CSC Cardiac Subspecialty 4 — Questions and Answers
Question 1: A 72-year-old with chronic AF is on warfarin (INR 2.4) and undergoes elective percutaneous coronary intervention with drug-eluting stent placement. He has no prior bleeding history. What antithrombotic regimen is recommended at discharge?
- Triple therapy with warfarin + aspirin + clopidogrel for 12 months
- Dual therapy with warfarin + P2Y12 inhibitor for 1-6 months, then warfarin monotherapy (Correct answer)
- Aspirin + clopidogrel alone for 12 months, discontinue warfarin
- Warfarin monotherapy at INR 2.5-3.5 for 12 months
Correct answer: Dual therapy with warfarin + P2Y12 inhibitor for 1-6 months, then warfarin monotherapy
Current guidelines recommend dual antithrombotic therapy (OAC + P2Y12) for most AF patients after PCI to balance thrombotic and bleeding risk.
Question 2: On echocardiography, a patient has E velocity of 120 cm/s, E/A ratio of 2.4, deceleration time of 140 ms, and E/e' of 18. What grade of diastolic dysfunction does this represent?
- Normal diastolic function
- Grade I (impaired relaxation)
- Grade II (pseudonormal)
- Grade III (restrictive filling) (Correct answer)
Correct answer: Grade III (restrictive filling)
Grade III diastolic dysfunction (restrictive filling) is characterized by E/A >2, shortened deceleration time (<160 ms), and elevated E/e' (>14), reflecting markedly elevated filling pressures.
Question 3: A patient with acute decompensated heart failure is started on intravenous dobutamine. What is the PRIMARY mechanism by which dobutamine improves cardiac output?
- Alpha-1 adrenergic receptor stimulation causing vasoconstriction
- Beta-1 adrenergic receptor stimulation increasing myocardial contractility (Correct answer)
- Phosphodiesterase-3 inhibition preventing cAMP breakdown
- Calcium sensitization of myofilaments
Correct answer: Beta-1 adrenergic receptor stimulation increasing myocardial contractility
Dobutamine primarily acts on beta-1 adrenergic receptors to increase inotropy and heart rate, thereby augmenting cardiac output.
Question 4: Which ECG pattern is pathognomonic for acute pericarditis?
- Diffuse ST elevation with reciprocal changes in aVR and PR depression (Correct answer)
- ST elevation in leads II, III, aVF with reciprocal ST depression in aVL
- New LBBB with ST elevation in V1-V4
- Diffuse T-wave inversions with QT prolongation
Correct answer: Diffuse ST elevation with reciprocal changes in aVR and PR depression
Acute pericarditis classically shows diffuse saddle-shaped ST elevation with PR depression in most leads and reciprocal PR elevation in aVR.
Question 5: A 45-year-old with familial hypercholesterolemia (LDL 210 mg/dL on maximum-dose statin + ezetimibe) has an ASCVD risk >20%. What is the most appropriate next escalation of lipid-lowering therapy?
- Add bile acid sequestrant (cholestyramine)
- Add niacin for additional LDL reduction
- Add a PCSK9 inhibitor (evolocumab or alirocumab) (Correct answer)
- Switch to rosuvastatin 40 mg and reassess in 6 months
Correct answer: Add a PCSK9 inhibitor (evolocumab or alirocumab)
PCSK9 inhibitors reduce LDL by 50-60% and are indicated for patients with ASCVD or FH who remain above target on maximally tolerated statin + ezetimibe.
Question 6: During electrophysiology study, the His-Purkinje conduction time (HV interval) is measured at 85 ms. What is the clinical significance?
- Normal finding with no further action needed
- Suggests AV nodal re-entry tachycardia
- Suggests infra-Hisian conduction disease with risk of complete heart block (Correct answer)
- Confirms Wolff-Parkinson-White syndrome
Correct answer: Suggests infra-Hisian conduction disease with risk of complete heart block
An HV interval >70 ms (normal 35-55 ms) indicates prolonged infra-Hisian conduction, which at ≥100 ms carries risk of progression to complete AV block.
Question 7: Cardiac amyloidosis is increasingly recognized as a cause of heart failure with preserved ejection fraction. Which finding on bone scintigraphy (pyrophosphate scan) is most specific for transthyretin amyloidosis (ATTR)?
- Diffuse skeletal uptake with no cardiac uptake
- Grade 2 or 3 cardiac uptake with H/CL ratio >1.5 in the absence of monoclonal protein (Correct answer)
- Grade 1 cardiac uptake with mild diffuse skeletal uptake
- Focal uptake at the cardiac apex only
Correct answer: Grade 2 or 3 cardiac uptake with H/CL ratio >1.5 in the absence of monoclonal protein
Grade 2-3 cardiac uptake on pyrophosphate scintigraphy (H/CL >1.5) without monoclonal protein has >99% specificity for ATTR amyloidosis, obviating biopsy.
CSC Cardiac Subspecialty 4
A 72-year-old with chronic AF is on warfarin (INR 2.4) and undergoes elective percutaneous coronary intervention with drug-eluting stent placement.
He has no prior bleeding history.
What antithrombotic regimen is recommended at discharge?