Theme 3 - IHD and ACS Flashcards
what is the main characterisation of coronary heart disease?
build up of cholesterol deposits in coronary arteries
what is cerebrovascular disease?
build up of cholesterol in the arteries supplying the brain
what is peripheral vascular disease?
furring of the arteries in the lower limbs
what is the main characterisation of IHD?
atherosclerotic progression in the intimial layer of one or more blood vessels
what does plaque progression in blood vessels cause?
myocardial blood flow is obstructed and reduced oxygen availability therefore ischaemia
what are the four main clinical manifestations of IHD?
asymptomatic (silent iscahemia), stable angina, acute coronary syndrome (unstable angina, STEMI, NSTEMI), long term (heart failure and death)
what is the pathology of stable angina?
fixed atheroma in more than one coronary artery
what is the pathology of unstable stable angina?
ischaemia due to dynamic obstruction eg plaque rupture
what is the pathology of an MI?
myocardial necrosis dude to acute occulusion of a CA due to plaque rupture or thrombosis
what is the pathology of heart failure?
myocardial dysfunction due to infarction or ischaemia - scarring affects electrics
what is the pathology of sudden cardiac death?
ventricular arrhythmia, asystole or massive MI
what is the cause of ischaemia?
obstruction leading to an imbalance between myocardial oxygen supply and demand - circulation cant meet needs
what are the three main classifications of chest pain?
typical angina, atypical angina and non anginal chest pain
what are the three criteria must chest pain meet to be classified as typical angina?
1) sub or retrosternal chest discomfort
2) provoked by exertion or stress
3) relieved by rest or nitrates (in mins)
how is atypical angina characterised?
must meet 2 of
1) sub or retrosternal chest discomfort
2) provoked by exertion or stress
3) relieved by rest or nitrates (in mins)
how is non anginal chest pain characterised?
meets one or none of
1) sub or retrosternal chest discomfort
2) provoked by exertion or stress
3) relieved by rest or nitrates (in mins)
what is first line treatment for stable angina?
short acting nitrates plus beta blockers or calcium blockers (and focus on lifestyle management)
what is second line treatment for stable angina?
ivabradine (inhibits funny current), long acting nitrates, nicorandil or invasive techniques such as PCI stenting
what conditions are acute coronary syndromes?
unstable angina, STEMI and NSTEMI
what will be detected in a blood test after a patient has had an acute MI?
raised troponin levels
would a patient with unstable angina have raised troponin levels?
no
from what time can troponin be detected in the blood after an MI and for how long?
can be detected within 3 hours and stay there for 2 weeks
what is ST elevation a marker of?
complete coronary occlusion
what are four factors the can be associated with an NSTEMI?
ST depression, variable T wave, normal ECG, increased troponin level
what type of occlusion is associated with an NSTEMI?
incomplete occlusion
where does thrombosis develop and what is the development of these associated with?
develops at the site of disruption of an atherosclerotic plaque within the wall of a coronary artery
- associated with acute coronary syndromes
what is the sequence of the development of a plaque?
normal –> fatty streak –> fibrous plaque –> atherosclerotic plaque
what causes a thrombosis when a plaque ruptures?
adherence, activation and aggregation of platelets
what molecule released from plats also aids thrombus formation
thromboxane A2
what are the main presenting symptoms of ACS (MI and UA)?
- discomfort and pain in the centre of the chest - recurring or lasts for few mins
- radiating pain to left arm, jaw and back
- occurs at rest or exertion
- no relieved immediately by sublingual nitrates
what do elderly/diabetic patients with an ACS present with?
breathlessness, nausea and vomiting and sweatiness/clamminess
what emergency investigation should be carried out if a patient is having a STEMI?
emergency angiogram to find where the occlusion is
what are the four main therapeutic goals in ACS?
1) restore coronary artery patency in a STEMI
2) limit myocardial necrosis
3) control symptoms
4) then medical management - anti plaits, anti iscahemic, and secondary prevention therapy
what is involved in primary medical management of ACS?
- anti plat agents eg aspirin, clopidogrel, prasugrel, ticagrelor
- anti ischaemics - nitrates (SL or infusion)
what secondary prevention therapy can be given to patients being discharged after ACS?
- statins to lower cholesterol
- ACE inhibitors/beta blockers - decreasing BP will help remodelling
- smoking cessation/lifestyle modification
what is the most critical time in a STEMI?
in the very early phase when patient is liable to cardiac arrest
how can a coronary artery be re-opened in a STEMI?
with a primary angioplasty - artery is mechanically opened using a balloon/stent to restore blood flow
what may be used in a STEMI if there is no access to primary angioplasty?
thombolytics - clot busting drugs
what four things can characterise unstable angina?
angina at res, new onset (asymptomatic to symptoms In less than 2 months), recent acceleration of symptoms, normal cardiac biomarkers eg troponin
what other conditions may troponin be elevated in?
pneumonia, PE, pericarditis, sepsis
how is unstable angina/NSTEMI managed?
analgesia, anti plats/ischaemics, statins, angiogram wifin 72 hours to see if they need a stent
what does a coronary bypass involve and who may this be given to?
- anatomoses from the saphenous vein or internal mammary artery to the occluded artery
- may be given to stable patients with no ST elevation
