Aortic Stenosis MCQ for Cardiology Fellows
Question 1: Timing of Intervention in Asymptomatic Severe AS
A 68-year-old asymptomatic patient with severe aortic stenosis (AVA 0.7 cm²) has serial echocardiograms showing LVEF decline from 62% to 56% over 6 months. According to current guidelines, what is the most appropriate management?
A) Continue watchful waiting until LVEF falls below 50%
B) Recommend aortic valve replacement now
C) Repeat echocardiogram in 12 months
D) Initiate beta-blocker therapy and reassess in 6 months
Answer: B - The ESC/EACTS 2021 guidelines recommend intervention when LVEF falls to 55% in asymptomatic patients with severe AS, while ACC/AHA 2020 guidelines use a threshold of 60% over serial imaging 1. This represents a key divergence between European and American guidelines, with the ESC threshold being more conservative 1.
Question 2: Heart Valve Team Composition
Which of the following is a Class I recommendation for managing patients with severe AS being considered for intervention?
A) Referral to a high-volume center (>100 TAVR cases/year)
B) Multidisciplinary Heart Team evaluation including cardiologists, cardiac surgeons, imaging specialists, and anesthesiologists
C) Routine psychiatric evaluation for all patients
D) Mandatory geriatric assessment for patients >75 years
Answer: B - Both ESC/EACTS and ACC/AHA guidelines provide Class I/COR I, Level of Evidence C recommendations for Heart Team evaluation 1. The Heart Team must review medical condition, determine technically feasible interventions, and discuss benefits/risks while incorporating patient values and preferences 1.
Question 3: Valve Selection by Age
A 67-year-old patient with severe symptomatic AS and low surgical risk requires aortic valve replacement. According to ESC/EACTS 2021 guidelines, what is the recommended valve type?
A) Mechanical valve
B) Bioprosthetic valve
C) Either mechanical or bioprosthetic based solely on patient preference
D) Ross procedure
Answer: B - ESC/EACTS 2021 guidelines recommend bioprosthetic valves for patients ≥65 years of age 1. This differs from ACC/AHA guidelines which employ multiple age categories with greater latitude for patient factors and preferences 1. The trend shows decreasing proportions of mechanical valve replacements across all age groups 1.
Question 4: Low-Flow/Low-Gradient AS with Reduced LVEF
A 72-year-old patient presents with dyspnea, AVA 0.8 cm², mean gradient 28 mmHg, and LVEF 35%. What is the most critical next diagnostic step?
A) Cardiac catheterization
B) Low-dose dobutamine stress echocardiography
C) Cardiac MRI for fibrosis assessment
D) Exercise stress test
Answer: B - In classic low-flow/low-gradient AS with reduced LVEF, dobutamine stress echocardiography is crucial to rule out pseudo-severe AS, as reduced LVEF may result in incomplete valve opening 2. This distinguishes true severe AS from moderate AS with poor ventricular function 2.
Question 5: Coronary Revascularization Strategy
A 75-year-old high-risk patient with severe symptomatic AS and three-vessel CAD (SYNTAX score 28) is being considered for TAVR. What is the most appropriate revascularization approach?
A) Complete surgical revascularization with SAVR
B) Conservative medical management of CAD with TAVR
C) Staged PCI followed by TAVR
D) TAVR followed by staged PCI
Answer: B - Retrospective data suggest that procedural risk does not increase in patients with CAD receiving conservative medical treatment when undergoing TAVR 1. For high-risk patients with intermediate-to-high SYNTAX scores, SAVR with percutaneous revascularization may be appropriate depending on technical considerations, but TAVR with medical management is reasonable 1.
Question 6: Concomitant Severe Primary Mitral Regurgitation
A high-surgical-risk patient has severe symptomatic AS (AVA 0.6 cm²) and severe primary mitral regurgitation. The patient is not a candidate for mitral clip due to anatomy. What is the most appropriate management?
A) Medical management only
B) TAVR alone may be appropriate if AS is the dominant lesion
C) Mandatory double-valve surgery
D) Mitral valve replacement followed by staged TAVR
Answer: B - For high-risk patients with concomitant severe symptomatic AS and severe primary MR, TAVR alone was rated as "May Be Appropriate" when double-valve surgery is too high risk and mitral clip is not feasible, if the clinician believes AS is the dominant lesion 1. Primary MR will not improve with AS correction alone 1.
Question 7: HOCM with Severe AS
A 58-year-old patient has both severe HOCM (LVOT gradient 85 mmHg) and moderate-to-severe AS (AVA 0.9 cm²). What surgical approach yields the best long-term outcomes?
A) Isolated septal myectomy
B) Isolated aortic valve replacement
C) Combined myectomy and aortic valve replacement
D) Alcohol septal ablation followed by staged TAVR
Answer: C - The American Heart Association indicates that combined surgical myectomy and aortic valve replacement in patients with severe HOCM and moderate-to-severe AS yields excellent outcomes, with 1-, 2-, and 5-year survival rates of 94%, 91%, and 83% respectively, similar to age-sex-matched general population 3. The high LVOT gradient from HOCM can mask or exaggerate AS severity 3.
Question 8: Asymptomatic Severe AS Natural History
A 70-year-old truly asymptomatic patient with severe AS (AVA 0.7 cm², LVEF 60%) asks about prognosis without intervention. What survival data should guide counseling?
A) 1-year survival >95% with watchful waiting
B) 1-year survival 67%, 2-year 56%, 5-year 38% without AVR
C) Survival equivalent to age-matched controls
D) 5-year survival >80% with medical management
Answer: B - Observational data show that asymptomatic severe AS has 1-, 2-, and 5-year survival of 67%, 56%, and 38% respectively in non-operated patients, compared to 94%, 93%, and 90% with AVR 4. The adjusted hazard ratio for death with AVR was 0.17 (95% CI 0.10-0.29), indicating dramatic survival improvement 4.
Question 9: Paradoxical Low-Flow/Low-Gradient AS
A 68-year-old patient has severe concentric LVH, LVEF 62%, AVA 0.8 cm², mean gradient 32 mmHg, and stroke volume index 32 mL/m². What additional imaging is most helpful?
A) Exercise stress echocardiography
B) Multidetector CT or TEE to evaluate valve calcification and morphology
C) Cardiac MRI for strain assessment
D) Invasive hemodynamic assessment
Answer: B - In paradoxical low-flow/low-gradient AS with preserved LVEF, multidetector CT or TEE evaluation of valve morphology and calcification helps rule out pseudo-severe stenosis and diagnostic errors 2. This is a heterogeneous disease entity where impaired filling of the concentrically hypertrophied ventricle leads to reduced stroke volume despite preserved LVEF >50% 2.
Question 10: Pre-TAVR Coronary Assessment
Which statement regarding coronary evaluation before TAVR is correct?
A) Coronary angiography is optional in patients <70 years
B) Coronary angiography is indicated in all TAVR patients as CAD prevalence is 40-75%
C) CT coronary angiography is sufficient for all patients
D) Coronary assessment is only needed if angina is present
Answer: B - Coronary angiography is indicated in all patients undergoing TAVR because coronary artery disease is common, occurring in 40% to 75% of TAVR patients 1. Concurrent coronary revascularization may be needed, particularly with multivessel or left main disease, though optimal management remains complex 1.