A dynamic heart system to facilitate the development of mitral valve repair techniques.
OBJECTIVE
The development of a novel surgical tool or technique for mitral valve repair can be hampered by cost, complexity, and time associated with performing animal trials. A dynamically pressurized model was developed to control pressure and flowrate profiles in intact porcine hearts in order to quantify mitral regurgitation and evaluate the quality of mitral valve repair.


METHODS
A pulse duplication system was designed to replicate physiological conditions in explanted hearts. To test the capabilities of this system in measuring varying degrees of mitral regurgitation, the output of eight porcine hearts was measured for two different pressure waveforms before and after induced mitral valve failure. Four hearts were further repaired and tested. Measurements were compared with echocardiographic images.


RESULTS
For all trials, cardiac output decreased as left ventricular pressure was increased. After induction of mitral valve insufficiencies, cardiac output decreased, with a peak regurgitant fraction of 71.8%. Echocardiography clearly showed increases in regurgitant severity from post-valve failure and with increased pressure.


CONCLUSIONS
The dynamic heart model consistently and reliably quantifies mitral regurgitation across a range of severities. Advantages include low experimental cost and time associated with each trial, while still allowing for surgical evaluations in an intact heart.
Richards
Andrew L
AL
Department of Biomedical Engineering, North Carolina State University, Raleigh, NC 27695, USA.
Cook
Richard C
RC
Bolotin
Gil
G
Buckner
Gregory D
GD
D000818:Animals; D002302:Cardiac Output; D006348:Cardiac Surgical Procedures; D004452:Echocardiography; D004867:Equipment Design; D006321:Heart / Q000503:physiopathology*; D006352:Heart Ventricles / Q000503:physiopathology; D008943:Mitral Valve / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D008944:Mitral Valve Insufficiency / Q000503:physiopathology*; D011312:Pressure; D019651:Plastic Surgery Procedures; D034421:Sus scrofa / Q000601:surgery