Resident Version
Preoperative Evaluation Module
Cardiac
created by Dr. Meg Lieberman
Updated Deepti Rao11/1/11
Objectives:
1. Be able to identify patients at significant risk for perioperative cardiac
morbidity.
2. Identify strategies to moderate that risk.
References:
1. Fleisher LA, Beckman JA, Brown KA, et al., ACC/AHA 2007 guideline on
perioperative cardiovascular evaluation and care for noncardiac surgery: A report of
the American College of Cardiology/American Heart Association Task Force on
Practice Guidelines (Committee to revise the 2002 Guidelines on Perioperative
Cardiovascular Evaluation for Noncardiac Surgery) J Am Coll Cardiol
2007;50:e159-242.
2. Lee TH, Marcantonio ER, Mangione CM, et al, Derivation and Prospective
Validation of a Simple Index for Prediction of Cardiac Risk of Major Noncardiac
Surgery. Circulation 1999; 100: 1043-9.
3. Devereaux PJ; Goldman L; Cook DJ; et al, Perioperative cardiac events in
patients undergoing noncardiac surgery: a review of the magnitude of the problem, the
pathophysiology of the events and methods to estimate and communicate risk. CMAJ
2005 Sep 13;173(6):627-34.
4. Effects of extended-release metoprolol succinate in patients undergoing noncardiac surgery (POISE trial): a randomised controlled trial. Lancet. 2008 May
31;371(9627):1839-47.
5. Lindenauer PK, Pekow P, Wang K, Perioperative Beta Blocker Therapy and
Mortality After Major Surgery. NEJM 2005; 353: 349-61.
Goals of Preoperative Medical Consultation:
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1. To assess the patient for known and unknown problems which are likely to affect
surgical morbidity.
2. To determine, in the setting of those problems and the proposed procedure, the
risk to the patient
3. To intervene to minimize those risks (and optimize the patient) or to delay or
change the proposed procedure
4. To recognize potential complications of the procedure and recommend
prophylaxis for those complications or help to treat those complications
CARDIAC EVALUATION:
Cardiovascular risks are some of the highest risks patients undergo when having major
surgery, not only due to surgical factors like volume shifts, blood loss and increased
myocardial oxygen demands but also due to patient factors both known and unknown.
One of the more commonly used algorithms for assessing cardiac risk is the 2007
ACC/AHA guideline (1). It is evidence based and a collaboration of multiple societies
including not only cardiologists but also anesthesiologists. (See back for a table outlining
the schema for the classification of recommendations level of evidence)
Cardiac evaluation and care algorithm for noncardiac surgery based on active clinical conditions, known
cardiovascular disease, or cardiac risk factors for patients 50 years of age or greater
ACC/AHA: American College of Cardiology/American Heart Association; HR: heart rate; LOE:
level of evidence; MET: metabolic equivalent..
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Clinical risk factors include ischemic heart disease, compensated or prior heart failure,
diabetes mellitus, renal insufficiency, and cerebrovascular disease.
Consider perioperative beta blockade (see Table 5) for populations in which this has been
shown to reduce cardiac morbidity/mortality.
Step 1: Need for emergency noncardiac surgery?
This is relatively straight forward. If a patient has a condition requiring emergency surgery,
for example s/p mva with a ruptured spleen, then preoperative evaluation of cardiac risk is
unnecessary. These patients, if there is some concern about cardiac issues, should be
assessed post op.
Step 2: Active cardiac conditions
Major predictors that require intensive management and may lead to delay in or cancellation
of the operative procedure




Unstable coronary syndromes including unstable or severe angina or recent MI
Decompensated heart failure including NYHA functional class IV or worsening or newonset HF
Significant arrhythmias including high grade AV block, symptomatic ventricular
arrhythmias, supraventricular arrhythmias with ventricular rate > 100 bpm at rest,
symptomatic bradycardia, and newly recognized ventricular tachycardia
Severe heart valve disease including severe aortic stenosis or symptomatic mitral
stenosis
These “active cardiac conditions” should cause at least a close evaluation if not further
intervention and/or reconsideration of a surgery.
Step 3: Low risk surgery?
ACC/AHA guideline summary: Cardiac risk stratification for noncardiac surgical procedures
High risk (reported risk of cardiac death or nonfatal myocardial infarction [MI] often)
 Aortic and other major vascular surgery
 Peripheral arterial surgery
Intermediate risk (reported risk of cardiac death or nonfatal MI generally 1 to 5 percent)
 Carotid endarterectomy
 Head and neck surgery
 Intraperitoneal and intrathoracic surgery
 Orthopedic surgery
 Prostate surgery
Low risk* (reported risk of cardiac death or nonfatal MI generally less than 1 percent)
 Ambulatory surgery
 Endoscopic procedures
 Superficial procedure
 Cataract surgery
 Breast surgery
* Do not generally require further preoperative cardiac testing.
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It is relatively easy to remember these classes if you remember that the high risk surgeries
are basically all the vascular surgeries except carotid endarterectomy and the low risk
surgeries are basically all the outpatient/ambulatory procedures.
Step 4: Good functional capacity (MET level greater than or equal to 4) without
symptoms?
1 MET is defined as 3.5 mL O2 uptake/kg per min, which is the resting oxygen uptake in a
sitting position. Perioperative cardiac and long-term risk is increased in patients unable to
meet a 4-MET demand during most normal daily activities.
Some questions which may help get at this:

What is your normal daily routine?

Do you do your own housework including vacuuming, carrying laundry, moving
furniture? (4 or > METS)

Do you have stairs at home? Can you walk up a flight of stairs without chest pain or
significant shortness of breath? (4 METS)

How far can you walk on a level without getting short of breath or having to rest?

Do you exercise? If so what type, how often, how far and how fast?
Step 5: NO or unknown functional capacity
Goldman in the mid 70’s developed a cardiac risk index for noncardiac surgery based on 9
variables. Subsequently in the late 90’s this was revised into the Revised Goldman Cardiac
Risk Index (2). Based on studying over 3800 patients and by validation in another 1400+
patients 6 predictors were found to increase cardiac risk. Of these 5 are now used in the
ACC/AHA algorithm as “clinical risk factors.” (The other one was high risk surgery which is
addressed earlier in the algorithm)
1. History of ischemic heart disease: MI, +Stress Test, Current “typical” chest pain,
Nitrate use, Q waves on EKG; do not count prior
Coronary revasc proc unless one of the other criteria
met
2. History of congestive heart failure: Pulmonary edema, PND, Bilateral rales, S3,
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Pulmonary vascular redistribution on CXR.
3. History of cerebrovascular disease: TIA or stroke
4. Diabetes mellitus with preoperative treatment with insulin
5. Preoperative creatinine > 2.0 mg/dL
Risk of Major Cardiac Event (Cardiac death, MI, and nonfatal cardiac
arrest ):
Risk Factors
Risk
0
0.4%
1
0.9%
2
2.4%
3+
5.4%
(3)
CASE
You are called by the Neurosurgery Service to perform a preoperative evaluation of a 74
year old diabetic Navajo man with rheumatoid arthritis who sustained an atlantoaxial
dislocation. The patient speaks little English, but the family informs you that he was in
his usual state of health until he looked upwards several days ago and suddenly felt like
his head was falling off.
At baseline, his activity is limited to ambulating slowly indoors, holding on to furniture.
The family does not think he has experienced any chest discomfort, SOB, edema,
orthopnea or PND. He sleeps on two pillows at night. He has not reported any fever,
chills, or digestive disturbances, and they have not heard any cough.
PMH: RA
DM-II
Htn
Mild Asthma
Remote CVA
MEDS: Glyburide 10 mg. daily
Enalapril 10 mg. daily
Methotrexate 10 mg. weekly
Flomax 0.4 mg. daily
NKDA
P/S: Resides with son
Denies EtOH,tob
EXAM: Thin elderly male. T 98.8 HR 96 R 18 BP 163/92
HEENT: Symmetric, anicteric, mucous membranes moist NECK: Unable to examine
due to bulky brace extending to torso THORAX: Also limited, but CTA CV: RRR
S1S2 w/o m/g/r
ABD: Scaphoid, NT, NABS< w/o HSM EXT: Bony deformities c/w longstanding
RA, no C/C/E NEURO: Alert, moving all extremities, nonfocal.
LAB: Hgb.-11.6 WBC-6.7 Plt.-167 Na–129 K–4.8 Cl–99 HCO3 -20 BUN -40 Cr2.4
Gluc. - 160
EKG: SR, 98, no diagnostic abnormality
PCXR: Poor quality due to overlying hardware and hypoinflation, but no gross
abnormalities
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QUESTIONS
1. According to the ACC/AHA guidelines what are the first two questions you should ask
yourself in assessing the patient’s preoperative cardiac risk?
#- Does this patient need emergency noncardiac surgery?
$- Does this patient have any active cardiac conditions?
&- How many clinical risk factors does this patient have?
a. # and $
b. # and &
c. $ and &
2. What is the patient’s procedure specific risk?
a. Low
b. Intermediate
c. High
3. The patient’s reported functional capacity corresponds with which class?
a. 1-3 METS
b. 4 METS
c. 5-10 METS
5.
How many clinical risk factors does the patient have and what are they?
6.
What will be your recommendation to the neurosurgeons regarding the patient
and his cardiac risk?
a. Proceed to surgery with no further interventions
b. Proceed to surgery but first start patient on propranolol at 10mg po tid
c. Proceed to surgery but first start patient on atenolol at 25mg daily, do not
titirate
d. Cancel surgery because patient’s risk is too high
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Perioperative Beta Blockers:
Not for everyone! Risks outweigh benefits in low risk individuals.
POISE trial (4) randomized >8K patients undergoing noncardiac surgery to 100mg
metoprolol before and after surgery, then 200mg daily after (high dose). Results showed
improved cardiac outcomes but nullification of benefits due to increased mortality mainly
due to increased stroke/hypotension.
Study by Lindauer et al. Retrospective study of >600K patients. Showed that patients
who had a clinically significant decrease in mortality from perioperative beta blockers
were those with a RCRI score of ≥3. Those who had a score of 2 had a small benefit.
(Remember RCRI score are the clinical risk factors above.)
Should be used: : In current beta blocker users, or independent indications for their use
Beta blockers titrated to heart rate and blood pressure are probably
recommended for patients undergoing vascular surgery who are at high cardiac risk owing to
coronary artery disease or the finding of cardiac ischemia on preoperative
testing (4,5). (Level of Evidence: B)
2. Beta blockers titrated to heart rate and blood pressure 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.*
(Level of Evidence: B)
3. Beta blockers titrated to heart rate and blood pressure are probably
recommended for patients in whom preoperative assessment identifies coronary heart
disease or high cardiac risk, as defined by the presence of more than 1 clinical risk
factor,* who are undergoing intermediate-risk or vascular surgery. (Level of Evidence: B)
(AHA focused update perioperative beta blockers)
Beta 1 selective preferred—Atenolol, metoprolol, bisoprolol
Benefits closely linked to heart rate control. Titrate to goal HR = 60, avoid hypotension.
(Circulation114:I344-9)
Ideally start >3 days preoperatively (weeks if possible). If necessary, can use Atenolol 5
mg IV/5min. in pre-op area; repeat after 10 min if tolerated to goal HR = 60.
Continue for at least one month postop
7.
One of the neurosurgery interns asks about need for stress testing in this patient.
What do you tell him?
Answer: In most patients without active angina/mi and with intermediate risk semiurgent surgery further cardiac testing almost never will change management.
Of note:
Stress Imaging:
Valuable in the management of high-risk outpatients (patients with 3 or more RCRI
criteria or 1-2 RCRI criteria and poor functional status, hx CAD, or undergoing high risk
surgery) since negative predictive value is excellent, but positive predictive value is poor.
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Thus, most useful in reassuring us when a patient thought to be at high risk is found to
have a negative study.
Cardiac Catheterization/Revascularization:
Beneficial preoperatively only if otherwise indicated (in non-operative setting) – CARP
trial (NEJM 351:2795-2804).
Also careful selection of patients imperative as stopping anti-platelet agents for surgery
may actually increase cardiac risk. (Drug eluting stent—cannot stop antiplatelet for 1
year, metal stent cannot stop for 4-6 weeks)
And finally
What else is useful in reducing perioperative cardiac risk?
Perioperative normothermia: Cardiac event rate 1.4% (vs. 6.3%) in patients kept warm
in OR. (JAMA 277: 1127-34).
Clonidine: May be helpful in patients undergoing vasc surg but not enough evidence in
patients undergoing noncardiac surgery (Wijeysundera, Am J Med, 2003)
Statins: ACC/AHA guidelines…for patients currently taking statin and scheduled for
surgery, statins should be continued (level of evid B), statins should be considered in
those undergoing vasc surg (B, probably should already be on for other indications) and
for patients with 1 clinical risk factor and intermediate risk surgery, statins may be
considered (evid C)
There is evidence in patients undergoing vascular surgery that statin withdrawl increases
the frequency of cardiac events. (Schouten, Am J Cardiol 2007)
ASA : In a metanalysis, asa was shown to increase bleeding complications 1.5 fold but
increase the frequency of ACS by 10%.. May want to consider continuing the asa for
surgery only if bleeding may be associated with substantial death or disability (Burger, J
Int Med, 2005)
Valvuloplasty? Valve stenting? In a few selected candidates
Detection for periop MI: It’s unclear which patients should be surveilled but recent study
showed 11% 30 day mortality with poor monitoring and follow up. (Devereaux, Ann Int
Med, 2011)
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Post Module Evaluation
Please place completed evaluation in an interdepartmental mail envelope and address to
Dr. Wendy Gerstein, Department of Medicine, VAMC (111).
1) Topic of module:__________________________
2) On a scale of 1-5, how effective was this module for learning this topic? _________
(1= not effective at all, 5 = extremely effective)
3) Were there any obvious errors, confusing data, or omissions? Please list/comment
below:
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
4) Was the attending involved in the teaching of this module? Yes/no (please circle).
5) Please provide any further comments/feedback about this module, or the inpatient
curriculum in general:
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
6) Please circle one:
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Attending
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Intern
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