Echocardiography

Telemedicine has become the standard of care in pediatric echocardiography. Tele-echocardiography can be carried out via live videoconference in real time or as store-and-forward images to be viewed remotely. Initial telemedicine studies utilized point-to-point Integrated Services Digital Network (ISDN) and Terrestrial-1 connections for live telemedicine with good image quality and acceptable temporal resolution (frame rates of 23 to 30/second). Rapid progression of technology over the last 10 years has made this technology obsolete. Today, Internet Protocol (IP) allows for multipoint network connectivity that enables use of codecs or videoconferencing software from anywhere on any device. These include room systems, desktop or laptop computers, tablets, and smart phones.

The field of pediatric tele-echocardiography has predominantly evolved into store-and-forward solutions that, in many cases, are extensions of existing echocardiography picture archiving and communication systems (PACs) with special considerations for data transfer. Direct point-to-point study transmission options include secure file transfer protocol (FTP) and virtual private network (VPN). Cloud servers enable transmission of and access to echocardiograms from anywhere in the world with subsequent download into local PACs servers. Many physicians access echocardiograms via remote connection to PACs networks through client or web-based programs. In our hospitals, we have a mix of all of these technologies, but we prefer that studies be transferred into our PACs system for uniform interpretation and reporting. However, some partner hospitals insist on us reporting in their local PACs and electronic medical records. Diligent attention to security, licensure, and credentialing requirements, and compliance issues as well as a need for 24/7 technical support staff are critical for maintenance of a successful tele-echocardiography network.

Multiple studies have found neonatal tele-echocardiography to be accurate and cost-effective, have a positive impact on patient care, prevent unnecessary transports, and improve sonographer proficiency. Table 91.1 , modified from a recent scientific statement from the American Heart Association, provides a summary of several of these studies. When not diagnosed prenatally, newborns with congenital heart disease are often delivered, or present to a primary care setting, where expert cardiovascular evaluation may not be available. Management decisions based on incomplete or delayed diagnostic information may result in morbidity and mortality or unnecessary transfers. Randolph et al. reported that using telemedicine resulted in a complete diagnosis for 132 of 133 patients (99%) with suspected congenital heart disease. Patient transfer was recommended or avoided in seven patients, an immediate change in local medical management occurred in an additional 25 of 133 neonatal patients (19%), and congenital heart disease not requiring immediate treatment was noted in 47 infants (35%).

Rendina et al. reported a reduction in length of stay of 5.4 days in a level III North Carolina neonatal intensive care unit in the first 6 months of their study compared to the 6 months prior without telemedicine. The cost attributable to telemedicine in their model was $33 per echocardiogram. They projected that cost savings over a 1-year period would be $1.3 million. Additional monetary benefits of telemedicine that are more difficult to quantify include cost savings from prevention of delayed or incorrect management, and avoidance of the financial burden of travel and lost wages for the patient’s family. In a study of 500 echocardiograms in the Washington, DC, metro area, comparison of final videotape interpretation to initial telemedicine diagnosis resulted in only one minor diagnostic change (membranous vs. inlet ventricular septal defect), and telemedicine had an immediate impact on patient care in 151 studies.

We reported on our technology transition experience of over 10,000 telemedicine transmissions from 24 sites in seven states and territories between 1998 and 2014. A significant increase in telecardiology utilization took place after IP expansion without detrimental effects on efficiency or diagnostic accuracy. This occurred in parallel to a change from a predominance of real-time telemedicine to store and forward transmissions. Over 150 patients were transported for surgical, catheter-based, or medical intervention, and critical heart disease was ruled out in over 75 patients, preventing unnecessary transport. Medical management and/or outpatient follow-up was recommended in approximately half of the studies for minor heart defects.

A multicenter study from nine centers assessed the impact of telemedicine on infants with either no or minor heart disease. The authors identified 338 pairs of infants with and without access to telemedicine, and were matched for study indication, diagnosis, gestational age, birth weight, and gender. Access to telemedicine resulted in statistically significant reductions in rate of transfer to a tertiary care hospital (10% vs. 5%), total and intensive care unit length of stay, and inappropriate use of inotropic support and indomethacin ( Tables 91.2 and 91.3 ).

Neonatal pulse oximetry screening for critical congenital heart disease is currently mandated in almost every state and is a driver for the establishment of telemedicine links between community hospitals and tertiary care pediatric cardiac centers. Telemedicine can provide timely access to pediatric subspecialists in cardiology and neonatology for assessment and treatment recommendations if a positive screen is obtained. There is an argument that false-positive pulse oximetry screens could increase the number of tele-echocardiograms, pushing up costs and overburdening pediatric cardiologists providing interpretation. However, a recent study shows that the additional increase in echocardiograms from pulse oximetry screening is negligible when compared to the number of false-positive echocardiograms generated by heart murmurs.

Fetal Telemedicine

Fetal telemedicine can increase prenatal detection of critical congenital heart disease. Sharma et al. reported that adequate screening for fetal heart disease is feasible and community acceptance for telemedicine-assisted fetal cardiac screening and counseling is not adversely affected by a lack of direct personal contact with a specialist. Prenatal detection of congenital heart disease has been shown to improve postnatal surgical and heart transplantation outcomes. Fetal telemedicine is also used across all links of the referral chain, from the primary obstetrician’s office to the quaternary fetal health care facility. It is routinely performed by obstetricians, maternal-fetal medicine specialists, and pediatric cardiologists to screen for congenital heart disease and fetal arrhythmias. If pathology is suspected or detected, these providers can refer patients to a higher level of care. Because access to fetal cardiac expertise is limited for people in remote or rural locations, fetal tele-echocardiography can be especially helpful in these populations. The use of fetal ultrasound to detect congenital heart disease can also help pediatric cardiologists and maternal-fetal medicine specialists work together to prepare families for delivery and treatment options.

Fetal telemedicine can also be diagnostic for fetal arrhythmias. In the case of fetal bradycardia secondary to atrioventricular block, tertiary care fetal health centers can use fetal telemedicine to guide and monitor pharmacotherapy and delivery planning, which is paramount for patients that are likely to need an urgent pacemaker after birth. Fetal telemedicine can also play an important role in diagnosing and treating fetal tachycardia. Transplacental or direct fetal antiarrhythmia treatment, follow-up evaluations, and delivery plans can be appropriately determined upon review of the images. There are currently commercial and FDA-approved hand-held Doppler fetal heart rate monitors available for patient home use. Prospective parents can purchase them at low cost on the Internet. These devices hold promise, especially if they have Bluetooth or network connectivity. However, more data is needed to assess the utility of these devices for future home monitoring, The importance of physician input is critical, as inappropriate use of home monitoring can do more harm than good.

Intensive Care Unit/Cardiac Intensive Care Unit

Telemedicine has many applications in the pediatric intensive care unit, cardiac intensive care unit, and emergency department, using a broad range of applications to assist in the care of hospitalized children in a variety of clinical scenarios. There is increasing acceptance and evidence that providing pediatric critical care and telecardiology consultations to remote emergency departments for children with suspected or known cardiovascular disease is feasible and adds clinical value. Telemedicine can be used in an on-demand or continuous model for support of critical care patients. In the former model, physician consultations, nurse and physician monitoring, and medical oversight can be provided on an as-needed basis. A pediatric cardiologist or intensivist can evaluate and provide recommendations on diagnostic studies, medications, or other therapies. The other end of the spectrum integrates continuous oversight via monitoring and proactive medical decision making. All models require compliance with best critical care practices and maintenance of training, including advanced life support certifications and participation in quality assurance programs.

Use of telemedicine in a variety of critical care programs around the globe have demonstrated improvements in clinical outcomes, including length of stay and mortality and increased provider and parent satisfaction. Reductions in healthcare costs occur due to more appropriate transport utilization and decreased utilization of costlier tertiary intensive care unit beds. Patients in critical care settings with access to telemedicine can be more quickly evaluated, stabilized, and triaged to determine the need for transport and more advanced treatment. Munoz et al. reported on a telemedicine-supported cardiac intensive care unit collaboration between Pittsburgh and Bogota, Columbia. This program included a web interface of physiologic monitors and videoconferencing via a mobile telemedicine cart. Face-to-face videoconferencing, sharing of medical images, and review of rhythm disturbances resulted in 71 recommendations in 53 patients including management of arrhythmias and surgical and catheterization planning.

Outpatient Telecardiology

Several groups have reported improved access and quality with reduced costs for both adult and pediatric cardiology outpatient evaluations. Such systems aim to replicate the classic consultation for remote providers, thereby extending the reach of the specialist into underserved areas. Most of these programs are focused on history and test (electrocardiogram [ECG] and echocardiogram) review. These programs reduce the need for face-to-face evaluations but can increase the overall number of contacts with the specialist, likely due to ready specialist access for primary care providers. One Spanish synchronous provider-to-provider consultation with multimedia support had similar success where only 10% of patients undergoing teleconsultation required travel to the tertiary-care facility.

In Canada, synchronous teleconsultation has been useful for remote preprocedural counseling as well as evaluation of new patients with syncope and supraventricular tachycardia. In the United Kingdom, a broad range of both inpatient and outpatient telecardiology services are available to the district hospitals, utilizing various technologies. Their approach improved access, was cost neutral, and was appreciated by patients. The authors stressed that this approach supplemented, but would not replace, regularly scheduled outreach clinics. Successful sites had dedicated clinical champions and were designed by local clinicians to meet their specific needs. Failing to recognize these requirements has caused others to fail.

Tele-auscultation can also be a part of remote consultation, but is not used as frequently as other modalities, in part due to cost and reimbursement issues. Over the last 2 decades, several investigators have evaluated different hardware and software solutions for remote murmur evaluation. Belmont and colleagues utilized the synchronous approach using both digital and analog systems. They found significant differences in heart sound characterization when compared to face-to-face evaluation by a pediatric cardiologist using an analog stethoscope. However, when used to classify overall findings as either normal/innocent versus pathologic, their tele-auscultation was no different than face-to-face evaluation.

McConnell et al. also utilized a synchronous tele-auscultation approach with similar accuracy.

Other investigators have focused on the asynchronous (store-and-forward) tele-auscultation approach; that is, to have heart sounds recorded at the patient site for transmission to the remote cardiologist for later review. These studies have combined a variety of digital recording stethoscopes with electronic transmission via e-mail or a web-based platform. Overall accuracy was similar to face-to-face evaluation.

Digitally recorded heart sounds also provide the opportunity for computerized analysis of this physiologic data, referred to as computer-aided auscultation (CAA), and could be incorporated into an asynchronous tele-auscultation program. Several groups have applied a variety of signal processing techniques to pediatric heart sound recordings and report sensitivity and specificity values approaching 100%. Despite the potential, CAA has not yet been widely adopted despite at least one FDA-approved system currently available. As with tele-auscultation, this is likely due to a combination of technical, practical, and financial disincentives.

Direct to Consumer Telemedicine

The marketing of and demand for “direct to consumer” medical care in the home via web-based applications that include tablet and smart phone applications is growing rapidly. Many insurance providers and large employee health plans are adopting this technology as a way to provide lower cost care for common problems that might otherwise result in an emergency room visit. Direct to consumer telemedicine primarily relies on video and audio connections between physician (or other health care providers) and the patient. The tablet, smart phone, or computer-based application may include additional features that allow for scheduling, billing, sharing of still-frame images, and documentation. In some models, peripherals may be available such as smartphones, compatible heart rhythm detection devices, and otoscopes. In our program, we are utilizing our own physicians to provide this service for follow-up visits for syncope, preventive cardiology (obesity and hypercholesterolemia), neurodevelopmental assessment, and transplant/chronic heart failure.

The most common model for direct to consumer telemedicine is a one of a turn-key service that includes access to technology and a physician group provided through the same vendor that provides the technology. This could, in theory, create a threat to the delivery of high quality care, especially for complex pediatric patients. Additionally, as the use of these devices grows, careful attention must be paid to patient safety and privacy. In response to this concern the American Telemedicine Association has implemented an Accreditation Program for the provision of consumer-directed telehealth services.

Electrophysiology

Telemedicine has been used for years for simple transmission of electrophysiologic data through transtelephonic event recorders and pacemaker evaluations. Remote monitoring of rhythm data from bedside monitors is also commonplace. Leveraging applications for smart phones and tablets for rhythm analysis makes monitoring of cardiac electrical activity detection of arrhythmias and myocardial infarction feasible. The SEARCH-AF trial from Australia evaluated nearly 1000 patients with a single-lead ECG device built into an iPhone case. The technology was accurate and cost effective and has the potential to prevent stroke. A modification of the existing single-lead device was used in a recent study for assessment of ST elevation myocardial infarction (STEMI). There was agreement in six patients (four with STEMI and two with non-STEMI) when comparing the smart phone tracing to 12-lead ECG. This technology can generate tracings of diagnostic quality in children with positive user satisfaction and could be used to manage children with supraventricular tachycardia and atrial fibrillation. New “biomedical shirt” technology that enables even more practical remote ECG monitoring for children and adults is currently under investigation.

Take the example of J.K., who is a savvy teenager with a history of intermittent palpitations. He has recently started to use a wearable device to track his heart rate and rhythm in addition to an event monitor prescribed by his cardiologist for suspected pathologic tachycardia. While watching a video on his cell-phone, suddenly he feels a pounding sensation in his chest. Using his new cell-phone technology he notices that his heart rate is 180 beats/min. He informs his mom, who starts driving him to the nearest emergency department 10 minutes away. On the way, he transfers his heart rate information to his cardiologist office, which gives the local emergency room a heads-up. In the emergency department, he is quickly triaged and connected to a cardiorespiratory monitor and confirmed to be in supraventricular tachycardia. A peripheral intravenous catheter is started while vagal maneuvers are attempted. In the next minute a bolus of adenosine converts him back to normal sinus rhythm with a heart rate of 70 beats/min, bringing relief to the patient and his mother.

While the details of the above event were slightly different in real life, smartphone- and smartwatch-based tele heart rhythm monitoring is on the rise and is predicted to soon be ubiquitous.

Mobile device–mediated telemedicine is likely to transform direct-to-consumer telemedicine. Kardia Mobile by Alivecor is a medical device for home telemonitoring that is Food and Drug Administration cleared and has received European Conformity marking, indicating it conforms with health, safety, and environmental protection standards for products sold within the European Economic Area. Kardia uses a single-lead ECG tracing that is acquired for 30 seconds with placement of two fingers from each hand on the device electrodes. The ECG recordings are transmitted to a compatible device running Google android or Apple iOS mobile operating systems. It has been clinically validated for the recording of single-channel lead I ECGs in clinical and community-based trials. At the Heart Rhythm Society 2016 scientific sessions, Begg and colleagues presented a comparative study of AliveCor monitor and found it to be superior to conventional Holter monitoring in patients with palpitations, providing a higher diagnostic yield, more detected arrhythmias, with a similar workload. Using mobile telemedicine devices enables prompt ECG confirmation/exclusion of a probable arrhythmic cause of symptoms, enabling rapid intervention for cardiac-relevant complaints. AliveCor monitoring has the potential to enhance evaluation of symptomatic college athletes by allowing trainers and team physicians to make diagnosis in real time. Events of life-threatening wide-complex tachycardia have been reportedly recorded by patients and complete heart block by bystanders using this technology. This has the potential of being more widely available and accessible than defibrillators in public places. Halcox and colleagues showed that telemedicine screening with twice-weekly single-lead iECG in ambulatory patients aged 65 years or older at increased risk of stroke is significantly more likely to identify incident atrial fibrillation than routine care over a 12-month period.

There are randomized clinical trials underway to investigate the utility of a mobile telemedicine intervention in a “real world” setting. Participants are being randomized 1 : 1 to receive the iHEART intervention, receiving an iPhone equipped with an AliveCor mobile ECG and accompanying Kardia application and behavioral altering motivational text messages or usual cardiac care for 6 months. In the adult population, postablation of arrhythmias, monitoring using a mobile-based platform, is preferable compared to traditional telemedicine monitoring. In the increasing technology savvy pediatric population and the young parents, one can imagine more widespread acceptance of cell-phone–based telemedicine portal. There is FDA approval for using mobile ECG monitor: Kardia and Kardia Mobile for adult patients.

Medical providers are embracing mobile-based diagnostic tools. Lesham-Rubinow and colleagues set up a telemedicine call center where transmitted three-lead ECG recordings were instantly displayed on a monitor for immediate diagnosis by the on-duty medical team. Telemedicine allows transmission of cardiac recordings by cellular communication at the push of a button. Users can concomitantly relay symptoms by cellphone, thereby providing a symptom/cardio rhythm correlation. Their set-up allowed for prompt response to abnormal tracings, especially when accompanied by symptoms selected from the prepared list. It enabled their staff to instruct the subscriber, notify their physician, and/or dispatch a mobile intensive care unit to the scene in a matter of minutes.

Photoplethysmography (PPG), is an optical method available on a smartphone or tablet, for consumer-based telemedicine, without any additional peripheral devices like Kardia. It measures changes in tissue blood volume caused by the pulse. A PPG waveform is acquired from a finger illuminated by LED smartphone flash and while that finger is also in contact with the phone camera. A software application (Cardiio Rhythm) then measures pulsatile changes in light intensity reflected and classifies rhythm as “regular” or “irregular.” While the sensitivity and specificity of optical PPG is less than ECG-based detection, it is also quite high. On Apple’s App store and Google’s Play store, applications such as “iCare Health Monitor,” “Cardiograph,” “Heart Rate Monitor,” and a few others that use PPG for heart-rate measurement have had millions of downloads.

Wrist-wearable devices like smartwatches are less well validated than smartphone-based devices, but that is likely related to the fact that they are newer technologies. Wang and colleagues evaluated four wrist-worn, optically based heart-rate monitors and found that two of the four had suboptimal accuracy during exercise. Health care teams are working with device manufacturers to improve their precision and accuracy. There have been anecdotal case reports of the Apple Watch used for continuous heart-rate monitoring in premature infants. However, at this point these wearable smartwatches are primarily helpful in setting safe and appropriate fitness goals, counseling on other lifestyle changes, and providing overall feedback and encouragement. In their recent commentary published in Canadian Medical Association Journal, Khan and colleagues recommend that physicians should still confirm resting heart rates with medical-grade equipment. But they do appear to be supportive of the notion of wearable technology by saying that by use of wearable device–based telemedicine, the wearer takes a voluntary step toward improving his or her health.