Mitral Valve Repair
Mitral valve repair procedures are typically performed through a 3 to 10 inch chest incision (sternotomy). The surgery is usually an open heart procedure making it necessary to stop the heart and place the patient on bypass. Stopping the heart increases the risk for complications and can be a concern with elderly patients and those with complex health problems. If the repaired valve is still leaking after restarting the patient’s heart, the heart must be stopped once again to correct the leakage.
One approach to repairing a prolapsed leaflet is to remove excess leaflet tissue along with the damaged chordae (called resecting) from the leaflet and suturing the edges of the resected area together. Leaflets that are resected often are stiff, less mobile and do not fit as well against the other leaflet. Additionally, removing excess tissue in many cases causes the overall valve leaflet area to decrease while the valve opening (called the annulus) remains the same size. This often causes leakage – like using a smaller cork when the bottle opening has not changed. To correct this, a ring is usually implanted to decrease the diameter of the annular opening if stretching has occurred in patients with enlarged left ventricles.
A technique that is gaining in popularity is repairing the mitral valve by replacing the stretched or broken chordae without resecting the prolapsed leaflet. The damaged chordae are replaced with ePTFE suture material. The sutures are anchored in the papillary muscle and then placed through the edge of the prolapsed leaflet. When the suture is tightened, the prolapsed portion of the leaflet is now in the left ventricle and the leaflets once again fit together. The advantage to this technique is that it preserves the leaflet, and usually results in a larger area for the blood to flow through. By not resecting the valve, the original anatomy of the valve is preserved and in essence, the surgeon is fixing the structure in the valve that is broken.
NeoChord Artificial Chordae Delivery System, Model DS1000
NeoChord has developed a disposable device, called the NeoChord DS1000, which makes it possible to replace damaged chordae through a small incision while the heart is beating. Using echocardiographic images for guidance, the ePTFE suture is placed and tensioned just enough to reduce the mitral regurgitation. The DS1000 is commercially available outside of the United States. A clinical study is ongoing within the United States to evaluate the use of the NeoChord DS1000.