ICL 4.3: Clinical Chronic Ischemic Heart Disease Syndromes Flashcards
how does age effect CAD?
age is a powerful risk factor for CAD
80+ years old has 30% prevalence in men and 22% in women!
what are the risk factors for CAD?
- age
- HTN
- hyperlipidemia
- cigarette smoking
- DM
as you add risk factors, you increase prevalence and suspicion for CAD
how does heart disease mortality compare to other causes of death?
heart disease is the number 1 cause of all age groups!!
in younger people, cancer has a higher risk but whatever
what are the trends in heart disease mortality over the last 30 years?
statins and decreased smoking dropped heart disease a ton in 2000
how is blood flow regulated in the coronary arteries?
the arterioles are the major site of resting resistance in the coronary circulation
how does adenosine effect vessel size?
adenosine causes maximal vasodilation of the arterioles which leads to hyperemic blood flow
that means maximum blood flow/exercise conditions (4x blood flow!)
what is the effect of coronary stenosis on resting and maximal coronary blood flow?
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
what is normal coronary blood flow?
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
what is the effect of coronary stenosis on exercise?
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
what’s the difference between acute coronary syndromes and stable angina?
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
where is the pain in coronary artery disease?
- chest pain
- jaw pain
- upper abdominal pain
- neck pain
- radiation to the arms (can be both!)
pain presentation varies!
what are branches of the LCX called?
obtuse marginals
what are branches of the LAD called?
diagonals
what is the approach for asymptomatic CAD patients?
For asymptomatic patients, focus on primary and secondary prevention of MI with medical and lifestyle intervention:
- aspirin
- statin
- HTN control
- DM control
- smoking cessation
- diet
- exercise
what is the approach for symptomatic CAD patients?
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
what are the typical symptoms of CAD?
- chest pain (pressure, squeezing, ache)
- SOB
- fatigue
- exercise intolerance
not everyone will have all these symptoms! they might just have SOB
what is primary prevention?
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
what is secondary prevention?
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
what is a stress test?
you can either do it via:
1. exervise
- pharmacological = dobutamine or lexicon (a form of adenosine)
then pick an imagining method:
1. no imagining, EKG only
- nuclear imaging
- echocardiogram
what are the various names for stress testing for CAD?
- stress echo
- stress test
- nuclear stress test
- treadmill stress test
- lexiscan nuclear stress test
- myocardial perfusion imaging
nuclear myocardial perfusion imaging?
slide 24
go look at the picture….
what is a reversible defect in relation to nuclear myocardial perfusion imaging?
“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
what is the newer alternative to stress testing?
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
what are the 2 major goals in treatment of stable angina?
- reduction of MI risk and risk of death = help them live longer
- reduction of symptom burden = help them feel better
what medications would you give to help reduce MI risk and death risk in a patient with CAD?
- 81 mg aspirin failure
- high intensity statin therapy
atorvastatin 40-80 mg faily
or
rosuvastatin 20-40 mg daily)
what medications would you give to help reduce symptom burden in a patient with CAD?
anti-anginal medical therapy
- Beta blocker: metoprolol or carvedilol
- long-acting nitrates: isosorbide, indor
- calcium channel blocker: amlodipine
- ranolazine
what are the 2 methods of revascularization in patients with CAD? how do you chose which one to do?
- PCI
- 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
what is PCI?
PCI = percutaneous coronary intervention
aka a stent
what is a CABG?
CABG = coronary artery bypass graft surgery
3 major options for the bypass conduit:
1. saphenous vein graft
- radial artery
- LIMA = left internal mammary artery
what is fractional flow reserve?
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:
- inter-observer variability
- over- or under- estimation of true stenosis severity
- 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
what should your FFR be?
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
what is iFR?
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
what is a normal iFR?
iFR cutpoint: ≤ 0.89
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
A) typical angina
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%
D) 80%
multiple risk factors for CAD:
- age
- HTN
- hyperlipidemia
- DM
typical description of angina
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
D) Amiodarone = antiarrhythmic drug for afib or ventricular tachycardia
optimal medical therapy for CAD:
1. antiplatelet therapy: Aspirin
- high-intensity statin therapy:
Atorvastatin or Rosuvastatin - Beta-blocker: metoprolol
- second anti-anginal medication:
long-acting nitrate, Ranolazine, or CCB
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
B) Atorvastatin
statins are what reduce mortality the most
the others are used for symptom benefits
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
A) Proceed with PCI since the FFR proves that the stenosis is causing ischemia
