Funeral arrangements are pending for Louisville artist Stephen Irwin, who was found dead Monday.The Courier-Journal reports that the 51 year old Irwin was found unresponsive by fellow artist and friend Chris Radtke Monday morning at Zephyr Gallery on East Market Street.The cause of death has not been determined. Colleagues say Irwin had a history of heart problems. Irwin was a former visual designer for the old Ben Snyder's department store and later co-owned a downtown nightclub called Sparks.His art has been exhibited in galleries around the world. He was a member of Louisville's Zephyr Gallery artists collective.