Looking at 7-month-old Santa Clarita baby Chase Sime, you would have no idea that he was born with a heart defect.

Born on March 6, 2018, Chase was welcomed to the world three weeks early. After four days of being in the neonatal intensive care unit, his parents, Vanessa and Dean Sime, took Chase home to begin raising the new addition to their family.

As with most babies, Chase was taken to his doctor three weeks later for a wellness check, where his parents received shocking news.

Chase was diagnosed with a heart defect called total anomalous pulmonary venous return (TAPVR).

TAPVR is a birth defect of the heart in which the veins bringing blood back from the lungs don’t connect to the left atrium like usual. Instead they go to the heart by way of an abnormal connection, according to the Centers for Disease Control and Prevention.                                              

Because of this, Chase was not getting enough oxygen to his heart, which also had a hole in it.

“It’s a really shocking thing to happen; it comes out of the blue,” said Bob Larlee, Chase’s grandfather. “You don’t see it coming, you don’t think it’s going to happen to you, and when it does, you rally as a family in a way that you never thought possible.”

As Chase experienced his first days of life in a hospital room, hooked up to all sorts of machines, fighting for his life, he underwent open heart surgery.

Weeks later, baby Chase defied all odds when doctors realized that his body had created a detour called a collateral vein pop off, where a pulmonary vein grew in front of the blockage, going around it and attaching to the heart.

“That’s kind of a miracle that it happened, but that miracle would have never had an opportunity to happen if it wasn’t for all of the work that the Heart Association has done,” said Larlee.

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As a longtime Santa Clarita resident, Chase’s grandfather served on the American Heart Association board of directors for five years until 2013. He then volunteered in honor of his father, who died of a heart attack.

Not knowing he would be volunteering again to help fight for a healthy future for his grandson, Larlee became the leader of the family during this difficult time.

“It felt really good being involved the first time,” he said. “But now that I have a grandson in the throes of a heart problem, I’m not a spectator anymore. I’m one of the families going through this. I’m going to do everything I can to turn the love I have for Chase into giving back. That’s my goal. It’s a journey we’re on together.”

And although Chase recovered and doctors are thrilled with his complete turnaround, he’s still unlike any other baby.

“There are some physical delays because we weren’t allowed to pick him up around his chest. There was also no tummy time,” said his mother. “He’s just a couple of months behind, but he’s 7 months now and he’s growing beautifully.”

Chase has a long road of checkups ahead of him, but as of right now, his family says that doctors do not foresee any more issues.

“Even though Chase is fine now, it’s still a battle every day because you think of what could’ve happened. I hear these stories and I think how lucky we are,” said Sime.

In Los Angeles County, heart disease and stroke are the No. 1 and No. 2 killers. Heart disease, stroke and other cardiovascular diseases claim the lives of more than 830,000 men, women and children every year, according to the American Heart Association.

Because of this, Chase’s family will be participating in the Santa Clarita Heart Walk to raise funds for the American Heart Association in their efforts to continue their work against heart disease.

“We’re supporting the Heart Association because that work ultimately is what saved his life,” said his grandfather.

For more information about the Santa Clarita Heart Walk, visit the website here.

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