Cardiology PACS basics: The Integrating the Healthcare Enterprise initiative

Dr. Jonathan Elion is a cardiologist, computer scientist, and cofounder and chief medical officer of Heartlab, a company that develops systems for the digital management of cardiology reports and data sets. The former director of the cardiac image processing laboratory at the University of Kentucky, he has been involved in cardiac image processing since 1983.

Elion has had hands-on experience with electronic medical records, integration, HL7, and other technologies related to modern hospital information systems. He maintains an active practice in cardiology and is a fellow of the American College of Cardiology.

In an interview in February, Elion answered Diagnostic Imaging's questions about the role of the Integrating the Healthcare Enterprise initiative in cardiology.

Q: What is the Integrating the Healthcare Enterprise initiative?

The IHE initiative began in November 1998 as a collaboration between the Healthcare Information and Management Systems Society and the RSNA. Its goals are to improve the ways that hospital computer systems share information. IHE has expanded beyond radiology and now includes information technology infrastructure, laboratory, and cardiology. It defines a framework for information sharing and uses existing standards such as HL7 and DICOM to address specific clinical needs.

Q: Describe your work on behalf of the IHE.

I have been active on both the planning and technical committees for cardiology. The planning committee brings together cardiologists, vendor representatives, and staff from the professional societies to identify common integration problems and issues related to accessing information and clinical workflow. I have been serving as the cochair of the technical committee for cardiology, where the clinical requirements set forth by the planning committee are translated into detailed specifications to make it happen.

Q: Why is the IHE important for cardiology?

"Why do I have to enter the patient's information into so many different systems in the cardiac catheterization lab?!" "Why can't I send the echo report to our hospital information system?" "Why can't I access my patient's electrocardiogram from anywhere in the hospital?" These are common complaints even in hospitals with the most sophisticated computing environments. IHE provides the framework to address these and other related problems. Cardiology information systems (CIS) now manage more than just images and no longer can be seen as isolated departmental systems. There is a need for integration of the CIS into the entire hospital information architecture, and IHE provides the framework to accomplish that.

Q: What is the history of cardiology's participation in the IHE? What other groups are participating?

This year marks a huge step forward in IHE, as we address issues of information integration related to the cardiology department. This step began at the end of 2003 and has seen a vast effort by our planning and technical committees throughout 2004. Many professional societies are participating, led by the American College of Cardiology, the American Society of Echocardiography, the American Society of Nuclear Cardiology, the Society for Cardiovascular Angiography and Interventions, and the European Society of Cardiology.

Q: In what ways has cardiology already benefited from participation in the IHE?

Although cardiology shares many issues with radiology when it comes to managing orders, demographics, and results, many aspects of cardiac studies have not previously been fully addressed by IHE. While CT scans and chest x-rays each constitute a single imaging modality, the cardiac catheterization laboratory is inherently multimodal and presents new challenges for integration.

X-ray angiography, hemodynamic monitoring, intravascular ultrasound, and clinical documentation systems must all synchronize on the same patient information. Emergency cases are common, and often an order that would otherwise serve as the synchronizing event has not yet been created. Echocardiography presents the challenge of managing workflow with a device that is intermittently connected to the network.

Electrocardiography, while it has been digital for over 25 years, remains largely an island of information that is poorly integrated into the overall hospital information environment. IHE has addressed all of these issues already in its first year of cardiology activity. There will, of course, be some delay as products with these capabilities are introduced into the market. The legacy systems must either be updated or replaced to achieve the full benefits. But the effort is well under way.

Q: What are IHE integration profiles and how do they apply to cardiology?

The cardiology integration profiles focus on three areas: cardiac catheterization, echocardiography, and electrocardiography. Several "actors" communicate using "transactions." Examples of actors would be the acquisition modality (such as an echo cart or x-ray system that acquires and creates medical images), the admission/discharge/transfer system that keeps track of patient demographics and encounter information, image archives, image display systems, and so on.

Transactions are interactions between actors that share the required information using standardized messages. Examples of transactions include patient registration, order management, procedure scheduled, patient update, query images, and retrieve images. The Cardiology Technical Framework elaborates various workflow use cases that describe how these actors and transactions interact to handle various clinical scenarios.

For cardiac catheterization, there are eight scenarios defined, depending on whether the patient has been registered before the procedure (and which system did the registration), and whether an order had be placed (and which system did the ordering). We have specified what should happen when patient information is updated during the procedure and what to do if the patient is moved to a different procedure room or if the procedure is cancelled.

For echocardiography, there are similar workflow profiles with regard to patient registration and orders. In addition, the information flow related to a device that is connected intermittently to the network is specified, along with more detailed requirements for the labeling of images taken during stress studies.

Finally, for ECG, the profiles describe a standardized way to query information about available ECGs for a patient and a uniform way for a displayable ECG to be made available.

Q: This year, the IHE will be demonstrated at the ACC meeting. What will be accomplished by this demonstration?

Equipment vendors have worked very hard to bring the integration specified by IHE Technical Profiles for Cardiology to their products. In January, we held a week-long connect-a-thon in Chicago, where vendors brought together 110 computer systems (30 of which were cardiology systems). We tested all aspects of integration and of sharing information among the various systems.

At the ACC meeting, these technical demonstrations will be presented from a more clinical point of view showing solutions to real-world problems faced by hospitals today. We will walk through one scenario that shows how several systems coordinate information and images as a patient with an acute myocardial infarction is transferred emergently to the cardiac catheterization laboratory, registered later in the hospital information system, then transferred to the coronary care unit.

Another scenario shows how an echo cart that is unplugged from the network can be used to image a registered patient, then have the patient demographics and images synchronized when it plugs back into the network. We showed improved precision in presenting stress echo images, displayed either by view or by stress stage.

Finally, we will show a standardized way of retrieving and displaying electrocardiograms throughout the hospital.

Overall, we are hoping to provide a hands-on demonstration and education session targeting clinicians, information technology specialists, administrators, and department managers. Few people today are clamoring for IHE in cardiology, but nearly everyone is demanding improved connectivity and integration. The demonstration at the ACC is our chance to show that these are one and the same. It is the IHE framework that will deliver the integration.

Q: Where can cardiologists go to learn more about the IHE?

The IHE and ACC Web sites.