Resynchronization of mitral valve annular segments reduces functional mitral regurgitation in cardiac resynchronization therapy.
OBJECTIVE
Cardiac resynchronization therapy (CRT) reduces the severity of functional mitral regurgitation (FMR) in patients with heart failure and left bundle branch block. Our hypothesis was that the induction of a more synchronous mitral valve anulus contraction can be a mechanism of FMR reduction in CRT patients.


METHODS
An echo tissue Doppler imaging (TDI) examination was performed at baseline and 6 months after biventricular pacing system implant in 30 patients (4 females and 26 males, 74.1+/-6.1 years) with dilatative or ischemic chronic heart failure, NYHA class = or >III, ejection fraction (EF) = or <35% and QRS = or >140 ms. EF, Myocardial Performance Index (MPI), left end-diastolic and systolic volumes (LVEDV, LVESV), mitral regurgitation jet area/left atrial area (JA/LAA), effective regurgitant orifice area (EROA), mitral anulus contraction (MAC) were evaluated. Using TDI, at the 6 left ventricle (LV) basal segments the time to the peak myocardial sustained systolic velocity (Ts) and the standard deviation (SD) of TS were evaluated.


RESULTS
At 6 months follow-up NYHA class, EF, MPI were significantly improved, LV volumes were reduced. FMR degree, evaluated both as JA/LAA and EROA, was significantly reduced. This effect was associated with the 6 basal segments resynchronization and with a more effective annular contraction.


CONCLUSIONS
Our data show that CRT by resynchronizing left ventricular basal segments produces a more effective mitral valve annulus contraction and contributes to FMR improvement. Further studies need to evaluate if this could be taken into account as new therapeutic perspective of functional mitral valve regurgitation.
Macioce
R
R
Clinical Medicine and Cardiology Institute, University of Florence, Florence, Italy. robertomacioce@hotmail.com
Cappelli
F
F
Demarchi
G
G
Lilli
A
A
Ricciardi
G
G
Pieragnoli
P
P
Colella
A
A
Michelucci
A
A
Porciani
M C
MC
Padeletti
L
L
D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008944:Mitral Valve Insufficiency / Q000150:complications / Q000628:therapy*; D010138:Pacemaker, Artificial