When most people hear about a heart transplant they assume something was taken out first.

But apparently, that's not always the case.

Tyson Smith, a 36-year-old San Diego man with an enlarged heart, received a heterotopic heart transplantation or "piggyback" transplant, essentially adding another heart to his weak one, allowing the pair to share the work. Tyson's original heart was so weak doctors thought he had only a month to live, and he was sleeping up to 20 hours per day, according to CBS 8.

Smith's doctor, who has been performing heart transplants for 30 years, has only performed this procedure five times.

Dr. Jack Copeland, director of cardiac transplantation and mechanical circulatory support at UC San Diego Health System, says that the procedure increases patients life-expectancy to 10 years, according to Fox News.

Incredibly, the procedure also saved a tremendous amount of the cost. While a regular transplant would cost close to $500,000, the "piggyback" operation cut the price to $100,000, according to CBS 8.

Video of the two hearts beating together below.

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