Late Sen. Lindsey Graham's (R-SC) office released the medical examiner's preliminary findings about his cause of death on Sunday evening.
The Medical Examiner of the District of Columbia said in their report that Graham suffered from an "aortic dissection due to Arteriosclerotic Cardiovascular Disease," reported Max Cohen of Punchbowl News. Said another way, Graham appears to have died from a rupture in his aorta that was caused by fatty plaques that restricted blood flow.
"The death certificate will be pending until all toxicological and microscopic testing are finalized, and at that point, the death certificate will be updated to reflect the cause of death and appropriately classify the manner of death," reads a statement from the medical examiner's office.
Graham died late Saturday night after being rushed from his Washington, D.C., residence to George Washington University Hospital, according to reports.