Restrictive annuloplasty to treat functional mitral regurgitation: optimize the restriction to improve the results?
OBJECTIVE
Today, the 'gold standard' treatment of functional mitral regurgitation (MR) is the subject of much discussion. Although restrictive annuloplasty is currently considered the most reproducible technique, the means by which the degree of annular restriction is optimized remains problematic. The study was designed in order to identify whether the degree of restriction of the mitral annulus could influence early and midterm results following the treatment of functional MR using restrictive annuloplasty.


METHODS
A total of 32 consecutive patients with functional MR grade > or = 3+ was enrolled, among whom the mean anterior-posterior (AP) mitral annulus diameter was 39 +/- 3 mm. Restrictive mitral annuloplasty (combined with coronary artery bypass grafting) was performed in all patients using a Carpentier-Edwards Classic or Physio ring (size 26 or 28). The degree of AP annular restriction was calculated for each patient, and correlated with early and mid-term residual MR and left ventricular (LV) reverse remodeling (in terms of LV end-diastolic diameter (LVEDD) and LV end-diastolic volume (LVEDV) reduction). All surviving patients were examined at a one-year follow up.


RESULTS
The mean AP mitral annulus restriction achieved was 48 +/- 4%. Intraoperatively, transesophageal echocardiography showed no residual MR in any patient. Before discharge from hospital, transthoracic echocardiography confirmed an absence of residual MR and showed significant LV reverse remodeling (LVEDV from 121 +/- 25 ml to 97 +/- 26 ml; LVEDD from 55 +/- 6 mm to 47 +/- 8 mm). A significant correlation (r = 0.57, p < 0.001) was identified between the degree of AP annulus restriction and LVEDV reduction. A cut-off of annular restriction of 40% (based on AP annulus measurement) correlated with a more significant reverse remodeling. The early postoperative data, with no recurrence of significant MR, was confirmed at a one-year follow up examination.


CONCLUSIONS
A marked restriction of the AP mitral annulus diameter (> 40% of preoperative) appears to have a favorable influence on early postoperative LV reverse remodeling, and also allows for complete resolution of functional MR. In addition, 'no tolerance' of early residual MR seems to have a favorable influence on mid-term results, leading to a reduction in the one-year recurrence of significant MR.
Division of Cardiac Surgery, Civic Hospital, Brescia, Italy. ptotaro@yahoo.com
Pasquale
P
Totaro
Nicola
N
Adragna
Vincenzo
V
Argano
D000368:Aged; D001026:Coronary Artery Bypass; D017548:Echocardiography, Transesophageal; D005260:Female; D019918:Heart Valve Prosthesis Implantation / Q000379:methods*; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000209:etiology / Q000601:surgery*; D017202:Myocardial Ischemia / Q000150:complications; D016896:Treatment Outcome; D020257:Ventricular Remodeling