PARIS (Reuters) -French artificial heart maker Carmat said on Monday it had implanted seven of its Aeson devices as part of a clinical study in Paris, sending its shares up almost 8%. “This ramp-up is the result of growing experience in patient selection and attests to the steep learning curve of the surgical procedure,” Professor Christian Latremouille, director of surgical affairs at Carmat, said in a press release. The clinical study, called EFICAS, is a prospective study designed to include 52 patients eligible for transplants, currently enrolled by a network of six French cardiology centres, Carmat said.