Mitral Ebstein's Anomaly Modified with a Scarred Rhabdomyoma in Tuberous Sclerosis: An Extremely Rare Cause of Mitral Insufficiency

Abstract

We present an extremely rare case of mitral Ebstein's anomaly that resulted in severe mitral regurgitation (MR). A 41-year-old woman with a history of tuberous sclerosis underwent surgery. Preoperatively, it was assumed that MR had occurred due to leaflet tethering related to left ventricular posterior wall motion asynergy due to a scarred rhabdomyoma. However, surgical inspection revealed a dysplastic posterior leaflet adhering to the ventricular wall, which was completely covered by the endocardium. Both congenital mitral Ebstein's anomaly and acquired wall motion abnormality due to a scarred rhabdomyoma may have contributed to the development of severe MR in this case.

Keywords: Ebstein's anomaly; delamination failure; mitral regurgitation; mitral valve; plastering; tuberous sclerosis.

Figure 1.

Transthoracic echocardiography of a 41-year-old woman with mitral Ebstein’s anomaly. The parasternal long-axis view shows that the hinge point of the posterior mitral leaflet is apically displaced due to adhesion to the ventricular wall. As a result, the coaptation point is displaced downward and towards the left ventricular apex.

Figure 2.

Exercise stress echocardiography of a 41-year-old woman with mitral Ebstein’s anomaly. Color Doppler echocardiography shows that the proximal isovelocity surface area and color signal of the mitral regurgitation gradually deteriorated during stepwise exercise stress (A-D), which ultimately resulted in severe mitral regurgitation at peak exercise (D).

Figure 3.

Transesophageal echocardiography of a 41-year-old woman with mitral Ebstein’s anomaly. (A) A mid-esophageal horizontal view shows a thickened posterior mitral leaflet. (B) Color Doppler imaging shows severe eccentric regurgitant jet along the left atrial wall.

Figure 4.

Surgical pictures of a 41-year-old woman with mitral Ebstein's anomaly and pictures from a normal subject. (A) Surgical inspection revealed an elongated anterior mitral leaflet with an intact sub-valvular apparatus. In contrast, the dysplastic posterior mitral leaflet was plastered to the left ventricular posterior wall. Moreover, the subvalvular apparatus of the middle portion of the leaflet was absent. (B) A normal mitral valve has sufficient leaflet volume to cover the entire mitral orifice. Of note, the sub-valvular apparatus is observed to be clearly attached to both mitral leaflets.

Figure 5.

Clinical and anatomical characteristics of classical Ebstein’s anomaly and mitral Ebstein’s anomaly