What is an enlarged heart? Jansen Panettiere’s cause of death revealed by family

Actor Jansen Panettiere, known for his roles in The Walking Dead and Ice Age: The Meltdown, died suddenly on 19 February at the age of 28 after suffering from a heart condition.

In a statement shared with ABC News earlier this week, the Panettiere family revealed his passing was caused by a heart condition known as cardiomegaly and complications of the aortic valve.

“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,” they 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.”

“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,” the statement continued. “We sincerely appreciate the outpouring of love and support towards our family as we navigate this unthinkable loss, and ask that we be gifted our privacy during this time of mourning. We love you so much Jansen and you will be in our hearts forever.”

Cardiomegaly, also known as an enlarged heart, isn’t a heart disease in itself but rather an indicator of another condition. According to the Mayo Clinic, the term "cardiomegaly" refers to an enlarged heart seen on any imaging test, such as a chest X-ray. An enlarged heart occurs when the heart has trouble pumping blood efficiently. For this reason, a person with cardiomegaly has an increased risk of heart failure or stroke.

Cardiomegaly can be caused by any condition that makes the heart pump harder than usual, such as coronary artery disease, pregnancy, anemia, cardiomyopathy, heart valve disease, or high blood pressure. Because Panettiere was found to have complications with the aortic valve – which controls the flow of blood from the heart to the rest of the body – this could have possibly affected his enlarged heart condition.

In some cases, symptoms of an enlarged heart may not be present at all, per the Cleveland Clinic. For others, signs of an enlarged heart can often be disguised as other conditions, such as asthma. These symptoms may include shortness of breath, dizziness, irregular heart rhythm, or swelling in the legs, feet or abdomen.

To treat cardiomegaly, doctors must first find what is causing the heart problem. This can be done using a physical exam, tests, or by asking questions about symptoms and family medical history. In addition to a chest X-ray, blood tests, an electrocardiogram, a cardiac CT scan, an exercise stress test, or a heart MRI can confirm or rule out certain conditions that can cause an enlarged heart.

Then, a healthcare provider may prescribe medications to treat the underlying heart condition causing cardiomegaly. If medications aren’t enough to treat an enlarged heart, surgery or medical devices – like a pacemaker – may be needed.

Jansen Panettiere is the younger brother of Nashville star Hayden Panettiere. The 28-year-old followed his older sister’s footsteps when he began his acting career starring in supporting Disney Channel roles alongside his sister.

In addition to his sister Hayden, Jansen is survived by their parents, Lesley Vogel and Skip Panettiere.