ICL 4.3: Clinical Chronic Ischemic Heart Disease Syndromes

Question 1

how does age effect CAD?

Answer 1

age is a powerful risk factor for CAD

80+ years old has 30% prevalence in men and 22% in women!

Question 2

what are the risk factors for CAD?

Answer 2

1. age
2. HTN
3. hyperlipidemia
4. cigarette smoking
5. DM

as you add risk factors, you increase prevalence and suspicion for CAD

Question 3

how does heart disease mortality compare to other causes of death?

Answer 3

heart disease is the number 1 cause of all age groups!!

in younger people, cancer has a higher risk but whatever

Question 4

what are the trends in heart disease mortality over the last 30 years?

Answer 4

statins and decreased smoking dropped heart disease a ton in 2000

Question 5

how is blood flow regulated in the coronary arteries?

Answer 5

the arterioles are the major site of resting resistance in the coronary circulation

Question 6

how does adenosine effect vessel size?

Answer 6

adenosine causes maximal vasodilation of the arterioles which leads to hyperemic blood flow

that means maximum blood flow/exercise conditions (4x blood flow!)

Question 7

what is the effect of coronary stenosis on resting and maximal coronary blood flow?

Answer 7

how much blood flow you have in the artery, under resting conditions, the drop occurs at ~90% stenosis or greater

how much blood flow you have in the artery, under maximal flow conditions, coronary flow drops off after a 70% stenosis

so 70% is the anatomical threshold where we expect that a stenosis would use symptoms in a person when they’re walking

Question 8

what is normal coronary blood flow?

Answer 8

resting coronary blood flow is about 225 mL/min

coronary blood flow (CBF) increases during exercise

during systole, there’s compression of the coronary arteries by the myocardium so most of the coronary blood flow happens during diastole which is rare!! all other arteries have blood flow during systole

Question 9

what is the effect of coronary stenosis on exercise?

Answer 9

under exercise conditions, systolic blood flow goes up a bit but diastolic blood flow goes up a lot due to vasodilation of the arterioles i response to adenosine which regulates coronary blood flow

in healthy patients, there should be a 4 fold increase in coronary blood flow and supply vs demand are well matched

with a coronary conditions, during resting conditions you’re probably okay but during exercise conditions you can’t increase diastolic blood flow and there’s a supply vs demand mismatch which leads to symptoms like angina

Question 10

what’s the difference between acute coronary syndromes and stable angina?

Answer 10

ACS = STEMI, NSTEMI, or unstable angina

in contrast, stable angina chest pain or tightness or other symptoms such as shortness of breath and fatigue/exercise intolerance, that occurs with exertion and is relieved by rest and is due to CAD

Question 11

where is the pain in coronary artery disease?

Answer 11

1. chest pain
2. jaw pain
3. upper abdominal pain
4. neck pain
5. radiation to the arms (can be both!)

pain presentation varies!

Question 12

what are branches of the LCX called?

Answer 12

obtuse marginals

Question 13

what are branches of the LAD called?

Answer 13

diagonals

Question 14

what is the approach for asymptomatic CAD patients?

Answer 14

For asymptomatic patients, focus on primary and secondary prevention of MI with medical and lifestyle intervention:

1. aspirin
2. statin
3. HTN control
4. DM control
5. smoking cessation
6. diet
7. exercise

Question 15

what is the approach for symptomatic CAD patients?

Answer 15

for symptomatic patients, we do lifestyle interventions plus we do stress testing or other procedures to identify if symptoms are due to CAD and to provide appropriate treatment

Question 16

what are the typical symptoms of CAD?

Answer 16

1. chest pain (pressure, squeezing, ache)
2. SOB
3. fatigue
4. exercise intolerance

not everyone will have all these symptoms! they might just have SOB

Question 17

what is primary prevention?

Answer 17

prevention of a disease or a disease event (for example, myocardial infarction or stroke), in a person with no known evidence of this disease

for example: someone is at risk for MI due to hypertension and diabetes – they are treated for reduction of the risk of MI, even though they have not been diagnosed with CAD –> this is called primary prevention

Question 18

what is secondary prevention?

Answer 18

prevention of a disease or disease event (for example, myocardial infarction or stroke), in a person who has been diagnosed with a disease and/or had a symptomatic event due to that disease

for example: someone has an MI and is treated and recovers; now that person’s medical treatment is considered “secondary prevention” of MI

Question 19

what is a stress test?

Answer 19

you can either do it via:
1. exervise

2. pharmacological = dobutamine or lexicon (a form of adenosine)

then pick an imagining method:
1. no imagining, EKG only

2. nuclear imaging
3. echocardiogram

Question 20

what are the various names for stress testing for CAD?

Answer 20

1. stress echo
2. stress test
3. nuclear stress test
4. treadmill stress test
5. lexiscan nuclear stress test
6. myocardial perfusion imaging

Question 21

nuclear myocardial perfusion imaging?

Answer 21

slide 24

go look at the picture….

Question 22

what is a reversible defect in relation to nuclear myocardial perfusion imaging?

Answer 22

“Reversible defect” means a defect is present on stress imaging that was not present on rest imaging; this is consistent with CAD with significant stenosis

Question 23

what is the newer alternative to stress testing?

Answer 23

coronary CT-angiography

coronary CTA is equivalent to stress testing for the assessment of patients with chest pain

but you have to use IV contrast so you have to have creatinine < 1.5 so the patient can safely receive IV contrast without effecting renal function

Question 24

what are the 2 major goals in treatment of stable angina?

Answer 24

1. reduction of MI risk and risk of death = help them live longer
2. reduction of symptom burden = help them feel better

Question 25

what medications would you give to help reduce MI risk and death risk in a patient with CAD?

Answer 25

1. 81 mg aspirin failure
2. high intensity statin therapy

atorvastatin 40-80 mg faily

or

rosuvastatin 20-40 mg daily)

Question 26

what medications would you give to help reduce symptom burden in a patient with CAD?

Answer 26

anti-anginal medical therapy

1. Beta blocker: metoprolol or carvedilol
2. long-acting nitrates: isosorbide, indor
3. calcium channel blocker: amlodipine
4. ranolazine

Question 27

what are the 2 methods of revascularization in patients with CAD? how do you chose which one to do?

Answer 27

1. PCI
2. CABG

these are for symptomatic patients, revascularization can provide benefit

BUT if they’re asymptomatic, use medicaitons and lifestyle changes as first line approach!!

for severe, symptomatic CAD with “Triple vessel CAD” or left main disease: typically treated with CABG

for severe, symptomatic CAD with all other CAD anatomy like single vessel or double vessel, typically treated with PCI

Question 28

what is PCI?

Answer 28

PCI = percutaneous coronary intervention

aka a stent

Question 29

what is a CABG?

Answer 29

CABG = coronary artery bypass graft surgery

3 major options for the bypass conduit:
1. saphenous vein graft

2. radial artery
3. LIMA = left internal mammary artery

Question 30

what is fractional flow reserve?

Answer 30

when assessing coronary artery stenosis, the most common method for determining severity is visual estimation on coronary angiogram – this method is quick and commonly utilized, but has some limitations including:

1. inter-observer variability
2. over- or under- estimation of true stenosis severity
3. limitations of two dimensional angiogram pictures to represent a three dimensional reality

so an additional method to measure the severity of a coronary artery stenosis is called FFR or intracoronary physiology

FFR = distal coronary pressure /proximal coronary pressure done under maximum hyperemia – this is done by giving adenosine

Question 31

what should your FFR be?

Answer 31

FFR cutpoint for significant ischemia is FFR ≤ 0.80

significant means that there is enough of a reduction of blood flow that there’s probably symptoms and you should treat with PCI or CABG

if FFR is 0.85 to 0.95, then you only do medical therapy

Question 32

what is iFR?

Answer 32

iFR = instantaneous wave free ratio

similar concept to FFR, but it does not require hyperemia! so it’s done at resting heart rate which saves time and effort and potential symptomatic problems

iFR is only during diastole

it’s used more and more frequently for assessment of CAD severity and decision making in the cath lab

Question 33

what is a normal iFR?

Answer 33

iFR cutpoint: ≤ 0.89

Question 34

A 72 year old male with a history of hypertension, hyperlipidemia (LDL cholesterol 160 mg/dL) and poorly controlled type 2 diabetes mellitus (HbA1c 9.7%) presents to you for evaluation.
He reports chest pain after walking 2-3 blocks or sometimes after a big meal. His describes the pain as “pressure” and sometimes feels an ache in his left arm at the same time. These symptoms usually last for 5-10 minutes and resolve with rest.

How would you classify his description of his chest pain:

A) typical angina

B) atypical angina

C) non-cardiac chest pain

D) pleuritic chest pain

Answer 34

A) typical angina

Question 35

A 72 year old male with a history of hypertension, hyperlipidemia (LDL cholesterol 160 mg/dL) and poorly controlled type 2 diabetes mellitus (HbA1c 9.7%) presents to you for evaluation.
He reports chest pain after walking 2-3 blocks or sometimes after a big meal. His describes the pain as “pressure” and sometimes feels an ache in his left arm at the same time. These symptoms usually last for 5-10 minutes and resolve with rest.

How would you estimate his pre-test probability for CAD?

A) 10%
B) 30%
C) 50%
D) 80%

Answer 35

D) 80%

multiple risk factors for CAD:

1. age
2. HTN
3. hyperlipidemia
4. DM

typical description of angina

Question 36

You diagnose CAD. You want to start optimal medical therapy for CAD. Which of the following is not part of optimal medical therapy for CAD?

A) Aspirin
B) Atorvastatin
C) Metoprolol
D) Amiodarone

Answer 36

D) Amiodarone = antiarrhythmic drug for afib or ventricular tachycardia

optimal medical therapy for CAD:
1. antiplatelet therapy: Aspirin

2. high-intensity statin therapy:
   Atorvastatin or Rosuvastatin
3. Beta-blocker: metoprolol
4. second anti-anginal medication:
   long-acting nitrate, Ranolazine, or CCB

Question 37

You diagnose CAD. You start optimal medical therapy for CAD. Which treatment is associated with a reduction in the risk of mortality from CAD?

A) Imdur
B) Atorvastatin
C) Metoprolol
D) Ranolazine

Answer 37

B) Atorvastatin

statins are what reduce mortality the most

the others are used for symptom benefits

Question 38

A 65 yo female with a history of HTN and Diabetes presents for evaluation due to chest pain. She describes burning chest pain with radiation to the neck and jaw. You started medical therapy for CAD but she returns with ongoing chest pain symptoms. You decide to proceed with coronary angiogram. At angiogram, an intermediate severity (60-70%) stenosis of the LAD is identified. The RCA and LCX have only mild disease. You then perform FFR and measure an FFR value of 0.72. What is the next step in the management of this patient?

A) Proceed with PCI since the FFR proves that the stenosis is causing ischemia

B) Finish the procedure and treat with medical therapy only since the FFR proves that the stenosis is not causing ischemia

C) Finish the procedure and then order a coronary CTA for further evaluation

D) Consult CT surgery and refer for CABG

Answer 38

A) Proceed with PCI since the FFR proves that the stenosis is causing ischemia