AOL co-founder Steve Case’s start-up, Revolution Health Group (RHG), is expected to launch its consumer Web site RevoltuionHealth.com on April 19. “We are working to build the online destination where you can ‘take action’ to improve your health or your family’s health,” Case said in a statement on the eve of the launch of the site’s preview version in late January. Since launch of the site’s test version, RevolutionHealth.com has assembled an audience of 486,000 unique visitors in March, according to figures from the research firm comScore Media Metrix.