Homemade "artificial hearts" have saved two patients with advanced cardiac failure in North China's Tianjin municipality, and an activity was held Friday to celebrate the success, more than 100 days after the surgeries.

Doctors at the TEDA International Cardiovascular Hospital implanted the HeartCon, a ventricular assist device developed and patented exclusively by Chinese professionals with "rocket science," for the two patients in March.

The man, 39, and the woman, 62, lived with advanced dilated cardiomyopathy, a condition that causes poor heart function, chest distress and shortness of breath, and were under constant threat of imminent death from heart failure.

After the successful implantation, the man now exercises by walking at least 20,000 steps every day and the woman, who is the first female to receive such a device in China, started her daily exercise routine with a goal of at least 10,000 steps.

The HeartCon is considered the first of its kind in China, with its parts also made in China. It was developed through the joint efforts of the hospital and the China Academy of Launch Vehicle Technology, a developer of the country's rockets.

The device is a titanium alloy system of hybrid magnetic-hydrodynamic impeller suspension weighing 180g. Powered by two batteries connected to the three-core driveline, it delivers 1-10L of blood per minute.

The hospital and the academy started to cooperate on the device in 2009, and the HeartCon was implanted in a sheep in 2013. It lived 120 days in good health after the procedure.

The animal series of tests using the HeartCon started in October 2017. All six sheep receiving the HeartCon survived more than 90 days, with the longest survival lasting 180 days.

The device was submitted for special review and approval procedure for innovative medical devices after approval from the Chinese Food and Drug Administration in June 2018.