The American College of Cardiology/American Heart Association (ACC/AHA) classification of the recommendations for patient evaluation and treatment (classes I-III) and the levels of evidence (A-C) are defined at the end of the Major Recommendations field.
General Approach to the Patient
Table: Active Cardiac Conditions for Which the Patient Should Undergo Evaluation and Treatment Before Noncardiac Surgery (Class I, Level of Evidence: B) |
Condition |
Examples |
Unstable coronary syndromes |
Unstable or severe angina* (Canadian Cardiovascular Society [CCS] class III or IV)**
Recent myocardial infarction (MI)***
|
Decompensated heart failure (HF) (New York Heart Association [NYHA] functional class IV; worsening or new-onset HF) |
|
Significant arrhythmias |
High-grade atrioventricular block
Mobitz II atrioventricular block
Third-degree atrioventricular heart block
Symptomatic ventricular arrhythmias
Supraventricular arrhythmias (including atrial fibrillation) with uncontrolled ventricular rate (heart rate [HR] greater than 100 beats per minute at rest)
Symptomatic bradycardia
Newly recognized ventricular tachycardia
|
Severe valvular disease |
Severe aortic stenosis (mean pressure gradient greater than 40 mm Hg, aortic valve area less than 1.0 cm2, or symptomatic)
Symptomatic mitral stenosis (progressive dyspnea on exertion, exertional presyncope, or HF)
|
|
*According to Campeau (Campeau L. Letter: grading of angina pectoris. Circulation 1976;54:522-3).
**May include "stable" angina in patients who are unusually sedentary.
***The American College of Cardiology National Database Library defines recent MI as more than 7 days but less than or equal to 1 month (within 30 days).
Supplemental Preoperative Evaluation
Assessment of Left Ventricular (LV) Function
Recommendations for Preoperative Noninvasive Evaluation of Left Ventricular Function
Class IIa
- It is reasonable for patients with dyspnea of unknown origin to undergo preoperative evaluation of left ventricular (LV) function. (Level of Evidence: C)
- It is reasonable for patients with current or prior heart failure with worsening dyspnea or other change in clinical status to undergo preoperative evaluation of LV function if not performed within 12 months. (Level of Evidence: C)
Class IIb
- Reassessment of LV function in clinically stable patients with previously documented cardiomyopathy is not well established. (Level of Evidence: C)
Class III
- Routine perioperative evaluation of LV function in patients is not recommended. (Level of Evidence: B)
Assessment of Risk for Coronary Artery Disease (CAD) and Assessment of Functional Capacity
Recommendations for Preoperative Resting 12-Lead Electrocardiogram (ECG)
Class I
- Preoperative resting 12-lead ECG is recommended for patients with at least 1 clinical risk factor* who are undergoing vascular surgical procedures. (Level of Evidence: B)
*Clinical risk factors include history of ischemic heart disease, history of compensated or prior heart failure, history of cerebrovascular disease, diabetes mellitus, and renal insufficiency.
- Preoperative resting 12-lead ECG is recommended for patients with known coronary heart disease, peripheral arterial disease, or cerebrovascular disease who are undergoing intermediate-risk surgical procedures. (Level of Evidence: C)
Class IIa
- Preoperative resting 12-lead ECG is reasonable in persons with no clinical risk factors who are undergoing vascular surgical procedures. (Level of Evidence: B)
Class IIb
- Preoperative resting 12-lead ECG may be reasonable in patients with at least 1 clinical risk factor who are undergoing intermediate-risk operative procedures. (Level of Evidence: B)
Class III
- Preoperative and postoperative resting 12-lead ECGs are not indicated in asymptomatic persons undergoing low-risk surgical procedures. (Level of Evidence: B)
Recommendations for Noninvasive Stress Testing Before Noncardiac Surgery
Class I
- Patients with active cardiac conditions (see the Table above) in whom noncardiac surgery is planned should be evaluated and treated per American College of Cardiology/American Heart Association (ACC/AHA) guidelines (see the original guideline document for the list of guidelines) before noncardiac surgery. (Level of Evidence: B)
Class IIa
- Noninvasive stress testing of patients with 3 or more clinical risk factors and poor functional capacity (less than 4 metabolic equivalents [METs]) who require vascular surgery (i.e., aortic and other major vascular and peripheral vascular surgery) is reasonable if it will change management. (Level of Evidence: B)
Class IIb
- Noninvasive stress testing may be considered for patients with at least 1 to 2 clinical risk factors and poor functional capacity (less than 4 METs) who require intermediate-risk noncardiac surgery if it will change management. (Level of Evidence: B)
- Noninvasive stress testing may be considered for patients with at least 1 to 2 clinical risk factors and good functional capacity (greater than or equal to 4 METs) who are undergoing vascular surgery. (Level of Evidence: B)
Class III
- Noninvasive testing is not useful for patients with no clinical risk factors undergoing intermediate-risk noncardiac surgery. (Level of Evidence: C)
- Noninvasive testing is not useful for patients undergoing low-risk noncardiac surgery. (Level of Evidence: C)
Perioperative Therapy
Preoperative Coronary Revascularization With Coronary Artery Bypass Grafting (CABG) or Percutaneous Coronary Intervention
(All of the Class I indications below are consistent with the ACC/AHA 2004 Guideline Update for Coronary Artery Bypass Graft Surgery.)
Class I
- Coronary revascularization before noncardiac surgery is useful in patients with stable angina who have significant left main coronary artery stenosis. (Level of Evidence: A)
- Coronary revascularization before noncardiac surgery is useful in patients with stable angina who have 3-vessel disease. (Survival benefit is greater when left ventricular ejection fraction is less than 0.50.) (Level of Evidence: A
- Coronary revascularization before noncardiac surgery is useful in patients with stable angina who have 2-vessel disease with significant proximal left anterior descending stenosis and either ejection fraction less than 0.50 or demonstrable ischemia on noninvasive testing. (Level of Evidence: A)
- Coronary revascularization before noncardiac surgery is recommended for patients with high-risk unstable angina or non–ST-segment elevation myocardial infarction (MI).* (Level of Evidence: A)
*High-risk unstable angina/non–ST-elevation MI patients were identified as those with age greater than 75 years, accelerating tempo of ischemic symptoms in the preceding 48 hours, ongoing rest pain greater than 20 minutes in duration, pulmonary edema, angina with S3 gallop or rales, new or worsening mitral regurgitation murmur, hypotension, bradycardia, tachycardia, dynamic ST-segment change greater than or equal to 1 mm, new or presumed new bundle-branch block on ECG, or elevated cardiac biomarkers, such as troponin.
- Coronary revascularization before noncardiac surgery is recommended in patients with acute ST-elevation MI. (Level of Evidence: A)
Class IIa
- In patients in whom coronary revascularization with percutaneous coronary intervention (PCI) is appropriate for mitigation of cardiac symptoms and who need elective noncardiac surgery in the subsequent 12 months, a strategy of balloon angioplasty or bare-metal stent placement followed by 4 to 6 weeks of dual-antiplatelet therapy is probably indicated. (Level of Evidence: B)
- In patients who have received drug-eluting coronary stents and who must undergo urgent surgical procedures that mandate the discontinuation of thienopyridine therapy, it is reasonable to continue aspirin if at all possible and restart the thienopyridine as soon as possible. (Level of Evidence: C)
Class IIb
- The usefulness of preoperative coronary revascularization is not well established in high-risk ischemic patients (e.g., abnormal dobutamine stress echocardiogram with at least 5 segments of wall-motion abnormalities). (Level of Evidence: C)
- The usefulness of preoperative coronary revascularization is not well established for low-risk ischemic patients with an abnormal dobutamine stress echocardiogram (segments 1 to 4). (Level of Evidence: B)
Class III
- It is not recommended that routine prophylactic coronary revascularization be performed in patients with stable CAD before noncardiac surgery. (Level of Evidence: B)
- Elective noncardiac surgery is not recommended within 4 to 6 weeks of bare-metal coronary stent implantation or within 12 months of drug-eluting coronary stent implantation in patients in whom thienopyridine therapy or aspirin and thienopyridine therapy will need to be discontinued perioperatively. (Level of Evidence: B)
- Elective noncardiac surgery is not recommended within 4 weeks of coronary revascularization with balloon angioplasty. (Level of Evidence: B)
Perioperative Medical Therapy
Recommendations for Beta-Blocker Medical Therapy
Care should be taken in applying recommendations on beta-blocker therapy to patients with decompensated heart failure, nonischemic cardiomyopathy, or severe valvular heart disease in the absence of coronary heart disease.
Class I
- Beta blockers should be continued in patients undergoing surgery who are receiving beta blockers to treat angina, symptomatic arrhythmias, hypertension, or other ACC/AHA Class I guideline indications. (Level of Evidence: C)
- Beta blockers should be given to patients undergoing vascular surgery who are at high cardiac risk owing to the finding of ischemia on preoperative testing. (Level of Evidence: B)
Class IIa
- Beta blockers are probably recommended for patients undergoing vascular surgery in whom preoperative assessment identifies coronary heart disease (CHD). (Level of Evidence: B)
- Beta blockers are probably recommended for patients in whom preoperative assessment for vascular surgery identifies high cardiac risk, as defined by the presence of more than 1 clinical risk factor (defined under "Recommendations for Preoperative Resting 12-Lead ECG," above). (Level of Evidence: B)
- Beta blockers are probably recommended for patients in whom preoperative assessment identifies CHD or high cardiac risk, as defined by the presence of more than 1 clinical risk factor (defined under "Recommendations for Preoperative Resting 12-Lead ECG," above), who are undergoing intermediate-risk or vascular surgery. (Level of Evidence: B)
Class IIb
- The usefulness of beta blockers is uncertain for patients who are undergoing either intermediate-risk procedures or vascular surgery, in whom preoperative assessment identifies a single clinical risk factor (defined under "Recommendations for Preoperative Resting 12-Lead ECG," above). (Level of Evidence: C)
- The usefulness of beta blockers is uncertain in patients undergoing vascular surgery with no clinical risk factors who are not currently taking beta blockers. (Level of Evidence: B)
Class III
- Beta blockers should not be given to patients undergoing surgery who have absolute contraindications to beta blockade. (Level of Evidence: C)
Table: Recommendations for Perioperative Beta-Blocker Therapy Based on Published Randomized Clinical Trials
Surgery |
No Clinical Risk Factors |
1 or More Clinical Risk Factors |
CHD or High Cardiac Risk |
Patients Currently Taking Beta Blockers |
Vascular |
Class IIb, Level of Evidence: B |
Class IIa, Level of Evidence: B |
Patients found to have myocardial ischemia on preoperative testing: Class I, Level of Evidence: B*
Patients without ischemia or no previous test: Class IIa, Level of Evidence: B
|
Class I, Level of Evidence: B |
Intermediate risk |
... |
Class IIb, Level of Evidence: C |
Class IIa, Level of Evidence: B |
Class I, Level of Evidence: C |
Low risk |
… |
… |
… |
Class I, Level of Evidence: C |
See Table 4 of the original guideline document for definition of procedures. Ellipses (…) indicate that data were insufficient to determine a class of recommendation or level of evidence. See text for further discussion. CHD indicates coronary heart disease.
*Applies to patients found to have coronary ischemia on preoperative testing
Recommendations for Statin Therapy
Class I
- For patients currently taking statins and scheduled for noncardiac surgery, statins should be continued. (Level of Evidence: B)
Class IIa
- For patients undergoing vascular surgery with or without clinical risk factors, statin use is reasonable. (Level of Evidence: B)
Class IIb
- For patients with at least 1 clinical risk factor who are undergoing intermediate-risk procedures, statins may be considered. (Level of Evidence: C)
Recommendations for Alpha-2 Agonists
Class IIb
- Alpha-2 agonists for perioperative control of hypertension may be considered for patients with known CAD or at least 1 clinical risk factor who are undergoing surgery. (Level of Evidence: B)
Class III
- Alpha-2 agonists should not be given to patients undergoing surgery who have contraindications to this medication. (Level of Evidence: C)
Preoperative Intensive Care Monitoring
Class IIb
- Preoperative intensive care monitoring with a pulmonary artery catheter for optimization of hemodynamic status might be considered; however, it is rarely required and should be restricted to a very small number of highly selected patients whose presentation is unstable and who have multiple comorbid conditions. (Level of Evidence: B)
Anesthetic Considerations and Intraoperative Management
Choice of Anesthetic Technique and Agent
Recommendations for Use of Volatile Anesthetic Agents
Class IIa
- It can be beneficial to use volatile anesthetic agents during noncardiac surgery for the maintenance of general anesthesia in hemodynamically stable patients at risk for myocardial ischemia. (Level of Evidence: B)
Prophylactic Intraoperative Nitroglycerin
Class IIb
- The usefulness of intraoperative nitroglycerin as a prophylactic agent to prevent myocardial ischemia and cardiac morbidity is unclear for high-risk patients undergoing noncardiac surgery, particularly those who have required nitrate therapy to control angina. The recommendation for prophylactic use of nitroglycerin must take into account the anesthetic plan and patient hemodynamics and must recognize that vasodilation and hypovolemia can readily occur during anesthesia and surgery. (Level of Evidence: C)
Use of Transesophageal Echocardiography
Class IIa
- The emergency use of intraoperative or perioperative transesophageal echocardiography is reasonable to determine the cause of an acute, persistent, and life-threatening hemodynamic abnormality. (Level of Evidence: C)
Maintenance of Body Temperature
Class I
- Maintenance of body temperature in a normothermic range is recommended for most procedures other than during periods in which mild hypothermia is intended to provide organ protection (e.g., during high aortic cross-clamping). (Level of Evidence: B)
Perioperative Control of Blood Glucose Concentration
Class IIa
- It is reasonable that blood glucose concentration be controlled* during the perioperative period in patients with diabetes mellitus or acute hyperglycemia who are at high risk for myocardial ischemia or who are undergoing vascular and major noncardiac surgical procedures with planned intensive care unit admission. (Level of Evidence: B)
*Blood glucose levels less than 150 milligrams/deciliter (mg/dL) appear to be beneficial.
Class IIb
- The usefulness of strict control of blood glucose concentration* during the perioperative period is uncertain in patients with diabetes mellitus or acute hyperglycemia who are undergoing noncardiac surgical procedures without planned intensive care unit admission. (Level of Evidence: C)
Perioperative Surveillance
Intraoperative and Postoperative Use of Pulmonary Artery Catheters (PACs)
Recommendations for Perioperative Use of PACs
Class IIb
- Use of a PAC may be reasonable in patients at risk for major hemodynamic disturbances that are easily detected by a PAC; however, the decision must be based on 3 parameters: patient disease, surgical procedure (i.e., intraoperative and postoperative fluid shifts), and practice setting (experience in PAC use and interpretation of results), because incorrect interpretation of the data from a PAC may cause harm. (Level of Evidence: B)
Class III
- Routine use of a PAC perioperatively, especially in patients at low risk of developing hemodynamic disturbances, is not recommended. (Level of Evidence: A)
Intraoperative and Postoperative Use of ST-Segment Monitoring
Class IIa
- Intraoperative and postoperative ST-segment monitoring can be useful to monitor patients with known CAD or those undergoing vascular surgery, with computerized ST-segment analysis, when available, used to detect myocardial ischemia during the perioperative period. (Level of Evidence: B)
Class IIb
- Intraoperative and postoperative ST-segment monitoring may be considered in patients with single or multiple risk factors for CAD who are undergoing noncardiac surgery. (Level of Evidence: B)
Surveillance for Perioperative MI
Class I
- Postoperative troponin measurement is recommended in patients with ECG changes or chest pain typical of acute coronary syndrome. (Level of Evidence: C)
Class IIb
- The use of postoperative troponin measurement is not well established in patients who are clinically stable and have undergone vascular and intermediate-risk surgery. (Level of Evidence: C)
Class III
- Postoperative troponin measurement is not recommended in asymptomatic stable patients who have undergone low-risk surgery. (Level of Evidence: C)
Definitions:
Applying Classification of Recommendations and Level of Evidence
|
SIZE OF TREATMENT EFFECT |
CLASS I
Benefit >>> Risk
Procedure/Treatment SHOULD be performed/ administered
|
CLASS IIa
Benefit >> Risk
Additional studies with focused objectives needed
IT IS REASONABLE to perform procedure/ administer treatment
|
CLASS IIb
Benefit > Risk
Additional studies with broad objectives needed; additional registry data would be helpful
Procedure/Treatment MAY BE CONSIDERED
|
CLASS III
Risk > Benefit
No additional studies needed
Procedure/Treatment should NOT be performed/ administered SINCE IT IS NOT HELPFUL AND MAY BE HARMFUL
|
Estimate of Certainty (Precision) of Treatment Effect |
LEVEL A
Multiple (3–5) population risk strata evaluated*
General consistency of direction and magnitude of effect
|
- Recommendation that procedure or treatment is useful/effective
- Sufficient evidence from multiple randomized trials or meta-analyses
|
- Recommendation in favor of treatment of procedure being useful/effective
- Some conflicting evidence from multiple randomized trials or meta-analyses
|
- Recommendation's usefulness/efficacy less well established
- Greater conflicting evidence from multiple randomized trials or meta-analyses
|
- Recommendation that procedure or treatment is not useful/effective and may be harmful
- Sufficient evidence from multiple randomized trials or meta-analyses
|
LEVEL B
Limited (2–3) population risk strata evaluated*
|
- Recommendation that procedure or treatment is useful/effective
- Limited evidence from single randomized trial or nonrandomized studies
|
- Recommendation in favor of treatment of procedure being useful/effective
- Some conflicting evidence from single randomized trial or nonrandomized studies
|
- Recommendation's usefulness/efficacy less well established
- Greater conflicting evidence from single randomized trial or nonrandomized studies
|
- Recommendation that procedure or treatment is not useful/effective and may be harmful
- Limited evidence from single randomized trial or nonrandomized studies
|
LEVEL C
Very limited (1–2) population risk strata evaluated*
|
- Recommendation that procedure or treatment is useful/effective
- Only expert opinion, case studies, or standard-of-care
|
- Recommendation in favor of treatment of procedure being useful/effective
- Only diverging expert opinion, case studies, or standard-of-care
|
- Recommendation's usefulness/efficacy less well established
- Only diverging expert opinion, case studies, or standard-of-care
|
- Recommendation that procedure or treatment is not useful/effective and may be harmful
- Only expert opinion, case studies, or standard-of-care
|
*Data available from clinical trials or registries about the usefulness/efficacy in different subpopulations, such as gender, age, history of diabetes, history of prior myocardial infarction, history of heart failure, and prior aspirin use. A recommendation with Level of Evidence B or C does not imply that the recommendation is weak. Many important clinical questions addressed in the guidelines do not lend themselves to clinical trials. Even though randomized trials are not available, there may be a very clear clinical consensus that a particular test or therapy is useful or effective.
NOTE: In 2003, the American College of Cardiology/American Heart Association (ACC/AHA) Task Force on Practice Guidelines developed a list of suggested phrases to use when writing recommendations. All guideline recommendations have been written in full sentences that express a complete thought, such that a recommendation, even if separated and presented apart from the rest of the document (including headings above sets of recommendations), would still convey the full intent of the recommendation. It is hoped that this will increase readers' comprehension of the guidelines and will allow queries at the individual recommendation level. (See Table 1 in the original guideline document for a list of suggested phrases for writing recommendations.)