Case Studies & Practical Application Flashcards

A 42-year-old woman with SLE presents with dyspnea and echo showing thickened mitral and aortic leaflets with regurgitation but no vegetations. Blood cultures are negative. What is the most likely diagnosis?

Answer: Libman-Sacks endocarditis

Libman-Sacks endocarditis is a nonbacterial thrombotic endocarditis associated with SLE, characterized by sterile vegetations typically on both sides of the valve leaflets.

A 68-year-old man with prior CABG presents with recurrent angina. Stress imaging reveals ischemia in the LAD territory. Angiography shows patent LIMA-LAD graft with a 90% stenosis of the proximal LAD native vessel proximal to the anastomosis. What is the preferred strategy?

Answer: PCI of the native LAD proximal lesion

PCI of the native coronary artery proximal to a patent bypass graft anastomosis is preferred over redo surgery when feasible, avoiding graft manipulation.

A 25-year-old man with Marfan syndrome is found to have an aortic root diameter of 4.7 cm on annual surveillance. He is asymptomatic. Which management is most appropriate?

Answer: Elective aortic root replacement

Guidelines recommend prophylactic aortic root replacement in Marfan syndrome when the aortic root diameter reaches ≥4.5 cm, or when growth rate exceeds 0.5 cm/year.

A 70-year-old man with known severe AS (AVA 0.65 cm²) and EF 25% presents with mean gradient of only 28 mmHg. What test best differentiates true severe AS from pseudo-severe AS in this context?

Answer: Dobutamine stress echocardiography

Dobutamine stress echocardiography distinguishes true severe AS (AVA remains low at higher flow) from pseudo-severe AS (AVA increases with dobutamine) in low-flow, low-gradient AS.

A 52-year-old woman with HCM and LVOT gradient of 75 mmHg at rest has NYHA class III symptoms despite maximally tolerated disopyramide and metoprolol. What intervention should be considered next?

Answer: Septal reduction therapy (surgical myectomy or alcohol septal ablation)

Septal reduction therapy (surgical myectomy preferred, or alcohol septal ablation) is indicated for drug-refractory obstructive HCM with severe symptoms.

A 58-year-old man with history of IV drug use presents with fever, new murmur, and multiple pulmonary emboli on CT. Echo shows a large vegetation on the tricuspid valve. Blood cultures grow MRSA. What is the best treatment strategy?

Answer: IV vancomycin for 6 weeks; surgery only if fails

Right-sided MRSA endocarditis is initially managed with 6 weeks of IV vancomycin (or daptomycin), with surgery reserved for treatment failure or very large vegetations causing persistent sepsis.

A 45-year-old man presents with palpitations and ECG showing a short PR interval, delta waves, and wide QRS. He develops rapid AF with rates >250 bpm. What is the most dangerous drug to administer?

Answer: IV adenosine or IV verapamil

AV nodal blocking agents (adenosine, verapamil, digoxin) are contraindicated in pre-excited AF as they can accelerate conduction through the accessory pathway, precipitating VF.