William Hamburg has been appointed interim CEO of Cogent Healthcare (Irvine, California), a hospitalist company. Hamburg, who will remain in the role of CEO until the search for a long-term CEO is completed, was president of Surgical Care Affiliates. Most recently, he served as interim chief operating officer of HealthSouth during its 2003 management transition. In addition to Hamburg's appointment, Russell Holman, MD, and Stacy Goldsholl, MD, have recently joined the firm as national medical directors and Tony Redmond as senior director of physician recruitment. Redmond previously was director of recruitment for the Palo Alto Medical Foundation.

Edward Brennan, PhD, has joined CryoCor (San Diego) in the newly created post of chief operating officer. Brennan joins CryoCor with more than 24 years of medical device and venture capital industry experience with such companies as CardioGenesis, DepoMed Systems and Medtronic. Most recently, he was managing director at Perennial Ventures. CryoCor is a development-stage company focused on the treatment of cardiac arrhythmias. Its Cardiac Cryoablation System uses cryoenergy to treat patients with irregular heart rhythms.

Ellen Mahony has been named vice president, client services at MedSynergies (Irving, Texas). In 23 years with EDS, Mahony held a variety of positions, including director of program management and operations and regional technical infrastructure manager. MedSynergies integrates software programs into the daily operations of medical practices.