Efficacy of chordal cutting to relieve chronic persistent ischemic mitral regurgitation.
BACKGROUND
Mitral regurgitation (MR) conveys adverse prognosis in ischemic heart disease. Leaflet closure is restricted by tethering to displaced papillary muscles, and is, therefore, incompletely treated by annular reduction. In an acute ischemic model, we reduced such MR by cutting a limited number of critically positioned chordae to the leaflet base that most restrict closure but are not required to prevent prolapse. Whether this is effective without prolapse, recurrent MR, or left ventricular (LV) failure in chronic persistent ischemic MR, despite greater LV remodeling, remains to be established. Therefore, we studied 7 sheep with chronic inferobasal infarcts known to produce progressive MR over 2 months. In all of those sheep, after a mean of 4.1 months, the 2 central basal (intermediate) chordae were cut at the chronic ischemic MR stage. 3-Dimensional echo quantified MR, LV function, and valve geometry. Five other sheep were followed for a mean of 7.8+/-1.2 months after inferobasal infarction with chordal cutting.


RESULTS
All 7 of the sheep with chronic ischemic MR (increased from 1.4+/-0.4 to 11.1+/-0.5 mL/beat, regurgitant fraction=39.0+/-4.2%, P<0.0001) showed anterior leaflet angulation at the basal chord insertion. Although end-systolic volume had doubled, cutting the 2 central basal chordae significantly decreased the MR to baseline (P<0.0001) without prolapse or decline in EF (41.1+/-1.5% to 42.6+/-1.6%, P=not significant [NS]). The five sheep with long-term follow-up showed no prolapse or MR, and no significant post-infarct decrease in LV ejection fraction (EF; 38.9+/-2.4% to 41.4+/-1.2%, P=NS).


CONCLUSIONS
Cutting a minimum number of basal (intermediate) chordae can improve coaptation and reduce chronic persistent ischemic MR without impairing LVEF. No adverse effects were noted long-term after chordal cutting at the time of infarction.
Messas
Emmanuel
E
Faculté de Médecine Necker-Enfants Malades, INSERM EMI-0016, Ecole de Chirurgie, Assistance Publique - Hôpitaux de Paris, Service de Cardiologie 1 et de Chirurgie Cardio -Vasculaire, Hôpital Européen Georges Pompidou, Paris, France.
Pouzet
Bruno
B
Touchot
Bernard
B
Guerrero
J Luis
JL
Vlahakes
Gus J
GJ
Desnos
Michel
M
Menasché
Philippe
P
Hagège
Albert
A
Levine
Robert A
RA
D000818:Animals; D002908:Chronic Disease; D018450:Disease Progression; D015150:Echocardiography, Doppler; D019560:Echocardiography, Three-Dimensional; D005500:Follow-Up Studies; D008943:Mitral Valve / Q000601:surgery*; D008944:Mitral Valve Insufficiency / Q000175:diagnosis / Q000209:etiology / Q000601:surgery*; D009203:Myocardial Infarction / Q000150:complications; D012756:Sheep; D016277:Ventricular Function, Left