Hayden Panettiere's Brother Jansen's Official Cause Of Death Is Devastating

Hayden Panettiere's younger brother Jansen Panettiere died suddenly at the age of 28. Sources previously told TMZ that foul play was not suspected in Jansen's death, though the cause wasn't clear at the time. In an update published by TMZ, the outlet obtained the police report from the investigation and learned that it was Jansen's friends who called 911 after he missed a meeting and no one had heard from him. The report indicates that Jansen was discovered sitting "upright in a chair" though unresponsive, and was rushed to a nearby hospital where he was pronounced dead.

Jansen worked as an actor and an artist and had been fairly active on social media before he died. He often shared some of the artwork he had created on his Instagram account. On February 27, Jansen's family spoke out for the first time since Jansen's death, releasing a statement to ABC News. "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 read. "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," it continued. 

And now, the Panettiere family has also shared Jansen's official cause of death.

The medical examiner was able to determine Jansen Panettiere's cause of death

Jansen Panettiere's officially died due to issues with his heart. "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 in a statement to ABC News. According to the Mayo Clinic, cardiomegaly isn't actually a disease but a condition that is generally caused by something else. One of the most common symptoms of the condition is shortness of breath. And while the Panettiere family didn't offer any specifics when it came to Jansen's aortic valve complications, the Mayo Clinic lists some of these potentially serious medical issues, which include blood clots, stroke, and cardiac arrest resulting in death. 

The Panettiere family was sure to thank the public for their "outpouring" of support during this incredibly challenging time. They have also asked for privacy. "We love you so much Jansen and you will be in our hearts forever," the statement concluded. Jansen will be greatly missed by his family and friends.

Hayden Panettiere & her younger brother were very close

Despite the five-year age gap between Hayden Panettiere and her younger brother Jansen Panettiere, the two were incredibly close. In fact, they would often share photos of the time they spent together on their respective social media accounts. In January, for example, Jansen shared an Instagram photo of his big sis giving him a haircut. And, back in November, Jansen took to Instagram to share a throwback photo of the siblings on a rafting trip. One year prior, Hayden and Jansen took a trip to French Polynesia. "Sibling time at the amaaaaazing market in #Tahiti," she captioned an Instagram pic at the time. 

At the time of this writing, Hayden has not shared any posts about Jansen on social media since he died. Her last Instagram post was uploaded on February 14, and was an ad for the new "Scream" film. Several people have commented on that particular post, offering Hayden their condolences. "I'm so sorry for your loss Hayden! Sending love," one Instagram user wrote. "I am so sorry to hear about your brother's passing.. sending you lots of love," another Instagram comment read.

Jansen Panettiere's girlfriend released a statement following his death

In addition to Jansen Panettiere's family speaking out about his death, his girlfriend of one year, Catherine Michie, a neuro ICU nurse, posted a statement on Instagram. "I will never forget the first time I saw your face and the first things you said to me. Words cannot express the pain of knowing I won't hear your laugh again. I hope you find peace, and I'm sorry I wasn't there when you needed me most. The world is better because you were in it. I know we will paint together again someday. I'll always be your sugarpop. Someone wake me up and tell me this is a dream," she captioned a photo of her and Jansen together, signing it with the sweet nickname that Jansen called her: Bubbles.

Catherine served as inspiration for at least one of Jansen's art pieces. On February 17, just days before his death, Jansen shared a picture of Catherine standing next to what appeared to be an artistic impression of her. Taking a closer look at the Instagram snap, fans can see the word "love" in several places as well as a caduceus, which often represents someone who works in public health services — such as a nurse. Catherine shared the same photo on her Instagram feed with the caption, "two peas in a pod." The photo is also her profile picture on the platform.