What is a Bentall prosthesis?

Bentall Prosthesis: A Comprehensive Overview

The Bentall prosthesis is a composite graft consisting of a prosthetic aortic valve (either mechanical or bioprosthetic) and an aortic graft, with reimplantation of the coronary arteries into the sides of the conduit. This surgical device is used in the Bentall procedure, which is the standard treatment for patients with combined aortic valve disease and ascending aortic pathology 1.

Components and Structure

The Bentall prosthesis includes:

• A valved conduit (composite graft-valve device)
• Either a mechanical or tissue (bioprosthetic) valve component
• A tubular vascular graft component
• Provisions for coronary artery reimplantation

Some modern versions of the prosthesis incorporate "pseudosinuses of Valsalva" to reduce tension on coronary anastomoses and create a more physiological aortic root reconstruction 2.

Clinical Applications

The Bentall procedure using this prosthesis is indicated for:

1. Aortic root aneurysms with aortic valve dysfunction
2. Ascending aortic dissection with aortic valve involvement
3. Marfan syndrome with aortic root diameter ≥5.0 cm 1
4. Bicuspid aortic valve with ascending aortic dilatation >5 cm 3
5. Combined aortic valve disease and ascending aortic pathology

Surgical Techniques

There are three main variations of the Bentall procedure using this prosthesis:

1. Classic Bentall: The original technique where coronary ostia remain in continuity with the old aorta and are anastomosed to the graft 1

2. Button Bentall: The most commonly used modern technique where coronary ostia are excised in button form before being anastomosed to the graft 1, 3

3. Cabrol Modification: Used in special circumstances, particularly when mobilization of coronary buttons is difficult 3

Valve Selection

The choice between mechanical and bioprosthetic valves depends on several factors:

• Age: Mechanical valves may offer mortality benefits in patients under 50 years 4
• Anticoagulation: Mechanical valves require lifelong vitamin K antagonist therapy 1
• Durability: Mechanical valves have greater durability but higher bleeding risk

Recent evidence suggests no significant difference in long-term survival between mechanical and bioprosthetic valves in patients over 50 years undergoing the Bentall procedure 4.

Outcomes and Prognosis

When performed by experienced surgeons in specialized centers:

• Hospital mortality is approximately 5% for elective cases 3
• 5-year survival rates range from 79-95% 5, 3
• Event-free survival at 5 years is approximately 67-85% 5, 3

Emergency procedures for acute dissection carry higher mortality rates than elective surgery 6.

Follow-up Requirements

After Bentall procedure with this prosthesis:

• Early cardiovascular CT within 1 month
• Annual echocardiography to assess valve function and gradients
• Yearly CT follow-up for the first 2 post-operative years
• Follow-up every 5 years thereafter if findings are stable 1

Potential Complications

• Bleeding (particularly with mechanical valves)
• Thromboembolic events
• Endocarditis
• Paravalvular leak
• Late distal aortic segment issues requiring additional surgery

The Bentall prosthesis remains the gold standard for aortic root replacement despite the development of newer valve-sparing techniques like the David procedure (valve-sparing root replacement) 1, 5.