A month after his untimely passing, the autopsy of GWAR guitarist Cory Smoot (aka Flattus Maximus) has been completed and released.

The report ( via Metal Insider), from North Dakota coroner William Masselo, MD, reads: "I have determined that Cory died from a coronary artery thrombosis brought about by his pre-existing coronary artery disease."

GWAR Guitarist Cory Smoot, Flattus Maximus, Found Dead

Essentially, Smoot's coronary artery disease, which causes the blood vessels that supply blood and oxygen to the heart to narrow, lead to the formation of a fatal blood clot.

Following Smoot's sudden passing on November 3, GWAR leader Dave Brockie (aka Oderus Urungus) wrote in a statement: "It is with a sense of profound loss and tragedy that the members of GWAR must announce the passing of their long time guitarist and beloved friend Cory Smoot, also known to thousands of metal fans worldwide as Flattus Maximus. Cory was found deceased this morning as the band prepared for a border crossing."

The guitarist joined the Grammy-nominated band in the role of Flattus Maximus in 2002. As for the man behind the red face and dreadlocks, Smoot operated his own music production company/recording studio, Karma Productions, where he mixed, engineered and produced for the likes of GWAR, Skeletonwitch ("Beyond the Permafrost" album) and Municipal Waste.

Born Aug. 25, 1977, Smoot previously played in metal bands Misguided and Locus Factor and continued to play with Mensrea, in addition to establishing his own solo endeavor, the Cory Smoot Experiment.