Congenital malformations of the mitral valve

Abstract

Congenital malformations of the mitral valve may be encountered in isolation or in association with other congenital heart defects. Each level of the mitral valve complex may be affected, according to the embryological development, explaining the fact that these lesions are sometimes associated with each other. As a perfect preoperative assessment is of importance, good knowledge of both normal and abnormal anatomy is required in order to guide the surgeon accurately. This review presents the different embryological, anatomical and echocardiographic aspects of the congenital mitral anomalies.

Effect of altered haemodynamics on the developing mitral valve in chick embryonic heart

“…These valves ensure unidirectional blood flow to both pulmonary and systemic systems. Aberrant developmental mechanisms can occur and give rise to congenital valve defects [1]. Congenital valve malformations have a prevalence of 2% of live births and occur in a number of genetic syndromes such as Marfan syndrome and trisomy 21, and can happen in isolation or in conjunction with other heart defects including hypoplastic left heart syndrome and Tetralogy of Fallot [1], [2], [3].…”

Congenital isolated cleft mitral valve leaflet and apical muscular ventricular septal defect in a Holstein calf

“…11 This type of cleft MV leaflet is commonly associated with AVSDs, whereas a true 'isolated' cleft MV occurs without an AVSD, and in humans, the cleft is usually directed toward the aortic root, as was the case in the calf described in the current report. 4,12 In humans, 50% of cases of cleft MV have severe MR. 2 Similarly, the calf in the current report was considered to have at least moderate MR based on subjective assessment, which likely contributed to left-sided volume overload and pulmonary hypertension. Chordal attachments to the ventricular septum have been reported to cause subaortic stenosis in people and a dog.…”

“…7 The exact embryologic origin of MV cleft is unknown, however an isolated cleft is thought to be due to incomplete fusion of these superior and inferior cushions. 2 Chordae tendineae develop from the same cushion tissue as the leaflets and abnormal attachment of the papillary muscle insertion can potentially lead to abnormal, thickened, or shortened chordae. 2,4,8 Historically, a cleft MV has been linked developmentally with atrioventricular septal defects (AVSDs).…”

“…2 Chordae tendineae develop from the same cushion tissue as the leaflets and abnormal attachment of the papillary muscle insertion can potentially lead to abnormal, thickened, or shortened chordae. 2,4,8 Historically, a cleft MV has been linked developmentally with atrioventricular septal defects (AVSDs). 3 An isolated cleft MV is however, morphologically distinct from a cleft in the MV portion of an AVSD.…”

Three-dimensional echocardiography in unicuspid mitral valve

“…This report demonstrates that real-time three-dimensional (3D) echocardiography can be an optimal tool to evaluate congenital malformation of the mitral valve. Real-time 3D echocardiography is important in diagnosing heart valve diseases because it enhances the evaluation of morphologic abnormalities and improves understanding of complex relationships through more precise imaging and presentation of interrelations of different parts of the mitral apparatus [1][2][3] . The downside of real-time 3D echocardiography is that it extends the time required for diagnostic procedure and it demands higher level of training of the examiner.…”