What is the best management approach for a patient with severe aortic stenosis (AS) and a past history of coronary artery bypass grafting (CABG)?

Management of Severe Aortic Stenosis with Prior CABG

For a patient with severe aortic stenosis and prior CABG, aortic valve replacement (either TAVR or SAVR) is indicated if the patient is symptomatic or has left ventricular systolic dysfunction (LVEF <50%), with the choice between TAVR versus SAVR determined by surgical risk assessment, anatomic suitability, and multidisciplinary Heart Team evaluation. 1, 2

Symptomatic Patients

• Intervention is Class I indication for any symptoms related to severe AS (exertional dyspnea, heart failure, angina, syncope, or presyncope), regardless of prior cardiac surgery 1
• Prior CABG increases surgical complexity but does not contraindicate either TAVR or SAVR 1, 3
• Patients with severe AS who have previously undergone AVR have significantly reduced perioperative risk for major adverse cardiovascular events (5.4% vs 20.5% in untreated AS, P<0.001) 1

Asymptomatic Patients

Intervention should be considered if: 1, 2

• LVEF <50% not attributable to other causes (Class I indication) 1
• Abnormal exercise test showing symptoms clearly related to AS (Class I indication) 1, 2
• Very severe AS (peak velocity ≥5 m/s or mean gradient ≥60 mmHg) with low surgical risk 1
• Severe valve calcification with rapid progression (velocity increase ≥0.3 m/s per year) 1, 2

TAVR versus SAVR Decision Algorithm

TAVR is preferred when: 1, 2

• Age >80 years or life expectancy <10 years for younger patients 1
• High or prohibitive surgical risk (STS-PROM ≥8%) 1
• Hostile chest anatomy from prior CABG (porcelain aorta, mediastinal scarring) 1
• Significant frailty or comorbidities (oxygen-dependent lung disease, cirrhosis, dialysis) 1
• Anatomically suitable for transfemoral access 1, 2

SAVR is preferred when: 1

• Age <65 years with low surgical risk (STS-PROM <3%) 1
• Anatomic contraindications to TAVR (excessive annular calcification, annulus size out of range) 1
• Need for concomitant coronary revascularization with complex CAD (high SYNTAX score) 1
• Small annulus requiring prosthesis <21 mm (to avoid high residual gradients with valve-in-valve TAVR) 1

Critical Evaluation Steps

Mandatory assessments before intervention: 1, 2

• Comprehensive echocardiography within 1 year to confirm AS severity (AVA ≤1.0 cm², mean gradient ≥40 mmHg, peak velocity ≥4 m/s), quantify LV function, and identify other valvular lesions 1
• Coronary angiography to assess patency of prior grafts and native coronary disease 1, 4
• Cardiac CT to evaluate aortic root anatomy, annular dimensions, valve calcification, and vascular access for TAVR 1
• Multidisciplinary Heart Team evaluation involving interventional cardiology, cardiac surgery, imaging specialists, and heart failure specialists 1, 2

Special Considerations for Prior CABG Patients

• Assess graft patency: Patent grafts may influence decision toward TAVR to avoid repeat sternotomy and graft injury risk 4
• Evaluate for additional coronary disease: If new significant CAD requiring revascularization exists, combined SAVR + redo CABG is appropriate if surgical risk is acceptable 1, 4
• Consider staged approach: For complex anatomy (e.g., concomitant abdominal aortic aneurysm), staged transcatheter procedures may minimize risk 3
• Hostile chest anatomy: Prior sternotomy with patent grafts crossing midline strongly favors TAVR over redo SAVR 1

Common Pitfalls to Avoid

• Do not delay intervention in symptomatic patients due to prior cardiac surgery—untreated symptomatic severe AS has 30-day mortality of 4.3% with noncardiac surgery 1
• Do not assume moderate AS is benign in patients with prior CABG—untreated moderate AS (AVA 1-1.5 cm²) independently predicts 2-fold higher late mortality (HR 2.01, P<0.001) 5
• Do not rely solely on STS-PROM score—factors like porcelain aorta, hostile chest, and frailty increase surgical risk beyond calculated scores and favor TAVR 1
• Do not proceed without Heart Team evaluation—the complexity of prior CABG anatomy requires multidisciplinary assessment of all treatment options 1, 2

Medical Management Considerations

• Medical therapy alone is appropriate only when: 1
  • Life expectancy <1 year due to comorbidities 1
  • Moderate to severe dementia 1
  • Medical futility (STS-PROM >15% with poor rehabilitation potential) 1
• Balloon aortic valvuloplasty may be considered as bridge to definitive intervention in critically ill patients requiring urgent noncardiac surgery 1
• No specific medical therapy (including statins) effectively treats or slows progression of severe AS 1, 6