French company Carmat fits second patient with artificial heart

* The company confirms media reports, shares rise

* Carmat's device aims to serve as a permanent heart

* Two more patients will be fitted with the device (Adds health ministry statement, analyst comment)

By Natalie Huet

PARIS, Sept 8 (Reuters) - French company Carmat said on Monday it had fitted a second patient with one of its artificial hearts and would continue clinical trials on two more patients.

The French health ministry said the operation had been carried out on Aug. 5 at a hospital in Nantes in the west of the country. Neither the ministry nor Carmat gave any details about the patient.

The device, which mimics a real heart using biological materials and sensors, is designed as a permanent implant that can extend life for patients without them having to wait for a donor. It also aims to reduce the side-effects often associated with heart transplants, such as blood clots and rejection.

The patients selected by Carmat for its first clinical trials suffer from terminal heart failure - when the heart can no longer pump enough blood to sustain the body - and have only a few weeks, or even days, to live.

The success of these initial trials will hinge on whether Carmat's patients survive with the implant for at least a month.

Arnaud Guerin, biotech stock analyst at brokerage firm Portzamparc, said if the date given by the health ministry was correct, that would be good news because it would mean the patient was beating the one-month target.

But he said that doctors and investors alike would be on the lookout for other indicators of success, such as how easily surgeons managed to implant the artificial heart and how quickly the patient could stop taking anticoagulants afterwards.

Carmat's shares shot up by nearly 19 percent on Friday following French media reports that doctors had implanted a second artificial heart made by the company. They rose as much as 3.7 percent after the company's confirmation.

Both Carmat and the hospital declined to provide any more details about the operation. French Health Minister Marisol Touraine's office did not pick up calls.

Carmat said in its statement it did not plan to publish any information on the results of its study until it is completed.

If the results of these first safety tests are positive, Carmat has said it would fit the device into about 20 patients with less severe heart failure, with an aim to request the right to market its device in Europe by early 2015.

Patient enrollment had been put on hold in March after the first person to be implanted with the device, a 76-year-old man, died two and a half months after his operation.

Carmat's device weighs about 900g (around 2 lb)- nearly three times more than an average healthy human heart. It mimics heart muscle contractions and contains sensors that adapt the blood flow to the patient's movements.

It is powered by external, wearable lithium-ion batteries. Inside the heart, surfaces that come into contact with human blood are made partly from bovine tissue instead of synthetic materials such as plastic that can cause blood clots.

It is expected to cost 140,000 euros to 180,000 euros ($181,000-$233,000) in Europe.

Among Carmat's competitors for artificial heart implants are privately-held SynCardia Systems and Abiomed (NasdaqGS: ABMD - news) , both of the United States. (1 US dollar = 0.7724 euro) (Editing by Susan Thomas and Jane Merriman)