The requirement for patients with mechanical heart valves to take routine doses of anticoagulant therapy including warfarin has hitherto been pretty much set in stone. New clinical data has been used to support a modification in the labelling claims of one such valve, the On-X® Life Technologies Inc (LTI) mechanical aortic valve, which means patients can be managed at near-normal levels.
Background
Despite advances in heart valve technology there remains significant demand for mechanical heart valves, based on their durability compared with tissue valves. Patients under the age of 65, and especially those in their fifties, in need of a replacement heart valve, are less likely to opt for tissue valves than their mechanical equivalent because tissue valves only last between eight and sixteen years.
Yet, while mechanical valves sound like the answer, their use has always demanded significant blood thinning cocktails, which are not always well tolerated and carry with them a significant risk of bleeding. This use of thinners has been demanded because mechanical valves have less thromboresistant surfaces than tissue valves and work in a more mechanical, less natural way, causing blood flow to be more turbulent and consequently more likely to generate thrombi than a natural equivalent.
So, what the clever folk at On-X are claiming lies beneath their new-found claims of thromboresistance are a couple of characteristics. Firstly their proprietary medical grade carbon technology, so-called On-X pure pyrolytic carbon has a claimed, particularly thromboresistant surface. And secondly, by virtue of its comparatively high strength, it has enabled the company to make significant valve design changes that have resulted in a prosthesis that acts more like a natural valve in its treatment of blood. The valve seemingly avoids the turbulence and blood damage commonly produced by other mechanical heart valve prostheses and with that comes a reduced potential for life-threatening blood clots, with the consequent reduction in anticoagulation.
Physician comments
“I think this is a potential game-changing, paradigm-shifting opportunity in clinical cardiac medicine and in valve disease in general,” said Mohan Sathyamoorthy, M.D., cardiologist. “I think the really exciting aspect is the potential to reduce anticoagulation burden.”
Company comments
“On-X is the first prosthetic heart valve designed to combine the durability of a mechanical valve with the reduced complication rates of tissue valves,” said Jack Bokros, Ph.D., On-X LTI’s founder.
Link to Cardiodevicenews item here.
Source: On-X Life Technologies, Inc., Business Wire
published: January 15, 2014 in: Approval/Clearance, Cardio, Clinical Studies/Trials