The French company is conducting trials of its heart device, which is designed as a permanent implant to extend the life of patients without them having to wait for a human heart donor.
Carmat’s 1st transplant patient, a 76-year-old man, died in March last year, 2½ months after his operation.
A 2nd patient died May 2, 9 months after receiving the transplant. Carmat said his death was due to a technical problem with the controls of the motor.
A 3rd patient, who was fitted with the device April 8, is undertaking physiotherapy.
"The 4th patient will undergo surgery once everything has been analyzed and the engineers are able to tell me, ‘Go ahead, we’ve checked everything, everything’s fixed, the new device won’t [encounter] the same issues as the previous ones,’" Alain Carpentier, who invented the device, told BFM.
If the 3rd and 4th patients survive the transplants, Carmat will launch wider clinical tests involving about 20 patients spread across Europe, a prerequisite to its commercialisation within the European Union.
Shares in Carmat were up 1.5% at 15:26 GMT.