Repercussion of functional mitral regurgitation on reverse remodelling in cardiac resynchronization therapy.
OBJECTIVE
Cardiac resynchronization therapy (CRT) reduces the degree of functional mitral regurgitation (FMR). However, FMR has also been associated with a lack of clinical response to CRT. We undertook this study to determine whether the presence of FMR influences the reverse remodelling induced by CRT.


RESULTS
We used Doppler echocardiography to assess 20 patients with dilated cardiomyopathy before and 6 months after undergoing CRT. We evaluated the effect of reverse remodelling (reduction > or = 10% in end-systolic volume) according to the presence or absence of important FMR, defined as a regurgitant orifice area (ROA) of > or = 0.20 cm(2). Of the 20 patients (mean age, 64.7 +/- 8.2 years, eight women), 9 had marked FMR (ROA 0.40 +/- 0.12 cm(2)), 6 mild FMR (ROA 0.15 +/- 0.02 cm(2)), and 5 had trivial or no FMR. CRT reduced the presence of mitral regurgitation by 33.3% and induced reverse remodelling in 60% of the patients. A ROA > or = 0.20 cm(2) was associated with a lack of reverse remodelling, despite presenting similar baseline characteristics and a reduction in asynchrony to the other patients. Reverse remodelling was produced in all the other patients, with a significant reduction in end-systolic volume (41.7 +/- 21%; P = 0.003), accompanied by improvement in the ejection fraction (P = 0.003) and myocardial performance index (P = 0.027).


CONCLUSIONS
CRT improved FMR, although the baseline presence of important mitral regurgitation, with a ROA > or = 0.20 cm(2), in patients undergoing CRT was associated with a lack of response in reverse remodelling.
Cabrera-Bueno
Fernando
F
Servicio de Cardiología, Hospital Universitario Virgen de la Victoria de Málaga, Campus de Teatinos s/n, Colonia Santa Ines, Malaga, Spain. fjcabrera@secardiologia.es
García-Pinilla
José Manuel
JM
Peña-Hernández
José
J
Jiménez-Navarro
Manuel
M
Gómez-Doblas
Juan José
JJ
Barrera-Cordero
Alberto
A
Alzueta-Rodríguez
Javier
J
de Teresa-Galván
Eduardo
E
D000368:Aged; D002304:Cardiac Pacing, Artificial; D009202:Cardiomyopathies / Q000503:physiopathology* / Q000628:therapy*; D004452:Echocardiography / Q000379:methods; D015150:Echocardiography, Doppler; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000503:physiopathology* / Q000628:therapy*; D006352:Heart Ventricles / Q000503:physiopathology / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000503:physiopathology* / Q000628:therapy*; D009200:Myocardial Contraction; D017202:Myocardial Ischemia / Q000503:physiopathology / Q000628:therapy; D010138:Pacemaker, Artificial; D011237:Predictive Value of Tests; D016896:Treatment Outcome; D016277:Ventricular Function, Left; D020257:Ventricular Remodeling