A study of the mechanical properties of ePTFE suture used as artificial mitral chordae.

BACKGROUND AND AIM OF THE STUDY: We investigated the dimensional and mechanical properties of polyetetrafluorene (ePTFE) sutures used as artificial chordae during mitral valve repair.

METHODS

Mechanical properties of ePTFE synthetic chordae tendineae were tested with a servo hydraulic testing machine. Several different lengths from 2 to 14 cm were studied under both single and multiple mechanical traction.

RESULTS

The mechanical behavior of artificial chordae reveals that three centimeters is the length over which we observe a significant increase in stiffness. The chordae stiffness grows further at the length greater than seven centimeters following a low number of traction cycles.

CONCLUSION

The increase of the length of artificial ePTFE chordae is accompanied by an increasing stiffness that compromises the long-term resistance of the chordae. ePTFE length can alter the performance of artificial chordae. This suggests that mitral valve repairs which anchor ePTFE neochordae to the ventricular apex may have less durability than when anchored to the tips of the papillary muscles.