It is a challenge to provide an efficient healthcare service for countries with continental dimensions. Mechanisms for a more efficient and better attendance of patients are necessary due to the increasing costs of health care systems. This work proposes the development of a system for monitoring vital signs (including ECG) through PDAs. Therefore, this has made possible the local attendance of patients by medical practitioners (here called health agents) with the support of specialist?s physicians through a second opinion system. The proposed approach supports: recording and visualization of ECG waveforms. Moreover, patient?s information can be transmitted to and from a remote health care server. In order to make easier the use by doctors and health agents, a user-friendly graphical interface has been developed. Methods for an efficient data access have been also developed to cope with storage constraints of PDAs.