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ACC/AHA Pocket Guidelines for

PerioperativeCardiovascularEvaluation forNoncardiacSurgery(A Report of the American College of Cardiology/

American Heart Association Task Force on Practice Guidelines)

Writing Committee

Kim A. Eagle, MD, FACC (Chair)

Bruce H. Brundage, MD, FACC

Bernard R. Chaitman, MD, FACC

Gordon A. Ewy, MD, FACC

Lee A. Fleisher, MD, FACC

Norman R. Hertzer, MD

Jeffrey A. Leppo, MD, FACC

Thomas Ryan, MD, FACC

Robert C. Schlant, MD, FACC

William H. Spencer III, MD, FACC

John A. Spittell, Jr., MD, FACC

Richard D. Twiss, MD, FACC


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Purpose of These Guidelines

hese guidelines are intended for

physicians involved in the preoperative,operative, and postoperative care of patientsundergoing noncardiac surgery. They providea framework for considering cardiac riskof noncardiac surgery in a variety of patientand operative situations. They strive toincorporate what is currently known aboutperioperative risk and how this knowledgecan be used to treat individual patients. The

methods used to develop these guidelinesare described in the full text of the guide-lines, published in theJournal of the AmericanCollege of Cardiology and Circulation.*

*JACC 1996;27:910-948; Circulation 1996;93:1278-1317.

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Contents

Purpose of These Guidelines . . . . . . . . . . . . . . . . . . . 3

General Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4Preoperative Clinical Evaluation . . . . . . . . . . . . . . . .5

Further Preoperative Testing to

Assess Coronary Risk . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Methods of Assessing Cardiac Risk . . . . . . . . . . . .13

Implications of Risk Assessment

Strategies on Costs . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Management of Specific Preoperative

Cardiovascular Conditions . . . . . . . . . . . . . . . . . . . . 19Preoperative Coronary Revascularization . . . . . . .22

Medical Therapy for

Coronary Artery Disease . . . . . . . . . . . . . . . . . . . . . . 24

Anesthetic Considerations and

Intraoperative Management . . . . . . . . . . . . . . . . . . . 25

Perioperative Surveillance . . . . . . . . . . . . . . . . . . . . . 28

Postoperative Therapy and

Long-Term Management . . . . . . . . . . . . . . . . . . . . . . 31

1997 American College of Cardiology and

American Heart Association, Inc.

The following article was adapted from the ACC/AHA Guidelines for

Perioperative Cardiovascular Evaluation for Noncardiac Surgery (JACC,

Vol. 27, No.4, March 15, 1996, 910-948; and Circulation,Vol. 93,

No.6, March 15, 1996, 1278-1317). For a complimentary reprint of

the full report as published inJACC and Circulation, please contact

ACC Educational Services, 800-253-4636, ext. 694 or visit our web-

sites at www.acc.org or www.amhrt.org.


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General Approach

uccessful perioperative evaluation and

treatment of cardiac patients undergoingnoncardiac surgery requires careful team-work and communication between patient,primary care physician, anesthesiologist,surgeon, and the medical consultant. Ingeneral, indications for further cardiac test-ing and treatments are the same as those inthe nonoperative setting, but their timingis dependent on such factors as the urgency

of noncardiac surgery, the patients riskfactors, and specific surgical considerations.Coronary revascularization before noncardiacsurgery to enable the patient to get throughthe noncardiac procedure is appropriate onlyfor a small subset of patients at very highrisk. Preoperative testing should be limitedto circumstances in which the results willaffect patient treatment and outcomes. A

conservative approach to the use of expen-sive tests and treatments is recommended.

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Preoperative Clinical Evaluation

he initial history, physical examination,

and electrocardiographic (ECG) assess-ment should focus on the identification ofpotentially serious cardiac disorders, includ-ing coronary artery disease (CAD) (eg, priormyocardial infarction [MI], angina pectoris),congestive heart failure (CHF), and electricalinstability (symptomatic arrhythmias).

In addition to identifying thepresence ofpreexisting manifested heart disease, it isessential to define disease severity, stability,and priortreatment. Other factors that helpdetermine cardiac risk include

q functional capacity

q age

q comorbid conditions (eg, diabetesmellitus, peripheral vascular disease, renal

dysfunction, chronic pulmonary disease)

q type of surgery (vascular procedures andprolonged complicated thoracic, abdominal,and head and neck procedures are consid-ered higher risk)

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categories have been established as blackand white, but it is recognized that individ-ual patient problems occur in shades of

gray. The clinician must consider severalinteracting variables and weight them appro-priately. Furthermore, there are no adequatecontrolled or randomized clinical trials tohelp define the process.

The following steps correspond to thealgorithm presented in the Figure (page 32).

What is the urgency of noncardiacsurgery? In many instances, patient or

specific surgical factors dictate an obviousstrategy (ie, immediate surgery) which maynot allow further cardiac evaluation. In suchcases, the consultant may function best bymaking recommendations for perioperativemedical management and surveillance.Postoperative risk stratification may be

appropriate for some patients who havenot had such an assessment.

Has the patient undergone coronaryrevascularization in the past 5 years?

If so, and if clinical status has remainedstable without recurrent symptoms/signs ofischemia, further cardiac testing is generallynot necessary.

Further Preoperative

Testing to Assess Coronary Risk

oronary heart disease is the mostfrequent cause of perioperative cardiac

mortality and morbidity after noncardiacsurgery. A common question concerningnoncardiac surgery is which patients aremost likely to benefit from preoperativecoronary assessment and treatment? Thelack of adequately controlled or randomizedclinical trials to define the optimal evaluation

strategy has led to the proposed algorithmbased on collected observational data andexpert opinion. A step-wise Bayesian strategythat relies on assessment of clinical markers,prior coronary evaluation and treatment,functional capacity, and surgery-specific riskis outlined below and correlates with theinformation in Tables 1-4 and the Figure(page 32), which presents in algorithmicform a framework for determining whichpatients are candidates for cardiac testing.Table 1 outlines clinical predictors of peri-operative risk. Table 2 presents a validatedmethod for assessing functional capacity.Table 3 stratifies risk of various types ofnoncardiac surgeries. Table 4 lists the indica-tions for coronary angiography. For clarity,

Step 1

Step 2

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Does the patient have intermediateclinical predictors of risk (Table 1)? The

presence or absence of prior MI by history

or electrocardiogram, angina pectoris,compensated or prior CHF, and/or diabetesmellitus helps further stratify clinical risk forperioperative coronary events. Considerationoffunctional capacity and level ofsurgery-

specific risk allows a rational approach toidentifying patients most likely to benefitfrom further noninvasive testing.

Functional capacity can be expressed inmetabolic equivalent (MET) levels; theoxygen consumption (VO2) of a 70-kg, 40year-old man in a resting state is 3.5 mL/kgper minute or 1 MET. Multiples of thebaseline MET value can be used to expressaerobic demands for specific activities.Perioperative cardiac and long-term risk isincreased in patients who are unable to meet

a 4-MET demand during most normal dailyactivities. The Duke Activity Status Index(Table 2) and other activity scales providethe clinician with a relatively easy set ofquestions to determine a patients functionalcapacity as less than or greater than 4 METs.

Has the patient had a coronary evalua-tion in the past 2 years? If coronary risk

was adequately assessed and the findings

were favorable, it is usually not necessary torepeat testing unless the patient has experi-enced a change or new symptoms of coro-nary ischemia since the previous evaluation.

Does the patient have an unstablecoronary syndrome or a major clinical

predictor of risk (Table 1)? When electivenoncardiac surgery is being considered, the

presence of unstable coronary disease,decompensated CHF, symptomatic arrhyth-mias, and/or severe valvular heart diseaseusually leads to cancellation or delay ofsurgery until the problem has been identifiedand treated. Examples of unstable coronarysyndromes include recent MI with evidenceof ischemic risk by clinical symptoms ornoninvasive study, unstable or severe angina,

and new or poorly controlled ischemia-medi-ated CHF. Many patients in these circum-stances are referred for coronary angiographyto further assess therapeutic options.

Step 4

Step 5Step 3


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Surgery-specific cardiac risk (Table 3) of non-cardiac surgery is related to two importantfactors. First, the type of surgery itself may

identify a patient with a greater likelihood ofunderlying heart disease, such as in vascularsurgery, where underlying CAD is presentin a substantial portion of patients. A secondaspect is the degree of hemodynamic stressassociated with surgery-specific procedures.Certain operations more predictably result inintraoperative or postoperative alterations inheart rate and blood pressure, fluid shifts,

pain, bleeding, clotting tendencies, oxygena-tion, neurohumoral activation, and otherperturbations. The duration and intensity ofthese coronary and myocardial stressorshelp estimate the likelihood of perioperativecardiac events. This likelihood is particularlyevident for emergency surgery, in which therisk of cardiac complications is substantiallyelevated.

Examples of noncardiac surgery and theirsurgery-specific risks are provided in Table 3.Higher-risk surgery includes aortic surgery,peripheral vascular surgery, and anticipatedprolonged procedures associated with majorfluid shifts and/or blood loss involving theabdomen, thorax, head, and neck.

Patients without major but with inter-mediate predictors of clinical risk

(Table 1) and with moderate or excellent

functional capacity can generally undergointermediate-risk surgery with littlelikelihood of perioperative death or MI.Conversely, further noninvasive testing isoften considered for patients with poor func-tional capacity or moderate functional capac-ity but higher-risk surgery and especially forpatients with two or more intermediate pre-dictors (ie, prior MI, prior or compensated

CHF, angina, or diabetes mellitus).

Noncardiac surgery is generally safe forpatients with neither major nor inter-

mediate predictors of clinical risk (Table 1)and moderate or excellent functional capaci-ty (4 METs or greater). Further testing maybe considered on an individual basis forpatients without clinical markers but poor

functional capacity who are facing higher-riskoperations, particularly those with severalminor clinical predictors of risk who are toundergo vascular surgery.

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Methods of Assessing Cardiac Risk

Resting Left Ventricular Function

everal studies have shown that a leftventricular (LV) ejection fraction below

35% increases risk of noncardiac surgery.Patients with severe diastolic dysfunctionare also at increased risk. The presence ofcurrent or poorly controlled CHF is an indi-cation for evaluation of LV function. Possibleindications include prior CHF or dyspneaof unknown etiology.

Exercise Stress Testing

reoperative exercise testing using tread-mill or bicycle stress and ECG analysis

with or without nuclear myocardial perfu-sion imaging echocardiography to identifyischemia provides substantial informationabout risk of perioperative MI and cardiac

death. Poor functional capacity, particularlythat associated with myocardial ischemia,identifies patients with a severalfoldincreased risk of untoward outcomes. Agradient of increasing ischemic risk is seen

The results of noninvasive testing canbe used to determine further preopera-

tive management. Such management may

include intensified medical therapy; cardiaccatheterization, which may lead to coronaryrevascularization; or cancellation or delayof the elective noncardiac operation. Alterna-tively, the results may lead to a recommen-dation to proceed with surgery. In somepatients the risk of intervention or correctivecardiac surgery may approach or evenexceed the risk of the proposed noncardiac

surgery. This approach may be appropriate,however, if it also significantly improvesthe patients long-term prognosis.

For some patients, a careful considerationof clinical, surgery-specific, and functionalstatus attributes leads to a decision toproceed to coronary angiography.

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such as presence of both ECG ischemia andthallium redistribution after pharmacologicalstress or multisegment redistribution, where-

as long-term risk of death or MI may bebetter predicted by the presence of reversibleand/or fixed thallium (or comparable radio-pharmaceutical) defects.

Pharmacological stress testing involvingechocardiography has also emerged as apromising method for stratifying coronaryrisk before noncardiac surgery. While theaccumulated experience is less than thatassociated with myocardial perfusion imag-ing, dobutamine echocardiography appearsto provide similar information and safety.The opportunity to assess LV and valvulardysfunction simultaneously offers advantagesin some patients. As with all stress testing,proper identification of patients at mediumand high risk and quantification of the

degree of test abnormality may enhance pre-dictive accuracy.

Although both exercise and pharmacologicalstress testing provide useful informationfor risk prediction, no prospective study hasfirmly established the cost-effectiveness orefficacy of either for improving perioperative

in association with degree of functionalincapacity, symptoms of ischemia, severityof ischemia (eg, depth, time of onset, and

duration of ST-segment depression), andevidence of hemodynamic or electrical insta-bility during or after stress. This gradientalso correlates with increasing likelihood ofsevere and multivessel coronary disease.

Pharmacological Stress Testing

or patients who are unable to exercise,selected use of pharmacological stress

testing allows identification of patients withheightened risk of coronary events afternoncardiac surgery. Dipyridamole or adeno-sine with thallium (or comparable radiophar-maceutical) myocardial perfusion imagingappears to have a high sensitivity and speci-ficity for perioperative coronary events whenused in patients with preexistent clinical pre-dictors of risk, particularly angina pectoris,diabetes mellitus, prior MI, and prior CHFin patients undergoing vascular surgery.Quantitation of the degree of test abnormali-ty may allow a means of establishing a gradi-ent of risk much as is seen with exercisetesting. Perioperative ischemic events appearto correlate with the magnitude of ischemia

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Coronary Angiography

s indicated previously, it may be appro-priate to proceed directly to coronary

angiography in certain patients at high risk(Figure, page 32). Indications for coronaryangiography in the preoperative setting gen-erally are similar to those in the nonopera-tive setting (Table 4). First, it is essential toensure that management with percutaneoustransluminal coronary angioplasty (PTCA) orcoronary artery bypass graft (CABG) surgeryis a viable option. Otherwise, coronary

angiography may add to cost and risk with-out measurably benefitting outcome.Second, angiography should be reserved forpatients at very high risk, including thosewith evidence of advanced ischemic risk orsymptoms, and particularly those suspectedof having left main or three-vessel CAD.

or long-term outcomes. Use of these teststo help identify patients with advanced leftmain or three-vessel coronary disease is

justified, based upon overall knowledge ofmanagement of CAD. However, there is littleor no current information to justify their usein broad populations at low risk.

Ambulatory

Electrocardiographic Monitoring

everal investigators have shown thatdetection of ischemia by preoperative

24- to 48-hour monitoring correlates withincreased risk of both early postoperativeand late ischemic cardiac events. However,higher-risk patients may have baseline ECGabnormalities that preclude analysis, andat present the technique does not allowfor further quantification aimed at detectingthose patients at greatest risk. Use of thistechnique should be limited to institutionsin which preoperative monitoring of silentischemia has been shown to be effective andin which a standardized monitoring protocolhas been devised.

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Management of Specific Preoperative

Cardiovascular Conditions

Hypertension

evere hypertension (eg, diastolic bloodpressure 110 mm Hg or greater) should

be controlled before surgery when possible.The decision to delay surgery because ofelevated blood pressure should take intoaccount the urgency of surgery and thepotential benefit of more intensive medicaltherapy. Continuation of preoperative anti-hypertensive treatment through the peri-operative period is critical, particularly foragents such as -blockers or clonidine, toavoid severe postoperative hypertension.

Valvular Heart Disease

ndications for evaluation and treatmentof valvular heart disease are identical to

those in the nonoperative setting. Sympto-matic stenotic lesions such as mitral andaortic stenosis are associated with risk ofperioperative severe CHF or shock and often

Implications of Risk Assessment

Strategies on Costs

he degree of variation in preoperativetesting before noncardiac surgery is sub-stantial, likely reflecting uncertainty aboutthe most efficacious strategy or strategies andthe lack of randomized clinical trials evalu-ating the impact of therapies on outcomes.Not surprisingly, formal cost-effectivenessanalyses of various methods of preoperativetesting and treatments have also yielded

highly varied results. In many of these analy-ses, only short-term effects were evaluated;long-term benefits were ignored. Given thisuncertainty, it is important for the clinicianto consider the cost implications of screen-ing strategies and, when possible, to relyon generally accepted strategies for treatingnonsurgical patients.

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Myocardial Heart Disease

ilated and hypertrophic cardiomyopathyare associated with an increased inci-

dence of perioperative CHF. Management isdirected toward maximizing preoperativehemodynamic status and providing intensivepostoperative medical therapy and surveil-lance. An estimate of hemodynamic reserveis useful for anticipating potential compli-cations arising from intraoperative and/orpostoperative stress.

Arrhythmias and Conduction Abnormalities

he presence of an arrhythmia or cardiacconduction disturbance should provoke

a careful evaluation for underlying cardio-pulmonary disease, drug toxicity, or meta-bolic abnormality. Therapy should be initiat-ed for symptomatic or hemodynamicallysignificant arrhythmias, first to reverse any

underlying cause and second to treat thearrhythmia. Indications for antiarrhythmictherapy and cardiac pacing are identical tothose in the nonoperative setting.

require percutaneous valvotomy or valvereplacement before noncardiac surgery tolower cardiac risk. Conversely, symptomatic

regurgitant valve disease (eg, aortic regurgita-tion and/or mitral regurgitation) is usuallybetter tolerated perioperatively and maybe stabilized before surgery with intensivemedical therapy and monitoring. It is thentreated definitively with valve repair orreplacement after noncardiac surgery. Thisis appropriate when a wait of several weeksor months before noncardiac surgery may

have severe consequences, for example, inpatients with surgically curable malignantneoplasms. Exceptions may include patientswith both severe valvular regurgitationand reduced LV function in whom overallhemodynamic reserve is so limited thatdestabilization during perioperative stressesis very likely.

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encountered in daily life, it may be reason-able to consider CABG before noncardiacsurgery. A number of observational studies

have shown that patients with coronaryheart disease who have successfully under-gone CABG are at lower cardiac risk whenthey undergo noncardiac surgery.

Coronary Artery Angioplasty

s with CABG, there are no controlledtrials comparing perioperative cardiac

outcome after noncardiac surgery for

patients treated with preoperative PTCAversus medical therapy. The results ofseveral small observational series suggestthat cardiac death is infrequent in patientswho have coronary angioplasty before non-cardiac surgery. Several studies have demon-strated a number of complications fromangioplasty, including emergency CABG insome patients. Until further data are avail-able, the indications for PTCA in the peri-operative setting are similar to those in theACC/AHA guidelines for use of PTCA ingeneral.*


Preoperative Coronary

Revascularization

Coronary Artery Bypass Graft Surgery

he indications for CABG before non-cardiac surgery are identical to those

reviewed in the ACC/AHA guidelines forCABG.* Because the cardiac risk of coronarybypass surgery itself often exceeds that ofnoncardiac surgery, CABG is rarely indicatedto simply get a patient through the peri-operative moment. However, for the patient

with unstable coronary syndrome or theapparently stable patient who has advancedleft main or three-vessel disease, CABG maylead to improved long-term survival. Thislong-term benefit may also be true forsymptomatic patients with two-vessel dis-ease with high-grade proximal left anteriordescending (LAD) coronary artery stenosis

and diminished LV dysfunction. In suchcircumstances, when the stress of electivenoncardiac surgery is likely to exceed that


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Anesthetic Considerations and

Intraoperative Management

Anesthetic Agent

ll anesthetic techniques and drugs areassociated with known cardiac effects

that should be considered in the periopera-tive plan. There appears to be no one bestmyocardial protective anesthetic technique.Therefore, the choice of anesthetic and intra-operative monitors is best left to the discre-tion of the anesthesia care team. Opioid-

based anesthetics have become popularbecause of the cardiovascular stability asso-ciated with their use, but with high dosespostoperative ventilation is needed. All inhala-tional agents have cardiovascular effects,including myocardial depression, which maybe an important issue in patients with border-line LV reserve. Neuraxial techniques such asspinal and epidural anesthesia cause sympa-thetic blockade. Their use is frequently deter-mined by the dermatomal level of the surgicalprocedure. Infrainguinal procedures may beaccompanied by minimal hemodynamicchanges if neuraxial blockade is limited tothose dermatomes. Abdominal operations

Medical Therapy for

Coronary Artery Disease

here are very few randomized trials ofperioperative medical therapy to lowercardiac risk in patients having noncardiacsurgery, and the data are not sufficient todraw firm conclusions or recommendations.However, several points can be made on thebasis of limited observational data. First, ifpatients require -blockers, calcium channelblockers, and/or nitrates before surgery to

control or reduce angina or its ischemicequivalent, continuation of the preoperativemedical regimen into the operative and post-operative period may also protect againstischemic tendencies caused by the uniquestresses of the perioperative period. Thesame is true for therapies used to controlsymptoms of CHF. Second, observationalstudies suggest that -blockers reduce the

frequency of postoperative ischemia andin one study reduced the incidence ofperioperative MIs. Because postoperativeischemia is known to occur in a highpercentage of patients who subsequentlydevelop MI, protection against ischemiamay also reduce risk of MI.

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Intraoperative Nitroglycerin

here are insufficient data to determinewhether prophylactic intraoperative intra-

venous nitroglycerin is helpful or harmful inpatients at high risk. Because the vasodilat-ing properties of nitroglycerin are mimickedby several anesthetic agents, a combinationof agents may lead to significant hypotensionand even myocardial ischemia. When nitro-glycerin is used, the hemodynamic effects ofother agents used should be considered.

Transesophageal Echocardiography (TEE)

here are few data on the value of TEE-detected transient wall motion abnor-

malities (presumed myocardial ischemia)to predict cardiac morbidity in noncardiacsurgical patients. The largest experience todate suggests that the incremental valueof this technique for risk prediction is small.

Guidelines for the appropriate use of TEEto diagnose or guide therapy are being devel-oped by the American Society of Anesthesi-ologists and the Society of CardiovascularAnesthesiologists.*

*Anesthesiology 1996;84:986-1006.

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requiring a high dermatomal level of anesthe-sia may result in more profound effects,including hypotension and reflex tachycardiaif preload falls or hypotension without tachy-cardia if cardioaccelerators are inhibited byhigh-level blockade. Advocates of monitoredanesthesia care, in which local anesthesia issupplemented by intravenous sedation/anal-gesia, have argued that this technique caneliminate the undesirable effects of general orneuraxial techniques, but no studies haveestablished this. Furthermore, failure to pro-

duce complete local anesthesia/analgesia canlead to increased stress response, which mayproduce myocardial ischemia or depression.

Perioperative Pain Management

atient-controlled intravenous and/orepidural analgesia has become a popular

method for reducing severity and duration ofpostoperative pain. Several studies suggestthat effective pain management leads to areduction in postoperative catecholaminesurges and hypercoagulability, both of whichcan theoretically impact myocardial ischemia.

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Intraoperative and Postoperative

ST-Segment Monitoring

ntraoperative and postoperative ST

changes indicating myocardial ischemiahave been found to be strong predictors ofperioperative MI in patients at high clinicalrisk who undergo noncardiac surgery.Similarly, postoperative ischemia is a signifi-cant predictor of long-term MI and cardiacdeath. Conversely, ST depression may occurin patients at low risk who undergo non-cardiac surgery. Often this is not associated

with regional wall motion abnormalities,which raises the question whether this isischemia or a nonspecific finding. Presentlythere are few data on the cost-effectivenessof ST-segment monitoring for the purposesof reducing perioperative morbidity in anypatient population. Accumulating evidencesuggests that proper use of computerized ST-segment analysis in appropriately selected

patients at high risk may improve sensitivityfor detection of myocardial ischemia, whichcould lead to improved perioperative andlong-term risk assessment and treatment.

Perioperative Surveillance

Pulmonary Artery Catheters

lthough a great deal of literature hasevaluated the usefulness of pulmonary

artery catheters in treating perioperativepatients, very few studies have comparedoutcomes in patients treated with or withoutsuch monitoring. The American Society ofAnesthesiologists recommends that thefollowing three variables are particularlyimportant in assessing benefit versus risk of

pulmonary artery catheter use: diseaseseverity, magnitude of anticipated surgicalprocedure, and practice setting. The extentof expected fluid shifts is a primary concernwith regard to surgery. Current evidenceindicates that patients most likely to benefitfrom use of pulmonary artery catheters inthe perioperative period are those with arecent MI complicated by CHF, those with

significant CAD who are undergoing proce-dures associated with significant hemo-dynamic stress, and those with systolic ordiastolic LV dysfunction, cardiomyopathy,and valvular disease undergoing high-riskoperations.

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Surveillance for Perioperative

Myocardial Infarction

ery few studies have examined the

optimal method for diagnosing periopera-tive MI. Clinical symptoms, postoperativeECG changes, and elevation of the MBfraction of creatine kinase (CK) have beenmost extensively studied. Newer myocar-dial-specific enzyme elevations such astroponin-I, troponin-T, or CK-MB isoformsmay also have value. No single strategy orcombination of strategies can be strongly

advocated, given the paucity of current com-parative evidence. In patients withoutknown CAD, surveillance should probablybe restricted to patients showing signs ofcardiovascular dysfunction. In patients withknown or suspected CAD undergoing high-risk procedures, obtaining electrocardio-grams at baseline, immediately after theprocedure, and for the first 2 postoperative

days appears to be cost-effective. Use ofcardiac enzymes is best reserved for patientswith clinical, electrocardiographic, orhemodynamic evidence of cardiovasculardysfunction.

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Postoperative Therapy and

Long-Term Management

hen possible, postoperative manage-ment should include assessment andmanagement of modifiable risk factors forCAD, heart failure, hypertension, stroke, andother cardiovascular diseases. For manypatients, the need for noncardiac surgerymay be their first opportunity for a systematiccardiovascular evaluation. Assessment forhypercholesterolemia, smoking, hyperten-

sion, diabetes, physical inactivity, peripheralvascular disease, cardiac murmur(s),arrhythmias, conduction abnormalities, peri-operative ischemia, and postoperative MImay lead to evaluation and treatments thatreduce future cardiovascular risk. In particu-lar, patients who experience repetitive post-operative myocardial ischemia and/or sustaina perioperative MI are at substantially elevat-

ed risk for MI or cardiac death during long-term follow-up. These patients should be aparticular focus for risk factor interventionsand future risk stratification and therapy.

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Need fornoncardiac

surgery

Urgent orelectivesurgery

Postoperative riskstratification and risk

factor management

Coronaryrevascularizationwithin 5 years?

YesRecurrentsymptomsor signs?

Recent

coronaryevaluation

No

Recent coronary

angiogram orstress test?

Favorable resultand no changein symptomsYes

No

Clinicalpredictors

Major clinicalpredictors

Intermediateclinical

predictor

Minor or noclinical

predictors**

Go toConsider delay

or cancelnoncardiac surgery

Emergency

surgery

No

Yes

Unfavorableresult or changein symptoms

Operatingroom

Operatingroom

Considercoronary

angiography

Go to

Medicalmanagement and

risk factormodification

Subsequent caredictated byfindings and

treatment results

ACC/ AHA Guidelines for Perioperative Cardiovascular Evaluation for Noncardiac Surgery*

Step 1

Step 2

Step 3

Step 4

Step 5

Major Clinical

Predictors

s Unstable coronarysyndromes

s Decompensated CHF

s Significant arrhythmias(see table 1)

s Severe valvular disease

Step 6 Step 7

Stepwise Approach to

Preoperative Cardiac AssessmentSteps are discussed in text.

Clinical predictors

Functional capacity

Surgical risk

Noninvasive testing

Invasive testing

Poor(4 METs)

Intermediateor low surgicalrisk procedure

Low surgicalrisk procedure

Noninvasivetesting

Operatingroom

Postoperativerisk stratificationand risk factor

reduction

Considercoronary

angiography

Subsequentcare* dictated

by findings andtreatment results

Low risk

Step 6

Step 8

Intermediate

Clinical Predictors

s Mild angina pectoris

s Prior MI

s Compensated or prior CHF

s Diabetes mellitus

Highrisk

Continued on page 34.


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Table 2

Estimated Energy Requirements

for Various Activities*

1 MET Can you take care of

yourself?

Eat, dress, or use the

toilet?

Walk indoors around the

house?

Walk a block or two on

level ground at 2-3 mph

or 3.2-4.8 km/h?

4 METs Do light work around

the house like dusting

or washing dishes?

MET indicates metabolic equivalent.

* Adapted from the Duke Activity Status Index (Hlatky MA, Boineau RE, Higginbotham MB, Lee KL, Mark DB, Califf

RM, Cobb FR, Pryor DB. A brief self-administered questionnaire to determine functional capacity [the Duke Activity

Status Index]. Am J Cardiol 1989;64:651-654.) and AHA Exercise Standards (Fletcher GF, Balady G, Froelicher VF,

Hartley LH, Haskell WL, Pollock ML. Exercise standards: a statement for healthcare professionals from the American

Heart Association. Circulation 1995;91:580-615.).

Table 3

Cardiac Event Risk* Stratification for

Noncardiac Surgical Procedures

High

(Reported cardiac risk often >5%)

q Emergent major operations, particularly

in the elderly

q Aortic and other major vascular

q Peripheral vascular

q Anticipated prolonged surgical

procedures associated with large fluid

shifts and/or blood loss

* Combined incidence of cardiac death and nonfatal myocardial infarction.

Further preoperative cardiac testing is not generally required.

4 METs Climb a flight of stairs or walk

up a hill?

Walk on level ground at 4 mph or

6.4 km/h?

Run a short distance?

Do heavy work around the house

like scrubbing floors or lifting or

moving heavy furniture?

Participate in moderate recreational

activities like golf, bowling, dancing,

doubles tennis, or throwing a

baseball or football?>10 METs Participate in strenuous sports like

swimming, singles tennis, football,

basketball, or skiing?

w

w

Intermediate

(Reported cardiac risk generally


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Table 4

Indications for Coronary

Angiography* in Perioperative Evaluation

Before (or After) Noncardiac Surgery

Class I : Patients withsuspected or proven CAD:

q High-risk results during noninvasive testing

q Angina pectoris unresponsive to adequate

medical therapy

q Most patients with unstable angina pectoris

q Nondiagnostic or equivocal noninvasive

test in a high-risk patient (Table 1) undergoing

a high-risk noncardiac surgical procedure

(Table 3)

Class II :

q Intermediate-risk results during

noninvasive testing

q Nondiagnostic or equivocal noninvasive

test in a lower-risk patient (Table 1)

undergoing a high-risk noncardiac surgical

procedure (Table 3)

q Urgent noncardiac surgery in a patient

convalescing from acute MI

q Perioperative MI

* If results will affect management.

Class I: Conditions for which there is evidence for and/or general agreement that a procedure be performed or a

treatment is of benefit. Class II: Conditions for which there is a divergence of evidence and/or opinion about the treat-

ment. Class III: Conditions for which there is evidence and/or general agreement that the procedure is not necessary.

(CAD indicates coronary artery disease; MI, myocardial infarction; MET, metabolic equivalent; LV, left ventricular.)

Adapted from ACC/AHA Guidelines for Coronary Angiography. (JACC 1987:10:935-950; Circulation 1987;

76:963A-977A).

Class III:

q Low-risk noncardiac surgery (Table 3) in a

patient with known CAD and low-risk results

on noninvasive testing

q Screening for CAD without appropriate

noninvasive testing.

q Asymptomatic after coronary revascular-

ization, with excellent exercise capacity ( 7

METs)

q Mild stable angina in patients with good LV

function, low-risk noninvasive test resultsq Patient is not a candidate for coronary

revascularization because of concomitant

medical illness

q Prior technically adequate normal coronary

angiogram within previous 5 years

q Severe LV dysfunction (eg, ejection fraction

Non Cardiac Op

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