On February 11, 2006, Cheney shot a hunting partner in the face, nearly killing him. When Harry M. Whittington, a prominent attorney in Austin, arrived at Armstrong Ranch in the very southeastern tip of Texas, he had a deep connection not to Cheney, but instead to a few other notorious Republicans of the George W. Bush era. One was Bush himself, who knew Whittington from their days as good ol’ boys—when Bush was still governor in 1999, he picked Whittington to temporarily run the Texas Funeral Service Commission. Whittington got severely fucked up by Cheney. He may or may not have had a mild heart attack caused by an irregular heartbeat triggered by buckshot in his chest.
So what if Whittington died?
IIRC, most of the pellets entered his chest. And he did indeed suffer a heart attack, as well as a collapsed lung
After it happened, my dad (an engineer, shooter, and wilderness first responder) and brother ran the math on the type of shot, the firearm involved, and the reported injuries, and concluded that the "accident" was at much closer range than reported. IIRC, there were some experts who did similary studies at the time and reached similar conclusions. They all concluded that, rather than the reported 30 yards, the shooting actually took place at 10 yards, and that there alcohol was almost certainly involved at that close of range. In addition, there appears to have been some question about the timing of the accident, and there may have been a delay in calling the local authorities to allow Cheney to sober up.
Given all that, it's quite plausable that the shot could have easily been fatal.
Had it been, and had the ambulance actually been delayed, if and when the details come out, it will be quite bad for Cheney.