This episode's headline: News Summary; Housing Bias?; Sullivan Principles: Code of Behavior; Articial Heart Program: Time to Pause?; Joseph Papp, Impresario. The guests include In New York: PHYLLIS SPIRO, Open Housing Center; In Chicago: WILLIAM NORTH, National Association of Realtors; In Louisville: Dr. ALLAN LANSING, Humana Heart Institute; Reports from NewsHour Correspondents. Byline: In New York: ROBERT MacNEIL, Executive Editor; In Washington: JUDY WOODRUFF, Correspondent