With the continuous growth of computer networks in hospitals and, more importantly, the possibilities for contacting other hospitals and healthcare providers by high-speed internet, plus the demand for faster diagnosis and cost-reductions, the interest for tele-medicine is increasing. The definition of tele-cardiology is: “the use of cardiovascular information exchanged from one site to another via electronic communications improving healthcare and education of the patient regardless of geographic or socio-economic status”. Some possible reasons to perform tele-medicine are to:
- improve efficiency, bring the problem to the physician, instead of the physician to the patient (intra- and inter-hospital);
- save valuable time in case of emergencies;
- reduce costs; and
- have global access to healthcare and healthcare information (e.g. teaching).
Willhelm Einthoven (1860–1927) performed the first remote consultation in the field of cardiology, by telephone, at the beginning of the past century, in 1905. Since then it has taken a long time before we were able to transmit measured cardiovascular parameters, such as electrocardiograms (ECG), other than to discuss the status of the patient verbally. The ability to transmit a patient’s ECG is a good example of the benefits tele-cardiology can bring and it has impacted greatly on the treatment of acute heart attacks. For example, ambulance staff can perform and transmit ECGs to remote cardiologists who can diagnose and direct staff to start immediate reperfusion treatment intravenously. This has proven to be a life- and time-saving treatment option that prevents further myocardial damage and improves the quality of life for the patient, when compared with diagnosis and treatment being delayed until the patient arrives at hospital.1,2
Today we can communicate by mobile telephone, wireless connections, computer networks and the internet. The on-going digitisation of medical data and equipment, which previously recorded analog data by video-tape and paper, and their miniaturisation, are driving the demand for instant access to patient information. The data we would like to see are vital signs, laboratory results and current status, as well as the results of imaging procedures. For a long time the words ‘tele’ and ‘remote’ related to absolute distance, or sites that could only be reached after long travel times (e.g. rural areas or even in space). For example the international space station orbiting the earth has an ultrasound device on board.3–6 Such projects show the value of long-distance consultations, guidance or even remote-controlled examinations and, today, the presence of ultrasound equipment on international space stations no longer sounds exotic. Tests can now be performed remotely, as if a patient were on the planet Mars,3,4,7 and this outmoded ‘tele-‘ paradigm has shifted. Many hard-to-reach locations can be better contacted by electronic means, cutting travel time and increasing time spent on expert consultation.8 Also, many large facilities are often an assembly of many individual buildings, which can result in lost time travelling between buildings. As most hospitals have computer networks and clinicians are acquainted with technology, such as teleconferencing, more contact to other locations can be made in this way.
Getting access to a patient’s electronic record (text only) is not technically difficult. Transmitting a patient’s ECG, while the patient is off-site, is more technically challenging but the method has been available since the mid 1980s. Previous difficulties included transmitting image data and, in particular, cardiac image data, as the heart is a dynamic organ and high image quality is required for a proper diagnosis. Large amounts of data need to be transmitted but this is only possible by applying image compression, which can cause a deterioration of the quality.9 In the early days of tele-echocardiography the images of the analogue ultrasound console were digitised by computer first, applying so-called frame-grabbers, and were than compressed before transmission, to avoid transmit times of several hours and reducing the need to send images overnight. The images were then stored locally and forwarded to the remote site where they were stored again before viewing and discussion.10 Most of these projects were in-house developments and could not be used on a larger scale.
However, technological development fuelled by consumer demands for high-definition television and movies, have become available and can also be applied to tele-echocardiography. Together with several key developments within echocardiography itself, this is now accelerating the specific demand for tele-echocardiography.
- A miniaturised echo device was proposed long ago11 but only during the last decade, owing to the continuous improvement of the processing power of computer chips, has it become possible to develop handheld echocardiographic devices on a large scale. These portable devices can be used inside or outside the hospital.
- There is less dependence on hard-wired telephone connections. Broadband computer networks (wired by ethernet or wirelessly by WIFI) are standard in most hospitals and broadband internet access is increasing, making it much easier to connect to the internet and to other computer networks.
- There is a growing use (especially among the new generation of cardiologists) of smartphones and/or laptops. It is becoming impossible to work productively without continuous internet access.
- Digital storage of image data on so-called picture archiving computer systems (PACS) and the standardisation of medical images (the so-called DICOM standard) are becoming commonplace, as well as full electronic patient records.12–14
It will soon be possible to perform tele-echocardiography ‘online’ and in ‘real-time’, maintaining the highest image quality and without having to develop and apply in-house tools. In other words we will be able to connect (e.g. by inserting a network cable only) to these components to our computer networks without trouble. However, there are still challenges, such as the implementation of the DICOM medical image standard for echocardiography, which is not always implemented similarly by the various ultrasound manufacturers.13 Compatibility issues, between software and equipment produced by different manufacturers, can cause problems when viewing anything other than the simplest echocardiographic data. Specific ‘extra’ measurement functionality (quantitative analysis) is sometimes hard to access as it is stored in so-called private-tags in DICOM data, but can only be accessed by that specific manufacturer’s software.
Therefore, patients who are transferred to a tertiary hospital may undergo duplicate examinations, because of such interfacing problems. Besides these technological problems, which could and should be solved, we are facing other problems that need to be addressed before tele-echocardiography can be incorporated into daily clinical practice. Some of these problems are:
- training; and
- attitude and acceptance.
These problems need the attention of all those involved in medical practice, e.g. physicians, hospital management, manufacturers, insurance companies, national and international societies, such as the European Society of Cardiology (ESC) and the American Society of Cardiology (ACC), who could play a role in bringing everyone together and defining the necessary training programs. As with most new technologies, the big question is when to start to implement this into practise. New technology comes to the market almost daily and the options are overwhelming. Questions that should be asked include: is the technology now mature, will it do everything I need, is it future proof and can we upgrade if necessary and most importantly will it integrate seamlessly with our existing technology infrastructure? Also, can we add it to our computer network without further developments that we have to develop locally, can the images be stored onto the PACS we already have installed and can we perform all the quantitative analysis we need? Those questions are not easy to address and it is here where clinicians must work with sonographers, medical IT experts and hospital physicists to ensure that a new system does not become a ‘stand-alone’ entity, being unsuitable for tele-applications.
Despite these concerns, the future looks bright for tele-applications as it seems inevitable that the technology will eventually integrate and become available as an extra function within ultrasound consoles. Recently, smartphone and tablet computer devices, which could drive the demand for tele-echocardiography even more strongly in the short term, have become commercially available. These devices can connect to both wireless computer networks as well as to wireless telephone networks, enabling independent access to patient data wherever you are. Quality wise, such devices, for example the Ipad™ from Apple, have screens that outperform most of the standard outpatient clinic computer monitors; recently one radiologic visualisation application received clearance from the Canadian health authorities to be used to perform diagnosis. Unfortunately, today there is no DICOM viewer yet available, capable of showing dynamic cardiac information such as echocardiographic examinations, but it is a matter of time until these capabilities are made available on such portable devices. In conclusion, it is not a question anymore ‘if’ tele-echocardiography will become an integrated part of our clinical available echocardiographic tool set, but ‘when’.