Ventricular performance following valve replacement for chronic mitral regurgitation: importance of chordal preservation.

OBJECTIVE

To assess immediate and late changes in left ventricular performance after mitral valve replacement (MVR) for mitral regurgitation with or without preservation of chordae tendineae.

EXPERIMENTAL DESIGN

a prospective, one year follow-up, study.

SETTING

university cardiosurgical hospital.

PATIENTS

Fourteen patients with symptomatic chronic mitral regurgitation were divided into Group A (n = 7), which underwent MVR with chordal preservation, and Group B (n = 7) which underwent MVR with chordal transection.

METHODS

Transesophageal echocardiography, obtained simultaneously with radial artery and pulmonary capillary wedge pressures over a range of loading conditions, was used to estimate left ventricular elastance (Eps), calculated as the slope of peak systolic pressure/end-systolic volume relation, and preload recruitable stroke work (PRSW). Measurements were taken intraoperatively before and after cardiopulmonary bypass, 6 hours later and 10 days later. Transthoracic echocardiography follow-up data were obtained after 3 months and one year.

RESULTS

Eps significantly decreased immediately after MVR (p = 0.018), with no difference among 2 groups. Eps gradually increased to preoperative levels 10 days after surgery. PRSW also significantly decreased after MVR (p = 0.01). The decrease was significantly larger in Group B (p = 0.038). During follow-up, Group A showed a significantly better ejection fraction (p = 0.008), and a smaller end-systolic volume index (p = 0.01) and left ventricular mass index (p = 0.04), than Group B.

CONCLUSIONS

These data support the hypothesis that chordal preservation during MVR has beneficial effects on left ventricular performance.