Appendix C
Review of ACC/AHA Clinical Practice Guidelines

BACKGROUND

The Social Security Administration (SSA) asked the Institute of Medicine (IOM) to analyze the clinical practice guidelines developed by the American College of Cardiology/American Heart Association (ACC/AHA) for their relevance to improving the criteria required to meet the cardiovascular listings.

ACC/AHA Letter

As part of its charge, IOM’s Committee on Social Security Cardiovascular Disability Criteria was asked to review the ACC/AHA cardiovascular practice guidelines. The guidelines to be reviewed were named in an ACC/AHA letter to SSA, dated June 16, 2008, that was sent to SSA in response to SSA’s Advance Notice of Proposed Rulemaking entitled “Revised Medical Criteria for Evaluating Cardiovascular Disorders,” which was published in the Federal Register on April 16, 2008 (Table 1 of that issue).

In its letter, ACC/AHA urged SSA to “base its proposals on evidence-based clinical practice guidelines” as it undertook the task of revising the criteria for cardiovascular disease.

SSA’s Charge to the Committee

In the committee’s statement of work, SSA tasked the committee with analyzing “the AHA and ACC guidelines to determine which, if any, guide-



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Appendix C Review of ACC/AHA Clinical Practice Guidelines BACKGROUND The Social Security Administration (SSA) asked the Institute of Medi- cine (IOM) to analyze the clinical practice guidelines developed by the American College of Cardiology/American Heart Association (ACC/AHA) for their relevance to improving the criteria required to meet the cardio- vascular listings. ACC/AHA Letter As part of its charge, IOM’s Committee on Social Security Cardiovas- cular Disability Criteria was asked to review the ACC/AHA cardiovascular practice guidelines. The guidelines to be reviewed were named in an ACC/ AHA letter to SSA, dated June 16, 2008, that was sent to SSA in response to SSA’s Advance Notice of Proposed Rulemaking entitled “Revised Medical Criteria for Evaluating Cardiovascular Disorders,” which was published in the federal Register on April 16, 2008 (Table 1 of that issue). In its letter, ACC/AHA urged SSA to “base its proposals on evidence- based clinical practice guidelines” as it undertook the task of revising the criteria for cardiovascular disease. SSA’s Charge to the Committee In the committee’s statement of work, SSA tasked the committee with analyzing “the AHA and ACC guidelines to determine which, if any, guide- 

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0 0 CaRdIoVaSCUlaR dISabIlIty lines have the potential to become indicators of disability as defined by SSA,” that is, to determine whether the guidelines would be useful in de- veloping listing criteria for evaluating disability. The guidelines identified by ACC/AHA are listed in Box C-1. ACC Briefing of IOM Committee James Fasules, M.D., senior vice president, advocacy, American Col- lege of Cardiology, participated in the first committee meeting to discuss the role of the ACC/AHA clinical practice guidelines in updating SSA’s cardiovascular disability criteria in the Listings. He indicated four potential contributions of the guidelines: 1. Comprehensive review of natural history of disease process; 2. Explicit guidance on activity restrictions and capabilities—a direct bearing on disability; 3. Consistent terminology for conditions and diagnostic and thera- peutic services; and 4. Guidance on standard of care for evaluation and treatment. The guidelines were relied on extensively in the report as the basis for descriptive, diagnostic, and treatment terminology for the diagnostic procedures and tests and recommended treatments that should be expected to be in the average medical record and required or assumed in the listing criteria, and for information about the natural history of each condition. They were also reviewed to see if they provided any guidance on activity limitations and capacity, which relate directly to disability criteria. Few of the guidelines contained this information. APPROACH TO REVIEWING THE GUIDELINES IOM staff reviewed the clinical guidelines listed in the ACC/AHA let- ter and, in addition, the guidelines for valvular heart disease. The clinical guidelines for the diagnosis and management of heart failure in adults had been updated in 2009; they were reviewed in this analysis instead of the earlier one cited in the ACC/AHA letter. The first step was to search each guideline for any mention of the impact of the heart condition or its treatment on a person’s capacity to engage in gainful activity, using terms such as employment, return to work, or work capacity. An electronic copy was scanned for the following terms:

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 aPPEndIx C BOX C-1 American College of Cardiology/American Heart Association (ACC/AHA) Guidelines Heart Failure 2009 Focused Update Incorporated into the ACC/AHA 2005 Guidelines for the Diagnosis and Management of Heart Failure in Adults: A Report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines Note: Updated  version  of  the  guideline  cited  in  the  appendix  to  the  June  2008  ACC/AHA response letter to the Social Security Administration Advance Notice  of Proposed Rulemaking. Ischemic Heart Disease 2002 Guideline Update for the Management of Patients with Chronic Stable An- gina: A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee to Update the 1999 Guidelines for the Management of Patients with Chronic Stable Angina) 2007 Chronic Angina Focused Update of the ACC/AHA 2002 Guidelines for the Management of Patients with Chronic Stable Angina: A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guide- lines Writing Group to Develop the Focused Update of the 2002 Guidelines for the Management of Patients with Chronic Stable Angina Note:  Only  recommendations  related  to  secondary  prevention  in  patients  with  chronic angina were revised. Peripheral Arterial Disease ACC/AHA 2005 Guidelines for the Management of Patients with Peripheral Arte- rial Disease (Lower Extremity, Renal, Mesenteric, and Abdominal Aortic): A Col- laborative Report from the American Association for Vascular Surgery/Society for Vascular Surgery, Society for Cardiovascular Angiography and Interventions, So- ciety for Vascular Medicine and Biology, Society of Interventional Radiology, and the ACC/AHA Task Force on Practice Guidelines (Writing Committee to Develop Guidelines for the Management of Patients with Peripheral Arterial Disease) 2010 ACCF/AHA/AATS/ACR/ASA/SCA/SCAI/SIR/STS/SVM Guidelines for the Diagnosis and Management of Patients with Thoracic Aortic Disease: A Report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines, American Association for Thoracic Surgery, Ameri- can College of Radiology, American Stroke Association, Society of Cardiovascular Anesthesiologists, Society for Cardiovascular Angiography and Interventions, Society of Interventional Radiology, Society of Thoracic Surgeons, and Society for Vascular Medicine Note: This  is  relevant  to  the  committee’s  work,  although  it  is  not  cited  in  the  ACC/AHA letter. continued

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  CaRdIoVaSCUlaR dISabIlIty BOX C-1 Continued Congenital Heart Disease ACC/AHA 2008 Guidelines for the Management of Adults with Congenital Heart Disease: A Report of the American College of Cardiology/American Heart Asso- ciation Task Force on Practice Guidelines (Writing Committee to Develop Guide- lines on the Management of Adults with Congenital Heart Disease) Valvular Heart Disease 2008 Focused Update Incorporated into the ACC/AHA 2006 Guidelines for the Management of Patients with Valvular Heart Disease: A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guide- lines (Writing Committee to Revise the 1998 Guidelines for the Management of Patients with Valvular Heart Disease) Note: This  is  relevant  to  the  committee’s  work,  although  it  is  not  cited  in  the  ACC/AHA letter. Arrhythmias ACC/AHA/ESC 2006 Guidelines for the Management of Patients with Atrial Fibril- lation: A Report of the American College of Cardiology/American Heart Associa- tion Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Revise the 2001 Guide- lines for the Management of Patients with Atrial Fibrillation) ACC/AHA/ESC Guidelines for the Management of Patients with Supraventricular Arrhythmias: A Report of the American College of Cardiology/American Heart Association Task Force and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Develop Guidelines for the Manage- ment of Patients with Supraventricular Arrhythmias) Note: Issued in 2003. ACC/AHA/ESC 2006 Guidelines for Management of Patients with Ventricular Ar- rhythmias and the Prevention of Sudden Cardiac Death: A Report of the American College of Cardiology/American Heart Association Task Force and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Develop Guidelines for Management of Patients with Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death), Developed in Collaboration with the European Heart Rhythm Association and the Heart Rhythm Society (HRS) ACC/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities: Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the ACC/AHA/NASPE [North American Society of Pacing and Electrophysiol- ogy] 2002 Guideline Update for Implantation of Cardiac Pacemakers and Antiar- rhythmia Devices), Developed in Collaboration with the American Association for Thoracic Surgery and Society of Thoracic Surgeons

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 aPPEndIx C Exercise Testing ACC/AHA 2002 Guideline Update for Exercise Testing: A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guide- lines (Committee on Exercise Testing) Echocardiography ACC/AHA/ASE (American Society of Echocardiography) 2003 Guideline Update for the Clinical Application of Echocardiography: A Report of the American Col- lege of Cardiology/American Heart Association Task Force on Practice Guidelines (ACC/AHA/ASE Committee to Update the 1997 Guidelines for the Clinical Ap- plication of Echocardiography) • Work (e.g., working, worked, worker); • Occupation (e.g., occupations, occupational); • Employ (e.g., employment, employed, employability, employee, employer); • Unemploy (e.g., unemployment, unemployed); • Vocation (e.g., vocation, vocational); • Job; • Economic; and • Gainful activity. Each time one of these words appeared in the text of the clinical guide- line, the paragraph in which it appeared was examined to see if and how it referred to the patient situation. The main objective was to see whether any diagnostic or treatment criterion, such as a laboratory test result, an examination finding, a clinical severity score, or a treatment, was associ- ated in the clinical guideline with the existence or severity of employment disability. The second step was to search each clinical guideline for any mention of the disabling effects of the heart condition or its treatment other than on employment. An electronic copy was scanned for the following words: • Disab (e.g., disability, disabled, disablement); • Functional capacity; • Functional limitation; and • Functional status.

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4 4 CaRdIoVaSCUlaR dISabIlIty RESULTS1 If any of these words appeared in the text of the clinical guideline, the paragraph in which it appeared was examined to see if and how it referred to the patient situation. For example, if the word impairment was used, did it refer to organ function or whole-person function? The main objective was to see if any diagnostic or treatment criteria (e.g., laboratory test results, exami- nation findings, clinical severity scores, or treatment regimens) were associated with the existence or severity of disability or whole-person impairment. The Guidelines and Disability Generally, the guidelines contain little information relevant to develop- ing criteria for evaluating degree of disability. They are focused on decision making regarding diagnosis and treatment. None of the guidelines ad- dressed patient disability, employment, or employability as a major topic of discussion. For example, none had a heading or subheading for disability or employment. They rarely indicate the relationship of impairment sever- ity to employment restrictions or even to functional limitations that might affect work capacity. Most frequently, references to disability were in the context of general assertions that the condition in question is a cause of disability, functional limitations, and lower quality of life. For example, the heart failure guidelines say heart failure is a “common, costly, disabling, and potentially fatal disorder” (Hunt et al., 2009:e395). Those guidelines go on to say that dyspnea and fatigue, the “cardinal manifestations” of heart failure, may lead to pulmonary congestion and peripheral edema, abnormalities that can reduce functional capacity and quality of life (Hunt et al., 2009:e397). Sometimes, there are statements that a specific examination or test would be useful for determining disability but not how. For example, The primary value of exercise testing in valvular heart disease is to ob- jectively assess atypical symptoms, exercise capacity, evaluation of LV function during exercise with imaging modalities, and extent of disability, which may have implications for medical, surgical, and social decision making. (Gibbons et al., 2002:40) Several of the guidelines note that clinical findings, such as hemody- namic variables, that they recommend for diagnostic and prognostic pur- poses are not strongly associated with degree of functional limitation. 1 A complete set of references to disability, employment or work, and functional capacity, limitation, or status in the ACC/AHA guidelines is included in a supplementary online table available at http://www.iom.edu/ssacardiodisability.

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 aPPEndIx C Patients with a very low EF [ejection fraction] . . . may be asymptomatic, whereas patients with preserved [i.e., normal or near normal] LVEF [left ventricular ejection fraction] may have severe disability. The apparent dis- cordance between EF and the degree of functional impairment is not well understood. . . . (Hunt et al., 2009:e397) The ABI [ankle-brachial index] correlates only weakly with treadmill- based walking ability for any individual patient. For example, some pa- tients with a low ABI report minimal walking impairment, whereas some with a higher ABI report marked walking impairment. This is due at least in part to the wide range of comorbidities that can coexist with intermit- tent claudication in patients who have PAD [peripheral artery disease]. (Hirsch et al., 2006:e481) Even if the guidelines placed more emphasis on disability, little available research correlates degree of impairment severity with disability outcomes, such as the relationship of different percentages of ejection fraction and employment capacity or activity limitations for individuals with heart failure. Most clinical trials look at clinical outcomes, such as mortality, recurrence, and rehospitalizations, and patient registries usually track the same outcomes. The small number of trials that have collected and reported data on employment, such as return to work after myocardial infarction or angioplasty, have found that clinical variables explain only part of the employment-related outcome; these trials did not collect information on the range of nonclinical variables that are needed to explain the employment- related outcome completely. Thus, for example, the guidelines for the management of Patients with Chronic Stable angina note the finding in the Bypass Angioplasty Revascularization Investigation study that about 30 percent of patients who undergo angioplasty never return to work, but they do not provide guidance on how to predict which patients will not return to work because they are incapacitated by their coronary heart disease rather than for other reasons (Gibbons et al., 2002). Some guidelines provide guidance on effective rehabilitation techniques. Effectiveness is generally based on degree of improvement in functional capacity (see next section). None are based specifically on work-related outcomes. The Guidelines and Functional Capacity Most of the guidelines discuss assessment of function, usually through treadmill or bicycle exercise tests or, for more disabled patients, the 6- minute walk test. A few make the statement that such tests, such as capacity to walk, are useful for evaluating disability, but none provide guidance on how specific test results predict work capacity.

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  CaRdIoVaSCUlaR dISabIlIty The guidelines also endorse the New York Heart Association (NYHA) functional classification of symptom severity, widely used to gauge degree of functional limitation from heart failure, and the Canadian Cardiovascular Society (CCS) classification of symptoms and physical limitations from angina, used in the evaluation and treatment of ischemic heart disease. Each classification system has four classes based on the degree of exertion required to elicit symptoms, from no symptoms during ordinary activity (Class 1) to symptoms from any exertion or even at rest (Class 4). The patient’s NYHA class is the basis for a number of diagnosis and treatment recommendations in the heart failure guidelines. CCS class is similarly used in the guidelines for management and follow-up of patients with chronic stable angina. NYHA functional class is also a criterion for some indications in the valvular heart disease guidelines (e.g., aortic valve repair, mitral balloon valvotomy, mitral valve repair and replacement) (Bonow et al., 2008). NYHA Class II or III is indicated for implantable cardioverter- defibrillator therapy in the guidelines on ventricular arrhythmias (Class I Recommendation, Level of Evidence: A) and for other indications (Zipes et al., 2006). The Guidelines and Activity Limitations The heart failure guidelines say that physical activity should be encour- aged in patients with current or prior symptoms of heart failure to avoid de- conditioning and exercise intolerance, “although most patients should not participate in heavy labor or exhaustive sports” (Hunt et al., 2009:e412). Guidelines for chronic stable angina similarly encourage normal physical activity, although “patients in special circumstances, for example, those who engage in extremely strenuous activity or have a high-risk occupation, may require special counseling” (Gibbons et al., 2002:63). Patients on anticoagulants should be advised of activity restrictions, according to the valvular heart disease guidelines. The same guidelines recommend restrictions on participating in competitive sports for patients with symptomatic mitral valve prolapse and certain signs (e.g., moderate left ventricular [LV] enlargement, LV dysfunction, uncontrolled tachyar- rhythmias, long-QT interval, unexplained syncope, prior resuscitation from cardiac arrest, or aortic root enlargement is present individually or in com- bination). Patients with mitral regurgitation “with definite LV enlargement (greater than or equal to 60 mm), pulmonary hypertension, or any degree of LV systolic dysfunction at rest should not participate in any competitive sports” (Bonow et al., 2008:e59). The guidelines on management of patients with peripheral artery dis- ease contained no activity restrictions (Hirsch et al., 2006). Guidelines for adult congenital heart disease contain a guidance on physical activ-

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 aPPEndIx C ity and exercise for patients with each type of congenital condition (e.g., atrial septal defect, ventricular septal defect, atrioventricular septal defect, dextro-transposition of the great arteries, tetralogy of Fallot) (Warnes et al., 2008). Guidelines for the diagnosis and management of patients with thoracic aortic disease include a recommendation regarding limitations on employment and lifestyle in patients with thoracic aortic disease (but based on scanty data): For patients with a current thoracic aortic aneurysm or dissection, or previously repaired aortic dissection, employment and lifestyle restrictions are reasonable, including the avoidance of strenuous lifting, pushing, or straining that would require a Valsalva maneuver (Class IIa, Recommenda- tion Level of Evidence: C). (Hiratzka et al., 2010:e344) The thoracic aortic disease guidelines go on to explain more about work: In terms of work, patients with thoracic aortic disease generally can function normally in most types of occupations. The exception is any job involving heavy physical and manual labor accompanied by extreme iso- metric exercise (e.g., lifting heavy boxes in a stockroom, carrying furniture up and down stairs). As with the heavy weight lifting described earlier, this type of unusual sudden stress on the aorta may predispose to a trigger- ing of either aortic rupture or AoD [aortic dissection]. Therefore, when patients have a vocation in which such extreme lifting might be required, it is important to discuss the details of their daily job responsibilities and to prescribe avoidance of activities that might put them at risk. In some cases patients can readily avoid such heavy lifting on the job, but in many cases a letter from a physician explaining the restrictions may be required. (Hiratzka et al., 2010) REFERENCES Bonow, R. O., B. A. Carabello, K. Chatterjee, A. C. de Leon Jr., D. P. Faxon, M. D. Freed, W. H. Gaasch, B. W. Lytle, R. A. Nishimura, P. T. O’Gara, R. A. O’Rourke, C. M. Otto, P. M. Shah, and J. S. Shanewise. 2008. 2008 focused update incorporated into the ACC/AHA 2006 guidelines for the management of patients with valvular heart dis- ease: A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 1998 Guidelines for the Management of Patients with Valvular Heart Disease). Journal of the american College of Cardiology 52(13):e1–e142. http://www.heartj.com/GuideLines/Valvular%20Heart% 20Disease.pdf (accessed August 3, 2010). Gibbons, R. J., J. Abrams, K. Chatterjee, J. Daley, P. C. Deedwania, J. S. Douglas, T. B. Ferguson Jr., S. D. Fihn, T. D. Fraker Jr., J. M. Gardin, R. A. O’Rourke, R. C. Pasternak, and S. V. Williams. 2002. ACC/AHA 2002 guideline update for the management of patients with chronic stable angina: A report of the American College of Cardiology/ American Heart Association Task Force on Practice Guidelines (Committee to Update the 1999 Guidelines for the Management of Patients with Chronic Stable Angina).

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