GREENVILLE, N.C.--(BUSINESS WIRE)--Dr. W. Randolph Chitwood, Jr., a globally recognized cardiothoracic surgeon, has performed his 400th robotic-assisted mitral valve repair. Pitt County Memorial Hospital (PCMH), the teaching hospital for the Brody School of Medicine at East Carolina University (ECU), was the site for this landmark cardiac surgery on Friday, June 20. Chitwood has performed more robotic-assisted mitral valve operations than any surgeon in the world.