About The On-X Heart Valve


In the realm of mechanical heart valves, the On-X valve stands apart from all the rest. No other valve is so comprehensive in its approach to maximizing benefits for the patient.

This valve is the culmination of the long and productive careers of Jack Bokros, Ph.D. and his long-time associates. Their involvement began in the late 1960′s when Dr. Bokros and Dr. Vincent Gott collaborated to introduce pyrolytic carbon to the heart valve industry.

Read More about The On-X Heart Valve Story: Evolution of the mechanical heart valve.

Although they sensed that carbon held the potential for durable and thrombosis-free prosthetic valves, designs were limited by the properties of the carbon. Manufacturers successfully produced durable valves but were unable to incorporate fluid-dynamic shapes to reduce turbulence. These carbon mechanical valves required anticoagulation therapy for prevention of thrombosis.

In the early 1990′s the Bokros team patented new technologies to produce 100% pure carbon, eliminating the silicon alloying that is used with other valves. Importantly, the new carbon has great flexural strength, enabling the incorporation of advanced new features.

Because of their extensive design and manufacturing experience, the Bokros team was uniquely capable of capitalizing on these new options. The properties of On-X carbon inspired the team to revive the quest for the ultimate heart valve replacement— a valve that will last a lifetime with minimal anticoagulation requirements.

The result of that revitalized effort is the On-X Prosthetic Heart Valve. The valve is now at the top of the class in virtually every performance category, validating the effects of the many innovative design enhancements conceived by the design team.

Read more about the On-X Heart valve design and features.


Heart disease affects more than 5 million people each year and some require heart valve replacement surgery. The
aortic valve may need to be replaced in order to treat aortic stenosis or aortic regurgitation.


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Patient Stories about the On-X Heart Valve

The On-X Heart Valve Patient Guide

For Patient, Technical, and
General Inquiries

Mark Spindler
(512) 831-6557