When Blake Busmire arrived at New York City’s Mount Sinai Medical Center on May 8, the then 8-year-old was battered, bloated and his heart was quickly failing.

Doctors quickly inserted an experimental device into his chest called the Berlin Heart to do the work for his own very weak heart.

PHOTO ESSAY: Click here to see photos of Blake before and after his heart transplant.

The device saved Blake's life, according to Dr. Umesh Joashi, a cardiac intensivist at Mount Sinai. But the fix was only temporary.

So for four months, Blake passed the time in the pediatric intensive care unit playing video games, sketching comic book characters and completing his schoolwork as the hospital searched for a heart.

On Sept. 18, four days after Blake's 9th birthday, the family got the news they were waiting for."I felt like my God, finally," Blake told FOXNews.com Tuesday just before heading home to the Rochester, N.Y. suburb of Farmington. "I thought I was going to be here forever."

A New Heart for Blake

Blake, who suffers from a rare form of muscular dystrophy that caused his heart to fail, said he and his mom Regina were "out of control" when told a heart had been found.

His mom agreed.

"I was crazy excited," Regina Busmire said. "I couldn't believe it happened. Blake was still opening presents from his birthday and the nurse pulled me aside to tell me. I just grabbed her and cried."

VIDEO: Click here to see how Blake is recovering.

Wearing the same ear-to-ear grin he sported back in July while talking about the new heart he hoped to get, Blake, bouncing around from standing, to his bed, before settling into a chair, quickly shot off a list of things he hoped to do Wednesday once he arrived home.

"I'm going to go crazy, play video games and sleep in my own bed," said Blake, who added that he might want to try sword fighting.

Blake's Journey to Mount Sinai

In the first week of May, Blake was airlifted from Rochester to Mount Sinai Hospital in New York City. Both sides of his heart had failed.

Doctors immediately placed him on an extracorporeal membrane oxygenation (ECMO) machine, which provides cardiac and respiratory support to patients whose heart and lungs are no longer functioning.

But the ECMO is only good for short-term use, so he was transitioned onto the Berlin Heart, which is not approved by the U.S. Food and Drug Administration for use in the U.S.

The German company Berlin Heart AG was formed in 1997. Its three heart devices have been used widely across Europe for several years.

Because it’s not FDA approved, U.S. doctors must apply for “compassionate” use of the device in cases such as Blake’s.

Mount Sinai is one of 10 centers in North America that are part of a test program for the Berlin Heart, Joashi said.

"He had a very smooth run on the device, no complications," he said "He’s active. He’s able to walk around. He’s been very lucky he hasn’t had any complications."

By all accounts, the heart transplant was successful, but Blake will continue to be monitored and will need to continue taking anti-rejection medication indefinitely.

"He went from being bed-bound and critically unwell, basically with his organs failing, to a relatively well individual," Joashi said. "He was in really good shape when he got his transplant, which makes a big difference"

Once home, Blake may resume normal activities, Joashi said. He plans to return to school within 1-2 months and he can even play baseball again.

"Obviously, playing contact sports are probably not a good idea, but technically there is no limitation to what he can do," Joashi said.

Transplanted hearts usually last for 15-20 years before a new heart is needed. But improvements in anti-rejection medications are being made every day and it's possible Blake's heart will last considerably longer than 20 years, Joashi said.

The Journey Home

Regina and Blake Busmire shared a teary-eyed goodbye with staff at Mount Sinai before jumping into a van and making the six-hour return trip to their home in western New York state.

"It's very exciting but it's kind of sad to say goodbye to all the good people here," said Blake, who took his Berlin Heart home with him.

"Everybody here is so wonderful and we will be back to visit without doctors appointments to see everyone," Regina Busmire added. "It’s been a wonderful experience."

Joashi said he will miss Blake as well.

"This is the best possible thing that could’ve happened," he said. "He’s got a heart transplant. We’re all really delighted. But he’s been here for six months and he’s part of the furniture, as was his mother. So they’ll be sadly missed."