How Does A Rattlesnake Kill Its Prey?

The many species of rattlesnakes in the United States are pit vipers. They have a distinctly triangular head and narrow "neck" with two shallow pits between their eyes.
Like all snakes, rattlers are deaf. They hunt by smell, vibration, and sensing the victim's body heat with the special pits.
The venom is a neurotoxin that paralyses the victim and begins the cellular breakdown needed for the snake's digestive process.
When the snake "strikes," two hollow, venom-filled fangs unfold from the roof if its mouth to puncture the victim's skin. The snake waits for the victim to become paralysed then swallows it whole.
After my cats alerted me to the presence of a rattler in my yard, I got a shovel out of a hot shed to dispatch it; you must severe the snake's head with one, decisive shop. The snake was not moving  when I approached, but as I passed the warm shovel over its head, it sensed the heat, assumed the strike position, and began rattling.