STEMI / NSTEMI Flashcards
STEMI
Occlusion of a coronary artery that is found with positive Cardiac marker labs (Troponin, CK-MB, and myoglobin) as well as ST-segment elevation on ECG.
Sudden interruption of blood flow to myocardium; most common cause is arteriosclerotic heard disease (ASHD); cocaine use associated with acute myocardial infarction (spasm); may lead to conduction abnormalities, ventricular aneurysms or decreased cardiac output; necrosis follows occlusion usually within 4 ‐ 6 hours
NSTEMI or Non-Stemi
Occlusion of a coronary artery that is found with positive Cardiac marker labs (Troponin, CK-MB, and myoglobin) with NO ST-segment elevation on ECG.
STEMI Pathophysiology
Sudden interruption of blood flow to myocardium; most common cause is arteriosclerotic heard disease (ASHD); cocaine use associated with acute myocardial infarction (spasm); may lead to conduction abnormalities, ventricular aneurysms or decreased cardiac output; necrosis follows occlusion usually within 4 ‐ 6 hours.
ST Segment Elevation occurs when there is insufficient collateral circulation to supply oxygen to the myocardium.
NSTEMI Pathophysiology
coronary arterial atherosclerotic plaque rupture or erosion & subsequent platelet aggregation/thrombus formation,
leads to subtotal occlusion of the involved artery. In an occasional patient, total thrombotic occlusion of the artery
leads to NSTE ACS rather than to ST segment elevation MI when extensive collateral blood supply perfuses the region of myocardium that is distal to the occluded artery.
STEMI/NSTEMI Epidemiology
Coronary heart disease causes about 1 of every 6 deaths in the United States or about 380,000 deaths per year.
635,000 Americans are diagnosed with a first MI,
230,000 have a recurrent MI,
150,000 more have a silent first MI.
1 American suffers a coronary event approximately every 30 seconds, and one dies from one every minute.
5 million+ people visit the ED in the US each year for evaluation of chest pain and related s/s
about 680,000 are dx with an acute coronary syndrome or NSTEMI
The presence of ST elevation or new left bundle branch block (LBBB) on the ECG distinguishes requiring consideration of immediate reperfusion (recanalization) CATH LAB
STEMIs accounts for about 30% of all MIs.
Key Symptoms of STEMI and NSTEMI
May have associated severe pain/pressure, SOB, diaphoresis, nausea. Caused by complete vessel occlusion, resulting in
transmural myocardial necrosis. ST-Segment. Elevation on ECG. Elevated cardiac biomarkers will usually follow, but are not necessary for diagnosis and initial treatment
Associated with anxiety, nausea, vomiting, restlessness, dyspnea, diaphoresis; occasionally painless (elderly, diabetics); S3 Or S4 gallop, new murmur. Chest pain Radiation to: left arm, jaw, back, and neck Mimics heartburn N & V Dyspnea Lightheadedness Diaphoresis Anxiousness Palpitation LOC *Women present with more unusual sx such as the nausea, indigestion, and vomiting. Some pts may be completely asymptomatic. This is known as a silent MI
Key Symptoms of NSTEMI
Associated with anxiety, nausea, vomiting, restlessness, dyspnea, diaphoresis; occasionally painless (elderly, diabetics); S3 Or S4 gallop, new murmur. Chest pain Radiation to: left arm, jaw, back, and neck Mimics heartburn N & V Dyspnea Lightheadedness Diaphoresis Anxiousness Palpitation LOC *Women present with more unusual sx such as the nausea, indigestion, and vomiting. Some pts may be completely asymptomatic. This is known as a silent MI
Physical exam findings in STEMI
NO physical exam findings are diagnostic or pathognomonic of an acute MI. Findings are typically normal or nonspecific. Watch for signs of L and R sided heart failure and signs of peripheral profusion.
Physical Exam Findings in NSTEMI
NO physical exam findings are diagnostic or pathognomonic of an acute MI. Findings are typically normal or nonspecific. Watch for signs of L and R sided heart failure and signs of peripheral profusion.
Acute vs. Chronic presentation of STEMI
Early Acute – begins minutes and lasts hours. T-wave will increase amplitude and widen over the area of the injury. ST segment line changes into the T-wave, which will look like a tombstone. Other causes of ST segment elevation must be included.
Evolved Acute Phase – the ST segment elevation begins to regress. T waves in leads w/ ST segment elevation will become inverted and the Q or QS waves become fully developed. (> 0.03s duration or depth)
Chronic Phase – Resolution of ST segment is variable. This normally resolves w/ in 2 weeks of an inferior infarction
U wave will be present on ECG
Acute vs. Chronic presentation of NSTEMI
Acute issue.
chronic issues may arise due to myocardial death
Differential Diagnosis of MI (both STEMI AND NSTEMI)
STEMI
- Acute Pericarditis
- Acute Myocarditis
- Stress Induced Syndrome (Takotsubo’s)
- Early Repolarization
NSTEMI
- aortic dissection
- pericarditis
- GI diseases
- The history
Diagnostics studies for MI (both)
- ECG – to differentiate between a STEMI and NSTEMI.
- Lab work including Troponin, CK-MB, and CBC.
- Lipid Panels to determine need for medications to reduce cholesterol
- Percutaneous Coronary Intervention via catheterization lab for the pt w/ recurrent anginal sx (for STEMIs - NSTEMIs will have further evaluation and labs on the floor to determine the necessity of a Cath and/or stent placement.
Genetics in diagnosis and management
Strong family hx of heart disease and MI increase risk of MIs
Signs and symptoms of MI
Associated with anxiety, nausea, vomiting, restlessness, dyspnea, diaphoresis; occasionally painless (elderly, diabetics); S3 Or S4 gallop, new murmur. Chest pain Radiation to: left arm, jaw, back, and neck Mimics heartburn N & V Dyspnea Lightheadedness Diaphoresis Anxiousness Palpitation LOC *Women present with more unusual sx such as the nausea, indigestion, and vomiting. Some pts may be completely asymptomatic. This is known as a silent MI
Diagnosis of MI (both)
STEMI
Using hx, and EKGs in an acute setting. Lab work and CXR will aid diagnosis as well.
Pt will have :
1. ST elevation seen on EKG
2. Positive cardiac marker labs (Troponin, CK-MB)
NSTEMI
Hx given by patient w/ positive findings and family hx, AND Positive Cardiac Marker Lab results (Troponin, CK-MB, BNPs)
