A 17 year –old- woman presented with recent dyspnea on exertion, New York Heart Association (NYHA) functional class II. Physical examination showed no cyanosis or clubbing of fingers or toes. Transthoracic echocardiography revealed mild right ventricular enlargement associated with moderate tricuspid regurgitation.

Figure 1 Echocardiography Image

Based on the transthoracic and transesophageal echocardiography what is the diagnosis? Answer: Parachute abnormality of the tricuspid valve.

Editorial comment: A parachute deformity of an atrioventricular valve occurs when the chordae tendinea arise from a single papillary muscle or muscle group. Parachute abnormality of the tricuspid valve has rarely been reported. Parachute abnormality of mitral valve is a known entity, and is usually associated with left sided obstructive lesions. Sometimes, the normal number of papillary muscles is seen, but one muscle is much larger than its peers and shows some characteristic features.It is known as a parachute-like asymmetric valve and has been well described in the mitral position and rarely in tricuspid valve.We think that parachute anomalies of the tricuspid valve are more frequent than published reports indicate. This is probably because the clinical findings and pathological anatomical features are masked by the severe anatomical lesions with which they are usually associated (1,2).