Integrating the Healthcare Enterprise Retrieve ECG for Display Profile Barry D. Brown, Mortara Instrument, Inc. ECG Profile co-editor IHE Cardiology Technical.

Integrating the Healthcare EnterpriseIntegrating the Healthcare Enterprise

Retrieve ECG for DisplayProfile

Barry D. Brown, Mortara Instrument, Inc.ECG Profile co-editor

IHE Cardiology Technical Committee

September 13-15, 2004 IHE Interoperability Workshop2

ECG NeedsECG NeedsECGs Accessible Everywhere!Need broad distribution of ECGs using ubiquitous technology (Web).– Allow medical applications to easily retrieve and

display ECGs in a platform/vendor neutral way.

High-quality ECG documents. Avoid artifacts on zoomed ECGs and arbitrary display geometries.– Vector images required (not rasterized)

Facilitate apps for serial comparison (side-by-side synchronized display).


Goal for Year 1Goal for Year 1

High ROI—value added problem solutions

Standards in place (HTTP, PDF, SVG)

No “political” challenges – just technical

Restricted scope for a “quick win”

Reuse successful IHE IT Infrastructure Retrieve Information for Display (RID) profile to meet similar needs


In Scope for Year 1In Scope for Year 1

Provide ECGs and related documents to enterprise

Reuse IHE-ITI RID – Retrieve list of documents; retrieve single

document– ECGs served in ready-to-display format (PDF,

SVG)

Limited extension for ECG-specific needs– Add requirements on display format and quality– Include XML-based ECG report list


Out of Scope for Year 1Out of Scope for Year 1

ECG acquisition and reading workflow.

ECG raw data interchange.

Export of reports to external repository.

Central management and configuration of ECG devices.


Year 1 StrategyYear 1 Strategy

Reuse IHE-ITI RID as it is:– Retrieve list of cardiology documents,

including ECGs in ready-to-display format (HTML)

– Retrieve single document, including an ECG

– ECGs served in ready-to-display formats (PDF, SVG)

– Compatibility with existing RID clients


Year 1 Strategy (cont.)Year 1 Strategy (cont.)

Make ECG-specific extensions to RID– Place requirements on ECG source to

ensure high-quality ECG documents.– Add ECG-specific request for list of ECGs

to be returned as XML allowing more client flexibility.

– Add SVG as allowed ECG document format.


PDFPDF

ECG Source required to support PDF so it is compatible with existing RID clients.

PDF is a common document type and most computers already have a viewer.

ECG Source required to use vector graphics for waveforms in PDF.– Gives high quality line drawings at any screen

resolution and zoom factor.– Rasterized (e.g. scanned, bitmapped) ECG

“images” not allowed.


Example ECG in PDF FormatExample ECG in PDF Format


SVGSVG

Scalable Vector Graphics – “XML Graphics for the Web” – a W3C standard.Well suited for line drawings (e.g. waveforms) in a XML/Web environment.Currently supported through web browser plug-ins.Allows scripting to enable advanced user-side display control.


Example ECG in SVG FormatExample ECG in SVG Format


Use Case D1: Simple DisplayUse Case D1: Simple Display

Display actor requests list of ECG documents for a specific patient ID.– RID profile SUMMARY-CARDIOLOGY request

returns list as HTML.– ECG profile SUMMARY-CARDIOLOGY-ECG

request returns list as XML with stylesheet.

Display actor requests a specific ECG document using a unique document ID.– The ID of the requested document may not have

been obtained from the previously retrieved list.


Example List as HTMLExample List as HTML


Use Case D2: Advanced DisplayUse Case D2: Advanced Display

Display actor requests list of ECG documents for a specific patient ID using ECG profile request type.– List of ECGs returned as structured XML.

Display actor parses structured document list to select related ECGs for serial comparison, for example.Display actor requests the specific ECG documents using the unique document IDs obtained in structured list above.Display actor displays the ECGs in a meaningful way.


ECG List XML DetailsECG List XML Details

IHE uses DICOM and HL7 standards, methods, and information models when appropriate.HL7 V3 has Reference Information Model (RIM) and modeling method for creating general healthcare messages.HL7 V3 method produces XML schema.XML schema for IHE ECG list developed using HL7 V3 modeling method.


ECG List HL7 V3 R-MIMECG List HL7 V3 R-MIM

IHEDocumentListclassCode*: <= ACTmoodCode*: <= EVNcode*: CD CWE [1..1] <= ActCodeactivityTime: TS [0..1]

DocumentInformationclassCode*: <= ACTmoodCode*: <= EVNid*: II [1..1]code: CD CWE [0..1] <= ActCodetitle: ST [0..1]text: ED [0..1]statusCode: CS CNE [0..1]effectiveTime: TS [0..1]

0..* documentInformationtypeCode*: <= COMP

component

PatientclassCode*: <= PSNdeterminerCode*: <= INSTANCEname: PN [0..1]administrativeGenderCode: CE CWE [0..1] <= AdministrativeGenderbirthTime: TS [0..1]

0..1 patientPatient

0..1 providerOrganization

PatientRoleclassCode*: <= PATid*: II [1..1]

1..1 patient *

typeCode*: <= RCTrecordTarget

IHEDocumentList(AABB_RM444448)

This contains information about a set of documentsreturned from an IHE “Request List of ECGs” request.

DeviceclassCode*: <= DEVdeterminerCode*: <= INSTANCEid: II [0..1]code: CE CWE [0..1] <= EntityCodemanufacturerModelName: SC CWE [0..1] <= ManufacturerModelNamesoftwareName: SC CWE [0..1] <= SoftwareName

0..1 assignedDevice

AssignedAuthorclassCode*: <= ASSIGNEDid: II [0..1]

0..1 assignedAuthor

typeCode*: <= AUTnoteText: ED [0..1]

author

OrganizationclassCode*: <= ORGdeterminerCode*: <= INSTANCEid: II [0..1]name: ON [0..1]


ECG List XML SchemaECG List XML Schema


ECG List XML Example (1/3)ECG List XML Example (1/3)






ECG List XML Example ECG List XML Example Formatted with StylesheetFormatted with Stylesheet


ECG List XML ExampleECG List XML ExampleSimple Serial Comparison App.Simple Serial Comparison App.


Serial Comparison ExampleSerial Comparison Example23-April-2004 13:45:02

23-April-2004 13:47:45


For more info:For more info:

IHE Cardiology Technical Framework Version 1.0 for Trial Implementation at:– www.rsna.org/ihe– www.acc.org/quality/ihe.htm

ECG List XML schema and example available at same location.

Submit questions and comments to:– http://forums.rsna.org

Integrating the Healthcare Enterprise Retrieve ECG for Display Profile Barry D. Brown, Mortara Instrument, Inc. ECG Profile co-editor IHE Cardiology Technical.

Documents

specific ecg document

configuration of ecg

ecg acquisition

ecgspecific request

highquality ecg documents

allowed ecg document

ecgspecific extensions

display ecgs