From the Guidelines
Valved conduits are artificial tube-like structures used in cardiac surgery that contain a valve mechanism to control blood flow, primarily used to establish connections between the heart and major blood vessels when treating complex congenital heart defects or replacing diseased heart valves and associated vessels. They are typically made of materials like Dacron or Gore-Tex with an integrated biological or mechanical valve, and common applications include reconstructing the right ventricular outflow tract in procedures like the Ross operation or repairing tetralogy of Fallot 1. The valve component ensures unidirectional blood flow, preventing backflow that could otherwise strain the heart.
Some key points to consider about valved conduits include:
- They may require replacement over time due to calcification, stenosis, or patient growth, especially in pediatric cases 1
- Predictors of conduit dysfunction and reoperation include placement of small diameter conduits; therefore, insertion of conduits with the largest possible diameter should be attempted, anticipating that subsequent valve replacement may be via a transcatheter approach 1
- Conduit intervention or replacement can result in improved hemodynamics, decreased RV size, improved RV stroke volume, and improved RV ejection fraction, as well as improved exercise capacity and peak oxygen consumption 1
- Regular monitoring through echocardiography and other cardiac imaging is necessary to assess conduit function and determine when replacement might be needed 1
In terms of management, transcatheter conduit intervention to relieve stenosis and/or regurgitation may be performed with high procedural success and low mortality rates 1. Surgical conduit replacement carries a higher risk of periprocedural complications but can result in good long-term outcomes. The choice of intervention will depend on individual patient factors and the specific characteristics of the valved conduit in question.
From the Research
Definition of Valves Conduits
- Valves conduits refer to tubes or channels that connect two parts of the heart or blood vessels, often used in cardiac surgery to repair or replace damaged heart valves [ 2 ].
- These conduits can be made of biological tissue, such as homografts, or synthetic materials, and are used to direct blood flow and maintain cardiac function [ 2 ].
Types of Valves Conduits
- Aortic conduits: used to connect the left ventricle to the aorta, often in cases of aortic stenosis or insufficiency [ 3, 4 ].
- Pulmonary conduits: used to connect the right ventricle to the pulmonary artery, often in cases of pulmonary stenosis or insufficiency [ 2 ].
- Valved conduits: used to connect the right ventricle to the pulmonary artery or left ventricle to the aorta, with a built-in valve to regulate blood flow [ 2 ].
Clinical Applications of Valves Conduits
- Transcatheter aortic valve replacement (TAVR): a minimally invasive procedure that uses a valved conduit to replace a damaged aortic valve [ 3, 4 ].
- Surgical aortic valve replacement: a traditional open-heart surgery that uses a valved conduit to replace a damaged aortic valve [ 4 ].
- Pediatric cardiac surgery: valved conduits are often used to repair or replace damaged heart valves in children [ 2 ].