Histopathological maladaptive changes in the explanted human mitral leaflets correlate with changes in echocardiographic leaflet morphology and the severity of ischaemic mitral regurgitation

Abstract

Aims Several changes of the mitral valve (MV) morphology have been previously documented in ischaemic mitral regurgitation (IMR) upon macro and microscopic examination. This study aimed to correlate echocardiographic MV thickening with IMR severity and to delineate the histopathological basis of valve thickening from the explanted leaflets. Methods and results Two hundred and fifty patients were included in the echo-group; of these, 48 patients (19.2%) underwent surgical mitral valve replacement (MVR), including them in the histology-group. By echocardiography, the thickness of the anterior and posterior leaflet was more extensive in moderate to severe IMR, P < 0.001. Histology-group: patients were divided into two groups based on the median thickness: those with cusp thickness <0.42 cm in Group 1, and ≥0.42 cm in Group 2. The thickness of the base and cusp was more significant in Group 2, P < 0.05 in both. Group 2 biopsies were characterized by involvement of the three leaflet segments, myxoid tissue, and fibrosis deposition. Thicker leaflets were associated with a greater degree of mitral regurgitation (MR), P < 0.0001. In the echo-group, a median leaflet thickness of 3.5 mm of the anterior and posterior MV was independently associated with moderate to severe ischaemic MR [odds ratio (OR) 2.88, P < 0.01] and (OR 10.8, P < 0.001), respectively. Conclusion In ischaemic MR, the thicker the cusps, the worse the MR. Leaflet thickening was due to the myxoid and fibrosis deposition and was detected by echocardiography. Therefore, this method can be helpful in the evaluation of valve remodelling.

Therapeutic CCR2 Blockade Prevents Inflammation and Alleviates Myxomatous Valve Disease in Marfan Syndrome

“… 27 Moreover, comparison of human mitral valve regurgitation detected by echocardiography with histopathology of explanted tissue after repair supports a correlation between valve leaflet thickening and the extent of dysfunction. 28 In MFS, MVD often precedes the development of aortic aneurysm, and the dilated aortae in MFS mice and human patients do not exhibit increased immune cells. 9 Thus, alternative therapies may be needed to treat aortic dilation characteristic of MFS.…”

A morphofunctional analysis of the regurgitant mitral valve as a guide to repair: Another point of view

“…On the contrary, in ischemic MR a short AL is very frequent. Avila‐Vanzzini et al, 10 when ischemic MR was moderate or more, found an AL length of 24mm or less in 50% and 22 mm or less in 25% of the cases.…”