Condition 1 Flashcards
Definition for Acute coronary syndrome
ACS refers to any group of symptoms attributed to obstruction of the coronary arteries and also includes ST elevation MI, non-ST elevation MI, unstable angina
What does the history, ECG and troponin level of unstable angina show?
inc frequency of angina, unpredictable or at rest, chest pain < 20min
ECG - normal, ST depression or T wave changes
Troponin - normal
What does the history, ECG and troponin level of NSTEMI show?
chest pain > 20 minutes
ECG - ST depression or T wave inversion
Troponin - inc
What does the history, ECG and troponin level of STEMI show?
chest pain > 20 mins
NSTEMI + ST inc (>2mm in 2 consective chest leads or > 1mm in 2 limbs leads)
troponin - inc
how common is acute coronary syndrome
5/1000 for STEMI
What are the causes of acute coronary syndrome
atherosclerosis –> narrowing of coronary artery –> cardiac-oxygen needs are still met –> on exertion caric-oxgen needs no longer met –> MI –> chest pain –> stable angina
rupture of atherosclerotic plaque –> platelets stimulated –> thrombolysis –> more frequent and severe pain –> unstable angina
thrombus forms –> occlude artery –> myocardial infraction
if thrombus move and block downstream = NSTEMI/unstable angina
100% block = infract = STEMI
RF for ACS
same for atherosclerosis as well as outflow obstruction eg aortic stenosis or hypertension obstructive myopathy
symptoms for ACS
chest pain - central > 20 mins, often unresponsive to GTN radiates to neck and down left arm
nausea, sweating, dyspnoea, palpitations
elderly may present atypical symptoms of dyspnoea, fatigue, syncope, epigastric pain, pul oedema, acute confusion state, stroke, diabetic hyperglycaemic attacks, oliguria
signs on exam for ACS
distress, pallor, sweaty, tachycardia/bradycardia, BP changes, 4th heart sound
differential for ACS
stable angina (pain on exertion relieved by rest)
acute pericarditis (burning/sharp pain, radiate to neck/shoulders worse on coughing/breathing/lying down)
GORD (meals related)
aortic dissection (pain migrates down aorta, no ecg changes, syncope if associated with pericardial tamponade
myocarditis (stabbing chest pain, systemic symptoms)
PE - acute breathlessness, dizziness/syncope, pleuritic chest pain
further investigation for ACS
ECG - 20% normal, STEMI - STE, Q wave, new LBBB, tall T waves, NSTEMI - inverted T waves
biochemical markers
- creatinine-kinase MB (not used now)
- cardiac troponin most sensitive and specific, level inc within 3-12 hrs onset of chest pain)
- myoglobin not v. specific , level inc within 1-4 hrs
CXR - cardiomegaly, PE, widened mediastinum (aortic rupture)
management for ACS
risk stratification -Thombolysis in Myocardial Infraction s (TIMI) score or Global Registry of acute coronary event (GRACE)
initial risk - determined by complications of the acute throbosis
long-term risk - defined by clinical risk factors eg age, prior-MI or bypass surgery, diabetes, HF etc
high risk pts - for progression to MI or death require urgent coronary angiography
low risk pts - manage with aspirin, clopidogreal, beta-blockers and nitrates
what are the immediate treatment for ACS
ROMANCE
reassure oxygen - maintain sats >94% 2-4L/min Morphine Aspirin Nitrates - GTN spray or buccal etc C - clopidogrel Enoxaprin/Fondaparinux ECG
What are treatment for NSTEMI
beta blocker (atenolol)
fondaparinux
nitrates
high risk pts - GP IIb/IIIa antagonist, consider clopidogrel in additon to aspirin for 12 months
low risk pts - discharge if repeat troponin is -ve
definition of angina pectoris
a clinical syndrome of chest pain that accompanies periods of myocardial ischaemia
how common is angina pectoris
> 1.4 million ppl in the UK ie very common
causes for angina
atherosclerosis –> narrowing of coronary artery –> cardia-oxygen needs are still met –> on exertion cardiac - oxygen needs are no longer met –> MI –> chest pain –> stable angina
Rupture of atherosclerotic plaque platelets stimulated thrombolysis more frequent and severe pain Unstable Angina
symptoms of angina pectoris
chest pain - heavy/tight/gripping - central/retrosternal
pain radiating to jaw and left arm
can be precipitated by cold
SOB
Sweatiness
3 main features
1 - constricting discomfort in the front of the chest, arms, neck, jaw
2 - provoked by physical exertion (after meals and in cold etc)
3 - relieved with rest or GTN spray.
signs on exam for angina pectoris
usually no signs though 4th heart sound maybe heard
should look for signs of anaemia, thyrotoxicosis, hyperlipidemia
treatment for STEMI
PCI or angioplasty
if unstable for PCI then fibrinolysis required (streptokinase)
beta blocker - atenolol 5mg
ACE-Inhibitor within 24 hrs of acute MI esp if LV dysfunction or HR
differential diagnosis for angina pectoris
- unstable angina (pain at rest and on exertion)
- prinzmetal’s angina - pain on rest and no RF for atherosclerosis
- MI - sudden, severe, crushing chest pain, do not stop after 15 mins
- Cardiac Syndrome X - pain unpredictable, occurs at rest and for loner period of time
- decubitus angina - pain occurs when lying down, severe coronary artery disease
- acute pericarditis - burning/sharp pain, radiates to neck/shoulders, worse on coughing/breathing/lying down
- GORD
- aortic dissection
- gallstones/acute cholecystitis
- anxiety
investigation for angina pectoris
largely clinical
resting ECG - usually normal between attack, during attack, ST depression, and T wave inversion maybe present, Q wave indicate old MI
exercise ECG - confirm diagnosis, gives indication for severity of CAD
cardiac scintigraphy - myocardial perfusion scans at rest and exercise
echocardiography - good for diagnosing CAD and exclude other causes
CV MRI
Coronary angiography
