After France-based Carmat implanted the first artificial heart in a patient last week, the medical technology company saw its stocks soar up to 43%, Bloomberg reported. Carmat said that the surgery happened last week, with the patient already talking with his family two days after the operation.

The report said Carmat increased 27% to €130.50 as of this morning in Paris. The rise gave the French firm a market value of €553.7 million or $757.4 million, making it the largest intraday gain in three months, the report said. Carmat's stock had declined 19% this year before today.

Based in Velizy-Villacoublay near Paris, Carmat made the prosthetic heart for those with terminal heart failure and where getting a human heart for transplant is impossible. Carmat was allowed by regulators to test the prosthetic organ by having it implanted in four patients in France.  

The report cited Carmat CEO Marcello Conviti as saying in an interview this year that the artificial heart, which is designed to be like the of the human heart as much as possible, weighs 750 grams or 1.7 pounds. It will cost anywhere from € 140,000 to €160,000. The prosthetic organ mimics the contraction of the heart and also has right and left ventricles.

Carmat was founded by Alain Carpentier, a cardiac surgeon who had successfully developed heart valves before.

Information from its website showed that the financial partner of Carmat is Bpifrance, a European company whose three functions include aiding and supporting innovation, serving as a guarantor of bank funds and contributions from equity organizations and funding investments and the commercial cycle together with lenders.

A Reuters report on December 21 said the company may look for an injection of funds from fresh investors so it would be able to tap the multibillion euro global market. Citing an interview with Carmat Co-Founder Philippe Pouletty with the Le Monde newspaper, the report quoted him as saying, "We could, at some point, call on new investors. Our aim, if possible, is to remain independent."