Author + information
- Robert L. McNamara, MD, MHS, FACC, Chair, Writing Committee Member,
- Lawrence M. Brass, MD, FAHA, Writing Committee Member,
- Joseph P. Drozda Jr, MD, FACC, Writing Committee Member,
- Alan S. Go, MD, Writing Committee Member,
- Jonathan L. Halperin, MD, FACC, FAHA, Writing Committee Member,
- Charles R. Kerr, MD, FACC, Writing Committee Member,
- Samuel Lévy, MD, FACC, FAHA, Writing Committee Member,
- David J. Malenka, MD, FACC, Writing Committee Member,
- Suneet Mittal, MD, FACC, Writing Committee Member,
- Frank Pelosi Jr, MD, FACC, Writing Committee Member,
- Yves Rosenberg, MD, Writing Committee Member,
- Daniel Stryer, MD, Writing Committee Member,
- D.George Wyse, MD, PhD, FACC, FAHA, Writing Committee Member,
- Martha J. Radford, MD, FACC, FAHA,, Chair, Task Force Member,
- David C. Goff Jr, MD, PhD, FAHA, Task Force Member,
- Frederick L. Grover, MD, FACC, Task Force Member,
- Paul A. Heidenreich, MD, FACC, Task Force Member,
- David J. Malenka, MD, FACC, Task Force Member,
- Eric D. Peterson, MD, FACC, FAHA, Task Force Member and
- Rita F. Redberg, MD, MSc, FACC, FAHA, Task Force Member
1. Introduction 477
1.1. Purpose 477
2. Methodology 477
2.1. Writing Committee Composition 477
2.2. Review of Literature and Existing Data Definitions 477
2.3. Prioritizing Data Elements 477
2.4. Defining Data Elements 477
2.5. Writing Considerations for Use 478
2.6. Consensus Development 478
2.7. Peer Review, Public Comment, and Board Approval 478
2.8. Document Format 478
3. General Considerations of the AF Clinical Data Standards 478
3.1. Patient-Oriented Format 478
3.2. Balance Between Focus and Comprehensiveness 478
3.3. Dates 478
3.4. Varied Clinical Presentations 478
3.5. Balance Between Primary and Summary Data Elements 478
3.6. Atrial Fibrillation-Specific Elements 478
3.7. Quality of Life 479
3.8. Atrial Flutter and Other Atrial Tachycardias 479
4. Atrial Fibrillation Clinical Data Elements and Definitions 479
4.1. Retrospective and Concurrent Data (collected at or near the time of study initiation) 480
4.2. Prospective Data (collected after enrolling in study) 486
Appendix A: External Peer Reviewers 494
The American College of Cardiology (ACC) and the American Heart Association (AHA) recognize the importance of refining the lexicon used to describe the process and outcomes of clinical care, whether in randomized trials, observational studies, registries, or quality-improvement initiatives. Broad professional agreement on a common vocabulary with common definitions will facilitate cross-study comparisons or, when advantageous, combining of data across studies and will improve the assessment of any project's generalizability to clinical practice. To further efforts aimed at standardizing such a lexicon, the ACC and AHA have undertaken to develop and publish clinical data standards, sets of standardized data elements and corresponding definitions that can be used in a variety of data collection efforts for a range of cardiovascular conditions.
It is hoped that these clinical data standards will:
1. Improve cross-comparison of results and clinical outcomes between different trials and registries.
2. Facilitate the development and conduct of future registries, at both hospital and national levels, by providing a list of major variables, outcomes, and definitions.
3. Facilitate measurement for quality-improvement programs.
4. Become the basis for a standardized charting process with the anticipation that medical charting will progress to an electronic format.
The ACC/AHA Task Force on Clinical Data Standards makes every effort to avoid any actual or potential conflicts of interest that might arise as a result of an outside relationship or a personal interest of a member of the writing panel. Specifically, all members of the writing panel are asked to provide disclosure statements of all such relationships that might be perceived as real or potential conflicts of interest. These statements are reviewed by the parent task force, reported orally to all members of the writing panel at the first meeting, and updated as changes occur.
The ACC/AHA Task Force on Clinical Data Standards selects cardiovascular conditions and procedures that would benefit from the creation of a data standard set. Experts in the subject are selected to examine/consider existing data standards and develop a comprehensive, yet not exhaustive, data standard set. Users should understand that when they undertake a data collection effort, only a subset may be needed, or conversely, they may want to consider whether it may be necessary to collect some elements not listed. For example, in the setting of a randomized clinical trial of a new drug, additional information would likely be required regarding study procedures and drug therapies.
The ACC and AHA aim to standardize the language used to describe cardiovascular diseases and procedures, enhance consistency in cardiology, and increase opportunities for sharing data across various data sources. The ultimate goal of ACC/AHA clinical data standards is to contribute to the infrastructure necessary for accomplishing the ACC/AHA's mission of fostering optimal cardiovascular care and disease prevention.
The ACC and AHA support the goals of its members to improve cardiovascular care and disease prevention through professional education, promotion of research, development of guidelines and standards for cardiovascular care, and the fostering of policy that supports optimal patient outcomes. The ACC and AHA recognize the importance of the use of clinical data for patient management, in the assessment of patient outcomes, and in research efforts focused on improving clinical treatment of patients.
As a component of this objective, the ACC/AHA clinical data standards concentrate on the identification, definition, and standardization of data that correspond to various clinical topics in cardiology. The primary goal of clinical data standards is to assist in the collection of data by providing an initial platform of data elements and corresponding definitions applicable to various disease conditions in cardiology. These key elements and definitions are a compilation of variables applicable in the measurement of patient clinical management and outcomes and for research and epidemiological assessments.
The Health Insurance Portability and Accountability Act (HIPAA) privacy regulations, which went into effect in April 2003, have heightened all practitioners' awareness of our professional commitment to safeguard our patients' privacy. Our goal is to treat every patient's health information with the same respect and courtesy as their person. The HIPAA privacy regulations (http://www.hhs.gov/ocr/combinedregtext.pdf, page 31) specify which information elements are considered “protected health information.” These elements may not be disclosed to third parties (including registries and research studies) without the patient's written permission, and research studies that use protected health information must be reviewed by an Institutional Review Board or a Privacy Board.
We have included identifying information in all clinical data standards to facilitate uniform collection of these elements when appropriate. For example, a longitudinal clinic database may contain these elements, because access is restricted to the patient's caregivers. On the other hand, registries may not contain protected health information unless specific permission is granted by each patient. These fields are indicated as protected health information (PHI) in the data standards.
Our understanding of the importance of data element standardization, derives from experience with clinical care, clinical research, and quality-performance measurement. In clinical care, caregivers communicate with each other through a common vocabulary. The integrity of clinical research depends in large part on firm adherence to prespecified procedures for patient enrollment and follow-up; these procedures are guaranteed through careful attention to definitions enumerated in the study design and case report forms. When data elements and definitions are standardized across studies, comparison, pooled analysis, and meta-analysis are facilitated, thus deepening our understanding of individual clinical trials.
The recent development of quality-performance measurement initiatives, particularly those for which comparison of providers is an implicit or explicit aim, has further raised awareness among the professional community about the importance of data standards. For the first time, a wide audience, including nonmedical professionals such as payers, regulators, and consumers, may draw conclusions about care and outcomes. For comparison of care patterns and outcomes to be fair, the data elements that compose the descriptions of these patterns and outcomes of care must be clearly defined, consistently used, and properly interpreted by a broader audience than ever before.
Martha J. Radford, MD, FACC, FAHA
Chair, ACC/AHA Task Force on Clinical Data Standards
Atrial fibrillation (AF) is the most common arrhythmia encountered in clinical practice. Prevalence of AF increases with age, reaching as high as 9% in octogenarians 1–4. New pharmacological and nonpharmacological treatments, as well as results from some large clinical trials 5–7, have increased interest in the management of AF. To address this increased need and interest, the American College of Cardiology (ACC), the American Heart Association (AHA), and the European Society of Cardiology (ESC) jointly released the ACC/AHA/ESC Guidelines for the Management of Patients With Atrial Fibrillation 8. The ACC and AHA are following this effort with the ACC/AHA Key Data Elements and Definitions for Measuring the Clinical Management and Outcomes of Patients With Atrial Fibrillation. AF is one of several conditions identified for development of clinical data standards by the ACC/AHA Task Force on Clinical Data Standards and is preceded by clinical data standards on acute coronary syndrome.
The ACC/AHA Atrial Fibrillation Data Standards Writing Committee proceeded to develop data elements and definitions with the goal that they may be useful in a variety of circumstances:
• Clinical programs, where many providers and health plans work together to achieve specific goals for the care of patients with AF. Data standards will assist in the organization and design of electronic medical information initiatives, such as electronic medical records, pharmacy and other clinical databases, or computerized decision support.
• Clinical research, including prospective registries and randomized controlled trials (RCTs). Meta-analyses of RCTs would be particularly strengthened by the use of standardized data for key variables.
• Quality-performance measurement initiatives. Data standards will especially facilitate interpretation for nonmedical users, such as payers, regulators, and consumers.
These data standards were designed to facilitate the above initiatives. Because they were developed to support many varied uses, they were not designed to provide an operational format for any one specific use. Thus, the definitions are often stated in a more general fashion than will be appropriate for certain purposes. More specific operational definitions likely will be used for actual data collection, with these data standards providing a uniform guide for their development. In addition, because the data standards were developed for potential application in varied environments, all elements are not expected to pertain to each application.
A. Writing committee composition
The ACC/AHA Writing Committee to Develop Clinical Data Standards for Atrial Fibrillation included a group of 13 physicians who are active in clinical programs, clinical research, and/or quality-performance measurement initiatives in AF. To improve generalization to a broad population, the committee included membership from the United States, France, and Canada. To ensure consistency within the topic of AF, the committee included three members from the ACC/AHA/ESC Committee to Develop Guidelines for the Management of Patients With Atrial Fibrillation. To enhance uniformity among different data standards efforts, the committee included one member from the ACC/AHA Task Force on Clinical Data Standards.
B. Review of literature and existing data definitions
The AF data standards are intended to provide data elements that parallel and complement other ACC and AHA standards, specifically guidelines. The ACC/AHA/ESC Guidelines for the Management of Patients With Atrial Fibrillation 8 served as the primary evidence-based document that was referenced in the development of data elements and definitions for this statement. The writing committee gathered as many additional candidate data elements and definitions as possible from large clinical trials, national quality-performance measurement initiatives, relevant guidelines, and other national, international, and local cardiovascular data collection efforts. Examples of these data sources include the Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) 7,9, the AnTicoagulation and Risk factors In Atrial fibrillation (ATRIA) Study 4, the ALFA Study (Etude en Activité Liberale sur le Fibrillation Auriculaire) 10, the Canadian Trial of Atrial Fibrillation 11,12, and the Canadian Registry of Atrial Fibrillation (CARAF) 13.
C. Prioritizing data elements
Once the writing committee reviewed the relevant literature and additional resources, a comprehensive list of potential items was created with the understanding that the final set would be limited to those elements most likely to be needed in data collection efforts. The initial list of data elements was graded according to priority as “high,” “medium,” or “low.” All of the data elements with an average “high” score and a majority of those with an average “medium” score were included in the final set. The remaining elements are not included at this time but may be added and defined in the future.
The subsequent process of writing and revising data element definitions included prioritizing, adding, and removing elements for the purpose of defining the elements in a manner that facilitates consistent data collection.
D. Defining data elements
Members of the writing committee were assigned to one of four working groups, each of which was responsible for drafting definitions for a subset of data elements deemed to have priority for the first publication of the AF data standards. Each writer received a template to assist in drafting the definitions and to provide for a structured format across authors. Writers were encouraged to compose definitions that were broad enough to be applicable in a variety of data collection settings (e.g., inpatient versus outpatient) but specific enough that the data elements could be uniformly interpreted.
To ensure consistency across ACC/AHA clinical data standards and clinical guidelines, previously published definitions were used verbatim whenever appropriate. Furthermore, data element definitions were linked to pre-existing definitions.
E. Writing considerations for use
The writing committee determined three major settings in which these data elements may be particularly useful: clinical care, clinical research, and quality-performance measurement.
F. Consensus development
The ACC/AHA data standards are consensus, team-written documents that are based on judgments of experts in the field of cardiology. This writing committee met several times, both in person and through conference calls, over the course of 18 months to define and refine the data elements and definitions. Consensus was met through meetings, conference calls, and e-mailcommunications.
G. Peer review, public comment, and board approval
The set of AF data elements was reviewed by 6 official reviewers nominated by the ACC, AHA, and the ACC/AHA Task Force on Clinical Data Standards and 10 individual content reviewers (see Appendix Afor names and affiliations). To increase its applicability further, the document was posted on the ACC World Wide Web site for a 30-day public comment period between July 30 and August 30, 2003. Response forms were received from 63 individuals, representing 15 countries, including the United States. The document was approved for publication by the governing bodies of the ACC and the AHA. The document has been formally endorsed by the Mediterranean Society of Pacing and Electrophysiology. To determine whether a revision is necessary, these clinical data standards will be reviewed one year after publication and yearly thereafter by the ACC/AHA Task Force on Clinical Data Standards.
H. Document format
This document is divided into three sections, outlined as follows:
1. Introduction: A description of the methodology for developing the AF clinical data standards and intended goals for their use.
2. Data Elements and Definitions: A listing of key data elements and definitions.
3. Reference Guide: A multipurpose resource that maps common data fields between AF data elements and other national/regional data registries and links AF data elements to relevant ACC/AHA guidelines (available online at www.acc.org/clinical/data_standards/AF/pdf/AF_refguide.pdf).
III. General considerations of the AF clinical data standards
A. Patient-oriented format
Given that AF is a chronic condition, the individual patient is the foundation of this data element set. This focus contrasts with other comparable efforts in which the field of interest may be a procedure (e.g., cardiac catheterization) or an event (e.g., acute coronary syndrome). Thus, the format of these data elements was designed to follow multiple events over time for each individual patient.
B. Balance between focus and comprehensiveness
The writing committee focused on commonly collected data elements that were thought to be most useful for the broadest set of applications. These data standards are not intended to be a comprehensive data element catalog, encompassing every possible data need or use. The writing committee realizes that individual users likely will supplement these elements to suit their individual needs. Conversely, other users will select only a few data elements to collect.
The committee recognizes the critical importance of obtaining dates for most data elements in order to understand the clinical course, therapy, and outcomes of AF for the individual patient and across populations. The exact date (month, day, and year) for all elements and dates of events for prospective data elements should be obtained whenever possible. Because the ability to obtain precise dates of prior events is limited, best estimate of dates should be obtained (e.g., month/year), with emphasis placed on the most current events. The operational format of date collection will vary depending on particular use.
D. Varied clinical presentations
These data elements are intended to encompass the full range of patients with AF, including acute and chronic presentations, inpatient and outpatient settings, and scheduled and unscheduled medical care encounters.
E. Balance between primary and summary data elements
These data elements consist of both individual data elements (for example, age and left atrial size) and summary elements (for example, New York Heart Association [NYHA] class for heart failure and primary cardiac diagnosis). In general, the committee included summary elements only to supplement primary data elements.
F. Atrial fibrillation-specific elements
When possible, the committee chose data element names and definitions common to other ACC/AHA clinical data standard efforts. However, some elements were designed to specifically meet the needs of patients with AF. The committee wanted to highlight a subset of these AF-specific elements that were particularly noteworthy. These elements appear in bold print in the “Element” column. They are:
Section II. A. Retrospective Data
• Qualifying cardiac rhythm
• Predominant cardiac diagnosis
• Atrial fibrillation due to transient or reversible cause
• Previously used therapeutic strategies
• Frequency of prior symptomatic episodes
• Duration of prior symptomatic episodes
Section II. B. Prospective Data
• Primary reason for encounter
• Patient classification of type of AF episodes
• Current management strategy
Quality of Life:
• Symptoms with prior episodes of AF
• Success of cardioversion attempt
• Pattern of recurrence
• Complications of conversion
• Primary reason for admission
• Procedures performed
• Specialty of principal provider
G. Quality of life
Considerations of quality of life are particularly important in the management of AF. The currently available general health status measures, such as EuroQOL (www.euroqol.org), the SF-36 14, or the SF-12 15, are valuable in the breadth of domains that they measure and in their use for comparison across disease states. However, valid and reliable measures focused on the specific health burdens of AF are needed to supplement general health status measures. These focused measures may quantify health status effects of the arrhythmia itself, such as the AF Severity Scale and AF Symptom Burden Checklist used by the Canadian Registry of Atrial Fibrillation 16; of complications, such as stroke (National Institutes of Health Stroke Scale 17); or of therapy, such as inconvenience and lifestyle changes associated with chronic warfarin therapy 18. At this point, no single approach to measurement of health status of patients with AF can be recommended.
H. Atrial flutter and other atrial tachycardias
Although many elements and definitions within this document will apply to patients with atrial flutter and other atrial tachycardias, the identification and definition of the unique features of these rhythms are not within the scope of this document.
American College of Cardiology Foundation
Christine W. McEntee, Chief Executive Officer
Frances F. Fiocchi, MPH, Senior Specialist, Research and Innovation
Susan L. Morrisson, Associate Specialist, Clinical Policy and Documents
American Heart Association
M. Cass Wheeler, Chief Executive Officer
Rose Marie Robertson, MD, FACC, FAHA, Chief Science Officer
Fernando Costa, MD, FAHA, Staff Scientist
IV. Atrial fibrillation clinical data elements and definitions
Appendix A External Peer Reviewers
|Reviewer Name†||Reviewer Category and Affiliation|
|W. Barton Campbell, MD, FACC||ACC Board of Governors|
|Valentin Fuster, MD, PhD, FACC||ACC/AHA Task Force on Practice Guidelines|
|Bruce Lindsay, MD, FACC||ACC Board of Trustees|
|Martha Radford, MD, FACC, FAHA||ACC/AHA Task Force on Data Standards Lead Reviewer|
|David Sherman, MD, FAHA||AHA Reviewer, Neurology|
|Albert Waldo, MD, FACC, FAHA||AHA Reviewer|
|A. John Camm, MD, FACC||Individual|
|Jamie Conti, MD, FACC||Individual|
|James Emery, MD, FACC||ACC Board of Governors Secondary Reviewer|
|Linda Gillam, MD, FACC||Individual|
|David Goff, MD||Individual|
|Robert Hong, MD, FACC||ACC Board of Governors Secondary Reviewer|
|Ira Nash, MD, FACC||Individual|
|Richard Page, MD, FACC||Individual|
|Edward Pritchett, MD, FACC||Individual|
|Denis Roy, MD, FACC||Individual|
☆ This document was approved by the American College of Cardiology Board of Trustees in February 2004 and the American Heart Association Science Advisory and Coordinating Committee in January 2004.
When citing this document, the American College of Cardiology Foundation and the American Heart Association would appreciate the following citation format: McNamara RL, Brass LM, Drozda JP Jr, Go AS, Halperin JL, Kerr CR, Lévy S, Malenka DJ, Mittal S, Pelosi F Jr, Rosenberg Y, Stryer D, Wyse DG. ACC/AHA key data elements and definitions for measuring the clinical management and outcomes of patients with atrial fibrillation: a report of the ACC/AHA Task Force on Clinical Data Standards (Writing Committee to Develop Data Standards on Atrial Fibrillation). J Am Coll Cardiol 2004;44:475–95.
Copies: This document is available on the World Wide Web sites of the American College of Cardiology (www.acc.org) and the American Heart Association (www.americanheart.org). Single copies of this document as published in the July 21, 2004, issue of the Journal of the American College of Cardiology and the June 29, 2004, issue of Circulation or its companion online Reference Guide are available for $10.00 each by calling 1-800-253-4636 or writing the American College of Cardiology Foundation, Resource Center, at 9111 Old Georgetown Road, Bethesda, MD 20814-1699. To purchase bulk reprints (specify version and reprint number—71-0290 for the published document; 71-0297 for the Reference Guide): Up to 999 copies, call 1-800-611-6083 (US only) or fax 413-665-2671; 1000 or more copies, call 214-706-1789, fax 214-691-6342, or e-mail .
Permissions: Multiple copies, modification, alteration, enhancement and/or distribution of this document are not permitted without the express permission of the American College of Cardiology Foundation. Please direct requests to. (J Am Coll Cardiol 2004;44:475–95.)
© 2004 by the American College of Cardiology Foundation and the American Heart Association, Inc.;doi:10.1016/j.jacc.2004.06.04
Endorsed by the Mediterranean Society of Pacing and Electrophysiolgy
- American College of Cardiology Foundation
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