In such patients, the interventricular defect is usually small, and shunting is limited by tendinous cords tethering the bridging leaflets.
In the most severe cases, the free edges of the leaflets are adherent to the subvalvar muscle with no intervening tendinous cords.
Note the tendinous cords from the tricuspid valve connecting to a single papillary muscle.
This had a large flat abnormal posterolateral papillary muscle an abnormal insertion of the tendinous cords.
At surgery, one of the six patients with a diagnosis of rupture was found to have only elongation of the tendinous cords.
Opened tricuspid valve showing shortened tendinous cords, but no formation of a muscular arcade.
The tendinous cords are implanted on the subvalvar muscle and, in consequence, their insertion is more posterior and higher than normal.
The tendinous cords of the septal leaflet were lengthened by interposing a short segment of 4-0 expanded polytetrafluoroethylene suture.