Feasibility of myxomatous mitral valve repair using direct leaflet and chordal radiofrequency ablation.
OBJECTIVE
Minimally invasive repair of mitral valve prolapse (MVP) causing severe mitral regurgitation (MR) should reduce MR and have chronic durability. Our ex vivo, acute in vivo, and chronic in vivo studies suggest that direct application of radiofrequency ablation (RFA) to mitral leaflets and chordae can effect these repair goals to decrease MR.


METHODS
A total of seven canines were studied to assess the effects of RFA on mitral valve structure and function. RFA was applied ex vivo (n = 1), acutely in vivo using a right lateral thoracotomy and cardiopulmonary bypass (n = 3), and chronically in vivo using percutaneous access to the heart (n = 3). RFA was applied to the mitral valve and its associated chordae. Mitral valve structure and function (in vivo preparations) were then assessed.


RESULTS
Ex vivo application of RFA resulted in qualitative reduction in mitral leaflet surface area and chordal length. Acute in vivo application of RFA to canines found to have MVP causing severe MR demonstrated a 43.7-60.7% statistically significant (P = 0.039) reduction in postablation MR. Chronic, in vivo, percutaneous application of RFA was found to be feasible and the engendered alterations durable.


CONCLUSIONS
These data suggest that myxomatous mitral valve repair using radiofrequency energy delivered via catheter is feasible.
Williams
Jeffrey L
JL
Good Samaritan Health System, Lebanon Cardiology Associates, Lebanon, Pennsylvania 17042, USA. lcaep@hotmail.com
Toyoda
Yoshiya
Y
Ota
Takeyoshi
T
Gutkin
Dmitry
D
Katz
William
W
Zenati
Marco
M
Schwartzman
David
D
D000818:Animals; D017115:Catheter Ablation / Q000379:methods*; D004195:Disease Models, Animal; D004285:Dogs; D004452:Echocardiography; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging / Q000209:etiology / Q000628:therapy*; D008945:Mitral Valve Prolapse / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D010414:Pennsylvania; D016896:Treatment Outcome