Mitral valve repair for functional mitral regurgitation: is annuloplasty alone enough?

ECG-gated MDCT after aortic and mitral valve surgery

OBJECTIVE

The purpose of this article is to review the utility of ECG-gated MDCT in evaluating postsurgical findings in aortic and mitral valves. Normal and pathologic findings after aortic and mitral valve corrective surgery are shown in correlation with the findings of the traditionally used imaging modalities echocardiography and fluoroscopy to assist in accurate noninvasive anatomic and dynamic evaluation of postsurgical valvular abnormalities.

CONCLUSION

Because of its superior spatial and adequate temporal resolution, ECG-gated MDCT has emerged as a robust diagnostic tool in the evaluation and treatment of patients with postsurgical valvular abnormalities.

An ex vivo model of left ventricular dilation and functional mitral regurgitation to facilitate the development of surgical techniques

OBJECTIVE

Functional mitral regurgitation (FMR) is a common sequelae of myocardial ischemic disease. It results from annular dilation and outward rotation of the posterior papillary muscle. Different surgical techniques are under investigation for the treatment of FMR. However, an ex vivo model of FMR would be valuable to develop and compare the effect of techniques on the geometry of the left ventricle and the correction of FMR.

METHODS

FMR was induced in explanted ovine hearts (n = 12) by manual dilation of the mitral annulus or by posterior papillary muscle repositioning with a patch. Left ventricular dimensions were measured. Mitral regurgitant volume (MRV) was measured in a continuous flow system.

RESULTS

Annular dilation significantly increased MRV from 93.0 ± 110.4 to 472.2 ± 211.8 mL/min (P = 0.031), and the patch increased it from 37.8 ± 55.2 to 365 ± 189.6 mL/min (P = 0.031), with no significant differences between the 2 groups. When both techniques were applied, MRV significantly increased to 1383.5 ± 567.0 mL/min (P = 0.0005). The left ventricular sphericity index decreased from 3.25 ± 0.7 to 2.34 ± 0.6 (P = 0.0025) after application of the patch. The posterior papillary muscle was displaced after patch placement, following an outward rotation.

CONCLUSION

This ex vivo model reproduces annular dilation and outward rotation of the posterior papillary muscle, which are both present during FMR after ischemic myocardial disease. This model could be used to evaluate and compare interventions to treat FMR.

Mitral valve surgery for dilated cardiomyopathy: current status and future roles

There are a large number of patients with functional mitral regurgitation resulting from dilated cardiomyopathy. The decision between surgical correction and medical management of severe mitral regurgitation in heart failure can be difficult. The data regarding long-term benefits and mortality after surgical intervention are contradictory. Recent data suggest that mitral regurgitation can be surgically corrected in heart failure with symptomatic improvements and beneficial reverse remodeling. Contrary to prior beliefs, mitral valve repair can be performed safely with minimal postoperative mortality. Data from multi-institutional, randomized prospective trials will help to elucidate many of the questions and concerns regarding repair of severe functional mitral regurgitation.