Acute Coronary syndromes Flashcards
Describe findings of a STEMI ) inc findings, ecg, hs-Tnl and CK
Patients presenting with cardiac-sounding chest pain
With persistent ST segment elevation (or new LBBB) on their ECG. ST elevation should be > 1 mm in limb leads and 2 mm in chest leads.
Subsequent hs-TnI will frequently be > 100 ng/L
(and CK usually > 400).
Describe findings of a N-STEMI inc findings, ecg, hs-Tnl
Patients presenting with cardiac-sounding chest pain.
ECG may show ST segment depression, T wave inversion or may be normal.
Subsequent hs-TnI will frequently be > 100 ng/L.
Previously established ECG changes such as old MI, LV hypertrophy or atrial fibrillation may be present.
Describe findings of unstable Angina inc findings, ecg, hs-Tnl
Patients presenting with cardiac-sounding chest pain.
ECG may show ST segment depression, T wave inversion or may be normal.
Subsequent hs-TnI will be within the normal reference range.
Describe Troponin levels in relation to Myocardial damage (+ how they might appear for males/ females)
TnI levels begin to rise 3 to 4 hours after myocardial damage and stay elevated for up to two
weeks. CK should also be measured in STEMI patients.
Males: hs-TnI levels greater than 34 ng/L for men suggests a high likelihood of myocardial
necrosis.
Females: hs-TnI levels greater than 16 ng/L for women suggests a high likelihood of myocardial necrosis.
troponin info —
Levels five-fold above the upper limit have a very high predictive value for type 1 myocardial infarction (>90%). Elevations up to three times the upper limit have limited predictive value (50-60%) and can be associated with many other conditions.
What do rising and falling cardiac troponin levels indicate
Rising and/or falling cardiac troponin levels differentiate acute from chronic cardiomyocyte damage (the more pronounced the change, the higher the likelihood of acute MI). A rise greater than 5 ng/L may indicate ACS.
When is hs-Tnl taken on admission (and how many more times thereafter)
In order to achieve a quick diagnosis we recommend a hs-TnI level is taken on admission and again at 1 hour.
Only one hs-TnI level is required if the onset of symptoms was 3 or more hours previously. If there is uncertainty, a further sample can be taken a further 2 hours later (3 hours after the first). Second hs-TnI levels can be useful to assess whether the elevation is static, rising or falling.
Describe as many instances as possible where they will be false positive elevation of hs-TnI
False positive elevation of hs-TnI in patients with advanced renal failure, large pulmonary embolism.
Occasionally, elevated hs-TnI may be seen in patients with severe congestive cardiac failure and in myocarditis and following prolonged tachyarrhythmias. Other conditions in which hs-TnI may be elevated are aortic dissection, aortic stenosis, hypertrophic cardiomyopathy, Takotsubo cardiomyopathy, malignancy, stroke and severe sepsis. Generally, hs-TnI levels do not seem to rise in the majority of patients who have undergone cardioversion. Hs-TnI levels may remain elevated for several days and care should be taken in their interpretation in the context of re-admissions within a couple of weeks of a myocardial infarction. A couple of serial hs-TnI levels will help by determining whether the level is falling (older event) or rising (recent event).
What are the diagnostic features of STEMI on egg
STEMI: ST elevation in 2 or more leads from the same zone (ie leads II, III or AVF as inferior leads) or presence of LBBB (left bundle branch block).
ST depression confined to leads V1 to V4 may have true posterior myocardial infarction and should be treated in the same manner as STEMI.
All patients should routinely have POSTERIOR (V7 - V9 below) and RIGHT VENTRICULAR LEADS recorded ON OR SOON AFTER ADMISSION, especially those with inferior STEMI, as diagnostic changes may be transient. ST elevation in RV4 is highly sensitive for right ventricular infarction.
photo for prev card
in workbook cardiology
Certain conditions may mimic STEMI on the ECG. (4) - and how?
- Early repolarisation causes up-sloping ST elevation, particularly in leads V1 and V2 (and sometimes V3). It is seen more commonly in younger, especially athletic patients. It is also seen in some Afro-Caribbean’s.
- There may be concave ST elevation in pericarditis and the ST changes may be very widespread.
- Brugada syndrome may also be misdiagnosed as anterior STEMI.
- Takotsubo cardiomyopathy (stress reaction mostly middle aged females) can also mimic STEMI and NSTEMI.
what are the 4 main management steps (immediate) for STEMI
- IV Access
- Pain relief (morphine and anti-emetic)
- Oxygenation (only if hypoxic and aim Sats > 94%)
- Asprin (300mg loading followed by 75mg od for life)
Use of Prasugrel for STEMI - action, who to use for, loading dose and ongoing period of use,
Prasugrel (thienopyridine inhibits ADP receptors 60 mg loading and 10 mg daily for up to 12 months, use is restricted to patients undergoing primary percutaneous coronary intervention (PPCI) for STEMI who are under the age of 75 and who weigh more than 60kg and who have not had a prior TIA or stroke.
Use of Clopidogrel for STEMI - action, who to use for, loading dose and ongoing period of use,
Clopidogrel (inhibits ADP receptors, loading dose 600 mg followed by 75mg od for up to 12 months for patients who do not fulfil criteria above for Prasugrel).
Use of Ticagrelor for STEMI - action, who to use for, loading dose and ongoing period of use,
Ticagrelor (non thienopyridine loading dose 180mg followed by 90mg bd for up to 12 months, used in patients who cannot have Prasugrel or as first choice NSTEMI)
