Physical exercise is good for health in general (1) and especially as a tool in rehabilitation programs for patients with different diseases [e.g., cancer (2), respiratory disease (3), and pain (4)]. In patients with atherosclerotic cardiovascular disease and heart failure, exercise training is associated with a reduction in hospitalization, adverse cardiovascular events, and mortality rates (5–7). Therefore, the European and American Guidelines recommend patients with cardiovascular disease enroll in cardiac exercise rehabilitation (6, 7).

Physical rehabilitation programs can be carried out at hospitals or other healthcare facilities. This clinical practice is excellent because healthcare professionals monitor the patient in person. However, the applicability and extension of rehabilitation programs for most patients who could benefit is limited. Indeed, the development of physical rehabilitation programs at healthcare premises is very expensive in terms of material infrastructure and labor requirements. It is also a problem for patients with time/work constraints or not living near such premises thus requiring expensive and bothering patient displacements. This problem is particularly relevant in rural areas with low-density populations and in underfinanced regions such as low- and medium-income countries (8). Fortunately, developing rehabilitation programs at the patient's home overcomes these limitations and has shown effectiveness in a variety of pathologies, particularly in cardiovascular diseases (9). However, to be effective in terms of patient adherence, a home rehabilitation program requires as much frequent follow-up as possible by health care staff. Whereas such follow-up is difficult to apply through in-person home care visits, it is feasible and useful to use telemedicine tools to facilitate patient-professional interaction (8). Unfortunately, the few applications (Apps) and websites available for home monitoring are proprietary and generic and thus cannot be easily adapted to each specific rehabilitation protocol. The only conventional option would require high development costs entrusted to professional website designers. Therefore, to solve this problem, our work focused on designing and testing a website for the home follow-up of physical rehabilitation for patients with cardiovascular diseases. This telemedicine tool should be characterized by its simplicity for patients and staff, safety by ensuring patient anonymity, open-source availability for any user, and negligible exploitation costs. Our specific twofold aims were first to develop a website that any healthcare professional can download and use as it is. A second and more outreaching objective was to provide a user-friendly Tutorial allowing any healthcare professional without training in website design to customize the website content to any specific application field.

The telemedicine tool we present in this work enables any professional in the field of physical rehabilitation of patients with cardiovascular diseases to immediately and straightforwardly initiate a home care monitoring program by directly using the developed website. Moreover, the Tutorial we propose may allow that, after a minimum training, any healthcare professional without previous experience in website design is able to customize the patient's and healthcare professional's pages for home monitoring in any clinical specialty beyond physical rehabilitation.

We based our telemedicine tool on public internet platforms to avoid requiring the use of proprietary information and communication networks (e.g., from hospitals or other institutions). This enables any healthcare professional to use the website in regions with poorly available Information and Communication Technology provisions from specific institutions, as is common in small or rural healthcare centers or in private practices. The two commercial internet platforms we selected provide the highest data security, processing integrity, privacy, and confidentiality according to most rigorous safety standards (SOC 2 Type 2 certification). Moreover, it is noteworthy that the website was designed to ensure full patient's privacy protection. Indeed, on the one hand, no personal or clinical data related to the patient's health is introduced into the website (only anonymous data on daily exercise). Furthermore, the patient's username and password can be randomly generated by the healthcare professional, hence including no information relative to the patient. Interestingly, the code file linking each patient with their username and password can be kept in a private file curated by the healthcare professional and stored in a physical repository outside the internet and even outside any computer. Therefore, using safe internet platforms and the fact that no patient's personal identification data are introduced into the website offer the highest possible privacy guaranties.

The webpages we designed were deliberately simple to facilitate usability for most patients and healthcare professionals. For instance, each tab in the patient page is contained in a single screen, the labels and windows to introduce data are great enough to enhance visibility for aged patients or those with visual limitations, and colors belong to a blind color friendly palette (12). For the sake of simplicity and flexibility, the data processing and viewing in the healthcare professional page was minimized. Alternatively, allowing the data to be downloaded into a conventional data sheet format makes it possible that any healthcare user involved in the program to further define a specific graphical and statistical processing format. Also, for simplicity we avoided including video calls, with the bidirectional patient-healthcare professional communication based on written messages into the website. If deemed necessary, nowadays a video call can always be established by widespread conventional tools. Interestingly, the website is designed for friendly appearance in both computer, tablet or mobile phone screens. The latter can be particularly useful for open-source initiatives (13) for home monitoring in low- and middle-income countries, where mobile phones are progressively ubiquitous (14).

A remarkable feature of our approach in developing this telemedicine tool was its flexibility to be easily customized for a wide range of applications in home monitoring of patients with different health diseases. As illustrated by the customization section in the Tutorial (a simple possible example for general healthcare follow-up), the website questions and pages layout can be easily modified to cover almost any question that any home came program may need, e.g., on quality of life, patient activities, amount of food ingestion, and physiological variables from home sensors such as hearth rate, blood pressure, weight, glycemia and oxygen saturation. Accordingly, the website could be easily adapted for patient home monitoring in endocrinology, pneumology, sleep disturbances, neurology, psychiatry, postoperative and elder patient care, high-risk pregnancies monitoring, or neonatal follow-up (15–18). It could be also possible to customize the website for professional team-building purposes or for improving coordination among healthcare staff in places without the availability of professional communication networks (19–21). For instance, following the rationale and structure of the website template we present herein, the role of the patients can be replaced by health community workers or small rural/local centers, and reference hospitals can play the role of the health professionals as network coordinators. Accordingly, instead regarding exercise activity, the data interchanged among them could be on a variety of aspects related to clinical practice (e.g., diseases incidence, treatments application, waiting lists or professional inter-consultation), thus allowing to set up an empowering customized network to improve patient's healthcare. Most importantly, with the aid of the Tutorial, such website customization can be carried out by health professionals who are not experts in the construction of webpages, and simply requires internet access, with no need for institutional digital networks availability.

This Methods report describes the design, technical robustness and feasibility of a novel telemedicine approach developed by an interdisciplinary team including health care professionals routinely involved in rehabilitation programs. However, future patient studies should substantiate its performance and outreach in clinical routine.

First, the website developed and presented herein can be of interest for cardiovascular physical rehabilitation professionals aiming at quickly setting up a free tool for home monitoring programs. Second, this telemedicine tool can be customized for different fields of health care applications. Finally, being open-source, low-cost, and not requiring institutional digital infrastructure, this approach can be of particular interest in low-resource settings.