Hayden Panettiere's brother Jansen died from an enlarged heart, his family said. The condition can lead to heart failure and can affect all ages.

• Jensen Panettiere died from an enlarged heart, his family said in a statement to Insider.
• The 28-year-old was confirmed dead on Monday, February 20. He reportedly died earlier that weekend.

Jansen Panettiere — actor Hayden Panettiere's 28-year-old brother — died from an enlarged heart, his family said in a statement shared with Insider Monday.

"It is with great sorrow we share the tremendous, untimely loss of our beautiful Jansen," the statement, signed by Skip Panettiere, Lesley Vogel, and Hayden Panettiere, said.

"Though it offers little solace, the Medical Examiner reported Jansen's sudden passing was due to cardiomegaly (enlarged heart,) coupled with aortic valve complications," the family said.

According to the Mayo Clinic, an enlarged heart isn't a condition itself, but rather a symptom of something else like heart disease or short-term stress.

Cardiologist Dr. Shriprasad R. Deshpande, a member of the American Heart Association's Young Hearts Council, told Insider it's not unusual for a 28-year-old to be diagnosed with cardiomegaly, which can be related to genetics, though it's most likely to be found in people over 40.

"Aortic valve complications" could mean any issue related to the aortic valve, which the Mayo Clinic describes as the portal that keeps blood flowing in the right direction from the heart's lower left heart chamber through its main artery to the body, the aorta. A damaged or diseased aortic valve can block blood flow to the body or wrongly re-route it back into the left ventricle.

Deshpande said that heart valve leakage can lead to an enlarged heart because it forces the muscle to work harder.

If someone's heart is built differently, too, it can weaken the heart's pumping ability, causing it to swell and eventually leading to heart failure, added Deshpande, who's also the medical director of the Heart Transplant and Advanced Cardiac Therapies Program at Children's National Hospital.

Weakened heart muscle can also put people at risk for irregular heartbeats, which can lead to cardiac arrest or sudden death, he said.

"Having both cardiomegaly and aortic valve complications simultaneously represents an advanced stage of the condition that may be very challenging to manage and treat," he said.

Panettiere'ss "creative spirit will live forever in our hearts," his family said

The news of Panettiere's death was confirmed to CNN on February 20. Insider previously reported that he died that weekend.

"Jansen's heart could be seen in his eyes, and his charm in his brilliant, engaging smile; his soul in his masterful and revealing paintings, and the joy of life in his dry wit," the statement from Panettiere's family continued. "His charisma, warmth, compassion for others, and his creative spirit will live forever in our hearts and in the hearts of all whom he encountered."

Panettiere was an established voiceover actor, with his most notable roles in 2005's "Robots" and 2006's "Ice Age: The Meltdown." He also made guest appearances in TV shows like "Even Stevens," "Everybody Hates Chris," and Nickelodeon's "The X's."

He starred alongside his sister, Hayden, in the 2004 Disney Channel original movie "Tiger Cruise" and the 2005 sports comedy "Racing Stripes."

According to a biography on his website, Panettiere recently moved away from voice acting and turned toward creating art.

"After spending time in LA as an adult he was ridden with terrible anxiety and depression; this period in his life eventually produced a spiritual clarity that drove him to start painting his problems, one by one," his website said. "With more than 50 pieces, Jansen continues to heal himself as well as others with his visceral and emotive work."

It's important to know the symptoms of an enlarged heart

Deshpande, the cardiologist, said an enlarged heart can often be difficult to diagnose since symptoms like fatigue can present as other common conditions. He said parents and doctors should be aware of young people who are more tired than usual, or who seem to have asthma that doesn't respond to asthma medications. Other symptoms can include stomach pain after eating and a loss of appetite.

"Creating public awareness around this problem of the heart muscle leading to cardiomegaly is really important," he said.