Postoperative assessment of chordal preservation and changes in cardiac geometry following mitral valve replacement.

Mitral valve replacement (MVR) is still associated with a relatively high mortality. To investigate the influence of chordal preservation in MVR on left ventricular size and function, we studied a series of 82 patients who underwent MVR either with (group A n = 50) or without (group B n = 32) preservation of the subvalvular structures and compared the two groups. Echocardiography was performed preoperatively, and 7 days and 3 months postoperatively. Echocardiographic investigations included left atrial and ventricular diameters, right ventricular diameters and left ventricular length. Preoperatively there were no difference between the two groups of patients. Intraoperative and postoperative management was similar in the groups. Three months postoperatively echocardiographic examinations demonstrated that chordal preservation in MVR resulted in smaller left ventricular systolic and diastolic diameters (LVESD: gr. A 43.4 +/- 7.8 mm vs gr. B 48.8 +/- 9.2 mm P < 0.05, LVEDD: 57.3 +/- 7.8 mm vs 62.9 +/- 10.5 mm P < 0.05) and a significantly decreased left ventricular length (87.1 +/- 4.2 mm in gr. A vs 97.5 +/- 5.7 mm in gr. B P < 0.05). In addition, left ventricular ejection fraction in group A was significantly improved compared to group B (54.2 +/- 11.2% vs 48.1 +/- 12.4%, P < 0.05). We conclude that chordal preservation in MVR improves left ventricular function and reduces left ventricular diameters and volumes compared to resection of the mitral subvalvular appartus and that these beneficial effects can be maintained in the postoperative course.