From Wutan Belgium Blog:
Yesterday we were asked by some people on the exact cause of death of our teacher. So I want to correct any rumors caused by misinformation:
Our teacher Mike Martello died of Wolff-Parkinson White Syndrome, and that morning he woke up and not long after passed away suddenly.
He wasn’t teaching nor training at the moment and the cause of death is sudden heart failure due to a heart condition he was born with. Apart from his heart condition, he was the strongest man I have ever met. We were all sure that he would live over one hundred years old, doing Tai Chi in the park, tossing young strong men around.
He will be missed but also his spirit will remain in our hearts.