Rock guitarist Dick Wagner, whose prolific session work graced the albums of such acts as Alice Cooper, Lou Reed, Kiss and Aerosmith during the 1970s, has died at age 71 in Arizona, his manager said on Thursday. The Michigan-bred musician, featured on scores of albums and hailed by fans as "the Maestro of Rock," suffered from a number of health problems in his later years, including two heart attacks and a stroke. He died on Wednesday at a hospital in Scottsdale, Arizona, succumbing to respiratory failure about two weeks after undergoing a cardiac procedure, his manager and business partner, Susan Michelson, told Reuters. Wagner began his rock career in the 1960s with the formation of an early Detroit-area band called the Bossmen. He gained wider notice after establishing the Frost, recording his first three Billboard-charted albums with that group. After moving to New York he formed another band, Ursa Major, whose original but short-lived lineup included Billy Joel on