Trends portend eventual blend of cardiology PACS, radiology

Radiology PACS and cardiology PACS have more in common than the same last name. Similarities include diagnostic workstations, archive infrastructure, DICOM modality work list functionality, web-based distribution, and interfaces to hospital information systems and electronic medical records.

Radiology PACS and cardiology PACS have more in common than the same last name. Similarities include diagnostic workstations, archive infrastructure, DICOM modality work list functionality, web-based distribution, and interfaces to hospital information systems and electronic medical records.

CardioPACS require the same multimodality, multivendor connectivity capabilities as do radiology PACS. Both deal with large imaging data sets.

"There is a tremendous amount of overlap in the requirements for both PACS," said Dr. Eliot Siegel, director of radiology and associate vice chair for informatics at the Baltimore Veterans Affairs Medical Center.

There the family resemblance ends. Radiology is dominated by modalities that produce static gray-scale images, lending themselves well to the image streaming and window/leveling protocols of radiology. These familiar tools, however, generally do not work with modalities found in cardiology.

"This is not just because cardiology studies are dynamic and often employ color maps, but because they need to be displayed, measured, and quantified in certain clinically established ways not familiar to the radiology world," said J. B. Wang, Ph.D., CTO of Thinking Systems.

CT angiography, for instance, requires special 3D, maximum intensity projection, and multiplanar reformatting tools that conventional gray-scale radiology PACS do not provide.

CardioPACS must possess the ability to perform ventricular ejection fraction measurements, ventricular stroke volume measurements, stenotic indexing of coronary vessels, and wall motion analysis. CardioPACS must also interface with electrophysiology and hemodynamic measurement systems.

Cardiology has also adapted traditional radiologic modalities such as CT for CT angiographic studies. These technologies can incite border skirmishes between radiology and cardiology departments.

"While innovative, these technologies can create turf wars with radiology, since cardiologists are increasingly interested in reading CTA images," said Craig Walker, a partner at VidiStar.

Walker predicts that soon CTA will also replace diagnostic cath procedures, pitting cardiologist against radiologist on an even wider front.

CTA is at the center of an incendiary question"should cardiology or radiology interpret the extracardiac findings produced in these studies?

Most cardiologists feel uncomfortable interpreting extracardiac findings, whereas radiologists, who make their living reading CT studies, feel if they're going to read the extracardiac part, they might as well also read the cardiac part, according to Dr. Paul Chang, a professor of radiology and vice chair of medical informatics at the University of Chicago.Walker predicts that the resolution of this struggle could affect the future of cardiovascular imaging, since most hospitals already have radiology PACS and the outcome of this turf battle may dictate whether a hospital buys cardioPACS.

The Centers for Medicare and Medicaid Services has found itself in the middle of this dispute. CMS recently tabled a decision to suspend reimbursement to cardiologists for CTA reads.

Until that dust settles, a workflow or business model must be established to resolve the issue: Will cardiologists and radiologists read CTA studies asynchronously, or will cardiologists read the cardiac part first before passing the study to radiology for extracardiac interpretation?

If each specialist reads his or her own part, however, that creates two reports. That's one report too many."Clinicians don't want two reports; they want a combined report," Chang said.

The next PACS problem with CTA, then, if only one report is to be produced, is how to create a combined report from cardiology and radiology when both departments typically use different reporting tools. Cardiology uses structured reporting, while radiology still largely employs dictation and speech recognition.

Since no suitable solution exists, researchers at the University of Chicago solved the problem by writing their own work list solution that created two work lists but only one report.

"One work list is for cardiologists to use with their structured reporting tool, and another tells radiologists that here's a study that has already been interpreted by the cardiologist, now add your extracardiac findings using your speech recognition engine," Chang said.


Another workflow issue arises when hospital radiology and cardiology departments have their own PACS but share an imaging modality, such as a CT scanner. A cardiologist who wants access to a CTA study may not have the time or inclination to log on to a different PACS to review the study.

"Providing rules to manage study workflow between two PACS can cause issues for both departments, IT, and clinicians," said James Devlin, vice president of sales and marketing for Digisonics.

While solutions to this quandary tend to be site-specific, one answer lies in DICOM Query/Retrieve, which can pull/push studies from different PACS. Prefetch rules can also be implemented to automatically send images to disparate PACS based on HL7 orders, Devlin said.

Yet another workflow issue involves single cardiology studies that come in sets of images that may be separated by hours, if not days.

"You don't want to schedule that exam as three separate studies, because to interpret it you want it displayed as a single study," Chang said.

Scheduling a cardiology exam may be different from scheduling radiographic procedures. It's not unusual to have cardiology studies requested without an official order passing through a cardiology information system.

"Cardiologists often don't go through the process of requesting the study through a RIS-like system as one would for a consultation from a radiology department," Siegel said.

This issue is compounded by the fact that many cardiology departments don't have RIS-like functionality, although vendors are designing solutions that integrate image and information system functionality.

"For radiology PACS, the RIS provides unambiguous association of the image with the patient demographic, but many cardiology information systems lack that level of granularity," Chang said.

The lack of RIS-like functionality presents two options. Some hospitals skirt the issue by scheduling cardiology exams in the radiology department through the RIS. This seemingly reasonable tactic, however, confounds some billing systems, and it can be regarded as an incursion, escalating tensions between radiologists and cardiologists.

"The idea of cardiology scheduling exams through a radiology information system is anathema in some hospitals," Chang said.

The second option is to develop an in-house cardiology information system. The University of Pittsburgh Medical Center did this during Chang's tenure there.

"We had to build a cardiology information system from scratch just to get cardiology images into our PACS," he said. Later, when Chang moved to the University of Chicago, the same issue existed. This time, however, in his role as vice chair of medical informatics, he opted not to develop another cardiology information system. Instead, he renamed the RIS.

"We now have the Enterprise Image Management System, owned by IT," he said. It may look and behave like a RIS, but radiology no longer owns it.

The term cardioPACS may be a misnomer, in the sense that it doesn't fully describe the range of system functionality."Report generation and image analysis go hand-in-hand with cardiology PACS, so the nomenclature 'PACS' is misleading," said Bryan Schnepf, director of market intelligence and planning in Philips' cardiology informatics division.A relational database of clinical information must be integrated with images so cardiologists can do their job effectively, according to Schnepf. Since cardiovascular disease is progressive, patients need to be monitored the rest of their lives. "This means that powerful logic must be incorporated into cardioPACS to aid in comparative and trending cardiac analysis," he said.

Cardiac reporting is so paramount that a hospital's cardiology purchasing and implementation focus is often more on the use of reporting than on image management and presentation, said Vincent Norlock, senior marketing manager in Agfa's enterprise cardiology sales division.

This slant illustrates a major distinction between radiology PACS and cardioPACS. In contrast to radiologists' typical use of dictation and speech recognition, cardiology has developed standardized structures for clinical reports, measurement nomenclature and electronic data interchange identifiers, and communication protocols that help reduce the user's technical and financial burden.

"With respect to embracing structured reporting, cardiology is significantly more advanced than radiology," Chang said. Cardiology's structured approach to reporting also drives integration of cardioPACs with nonimaging systems, Norlock said.

"In addition to patient and procedural HL7 messages, monitoring, lab, and modality-derived measurements are commonly imported to help in outcomes reporting and results sharing," he said.


The requirement for remote reading and Internet-based online reporting is another developing trend that affects both radiology PACS and cardio-PACS workflow. Cardiologists leaving residencies and fellowships expect predictable work schedules, higher salaries, and convenience. Digital remote reading provides them the ability to read cardiac studies from anywhere.

"For cardiologists, time equals money," Walker said.

Time also equals better healthcare. As the growing number of cardiovascular patients continues to outpace the number of new cardiovascular physicians annually, time will continue to be a major factor in determining quality of care, Devlin said.

"Providing clinicians the ability through cardioPACS to quickly analyze echo images, perform the full suite of echocardiography measurements, and compare these directly with a previous echo exam and associated nuclear and cath studies is no longer a luxury," Devlin said.

Paradoxically, many current cardioPACS tend to operate as individual islands, hoarding images rather than sharing them with the rest of the hospital. Whereas radiologists are expected to share images with the rest of the enterprise, cardiologists tend to collect images for themselves for their own use.

"Cardiologists don't place great emphasis on archiving studies for long periods of time and making them available throughout the enterprise," Siegel said.

Hospital CIOs are increasingly finding that it's impractical to have departmental data silos and information systems that are not necessarily interoperable.

"It becomes a nightmare trying to figure out how to take responsibility for all these different systems with regard to the Health Insurance Portability and Accountability Act and disaster backup," Siegel said.

Even when cardiac studies are made available to the enterprise through web distribution, other issues appear. Enterprise distribution requirements of cardiac studies can be demanding. The complexity of the studies requires that the tools to perform such tasks as volumetric rendering, video, or cine functionality must be provided. Some web clients currently aren't equipped to handle that demand well, according to Chang.

"This is one benefit of leveraging the PACS infrastructure to distribute cardiology images," he said.

From a cardiology perspective, many of the issues surrounding cardioPACS resemble the same ones radiology has been dealing with since PACS first appeared.

"Solutions are expensive and consist mostly of ongoing service contracts, dated software architecture, inconsistent support, lack of flexible reporting tools, and sometimes stressful vendor-client relations," Walker said.

Unfortunately, for most cardiologists, cardioPACS represent just a fraction of the IT tools they need to master to deliver patient care.

"The cognitive load this adds to their work, combined with a relatively small voice in cardioPACS selection, reduces perceived ownership of the system," Norlock said.

In contrast, radiology PACS were likely purchased by the radiologists"the system was theirs."When a physician champion is part of the rollout, acceptance soars," Norlock said.


The cardioPACS market is showing steady growth. Agfa Healthcare has installed more than 500 cardioPACS in North America alone. Still, cardiology imaging solutions lag far behind those found in radiology.

The cardiology landscape has changed dramatically in the past three years, following a series of acquisitions, but some believe all the merger activity may retard rather than accelerate development of new solutions and that acquired units tend to lose their technological aggressiveness.

CardioPACS vendors are currently having the most success in areas in which cardiac imaging traditionally overlaps with radiology. Enterprise-level solutions appeal to heart hospitals where workflow involves considerable radiology imaging services.

"Having separate cardiology and radiology PACS for these institutions is clinically deficient and financially prohibitive," said Sai P. Raya, Ph.D., founder and CEO of ScImage.

Radiology PACS and cardioPACS started out years ago as separate entities."But vendors now understand this is madness," Chang said. "You have to leverage one enterprise archive. No more miniPACS."

Figuring out how to get there from here is proving difficult, however. The problem is what to do with legacy components. The workstations are different in cardiology because the functionality is different. The reporting tools and workflow are also different.

CardioPACS vendors are being pressed to meet new user requirements."Simply keeping up with ever-evolving demands of the cardiovascular market is the number one challenge for all cardioPACS vendors," Devlin said.

Agfa's challenge is to keep pace with customer demand while reducing IT infrastructure redundancy, Norlock said.Previously, cardiology departments isolated modalities like cath, echo, nuclear medicine, ECG, and stress on separate islands, creating an archipelago of infrastructure duplication. The push is swinging around to a department-wide common PACS infrastructure to handle all modalities.

Mr. Page is a contributing editor to Diagnostic Imaging.