Endocarditis Flashcards
Which life-threatening complication can arise from infective endocarditis if not addressed aggressively?
A. Mild stable murmur
B. Septic emboli leading to stroke or severe sepsis
C. Sinus bradycardia
D. Periodic fevers only
Correct Answer: B. Septic emboli leading to stroke or severe sepsis
Rationale:
Infective endocarditis can lead to the formation of vegetations on the heart valves. If these vegetations embolize, they can cause septic emboli that lead to stroke or severe sepsis, both of which are life-threatening complications. The other options do not represent immediate, severe complications of infective endocarditis.
Which hallmark finding on physical exam is commonly associated with infective endocarditis?
A. Chronic cough
B. New or changing cardiac murmur
C. High-pitched squeak on inspiration
D. Ascites alone
Correct Answer: B. New or changing cardiac murmur
Rationale:
In infective endocarditis, the formation of vegetations on the heart valves often leads to regurgitant flow or altered valvular function, which manifests as a new or changing cardiac murmur. This finding is a key hallmark on physical examination, helping to alert clinicians to the possibility of endocarditis. The other options are not typically associated with this condition.
- Endocarditis most commonly affects which valve in native valve disease?
A. Tricuspid valve
B. Mitral valve
C. Pulmonary valve
D. Aortic valve
o
Answer: B
o Rationale: The mitral valve is most commonly involved in native valve endocarditis.
- Which complication “will kill your patient” if endocarditis is not treated properly?
A. Development of a murmur
B. Septic shock and embolic stroke
C. Mild fever
D. Fatigue
o
Answer: B
o Rationale: Endocarditis can lead to septic shock and embolic events (e.g., stroke), which are potentially fatal.
- What is “common” in the clinical presentation of endocarditis?
A. New-onset heart murmur
B. Chronic cough
C. Lower extremity claudication
D. Hypertensive crisis
o .
Answer: A
o Rationale: A new or changing heart murmur is a frequent and important finding in endocarditis
- Which diagnostic tool is key in evaluating suspected endocarditis?
A. Chest X-ray
B. Transthoracic or transesophageal echocardiography
C. CT scan of the chest
D. Abdominal ultrasound
o Answer: B
o Rationale: Echocardiography is essential for visualizing vegetations on the valves in endocarditis.
- What is the mainstay of treatment for infective endocarditis?
A. Oral antibiotics for 7 days
B. Intravenous antibiotics for 4–6 weeks
C. Immediate surgical valve replacement in all cases
D. Beta blockers
o Answer: B
o Rationale: Long-term IV antibiotic therapy is required to eradicate infection in endocarditis.
- Which valve is most commonly affected in native valve endocarditis?
A. Aortic valve
B. Mitral valve
C. Tricuspid valve
D. Pulmonary valve
o Answer: B
o Rationale: Native valve endocarditis most commonly affects the mitral valve, although aortic involvement is also common
- What is a major risk factor for developing infective endocarditis in the context of the current opioid epidemic?
A. Advanced age
B. Diabetes mellitus
C. Intravenous drug use
D. Congenital heart disease
o
Answer: C
o Rationale: Intravenous drug use significantly increases the risk of infective endocarditis and has been on the rise with the opioid epidemic.
- Which of the following is associated with a high mortality rate in endocarditis?
A. Culture-negative endocarditis
B. Prosthetic valve endocarditis
C. Subacute bacterial endocarditis
D. Endocarditis in young, healthy patients
o Answer: B
o Rationale: Prosthetic valve endocarditis carries a higher risk for complications and mortality, partly due to more virulent organisms like MRSA early after valve implantation
- The modified Duke criteria for diagnosing endocarditis require which of the following combinations for a definitive diagnosis?
A. Two major criteria
B. One major and three minor criteria
C. Five minor criteria
D. Any of the above
o Answer: D
o Rationale: Endocarditis can be diagnosed when there are two major, one major with three minor, or five minor criteria present per the modified Duke criteria.
- Which clinical finding is commonly seen in patients with infective endocarditis?
A. New or changing heart murmur
B. Hypertension
C. Bradycardia
D. Loud S1 without murmur
o Answer: A
o Rationale: A new or evolving heart murmur is a hallmark finding in endocarditis, reflecting valve involvement.
- Which clinical finding is commonly seen in patients with infective endocarditis?
A. New or changing heart murmur
B. Hypertension
C. Bradycardia
D. Loud S1 without murmur
o Answer: A
o Rationale: A new or evolving heart murmur is a hallmark finding in endocarditis, reflecting valve involvement.
- Which of the following skin findings is most characteristic of infective endocarditis?
A. Osler nodes
B. Janeway lesions
C. Splinter hemorrhages
D. All of the above
o
Answer: D
o Rationale: Osler nodes, Janeway lesions, and splinter hemorrhages are classic peripheral stigmata seen in endocarditis
- What is the primary purpose of obtaining multiple blood cultures in suspected endocarditis?
A. To detect embolic phenomena
B. To identify the causative organism
C. To assess inflammatory markers
D. To determine the duration of antibiotic therapy
o
Answer: B
o Rationale: Multiple blood cultures are critical to isolate and identify the responsible microorganism, guiding antibiotic selection.
- Which organism is most commonly implicated in endocarditis related to IV drug use?
A. Streptococcus viridans
B. Staphylococcus aureus
C. Enterococcus faecalis
D. HACEK organisms
o Answer: B
o Rationale: Staphylococcus aureus is the most common pathogen in IV drug–associated endocarditis, known for its aggressive nature.
- In prosthetic valve endocarditis, early infections (within 60 days) are most often due to which organism?
A. Streptococcus species
B. Coagulase-negative Staphylococci or MRSA
C. Enterococcus species
D. Gram-negative bacilli
o Answer: B
o Rationale: Early prosthetic valve endocarditis is frequently due to nosocomial pathogens such as coagulase-negative staphylococci or MRSA.
- Which echocardiographic finding increases the risk of embolic complications in endocarditis?
A. Vegetations >1 centimeter in size
B. Thickened valve leaflets without vegetations
C. Pericardial effusion
D. Left ventricular hypertrophy
o Answer: A
o Rationale: Vegetations that are 1 centimeter or larger are associated with a higher risk of embolism.
- Why is endocarditis associated with a higher risk for stroke?
A. Due to persistent fever
B. Because of embolization of septic vegetations
C. Due to a direct effect of antibiotics
D. From atrial fibrillation caused by valvular dysfunction
o Answer: B
o Rationale: Septic emboli from vegetations can travel to cerebral vessels, increasing the risk of stroke.
- Which of the following is considered a common complication of infective endocarditis?
A. Acute myocardial infarction from coronary embolism
B. Embolic events (stroke, splenic infarct)
C. Atrial fibrillation
D. Hypertrophic cardiomyopathy
o Answer: B
o Rationale: Embolism is a common and serious complication, affecting various organs including the brain and spleen.
- A patient with endocarditis develops signs of heart failure. What is the likely underlying mechanism?
A. Direct myocardial invasion by bacteria
B. Severe valvular insufficiency or dehiscence
C. Conduction abnormalities leading to bradycardia
D. Systemic hypertension from cytokine release
Answer: B
o Rationale: Valve destruction or dehiscence can lead to regurgitation and heart failure in endocarditis.
- Which diagnostic imaging is most useful for visualizing vegetations on heart valves?
A. Chest X-ray
B. Transthoracic echocardiogram (TTE)
C. Cardiac MRI
D. CT scan
o Answer: B
o Rationale: A transthoracic echocardiogram is a frontline imaging modality for detecting vegetations, although transesophageal echo may be needed in some cases.
- What is the first-line treatment duration for infectious endocarditis with IV antibiotics?
A. 1–2 weeks
B. 4–6 weeks
C. 8–10 weeks
D. 12 weeks
o Answer: B
o Rationale: The standard duration of IV antibiotic therapy for endocarditis is typically 4–6 weeks, depending on the organism and clinical scenario
- When treating endocarditis, why is it important to start with broad-spectrum antibiotics and then narrow therapy?
A. To minimize cost
B. To reduce the risk of nephrotoxicity
C. To cover likely pathogens while awaiting culture results
D. To shorten the hospital stay
Answer: C
o Rationale: Empiric broad-spectrum antibiotics are started to cover likely pathogens, then tailored once culture and sensitivity results are available
- Which of the following complications is an immediate life‐threatening concern (“what will kill your patient”) in endocarditis?
A. Glomerulonephritis
B. Septic shock
C. Janeway lesions
D. Osler nodes
o Answer: B
o Rationale: Septic shock is a rapidly life‐threatening complication that can occur in endocarditis and requires prompt management.
- What is one potential iatrogenic harm (“what will harm your patient”) in the management of endocarditis?
A. Under-treatment with short-duration antibiotics
B. Overuse of prophylactic anticoagulants
C. Excessive use of steroids causing immunosuppression
D. Unnecessary surgical intervention in stable patients.
o Answer: D
o Rationale: Unnecessary or premature surgical intervention in patients without clear indications can lead to increased morbidity and mortality
- In endocarditis, which of the following is a common clinical presentation?
A. Sudden chest pain with ST elevations on EKG
B. Low-grade fever with malaise and weight loss
C. Asymptomatic presentation in early disease
D. Isolated hypertension without systemic symptoms
Answer: B
o Rationale: Patients often present with low-grade fever, malaise, and weight loss, reflecting the subacute nature of many cases.
- Which of the following organisms is most associated with subacute bacterial endocarditis?
A. Staphylococcus aureus
B. Streptococcus viridans
C. Pseudomonas aeruginosa
D. Candida albicans
o Answer: B
o Rationale: Streptococcus viridans is classically linked to subacute bacterial endocarditis, especially in patients with pre-existing valve damage.
- Which clinical feature would most strongly suggest a diagnosis of prosthetic valve endocarditis?
A. Fever in an elderly patient
B. New murmur occurring within 60 days of valve implantation
C. Weight loss and fatigue over months
D. Non-specific arthralgias
o Answer: B
o Rationale: Early prosthetic valve endocarditis often presents shortly after valve implantation with fever and a new or changing murmur, frequently due to nosocomial pathogens.
- What is a common laboratory finding in patients with infective endocarditis?
A. Markedly elevated troponin levels
B. Anemia of chronic disease
C. Hypoglycemia
D. Elevated thyroid hormones
o Answer: B
o Rationale: Anemia of chronic disease is common in infective endocarditis due to the ongoing inflammatory state.
- Which of the following embolic events is most concerning in patients with endocarditis?
A. Pulmonary embolism
B. Splenic infarct
C. Cerebral embolism leading to stroke
D. Renal infarct
o Answer: C
o Rationale: Cerebral embolism is particularly concerning because it can lead to devastating neurologic deficits and is associated with increased mortality.
- What is the significance of “culture-negative” endocarditis?
A. It indicates a viral etiology
B. It complicates the diagnosis and treatment
C. It is always due to prior antibiotic use
D. It does not affect management
o
Answer: B
o Rationale: Culture-negative endocarditis can complicate diagnosis and management because the causative organism remains unidentified, often necessitating broader-spectrum or prolonged empirical treatment.
- Which of the following peripheral stigmata is caused by immune complex deposition in endocarditis?
A. Janeway lesions
B. Osler nodes
C. Splinter hemorrhages
D. Roth spots
o Answer: B
o Rationale: Osler nodes result from immune complex deposition and are tender, raised lesions on the hands or feet.
- Why is early surgical intervention sometimes indicated in endocarditis?
A. To reduce the length of antibiotic therapy
B. To remove large vegetations that pose an embolic risk or to repair severely damaged valves
C. To immediately reverse septic shock
D. To prevent glomerulonephritis
o Answer: B
o Rationale: Surgery may be necessary to remove large, mobile vegetations or repair valves when there is severe damage leading to heart failure or an uncontrolled infection.
- What is the role of transesophageal echocardiography (TEE) in endocarditis?
A. It is less sensitive than transthoracic echo
B. It helps to detect small vegetations not seen on TTE
C. It is used only after surgical intervention
D. It replaces the need for blood cultures
Answer: B
o Rationale: TEE is more sensitive than TTE and is particularly useful in detecting small vegetations, especially in patients with prosthetic valves.
- Which complication of endocarditis directly results from immune-mediated injury to the kidneys?
A. Glomerulonephritis
B. Acute tubular necrosis
C. Nephrolithiasis
D. Renal artery stenosis
o Answer: A
o Rationale: Immune complex deposition can lead to glomerulonephritis, a recognized complication of endocarditis.
- In patients with endocarditis, which clinical sign might suggest the development of heart failure?
A. New onset murmur with pulmonary edema
B. Isolated fever without murmur
C. Elevated blood pressure
D. Bradycardia
o
Answer: A
o Rationale: A new murmur accompanied by signs of pulmonary edema suggests valvular dysfunction leading to heart failure
- Which antibiotic is often used empirically in suspected MRSA endocarditis?
A. Penicillin
B. Vancomycin
C. Amoxicillin
D. Azithromycin
o Answer: B
o Rationale: Vancomycin is commonly chosen for MRSA coverage, especially in prosthetic valve or IV drug–associated endocarditis.
- What is the primary mechanism by which bacteria adhere to heart valves in endocarditis?
A. Direct invasion through the endothelium
B. Formation of biofilms and activation of tissue factor
C. Autoimmune attack on the valve tissue
D. Chemical corrosion of the valve by bacterial toxins
o Answer: B
o Rationale: Bacteria adhere to damaged valves and form biofilms, leading to monocyte activation, cytokine release, and tissue factor production that help enlarge vegetations.
- Which patient demographic is at higher risk for endocarditis due to pre-existing valve abnormalities?
A. Young athletes
B. Patients with congenital heart disease
C. Pregnant women
D. Children under 5 years old
o
Answer: B
o Rationale: Patients with congenital heart disease or pre-existing valvular abnormalities are predisposed to endocarditis due to abnormal flow patterns that favor microbial adherence.
- What laboratory test is most important to help determine the duration and choice of antibiotic therapy in endocarditis?
A. Complete blood count
B. C-reactive protein
C. Blood culture and sensitivity
D. Liver function tests
Answer: C
o Rationale: Blood cultures are essential for identifying the causative organism and determining its antibiotic sensitivities, which guide the duration and type of therapy.
- Which of the following is a potential life‐threatening complication (“what will kill your patient”) of endocarditis?
A. Petechial rash
B. Septic shock
C. Osler nodes
D. Splinter hemorrhages
o Answer: B
o Rationale: Septic shock can rapidly lead to multi-organ failure and death, making it a critical complication in endocarditis.
- A patient with endocarditis develops acute renal failure. Which complication is most likely responsible?
A. Direct bacterial invasion of the kidneys
B. Immune complex–mediated glomerulonephritis
C. Hypercalcemia from prolonged fever
D. Dehydration from poor oral intake
o Answer: B
o Rationale: Immune complex deposition in the kidneys can lead to glomerulonephritis, resulting in acute renal failure in endocarditis.
- In the setting of endocarditis, why might a patient experience embolic events?
A. Due to increased clotting from high platelet counts
B. Because vegetations can fragment and travel to distant organs
C. Because of turbulent blood flow in dilated cardiomyopathy
D. As a result of concomitant deep vein thrombosis
o Answer: B
o Rationale: Vegetations formed on the valves are friable and can break off, leading to embolic events in various organs.
- Which of the following statements best describes “culture-negative” endocarditis?
A. It is always less severe than culture-positive endocarditis
B. It may result from prior antibiotic therapy or fastidious organisms
C. It does not require antibiotic treatment
D. It only occurs in prosthetic valves
Answer: B
o Rationale: Culture-negative endocarditis can be due to previous antibiotic use or infection with fastidious organisms that are difficult to culture.
- Which of the following is a common nonpharmacologic management strategy in endocarditis?
A. Early surgical consultation for patients with large vegetations
B. Administration of high-dose diuretics
C. Routine use of beta-blockers
D. Immediate anticoagulation therapy
o Answer: A
o Rationale: For patients with large or mobile vegetations at high risk of embolization, early surgical evaluation is critical to decide on valve repair or replacement.
- How does endocarditis commonly lead to myocardial infarction?
A. Via direct bacterial invasion of the coronary arteries
B. Through embolization of vegetations into the coronary circulation
C. Due to high fever causing increased oxygen demand
D. By causing a prothrombotic state in the aorta
Answer: B
o Rationale: Embolization of septic vegetations into the coronary arteries can cause occlusion, leading to myocardial infarction.
- Which clinical sign indicates a potentially severe systemic inflammatory response in endocarditis?
A. High-grade fever with rigors
B. Isolated low-grade fever
C. Asymptomatic bradycardia
D. Localized joint pain without fever
o Answer: A
o Rationale: A high-grade fever with rigors indicates a robust systemic inflammatory response, which can be seen in acute infective endocarditis.
- What is the potential consequence of delaying appropriate antibiotic therapy in endocarditis?
A. Development of antibiotic resistance
B. Increased risk of embolic complications and heart failure
C. Overgrowth of normal flora
D. Spontaneous resolution of the infection
o Answer: B
o Rationale: Delays in appropriate therapy allow the infection to progress, increasing the risk for complications such as embolism and heart failure.
- Which physical exam finding is most common (“what is really common”) in endocarditis?
A. New or changing cardiac murmur
B. Loud S1 without murmur
C. Pericardial friction rub
D. Fixed splitting of S2
o Answer: A
o Rationale: A new or evolving murmur is a common and early sign of endocarditis due to valve involvement.
- Why is endocarditis particularly dangerous in patients with pre-existing valvular damage?
A. Their valves are more likely to harbor bacteria due to turbulent flow
B. They have stronger immune responses
C. They rarely present with fever
D. Their vegetations are always culture negative
o Answer: A
o Rationale: Pre-existing valvular damage causes turbulent blood flow, which predisposes to endothelial injury and provides a nidus for bacterial adherence and vegetation formation.
- Which of the following best explains the pathophysiologic process leading to vegetation formation in endocarditis?
A. Direct viral invasion of the valves
B. Microbial adherence with subsequent inflammatory and thrombotic processes
C. Autoimmune destruction of the valve tissue
D. Mechanical wear and tear on the valve
Answer: B
o Rationale: Bacterial adherence triggers an inflammatory response, leading to cytokine release, monocyte activation, and thrombus formation that enlarges vegetations.
- What role do cytokines play in the pathogenesis of infective endocarditis?
A. They directly lyse bacteria
B. They contribute to inflammation and the propagation of vegetations
C. They repair damaged valve tissue
D. They inhibit biofilm formation
o Answer: B
o Rationale: Cytokines released during the inflammatory response promote further tissue damage and help in the propagation of the vegetation on the valves.
- Which complication of endocarditis is directly related to embolization from vegetations?
A. Renal failure from glomerulonephritis
B. Septic shock
C. Stroke
D. Atrial fibrillation
o Answer: C
o Rationale: Embolic fragments from vegetations can travel to cerebral circulation and cause stroke, a feared complication of endocarditis.
- Which patient scenario best illustrates a “what will harm your patient” risk in the management of endocarditis?
A. Initiating broad-spectrum antibiotics promptly
B. Delaying surgical consultation for a patient with a large, mobile vegetation
C. Monitoring blood cultures
D. Using echocardiography to evaluate vegetations
o Answer: B
o Rationale: Delaying surgical intervention in a high-risk patient can result in embolic events or heart failure, thereby harming the patient.
- What is the significance of identifying a paravalvular abscess in a patient with endocarditis?
A. It suggests a less severe infection
B. It indicates an increased risk for conduction abnormalities and requires prompt intervention
C. It is usually self-limited
D. It only occurs in culture-negative endocarditis
Answer: B
o Rationale: A paravalvular abscess is a serious complication that can disrupt the conduction system and indicates a need for urgent surgical management.
- Which statement best summarizes the critical management principles for endocarditis?
A. Immediate initiation of broad-spectrum antibiotics, obtaining serial blood cultures, supportive care, and consideration of surgical intervention when indicated
B. Short-duration antibiotic therapy with outpatient follow-up
C. Exclusive reliance on echocardiographic findings to guide therapy
D. Observation only in patients without fever
o Answer: A
o Rationale: Successful management of endocarditis requires prompt antibiotic therapy guided by cultures, supportive care to manage complications, and surgical evaluation when there is severe valvular damage or high embolic risk.
microbial infection of the endocardial surface, most commonly affecting the mitral or aortic valves.
o Endocarditis involves
include IV drug use (increasing with the opioid epidemic), prosthetic valves, pre-existing valvular damage (congenital or rheumatic), diabetes, and immunosuppression.
Risk factors of endocarditis
to vegetation formation with subsequent inflammation, embolization, and local tissue destruction
o Bacterial adherence leads
Rapid systemic inflammation due to uncontrolled infection can result in multi-organ failure.
o Septic Shock
Vegetation fragments may embolize, especially to the brain (causing stroke), the spleen, or coronary arteries (resulting in myocardial infarction).
Embolic Events
Severe valve destruction or dehiscence can precipitate acute heart failure, particularly if the patient develops acute regurgitation.
Heart Failure
This complication can lead to conduction abnormalities and requires urgent surgical management.
Paravalvular Abscess:
Delaying proper antibiotic therapy or surgical intervention in high-risk patients increases morbidity and mortality
Inappropriate or Delayed Therapy
Unnecessary or premature surgical interventions in stable patients can cause additional complications.
Overly Aggressive Surgery
: Failing to use appropriate diagnostic criteria (like the modified Duke criteria) and imaging modalities (TTE/TEE) can delay treatment.
Misdiagnosis or Under-Diagnosis
Inadequate coverage or failure to narrow therapy based on blood cultures can lead to resistant infections or unnecessary toxicity.
Empiric Therapy Risks
Patients typically present with subacute symptoms such as low-grade fever, chills, fatigue, and weight loss.
Fever and Malaise
A new or evolving murmur is a hallmark sign of valve involvement.
New or Changing Heart Murmur
Classic findings include Osler nodes, Janeway lesions, splinter hemorrhages, and Roth spots.
Peripheral Stigmata
Multiple blood cultures are essential for identifying the causative organism, though culture-negative cases do occur
Positive Blood Cultures
Transthoracic or transesophageal echocardiography often reveals vegetations; size and mobility help stratify embolic risk.
Echocardiographic Vegetations
