Advertising executive Alvin Guggenheim, whose Houston-based advertising agency worked with numerous studios, died of natural causes Monday at his home in Houston. He was 73.Guggenheim began his career as an usher at a theater in Houston. Following World War II service, he joined Cinema Art Theaters in Houston. He eventually owned and operated 19 theaters throughout the state of Texas. Through the years, Guggenheim was called upon by studios to handle personal appearance tours of celebrities promoting their films. Guggenheim’s advertising agency, which he opened in Houston in 1970, provided studios with a variety of advertising services including local promotions, publicity, print and broadcast placement. Guggenheim is survived by his wife, Hildred, three sons and six grandchildren.