Actor Chris ayres death -What is his death cause?

Chris Ayres is a voice actor. He is known overall for his role as a Frieza in the dragon ball franchise. He passed away on 18 October. At the time of death, he was 56 years old. His girlfriend Krystal LaPorte confirm his death by posting on Twitter.
What is Chris Ayres death cause?
Ayres has had health problem issues over the years. He has undergone a double lung transplant and after being diagnosed with the end-stage chronic obstructive pulmonary disease back in 2017. Ayres is survived by his girlfriend, Krystal LaPorte, as well as his mother and brother.
Chris Ayres Girlfriend Tweet
His Girlfriend tweet his death by sharing 2 photos. Ayres was born in Richmond on May 16, 1965. In 2003, He began his voice acting career. He is getting his start as an extra in the ADV dub of Kino’s Journey. His first voice in anime series over the years.
There are some series such as Saint Seiya, Mezzo DSA, Gantz, Speed Grapher, Fairy Tail, Black Butler, and Panty & Stocking with Garterbelt, among many others.
It is known to all Ayres best known for his role as iconic Dragon Ball villain Frieza. At first, he voiced in the anime series Dragon Ball Z Kai and Dragon Ball Super. He is also known as well as in the anime films Dragon Ball Z. He is also doing other film work named Gintama.
What is Chris Ayres death cause?
Ayres has had health problem issues over the years. He has undergone a double lung transplant and after being diagnosed with the end-stage chronic obstructive pulmonary disease back in 2017. Ayres is survived by his girlfriend, Krystal LaPorte, as well as his mother and brother.