OUP user menu

Remote monitoring as a key innovation in the management of cardiac patients including those with implantable electronic devices

Richard Sutton
DOI: http://dx.doi.org/10.1093/europace/eut108 i3-i5 First published online: 4 June 2013

Abstract

This Introduction to the Supplement provides a brief history of remote monitoring, discusses its current status, and indicates the bright future that it possesses with a broad application in many branches of cardiology, at least including arrhythmias, heart failure, and ischaemic heart disease in addition to the management of implantable electronic devices.

  • Remote monitoring
  • Cardiac implantable electronic devices
  • Quality of life
  • healthcare economics
  • arrhythmias

Remote monitoring

Remote (Home) monitoring of cardiac implantable electronic devices (CIED) represents a major innovation in implantable device technology. However, it is not new. Electronic devices are particularly suited to remote monitoring and the first attempts to achieve this were introduced in the early 1970s in the USA.1 Monitoring was performed by telephone and the data transmitted were basic, pacing rate, and pulse duration. The electronic circuits of pacemakers were designed so that these two parameters would indicate battery status. This had appeal to patients and their physicians especially as sudden device failure was still relatively common and a greater percentage of paced patients were pacemaker dependent. It did not have an impact in Europe mainly because of inadequate telephone technology and political impediments relating to data transfer. Even in the USA, it suffered from lack of or very limited reimbursement for an extended period.

Remote monitoring, as we know it today, was introduced by Biotronik in 2001 and designed to use mobile telephone technology. This ushered in the ability to monitor continuously, both device function and disease trends, a paradigm shift in implantable device technology. It came with a price premium but it was popular and was followed by all the other major manufacturers. These manufacturers use a fixed homebound Internet connection, i.e. not mobile (in contrast to Biotronik's Home Monitoring). All systems process these data, to some extent, before they are delivered to the caring physician.

The introduction of this new technology has been slow based on two facets: lack of reimbursement and fear of data overload on receiving members of hospital or office staff. Both of these facets are now improving because the systems have demonstrated true value to clinicians, most directly illustrated by issues related to device integrity. Notably, the major defibrillator lead problems experienced with Medtronic's Sprint Fidelis lead, which have proved more predictable using the Lead alert system in combination with CareLink.2 Unfortunately, the present problems facing St Jude Medical's Riata lead do not seem so predictable using their Merlin system but the lead faults are different.3 However, in the report of Hauser et al.,4 87% of the leads analysed, albeit at a late stage of disintegration, had shown electrical abnormalities, which may have been detected by remote monitoring.

It can be readily recognized that remote monitoring offers help for over-pressed clinical follow-up departments to be able to manage the huge workload that a manufacturers' advisory causes.

When findings are made on remote monitoring systems, these can be used to avert clinical problems but in their absence nothing can be done.5,6 Another difficulty has been the considerable lack of science in the field. In today's healthcare world, randomized trials demonstrating the clinical efficacy and cost benefit of a new technology are essential. Finally, in the last 2years, some have become available but they focus largely on implantable cardiac defibrillators (ICDs) and have some clear benefits or trends towards benefit of remote monitoring in terms of reduction in inappropriate defibrillator shocks.79

The aspect of reduced workload and cost saving in follow-up departments still lacks convincing data and the old problem of a new technology saving money from the budget of another department requires broad and constructive thinking. In Europe, State Healthcare systems are paying huge amounts to transport patients to and from outpatient facilities merely for routine checking of CIEDs.

It should be easy to demonstrate the cost benefits when a holistic approach is used, since the bulk of routine checks raise nothing requiring action and may be accomplished rapidly and more conveniently by a remote system. These issues have recently been addressed in a thorough study by Cronin et al.10 who have shown overall time saving by using remote monitoring with better focus on findings of clinical importance. However, they did experience a large number of non-compliant patients exposing a problem of manual systems employing technologies that demand patient interaction.11 This has to be overcome by use of automatic data transfer for the widespread use of remote monitoring.

Remote monitoring is of value for all the types of CIED—that is pacemakers, ICDs, and implantable loop recorders. The latter have not been so widely addressed but regular download has been shown to avoid memory saturation with real event loss.12 Remote retrieval and comprehensive archiving permits data analysis of huge numbers of patients to gain understanding of interaction among devices, their programming, and disease as seen in the ALTITUDE study.13 Further, rhythm disturbances can readily be identified in all of these devices allowing early detection of the development of atrial fibrillation. In turn, this permits timely decisions concerning anti-thrombotic or anti-coagulant therapy.14,15

The concern over data overload on follow-up services has been real prompting some data processing by the manufacturers before release to the caring physician. There is scope for increase in this as most follow-up services institute their own processing by nurses or technologists before a physician is involved. That is the physician is in an executive role. There could be a role for centralized processing particularly in a State Healthcare system, which might be expected to make considerable savings.

The technology of CIEDs is such that remote monitoring now must be done and this is the only possible future. Attendance at an outpatient facility for routine checking of an electronic implanted device without resulting clinical action is no longer ‘standard of care’. This facility must in future be used either for clinical care or investigation of faults, real or suspected, detected on remote monitoring constituting a switch to ‘exception-based care’ and increasing its relevance to both patient and clinic.

The future holds great extension of this technique using implantable cardiac monitors that offer parameters of cardiac function in addition to the electronic parameters of device function. Remote long-term monitoring of cardiac function is already practiced but it is a whole new clinical skill that has been difficult to acquire and to prove its value. In clinical medicine we have learnt to assess patients intermittently from the findings on history and physical examination. When seen in comparison with the profusion of data available from remote monitoring, the clinical assessment seems to be a very blunt weapon. However, understanding and discerning real trends from remote monitoring is a new challenge that we must assimilate. So far, we have understood that a single parameter is insufficient for clinical decision-making in heart failure patients and we need multiple parameters, e.g. pulmonary artery diastolic pressure, fluid overload, activity of the patient, and heart rate variability many of which are available today in a single implanted device. Strangely, use of multiple parameter monitoring is exactly what we do when we take a history and make a physical examination. Multi-parameter monitoring should provide early warning of up-coming problems allowing alteration of therapy or diet or both so as to be able to avoid hospitalization in many instances. To achieve this goal we need the right combination of parameters and much more experience of trend discrimination. These comments apply largely to the care of heart failure patients but monitors are being developed today that aim to address many conditions, for example the diagnosis of acute myocardial infarction.16,17 Again, this is currently a single parameter, which will probably prove inadequate but thought should be given to including chemical parameters in implantable cardiac monitors to make the parameter combination more specific for the problem in question. This is expected to position the physician of the future to be able to intervene preemptively to avoid an anticipated crisis rather than merely treating one that has already presented as a clinical problem.

The future in cardiology is remote monitoring, potentially of all types of cardiac patient, which will come to be regarded as so important as to be on a level with, for example, dual-chamber pacing, lithium batteries, active can defibrillation, and cardiac resynchronization therapy in the evolution of the technology of implantable devices.

Conflict of interest: none declared.

References

View Abstract