Cytomegalovirus, a common virus among pigs, may have been one of several factors in the death of the patient who received the first genetically modified heart, USAToday reported May 5.
David Bennett, 57, of Maryland received the heart in a historic procedure Jan. 7 at Baltimore-based University of Maryland. Officials confirmed he died on March 8.
An autopsy suggested that while the pig heart had been pumping well, the buildup of scar tissue was thickening the organ and preventing it from fully relaxing after pushing blood through. A PCR analysis of tissue from the heart showed some viral DNA, though researchers found no clear signs of infection of the pig virus.
Dr. Muhammad Mohiuddin, co-leader of the team that performed the transplant, told USAToday the virus clearly came from the pig, even though it was tested using "all available testing methods" before the procedure.
Dr. Mohiuddin added while no scientific evidence suggests a pig cytomegalovirus infection could cause the thickening seen in Mr. Bennett's heart, it can't entirely be ruled out.