Advances in ECG Technology

The resting electrocardiogram (ECG) has been used as a basic cardiac diagnostic for a century, and while the premise remains the same, testing systems are evolving to meet today’s technology demands. This includes increased mobility, ease of use, streamlined workflow and interoperability so data can easily be interfaced with electronic medical records. 

There has been a trend over the past decade toward smaller, more compact, mobile ECG monitoring systems. These can be used either inside a hospital or clinic, or on the road with a visiting nurse or on a cart for mobility between patient rooms. 

Another innovation offered by several vendors includes small box systems that connect via a USB to convert a standard PC or tablet computer into a resting ECG system. 

ECG Automation for Diagnosis and Anatomical Detection 

ECG interpretation algorithms now come standard on many systems. These use gender- and age-specific criteria to provide a virtual second opinion for resting ECG interpretation. This includes ST segment elevation myocardial infarction (STEMI) detection and diagnostic aids to provide interpretation of rhythm and morphology for a variety of patient populations. Some systems include critical values, ST maps and culprit artery identification. 

Some systems have anatomical interfaces to help reduce improper lead placement or detection systems for the presence of a pacemaker.

ECG Workflow Improvements 

ECG systems have been simplified to ease workflow. Examples of this include simplified step-by-step operation, the introduction of touch-screen systems, and better connectivity with ECG management systems, electronic medical records (EMRs) and cardiovascular information systems (CVIS). 

An example of improved workflow can be found in Mortara Instrument’s Eli 280, which combines advanced ECG processing with an intuitive interface and uses a 10-inch tablet-style touch-screen display. It uses an onscreen keyboard feature and dedicated, colored keys for basic operations to streamline use. To improve interoperability, the system uses DICOM for standards-based data exchange with vendor-neutral clinical information systems, and a DICOM modality worklist to retrieve location-specific orders and schedules. 

The interoperability component will become increasingly important, as healthcare reform and Meaningful Use requirements for information technology (IT) systems call for tight integration and easy interoperability to enable paperless healthcare and the free flow of all patient data between departments, hospitals and referring physicians. 

A major roadblock to interoperability has been that older-generation ECG systems were not built using proprietary software and the fact there is no standard format for waveforms. Vendors are now addressing these issues and creating systems with more open IT standards to enable easier integration, even into software systems produced by other vendors. 

GE Healthcare’s Muse has been a popular ECG management system in the U.S. market for years. However, users’ biggest complaint about Muse has been its proprietary software, which prevented or made difficult integration with non-GE ECG systems. In an era of increasing interoperability, GE took this criticism to heart and redesigned Muse to allow plug-and-play, bi-directional integration with most ECG systems on the market. 

GE introduced its redesigned Muse system and Mac 2000 resting ECG system at the American College of Cardiology (ACC) 2014 meeting. Both offer more flexible connectivity options than in past GE systems. Through its i2 ECG Connect interface, Muse now enables integration of ECG data from devices manufactured by Philips, Mortara, Nihon Kohden, Edan and Schiller.

Need to Standardize ECG Formats 

With a major piece of healthcare reform being greater interoperability in health IT systems, data output formats from ECG systems should seriously be considered when selecting new ECG systems. The goal of healthcare reform IT requirements is to improve workflow, ease the transfer of patient data electronically and eliminate the need for paper-based systems, including paper ECG waveforms.

Unlike medical imaging and data that has standardized on DICOM and HL7 formats, there is no standard format for ECG waveforms. The result is an array of file formats for ECGs, including DICOM, XML, TIFF, JPEG, GDT, PDF, ZIP, UNIPRO, DVD and others.  The variety of formats may cause interoperability issues when attempting to save ECGs to a CVIS, or if attempting to data-mine patient information for ECG reports saved as JPEGs.  

The bidirectional transmission options for ECGs also come in a variety of interfaces, including USB, internal modem, GSM/GPRS mobile, LAN or WLAN. Some vendors now offer wireless ECG acquisition, so patients no longer need to be tethered to the ECG system. 

Departments will want to address these format and transmission options with a vendor ahead of installation to ensure the waveforms generated by the ECG systems can be transferred into the cardiology department’s ECG management system and/or CVIS. This data should in turn be easily shared in a usable format with the hospital EMR. 

Partnerships to Expand ECG Interoperability

As interoperability becomes a priority with most healthcare systems, ECG manufacturers have started to partner with ECG management, CVIS and EMR vendors to develop better interoperability. An example of this includes Philips Healthcare and ScImage Inc. creating an integration option between ScImage’s PicomEnterprise CVIS and the Philips PageWriter TC series ECGs. Another is Cerner partnering with Mortara Instrument to introduce CareAware Waveform Management earlier this year. The system displays waveforms and other physiological data from patient monitoring systems and integrates them into the EMR.   

Changes in the ECG Market

A big player in the resting ECG and stress testing market was Cardiac Science. In 2013, Cardiac Science sold its diagnostic cardiology product line to Mortara Instrument, including the Burdick and Quinton brands. 

Remote Access to ECGs

One advantage of paperless ECG review through an electronic ECG management system is the ability to access ECGs and enable remote viewing and reporting outside of the traditional workstation. Most modern CVIS offer remote, anywhere Web-based access to the ECG management system. This functionality includes access to ECGs and fully enabled reporting functions at home or anywhere in the hospital or clinics where a cardiologist finds some time to read cases. 

In addition to improved physician workflow, remote access and mobile device access to dynamic waveforms is a trend to enable faster reads on suspected STEMI cases. Immediate reads on mobile devices can help enable lower door-to-balloon times for heart attack patients with earlier cath lab activation times. 

Wearable and Remote ECG Monitoring

While the traditional 12-lead ECG system will remain a mainstay in cardiac diagnostics in the clinical or hospital setting, the future of cardiac assessment may shift to patients triaging themselves before requiring analysis by these more complex systems. There is a trend in the Holter monitoring and consumer markets toward inexpensive wearable or smartphone-based ECG monitors. Unlike traditional Holter and cardiac event recorders, the new generation of devices are inexpensive or even disposable, and are much easier to use — with the elimination of electrode wires, devices are simply stuck on the patient's chest. Some new devices interface with cell phones to eliminate the need for an external base station hardwired in the patient’s home. 

These devices — combined with consumer-grade, app-based ECG monitors that interface directly with a patient’s smartphone — will likely result in widespread expansion of basic ECG monitoring and represent a novel method for patient engagement in cardiology. IT systems that currently handle ECG management may need to include ways to record data from these types of remotely recorded ECG devices to include it in a patients EMR. This may be required to meet future patient engagement, remote monitoring and other mandated health IT interoperability standards to enable full reimbursement from insurance providers and the Centers for Medicare and Medicaid Services (CMS).

ECG Comparison Chart

This article served as an introduction for the 2016 ECG system comparison chart in DAIC's print magazine. Go to www.dicardiology.com/content/ecg-systems to view the chart.  Access to the chart requires a login, which is free and only takes a moment. The participants are:

Bionet America
www.bionetus.com

Mortara
www.mortara.com 

Nihon Kohden
www.nkusa.com 

Novrav Medical
www.norav.com 

Philips Healthcare
www.medical.philips.com 

Welch Allyn
www.welchallyn.com 

GE Healthcare did not respond to requests for their specifications