ACC/AHA 2007 Guidelines on Perioperative Cardiovascular Evaluation and Care for noncardiac surgery Dr. Sonia Anand McMaster University.

ACC/AHA 2007 Guidelines on Perioperative Cardiovascular

Evaluation and Care for noncardiac surgery

Dr. Sonia Anand

McMaster University

Overview

• Guidelines- reflect evidence synthesis and consensus

• Evidence as of October 2007

• Important Decision points:– Urgent vs Elective Surgery– High risk surgery vs intermediate vs low– Active Cardiac Condition vs non-active

The Search For High Risk

Methods for Assessing Risk Pre-Operatively

Patient Based– High risk conditions– Functional Capacity

Surgery Based– Vascular Surgery– Emergency surgery

Intervention Based–Medications–Revascularization

Six Independent predictors of cardiac risk

1) ischemic heart disease

2) congestive heart failure

3) cerebrovascular disease

4) high risk surgery (AAA, orthopedic sx)

5) pre-operative insulin tx for diabetes

6) preoperative creatinine for creat > 2 mg/dL

Lee et al

Active/Major Cardiac Conditions

• Unstable Coronary Conditions

• Decompensated CHF

• Significant arrhythmias (i.e. 3 HB, new ⁰Vtach)

• Severe Valvular Disease (aortic stenosis >40 mm hg gradient or valve area <1.0cm₂)???????

Non-Active Cardiac Factors

• Intermediate Risk • Hx of CHD• History of prior

CHF• Hx of stroke• Diabetes • Renal insufficiency

• Minor Risk*• Age > 70• Abnormal ECG• Nonsinus rhythm• Uncontrolled

systolic BP

* Not associated with cardiac risk

Functional Capacity

• Functional status has shown to be a reliable periop and long-term predictor of cardiac events

• Functional status determined based on ability to do ADL’s

• MET: metabolic equivalent resting oxygen consumption of 70 kg, 40 yr old man at rest

• Periop risk is increased if person cannot > 4 METS

1 MET 4 MET 10 MET

Eat, d

ress

DO li

ght h

ouse

wor

k i.e.

Was

hing d

ishes

Climb a

fligh

t of s

tairs

Run a sh

ort d

istan

ces

Mod

erat

e rec

reat

iona

l gol

f, da

ncin

g, b

aseb

all

Stre

nuou

s spo

rts s

wimm

ing,

bas

ketb

all

The Trump Card: Functional Capacity

• Perioperative cardiac risk is increased in patients unable to exercise 4 METs

• Functional capacity can be estimated in the office

– Energy expenditure for eating, dressing, walking around house, dishwashing ranges from 1-4 METs

– Climbing a flight of stairs, running a short distance, scrubbing floors, and golf ranges from 4-10 METs

– Swimming and singles tennis exceeds 10 METs

Surgery Risk Type

Type Cardiac risk examples

High > 5% Aortic, peripheral vasc sx

Intermediate risk 1-5% IntraperitonealIntrathoracicCarotid EndHead and neckOrthopedic SxProstate Sx

Low <1% Endoscopic proceduresSuperficialCataract SxBreast SxAmbulatory Sx

Surgery-Specific Risk: High Risk*

• Major emergency surgery

• Vascular surgery including: aortic surgery, infra-inguinal bypass

• Prolonged surgery with large fluid shifts or blood loss

* Reported risk of cardiac death or nonfatal MI >5%

Stepwise Approach

• Step 1: Determine urgency of surgery

• Step 2: Active cardiac condition?-→test

• Step 3: Undergoing low-risk surgery? < 1%*

• Step 4: Good functional capacity?

* Combined morbidity and mortality < 1% even in high risk

patients

The Catheterization Questions to Ask Yourself

• Does this patient have symptomatic coronary disease that will have a mortality benefit from revascularization now?

• Am I willing to send the patient to CABG?

• Am I doing this just to know the anatomy?

Is pre-op coronary revasc advantageous?

• If high risk surgery and patient has active cardiac issue

• Functional test and perfusion Imaging and if

• L main 50% or 3 VD, 2VD + LAD Prox, LVEF < 20%, aortic stenosis – consider revasc pre-op

• CARP – if none of these – no advantage of revasc

Functional Test

• Exercise test with ECG

• If abnormal ECG, Rx perfusion imaging– Adenosine– Dipyridamole– Dobutamine– Dobutamine stress echo

Effect of Prior CABG on Cardiac Risk of Vascular Surgery: The CASS Registry

0

2

4

6

8

10

No CAD CAD:Medical Rx

CAD: CABG

(n=314)

Periop MIDeath

3.0

0

8.5

2.8

0.6 1.1

***

***

*

*

Eagle et al. Circulation, 1997

Coronary Revascularization Does Not Improve Immediate or Long-Term Outcomes

0

5

10

15

20

25

Post-Op MI 30 DayMortality

2.7 YearMortality

Revascularization Conservative Mgmt

510 VA pts, aged 66 years, with stable CAD, scheduled for elective AAA repair (33%) or infrainguinal bypass (67%), randomized toRevasc (PCI 59%, CABG 41%) or conservative management.

McFalls, E. CARP Trial;AHA 2004

High Risk Patients & Revascularization Pre-Op

101 pts with extensive ischemia randomly assigned to pre-op revascularization or not. Endpoints: all-cause death or MI at 30 days and 1-year follow-up.

%

7 14 21 28

50

40

30

20

10

0

Days since surgery Months since surgery

0 3 6 9 12

Poldermans, D. JACC 2007; 49(17): 1763

2VD in 12 (24%), 3VD in 33 (67%), Left main in 4 (8%).

The Effect of Percutaneous Revascularization Above Optimal Medical Therapy:

COURAGE

1.0

0.9

0.8

0.7

0.6

0.5

0 1 2 3 4 5 6 7

Years

Su

rviv

al F

ree

of

De

ath

/MI

2287 Pts w/myocardial ischemia and CAD randomized to PCI with

optimal medical therapy (PCI group) and 1138 to medical therapy alone.

Boden, W. NEJM 2007; 356:1503

Medical therapy

PCI + Medical therapy

STENTS

If upcoming Sx is known then PTCA alone or BMS with 4-6 wks dual antiplatelet tx after

If received DES....– 1) postpone sx until > 12 months,– 2) do sx on both asa+clop – 3) do sx on single ap tx

Use of a DES for coronary revascularization before imminent or planned non cardiac sx that will necessitate d/c of antiplatelet agents is not recommended

Medical tx

1) beta blockers-if on keep them if not....

2) Statins continue, ? Start -need randomized trials

Statins Improve Survival After Vascular Surgery

Durazzo, AES. JVS 2004:39(5):975

100 pts randomized 20 mg atorvastatin or placebo for 45 days.Vascular surgery ~ 30 days after randomization. F/U 6 months

Primary EndpointCV death +NFMI+Ischemic stroke+Unstable Angina

Statins Improve Long-Term Survival After Vascular Surgery

0 20 40 60 80 100

1.00

.75

.50

.25

0

Time (months)

Su

rviv

al

Statin (+)

Statin (-)

Ward, RP. Int J Card 2005; 104(3):264

Retrospective review of 446 consecutive infrainguinal bypass surgeries

p < 0.004

Other Issues

• DVT/PE prophylaxis

• Anesthetic technique-volatile agent with general anesthetic - ↓ troponin ↑ LV function >> propofol, midazolam, balanced anesthesia (Grade B)

• No evidence that epidural anesthesia >>general anesthesia for cardiac outcomes

• Routine troponin monitoring not recommended

Surveillance for Perioperative Myocardial Infarction

• ECGs–All intermediate and high-risk patients

should get a post-op ECG.–As need for signs or symptoms of

ischemia

• Troponin / CK – In patients with signs or symptoms of

ischemia–Do not do screening biomarkers

High Risk Features

• Severe obstructive or restrictive pulmonary disease

• Diabetes

• Renal impairment

• Anemia, polycythemia, thrombocytosis

PCI pre-op

• ST-elevation MI

• Unstable angina

• Non ST elevation MI

2007 ACC/AHA Perioperative Guidelines

Take Home Messages• Unstable syndromes require management prior to surgery. Look

for

– Unstable angina

– Signs of heart failure

– Stenotic valve lesions

– Ventricular arrhythmias

• Functional tolerance is the best single predictor of outcome

• Be very specific in your history (one step at at time, regular or slow pace, etc)

• If patient on beta blockers & statins continue them, more trials to mandate them

• PCI/CABG only if patient needs it independent of surgery. Think twice because of stent data and delays.