A ruptured aorta kills very quickly. I knew a couple who had a son rather late in life, and he was their pride and joy. And, he was a good kid- except when he went drinking.
They had plenty of money, and they indulged him. They bought him one of those Plymouth Vipers- a fast car, borne for speed.
Late one night, after a lot of heavy drinking, he was driving home to his parents' house, and they lived in the country. And he apparently was speeding some. So, a cop tried to pull him over.
Now, this was a small town where everyone knew everyone. Trying to lose this cop by racing away was ridiculous and futile, but the alcohol on his brain said otherwise. So, the kid floored it. And I mean he took it over 100 mph.
Now, what the cop should have done is just let the kid go. He knew where he lived. He knew his parents. He didn't have to turn it into a high-speed chase. But, he did.
And just as the kid was reaching his house, which was his parent's house, he crashed into a telephone pole. And the impact ruptured his aorta. It happened right in front of his parents' house. They heard the crash. They looked outside, and they saw his car. His father went running out. And he was a rather old guy. I bet he hadn't run in years. And when he got to the car, he saw that his son was dead. He was already stark white from the blood loss. And he was dead. He ruptured his aorta. The boy was dead by the time the father got to the car.
The parents never recovered. The mother had to go on heavy-duty sedatives. Eventually, the father sued the policeman and the department for which he worked for the wrongful death of his son.
The above is a true story. But, I'll confess that I included it in my e-novel, My Stretch of Texas Ground, which is about a small town sheriff who has to contend with Islamic terrorists. It wasn't central to the story, only peripheral. Still, it's in there.
But, my point is that, in real life, this young guy died in less than a minute from a ruptured aorta. So, if Oswald was shot in that garage at 11:20, sustaining the trauma that was later described by Dr. Tom Shires, which included ruptured aorta and vena cava and superior mesenteric artery, and damage to spleen, pancreas, liver, and right kidney, how could he possibly have still been living, his heart beating, at 11:35?