Ischemic heart disease part 1 Flashcards
How common are heart attacks in US
someone has a heart attack every 40 seconds
how many heart attacks are silent
1 in 5
what are the MC risk factors for ischemic heart disease (IHD)
- genetics
- high fat and energy rich diet
- smoking
- sedentary lifestyle
what group is IHD growing among
low-income groups
what is the pathogenesis of IHD
the heart muscle is not perfused with blood leading to improper oxygenation and ischemic results.
(in notes)
what is the mechanism of myocaridal ischemia
very multifactoral but egnerally an imbalance between oxygen supply and demand.
what is oxygen supply determined by
blood flow which is regulated by pressure vs. resistance ratio
what is the most critical factor of blood flow and therefore oxygen supply
the radius of the blood vessel
what can influence the radius of the blood vessel
This is influenced by atherosclerosis hardening of vessels, vascular tone, and endothelial cell dysfunction in cardiac ischemia
what is the MCC of IHD
atherosclerosis (in notes slide 11)
what is considered a silent heart attack
found after the fact or incidentally due to symptoms not being indicative of myocardial infarction
(said in class)
what are the types of ischemic heart disease
- prinzmetal angina
- stbale angina
- unstable angina
- MI (stemi/nstemi)
what is included in acute coronary artery syndrome?
- unstable angina
- MI (stemi/nstemi)
flip to see a picture example of unstable, chronic stable and prinzmetal angina.
what is acute coronary syndrome
ACS results when there is plaque rupture and thrombus formation.
what determines the severity of ACS
the amount of coronary blood flow restriction
what are the three severity types of ACS
- unstable angina - no occluded blood flow in coronary vessels but unstable plaque is still present leading to symptoms at rest
- NSTEMI - partially impeded blood flow through the coronary vessels
- STEMI - completely impeded blood flow through the coronary vessels
what is STABLE angina?
- fixed stenosis!
- occurs when the heart is under stress and needs more oxygen (exercise, cold, emotions)
how long does STABLE angina typically last
- 1-15 minutes
- goes away with rest and/or NTG
- may continue without much change for years
(i assume this means it is intermittent!)
how does the pattern of unstable angina differ from stable angina
- unstable angina is unexpected and a change in your usual pattern of stable angina
- does NOT go away with nitroglycerin
- considered an EMERGENCY. wanring that an MI is impending
what is prinzmetal angina
spasm of the vessel leading to reduced vessel diameter or decreased pressure, like in hypotension, that leads to poor perfusion
(said in class and at bottom of slide 11)
after occlusion of a coronary artery, the myocardium involves through various stages and degrees of severity of impact. what are these stages?
- ischemia
- injury
- infarction
what is included in the ischemic phase of coronary artery occlusion
- Present as soon as there is a decrease or complete absence of blood supply to myocardial tissue
- Cardiac cells can tolerate mild-moderate anoxia for a short time without greatly affecting their function
- When adequate blood flow / reoxygenation return, these cells usually return to a normal
what occurs during the injury phase of coronary artery occlusion
- If ischemia is severe or prolonged, the anoxic cardiac cells sustain damage and stop functioning normally
- Damage to the cells still remains reversible so that injured cells remain viable and salvageable for some time
- Cells may return to normal or near normal after the return of adequate blood flow and reoxygenation
what is occuring in the infarction phase of coronary artery occlusion
- Severe myocardial ischemia continues because of continued complete absence of blood supply
- The anoxic cardiac cells will sustain irreversible injury and die.
- DEAD MEAT DONT BEAT
once ischemia occurs what physiologically happens to the heart
The tissue will no longer contract and will not have normal function leading to ventricular arrhythmias, heart failure, and sudden death
(in notes on slide 16)
what is the definition of myocardial infarction
irreversible myocardial injury resulting in necrosis of a portion of the myocardium
ACUTE MI suggests the infarction is how old?
<3-5 days
what is the most concerning type of infarct?
transmural infarcts due to the amount of cardiac dysfunciton that results
( in notes, slide 17)
what are the types of myocardial infarctions?
- subendocardial/NSTEMI/Non-Q Wave MI
- Transmural/STEMI/Q wave MI
what is involved in subendocardial/NSTEMI/ non Q wave MI
Involves small area in the subendocardial wall of the LV, ventricular septum, or papillary muscle
what causes subendocardial/NSTEMI/ non Q wave MI
Caused by a local decrease in blood supply from narrowing of a coronary artery. The subendocardial area is particularly susceptible to ischemia.
what would the EKG show for subendocardial/NSTEMI/ non Q wave MI
EKG → ST depression or T-wave inversion (or no EKG changes)
what is involved in transmural/STEMI/ Q wave MI
Extend through the whole thickness of the heart muscle wall
what is the cause of transmural/STEMI/ Q wave MI
Associated with atherosclerosic plaques in a coronary artery that cause complete occlusion
how is a transmural/STEMI/ Q wave MI labeled
Labeled by the wall involved: anterior, posterior, inferior, lateral, or septal
what would an EKG show for transmural/STEMI/ Q wave MI
EKG → STEMI → Q waves
Tombstoning = grave prognosis
what is the calssification of a Type 1 MI
Spontaneous MI related to ischemia due to a primary coronary event such as plaque erosion and/or rupture, fissuring, or dissection
what is the classification of Type 2 MI
MI secondary to ischemia due to either ↑ oxygen demand or ↓ decreased supply (e.g. coronary artery spasm, coronary embolism, anemia, arrhythmias, HTN, or hypotension)
what is the classification of type 3 MI
Sudden unexpected cardiac death, including cardiac arrest, often with symptoms suggestive of myocardial ischemia, accompanied by new ST elevation, or new LBBB, or evidence of fresh thrombus in a coronary artery by angiography and/or at autopsy, but death occurring before blood samples could be obtained, or at a time before the appearance of cardiac biomarkers in the blood
what is the classification of type 4 MI
MI associated with coronary angioplasty or stents
what is the classification of type 5 MI
MI associated with CABG
can you have atherosclerotic blockages with a type 2 MI
yes, but it is not typically the main tissue!
(in notes on slide 23)
What is silent ischemia and who is it most common in?
- Myocardial ischemia without discomfort or pain
- More common in diabetics, elderly patients, and women
what is myocardial stunning
- Reversible myocardial dysfunction following reperfusion of an ischemic insult
- Initially appears to be permanently damaged but following early reperfusion, contractile function returns to normal
what is hibernating myocardium
- A result of prolonged reduction in blood flow from coronary artery disease
- Causes ventricular contractile dysfunction that will improve once blood flow improves¹
how is hibernating myocardium typically discovered
Hibernating myocardium is typically discovered by Cardiology following a MUGA scan (Multigated Acquisition Scan), which is a nuclear imaging technique used to measure EF
(in notes bottom of slides 24)
Label this, itll come in handy
try to label this too
label it gurrrrl
labellll ittttt
what the actual heck is going on rn
mellert said:
what does the right coronary artery supply
- inferior wall LV
- Right ventricle
what is the significance of the right coronary artery in reference to MIs
assesses for inferior wall MIs. often accompanied by a ↓ HR because of involvement of the sinus node. Long term effects are usually less severe than those of an anterior wall MI.
what leads assess the Right coronary artery
II, III and aVF
what does the left anterior descending artery supply blood to
- septal wall
- anterior wall LV
what is the significance of the left anterior descending artery in reference to MIs
AWMI - the anterior wall performs the main pump function and decay of the function of this wall will lead to ↓ BP, ↑ HR, shock and on a longer term, HF
what is the EKG leads assessing Left anterior descending artery
V1-V4
what does the left circumflex artery supply
lateral wall LV
what EKG leads assess the left circumflex artery
I, aVL, V5, and V6
if your brain works like this it may be good to label this~!
what are the 2 questions to consider when initially evaluating a patient with suspected MI
- how likely is ACS?
- what is the risk of adverse events
what is the term used to describe chest discomfort related to IHD
angina pectoris
what is the typical patient presentation in MI
- male>50 or female>60
- episodic chest discomfort!
what is the description of the chest pain that occurs with typical angina pectoris
- quality - heavy, presssure, squeezing, smothering, aching, choking. rarely described as pain
- location - substernal, central.
- radiation to shoulder, jaw, shoulders/back
what is the duration of episodic chest discomfort in a typical MI patient
- Duration: 2-5 minutes, crescendo-decrescendo
- Setting: typically with exertion
- Severity: varies and may not correlated with extent of myocardial injury
what are aggravating and alleviating factors for a typical mI patient
- activity/exercise, meals, stress/strong emotion, cold, sex, morning time, supine position
- Alleviating - NTG, rest
what are associated S/Sx for MI patients
- SOB
- N/V
- diaphoresis
- fatigue
- weakness
- feeling of impending doom
- paresthesias
- dizziness
- fever
what are associated symptoms for women that are different from normal associated symptoms
- pressure/pain in lower chest/upper abdomen
- extreme fatigue
- lightheadedness
- fainting
- upper back pressure
what may be less accurate in women
exercise stress tests!
why are MIs so important to catch in women
Women are are more likely to die after their first heart attack
what are PE findings for MI
what are 2 big differentials for chest pain ( i dont usually memorize these, but for some reason this slide looks important)
- atheroscleosis (stenosis or plaque rupture)
- variant (prinzmetal) angina
what is the MC artery involved in variant (prinzmetal) angina
RCA
what is prinzmetal angina treated with
CCB and nitrates
who is prinzmetal angina MC in
middle aged women
what does prinzmetal angina look like on an EKG
mimics STEMI on EKG
what are diagnostic studies that could be done in a “chest pain” patient
- EKG ALWAYS
- cardiac biomarkers (almost always)
- stress testing
- coronary angiogram
- imaging
Prof mellert said this is super helpful becuase it contains everything from this lecture and the next lecture
what is the TIMI risk score (not on test but will be on PANCE)
TIMI (Thrombolysis in MI) Risk Score is used to risk stratify patients to help determine who should undergo aggressive evaluation / treatment. Event rates increase significantly as the TIMI risk score increases.
what is considered low, intermediate, and high risk TIMI score (not on test but will be on PANCE)
- 0-2: Low risk
- 3-4: Intermediate risk
- 5 or more: High risk
what are the 7 questions used in the TIMI risk score (not on test but will be on PANCE)
- Aged ≥ 65 years
- ≥3 CAD risk factors (HTN, DM, HLD, smoking, + FH early MI)
- Prior CAD (stenosis >50%)
- Aspirin in last 7 days
- Severe angina ( >2 anginal events within 24 hours)
- ST deviation on admission EKG ( >0.5mm)
- Elevated cardiac markers (CK-MB or troponin)
add 1 point for each of these
what is heart score (WILL BE ON TEST)
A risk assessment for major adverse cardiac events that can help decide whether to discharge, admit for observation, or admit w/ early invasive strategies.
what are the three categories of heart score and their interpretations.
- 0-3 -> risk 2.5% -> discharge
- 4-6 -> risk of 22.3% -> admit for obs
- 7-10 -> risk of 72.7% -> admit w/early invasive strategies
what are the 5 categories that determine heart score?
- History
- ECG
- Age
- Risk factors
- Troponin
“HEART” score
flip for another variation of heart score chart
she said this is breaking down what heart score stands for. HEART SCORE IS TESTABLE pleassssseeeee know this!
FLIP FOR DOGGOOOOO!!!! congrats on finishing another lecture!
