(CNN) -

A Florida cardiologist could have his medical license revoked by state authorities who have accused him of performing illegal stem cell therapy on a patient who died during the procedure.

Florida's Department of Health ordered the emergency suspension of Zannos Grekos' medical license Wednesday, accusing the Bonita Springs doctor of violating an emergency order against using stem cell treatments in Florida and causing the death of an unidentified elderly patient. Grekos can appeal the order.

According to the license suspension order, Grekos performed a stem cell treatment this month on the patient, who was suffering from pulmonary hypertension and pulmonary fibrosis. Both diseases restrict blood flow to the heart.

"During said stem cell treatment, patient R.P. suffered a cardiac arrest and died," the suspension order said.

CNN first investigated Grekos' activities in 2009, when he said he was using stem cell therapy for a company called Regenocyte Therapeutic. His profile, listed on the company's website, describes Grekos as having "extensive experience in the field of stem cell therapy" and says he "was recently appointed to the Science Advisory Board of the United States' Repair Stem Cell Institute."

At the time of CNN's interview, Grekos said he extracted stem cells from patients and then sent the blood to Israel for laboratory processing. That processing, he said, resulted in "regenocytes," which he said would help heal crippling diseases, mostly associated with lung problems.

The president of the International Society of Stem Cell Research, Dr. Irving Weissman, told CNN at the time that "there is no such cell."

"There is nothing called a regenocyte," he said.

After CNN's initial report, Grekos said the name was "advertising" and was not intended to be scientific.

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Patient dies during procedure