ventricular volume, bringing the mitral valve closer to the septum and increasing obstruction, thus intensifying the murmur 6.
Question 11
A patient presents with fleeting chest pain lasting only 3-4 seconds. Is this likely cardiac ischemia?
A. Yes, typical of unstable angina
B. Yes, typical of variant angina
C. No, too brief for ischemic pain
D. Yes, typical of myocardial infarction
Correct Answer: C
Explanation:
- C is correct: Fleeting chest pain of only a few seconds' duration is unlikely to be related to ischemic heart disease 1.
- A is incorrect: Unstable angina typically lasts several minutes 1.
- B is incorrect: Variant (Prinzmetal's) angina also lasts several minutes 1.
- D is incorrect: Myocardial infarction pain typically lasts >20 minutes 1.
Pathophysiology: Myocardial ischemia requires time for metabolic changes to occur. When coronary blood flow is insufficient, anaerobic metabolism produces lactate and other metabolites that accumulate and stimulate pain receptors. This process takes several minutes. Pain lasting only seconds is too brief for ischemic metabolite accumulation and more likely represents musculoskeletal, neurologic, or other non-cardiac causes 1.
Question 12
A 50-year-old man has chest pain that can be reproduced by pressing on a specific point on his chest wall. What is the most likely diagnosis?
A. Acute coronary syndrome
B. Musculoskeletal chest pain
C. Pericarditis
D. Aortic dissection
Correct Answer: B
Explanation:
- B is correct: Chest pain that can be localized to a very limited area and reproduced by palpation is characteristic of musculoskeletal chest pain 1, 7.
- A is incorrect: Acute coronary syndrome produces diffuse retrosternal discomfort that cannot be reproduced by palpation 1.
- C is incorrect: Pericarditis causes positional pain but is not typically reproducible by chest wall palpation 1.
- D is incorrect: Aortic dissection causes severe ripping pain that cannot be reproduced by palpation 1.
Pathophysiology: Musculoskeletal chest pain arises from inflammation or injury to the chest wall structures (ribs, cartilage, muscles, or intercostal tissues). Local inflammation causes pain receptors in these structures to become sensitized. Direct pressure on the inflamed area mechanically stimulates these receptors, reproducing the pain. This localized, reproducible nature distinguishes musculoskeletal pain from cardiac causes 7.
Question 13
A patient with chest pain has relief after taking nitroglycerin. Does this confirm cardiac ischemia?
A. Yes, nitroglycerin relief is diagnostic of ischemia
B. No, nitroglycerin relief is not diagnostic
C. Yes, only cardiac pain responds to nitroglycerin
D. No, but it makes ischemia very unlikely
Correct Answer: B
Explanation:
- B is correct: Relief with nitroglycerin is not necessarily diagnostic of myocardial ischemia and should not be used as a diagnostic criterion 1.
- A is incorrect: Nitroglycerin can relieve esophageal spasm and other non-cardiac chest pain 1.
- C is incorrect: Non-cardiac conditions (especially esophageal disorders) can respond to nitroglycerin 1.
- D is incorrect: Lack of response to nitroglycerin does not rule out ischemia, and response does not confirm it 1.
Pathophysiology: Nitroglycerin causes smooth muscle relaxation through nitric oxide release. While it dilates coronary arteries and reduces myocardial oxygen demand (relieving angina), it also relaxes esophageal smooth muscle, potentially relieving esophageal spasm. This non-specific mechanism explains why nitroglycerin response cannot distinguish cardiac from non-cardiac chest pain 1.
Question 14
A 60-year-old woman presents with dyspnea. When should echocardiography be performed?
A. Only if chest X-ray is abnormal
B. When distinguishing cardiac vs. non-cardiac causes is unclear
C. Only if troponin is elevated
D. Never as first-line test
Correct Answer: B
Explanation:
- B is correct: Echocardiography is recommended for distinguishing cardiac vs. non-cardiac etiology of dyspnea when clinical and laboratory findings are ambiguous 2.
- A is incorrect: Echocardiography provides functional information not available on chest X-ray and is indicated even with normal radiographs 2.
- C is incorrect: Troponin elevation indicates myocardial injury but echocardiography is useful for dyspnea evaluation regardless of troponin levels 2.
- D is incorrect: Echocardiography is a first-line test for evaluating cardiac causes of dyspnea 2.
Pathophysiology: Dyspnea can result from cardiac causes (heart failure, valvular disease, pericardial disease) or non-cardiac causes (pulmonary disease, anemia, deconditioning). Echocardiography directly visualizes cardiac structure and function, assessing ventricular size, systolic and diastolic function, valvular abnormalities, and pericardial disease. This comprehensive cardiac assessment helps distinguish cardiac from non-cardiac dyspnea when clinical evaluation is inconclusive 2.
Question 15
A patient in shock has hypotension unresponsive to fluids. What is the role of emergency echocardiography?
A. Not indicated in shock
B. Only if cardiac arrest occurs
C. Rapid differential diagnosis of shock etiology
D. Only after stabilization
Correct Answer: C
Explanation:
- C is correct: Emergency echocardiography is recommended for differential diagnosis of hypotension or shock by detecting cardiac or non-cardiac etiologies 2.
- A is incorrect: Echocardiography is specifically indicated in shock for rapid diagnosis 2.
- B is incorrect: Echocardiography should be performed before cardiac arrest to guide management 2.
- D is incorrect: Emergency echocardiography should be performed urgently to guide resuscitation, not delayed until after stabilization 2.
Pathophysiology: Shock represents inadequate tissue perfusion from various causes: cardiogenic (pump failure), hypovolemic (inadequate preload), distributive (vasodilation), or obstructive (mechanical obstruction). Echocardiography rapidly distinguishes these by assessing: ventricular function (cardiogenic), chamber size and IVC collapse (hypovolemic), pericardial effusion (tamponade), and right ventricular strain (pulmonary embolism). This immediate diagnostic information guides specific treatment 2.
Question 16
A patient develops a new cardiac murmur with fever and positive blood cultures. What should be evaluated by echocardiography?
A. Only if heart failure develops
B. Valvular vegetations indicating endocarditis
C. Only if murmur is diastolic
D. Not indicated with positive blood cultures
Correct Answer: B
Explanation:
- B is correct: Echocardiography is recommended for detection of valvular vegetations indicating infective endocarditis in patients with cardiac murmurs and clinical evidence suggesting endocarditis 2.
- A is incorrect: Echocardiography should be performed when endocarditis is suspected, not delayed until complications develop 2.
- C is incorrect: Both systolic and diastolic murmurs warrant evaluation in suspected endocarditis 2.
- D is incorrect: Positive blood cultures with a new murmur strongly suggest endocarditis and require echocardiographic evaluation 2.
Pathophysiology: Infective endocarditis occurs when bacteria colonize damaged or abnormal heart valves, forming vegetations (infected masses of bacteria, fibrin, and platelets). These vegetations damage valve leaflets, causing regurgitation and producing new murmurs. Echocardiography visualizes vegetations and assesses valve damage severity. Early detection guides antibiotic therapy and identifies patients requiring surgical intervention 2.
Question 17
A patient with chest trauma and hypotension requires echocardiography. What findings are being sought?
A. Only pericardial effusion
B. Pericardial effusion, myocardial contusion, and valvular injury
C. Only if ECG is abnormal
D. Not indicated in trauma
Correct Answer: B
Explanation:
- B is correct: Echocardiography in chest trauma detects pericardial effusion, myocardial contusion or laceration, regional wall motion abnormalities, acute valvular regurgitation, and aortic dissection 2.
- A is incorrect: Multiple cardiac injuries beyond pericardial effusion must be evaluated 2.
- C is incorrect: Echocardiography is indicated in severe chest trauma regardless of ECG findings 2.
- D is incorrect: Echocardiography is specifically recommended in severe chest trauma 2.
Pathophysiology: Blunt chest trauma can cause multiple cardiac injuries. Direct impact causes myocardial contusion (bruising) with regional dysfunction. Severe trauma can lacerate the myocardium or rupture valves. Rapid deceleration can tear the aorta. Pericardial bleeding causes tamponade. Echocardiography rapidly identifies these life-threatening injuries, guiding urgent surgical or medical intervention 2.
Question 18
During CPR, when is echocardiography indicated?
A. Routinely during all CPR
B. To identify unexpected causes of arrest without interfering with CPR
C. Only after return of spontaneous circulation
D. Never during active resuscitation
Correct Answer: B
Explanation:
- B is correct: Echocardiography during CPR is recommended for identification of unexpected causes of cardiac arrest (tamponade, pulmonary embolism, hypovolemia) to guide CPR, but should not interfere with CPR 2.
- A is incorrect: Echocardiography is not recommended as a routine procedure during CPR if it interferes with resuscitation 2.
- C is incorrect: Echocardiography can be valuable during CPR to identify treatable causes 2.
- D is incorrect: Echocardiography is specifically indicated during CPR when it can identify reversible causes 2.
Pathophysiology: Cardiac arrest can result from reversible causes (the "H's and T's"): hypovolemia, tamponade, tension pneumothorax, pulmonary embolism, among others. Echocardiography during brief pauses in compressions can identify these treatable causes. For example, visualizing a large pericardial effusion prompts immediate pericardiocentesis, or seeing a dilated, akinetic right ventricle suggests massive pulmonary embolism requiring thrombolysis 2.
Question 19
A patient has constrictive pericarditis. What Doppler finding is characteristic?
A. Fixed splitting of S2
B. Exaggerated respiratory variation in atrioventricular valve flow
C. Continuous murmur
D. No Doppler abnormalities
Correct Answer: B
Explanation:
- B is correct: Doppler findings of exaggerated respiratory variation in flow velocities across the atrioventricular valves as well as LV outflow and pulmonary venous flow are highly characteristic of constrictive pericarditis 4.
- A is incorrect: Fixed splitting of S2 is characteristic of atrial septal defect, not constrictive pericarditis 5.
- C is incorrect: Continuous murmurs are not features of constrictive pericarditis 5.
- D is incorrect: Constrictive pericarditis has characteristic Doppler abnormalities 4.
Pathophysiology: In constrictive pericarditis, the rigid pericardium limits total cardiac volume. During inspiration, increased venous return fills the right heart, but the fixed pericardial volume forces the interventricular septum leftward, reducing left ventricular filling. This causes exaggerated respiratory variation in flow velocities: mitral inflow velocity decreases >25% with inspiration while tricuspid inflow increases. This ventricular interdependence is the hallmark of constriction 4.
Question 20
A patient has pericardial effusion. What echocardiographic finding indicates hemodynamically significant tamponade?
A. Any visible effusion
B. Diastolic right ventricular collapse
C. Left atrial enlargement
D. Mitral regurgitation
Correct Answer: B
Explanation:
- B is correct: Diastolic right ventricular collapse is a more specific echocardiographic sign for hemodynamically significant cardiac tamponade 4.
- A is incorrect: Small pericardial effusions can be present without tamponade 4.
- C is incorrect: Left atrial enlargement is not a sign of tamponade 4.
- D is incorrect: Mitral regurgitation is not a specific sign of tamponade 4.
Pathophysiology: Cardiac tamponade occurs when pericardial pressure exceeds intracardiac pressures. The right ventricle, having the lowest diastolic pressure, is affected first. When pericardial pressure exceeds right ventricular diastolic pressure, the free wall collapses inward during diastole. This finding indicates that pericardial pressure is critically elevated and cardiac output is compromised, requiring urgent pericardiocentesis 4.
Question 21
A 35-year-old woman presents with palpitations and lightheadedness during exercise. What historical feature suggests ventricular arrhythmia?
A. Palpitations only at rest
B. Exercise or emotional stress as precipitating factors
C. Relief with Valsalva maneuver
D. Palpitations lasting <1 second
Correct Answer: B
Explanation:
- B is correct: Precipitating factors such as exercise or emotional stress are important historical features suggesting ventricular arrhythmia 8.
- A is incorrect: While arrhythmias can occur at rest, exercise-induced symptoms are more concerning for ventricular arrhythmias 8.
- C is incorrect: Valsalva maneuver may terminate supraventricular tachycardia but does not reliably affect ventricular arrhythmias 8.
- D is incorrect: Brief palpitations are less concerning than sustained symptoms with exercise 8.
Pathophysiology: Exercise increases sympathetic tone and myocardial oxygen demand. In patients with underlying cardiac disease or channelopathies, exercise can trigger ventricular arrhythmias through increased catecholamines, electrolyte shifts, or ischemia. Emotional stress similarly increases catecholamines. Exercise-induced symptoms are particularly concerning because they suggest arrhythmias occurring during increased cardiac demand, raising sudden cardiac death risk 8.
Question 22
A patient's family history includes sudden cardiac death in a first-degree relative at age 30. What does this suggest?
A. No increased risk for the patient
B. Possible inherited cardiac condition requiring evaluation
C. Only relevant if patient has symptoms
D. Only relevant for coronary artery disease
Correct Answer: B
Explanation:
- B is correct: Family history of sudden cardiac death in a first-degree relative suggests possible inherited cardiac conditions (cardiomyopathy, channelopathies) requiring evaluation 8.
- A is incorrect: Family history of sudden cardiac death significantly increases the patient's risk 8.
- C is incorrect: Evaluation is warranted even in asymptomatic patients with this family history 8.
- D is incorrect: Sudden cardiac death in young relatives suggests inherited conditions beyond coronary disease 8.
Pathophysiology: Many cardiac conditions causing sudden death are inherited: hypertrophic cardiomyopathy (autosomal dominant), long QT syndrome (genetic channelopathy), arrhythmogenic right ventricular cardiomyopathy, and others. First-degree relatives share 50% of genes, conferring significant risk. Early identification through family screening allows preventive interventions (medications, ICDs) before symptoms or sudden death occur 8.
Question 23
A patient on multiple medications develops syncope. What medication effect should be considered?
A. All medications are safe regarding arrhythmias
B. QT prolongation and torsades de pointes risk
C. Only antiarrhythmic drugs cause arrhythmias
D. Medication effects are irrelevant to syncope
Correct Answer: B
Explanation:
- B is correct: Various antiarrhythmic and other medications can cause QT prolongation and torsades de pointes, and medication-medication interactions can also cause these effects 8.
- A is incorrect: Many medications have proarrhythmic effects 8.
- C is incorrect: Non-antiarrhythmic medications (antibiotics, antipsychotics, antiemetics) can prolong QT 8.
- D is incorrect: Medication effects are a critical consideration in syncope evaluation 8.
Pathophysiology: Many medications block cardiac potassium channels (particularly IKr), prolonging ventricular repolarization and the QT interval. Prolonged QT creates electrical heterogeneity in the myocardium, predisposing to early afterdepolarizations. These can trigger torsades de pointes, a polymorphic ventricular tachycardia causing syncope or sudden death. Drug-drug interactions can amplify this effect by inhibiting medication metabolism 8.
Question 24
A patient has bigeminy on examination. What physical finding might be present?
A. Tachycardia
B. Effective bradycardia with pulse deficit
C. Hypertension with narrow pulse pressure
D. Regular pulse
Correct Answer: B
Explanation:
- B is correct: Patients with bigeminy can present with effective bradycardia and an apical-radial pulse deficit 8.
- A is incorrect: Bigeminy typically causes effective bradycardia, not tachycardia 8.
- C is incorrect: Bigeminy causes wide pulse pressure, not narrow 8.
- D is incorrect: Bigeminy produces an irregular pulse pattern 8.
Pathophysiology: Bigeminy is a pattern where every other beat is a premature ventricular contraction (PVC). PVCs occur early when the ventricle is incompletely filled, producing weak contractions with low stroke volume. These beats may not generate sufficient pressure to open the aortic valve or produce a palpable peripheral pulse. The effective heart rate is thus half the actual rate (only normal beats produce pulses), creating effective bradycardia and pulse deficit 8.
Question 25
A patient presents with dyspnea and orthopnea. What do these symptoms suggest?
A. Pulmonary disease only
B. Possible heart failure requiring cardiac evaluation
C. Normal findings
D. Anxiety disorder
Correct Answer: B
Explanation:
- B is correct: Dyspnea and orthopnea are symptoms related to heart failure that warrant cardiac evaluation 8.
- A is incorrect: While pulmonary disease causes dyspnea, orthopnea specifically suggests cardiac causes 8.
- C is incorrect: These are abnormal symptoms requiring evaluation 8.
- D is incorrect: While anxiety can cause dyspnea, orthopnea suggests organic cardiac or pulmonary disease 8.
Pathophysiology: Heart failure causes pulmonary congestion from elevated left atrial pressure transmitted backward to pulmonary veins and capillaries. Dyspnea results from stiff, fluid-filled lungs requiring increased work of breathing and from stimulation of pulmonary stretch receptors. Orthopnea (dyspnea when lying flat) occurs because the supine position redistributes fluid from the legs to the thorax, worsening pulmonary congestion. Patients typically sleep propped up on pillows 8.
Question 26
A patient has a murmur and symptoms of heart failure. When is echocardiography indicated?
A. Only if the murmur is loud
B. In patients with murmurs and symptoms suggesting heart failure
C. Only if chest X-ray shows cardiomegaly
D. Never for murmur evaluation
Correct Answer: B
Explanation:
- B is correct: Echocardiography is indicated in patients with cardiac murmurs and symptoms or signs suggestive of heart failure 2.
- A is incorrect: Murmur intensity does not determine the need for echocardiography; symptoms do 2.
- C is incorrect: Echocardiography is indicated based on clinical findings, not chest X-ray results 2.
- D is incorrect: Echocardiography is the primary method for evaluating murmurs with associated symptoms 2.
Pathophysiology: Cardiac murmurs indicate turbulent blood flow from valvular disease, structural abnormalities, or high-flow states. When accompanied by heart failure symptoms, murmurs suggest hemodynamically significant valve disease. Echocardiography directly visualizes valve structure, quantifies stenosis or regurgitation severity, and assesses ventricular function. This information determines whether valve disease is causing symptoms and guides medical or surgical management 2.
Question 27
A patient has acute chest pain with non-diagnostic ECG and cardiac biomarkers. When should echocardiography be performed?
A. Never, only if ECG is diagnostic
B. When the echocardiogram can be performed during pain
C. Only after 24 hours
D. Only if troponin becomes positive
Correct Answer: B
Explanation:
- B is correct: Echocardiography is recommended for evaluation of acute chest pain in patients with suspected myocardial ischemia, non-diagnostic ECG and cardiac biomarkers, when resting echocardiogram can be performed during the pain 3.
- A is incorrect: Echocardiography is specifically useful when ECG is non-diagnostic 3.
- C is incorrect: Echocardiography should be performed during pain to detect ischemia-induced wall motion abnormalities 3.
- D is incorrect: Echocardiography is valuable before biomarkers become positive 3.
Pathophysiology: Myocardial ischemia causes regional wall motion abnormalities within seconds, before ECG changes or biomarker elevation. Echocardiography performed during chest pain can detect these abnormalities, identifying ischemia when other tests are non-diagnostic. The ischemic region becomes hypokinetic or akinetic due to insufficient oxygen for normal contraction. This finding helps risk-stratify patients and guide urgent intervention 3.
Question 28
A patient has suspected Takotsubo cardiomyopathy. What echocardiographic finding is typical?
A. Diffuse hypokinesis
B. Left ventricular apical akinesia with basal sparing
C. Right ventricular dilation only
D. Normal echocardiogram
Correct Answer: B
Explanation:
- B is correct: The typical case of Takotsubo cardiomyopathy presents with left ventricular apical akinesia, making echocardiography an ideal diagnostic tool 3.
- A is incorrect: Takotsubo shows regional, not diffuse, wall motion abnormalities 3.
- C is incorrect: While RV involvement can occur, the classic finding is LV apical akinesia 3.
- D is incorrect: Takotsubo shows characteristic wall motion abnormalities 3.
Pathophysiology: Takotsubo cardiomyopathy is stress-induced, transient LV dysfunction. Excessive catecholamine release causes direct myocardial toxicity and microvascular dysfunction, predominantly affecting the apex (which has higher β-adrenergic receptor density). The apex becomes akinetic while the base contracts normally, creating a characteristic "ballooning" appearance. Unlike myocardial infarction, the dysfunction doesn't follow coronary territories and completely recovers within days to weeks 3.
Question 29
A patient with suspected aortic dissection requires urgent imaging. What is the role of echocardiography?
A. Not useful for aortic dissection
B. Initial imaging modality in the emergency setting
C. Only after CT or MRI
D. Only for chronic dissection
Correct Answer: B
Explanation:
- B is correct: Echocardiography is recommended as an initial imaging modality for diagnosis of suspected aortic dissection in the emergency setting 2.
- A is incorrect: Echocardiography (especially TEE) is highly effective for diagnosing aortic dissection 3, 4.
- C is incorrect: Echocardiography can be the first imaging test, particularly TEE 2.
- D is incorrect: Echocardiography is specifically valuable in acute dissection 3.
Pathophysiology: Aortic dissection creates an intimal flap separating true and false lumens. Transthoracic echocardiography can visualize proximal ascending aorta dissections and associated complications (aortic regurgitation, pericardial effusion). Transesophageal echocardiography provides superior visualization of the entire thoracic aorta. Rapid bedside diagnosis is critical because ascending aortic dissection requires emergency surgery, while descending dissection is often managed medically 3, 4.
Question 30
A patient has hypertrophic cardiomyopathy. What does echocardiography assess?
A. Only wall thickness
B. Morphology, obstruction severity, and mitral regurgitation
C. Only systolic function
D. Only diastolic function
Correct Answer: B
Explanation:
- B is correct: Echocardiography establishes the diagnosis by revealing hypertrophy and permits comprehensive morphologic assessment. Doppler techniques assess severity of intraventricular obstruction and associated mitral regurgitation and diastolic filling abnormalities 6.
- A is incorrect: Echocardiography provides comprehensive assessment beyond wall thickness 6.
- C is incorrect: Multiple parameters are assessed, not just systolic function 6.
- D is incorrect: Both systolic and diastolic parameters are evaluated 6.
Pathophysiology: Hypertrophic cardiomyopathy involves asymmetric septal hypertrophy causing LV outflow tract obstruction. Echocardiography measures wall thickness, identifies obstruction location, and quantifies the pressure gradient using Doppler. Systolic anterior motion of the mitral valve worsens obstruction and causes mitral regurgitation. Diastolic dysfunction results from the stiff, hypertrophied myocardium. Comprehensive assessment guides treatment (medications, septal reduction) 6.
Question 31
A patient has edema and elevated jugular venous pressure. When is echocardiography indicated?
A. Never for edema
B. When cardiac etiology is suspected or CVP assessment is uncertain
C. Only if liver disease is excluded
D. Only if BNP is elevated
Correct Answer: B
Explanation:
- B is correct: Echocardiography is indicated for edema with clinical signs of elevated central venous pressure when a potential cardiac etiology is suspected or when central venous pressure cannot be estimated with confidence and clinical suspicion of heart disease is high 4.
- A is incorrect: Edema can result from cardiac causes requiring echocardiographic evaluation 4.
- C is incorrect: Echocardiography helps distinguish cardiac from non-cardiac causes of edema 4.
- D is incorrect: Echocardiography is indicated based on clinical findings, not solely on BNP levels 4.
Pathophysiology: Edema results from elevated venous pressure causing fluid extravasation into tissues. Cardiac causes include right heart failure (elevated right atrial pressure) or biventricular failure. Elevated jugular venous pressure indicates elevated right atrial pressure. Echocardiography identifies the cardiac cause: right ventricular dysfunction, tricuspid regurgitation, pericardial disease, or left heart disease with secondary right heart involvement. This guides specific treatment 4.
Question 32
A patient has suspected pulmonary embolism with hemodynamic instability. What is the role of echocardiography?
A. Not useful for pulmonary embolism
B. Guide therapeutic approach (thrombectomy, thrombolytics)
C. Only to rule out pulmonary embolism
D. Only in stable patients
Correct Answer: B
Explanation:
- B is correct: Echocardiography is recommended for guiding the therapeutic approach in patients with known pulmonary embolism (e.g., thrombectomy and thrombolytics) 2.
- A is incorrect: Echocardiography provides valuable information in pulmonary embolism 2.
- C is incorrect: Echocardiography cannot reliably rule out PE but guides treatment in confirmed cases 2.
- D is incorrect: Echocardiography is particularly valuable in unstable patients with PE 2.
Pathophysiology: Massive pulmonary embolism obstructs pulmonary arteries, increasing right ventricular afterload. The RV dilates and becomes hypokinetic from acute pressure overload. Echocardiography shows RV dilation, RV dysfunction, septal flattening (D-sign), and elevated RV systolic pressure. These findings indicate hemodynamically significant PE requiring aggressive treatment (thrombolysis, thrombectomy). Echocardiography guides risk stratification and treatment decisions 2.
Question 33
A patient has pericardial effusion requiring drainage. What is the role of echocardiography?
A. Only for diagnosis, not for procedures
B. Guidance and monitoring of pericardiocentesis
C. Only after pericardiocentesis
D. Not useful for procedures
Correct Answer: B
Explanation:
- B is correct: Echocardiography is indicated for guidance and monitoring of pericardiocentesis 2, 4.
- A is incorrect: Echocardiography is valuable for both diagnosis and procedural guidance 4.
- C is incorrect: Echocardiography guides the procedure in real-time 4.
- D is incorrect: Echocardiography is specifically useful for procedural guidance 4.
Pathophysiology: Pericardiocentesis involves inserting a needle through the chest wall into the pericardial space to drain fluid. Echocardiography identifies the optimal entry site (where fluid is closest to the chest wall), guides needle trajectory in real-time, confirms needle position in the pericardial space, and monitors for complications (myocardial puncture, pneumothorax). This guidance significantly improves safety and success rates 4.
Question 34
A patient has acute myocarditis. What echocardiographic findings might be present?
A. Always normal echocardiogram
B. Regional wall motion abnormalities and reduced systolic function
C. Only pericardial effusion
D. Only diastolic dysfunction
Correct Answer: B
Explanation:
- B is correct: Acute myocarditis can show regional or global wall motion abnormalities, reduced LV systolic function, and ventricular wall thickening from myocardial edema 3.
- A is incorrect: Myocarditis typically shows echocardiographic abnormalities 3.
- C is incorrect: While pericardial effusion can occur (myopericarditis), myocardial dysfunction is the primary finding 3.
- D is incorrect: Both systolic and diastolic dysfunction can occur 3.
Pathophysiology: Myocarditis involves myocardial inflammation from viral infection, autoimmune disease, or toxins. Inflammatory infiltrates damage myocytes, causing regional or global contractile dysfunction. Interstitial edema thickens the ventricular wall. Severe cases progress to dilated cardiomyopathy. Echocardiography detects these changes, distinguishing myocarditis from ischemic heart disease (myocarditis doesn't follow coronary territories). Speckle tracking can detect subtle dysfunction 3.
Question 35
A patient has suspected infective endocarditis. When is transesophageal echocardiography indicated?
A. Never, TTE is always sufficient
B. When TTE is non-diagnostic
C. Only for prosthetic valves
D. Only after treatment completion
Correct Answer: B
Explanation:
- B is correct: TEE is indicated when TTE studies are non-diagnostic in suspected endocarditis 2.
- A is incorrect: TTE has limited sensitivity for small vegetations and prosthetic valve endocarditis 2.
- C is incorrect: TEE is indicated whenever TTE is inadequate, not only for prosthetic valves 2.
- D is incorrect: TEE is performed during diagnosis, not only after treatment 2.
Pathophysiology: Transthoracic echocardiography has limited resolution for small vegetations (<5mm) and poor visualization of prosthetic valves due to acoustic shadowing. Transesophageal echocardiography provides superior resolution because the esophagus is adjacent to the heart, eliminating chest wall interference. TEE detects smaller vegetations, valve perforations, and abscesses. This improved sensitivity is critical for diagnosis and surgical planning in endocarditis 2.
Question 36
A patient has chest pain radiating below the umbilicus. Is this likely cardiac?
A. Yes, typical of inferior MI
B. No, unlikely related to myocardial ischemia
C. Yes, typical of unstable angina
D. Yes, typical of pericarditis
Correct Answer: B
Explanation:
- B is correct: Pain radiating below the umbilicus or to the hip is unlikely related to myocardial ischemia 1.
- A is incorrect: Inferior MI causes chest pain but not radiation below the umbilicus 1.
- C is incorrect: Unstable angina has typical radiation patterns (arm, jaw, shoulder), not below umbilicus 1.
- D is incorrect: Pericarditis causes positional chest pain without radiation below the umbilicus 1.
Pathophysiology: Cardiac pain is referred through visceral afferent nerves entering the spinal cord at T1-T5 levels, corresponding to dermatomes of the chest, arms, jaw, and upper back. Pain below the umbilicus corresponds to lower thoracic and lumbar dermatomes, which do not receive cardiac afferents. Pain in these areas suggests gastrointestinal, genitourinary, or musculoskeletal origins, not cardiac ischemia 1.
Question 37
A patient has positional chest pain that worsens when leaning forward. What is the likely diagnosis?
A. Acute coronary syndrome
B. Musculoskeletal pain
C. Pulmonary embolism
D. Aortic dissection
Correct Answer: B
Explanation:
- B is correct: Positional chest pain is usually nonischemic and suggests musculoskeletal origin 1.
- A is incorrect: Acute coronary syndrome pain does not vary with position 1.
- C is incorrect: Pulmonary embolism causes pleuritic pain (worse with breathing), not positional pain 1.
- D is incorrect: Aortic dissection causes constant severe pain unaffected by position 1.
Pathophysiology: Musculoskeletal chest pain arises from chest wall structures (ribs, cartilage, muscles, joints). Position changes alter mechanical stress on these structures. Leaning forward stretches or compresses inflamed tissues, reproducing pain. Cardiac pain originates from myocardial ischemia and is unaffected by body position. This distinction helps differentiate musculoskeletal from cardiac causes 1.
Question 38
A patient has dyspnea that worsens at night when lying flat (orthopnea). What is the pathophysiologic mechanism?
A. Increased venous return worsening pulmonary congestion
B. Decreased cardiac output
C. Bronchospasm
D. Anxiety
Correct Answer: A
Explanation:
- A is correct: Orthopnea occurs because the supine position redistributes fluid from the legs to the thorax, increasing venous return and worsening pulmonary congestion in heart failure 8.
- B is incorrect: While cardiac output may be reduced in heart failure, orthopnea specifically results from increased venous return 8.
- C is incorrect: Bronchospasm causes dyspnea but doesn't explain the positional component 8.
- D is incorrect: Anxiety doesn't cause true orthopnea 8.
Pathophysiology: In heart failure, elevated left atrial pressure causes pulmonary venous congestion. When upright, gravity pools blood in the legs, reducing venous return and pulmonary congestion. Lying flat eliminates this gravitational effect, increasing venous return to the heart. The failing left ventricle cannot accommodate this increased preload, causing further elevation of left atrial pressure and worsening pulmonary edema, producing dyspnea 8.
Question 39
A patient has paroxysmal nocturnal dyspnea (PND). What distinguishes this from orthopnea?
A. PND occurs immediately upon lying down
B. PND occurs 1-2 hours after falling asleep
C. PND is less severe than orthopnea
D. PND is not related to heart failure
Correct Answer: B
Explanation:
- B is correct: Paroxysmal nocturnal dyspnea occurs 1-2 hours after falling asleep, waking the patient with severe dyspnea, distinguishing it from orthopnea which occurs immediately upon lying down.
- A is incorrect: Immediate dyspnea upon lying down is orthopnea, not PND.
- C is incorrect: PND is typically more severe, causing the patient to wake gasping for air.
- D is incorrect: PND is a classic symptom of heart failure.
Pathophysiology: After falling asleep supine, fluid gradually redistributes from the interstitium to the vascular space, increasing venous return over 1-2 hours. Additionally, respiratory drive decreases during sleep. These factors combine to worsen pulmonary congestion. The patient awakens suddenly with severe dyspnea and must sit upright or stand. This represents more advanced heart failure than simple orthopnea.
Question 40
A patient has a continuous murmur throughout systole and diastole. What is the most likely cause?
A. Mitral stenosis
B. Patent ductus arteriosus
C. Aortic regurgitation
D. Tricuspid regurgitation
Correct Answer: B
Explanation:
- B is correct: Continuous murmurs occur when there is persistent flow throughout the cardiac cycle, as in patent ductus arteriosus or arteriovenous fistula 5.
- A is incorrect: Mitral stenosis produces a diastolic murmur only 5.
- C is incorrect: Aortic regurgitation produces a diastolic murmur only 5.
- D is incorrect: Tricuspid regurgitation produces a systolic murmur only 5.
Pathophysiology: Patent ductus arteriosus creates a connection between the aorta and pulmonary artery. Because aortic pressure exceeds pulmonary artery pressure throughout the cardiac cycle (both systole and diastole), blood continuously flows from aorta to pulmonary artery, creating a continuous "machinery" murmur. The murmur is loudest at the left upper sternal border and continues without interruption through S2 5.
Question 41
A patient has a midsystolic click followed by a late systolic murmur. What is the diagnosis?
A. Aortic stenosis
B. Mitral valve prolapse
C. Tricuspid regurgitation
D. Pulmonic stenosis
Correct Answer: B
Explanation:
- B is correct: Mitral valve prolapse produces a midsystolic click (as the valve prolapses) followed by a late systolic murmur (from mitral regurgitation).
- A is incorrect: Aortic stenosis produces a crescendo-decrescendo murmur without a click 5.
- C is incorrect: Tricuspid regurgitation produces a holosystolic murmur without a click 5.
- D is incorrect: Pulmonic stenosis produces a systolic ejection murmur without a click 5.
Pathophysiology: In mitral valve prolapse, redundant mitral leaflets prolapse into the left atrium during systole. The click occurs when the leaflets reach maximum prolapse and the chordae tendineae suddenly tense. If prolapse is severe, the leaflets fail to coapt properly, causing mitral regurgitation and a late systolic murmur. Maneuvers that decrease left ventricular volume (standing, Valsalva) cause earlier prolapse, moving the click and murmur earlier in systole.
Question 42
A patient has an opening snap followed by a diastolic rumble at the apex. What is the diagnosis?
A. Mitral stenosis
B. Aortic regurgitation
C. Tricuspid stenosis
D. Mitral regurgitation
Correct Answer: A
Explanation:
- A is correct: Mitral stenosis produces an opening snap (as the stenotic valve opens) followed by a diastolic rumbling murmur at the apex.
- B is incorrect: Aortic regurgitation produces a diastolic decrescendo murmur without an opening snap 5.
- C is incorrect: Tricuspid stenosis produces similar findings but at the left lower sternal border, not apex 5.
- D is incorrect: Mitral regurgitation produces a systolic murmur, not diastolic 5.
Pathophysiology: Mitral stenosis narrows the mitral valve orifice, obstructing flow from left atrium to left ventricle. The opening snap occurs when the stenotic valve suddenly opens in early diastole, creating a high-pitched sound. The diastolic rumble represents turbulent flow through the narrowed orifice throughout diastole. The interval between S2 and the opening snap reflects stenosis severity: shorter intervals indicate more severe stenosis with higher left atrial pressure.
Question 43
A patient has a diastolic decrescendo murmur at the left sternal border. What is the diagnosis?
A. Mitral stenosis
B. Aortic regurgitation
C. Pulmonic regurgitation
D. Tricuspid stenosis
Correct Answer: B
Explanation:
- B is correct: Aortic regurgitation produces a high-pitched diastolic decrescendo murmur best heard at the left sternal border with the patient leaning forward.
- A is incorrect: Mitral stenosis produces a diastolic rumble at the apex, not a decrescendo murmur 5.
- C is incorrect: Pulmonic regurgitation produces a similar murmur but is less common and associated with pulmonary hypertension 5.
- D is incorrect: Tricuspid stenosis produces a diastolic rumble at the left lower sternal border 5.
Pathophysiology: Aortic regurgitation allows backward flow from the aorta to the left ventricle during diastole. The murmur begins immediately after S2 when the aortic valve should close. As diastole progresses, the pressure gradient between aorta and left ventricle decreases (aortic pressure falls, LV pressure rises), causing the murmur to decrescendo. Severe acute aortic regurgitation can cause early closure of the mitral valve due to rapid LV pressure rise.
Question 44
A patient has wide splitting of S2 that does not vary with respiration. What is the likely diagnosis?
A. Normal finding
B. Atrial septal defect
C. Ventricular septal defect
D. Mitral regurgitation
Correct Answer: B
Explanation:
- B is correct: Fixed splitting of S2 (wide splitting that doesn't vary with respiration) is characteristic of atrial septal defect.
- A is incorrect: Normal S2 splitting varies with respiration 5.
- C is incorrect: Ventricular septal defect doesn't cause fixed splitting 5.
- D is incorrect: Mitral regurgitation doesn't affect S2 splitting 5.
Pathophysiology: S2 has two components: aortic valve closure (A2) and pulmonic valve closure (P2). Normally, P2 occurs slightly after A2, and this splitting increases with inspiration (increased venous return delays RV ejection). In atrial septal defect, left-to-right shunting causes constant RV volume overload. The RV takes longer to eject this increased volume, delaying P2. Additionally, the shunt equalizes the respiratory effects on both ventricles, eliminating normal respiratory variation, creating fixed splitting.
Question 45
A patient has paradoxical splitting of S2 (splitting that appears with expiration). What does this indicate?
A. Normal variant
B. Delayed left ventricular ejection (e.g., left bundle branch block, aortic stenosis)
C. Atrial septal defect
D. Mitral stenosis
Correct Answer: B
Explanation:
- B is correct: Paradoxical splitting occurs when A2 is delayed beyond P2, seen with conditions that delay left ventricular ejection (left bundle branch block, severe aortic stenosis).
- A is incorrect: Paradoxical splitting is always pathologic 5.
- C is incorrect: Atrial septal defect causes fixed splitting, not paradoxical 5.
- D is incorrect: Mitral stenosis doesn't cause paradoxical splitting 5.
Pathophysiology: Normally, A2 precedes P2. In left bundle branch block, delayed left ventricular activation prolongs LV ejection, delaying A2 until after P2 (reversed order). During inspiration, increased venous return further delays P2, but the effect on A2 is greater, causing the split to narrow or disappear. During expiration, the split appears or widens—opposite of normal, hence "paradoxical." This finding indicates significant left-sided conduction or outflow abnormality.
Question 46
A patient has a loud S3 gallop. What does this indicate?
A. Normal in elderly patients
B. Volume overload or ventricular dysfunction
C. Hypertension
D. Aortic stenosis
Correct Answer: B
Explanation:
- B is correct: S3 (ventricular gallop) indicates rapid ventricular filling in early diastole, suggesting volume overload or ventricular dysfunction (heart failure).
- A is incorrect: While S3 can be normal in young people, it's pathologic in adults over 40.
- C is incorrect: Hypertension typically causes S4, not S3.
- D is incorrect: Aortic stenosis typically causes S4, not S3.
Pathophysiology: S3 occurs in early diastole when rapid ventricular filling suddenly decelerates against a non-compliant or volume-overloaded ventricle. In heart failure, the dilated, poorly functioning ventricle cannot accommodate rapid filling, creating vibrations heard as S3. In volume overload (mitral regurgitation, ventricular septal defect), excessive blood volume entering the ventricle creates S3. The sound is low-pitched, best heard with the bell at the apex, creating a "Kentucky" gallop rhythm (S1-S2-S3).
Question 47
A patient has an S4 gallop. What does this indicate?
A. Normal finding
B. Decreased ventricular compliance (hypertrophy, ischemia)
C. Volume overload
D. Mitral stenosis
Correct Answer: B
Explanation:
- B is correct: S4 (atrial gallop) indicates forceful atrial contraction against a stiff, non-compliant ventricle, seen with ventricular hypertrophy, ischemia, or hypertension.
- A is incorrect: S4 is always pathologic in adults.
- C is incorrect: Volume overload causes S3, not S4.
- D is incorrect: Mitral stenosis prevents effective atrial contraction and doesn't produce S4.
Pathophysiology: S4 occurs in late diastole during atrial contraction. When the ventricle is stiff (from hypertrophy, ischemia, or fibrosis), it resists filling. The atrium contracts forcefully to overcome this resistance, creating vibrations heard as S4. The sound is low-pitched, best heard with the bell, occurring just before S1, creating a "Tennessee" gallop rhythm (S4-S1-S2). S4 cannot occur in atrial fibrillation because there's no organized atrial contraction.
Question 48
A patient has pulsus paradoxus (>10 mmHg decrease in systolic BP with inspiration). What does this suggest?
A. Normal finding
B. Cardiac tamponade or severe asthma
C. Hypertension
D. Aortic stenosis
Correct Answer: B
Explanation:
- B is correct: Pulsus paradoxus (exaggerated decrease in systolic blood pressure with inspiration) is characteristic of cardiac tamponade, constrictive pericarditis, or severe asthma.
- A is incorrect: Normal inspiratory decrease is <10 mmHg.
- C is incorrect: Hypertension doesn't cause pulsus paradoxus.
- D is incorrect: Aortic stenosis causes pulsus parvus et tardus, not paradoxus.
Pathophysiology: Normally, inspiration causes a small (<10 mmHg) decrease in systolic BP due to increased venous return to the right heart, causing the interventricular septum to bulge leftward, reducing LV filling and stroke volume. In tamponade, the rigid pericardium exaggerates this ventricular interdependence. Inspiration dramatically increases RV filling, causing marked septal shift and severely reducing LV stroke volume, producing pulsus paradoxus. This finding indicates hemodynamically significant tamponade.
Question 49
A patient has jugular venous distention with prominent "a" waves. What does this indicate?
A. Tricuspid regurgitation
B. Increased resistance to right atrial emptying (tricuspid stenosis, RV dysfunction)
C. Atrial fibrillation
D. Normal finding
Correct Answer: B
Explanation:
- B is correct: Prominent "a" waves in the jugular venous pulse indicate forceful right atrial contraction against increased resistance (tricuspid stenosis, pulmonary hypertension, RV hypertrophy).
- A is incorrect: Tricuspid regurgitation causes prominent "v" waves (systolic), not "a" waves.
- C is incorrect: Atrial fibrillation eliminates "a" waves due to absent organized atrial contraction.
- D is incorrect: Prominent "a" waves are pathologic.
Pathophysiology: The "a" wave represents atrial contraction in late diastole. When the right ventricle is stiff (hypertrophy, ischemia) or the tricuspid valve is stenotic, resistance to atrial emptying increases. The right atrium contracts more forcefully to overcome this resistance, creating prominent "a" waves visible in the jugular veins. Giant "a" waves occur with complete heart block when the atrium contracts against a closed tricuspid valve.
Question 50
A patient has jugular venous distention with prominent "v" waves. What does this indicate?
A. Tricuspid stenosis
B. Tricuspid regurgitation
C. Mitral regurgitation
D. Pulmonary stenosis
Correct Answer: B
Explanation:
- B is correct: Prominent "v" waves (systolic waves) in the jugular venous pulse indicate tricuspid regurgitation, with blood regurgitating back into the right atrium during ventricular systole.
- A is incorrect: Tricuspid stenosis causes prominent "a" waves, not "v" waves.
- C is incorrect: Mitral regurgitation doesn't affect jugular venous pulsations.
- D is incorrect: Pulmonary stenosis doesn't cause prominent "v" waves.
Pathophysiology: The "v" wave represents venous filling of the right atrium during ventricular systole (when the tricuspid valve is normally closed). In tricuspid regurgitation, the incompetent valve allows blood to flow backward from the right ventricle into the right atrium during systole. This regurgitant flow creates abnormally large "v" waves visible in the jugular veins. Severe tricuspid regurgitation can cause the entire jugular vein to pulsate with each systole (systolic pulsation).