Cardio 2
A 34-year-old man presents to the emergency department with an exacerbation of dilated cardiomyopathy. He denies any preceding trauma or chest pain. He does not have any family history of heart disease or sudden death. What might you see on imaging? a. Abnormally thickened left ventricle b. Infiltrative calcifications of the pericardium c. Pneumothorax due to penetrated and collapsed lung d. Spherically shaped left ventricle e. Widened mediastinum
Hide explanation The correct answer choice is a spherically shaped left ventricle (D). On x-ray of a dilated heart, there would be cardiomegaly; on echocardiography, there would be a spherically shaped left ventricle. An abnormally thickened left ventricle (A) is seen on echocardiography with hypertrophic cardiomyopathy. Without a history of preceding trauma, it is safe to say that an x- ray will not show pneumothorax due to penetrated and collapsed lung (C) or a widened mediastinum indicating aortic dissection (E). Infiltrative calcifications of the pericardium (B) are seen with constrictive pericarditis, not DCM.
You receive a myocardial biopsy slide in your pathology lab. After thorough examination of the slide, you conclude that the patient has dilated cardiomyopathy. What histological finding is most likely to be associated with this disease? a. Abnormally lengthened myocytes b. Abnormally thickened myocytes c. Disarrayed myofibrils d. High density of lysosomal inclusion bodies e. Yellow-brown granules
Hide explanation The correct answer choice is abnormally lengthened myocytes (A). Histological examination of the myocardium in DCM will reveal abnormally lengthened, less dense myocytes. In addition, the myocardium will look empty and vacuolated. Abnormally thickened myocytes (B) are seen in hypertrophic cardiomyopathy. A high density of lysosomal inclusion bodies (D) may be found in Fabry disease, a lysosomal storage disease. Disarrayed myofibrils (C) are pathognomonic for hypertrophic cardiomyopathy. Lipofuscin, the yellow-brown colored granules (E), is a normal sign of cellular aging.
A 48-year-old obese woman with dilated cardiomyopathy comes to the emergency department for worsening shortness of breath. She has had six vodka cocktails every night for the past 10 years. In addition, she finds that she frequently wakes up breathless in the middle night and must sleep with four pillows. She finds it difficult to walk more than 10 feet without stopping to catch her breath. She has never gone to the hospital before for any reason. An abdominal exam is normal. Which of the lifestyle modifications would have the greatest impact on this patient's heart disease progression? a. Alcohol abuse cessation b. Cigarette smoking cessation c. Physical exercise d. Stress reduction e. Weight loss
Hide explanation The correct answer choice is alcohol abuse cessation (A). This patient's dilated cardiomyopathy (DCM) is likely secondary to alcohol abuse. Total cessation of alcohol usage can improve and even reverse left ventricular dysfunction in DCM. Cigarette smoking cessation (B), weight loss (E), and physical exercise (C) will help ischemic cardiomyopathy. Stress (D) is associated with a takotsubo cardiomyopathy (broken-heart syndrome).
What is the most common cause of isolated right-sided heart failure? .a Cor pulmonale b. Left-sided heart failure c. Myocardial infarction d. Systemic hypertension e. Mitral regurgitation
Hide explanation The correct answer choice is cor pulmonale (A). Cor pulmonale is a phenomenon in which pulmonary hypertension causes isolated right-sided heart failure. It is the most common cause of isolated right-sided heart failure. Left-sided heart failure (B) is the most common cause of right-sided heart failure overall, but it does not result in isolated right-sided heart failure. Pulmonary hypertension, and not systemic hypertension (D), results in cor pulmonale. Myocardial infarction (C) and mitral regurgitation (E) can also result in right-sided heart failure, but they are not the most common cause.
Which of the following is characterized by impaired relaxation and impeded ability of the ventricle to fill with blood? a. Diastolic dysfunction b. Left-sided heart failure c. Right-sided heart failure d. Systolic dysfunction
Hide explanation The correct answer choice is diastolic dysfunction (A), which is characterized by impaired relaxation and impeded ventricular filling with blood. This is in contrast to systolic dysfunction (D), when the ventricle has decreased force of contraction and difficulty pumping blood. Left-sided (B) and right-sided (C) heart failure are descriptions of clinical syndromes, not mechanisms of ventricular dysfunction.
A deceased 26-year-old female patient arrives in your autopsy room. She had a history of sudden fainting spells while running. Her medical history is negative for drug use, neurological problems, and pulmonary disease. Her father passed away at a young age. Upon gross heart inspection, you would notice: a. Anomalous coronary artery anatomy b. Bicuspid aortic valve c. Dilated walls of both ventricles d. Friable vegetative masses on the mitral valve e. Increased wall thickness of the left ventricle
Hide explanation The correct answer choice is increased wall thickness of the left ventricle (E). Gross inspection of the heart will reveal thickened ventricular walls. Anomalous coronary artery anatomy (A) and bicuspid aortic valve (B) are not involved in the pathology of HCM. Dilated walls of both ventricles (C) occurs in dilated cardiomyopathy, not HCM. Friable vegetative masses on the mitral valve (D) is found on gross inspection of a heart with infective endocarditis.
Which of the following is a symptom of left-sided heart failure but not right-sided heart failure? a. Ascites b. Hepatic congestion c. Jugular venous distension d. Lower extremity edema e. Pulmonary congestion
Hide explanation The correct answer choice is pulmonary congestion (E), which results from left ventricular dysfunction and congestion of fluid in the pulmonary circulation. All the other answer choices—lower extremity edema (D), hepatic congestion (B), jugular venous distension (C), and ascites (A)—can be seen in left-sided failure, but only when the left-sided failure has progressed to involve the right ventricle. These symptoms of congestion are in the systemic circulation and therefore can be seen in both left- and right-sided failure.
What is a possible mechanism for left ventricular outflow tract obstruction in hypertrophic cardiomyopathy? a. Aortic valve calcification b. Deposition of sarcoid granulomas in the LV myocardium c. Increased LV diastolic filling pressure d. Rupture of the papillary muscles in the left ventricle e. Systolic anterior motion of the mitral valve
Hide explanation The correct answer choice is systolic anterior motion of the mitral valve (E). Systolic anterior motion (SAM) of the mitral valve can cause an obstruction of the left ventricular outflow tract (LVOT). SAM is typically seen in patients with HCM. Aortic valve calcification (A) can occur with aortic stenosis, but calcification of the aortic valve does not occur in HCM. Deposition of sarcoid granulomas in the LV myocardium (B) can cause obstruction, but it is not the mechanism of obstruction in HCM. Increased LV diastolic filling pressure (C) is not a cause of obstruction. Increased LV diastolic filling pressure produces diastolic dysfunction. Rupture of the papillary muscles in the LV (D) does not cause LVOT obstruction.
You auscultate the heart of a patient who has been diagnosed with hypertrophic cardiomyopathy. You then ask the patient to bear down (perform the Valsalva maneuver). Compared with the murmur you first heard, the murmur after the maneuver be: a. Continuous "machine-like" murmur b. Diastolic crescendo-decrescendo murmur with decreased intensity c. Diastolic crescendo-decrescendo murmur with increased intensity d. Systolic crescendo-decrescendo murmur with decreased intensity e. Systolic crescendo-decrescendo murmur with increased intensity
Hide explanation The correct answer choice is systolic crescendo-decrescendo murmur with increased intensity (E). A systolic, not diastolic (B and C), murmur occurs with HCM. It produces a systolic crescendo-decrescendo murmur. But aortic stenosis can also present with a systolic crescendo-decrescendo murmur. To differentiate the two, ask the patient to perform the Valsalva maneuver. This reduces venous return to the heart. In aortic stenosis, less blood over the stenotic area decreases murmur intensity. However, in HCM less blood causes more SAM of the mitral valve, furthering obstruction. More obstruction increases the intensity of the HCM murmur (D). A continuous machine-like murmur (A) is pathognomonic for patent ductus arteriosus.
A 52-year-old man arrives at the emergency department with shortness of breath, fatigue, and failure to thrive. He says that he is not able to walk very far without stopping to catch his breath. On cardiac examination, the point of maximal impulse is laterally displaced and auscultation reveals an S3 heart sound. On x-ray, the patient's cardiac silhouette is enlarged. What is the most likely pathophysiologic process explaining this man's symptoms? a. Decrease in ventricular compliance b. Diastolic dysfunction due to ventricular remodeling c. Failure of the atrial septa to fuse d. Failure of the neural crest cells to migrate from the neural tube e. Systolic dysfunction due to ventricular remodeling
Hide explanation The correct answer choice is systolic dysfunction due to ventricular remodeling (E). The patient presents with symptoms of heart failure, including shortness of breath and dyspnea on exertion. The physical exam includes a laterally displaced point of maximal impulse (PMI), indicative of an enlarged heart. This narrows our differential diagnosis to dilated cardiomyopathy or hypertrophic cardiomyopathy. An S3 sound is heard in systolic dysfunction, which occurs in dilated cardiomyopathy. A decrease in ventricular compliance (A) can be seen in hypertrophic cardiomyopathy as the thickened walls decrease compliance. Diastolic dysfunction due to ventricular remodeling (B) does not occur in dilated cardiomyopathy; on the contrary, systolic dysfunction occurs. Failure of the atrial septa to fuse (C) is not expected in this age group. Failure of neural crest cells to migrate from the neural tube (D) is not implicated in the pathophysiology of dilated cardiomyopathy.
A 22-year-old patient comes to your clinic because he fainted during a difficult basketball practice session. He has had no travel history, no family history of deep vein thrombosis or lung disease, and no sick contacts. He denies using alcohol, cigarettes, and other recreational drugs. His father passed away at a young age due to some unknown heart problem. What is the most likely cause of this patient's symptoms? a. Amyloid deposits in the myocardium b. β-Myosin heavy chain mutation c. Infection of the myocardium by Coxsackie B virus d. Mutation of the dystrophin gene
Hide explanation The correct answer choice is β-myosin heavy chain mutation (B). Sarcomere mutations are the most common inherited form of HCM. Information supporting a diagnosis of HCM includes symptomatology and family history. Patients with HCM may have syncopal events and sudden cardiac death with physical exertion. Amyloid deposits in the myocardium (A) result in infiltrative cardiomyopathy. This may cause ventricular thickening affecting compliance; decreased compliance in amyloidosis may cause systolic dysfunction, which can mimic HCM. However, the deposition of amyloid occurs over a significant time period; this patient is too young for amyloidosis. Infection of the myocardium by Coxsackie B virus (C) is an etiology of dilated cardiomyopathy (DCM). In DCM, the heart walls may be normal thickness or thinner. DCM is not known to present with a family history of sudden death. Mutation of the dystrophin gene (D) is present in Duchene muscular dystrophy, not HCM.
What is the intrinsic firing rate of ventricular cardiomyocytes? a. 10-30/min b. 20-40/min c. 40-60/min d. 60-100/min e. >100/min
Hide explanation The correct answer is 20-40/min (B). The ventricular myocytes have an intrinsic firing rate of 20-40/min. It typically starts functioning as the failsafe pacemaker if both the SA node (intrinsic firing rate of 60-100/min [D]) and the AV node (intrinsic firing rate of 40-60/min [C]) are not working. The rate of 10-30/min (A) is so slow it would not be good fail-safe mechanism. The rate of >100/min reflects the threshold for tachycardia (E).
What is a feature of complete heart block that is not seen with any other types of heart block? a. AV dissociation b. Dropped p-waves c. Fatigue d. Syncope e. Wide QRS complexes
Hide explanation The correct answer is AV dissociation (A). AV dissociation is unique to complete heart block because no atrial impulses are transmitted to the ventricles. Dropped p-waves (B) are seen in Mobitz type I and type II second-degree heart block. Any heart block that is severe enough to cause symptoms can result in fatigue (C) and syncope (D). Wide QRS complexes (E) are seen with any heart block that affects conduction below the bundle of His.
A 55-year-old man with a history of cardiomyopathy (heart failure with an ejection fraction of 10%) is admitted for consideration of heart transplant. He is found to be in cardiogenic shock with a low cardiac output and high SVR. He is started on milrinone and listed for transplant. What is the mechanism of action of this medication? a. α1Adrenergic stimulation b. β1Adrenergic stimulation c. β2Adrenergic stimulation d. Metabolized into NO leading to vasodilation e. PDE3 inhibition
Hide explanation The correct answer is PDE3 inhibition (E). Milrinone is an inodilator that is used for cardiogenic shock. It works by inhibiting PDE3, leading to increased cAMP and increased intracellular Ca++, which causes improved cardiac contractility. Phenylephrine, epinephrine, and norepinephrine are vasopressors that all stimulate α-1 receptors (A). Dobutamine stimulates β-1 receptors to increase heart rate and contractility (B). Epinephrine, norepinephrine, dobutamine, and dopamine all cause differing degrees of β-2 adrenergic stimulation (C). Nitroprusside is a vasodilator that works when it is metabolized to NO (D).
What is the definition of first-degree AV block? a. Dropped p-waves b. Narrow QRS complex c. PR interval of >0.2 seconds d. PR segment of >0.2 seconds e. Widened QRS complex
Hide explanation The correct answer is PR interval of >0.2 seconds (C). First-degree AV block is defined as a PR interval of >0.2 seconds. Dropped p-waves (A) appear in second-degree AV block. Narrow QRS complexes (B) mean that the cardiac conduction began at or above the bundle of His, while widened QRS complexes (E) mean that the cardiac conduction began below the bundle of His. The PR segment (D) represents the conduction delay between the atrium and the ventricles and is included in the PR interval. However, it is not used in the diagnosis of first-degree AV block.
Which type of arrhythmia presents with a delta wave? Atrial flutterBrugada syndromeJunctional rhythmParoxysmal supraventricular tachycardiaWolff-Parkinson-White syndrome
Hide explanation The correct answer is Wolff-Parkinson-White syndrome (E) because WPW is characterized by an extra electrical pathway that causes ventricular pre-excitation. This translates into a delta wave on ECG. Atrial flutter (A) is characterized by a saw-tooth pattern. Brugada syndrome (B) presents with right bundle branch block and ST segment elevation in the precordial leads. Junctional rhythm (C) is a narrow complex bradyarrhythmia that presents at 40-60/min. Paroxysmal supraventricular tachycardia (D) is characterized by intermittent SVTs with consistent ventricular response and does not have delta waves.
Which of the following is true regarding the difference between acute pericarditis and constrictive pericarditis? a. Acute pericarditis develops rapidly and generally resolves within several weeks, whereas constrictive pericarditis is chronic in nature. b. Acute pericarditis is associated with pericardial calcium deposits. c. Bacterial infection can result in acute pericarditis but not constrictive pericarditis. d. Development of cardiac tamponade is only seen in constrictive pericarditis. e. Development of pericardial effusion is only seen in acute pericarditis.
Hide explanation The correct answer is acute pericarditis develops rapidly and generally resolves within several weeks, whereas constrictive pericarditis is chronic in nature (A). Pericardial calcium deposits are associated with constrictive, not acute, pericarditis (B). Bacterial infections can result in both acute and constrictive pericarditis, not just acute pericarditis (C). Similarly, cardiac tamponade can develop in both acute and constrictive pericarditis, not just acute pericarditis (D). Pericardial effusion can develop in both acute and constrictive pericarditis, not just constrictive pericarditis (E).
A 72-year-old woman develops septicemia and goes into shock after dental surgery. Which of the following symptoms raises the greatest concern for end-organ failure? a. Anuria b. Blood pressure of 90/65 mm Hg c. Heart rate of 120.min d. Respiration rate of 26/min e. Temperature of 101°F
Hide explanation The correct answer is anuria (A). When a patient in shock ceases producing urine, it's a sign that her kidneys have suffered reduced blood perfusion and are at risk for ischemia and necrosis. By contrast, tachycardia (C) and tachypnea (D) are appropriate compensations in distributive of shock, but not signs that irreversible damage has occurred. A temperature of 101°F (E) merely reflects the inflammatory response to infection. A blood pressure of 95/65 mm Hg (B) defines shock here but in itself does not indicate there is organ hypoperfusion and necrosis.
A patient describes mild limitation of physical activity due to heart failure. He can walk half a mile but gets out of breath. Which NYHA class of heart failure is he in? a. Class I b. Class II c. Class III d. Class IV e. Class V
Hide explanation The correct answer is class II (B). Class II heart failure is defined as slight limitation of physical activity. Ordinary physical activity such as walking and going up and down stairs results in fatigue, palpitation, dyspnea, or angina pectoris (mild CHF). Class I (A) heart failure has no physical limitations while Class III (C) has marked limitation of physical activity (ie, dyspnea, fatigue, palpations, or angina at short distances of 20-100 m). Class IV (D) patients experience symptoms at rest. Class V (E) is not a NYHA class.
Which of the following drugs has not been shown to reduce mortality in CHF? a. Carvedilol b. Furosemide c. Lisinopril d. Losartan e. Spironolactone
Hide explanation The correct answer is furosemide (B). Furosemide is important in treating ADHF, but it has not been shown to improve mortality in CHF. Carvedilol (A) is a nonselective adrenergic inhibitor (inhibits both α- and β-receptors); β-blocker activity has been shown to reduce morbidity and mortality, as have ACE inhibitors (lisinopril, [C]), ARBs (losartan [D]), and spironolactone (E).
ACE inhibitors and ARBs positively affect cardiac function in CHF in all the following ways except by: a. Increasing inotropy b. Preventing cardiac remodeling c. Preventing fluid retention d. Reducing afterload e. Reducing preload
Hide explanation The correct answer is increasing inotropy (A). ACE inhibitors and ARBs are an excellent drug class for treating CHF for all the other listed reasons. Preventing fluid retention (C) helps reduce preload (E) while reducing vasoconstriction reduces afterload (D); in addition, the neurohormonal blockade helps to prevent cardiac remodeling (B).
A 60-year-old man suffers a myocardial infarction. He is initially stabilized but develops a ventricular arrhythmia hours later and loses consciousness. His blood pressure falls to 90/60 mm Hg, pulse 130/min, and respirations 20/min. His exam shows tachycardia. Lungs are clear. Which of the following parameters contributes most to this patient's hypotension? a. Arterial oxygen content b. Contractility c. Heart rate (HR) d. Preload e. Vascular radius (r)
Hide explanation The correct answer is contractility (B). This patient is in cardiogenic shock. The drop in cardiac output can be due to low contractility, preload, or high afterload. Here, after an MI, the loss of myocytes drops the contractility. In heart failure, arterial oxygen content (A) would drop if there were pulmonary edema and poor oxygen exchange, but there is no evidence of that here. Heart rate (C) is increased here as a compensation for the low MAP. A high HR increases MAP. Preload (D) is reduced in hypovolemic shock, not cardiogenic shock, where it is increased because of compensatory renal reabsorption of salt and water. Vascular radius (E) is proportional to systemic vascular resistance. SVR would be increased here as a compensation for the failing heart, not decreased as a primary cause of hypotension as would be seen in distributive shock.
Which of the following diseases is least likely to cause a restrictive cardiomyopathy? a. Coronary artery disease b. Hemochromatosis c. Sarcoidosis d. Senile cardiac amyloidosis e. Systemic scleroderma
Hide explanation The correct answer is coronary artery disease (A); coronary artery disease can cause numerous issues in the heart, including other cardiomyopathies (eg, ischemic, dilated), but coronary artery disease is not associated with restrictive cardiomyopathy. Hemochromatosis (B), sarcoidosis (C), and senile cardiac amyloidosis (D) all cause a secondary, infiltrative restrictive cardiomyopathy. Systemic scleroderma (E) causes a secondary, fibrotic restrictive cardiomyopathy.
A patient comes in with mild limitation of physical activity due to heart failure. Which of the following is the most common cause of heart failure? a. Arrhythmias b. Coronary artery disease c. Diabetes d. Hypertrophic cardiomyopathy e. Toxic cardiomyopathy
Hide explanation The correct answer is coronary artery disease (CAD) (B). CAD can lead to ischemia and myocardial infarctions that can severely damage the heart. This in turn can lead to heart failure by causing structural heart changes, such as dilation, that further compromise systolic function. CAD is the leading cause of heart failure. Although the other choices (A, C, D, and E) can cause heart failure, they are not the leading cause of heart failure.
A 65-year-old man comes to the emergency department with dizziness and a rapid pulse. He has a history of diabetes mellitus and angina pectoris for which he takes metformin and nitroglycerine as needed. On exam, his pulse is irregular at 150/min and blood pressure 130/90 mm Hg. The rest of the exam is normal. His thyroid stimulating hormone level is normal, as is his echocardiogram. An ECG shows a ventricular rate of 120-150/min and an irregularly irregular rhythm with no p-waves. Which of the following drugs would be best for this patient now? a. Aspirin and nifedipine b. Aspirin and a β-blocker c. β-Blocker alone d. Dabigatran and a β-blocker e. Dabigatran and digoxin
Hide explanation The correct answer is dabigatran and a β-blocker (D). The patient has atrial fibrillation at a ventricular rate of 120-150/min and an irregularly irregular rhythm with no p-waves. Treatment of atrial fibrillation consists of (1) ruling out secondary causes like hypothyroidism and valve disease (done here), (2) anticoagulating to prevent stroke, and (3) either slowing the heartrate to 80-110/min or converting the AF to sinus using drugs or cardioversion. Here, given the multiple risk factors (age, diabetes), anticoagulation should be done using a potent anticoagulant like warfarin or dabigatran, not aspirin. Older patients do best with rate control (slowing the heart) using β-blockers, verapamil, or diltiazem. Nifedipine (A) is not used for AF, because it tends to speed the heart, not slow it as do the non-dihydropyridine calcium channel blockers (diltiazem, verapamil). Aspirin (A, B) would not be used for anticoagulation here because of the patient's multiple risk factors for stroke (age, diabetes). A β-blocker alone would not be adequate because it would not include stroke prophylaxis. Digoxin (E) is no longer used for AF because it has multiple side effects and is more toxic than other drugs like β-blockers that equally slow the heart rate.
A 36-year-old woman presents to the emergency department with chest pain. She states that the chest pain occurred suddenly and worsens with respiration, but it improves when she sits up and leans forward. During the physical exam, a pericardial friction rub is appreciated. Her medical history is relevant for systemic lupus erythematosus. Which of the following ECG findings would you expect to find for this patient? a. Absent P waves, irregularly spaced QRS complexes b. Diffuse ST elevation, PR depression c. Low-voltage QRS complexes, electrical alternans d. U waves, flattened T waves e. Wide QRS complexes, peaked T waves
Hide explanation The correct answer is diffuse ST elevation, PR depression (B). Acute pericarditis presents with pleuritic chest pain that is improved with sitting up and leaning forward; it is associated with autoimmune disorders such as systemic lupus erythematosus. On exam, a pericardial friction rub may be heard. Absent P waves and irregularly spaced QRS complexes (A) are seen in atrial fibrillation. Low voltage QRS complexes and electrical alternans (C) are seen in cardiac tamponade. U waves and flattened T waves (D) are seen in hypokalemia. Wide QRS complexes and peaked T waves (E) are seen in hyperkalemia.
How is pericardial effusion confirmed? a. Chest x-ray b. Echocardiography c. Electrocardiography d. Presence of a friction rub e. TSH
Hide explanation The correct answer is echocardiography (B). Friction rub may be seen in pericarditis, which can involve a pericardial effusion, but this physical exam finding does not confirm an effusion (D). Electrocardiography (C) can show electrical alternans and low-voltage QRS complexes; however, these do not confirm the diagnosis. Similarly, a water bottle-shaped heart can be seen on chest x-ray (A) in pericardial effusion, but this is not used as the confirmatory test. Thyroid stimulating hormone (E) may be elevated in a patient with pericardial effusion if hypothyroidism is the underlying cause.
Which of the following is a characteristic ECG finding for large pericardial effusion? a. Beck triad b. Electrical alternans c. High-voltage QRS complexes d. No discrete P waves e. Pulsus paradoxus
Hide explanation The correct answer is electrical alternans (B). This alternate beat variation in direction, amplitude, and duration of the ECG waveform is caused by the "swinging" motion of the heart within the fluid-filled pericardial sac. Pulsus paradoxus (E) is a decrease in amplitude of systolic BP by >10 mm Hg during inspiration. The Beck triad (A) consists of hypotension, distended neck veins, and muffled heart sounds. A large pericardial effusion leads to low-voltage (not high-voltage) QRS complexes (C). Atrial fibrillation (not cardiac tamponade) leads to absent discrete P waves (D).
A 35-year-old woman who is 16 weeks pregnant is admitted with confusion and cold extremities. Her blood pressure is 85/75 mm Hg, pulse 110/min, and temperature 37.8°C. The heart, lung, and abdominal/pelvic exams are normal. Which of the following would be the most appropriate initial treatment? a. Give normal saline b. Start epinephrine c. Start milrinone d. Start nitroprusside e. Start vasopressin
Hide explanation The correct answer is give normal saline (A). This pregnant woman has shock (hypotension, confusion) with a mild fever and no immediate obvious cause of hypotension. The differential diagnosis is wide, with either hypovolemic or distributive shock most likely. Even before sending her for tests, she should be given 1-2 L of normal saline to improve her blood pressure. This should only be withheld in patients with pulmonary edema, which is not present here. If there is no response, pressor agents can then be used. Although epinephrine (B) and vasopressin (E) are useful for distributive shock, this is not proven, and both can cause pregnancy termination. She has no evidence of heart failure, so the inotrope milrinone (C) is not indicated. Neither is the vasodilator nitroprusside (D) indicated, which is also contraindicated in pregnancy.
A 35-year-old woman who is 16 weeks pregnant is admitted with confusion and cold extremities. Her blood pressure is 85/75 mm Hg, pulse 110/min, and temperature 37.8°C. The heart, lung, and abdominal/pelvic exams are normal. Which of the following would be the most appropriate initial treatment? a.a Give normal saline b. Start epinephrine c. Start milrinone d. Start nitroprusside e. Start vasopressin
Hide explanation The correct answer is give normal saline (A). This pregnant woman has shock (hypotension, confusion) with a mild fever and no immediate obvious cause of hypotension. The differential diagnosis is wide, with either hypovolemic or distributive shock most likely. Even before sending her for tests, she should be given 1-2 L of normal saline to improve her blood pressure. This should only be withheld in patients with pulmonary edema, which is not present here. If there is no response, pressor agents can then be used. Although epinephrine (B) and vasopressin (E) are useful for distributive shock, this is not proven, and both can cause pregnancy termination. She has no evidence of heart failure, so the inotrope milrinone (C) is not indicated. Neither is the vasodilator nitroprusside (D) indicated, which is also contraindicated in pregnancy.
What is the key characteristic of cardiac tamponade that distinguishes it from pericardial effusion? a. Flattened neck veins b. Displaced point of maximal impulse c. Hemodynamic instability d. Hypertension e. Increased white blood cell count
Hide explanation The correct answer is hemodynamic instability (C). As fluid continues to accumulate within the pericardial cavity, pressure in the pericardial space increases and compromises filling of the right side of the heart. This can result in decreased cardiac output. Cardiac tamponade can present with the Beck triad of distended (not flattened) neck veins (A), hypotension (not hypertension) (D), and muffled heart sounds. Neither a displaced point of maximal impulse (B) or increased white blood cell count are necessary for a diagnosis of cardiac tamponade (E).
Which of the following is not an adverse effect of hydrochlorothiazide use? a. Hypercalcemia b. Hyperglycemia c. Hyperlipidemia d. Hypernatremia e. Hyperuricemia
Hide explanation The correct answer is hypernatremia (D). Hyponatremia, not hypernatremia, is an adverse effect of hydrochlorothiazide use, actually, of all diuretics. This is due to its mechanism of action—inhibiting Na+ absorption in the distal convoluted tubules. The other options, hypercalcemia (A), hyperglycemia (B), hyperlipidemia (C), and hyperuricemia (E), are all possible effects of hydrochlorothiazide use and should be monitored in heart failure patients using the drug.
What is the most common cause of left ventricular hypertrophy (LVH)? a. Arrhythmias b. Exercise c. Hypertension d. Myocardial infarction e. Pregnancy
Hide explanation The correct answer is hypertension (C). Hypertension is the most common disease in the United States, and it is the leading cause of LVH. Although exercise (B), pregnancy (E), and remodeling after myocardial infarction (D) can all cause LVH, none are the most common cause. Arrhythmias (A) are not classically known to cause LVH without the involvement of other mechanisms.
What is a consequence of activation of the RAAS in chronic heart failure? a. Decreased afterload b. Decreased arteriole vasoconstriction d. Decreased preload d. Increased afterload e. Increased renal sodium excretion 3
Hide explanation The correct answer is increased afterload (D). RAAS activation in heart failure has two overarching effects: increased preload and increased afterload, not decreased preload (C) or decreased afterload (A). This is accomplished by increased sodium absorption, not excretion (E), and increased arteriole vasoconstriction, not decreased (B). Although these effects are initially adaptive to try and maintain cardiac output, in the long-run, they become harmful because they cause increased congestion and make the failing heart pump against more afterload.
A 52-year-old truck driver suffers a pulmonary embolism after developing a deep venous thromboembolism during a 10-hour drive. If he develops shock from the pulmonary embolism, which of the following will most likely be seen? a. Decreased afterload b. Decreased heart rate c. Decreased SVR d. Increased afterload e. Increased left ventricular preload
Hide explanation The correct answer is increased afterload (D). This patient has developed a pulmonary embolism (PE) causing obstructive shock. The large PE increases the pressure inside the pulmonary arteries, and this prevents blood from filling the left ventricle, causing a drop in left ventricular (LV) preload and cardiac output. In compensation, as in heart failure, the SVR will increase, increasing afterload and helping restore the MAP to normal. Decreased afterload (A) and decreased SVR (C) are incorrect because they are opposite to the compensations seen in obstructive shock. Heart rate would be expected to increase not decrease (B), as a compensation for the reduced cardiac output. Increased left ventricular preload (E) is wrong, because LV preload drops in obstructive shock as the LV fails to fill properly.
Which of the following findings is characteristic of systolic heart failure? a. Decreased compliance of the ventricle b. Increased end-diastolic volume c. Normal end-diastolic volume d. Preserved ejection fraction e. Restriction of the heart filling
Hide explanation The correct answer is increased end-diastolic volume (B). Systolic heart failure is due to the inability of the ventricles to pump blood out of the heart. Since blood is unable to leave the ventricle, it accumulates there, subsequently increasing end-diastolic volume. Restriction of the heart filling (E), preserved ejection fraction (D), normal end-diastolic volume (C), and decreased compliance of the ventricle (A) are all associated with diastolic heart failure.
What does the end systolic pressure-volume relationship curve on a pressure-volume loop represent? a. Afterload b. Inotropy c. Preload d. Stiffness e. Stroke volume
Hide explanation The correct answer is inotropy (B). The ESPVR is the upper boundary line of the pressure-volume loop. It represents the pressure that can be generated for a given volume in the ventricle. This is also known as the Starling relationship. In chronic heart failure, the slope of this line is decreased, because at a given volume the heart generates less force. Preload (C) is the amount of volume in the ventricle just before systole, and it is shown by the intersection of the pressure-volume loop with the EDPVR curve. Afterload (A) is a measure of the pressure the ventricle is pumping against and is measured as the point of intersection of the pressure-volume loop with the ESPVR curve. Ventricular stiffness (D) is a measure of the ventricle's ability to relax or fill with blood and is represented by the EDPVR curve. Stroke volume (E) is the amount of blood ejected from the ventricle with each contraction, is measured as EDV - ESV, and is also measured as the width of the pressure-volume loop.
An 80-year-old woman with chronic kidney disease (estimated glomerular filtration rate [eGFR] 40 mL/min/1.73 m2) and cardiomyopathy (ejection fraction 25%) is admitted with confusion, lower extremity edema, dyspnea, and cold lower extremities. Her blood pressure is 85/58 mm Hg and pulse 130/min. She has an S3 heart sound and crackles halfway up both lungs, with 2+ edema to her knees. She is given several medications to treat her shock and shows clinical improvement with improved lower extremity edema and dyspnea, decreased SVR, and improved cardiac output. However, on day 3 of treatment, she develops severe nausea and vomiting. Which of the following medications is the most likely culprit? a. Dobutamine b. Epinephrine c. Furosemide d. Milrinone e. Nitroprusside
Hide explanation The correct answer is nitroprusside (E). She has cardiogenic shock and was likely started on an inotrope like dobutamine or milrinone plus a vasodilator to reduce afterload, such as nitroglycerin or nitroprusside. Particularly in patients with renal failure, the metabolite of nitroprusside thiocyanate can build up and cause toxicity, which presents as nausea and vomiting. Dobutamine (A) and milrinone (D) are inotropes that can be used to treat cardiogenic shock but do not have the side effects of nausea or vomiting. The main side effects are increased heart rate and tachyarrhythmias. Epinephrine (B) is a potent vasopressor that also can increase cardiac contractility and is sometimes used in extreme cases of cardiogenic shock. Again, it does not have the side effects of nausea or vomiting. Furosemide (C) is a diuretic used to treat volume overload, and typical side effects include acute renal injury and hypokalemia, not vomiting.
What symptoms are typically present with first-degree AV block? a. Chest pain b. Dyspnea c. Fatigue d. No symptoms e. Syncope
Hide explanation The correct answer is no symptoms (D). First-degree AV block is typically asymptomatic and found only incidentally. All the other symptoms, chest pain (A), dyspnea (B), fatigue (C), and syncope (E), can be present with Mobitz type II second-degree AV block or third-degree AV block.
Which of the following clinical findings, if present, would be most suggestive of arrhythmia as a cause of loss of consciousness? a. Thirty minutes of confusion after the episode ends b. Episodes associated with high stress c. No warning signs before the episode d. Sensory weakness immediately before the episode e. Use of enalapril (an ACE inhibitor) for longstanding hypertension
Hide explanation The correct answer is no warning signs before the episode (C). A characteristic of cardiac syncope is its sudden onset without precipitating events. Post-event confusion suggests a seizure-related postictal state (A). Episodes arising from high stress (B) suggest a vasovagal attack. Sensory weakness before the episode suggests a TIA or seizure (D). Enalapril can cause dizziness, but it much less commonly causes loss of consciousness (E).
A 65-year-old woman presents with a 2-week history of cough, fever, and chills. She is confused and disoriented. Her blood pressure is 70/50 mm Hg, pulse 125/min, and temperature 102.5°F. Exam shows right flank tenderness, and her urinalysis shows numerous white blood cells and bacteria. The blood white blood cell count is elevated. She is admitted to the intensive care unit. Her blood pressure does not change with 1 L of normal saline. Which of the following medications would be the most appropriate best next step in management? a. Digoxin b. Dobutamine c. Milrinone d. Nitroprusside e. Norepinephrine
Hide explanation The correct answer is norepinephrine (E). Norepinephrine is a vasopressor that stimulates adrenergic α and β receptors to cause vasoconstriction; it is the first-line treatment for septic shock, a form of distributive shock where the systemic vascular resistance (SVR) is decreased. Digoxin (A), dobutamine (B), and milrinone (C) are inotropes, which work by causing increased cardiac contractility. Because the patient's problem is septic shock with low SVR and normal cardiac function, none of these agents would be appropriate. Nitroprusside (D) is a vasodilator used to treat cardiogenic shock and would worsen the blood pressure in distributive shock.
Which of the following is not associated with the development of pericardial effusion? a. Cardiothoracic surgery b. Dressler syndrome c. Hypothyroidism d. Osteoporosis e. Uremia
Hide explanation The correct answer is osteoporosis (D). Cardiothoracic surgery (A), Dressler syndrome (B), hypothyroidism (C), and uremia (E) have all been associated with increased risk for pericardial effusion.
A 63-year-old man with a history of chronic left ventricular systolic heart failure presents to the emergency department with difficulty breathing. An x-ray shows significant pulmonary edema. Vital signs show a blood pressure of 130/88 mm Hg, pulse of 95/min, respiratory rate of 24/min, temperature of 98.9°F, and O2 saturation of 87% on room air. Which of the following is the best treatment for this patient? a. Furosemide, nitrates b. Furosemide, nitrates, and carvedilol c. Oxygen supplementation, furosemide d. Oxygen supplementation, nitrates
Hide explanation The correct answer is oxygen supplementation, furosemide (C). This patient with a history of chronic heart failure has the classic signs of ADHF. Oxygen supplementation and furosemide are traditional mainstay treatments of acute treatment because they improve oxygenation. Furosemide and nitrates (A), furosemide, nitrates, and carvedilol (B), and oxygen supplementation and nitrates (E) do not contain both these options, so they are incorrect.
Which of the following is a common left-sided symptom of heart failure? a. Chest pain b. Hepatomegaly c. Jugular venous distension d. Leg swelling e. Paroxysmal nocturnal dyspnea
Hide explanation The correct answer is paroxysmal nocturnal dyspnea (E) because left-sided heart failure leads to pulmonary congestion. In response to the congestion, patients experience paroxysmal nocturnal dyspnea. Systemic symptoms like hepatomegaly (B), leg swelling (C), and jugular venous distension (D) are common right-sided symptoms of heart failure. Chest pain (A) can sometimes be a symptom of heart failure, but more rarely.
Which of the following is a possible surgical treatment for pericarditis? a. AV node ablation b. Coronary stenting c. Pacemaker placement d. Pericardiectomy e. Valve replacement 5
Hide explanation The correct answer is pericardiectomy (removal of a portion or all of the pericardium) (D). Atrioventricular node ablation (A) is a possible treatment for atrial fibrillation. Coronary stenting (B) is a possible treatment for coronary artery disease. Pacemaker placement (C) may be used as a treatment for third-degree atrioventricular block. Valve replacement (E) may be used as a treatment for severe aortic stenosis.
Which of the following rhythms is characterized by a compensatory pause? a. Atrial fibrillation b. Idioventricular rhythm c. Premature ventricular contractions d. Ventricular tachycardia e. Wolff-Parkinson-White syndrome
Hide explanation The correct answer is premature ventricular contractions (C). PVCs are characterized by wide QRS complexes with a strange morphology, t-waves that are in the opposite vector as the QRS complex, and a compensatory pause after the PVC. No compensatory pauses are seen after QRS complexes in atrial fibrillation (A), idioventricular rhythm (B), ventricular tachycardia (D), or Wolff-Parkinson-White syndrome (E).
Presence of which of the following in a patient's medical history might explain the development of newly diagnosed heart failure due to diastolic dysfunction? a. Imatinib treatment for chronic myelogenous leukemia b. Statin treatment for dyslipidemia c. Tenofovir treatment for chronic hepatitis B infection d. Radiation treatment for lung cancer e. Steroids for polyarteritis nodosa
Hide explanation The correct answer is radiation treatment for lung cancer (D). Radiation treatment can lead to fibrosis of the ventricular myocardium and restrictive cardiomyopathy. This can progress to diastolic dysfunction severe enough to cause heart failure. Statin side effects include hepatotoxicity and myopathy (B). Antiviral therapy with tenofovir for chronic hepatitis B infection may cause renal insufficiency (C). Steroid treatment for polyarteritis nodosa may cause Cushing syndrome (E). Imatinib treatment for chronic myelogenous leukemia may cause fluid retention and systolic dysfunction (A).
Which of the following is not associated with constrictive pericarditis? a. Distant heart sounds on cardiac auscultation b. Jugular venous distention c. Pericardial calcium deposits on chest x-ray d. Pericardial knock on cardiac auscultation e. Reduced pericardial thickness on echocardiogram
Hide explanation The correct answer is reduced pericardial thickness on echocardiogram (E). Due to the development of pericardial fibrotic tissue seen in constrictive pericarditis, the pericardium appears thickened. Cardiac auscultation may reveal distant heart sounds (A) or a pericardial knock (D). Compression of the heart impairs the heart's ability to move blood forward, which can manifest as jugular venous distention (B). Pericardial calcium deposits on chest x-ray are a common finding in constrictive pericarditis (C).
Which type of heart disease is characterized by reduced myocardial compliance with normal ventricular wall thickness? a. Constrictive cardiomyopathy b. Dilated cardiomyopathy c. Hypertrophic cardiomyopathy d. Restrictive cardiomyopathy e. Romano-Ward syndrome
Hide explanation The correct answer is restrictive cardiomyopathy (D). Restrictive cardiomyopathy involves a decrease in compliance or an inability of the myocardial tissue to relax during diastole. The left ventricular wall thickness is usually normal. Constrictive cardiomyopathy (A) is characterized by compression, so the heart chambers would look smaller than normal. Dilated cardiomyopathy (B) involves a reduction in contractility and systolic dysfunction. Hypertrophic cardiomyopathy (C) does involve a reduction in compliance, but the heart will be grossly hypertrophic. Romano-Ward syndrome (E) is a long-QT interval syndrome and involves the rhythmogenicity of the heart, not its myocardial function.
Which of the following ECG changes is found in Brugada syndrome? a. Bradycardia b. Delta wave c. Irregularly irregular R-R intervals d. Right bundle branch block
Hide explanation The correct answer is right bundle branch block (D). Brugada pattern is characterized by right bundle branch block and ST elevation in the precordial leads. Bradycardia (A) is typically not found in Brugada pattern. Delta waves (B) are found in WPW syndrome. Irregularly irregular R-R intervals (C) are found in atrial fibrillation.
Which of the following improves chest pain caused by acute pericarditis? a. Coughing b. Deep breathing c. Hyperventilating d. Lying supine e. Sitting up and leaning forward
Hide explanation The correct answer is sitting up and leaning forward (E). Acute pericarditis causes sharp, pleuritic chest pain, meaning that pain is exacerbated by breathing. Therefore, coughing (A), deep breathing (B), and hyperventilation (C) would likely make the chest pain worse. Lying supine would not improve the chest pain (D).
You see a patient with a history of two prior coronary bypass surgeries and multiple medications for his heart failure. He presents with difficulty ambulating due to shortness of breath, worsening dyspnea, and increasing number of pillows required to sleep at night. He is taking the maximum tolerated doses of medications, and his symptoms are still getting worse. His cardiologist is considering referring him for a left ventricular assist device (LVAD). Which ACC/AHA stage of heart failure is he in? a. Stage A b. Stage B c. Stage C d. Stage D e. Stage F
Hide explanation The correct answer is stage D (D). The patient has advanced structural heart disease that warranted several cardiac surgeries and medications. He also has severe heart failure symptoms and is now being considered for advanced therapies with an LVAD. This is stage D heart failure. The other stages (A, B, and C) do not correlate with the severity of his disease. Stage F (E) is not a stage in ACC/AHA staging of heart failure.
How are compliance, contractility, and end-diastolic volume all affected by restrictive cardiomyopathy? a. All three are decreased b. All three are increased c. Compliance is decreased, contractility is decreased, and end-diastolic volume is unchanged d. Compliance is decreased, contractility is unchanged, and end-diastolic volume is decreased e. Compliance is decreased, contractility is unchanged, and end-diastolic volume is increased
Hide explanation The correct answer is that compliance is decreased, contractility is unchanged, and end-diastolic volume is decreased (D). Restriction due to either fibrosis or infiltration reduces compliance, which prevents adequate filling of the ventricles (ie, reduced end-diastolic volume). Contractility is not affected in RCM. Therefore, choices (A), (B), (C), and (E) are all incorrect.
If a patient has established cardiac tamponade, what is the next best step in their management? a. Levothyroxine b. MRI c. Observation for 5-6 days d. Serial echocardiography e. Urgent pericardiocentesis
Hide explanation The correct answer is urgent drainage of the pericardial effusion (E). Hemodynamic instability requires immediate intervention to prevent cardiogenic shock. Levothyroxine (A) may be beneficial if the patient's pericardial effusion is due to hypothyroidism; however, this would not be the immediate next step. If cardiac tamponade has been established, additional imaging such as magnetic resonance imaging (B) is not necessary. Observation for 5-6 days (C) and serial echocardiography (D) would not be appropriate for a patient with hemodynamic compromise, although conservative measures can be taken for hemodynamically stable pericardial effusion. 4
A 52-year-old man is admitted with hypotension (blood pressure 65/45 mm Hg) and fever and found to have strep pneumonia bacteremia (bloodstream infection). After fluid resuscitation, he is admitted to the intensive care unit, started on norepinephrine, and titrated to the maximum dose. His mean arterial pressure remains low, and he is acidotic with pH of 7.21. Adding which of the following medications is the best next step in management? a. Dobutamine b. Epinephrine c. Milrinone d. Nitroprusside e. Vasopressin
Hide explanation The correct answer is vasopressin (E). This man is in profound septic shock and is not responding to therapy after maximizing one vasopressor. In theory, adding any additional vasopressor—such as epinephrine or vasopressin—might work. However, vasopressin is a vasopressor that works well in acidotic environments, making it the best choice here. Epinephrine (B) is also a potent vasopressor, but it does not work as well in acidotic environments and is usually the last-line pressor because of its potent vasoconstriction, which can cause ischemia in distal vascular beds. Dobutamine (A) and milrinone (C) are both inotropes, which also cause vasodilation and would not be appropriate in septic shock treatment. Nitroprusside (D) is a vasodilator and is used to treat cardiogenic shock with high SVR, not septic shock with low SVR as in this patient.
A 52-year-old man is admitted with hypotension (blood pressure 65/45 mm Hg) and fever and found to have strep pneumonia bacteremia (bloodstream infection). After fluid resuscitation, he is admitted to the intensive care unit, started on norepinephrine, and titrated to the maximum dose. His mean arterial pressure remains low, and he is acidotic with pH of 7.21. Adding which of the following medications is the best next step in management? a. Dobutamine b. Epinephrine c. Milrinone d. Nitroprusside e. Vasopressin 4
Hide explanation The correct answer is vasopressin (E). This man is in profound septic shock and is not responding to therapy after maximizing one vasopressor. In theory, adding any additional vasopressor—such as epinephrine or vasopressin—might work. However, vasopressin is a vasopressor that works well in acidotic environments, making it the best choice here. Epinephrine (B) is also a potent vasopressor, but it does not work as well in acidotic environments and is usually the last-line pressor because of its potent vasoconstriction, which can cause ischemia in distal vascular beds. Dobutamine (A) and milrinone (C) are both inotropes, which also cause vasodilation and would not be appropriate in septic shock treatment. Nitroprusside (D) is a vasodilator and is used to treat cardiogenic shock with high SVR, not septic shock with low SVR as in this patient.
Which of the following arrhythmias is most likely to present with pulseless loss of consciousness? a. Accelerated idioventricular rhythm b. Idioventricular rhythm c. Junctional rhythm d. Ventricular fibrillation e. Ventricular tachycardia
Hide explanation The correct answer is ventricular fibrillation (D). In this arrhythmia, the ventricles quiver (fibrillate) so they produce no effective cardiac output. There is no pulse or blood pressure, and resuscitation requires defibrillation and medications during advanced cardiac life support. Accelerated idioventricular rhythm (A) and idioventricular rhythm (B) are usually asymptomatic, although slow idioventricular rhythm with pulses of 30-40/min may lead to dizziness or syncope. Junctional rhythm (C) is usually asymptomatic. Ventricular tachycardia (E) can present as a pulseless cardiac arrest but more commonly leads to dizziness, heart failure, or chest pain.
What is the most common etiology of myocarditis? a. Autoimmune diseases b. Bacterial c. Cardiotoxins d. Systemic disease e. Viral
Hide explanation The correct answer is viral (E). Viruses are the number-one cause of myocarditis. Although autoimmune diseases (A), bacteria (B), cardiotoxins (C), and systemic disease (D) can all lead to myocarditis, the most common cause is still viral.
Which of the following correctly describes the mechanism of action of digoxin and subsequent levels of intracellular Na+ and Ca2+? a. ↓ Na+-K+-ATPase activity → ↑ [Na+] → ↑ Ca2+influx via Na+-Ca2+antiporter b. ↓ Na+-K+-ATPase activity → ↑ [Na+] → ↓ Ca2+influx via Na+-Ca2+antiporter c. ↓ Na+-K+-ATPase activity → ↓ [Na+] → ↑ Ca2+influx via Na+-Ca2+antiporter d. ↑ Na+-K+-ATPase activity → ↑ [Na+] → ↑ Ca2+influx via Na+-Ca2+antiporter e. ↑ Na+-K+-ATPase activity → ↑ [Na+] → ↓ Ca2+influx via Na+-Ca2+antiporter
Hide explanation The correct answer is ↓ Na+-K+-ATPase activity → ↑ [Na+] → ↑ Ca2+ influx via Na+-Ca2+ antiporter (A). This question requires understanding the mechanism by which digoxin increases myocardial contractility. First, digoxin inhibits the activity of Na+-K+-ATPase; it does not increase it, ruling out choices (D) and (E). Reduced Na+-K+ activity leads to increased intracellular Na+ because it is not actively being pumped out; it does not decrease intracellular Na+, ruling out choice (C). Higher intracellular Na+ leads to increased Na+-Ca2+ antiporter activity and thus higher levels of Ca2+ influx. On the other hand, lower Ca+2 (B) would lead to weaker contractility since intracellular Ca+2 is required for myocardial contraction.
