Week 13 Handout Flipped Classrooms: CAD

Question 1

What is Coronary Artery Disease (CAD)?

Answer 1

CAD is the atherosclerotic narrowing of coronary arteries leading to decreased oxygen supply.

Question 2

What causes ischemia and infarction in CAD?

Answer 2

A supply/demand mismatch during stress results in ischemia and can lead to infarction.

Question 3

What are the main coronary arteries?

Answer 3

The main coronary arteries include the left main artery (which branches into the LAD and circumflex) and the right coronary artery.

Question 4

What does the left main artery supply?

Answer 4

The LAD supplies the septum and anterior left ventricle (LV), while the circumflex supplies the lateral LV and part of the left atrium (LA).

Question 5

What does the right coronary artery supply?

Answer 5

The right coronary artery supplies the right atrium (RA), right ventricle (RV), inferior LV, and PDA (posterior LV/septum).

Question 6

When does coronary perfusion occur?

Answer 6

Coronary perfusion occurs during diastole.

Question 7

What is the formula for Coronary Perfusion Pressure (CPP)?

Answer 7

CPP = DBP − LVEDP.

Question 8

What are the risk factors for CAD?

Answer 8

Risk factors include hypertension (HTN), diabetes mellitus (DM), smoking, obesity, dyslipidemia, age >65, male sex, sedentary lifestyle, and family history.

Question 9

What is a classic sign of CAD?

Answer 9

Angina (stable, unstable, variant) is the classic sign of CAD.

Question 10

What is silent ischemia?

Answer 10

Silent ischemia is common in the elderly and diabetics, characterized by no chest pain and often a Q Wave on ECG.

Question 11

What are the symptoms of a myocardial infarction (MI)?

Answer 11

Symptoms include chest pain, diaphoresis, hypotension, dyspnea, and nausea.

Question 12

What are the signs of heart failure?

Answer 12

Signs of heart failure include orthopnea, pulmonary congestion, and peripheral edema.

Question 13

What is cardiogenic shock?

Answer 13

Cardiogenic shock presents with hypotension, altered mentation, oliguria, and cold extremities.

Question 14

What are common arrhythmias associated with CAD?

Answer 14

Common arrhythmias include atrial fibrillation (AF), ventricular tachycardia (VT/VF), and bradyarrhythmias.

Question 15

What is the risk of sudden cardiac death in CAD?

Answer 15

Sudden cardiac death can occur in patients with CAD.

Question 16

What is the management indication for revascularization?

Answer 16

Indications include left main disease, triple-vessel disease with decreased LV function, and unstable angina.

FOOTNOTE**
Avoid routine revascularization in stable CAD patients

Question 17

What are the indications for CABG?

Answer 17

CABG indications include multivessel disease with proximal LAD involvement, failed PCI, two-vessel disease with proximal LAD, and severe ischemia without LAD.

Question 18

When should elective surgery be delayed post-MI?

Answer 18

Elective surgery should be delayed ≥60 days post-MI unless absolutely necessary.

FOOTNOTE**
Post-MI reinfarction mortality can reach 50%

Question 19

What are the Perioperative Reinfarction Rates?

Answer 19

• <30 days post-MI → 33% reinfarction risk
• 1–2 months post-MI → 19%
• 3–6 months post-MI → 6%
• > 6 months → Lowest risk

Question 20

What are the poor LV function indicators?

Answer 20

Indicators include EF <40%, LVEDP >18 mmHg, and CI <2.2 L/min/m².

Question 21

What are the intraoperative anesthesia goals?

Answer 21

Goals include maintaining myocardial oxygen supply-demand balance and avoiding increased heart rate and decreased blood pressure.

Question 22

What should be avoided in intraoperative management?

Answer 22

Avoid increased heart rate, decreased blood pressure, stress, hypothermia, tachycardia, and hypotension.

Question 23

What are preferred agents for anesthesia in CAD patients?

Answer 23

Preferred agents include phenylephrine, norepinephrine, esmolol, metoprolol, fentanyl, sufentanil, remifentanil, and sevoflurane.

Question 24

What should be monitored postoperatively in high-risk patients?

Answer 24

Monitor for low cardiac output, arrhythmias, ischemia, stroke, and graft complications.

Question 25

What should be maintained postoperatively?

Answer 25

Maintain normothermia, O₂ saturation >95%, and tight blood pressure and glucose control.

Question 26

What is the recommendation for clopidogrel postoperatively?

Answer 26

Resume clopidogrel as soon as bleeding permits.

Question 27

Surgical timing after MI with no stent?

Answer 27

Delay ≥ 2 weeks

Question 28

Surgical timing after MI with BMS?

Answer 28

Delay ≥ 30 days

Question 29

Surgical timing after MI with DES?

Answer 29

Delay ≥ 6 months

Question 30

DAPT management preoperatively?

Answer 30

Continue aspirin; Hold clopidogrel (Plavix) per cardiology guidance

Question 31

When to restart clopidogrel post-op?

Answer 31

Restart ASAP once bleeding risk is acceptable

Question 32

High-risk identifiers for CABG patients?

Answer 32

EF <40%, NYHA Class IV, Cardiogenic shock, May require IABP

Question 33

Management in recent PCI/ACS + emergent CABG?

Answer 33

Continue aspirin; Consider continuing GP IIb/IIIa inhibitors despite bleeding risks

Question 34

What should be done collaboratively in CABG?

Answer 34

Decisions should be made with cardiology and surgical teams

Question 35

When to screen for coronary disease preoperatively?

Answer 35

Abnormal ECG, History of coronary/valvular disease, Age >50 years with two or more risk factors

Question 36

What is RCRI?

Answer 36

Revised Cardiac Risk Index: estimate perioperative cardiac risk

Question 37

What are METs used for?

Answer 37

Assess functional capacity

Question 38

What does NYHA assess?

Answer 38

Assess how cardiac disease impacts daily activity

Question 39

What medications to continue preoperatively?

Answer 39

Beta-blockers and Statins if already prescribed

Question 40

What to hold preoperatively?

Answer 40

ACEIs/ARBs 24 hrs pre-op

Question 41

What defines high cardiac risk?

Answer 41

Major vascular surgery, emergent major operations, or long surgeries with major fluid shift

Question 42

What to do for unstable angina before surgery?

Answer 42

Postpone elective surgery until cardiac status is optimized

Question 43

Indicators of poor LV function?

Answer 43

EF <40%, LVEDP >18 mmHg, CI <2.2 L/min/m², Wall motion abnormalities

Question 44

What is the gold standard for assessing coronary issues?

Answer 44

Cardiac catheterization (coronary angiogram)

Question 45

What leads are used for ischemia monitoring?

Answer 45

Use Leads II, V4, V5

Question 46

What indicates ischemia?

Answer 46

Based on ST-segment changes

Question 47

What to do if treating pain is ineffective?

Answer 47

Consider Beta blockers

Question 48

What to monitor postoperatively in ICU or telemetry?

Answer 48

Low cardiac output, Arrhythmias, Ischemia, Stroke, Graft complications

Question 49

What to maintain postoperatively?

Answer 49

Normothermia, O₂ saturation >95%, Tight BP & glucose control

Question 50

When to resume clopidogrel post-op?

Answer 50

Resume ASAP if bleeding permits

Question 51

What to consider for low-risk patients post-op?

Answer 51

Early extubation in low-risk (EF >35%) 'fast-track' patients

Question 52

How to prevent post-op shivering?

Answer 52

Use meperidine

Question 53

What is the risk of re-MI within 30 days post-MI?

Answer 53

High risk of re-MI

Question 54

Student Question: Which of the following anesthetic agents is preferred for its cardioprotective effects in CAD patients? A) Desflurane B) Sevoflurane C) Ketamine D) Propofol

Answer 54

Correct Answer: B Rationale: Sevoflurane provides myocardial protection by improving coronary blood flow and reducing myocardial oxygen demand. Desflurane can increase sympathetic tone, which may lead to ischemia. Ketamine increases myocardial oxygen consumption, making it less favorable for CAD patients. (Source: Nagelhout et al., 2023, p. 547-548)

Question 55

Student Question: In patients with known Coronary Artery Disease (CAD), what is the most important anesthetic goal during the perioperative period? A) Increase heart rate to ensure adequate cardiac output B) Prioritize deep anesthesia over hemodynamic control to prevent awareness C) Optimize coronary perfusion by balancing oxygen supply and demand D) Avoid volatile agents to reduce the risk of myocardial depression

Answer 55

Correct Answer: C Rationale: The primary anesthetic goal in CAD patients is to maintain coronary perfusion pressure & adequate myocardial oxygen supply while minimizing oxygen demand. This is achieved by controlling heart rate, blood pressure, and contractility to prevent ischemia. (Source: Nagelhout et al., 2023, p. 546)

Question 56

Student Question: In a patient with CAD undergoing CABG, which set of ECG leads provides the highest sensitivity for detecting intraoperative myocardial ischemia? A) Leads I and aVR B) Leads II and III C) Leads II, V4, and V5 D) Leads aVL, V1, and V2

Answer 56

Correct Answer: C Rationale: CAD patients require continuous ischemia monitoring. Leads II, V4, and V5 are optimal for detecting ischemic changes. (Source: Nagelhout et al., 2023, p. 547-548)

Question 57

Student Question: Which of the following surgical procedures is most appropriately classified as high cardiac risk (>5%) according to ACC/AHA perioperative guidelines? A) Laparoscopic cholecystectomy in a stable patient B) Elective inguinal hernia repair under local anesthesia C) Emergent open abdominal aortic aneurysm (AAA) repair D) Cataract extraction with monitored anesthesia care

Answer 57

Correct Answer: C Rationale: Emergent major vascular procedures (like open AAA repair) involve significant hemodynamic shifts, bleeding risk, and surgical stress, making them high-risk for major adverse cardiac events (>5%). The other options are low to intermediate risk based on invasiveness and physiological demand. Source: (Nagelhout et al., Nurse Anesthesia, 7th ed., 2023, p. 196)

Question 58

Student Question: 4. Which of the following statements about perioperative myocardial infarction (MI) is most accurate? A) Most perioperative MIs present with classic chest pain and are easily recognized in real time B) Over 50% of perioperative MIs are silent, particularly in elderly and diabetic patients C) Perioperative MIs typically occur after hospital discharge and are rarely detected early D) Diabetic patients are less likely to develop perioperative MIs due to metabolic conditioning

Answer 58

Correct Answer: B Rationale: More than 50% of perioperative MIs are clinically silent, particularly in elderly and diabetic patients due to autonomic neuropathy or blunted pain perception. These silent MIs often present as subtle ECG changes or elevated troponin levels, which is why routine monitoring and cardiac biomarkers are critical post-op in high-risk patients. Options A, C, and D are incorrect or misleading and do not reflect evidence-based perioperative cardiac risk profiles. Source: (Source: Barash et al., 2022, p. 560)

Question 59

Student Question: What is the estimated mortality rate if a patient experiences a reinfarction in the perioperative period following a recent myocardial infarction (MI)? A) 10% B) 25% C) 50% D) 75%

Answer 59

Correct Answer: C Rationale: Patients who suffer a reinfarction (a second MI) during the perioperative period after a recent MI face a mortality rate of approximately 50%. This extremely high risk underscores the importance of timing surgery appropriately after MI, following guideline-recommended waiting periods and optimizing medical management. (Source: Nagelhout & Elisha, 2022, p. 353).