Anomalous mitral ‘cleft’ with abnormal ventriculo-arterial connection: Anatomical findings and surgical implications

Abstract

Seven specimens with a 'cleft' mitral valve associated with anomalous chordal fixation and abnormal ventriculo-arterial connection are presented. Four were associated with a discordant ventriculo-arterial connection, two with double-outlet right ventricle, and one with double-outlet left ventricle. In six the chordae from the cleft were attached to the anterior border of a small ventricular septal defect. In the seventh the chordae were attached to an accessory papillary muscle in the left ventricular outflow tract. These clefts differ from those of atrioventricular defects. The cleft is more anterior, there are no septal defects of the atrioventricular canal type, and no deficiency of the basal ventricular septum. Mitral regurgitation or left ventricular outlet obstruction are possible consequences of the anomaly.

Characteristics and management of cleft mitral valve

“…A relatively uncommon lesion, such as a cleft of the mitral valve (MV), is morphologically different from a cleft of the left-sided valve of an atrioventricular (AV) septal defect because of the absence of a common AV junction (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11). It is observed when there is mitral regurgitation (MR), subaortic stenosis, or associated lesions (1-3,6 -8).…”

Cleft of the mitral valve in patients with Down's syndrome

“…A cleft of the mitral valve is commonly associated with other cardiac anomalies, 2,3,5,6,8 often a ventricular septal defect, 2,3,7,8 as 3 of our 5 patients. However, the type of ventricular septal defect associated with a cleft of the mitral valve differs markedly from the ventricular component of atrioventricular septal defect.…”

“…The cleft of the mitral valve can cause mitral regurgitation and left ventricular outlet obstruction. 2,[5][6][7] However, in our 5 patients with Down's syndrome and cleft of the mitral valve, surgical repair of the cleft was not indicated. Mild mitral regurgitation was found in 3 of them whereas none had subaortic obstruction.…”

“…Atrioventricular septal defect is the commonest cardiac surgical lesion associated with Down's syndrome. 1 A cleft in the mitral valve represents an uncommon congenital cardiac anomaly, involving almost always the anterior leaflet, [2][3][4][5][6][7][8][9][10] although a cleft in the posterior (mural) leaflet has been described. 9 It is important to distinguish a cleft in a normal mitral valve from the cleft seen with atrioventri cular septal defect because the conduction axis in atrioventri cular septal defect is exposed on the crest of the inlet ventricular septal defect during surgical repair.…”