Arthur Kananack, longtime entertainment attorney who specialized in legal and theatrical business affairs, died Saturday of a heart attack at Cedars-Sinai Medical Center in Los Angeles. He was 68.A Brooklyn native, Kananack graduated from Cornell U. with a law degree and then served during the Korean War as a 1st lieutenant in the U.S. Army where he was stationed in West Germany. During the 1950s and ’60s, he lived primarily in New York City and London, working for 20th Century fox, CMA and ABC-TV. Beginning in 1972, Kananack spent 10 years based in London as vice president, business affairs – Europe, for Warner Bros. He subsequently was responsible for Warner Bros.’ television distribution for both domestic and international markets. After his return Stateside, he held the post of president of ITC Entertain-ment, where he ran worldwide TV sales and negotiated acquisition/production with HBO. Kananack left ITC after five years and joined Viacom, where he was instrumental in creation of the Intl. Theatrical and Video Sales Dept. as topper of Viacom Pictures. In 1993, he formed Arthur Kan-anack and Associates with his two sons, Michael and Claude. The company, involved in worldwide sales of theatrical and TV product, will continue with his two sons at the helm. In addition to his two sons, Kananack is survived by wife of 40 years, Pamela, a grandson and a sister. Services will be held at 2:30 p.m. today at Forest Lawn, Hollywood Hills, in the Old North Church Burbank. In lieu of flowers, family suggests donations in Kananack’s name be made to a charity of the donor’s choice.