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Three-dimensional dynamic morphology of the mitral valve in different forms of mitral valve prolapse - potential implications for annuloplasty ring selection.

ABSTRACT: Real-time three-dimensional transesophageal echocardiography has increased our understanding of the distinct pathomechanisms underlying functional, ischaemic or degenerative mitral regurgitation. However, potential differences in dynamic morphology between the subtypes of degenerative mitral prolapse have scarcely been investigated.In order to compare the dynamic behavior of the different phenotypes of degenerative mitral valve prolapse, real-time three-dimensional transesophageal echocardiography recordings of 77 subjects, 27 with Barlow disease (BD), 32 with Fibroelastic deficiency (FED) and 18 normal controls (NC) were analysed.Geometric annular and valvular parameters of the myxomatous patients were significantly larger compared to controls (BD vs. FED vs. NC 3D annular area: 15 ± 2.8 vs. 13.3 ± 2.4 vs. 10.6 ± 2.3cm(2), all p < 0.01). Beside similar ellipticity, BD annuli were significantly flatter compared to FED. Myxomatous annuli appeared less dynamic than normals, with decreased overall 3D area change, however only the BD group differed from NC significantly (BD vs. FED vs. NC normalized 3D area change 4.40 vs. 6.81 vs. 9.69 %; BD vs. NC p = 0.000; FED vs. NC p = not significant, BD vs. FED p = 0.025).BD and FED differ not only in terms of valve morphology, but also annular dynamics. Both pathologies are characterized by annular dilatation. However, in BD the annulus is remarkably flattened and hypodynamic, whereas in FED its saddle-shape and contractile function is relatively preserved. These features might influence the choice of repair technique and the selection of annuloplasty ring.

SUBMITTER: Apor A

PROVIDER: S-EPMC4986382 | biostudies-other | 2016 Aug

REPOSITORIES: biostudies-other

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Project description:BackgroundFour-dimensional cardiovascular magnetic resonance (CMR) flow assessment (4D flow) allows to derive volumetric quantitative parameters in mitral regurgitation (MR) using retrospective valve tracking. However, prior studies have been conducted in functional MR or in patients with congenital heart disease, thus, data regarding the usefulness of 4D flow CMR in case of a valve pathology like mitral valve prolapse (MVP) are scarce. This study aimed to evaluate the clinical utility of cine-guided valve segmentation of 4D flow CMR in assessment of MR in MVP when compared to standardized routine CMR and transthoracic echocardiography (TTE).MethodsSix healthy subjects and 54 patients (55 ± 16 years; 47 men) with MVP were studied. TTE severity grading used a multiparametric approach resulting in mild/mild-moderate (n = 12), moderate-severe (n = 12), and severe MR (n = 30). Regurgitant volume (RVol) and regurgitant fraction (RF) were also derived using standard volumetric CMR and 4D flow CMR datasets with direct measurement of regurgitant flow (4DFdirect) and indirect calculation using the formula: mitral valve forward flow - left ventricular outflow tract stroke volume (4DFindirect).ResultsThere was moderate to strong correlation between methods (r = 0.59-0.84, p < 0.001), but TTE proximal isovelocity surface area (PISA) method showed higher RVol as compared with CMR techniques (PISA vs. CMR, mean difference of 15.8 ml [95% CI 9.9-21.6]; PISA vs. 4DFindirect, 17.2 ml [8.4-25.9]; PISA vs. 4DFdirect, 27.9 ml [19.1-36.8]; p < 0.001). Only indirect CMR methods (CMR vs. 4DFindirect) showed moderate to substantial agreement (Lin's coefficient 0.92-0.97) without significant bias (mean bias 1.05 ± 26 ml [- 50 to 52], p = 0.757). Intra- and inter-observer reliability were good to excellent for all methods (ICC 0.87-0.99), but with numerically lower coefficient of variation for indirect CMR methods (2.5 to 12%).ConclusionsIn the assessment of patients with MR and MVP, cine-guided valve segmentation 4D flow CMR is feasible and comparable to standard CMR, but with lower RVol when TTE is used as reference. 4DFindirect quantification has higher intra- and inter-technique agreement than 4DFdirect quantification and might be used as an adjunctive technique for cross-checking MR quantification in MVP.

Project description:BackgroundInitial studies have suggested the familial clustering of mitral valve prolapse, but most of them were either community based among unselected individuals or applied non-specific diagnostic criteria. Therefore little is known about the familial distribution of mitral regurgitation in a referral-type population with a more severe mitral valve prolapse phenotype. The objective of this study was to evaluate the presence of familial mitral regurgitation in patients undergoing surgery for mitral valve prolapse, differentiating patients with Barlow's disease, Barlow forme fruste and fibro-elastic deficiency.MethodsA total of 385 patients (62 ± 12 years, 63% men) who underwent surgery for mitral valve prolapse were contacted to assess cardiac family history systematically. Only the documented presence of mitral regurgitation was considered to define 'familial mitral regurgitation'. In the probands, the aetiology of mitral valve prolapse was defined by surgical observations.ResultsA total of 107 (28%) probands were classified as having Barlow's disease, 85 (22%) as Barlow forme fruste and 193 (50%) patients as fibro-elastic deficiency. In total, 51 patients (13%) reported a clear family history for mitral regurgitation; these patients were significantly younger, more often diagnosed with Barlow's disease and also reported more sudden death in their family as compared with 'sporadic mitral regurgitation'. In particular, 'familial mitral regurgitation' was reported in 28 patients with Barlow's disease (26%), 15 patients (8%) with fibro-elastic deficiency and eight (9%) with Barlow forme fruste (P < 0.001).ConclusionsIn a large cohort of patients operated for mitral valve prolapse, the self-reported prevalence of familial mitral regurgitation was 26% in patients with Barlow's disease and still 8% in patients with fibro-elastic deficiency, highlighting the importance of familial anamnesis and echocardiographic screening in all mitral valve prolapse patients.

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