Abstract: A method and device for protecting the circulatory system of a patient from incurring injury from inadvertent passage of air into the aorta when elevated with respect to and supported by a heart-lung machine and associated nonocclusive pump. This device and method provides positioning a valve means having unidirectional flow properties within the extracorporeal blood line connecting the heart-lung machine and patient. The valve is configured to offer nominal resistance against blood being returned to the patient, while blocking blood flow from the patient to the heart-lung machine.

Abstract: An integral blood pressure sensor for a cardiac prosthesis of the type having a fluid chamber and a blood chamber separated by a flexible diaphragm which is actuated by a drive fluid pulsatingly supplied to the fluid chamber for pumping blood from the blood chamber. The blood pressure sensor includes at least one transducer integral with a wall of the blood chamber and in pressure-sensing relation to the interior of the chamber. The invention also includes a method of manufacturing a cardiac prosthesis having an integral blood pressure sensor.