Lecture 9: Ischemic Heart Disease Part 1 Flashcards
What are the MC risk factors for ischemic heart disease?
- Genetic influences
- High-fat and energy rich diets
- Smoking
- Sedentary lifestyles
What is the #1 cause of myocardial ischemia?
Atherosclerotic coronary artery disease
What is the most important part of a blood vessel when it comes to blood flow?
The radius of the vessel.
What can affect the radius of a blood vessel?
- Atherosclerosis
- Vascular tone
- Endothelial cell dysfunction
What is the spectrum of IHD?
- Prinzmetal angina
- Stable angina
- Unstable angina
- MI
Prinzmetal is more unique
What IHD are considered ACS?
- Unstable angina
- MI
Needa treat asap!!!
Describe unstable angina, NSTEMI, and STEMI in terms of blood flow occlusion.
- Unstable angina = no occluded CORONARY blood flow
- NSTEMI = partially occluded coronary blood flow
- STEMI = completely occluded coronary blood flow
Unstable angina still has occluded blood flow through OTHER vessels.
How can we tell the difference between stable and unstable angina?
- No response to NTG = unstable
- Change in normal pattern of angina = unstable.
- Unstable = impending MI!!!!!!!!!!!!
At what point is damage irreversible to the myocardium?
Infarct stage.
Ischemia and injury are still reversible.
If we have an acute MI, how long has the infarct mostly likely been occurring?
< 3-5 days
What is a transmural infarct?
MI that extends through all 3 layers of the heart.
How does an NSTEMI typically appear on EKG?
- ST depression
- T-wave inversion
Generally subendocardial.
NSTEMIs are also known as subendocardial or non-q-wave MI.
Describe the 5 types of MIs.
- Primary coronary event (plaque)
- Secondary to ischemia (prinzmetal, embolism, HTN)
- Sudden unexpected cardiac death
- Coronary angioplasty or stent related (4a = PCI, 4b = stent thrombosis)
- CABG related
Just know type 4 means coronary intervention in general
What 3 demographics is silent ischemia most common in?
- Diabetics
- Elderly
- Women
What is myocardial stunning?
Reversible dysfunction following reperfusion.
Your heart stops working to try to preserve itself, but if you intervene, it will recover.
What is myocardial hibernation?
Ventricular dysfunction that will recover once reperfused.
Seen in a MUGA scan :)
What is the posterior descending artery typically a branch of?
The right coronary artery.
15% of the time, its left.
What can the SA nodal branch sometimes come off of?
40% of the time, it can come off the left circ.
Normally off the right coronary.
What is RaMP?
- Right coronary
- SA & AV nodes
- Marginal
- Posterior descending
What is LoCA?
- Left coronary
- Circumflex
- Anterior Descending (most often occluded)
What is this
Levine’s sign, AKA chest discomfort/angina pectoris.
Describe the typical clinical presentation of chest discomfort.
- Males > 50 or female > 60
- Episodic chest discomfort (2-5 mins)
- Often described as heaviness or pressure, not PAIN.
- Substernal/central (sometimes radiates)
- Sudden and constant
Severity does not always correlate with the extent of the injury.
What are the two primary alleviating factors of angina pectoris?
- NTG
- Rest
Why does chest discomfort tend to occur in the morning?
Cortisol levels rising overnight.
What is the concern with exercise stress tests in women?
It can be less accurate.
Women in general can have more vague symptoms.
What abnormal PE findings can suggest MI?
- HTN
- Anxious & diaphoretic
- New heart sounds/murmurs
- Labored breathing
- ALOC
It can also be perfectly normal :)
How do we treat prinzmetal angina?
- CCBs
- Nitrates
Who is prinzmetal angina MC in?
Middle-aged women
Mimics STEMI on EKG.
What illegal drug can induce vasospasms?
Cocaine
At minimum, if someone presents with possible ACS but nondiagnostic EKG, what must we do?
Obs for at least 12 hours!
What are the 3 ranges of heart scores?
- 0-3 = discharge
- 4-6 = admit for obs
- 7-10 = admit w/ early intervention
What are the 7 criteria for a TIMI score?
- Age >= 65
- > = 3 CAD risk factors
- Prior CAD (stenosis > 50%)
- ASA in last 7 days
- Severe angina (2+ episodes in past 24h)
- ST deviation on EKG (>= 0.5mm)
- Elevated cardiac biomarkers
Only used for unstable angina or NSTEMI.
0-2 = low
3-4 = intermediate
5-7 = high
What are the 5 criteria for a HEART score?
- History
- EKG
- Age
- Risk factors
- Troponin
0-2 for all criteria = max of 10.
What does a HEART score calculate?
Risk of major adverse cardiac event (MACE) in 6 weeks.
