Dr Gary Liew, MBBS, PhD, FRACP

US Board Certified in Cardiovascular CT

Executive Committee, Cardiac Institute, Epworth Healthcare

Senior Fellow, University of Melbourne

Clinical Senior Lecturer, University of Adelaide

Dr Gary Liew, MBBS, PhD, FRACP

US Board Certified in Cardiovascular CT

Executive Committee, Cardiac Institute, Epworth Healthcare

Senior Fellow, University of Melbourne

Clinical Senior Lecturer, University of Adelaide

Cardiac Perioperative Risk Assessment

American Heart Association Guidelines

Cardiac Perioperative Risk Assessment

American Heart Association Guidelines

Perioperative

Cardiac Guidelines

American - AHA/ACC 2014

European - ESC / ESA 2014

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U.S. Perioperative GuidelinesFleisher et al, JACC 2014

European Perioperative GuidelinesKristensen et al, Eur Heart J, (2014) 35 , 2383–243

ESC Perioperative

Guidelines App

Topics

• Coronary Artery Disease

• Heart Failure

• Atrial Fibrillation & Arrhythmias

• Valvular Disease

• Pacemakers & ICDs

• Stepwise approach to Pre-Op testing

• Treatment options in Peri-Op period

Coronary Artery Disease

• Current ACS or unstable angina

• Timing surgery since previous AMI

< 1

Month

1 – 2

Months

2 – 3

Months

3 – 6

Months

AMI 32% 18% 8% 6%

Death 14% 11% 10% 9%

Heart Failure

• Patients with active / clinical heart failure

have higher post-op death (9%) than

patients with stable CAD (3%).

• Patients with LVEF < 30% highest risk

• 30-Day MACE rate based on symptoms:

Symptomatic

Heart Failure

Asymptomatic

LV systolic

Heart Failure

Asymptomatic

LV Diastolic

Heart Failure

MACE 49% 23% 18%

Valvular Heart Disease

Valve stenosis worse than

valve regurgitation

• Severe symptomatic AS or MS should be

fixed prior to elective surgery

• Severe asymptomatic AS may be go ahead

with caution and HDU monitoring

• Severe AS = AVA < 1.0cm2 or mean

gradient > 40 mmHg (normal LVEF)

• Severe asymptomatic AR or MR with

normal LVEF may go ahead with caution

and HDU monitoring

Atrial Fibrillation

• Rate control is key – continue pre-op

beta-blocker or digoxin. Diltiazem can be

useful in asthmatics.

• Consult with cardiologist about stopping

anti-coagulants. No bridging with

clexane / heparin unless previous stroke

or high CHADs-Vasc score or valvular.

• NOACs only stop 48 – 72 hours pre-op.

Other arrhythmias

• Isolated RBBB or LBBB are fine to

proceed (ie. No new CCF or CAD)

• 2nd degree 2:1 AV block or CHB may

require temporary pacing or pacemaker

• Beware Trifascicular Block =

• RBBB + 1st degree AV block + left or

right axis deviation (LAFB or LPFB)

• No pacing if asymptomatic but CHB.

Trifascicular Block

- one step away from CHB• RBBB + 1st degree AV block + left or

right axis deviation (LAFB or LPFB)

RBBB

1st Degree AV Block = PR > 1 Big Square

Left Axis Deviation

Cardiac Implantable Electronic Devices (CIEDs)

• INVOLVE CIED TECHNICIAN PRE / PERI-OP

• Electro-cautery can cause inhibition of pacing,

oversensing in ICDs = inappropriate shocks

• Magnet application and/or reprogramming can

avoid these problems

• Mono-polar cautery can reduce EMI

(electromagnetic interference)

Stepwise Approach

1. Urgent Surgery

2. ACS or unstable cardiac conditions

3. What is the risk of the procedure?

4. What is the functional capacity of patient?

Good (> 4 METS = proceed)

5. Poor functional capacity then consider risk

of surgery

6. Clinical risk factors for High Risk Surgery

7. Functional testing

Step 1: Urgent Surgery

• Emergency / Urgent Surgery will

proceed – no time to order investigations

• Patient or surgical factors will dictate

strategy

• Cardiac monitoring and surveillance for

complications eg. MI, arrhythmias

• Continuation of medical therapy for

chronic conditions eg. Aspirin, B-blocker

Step 2: Active / Unstable cardiac

• Unstable Angina

• Recent MI (< 60 days) or residual ischaemia

• Acute heart failure

• Significant cardiac arrhythmias

• Symptomatic valvular heart disease

• Delay procedure

• Consultation with relevant specialists

• Investigate and optimize treatment

Step 3: Risk of surgery30-Day risk of MI and death

No further testing needed;

proceed to surgery

Step 4: Functional Capacity

• Good > 4 METs & Asymptomatic

• Proceed to surgery

Step 5: Poor function < 4 METS

• If Moderate or High Risk Surgery then

consult and consider functional test

• Stress Echocardiogram

• Stress Nuclear Perfusion

Step 6: Clinical Risk Factors

Revised Cardiac Risk Index (RCRI)

• IHD – angina or previous AMI

• Heart Failure

• Stroke or TIA

• CKD – Cr > 170 or CrCl < 60

• Diabetes requiring insulin

• ≤ 2 factors = rest echo +/- stress

• ≥ 3 factors = Stress testing

Lee et al, Circulation 1999: 100, 1043-1049

RCRI Calculator App

Step 7: Functional testing

• Stress Echo (treadmill vs. dobutamine)

• LBBB, obesity, severe COAD

• Stress Nuclear Perfusion

• Treadmill / bike vs Persantin or

Adenosine, Dobutamine

• Cardiac MRI – access issue & cost

• Coronary CTA – not indicated for routine

pre-op testing.

• Routine coronary angiogram – not indicated

Routine ECG or Echo?

Medications Peri-Op

• Beta-blockers

• Statins

• ACEi / ARBs

Beta-blockers

Other therapies

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Stents and Dual-Antiplatelets

• Bare metal stents – min. 4 weeks

• DES – min. 12 months but ? 6 months

• If surgery urgent, keep Aspirin going.

• Risk of MI = <30 days 15%, <6 months 8%

Summary

• Consider surgical & patient risk

• Patient functional status

• Low risk procedures – no need to test

• Mod – High risk surgery = consider patient status / risk factors

• Continue aspirin, statins, ACEi, ß–blockers for chronic, stable patients.

• Not start new aspirin or ß–blockers routinely unless indicated

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