ACC/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities: Executive Summary: A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the ACC/AHA/NASPE 2002 Guideline Update for Implantation of Cardiac Pacemakers and Antiarrhythmia Devices) Developed in Collaboration With the American Association for Thoracic Surgery and Society of Thoracic Surgeons FREE

Sidney C. Smith, Jr, MD, FACC, FAHA, Chair

Alice K. Jacobs, MD, FACC, FAHA, Vice-Chair

Cynthia D. Adams, RN, PhD, FAHA§

Jeffrey L. Anderson, MD, FACC, FAHA§

Christopher E. Buller, MD, FACC

Mark A. Creager, MD, FACC, FAHA

Steven M. Ettinger, MD, FACC

David P. Faxon, MD, FACC, FAHA§

Jonathan L. Halperin, MD, FACC, FAHA§

Loren F. Hiratzka, MD, FACC, FAHA§

Sharon A. Hunt, MD, FACC, FAHA§

Harlan M. Krumholz, MD, FACC, FAHA

Frederick G. Kushner, MD, FACC, FAHA

Bruce W. Lytle, MD, FACC, FAHA

Rick A. Nishimura, MD, FACC, FAHA

Joseph P. Ornato, MD, FACC, FAHA§

Richard L. Page, MD, FACC, FAHA

Barbara Riegel, DNSc, RN, FAHA§

Lynn G. Tarkington, RN

Clyde W. Yancy, MD, FACC, FAHA

It is important that the medical profession play a significant role in critically evaluating the use of diagnostic procedures and therapies as they are introduced and tested in the detection, management, or prevention of disease states. Rigorous and expert analysis of the available data documenting absolute and relative benefits and risks of those procedures and therapies can produce helpful guidelines that improve the effectiveness of care, optimize patient outcomes, and favorably affect the overall cost of care by focusing resources on the most effective strategies.

The American College of Cardiology Foundation (ACCF) and the American Heart Association (AHA) have jointly engaged in the production of such guidelines in the area of cardiovascular disease since 1980. The American College of Cardiology (ACC)/AHA Task Force on Practice Guidelines, whose charge is to develop, update, or revise practice guidelines for important cardiovascular diseases and procedures, directs this effort. Writing committees are charged with the task of performing an assessment of the evidence and acting as an independent group of authors to develop, update, or revise written recommendations for clinical practice.

Experts in the subject under consideration have been selected from both organizations to examine subject-specific data and write guidelines. The process includes additional representatives from other medical practitioner and specialty groups when appropriate. Writing committees are specifically charged to perform a formal literature review, weigh the strength of evidence for or against a particular treatment or procedure, and include estimates of expected health outcomes where data exist. Patient-specific modifiers and comorbidities and issues of patient preference that may influence the choice of particular tests or therapies are considered, as well as frequency of follow-up and cost-effectiveness. When available, information from studies on cost will be considered; however, review of data on efficacy and clinical outcomes will constitute the primary basis for preparing recommendations in these guidelines.

The ACC/AHA Task Force on Practice Guidelines makes every effort to avoid any actual, potential, or perceived conflicts of interest that may arise as a result of an industry relationship or personal interest of the writing committee. Specifically, all members of the writing committee, as well as peer reviewers of the document, were asked to provide disclosure statements of all such relationships that may be perceived as real or potential conflicts of interest. Writing committee members are also strongly encouraged to declare a previous relationship with industry that may be perceived as relevant to guideline development. If a writing committee member develops a new relationship with industry during his or her tenure, he or she is required to notify guideline staff in writing. The continued participation of the writing committee member will be reviewed. These statements are reviewed by the parent task force, reported orally to all members of the writing committee at each meeting, and updated and reviewed by the writing committee as changes occur. Please refer to the methodology manual for ACC/AHA guideline writing committees for further description of the relationships with industry policy (1). See Appendix 1 for author relationships with industry and Appendix 2 for peer reviewer relationships with industry that are pertinent to this guideline.

These practice guidelines are intended to assist health care providers in clinical decision making by describing a range of generally acceptable approaches for the diagnosis, management, and prevention of specific diseases or conditions. Clinical decision making should consider the quality and availability of expertise in the area where care is provided. These guidelines attempt to define practices that meet the needs of most patients in most circumstances. These guideline recommendations reflect a consensus of expert opinion after a thorough review of the available current scientific evidence and are intended to improve patient care.

Patient adherence to prescribed and agreed upon medical regimens and lifestyles is an important aspect of treatment. Prescribed courses of treatment in accordance with these recommendations will only be effective if they are followed. Because lack of patient understanding and adherence may adversely affect treatment outcomes, physicians and other health care providers should make every effort to engage the patient in active participation with prescribed medical regimens and lifestyles.

If these guidelines are used as the basis for regulatory or payer decisions, the ultimate goal is quality of care and serving the patient's best interests. The ultimate judgment regarding care of a particular patient must be made by the health care provider and the patient in light of all of the circumstances presented by that patient. There are circumstances in which deviations from these guidelines are appropriate.

The guidelines will be reviewed annually by the ACC/AHA Task Force on Practice Guidelines and will be considered current unless they are updated, revised, or sunsetted and withdrawn from distribution. The executive summary and recommendations are published in the May 27, 2008, issue of the Journal of the American College of Cardiology, May 27, 2008, issue of Circulation, and the June 2008 issue of Heart Rhythm. The full-text guidelines are e-published in the same issue of the journals noted above, as well as posted on the ACC (www.acc.org), AHA (http://my.americanheart.org), and Heart Rhythm Society (HRS) (www.hrsonline.org) Web sites. Copies of the full-text and the executive summary are available from each organization.

Sidney C. Smith, Jr, MD, FACC, FAHA Chair, ACC/AHA Task Force on Practice Guidelines

This revision of the “ACC/AHA/NASPE Guidelines for Implantation of Cardiac Pacemakers and Antiarrhythmia Devices” updates the previous versions published in 1984, 1991, 1998, and 2002. Revision of the statement was deemed necessary for multiple reasons: 1) Major studies have been reported that have advanced our knowledge of the natural history of bradyarrhythmias and tachyarrhythmias, which may be treated optimally with device therapy; 2) there have been tremendous changes in the management of heart failure that involve both drug and device therapy; and 3) major advances in the technology of devices to treat, delay, and even prevent morbidity and mortality from bradyarrhythmias, tachyarrhythmias, and heart failure have occurred.

The committee to revise the “ACC/AHA/NASPE Guidelines for Implantation of Cardiac Pacemakers and Antiarrhythmia Devices” was composed of physicians who are experts in the areas of device therapy and follow-up and senior clinicians skilled in cardiovascular care, internal medicine, cardiovascular surgery, ethics, and socioeconomics. The committee included representatives of the American Association for Thoracic Surgery, Heart Failure Society of America, and Society of Thoracic Surgeons.

The document was reviewed by 2 official reviewers nominated by each of the ACC, AHA, and HRS and by 11 additional peer reviewers. Of the total 17 peer reviewers, 10 had no significant relevant relationships with industry. In addition, this document has been reviewed and approved by the governing bodies of the ACC, AHA, and HRS, which include 19 ACC Board of Trustees members (none of whom had any significant relevant relationships with industry), 15 AHA Science Advisory Coordinating Committee members (none of whom had any significant relevant relationships with industry), and 14 HRS Board of Trustees members (6 of whom had no significant relevant relationships with industry). All guideline recommendations underwent a formal, blinded writing committee vote. Writing committee members were required to recuse themselves if they had a significant relevant relationship with industry. The guideline recommendations were unanimously approved by all members of the writing committee who were eligible to vote.

The recommendations listed in this document are, whenever possible, evidence based. An extensive literature survey was conducted and limited to studies, reviews, and other evidence conducted in human subjects and published in English. Additionally, the committee reviewed documents related to the subject matter previously published by the ACC, AHA, and HRS. References selected and published in this document are representative and not all-inclusive.

The committee reviewed and ranked evidence supporting current recommendations, with the weight of evidence ranked as Level A if the data were derived from multiple randomized clinical trials that involved a large number of individuals. The committee ranked available evidence as Level B when data were derived either from a limited number of trials that involved a comparatively small number of patients or from well-designed data analyses of nonrandomized studies or observational data registries. Evidence was ranked as Level C when the consensus of experts was the primary source of the recommendation. In the narrative portions of these guidelines, evidence is generally presented in chronological order of development. Studies are identified as observational, randomized, prospective, or retrospective. The committee emphasizes that for certain conditions for which no other therapy is available, the indications for device therapy are based on expert consensus and years of clinical experience and are thus well supported, even though the evidence was ranked as Level C. An analogous example is the use of penicillin in pneumococcal pneumonia, for which there are no randomized trials and only clinical experience. When indications at Level C are supported by historical clinical data, appropriate references (e.g., case reports and clinical reviews) are cited if available. When Level C indications are based strictly on committee consensus, no references are cited. In areas where sparse data were available (e.g., pacing in children and adolescents), a survey of current practices of major centers in North America was conducted to determine whether there was a consensus regarding specific pacing indications.

The schema for classification of recommendations and level of evidence is summarized in (Table 1), which also illustrates how the grading system provides an estimate of the size of the treatment effect and an estimate of the certainty of the treatment effect.

The focus of these guidelines is the appropriate use of devices (e.g., pacemakers for bradyarrhythmias and heart failure management, cardiac resynchronization, and implantable cardioverter-defibrillators [ICDs]), not the treatment of cardiac arrhythmias. The fact that the use of a device for treatment of a particular condition is listed as a Class I indication (beneficial, useful, and effective) does not preclude the use of other therapeutic modalities that may be equally effective. As with all clinical practice guidelines, the recommendations in this document focus on treatment of an average patient with a specific disorder and may be modified by patient comorbidities, limitation of life expectancy because of coexisting diseases, and other situations that only the primary treating physician may evaluate appropriately.

The term “symptomatic bradycardia” is used in this document. Symptomatic bradycardia is defined as a documented bradyarrhythmia that is directly responsible for development of the clinical manifestations of syncope or near syncope, transient dizziness or lightheadedness, or confusional states resulting from cerebral hypoperfusion attributable to slow heart rate. Fatigue, exercise intolerance, and congestive heart failure may also result from bradycardia. These symptoms may occur at rest or with exertion. Definite correlation of symptoms with a bradyarrhythmia is required to fulfill the criteria that define symptomatic bradycardia. Caution should be exercised not to confuse physiological sinus bradycardia (as occurs in highly trained athletes) with pathological bradyarrhythmias. Occasionally, symptoms may become apparent only in retrospect after antibradycardia pacing. Nevertheless, the universal application of pacing therapy to treat a specific heart rate cannot be recommended except in specific circumstances, as detailed subsequently.

In these guidelines, the terms “persistent,” “transient,” and “not expected to resolve” are used but not specifically defined because the time element varies in different clinical conditions. The treating physician must use appropriate clinical judgment and available data in deciding when a condition is persistent or when it can be expected to be transient.

Recommendations for ICD implantation have been updated to reflect the numerous new developments in this field and the voluminous literature related to the efficacy of these devices in the treatment and prophylaxis of sudden cardiac death (SCD) and malignant ventricular arrhythmias. Indications for ICDs, cardiac resynchronization therapy (CRT) devices, and combined ICDs and CRT devices are continuously changing and can be expected to change further as new trials are reported. Indeed, it is inevitable that the indications for device therapy will be refined with respect to both expanded use and the identification of patients expected to benefit the most from these therapies. Furthermore, it is emphasized that when a patient has an indication for both a pacemaker (whether it be single-chamber, dual-chamber, or biventricular) and an ICD, a combined device with appropriate programming is indicated.

The 2008 revision reflects what the committee believes are the most relevant and significant advances in pacemaker/ICD therapy since the publication of these guidelines in the Journal of the American College of Cardiology and Circulation in 2002 (2- 3).

All recommendations assume that patients are treated with optimal medical therapy according to published guidelines, as had been required in all the randomized controlled clinical trials on which these guidelines are based. The committee believes that comorbidities, life expectancy, and quality-of-life issues must be addressed forthrightly with patients and their families. We have repeatedly used the phrase “reasonable expectation of survival with a good functional status for more than 1 year” to emphasize this integration of factors in decision making. Even when physicians believe that the anticipated benefits warrant device implantation, patients have the option to decline intervention after having been provided with a full explanation of the potential risks and benefits of device therapy. Finally, the committee is aware that other guidelines/expert groups have interpreted the same data differently (4- 7).

In preparing this revision, the committee was guided by the following principles:

The following represents the complete set of recommendations for the implantation of antiarrhythmia devices. Prior executive summaries of ACC/AHA guidelines have included variable amounts of explanatory text ranging from none to large amounts. Because the supporting text in the full-text document was important to the present writing committee, we decided to provide only the recommendations in the Executive Summary and recommend readers access the full-text document for more explanation. (Table 2) and (Figures 1, 2) are provided to help practitioners choose which pacing device is appropriate for an individual patient.

Secondary prevention refers to the prevention of SCD in those patients who have survived a prior cardiac arrest or sustained VT. Primary prevention refers to the prevention of SCD in individuals without a history of cardiac arrest or sustained VT. Patients with cardiac conditions associated with a high risk of sudden death who have unexplained syncope that is likely to be due to ventricular arrhythmias are considered to have a secondary indication.

Recommendations for consideration of ICD therapy, particularly those for primary prevention, apply only to patients who are receiving optimal medical therapy and have a reasonable expectation of survival with good functional status for more than 1 year. It is difficult to estimate survival with heart failure in the general population, for whom comorbidities and age differ from those in trial populations from which the predictive models have been derived. Patients with repeated heart failure hospitalizations, particularly in the presence of reduced renal function, are at high risk for early death due to heart failure (128- 130). Please see (6), “Indications for Implantable Cardioverter-Defibrillator Therapy,” in the full-text guidelines for discussion regarding the use of LVEFs on the basis of trial inclusion criteria.

We acknowledge that the “ACC/AHA/ESC 2006 Guidelines for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death” (4) used an LVEF of less than 40% as a critical point to justify ICD implantation for primary prevention of SCD. The LVEF used in clinical trials assessing the ICD for primary prevention of SCD ranged from less than 40% in MUSTT (Multicenter Unsustained Ventricular Tachycardia Trial) to less than 30% in MADIT II (Multicenter Automatic Defibrillator Implantation Trial II) (131- 132). Two trials, MADIT I (Multicenter Automatic Defibrillator Implantation Trial I) (6) and SCD-HeFT (Sudden Cardiac Death in Heart Failure Trial) (7) used LVEFs of less than 35% as entry criteria. The present writing committee reached the consensus that it would be best to offer ICDs to patients with clinical profiles as similar to those included in the trials as possible. Having given careful consideration to the issues related to LVEF for these updated ICD guidelines, we have written these indications for ICDs on the basis of the specific inclusion criteria for LVEF in the trials. Because of this, there may be some variation from previously published guidelines (4).

We also acknowledge that the determination of LVEF lacks a “gold standard” and that there may be variation among the commonly used clinical techniques of LVEF determination. All clinical methods of LVEF determination lack precision, and the accuracy of techniques varies among laboratories and institutions. On the basis of these considerations, the present writing committee recommends that clinicians use the LVEF determination that they believe is the most clinically accurate and appropriate in their institution.

American College of Cardiology Foundation

John C. Lewin, MD, Chief Executive Officer

Charlene May, Senior Director, Clinical Policy and Guidelines

Lisa Bradfield, Associate Director, Practice Guidelines

Mark D. Stewart, MPH, Associate Director, Evidence-Based Medicine

Kristen N. Fobbs, MS, Senior Specialist, Practice Guidelines

Erin A. Barrett, Senior Specialist, Clinical Policy and Guidelines

American Heart Association

M. Cass Wheeler, Chief Executive Officer

Gayle R. Whitman, RN, PhD, FAAN, FAHA, Vice President, Office of Science Operations

Kathryn A. Taubert, PhD, FAHA, Senior Science Advisor