What are the indications and management strategies for the Bentall procedure in patients with aortic root aneurysms?

Bentall Procedure: Indications and Management

What is the Bentall Procedure?

The Bentall procedure (modified Bentall with button technique) is a composite valve-graft conduit operation that replaces the aortic root, aortic valve, and ascending aorta with reimplantation of the coronary arteries, and is the standard surgical approach for aortic root aneurysms when valve-sparing surgery is not feasible. 1

The procedure consists of a prosthetic aortic valve (typically mechanical, though bioprosthetic may be used) sewn to an aortic graft, with direct end-to-side anastomosis of each coronary ostium to the side of the composite graft using the "button technique." 1, 2

Primary Indications for Aortic Root Surgery

Marfan Syndrome Patients

• Surgery is indicated when the aortic root diameter reaches ≥50 mm 1

• Surgery should be considered at ≥45 mm with additional risk factors including: 1

  • Family history of aortic dissection
  • Rapid aortic growth ≥0.3 cm/year (confirmed by repeated measurements using the same imaging technique)
  • Severe aortic regurgitation
  • Desire for pregnancy
  • Patient preference

• An alternative threshold uses aortic cross-sectional area to height ratio: surgery is reasonable when the maximal cross-sectional area (cm²) divided by patient height (m) is ≥10 cm²/m 1

Bicuspid Aortic Valve Patients

• Surgery is indicated at ≥50 mm aortic root diameter 1, 3
• Surgery should be considered at ≥50 mm with risk factors: coarctation of the aorta, systemic hypertension, family history of dissection, or aortic diameter increase >0.3 cm/year 1

Tricuspid Aortic Valve Patients (Non-Connective Tissue Disease)

• Surgery is indicated at ≥55 mm aortic root or ascending aorta diameter 1, 3

Bentall vs. Valve-Sparing Root Replacement: Decision Algorithm

Valve-sparing aortic root replacement (VSRR) is recommended as first-line when anatomical features of the valve allow its preservation and the surgeon has specific expertise, as it avoids lifelong anticoagulation and prosthetic valve complications. 1

Choose Bentall Procedure When:

• Significant aortic valve pathology exists: moderate to severe aortic regurgitation that cannot be corrected with valve repair 1
• Acute aortic dissection involving the root 2, 4, 5
• Unfavorable valve anatomy for preservation 1
• Emergency or urgent surgery where time constraints preclude valve-sparing techniques 4, 5
• Surgeon lacks specific expertise in valve-sparing procedures 1

Choose VSRR When:

• Aortic valve cusps are structurally normal or minimally diseased 1
• Elective surgery setting 4, 5
• Experienced surgeon and center with valve-sparing expertise 1
• Patient desires to avoid lifelong anticoagulation 1

Critical Management Considerations

Anticoagulation Requirements

Lifelong vitamin K antagonists (VKAs) are mandatory for all patients receiving a Bentall procedure with a mechanical heart valve prosthesis. 1, 3 This represents a major quality-of-life consideration and carries lifelong bleeding and thromboembolism risks.

Comparative Outcomes

The evidence reveals important distinctions between procedures:

• Bentall patients experience significantly higher rates of thromboembolic events (9% vs. 1% in VSRR patients) 4
• VSRR patients have higher reoperation rates (6% vs. 2% in Bentall patients), though 8-year freedom from aortic valve replacement is 90% 4
• Long-term survival is similar between procedures (10-year survival: 90.5% Bentall vs. 96.3% VSRR), but VSRR is associated with significantly fewer thromboembolic and hemorrhagic events 5
• Hospital mortality for elective Bentall procedure is extremely low (0-1.1%) when performed by experienced surgeons 2, 6

Surgical Technique Details

The modern modified Bentall uses the "button technique" rather than the original inclusion/wrap technique, which significantly reduces the risk of pseudoaneurysm formation. 2, 6, 7 The aorta is transected completely and the aortic wall is tacked loosely over the composite graft, with direct coronary ostial reimplantation. 2

Extent of Aortic Replacement

When aortic root repair is performed, both the aortic root and ascending aorta are replaced. 1 Although some centers advocate including hemiarch replacement at the time of elective root/ascending aorta replacement, data to support this approach are lacking. 1

Post-Operative Surveillance

After Bentall procedure, surveillance imaging of the thoracic aorta by cardiac CT or cardiac MRI is recommended at least every 3 years. 1 Early CCT within 1 month, then yearly CCT follow-up for the first 2 post-operative years and every 5 years thereafter is recommended if findings are stable. 1, 3

Common Pitfalls to Avoid

• Do not delay surgery in Marfan patients beyond 50 mm diameter: the risk of aortic dissection increases substantially when diameter exceeds 5.0 cm 1
• Do not use endovascular procedures as first-line in Marfan syndrome: open surgery is strongly preferred, with endovascular procedures reserved only for emergency settings in centers with high expertise 1
• Do not forget to assess the entire aorta: Marfan patients frequently develop aneurysms in multiple aortic segments, requiring comprehensive imaging at baseline and during follow-up 1, 7
• Do not use the original inclusion/wrap Bentall technique: the modern button technique has superseded this approach due to lower pseudoaneurysm risk 2, 6, 7