Soldier claims COVID vaccine caused heart attacks, stroke | Cuomo Army National Guard Specialist Karoline Stancik, 24, says she’s in $70,000 of medical debt after being hospitalized for heart complications. She suffered three heart attacks and a stroke after receiving the Moderna COVID-19 vaccine. According to a new report, the Department of Defense acknowledges that Stancik’s diagnosis of postural orthostatic tachycardia syndrome, or “POTS,” may have been caused by the vaccine.