The video above is jarring and very graphic, showing two hearts pumping at once. It's also beautiful because without that extra heart, a man wouldn't be alive. Tyson Smith, the man whose hearts are shown above, went through a rare surgery that's called a heterotopic heart transplant. In the surgery, doctors add another heart to the right side of his chest to share the work and get the job done.

In Smith's case, he couldn't replace his own heart with the new one, he needed both:

"Even though Mr. Smith was facing death, he could not have a standard heart transplant," explained Dr. Michael Madani, associate professor of surgery and co-director of the UC San Diego Sulpizio Cardiovascular Center, in the release. "Removing the old heart and replacing it with a new heart would have caused the new heart to fail because resistance to flow in his lungs-called pulmonary hypertension-was so high. But together, the two hearts share the work and get the job done."

Doctors say it's an incredibly rare procedure but one "worth having in the tool kit". Amazing. [LaJolla PatchThanks Snake Charmer!]