Chapter 25: Cardiovascular Disease

Question 1

Incidence of myocardial reinfarction periop

Answer 1

2-6 months post-op: up to 37%.
>6 months post-op: 5-6%.
Most reinfarctions occur 48-72hrs post-op.
Highest risk in thoracic and upper abdominal procedures lasting >3 hours.

Question 2

Factors that don’t predispose to reinfarction

Answer 2

1) site of previous MI
2) history of prior CABG
3) type/site of surgery if short case (<3 hours)
4) type of anesthesia

Question 3

Preferred peri-operative beta-blocker for cardiac risk reduction

Answer 3

Atenolol or bisoprolol (B1 selective), but no evidence for switching b-blockers. Metoprolol shown less effective, but also B1 selective and can be used.

Question 4

Start b-blocker pre-op?

Answer 4

In non-cardiac surgery, evidence shows an association of beta-blockers with increased all-cause mortality and stroke rate (Cochrane 2018.

In cardiac surgery, they can substantially reduce the high burden of supraventricular and ventricular arrhythmias in the aftermath of surgery. Their influence on mortality, AMI, stroke, congestive heart failure, hypotension and bradycardia in this setting remains unclear.

Question 5

What was the POISE trial?

Answer 5

Perioperative Ischemic Evaluation (POISE), found that prophylactic b-blocker use initiated on the morning of a noncardiac surgical procedure was
associated with a higher risk for bradycardia, stroke, and mortality.

Question 6

Start clonidine pre-op?

Answer 6

POISE-2 trial: administration of low-dose clonidine in patients undergoing noncardiac surgery did not reduce the rate of the composite outcome of death or nonfatal myocardial infarction; it did, however, increase the risk of clinically important hypotension and nonfatal cardiac arrest.

Question 7

Start statin pre-op?

Answer 7

Perioperative statins appear to be protective against postoperative myocardial infarction in non-cardiac surgery and associated with higher AKI in cardiac surgery. Controversial and no strong evidence.
Level B evidence that starting statin in vascular surgery patients is reasonable.

Question 8

Artery and Myocardial region associated with II, III and aVF.

Answer 8

RCA; RA, SA node, AV node, RV

Question 9

Artery and Myocardial region associated with V3-V5

Answer 9

LAD; Anterolateral aspects of LV

Question 10

Artery and Myocardial region associated with I and aVL

Answer 10

LCX; Posterolateral aspects of LV

Question 11

RCRI criteria

Answer 11

Cr>2.0, CHF, IDDM, High risk surgery (intrathoracic, intraabdominal, or suprainguinal vascular), Prior CVA/TIA, CAD

0 or 1 = low risk, >=2 = elevated risk

Question 12

Who should get a pre-op 12 lead ECG?

Answer 12

Known coronary dz or other structural heart dz, except for low risk surgery.

May be considered in asymptomatic patients, except for low risk surgery.

Question 13

Who should get a pre-op LV function analysis (e.g. echo)?

Answer 13

Dyspnea of unknown origin, HF with worsening dyspnea or other clinical worsening.

May consider reassessment of known LV dysfunction if no assessment within a year.

Question 14

Do you need exercise stress testing for patients with elevated risk of MACE, but moderate to excellent functional capacity?

Answer 14

No, reasonable to forgo and proceed to surgery with METS >4 (definitely for >10)

Question 15

Do you need exercise stress testing for patients with elevated risk of MACE, but poor functional capacity?

Answer 15

Yes, if it will change management.

Question 16

What should you look for on myocardial perfusion imaging to predict MACE?

Answer 16

Reversible perfusion defects predict events. Fixed defects do not.

Question 17

When can a patient have elective noncardiac surgery following PCI with stent?

Answer 17

BMS - 30 days post-implant
DES - 6 months post-implant optimally
(Per 2016 ACC/AHA)

Question 18

Can you consider elective noncardiac surgery at 4 months post-DES?

Answer 18

Yes, you can consider at 3 months, and if possible continue ASA, and restart P2Y12 inhibitor as soon as possible post-op. (If the risk of further delay of surgery is greater than the expected risks of stent thrombosis.)
Per 2016 ACC/AHA

Question 19

Which volatile anesthetic is associated with coronary steal? which is associated with tachycardia and hypertension?

Answer 19

Isoflurane

Desflurane (sympathetic stimulation with rapid increases)

Question 20

NMBs that evoke histamine release and decrease SBP

Answer 20

mivacurium and atracurium

Question 21

Rapid increases in desflurane may cause:

Answer 21

tachycardia, HTN, pHTN and bronchospasm

Question 22

Avoid in mitral stenosis

Answer 22

Tachycardia, AF w/ RVR
Decreased SVR
Hypoxemia/Hypoventilation (increased PVR)

Question 23

Avoid in mitral regurg

Answer 23

Bradycardia (goal 80-100)
Increased afterload
Myocardial depression

Question 24

What waveform is seen in mitral regurg?

Answer 24

PA wedge waveform as a large v wave and a rapid y descent

Question 25

B1 selective B-blockers

Answer 25

Bisoprolol, Esmolol, Atenolol, Metoprolol

Question 26

Nonselective B-blockers

Answer 26

Timolol, Nadolol, Sotalol, Propranolol

Question 27

Aortic stenosis murmur

Answer 27

systolic murmur in right 2nd intercostal space (radiates to right carotid)

Question 28

Critical aortic stenosis pressure gradient and valve area

Question 29

Hemodynamically significant aortic stenosis pressure gradient and valve area

Answer 29

<1.2 cm2

Question 30

Avoid in aortic stenosis

Answer 30

Bradycardia
Atrial fibrillation
Hypotension (need to maintain afterload)

Question 31

Why have a defibrillator nearby for aortic stenosis?

Answer 31

Compressions are unlikely to generate adequate stroke volume across stenosed valve

Question 32

Should you continue a patient’s statin or b-blocker perioperatively?

Answer 32

yes and yes (level B evidence)

- ACC/AHA 2014