The right side of the heart pumps deoxygenated blood from the venous return to the lungs. It houses the tricuspid valve, located between the right atrium and ventricle, and the pulmonary valve, located between the right ventricle and the pulmonary artery. In order to simulate the valve function, the Georgia Institute of Technology CFM Lab right heart simulator has been designed.
The detailed function of the pulmonary and tricuspid valves can be investigated in the right heart model outlined above. The tricuspid valve has not received as much attention for surgical intervention as the mitral valve in the left heart. However, in later years it has become apparent that paying attention to and respecting the natural condition of the tricuspid valve is important for maintaining sufficient blood flow to the lungs. An example of a pathological condition that can be simulated is tricuspid regurgitation, which is increasingly recognized as a source of morbidity. In this case, the pulmonary valve can be simulated with a prosthesis, such as a bi-leaflet mechanical heart valve. The diseased tricuspid valve valve permits backflow of blood, and can result from a variety of causes.
The tricuspid valve consists of three leaflets. One mechanism which can cause the valve to leak is enlargement of the annulus, that attaches the leaflets to the right atrium and ventricle. This is simulated with a dedicated annulus enlargement system.
To simulate physiological dilatation with a wire is fed through a spring of the anterior and posterior segments and a rigid tube for the septal section. Thus, the anterior and posterior segments dilated while the septal section length is maintained, which mimics physiological conditions (see figure above for descriptions). It is possible to dilate the annulus to 100% of the normal size with increments of 20%.
The CFM Lab is working to better understand the mechanics underlying problems with the valves in the right heart and their treatment. Our findings directly support industrial and clinical efforts to improve device design and to optimize patient-repair and replacement selections.
- Casa LD et al. Impact of pulmonary hypertension on tricuspid valve function. Ann Biomed Eng. 2013 Apr; 41(4): 709-24.
- Spinner EM et al. Correlates of tricuspid regurgitation as determined by 3D echocardiography: pulmonary arterial pressure, ventricle geometry, annular dilatation, and papillary muscle displacement. Circ Cardiovasc Imaging. 2012 Jan; 5(1): 43-50.