A special computer network has been specifically designed and realized to connect 36 Italian cardiological institutions to a central core laboratory. This network, which has been created to run the CEDIM Multicenter Trial (effects of L-carnitine on left ventricular function in patients with myocardial infarction assessed by digital echocardiography), enables automatic verification, via computer, 24 hours a day, of patient eligibility criteria, randomization, transmission, and filing of real-time left ventricular echocardiographic examinations. All the investigators participating in the CEDIM trial underwent several training courses as well as dummy run procedures to achieve optimal performance of all the operational procedures required for the network to function smoothly and correctly. This paper describes the aims of this special network, its technical characteristics, and the investigator training and dummy run procedures.