Cardiac Imaging Flashcards
What are the indictions for EKG?
- cp, palpitations, fatigue/sob, syncope, seizure
- evaluate for aarrythmia, murmur, electrolyte imbalance, PE, CHF, cardiomyopathy, poisonings/electrocution
- drug monitoring
- check for defibrillator, pacemaker
What is the ASCVD risk score?
What is a good or bad score?
ASCVD is a 10 year CVD risk rating
Below 7.5% is low risk
Equal to or Above 7.5 is elevated risk
What can an EKG help diagnose?
- MI or potential CVD
- Detect arrythmias
- PE
- Enlargement of ventricles
- electrolyte disturbances
- drug effects on the heart
What is the electrical pathway of the heart? (
SA node –> internodal pathway –> AV node –> bundle of his –> left and right bundle branches –> purkinje fibers
What are the indications for stress testing?
- new cp or angina
- new hf of cardiomyopathy
- pre-op for patients with known cardiac conditions
- known cad and new or worsening sx
- valvular heart disease
- to assess heart health prior to new exercise regime or cardiac rehab
- hx of pci or revascularization) more than 5 yrs after CABG and 2 yers after pci if asx
ABSOLUTE contraindications to stress testing? (11)
- acute MI within 48 hrs
- acute myocarditis or pericarditis
- rapid afib or ventricular arrhythmias
- sx severe AS
- severe anemia, acute illness, infx
- uncontrolled hyperthyroidism
- acute aortic dissection, PE, recent CVA
RELATIVE contraindications
- Hypertrophic obstructive cardiomyopathy
- suspected left main diseases (greater than 50%)
- severe htn (200/110)
- chf
- severe ST depression at rest
- permanent pacemakers/LBBB
What type of imaging needed for pharmacologic stress test?
always nuclear or echocardiogram imaging
When is pharmacologic stress test indicated?
If the patient is not able to exercise adequately to achieve 85% of the age-predicted max heart rate
OR
when beta-blockers or other AV blocking agents inhibit the heart rate increase needed
What vasodilators are used for pharm stress test?
- lexiscan (best tolerated)
- adenosine
- dipyridamole (used less frequently)
Contraindications:
- significant reactive airway disease (asthma)
- significant hypotension
- high degree AV block
- unstable or complicated ACS
What is troponin?
a protein found in cardiac and skeletal muscle that helps with contraction
When is troponin detectable?
When does troponin peak?
2-4 hours after cardiac injury
Peaks at 12 hours
When is troponin released?
It’s released when the muscle cells are damaged
What is the ACC/AHA definition of ACS?
“A group of clinical syndromes compatible with acute myocardial ischemia”
What is the physiologic definition of ACS?
Plaque rupture leading to thrombus formation, leading to partial or complete blockage of coronary artery with or without myocyte death
What are differentials for chest pain?
Cardiac vs non cardiac
- angina vs ACS
- PE
- Pericarditis
- costochondritis
- GERD
- aortic dissection
- PNA
- CHF
What are the ASCVD risk categories?
under 5% – low risk
5-7.5% – borderline risk
7.5–20% – intermediate riks
above 20% – high risk
What should cholesterol levels be at?
LDL under 100
Total cholesterol 125 to 200
What factors are included in ASCVD risk calculation?
Age
Sex
Race
BP
Total cholesterol, HDL, LDL
Hx of diabetes
Smoker (yes, no, former)
On HTN tx?
On a statin?
On aspirin?
What is VLDL and what does it do?
Very low density lipoprotein
It carries mainly triglycerides
What are triglycerides?
What do they do?
What is a healthy number?
- Triglycerides are fatty acid chains that are transported to tissues for energy.
- Unused calories are converted into triglycerides for storage in fat cells
- Triglycerides increases LDL, decreases HDL
- Healthy triglycerides = under 150
How is non-HDL cholesterol calculated?
Total cholesterol - HDL = Non HDL
How to check for re-infarction or occlusion pots coronary intervention?
WHY??
Check CK-MB
Troponin stays elevated longer (back to baseline 7-14 days), so it’s hard to know if a new infarct has occurred.
CK-MB is not as sensitive a cardiac marker, but returns to baseline numbers within 48-72 hrs, so if there has been a new infarct, an elevated CK-MB would be the way to identify it.
What does INOCA mean?
What does MINOCA mean?
INOCA: Ischemia with non-obstructive coronary disease
MINOCA: MI with non-obstructive coronary arteries
- more common in women, younger, black or hispanic/latinx
- accounts for up to 14% of MIs
- underlying etiologies: spontaneous artery dissection, plaque rupture, erosion, clot resolved before cath, microvascular angina (syndrome x), coronary artery vasospasm (variant angina or prinzmetal angina)
