Dee Snider is placing the blame for A.J. Pero's death squarely at his late bandmate's doorstep. The Twisted Sister frontman says Pero should have had himself "checked out" for cardiovascular disease, which runs in the drummer's family, and angrily calls his failure to do so "irresponsible behavior."

Pero died of a heart attack on March 20. He left no written will, resulting in a complicated tangle of legal issues those who remain. Snider, meanwhile, has been enduring a complicated range of emotions.

"People ask me how I feel about A.J.'s passing, and, quite honestly, I'm going through a real period of anger right now about it," Snider tells TMZ. "He was a great guy, and I loved him dearly. But he had a history of heart disease — his family did; his father died in his early 60s of heart disease — and A.J. never had himself checked out."

Pero had two ex-wives, a long-time girlfriend, and four children between the three women, Snider notes. Twisted Sister have since announced a final, 40th anniversary tour, which will include a benefit show to assist Pero's family.

Snider says it shouldn't have turned out this way. "When they did the autopsy, he had 95 percent blockage, advanced heart disease – and he didn't have to die," Snider adds. "And I feel it's, basically, irresponsible behavior on his part. You have a responsibility, as a parent, as an adult, to get yourself checked out."

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