Elon Musk responded to an article about the cardiac arrest of Bronny James on Tuesday by irresponsibly invoking COVID vaccines. “We cannot ascribe everything to the vaccine, but, by the same token, we cannot ascribe nothing,” Musk wrote, adding: “Myocarditis is a known side-effect” of the COVID shot. A fact-check through the platform’s Community Notes feature soon appeared alongside Musk’s tweet noting that the risk of myocarditis, a rare condition characterized by inflammation of heart muscle, is much higher for patients after a COVID infection rather than after a COVID vaccine. Without explanation, the fact-checking post was deleted from Musk’s tweet, which as of Wednesday still remains on his newly rebranded X platform without any kind of qualification. It’s not clear if Bronny James—LeBron James’ son—suffers myocarditis. He reportedly collapsed during a basketball workout at the University of Southern California on Monday.