Emergency calls for cardiac arrest at the home of Sen. Lindsey Graham (R-SC) on Saturday night have fueled speculation that the South Carolina Republican died of a heart attack, a diagnosis that aligns with a family history of cardiovascular disease.

Graham’s staff issued a statement in the early hours of Sunday morning saying that the senior senator from South Carolina died following a “brief and sudden illness.” Previously reported dispatch audio details that emergency medical services personnel responded to a call of cardiac arrest, the medical term for a heart attack, at Graham’s residence late Saturday evening.