Currently, mitral valve repair (MVr) success for primary mitral regurgitation relies mainly on surgeon's expertise and major heterogeneities are observe concerning MVr rate, technics, and results. MVr success is estimated by a morphological echocardiographic assessment after aortic unclamping. To date, coaptation forces have been poorly characterized.

We developed a device allowing a precise morphologic and qualitative assessment of coaptation.

A first prototype allowing three-dimensional mapping of coaptation forces was developed and a provisional patent was filed. A number of features informed the design of the new device, including force sensitivity, flexibility, and biocompatibility. Varying sensing technologies were screened (including piezo-electric, piezo-resistive, and resistive sensors), and a specific device to hold the sensor was designed and prototyped.

The first generation of prototype was tested on a porcine ex vivo beating heart model. The device was inserted between the mitral leaflet through a left atrial incision between two running sutures. The sensor was positioned and connected to a custom-made acquisition system. The coaptation signal was recorded in normal valves and after creation of a posterior central prolapse. We were able to obtain precise surface mapping of mitral coaptation forces in this model. The coaptation signal was notably more intense in the normal valve compare to the prolapsed valve in otherwise similar hemodynamic conditions (Fig. 1).

A mapping of coaptation forces along the entire mitral valve surface can be achieved with the method and device we have developed. This technology may be useful to assist surgeons during MVr while providing real-time objective measurement in support of the conventional intraoperative morphological assessment. An extensive development roadmap has been developed and is being put in place to move our invention toward clinical trials.