American College of Cardiology

GIBBONS ET AL., MANAGEMENT OF PATIENTS WITH CHRONIC STABLE ANGINA UPDATE
http://www.acc.org/clinical/guidelines/stable/update_index.htm

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)

This is a Guideline Update of the 1999 Chronic Stable Angina Guidelines. To highlight the changes, deleted text is indicated by strikeout, and revised text is presented in brown. A clean version of the document, with changes fully incorporated, is available for download and print.

V. PATIENT FOLLOW-UP: MONITORING OF SYMPTOMS AND ANTIANGINAL THERAPY

A. Pharmacologic Therapy

Recommendations for Echocardiography, Treadmill Exercise Testing, Stress Radionuclide Imaging, Stress Echocardiography Studies, and Coronary Angiography During Patient Follow-up

Class I

1. Chest X-ray for patients with evidence of new or worsening CHF. (Level of Evidence: C)

2. Assessment of LV ejection fraction and segmental wall motion by echocardiography or radionuclide imaging in patients with new or worsening CHF or evidence of intervening MI by history or ECG. (Level of Evidence: C)

3. Echocardiography for evidence of new or worsening valvular heart disease. (Level of Evidence: C)

4. Treadmill exercise test for patients without prior revascularization who have a significant change in clinical status, are able to exercise, and do not have any of the ECG abnormalities listed below in number 5. (Level of Evidence: C)

5. Stress radionuclide imaging or stress echocardiography procedures for patients without prior revascularization who have a significant change in clinical status and are unable to exercise or have one of the following ECG abnormalities:

a. Pre-excitation (Wolff-Parkinson-White) syndrome. (Level of Evidence: C)

b. Electronically paced ventricular rhythm. (Level of Evidence: C)

c. More than 1 mm of rest ST depression. (Level of Evidence: C)

d. Complete left bundle-branch block. (Level of Evidence: C)

6. Stress radionuclide imaging or stress echocardiography procedures for patients who have a significant change in clinical status and required a stress imaging procedure on their initial evaluation because of equivocal or intermediate-risk treadmill results. (Level of Evidence: C)

7. Stress radionuclide imaging or stress echocardiography procedures for patients with prior revascularization who have a significant change in clinical status. (Level of Evidence: C)

8. Coronary angiography in patients with marked limitation of ordinary activity (CCS class III) despite maximal medical therapy. (Level of Evidence: C)

Class IIb

Annual treadmill exercise testing in patients who have no change in clinical status, can exercise, have none of the ECG abnormalities listed in number 5, and have an estimated annual mortality rate greater than 1%. (Level of Evidence: C)

Class III

1. Echocardiography or radionuclide imaging for assessment of LV ejection fraction and segmental wall motion in patients with a normal ECG, no history of MI, and no evidence of CHF. (Level of Evidence: C)

2. Repeat treadmill exercise testing in less than three years in patients who have no change in clinical status and an estimated annual mortality rate less than 1% on their initial evaluation, as demonstrated by one of the following:

a. Low-risk Duke treadmill score (without imaging). (Level of Evidence: C)

b. Low-risk Duke treadmill score with negative imaging. (Level of Evidence: C)

c. Normal LV function and a normal coronary angiogram. (Level of Evidence: C)

d. Normal LV function and insignificant CAD. (Level of Evidence: C)

3. Stress imaging or echocardiography procedures for patients who have no change in clinical status and a normal rest ECG, are not taking digoxin, are able to exercise, and did not require a stress imaging or echocardiographic procedure on their initial evaluation because of equivocal or intermediate-risk treadmill results. (Level of Evidence: C)

4. Repeat coronary angiography in patients with no change in clinical status, no change on repeat exercise testing or stress imaging, and insignificant CAD on initial evaluation. (Level of Evidence: C)

Patients Not Addressed by This Section of the Guidelines and Level of Evidence for Recommendations for Follow-up

A. Patients Not Addressed in This Section of the Guidelines

1. Follow-up of Patients in the Following Categories Is not Addressed by This Section of the Guidelines:

• Patients who have had an MI without subsequent symptoms. These patients should be evaluated according to the acute MI guidelines (1,892).

• Patients who have had an acute MI and develop chest pain within 30 days of the acute MI should be evaluated according to the acute MI guidelines (1,892).

• Patients who have had an MI who develop stable angina more than 30 days after infarction. These patients should have the initial assessment and therapy recommended for all patients.

• Patients who have had revascularization with angioplasty or CABG without subsequent symptoms. These patients should be monitored according to guidelines provided elsewhere (18,19,1032,1033).

• Patients who have had angioplasty or CABG and develop angina within six months of revascularization should be monitored according to the PCI and CABG guidelines (18,19,1032,1033).

2. Level of Evidence for Recommendations on Follow-up of Patients With Chronic Stable Angina

Although evidence of the influence of antiplatelet therapy, anti-ischemic therapy, revascularization, and risk factor reduction on health status outcome in patients with chronic stable angina exists, published evidence of the efficacy of specific strategies for the follow-up of patients with chronic stable angina on patient outcome does not. The recommendations in this section of the guidelines are therefore based on the consensus of the committee rather than published evidence.

Questions to Be Addressed in Follow-up of Patients With Chronic Stable Angina

There are five questions that must be answered regularly during the follow-up of the patient who is receiving treatment for chronic stable angina:

1. Has the patient decreased his or her level of physical activity since the last visit?

2. Have the patient’s anginal symptoms increased in frequency and become more severe since the last visit? If the symptoms have worsened or the patient as decreased his or her physical activity to avoid precipitating angina, then he or she should be evaluated and treated appropriately according to either the unstable angina (2,893) or chronic stable angina guideline.

3. How well is the patient tolerating therapy?

4. How successful has the patient been in modifying risk factors and improving knowledge about ischemic heart disease?

5. Has the patient developed any new comorbid illnesses, or has the severity or treatment of known comorbid illnesses worsened the patient’s angina?

Follow-up: Frequency and Methods

The committee believes that the patient with successfully treated chronic stable angina should have a follow-up evaluation every 4 to 12 months. A more precise interval cannot be recommended because many factors influence the length of the follow-up period. During the first year of therapy, evaluations every four to six months are recommended. After the first year of therapy, annual evaluations are recommended if the patient is stable and reliable enough to call or make an appointment when anginal symptoms become worse or other symptoms occur. Patients who are comanaged by their primary-care physician and cardiologists may alternate these visits, provided that communication among physicians is excellent and all appropriate issues are addressed at each visit. Annual office visits can be supplemented by telephone or other types of contact between the patient and the physicians caring for him or her. Patients who cannot reliably identify and report changes in their status or who need more support with their treatment or risk factor reduction should be seen more frequently.

Focused Follow-up Visit: History

GENERAL STATUS AND NEW CONCERNS. The open-ended question “How are you doing?” is recommended because it reveals many important issues. A general assessment of the patient’s functional status and health-related quality of life may reveal additional issues that affect angina. For example, loss of weight may indicate depression or hyperthyroidism. Angina may be exacerbated by a personal financial crisis that prevents the patient from refilling prescriptions for medications. Open-ended questions should be followed by specific questions about the frequency, severity, and quality of angina. Symptoms that have worsened should prompt reevaluation as outlined in these guidelines. A detailed history of the patient’s level of activity is critical, because anginal symptoms may remain stable only because stressful activities have been eliminated. If the patient’s account is not reliable, the assessment of a spouse, other family members, or friends needs to be included.

ANGINAL SYMPTOMS AND ANTIANGINAL AND ANTIPLATELET THERAPY. A careful history of the characteristics of the patient’s angina, including exacerbating and alleviating conditions (outlined in Section II.A), must be repeated at each visit. Detailed questions should be asked about common drug side effects. An assessment should be made of the patient’s adherence to the treatment program. Special emphasis should be given to aspirin because of its effectiveness, low cost, and minimal side effects. Providing a written prescription may help patients follow the recommendation for aspirin therapy. MODIFIABLE RISK FACTORS. Each patient should be asked specific questions about his or her modifiable risk factors (Section IV.C).

REVIEW OF EXISTING COMORBID ILLNESSES THAT MAY INFLUENCE CHRONIC STABLE ANGINA. Specific questions should be asked about exacerbating illnesses and conditions (Section II.B). The elderly deserve extra attention, especially with regard to a drug’s side effects and the impact of polypharmacy.

Focused Follow-up Visit: Physical Examination

The physical examination should be determined by the patient’s history. Every patient should have weight, blood pressure, and pulse noted. Jugular venous pressure and wave form, carotid pulse magnitude and upstroke, and the presence or absence of carotid bruits should be noted. Pulmonary examination, with special attention to rales, rhonchi, wheezing, and decreased breath sounds, is required. The cardiac examination should note the presence of gallops, a new or changed murmur, the location of the apical impulse, and any change from previous examinations. The vascular examination should identify any change in peripheral pulses and new bruits. The abdominal examination should identify hepatomegaly, hepatojugular reflux, and the presence of any pulsatile masses suggestive of abdominal aortic aneurysm. The presence of new or worsening peripheral edema should be noted.

Laboratory Examination on Follow-up Visits

GLUCOSE. The committee supports the current American Diabetes Association recommendation to screen patients not known to have diabetes with a fasting blood glucose measurement every three years and annual measurement of glycosylated hemoglobin for persons with established diabetes (740).

CHOLESTEROL. The committee supports the National Cholesterol Education Program ATP III guidelines, which recommend follow-up fasting blood work six to eight weeks after initiation of lipid-lowering drug therapy, including liver function testing and assessment of the cholesterol profile, and then periodically every 8 to 12 weeks during the first year of therapy. Subsequent cholesterol measurements at four- to six-month intervals are recommended. Long-term studies (up to seven years) demonstrate sustained benefit from continued therapy.

LABORATORY ASSESSMENT FOR NONCARDIAC COMORBID CONDITIONS. Routine measurement of hemoglobin, thyroid function, serum electrolytes, renal function, or oxygen saturation is not recommended. These tests should be obtained when required by the patient’s history, physical examination, or clinical course.

ECG AND FOLLOW-UP STRESS TESTING. The ECG can be repeated when medications affecting cardiac conduction are initiated or changed. A repeat ECG is indicated for a change in the anginal pattern, symptoms or findings suggestive of a dysrhythmia or conduction abnormality, and near or frank syncope. There is no clear evidence showing that routine, periodic ECGs are useful in the absence of a change in history or physical examination.

Despite widespread use of follow-up stress testing in patients with stable angina, there are very few published data establishing its utility. The natural history of various patient cohorts with stable angina is well documented, and using the rationale described above, the committee formulated the following guidelines by expert consensus. On the basis of the clinical, noninvasive, and invasive data acquired during the initial evaluation, the clinician should be able to formulate an estimate of the patient’s cardiovascular risk over the next three years. In the absence of a change in clinical status, low-risk patients with an estimated annual mortality rate of less than 1% over each year of the interval do not require repeat stress testing for three years after the initial evaluation. Examples of such patients are those with low-risk Duke treadmill scores either without imaging or with negative imaging (four-year cardiovascular survival rate, 99%), those with normal LV function and normal coronary angiograms, and those with normal LV function and insignificant CAD. The first group includes patients with chest pain more than six months after coronary angioplasty who have undergone complete revascularization and who do not have significant restenosis as demonstrated by angiography. Annual follow-up testing in the absence of a change in symptoms has not been adequately studied; it might be useful in high-risk patients with an estimated annual mortality rate greater than 3%. Examples of such patients include those with an ejection fraction less than 50% and significant CAD in more than one major vessel and those with treated diabetes and multivessel CAD who have not undergone CABG. Follow-up testing should be performed in a stable high-risk patient only if the initial decision not to proceed with revascularization may change if the patient’s estimated risk worsens. Patients with an intermediate-risk (greater than 1% and less than 3%) annual mortality rate are more problematic on the basis of the limited data available. They may merit testing at an interval of one to three years, depending on their individual circumstances.

The choice of stress test to be used in patient follow-up testing should be dictated by considerations similar to those outlined earlier for the initial evaluation of the patient. In patients with interpretable exercise ECGs who are capable of exercise, treadmill exercise testing remains the first choice. Whenever possible, follow-up testing should be done using the same stress and imaging techniques to permit the most valid comparison with the original study. When different modes of stress and imaging are used, it is much more difficult to judge whether an apparent change in results is due to differences in the modality or a change in the patient’s underlying status. In a patient who was able to exercise on the initial evaluation, the inability to exercise for follow-up testing is in and of itself a worrisome feature that suggests a definite change in functional and clinical status. In interpreting the results of follow-up testing, the physician must recognize that there is inherent variability in the tests that does not necessarily reflect a change in the patient’s prognosis. For exam-ple, in one placebo-controlled trial that used serial exercise thallium testing, the treadmill time on repeat testing in the placebo group had a standard deviation of 1.3 min and the measured thallium perfusion defect of the LV a standard deviation of about 5% (891). Both estimates suggest that even one standard deviation (67% confidence limits) on repeat testing includes a considerable range of results.