The development of an implantable haemodynamic monitor (IHM) has made possible the home monitoring of a patient's central haemodynamic trends during daily living. We have evaluated the usability and transmission success of such a system over a 3.2-year period. Patients with an IHM were able to transmit the stored data every week to a Web server, where trend plots and tables of haemodynamic variables could be viewed by the health-care staff concerned. Data transfer was examined from August 2000 to November 2003. During this period, 148 patients had an IHM implanted. Over the study period, 7791 data transmissions were performed and an average of 286 downloads per month were sent to the Web server. In all, 86% of data transmissions were successful, although 10% required more than one attempt. The study demonstrated that telemonitoring of haemodynamic data from an IHM was feasible. A patient survey showed that the technology was user-friendly and that the training material provided sufficient information for patients and their families to install and use the transmission equipment at home. It also suggested that transmission success was independent of patient age or gender.