ischaemic heart disease Flashcards
name 3 types of cardiovascular disease?
- coronary heart disease
- cerebrovascular disease
- peripheral vascular disease
what are the risk factors for CVD? 8
- smoking
- diabetes
- high blood pressure
- high cholesterol
- obesity
- age
- family history of premature coronary disease
- previous heart attack
what are the clinical manifestations of coronary heart disease? 2
- atherosclerosis
- development of fatty streak, lipid deposition, intimal fibrosis
what is ischemic heart disease and myocardial ischaemia? 3
- IDH occurs due to atherosclerotic plaque build up within one or more coronary arteries , thereby obstructing myocardial blood flow
- this leads to an imbalance between myocardial oxygen supply and demand
- there is a restriction in the normal increase in coronary blood flow which should occur in response to an increase in myocardial oxygen demand
what are the clinical manifestations of IHD?
- asymptomatic
- stable angina
- acute coronary syndromes: unstable angina, NSTEMI (non-ST elevation myocardial infarction), STEMI
- long term: heart failure, arrhythmias, sudden death
what is the pathology of stable angina?
- ischaemia due to fixed atheromatous stenosis of one or more coronary arteries
what is the pathology of unstable angina?
ischaemia caused by dynamic obstruction of a coronary artery due to plaque rupture with superimposed thrombosis and spasm
what is the pathology of myocardial infarction?
myocardial necrosis caused by acute occlusion of a coronary artery due to plaque rupture and thrombosis
what is the pathology of arrhythmia?
altered conduction due to ischaemia or infarction
what is the pathology of sudden death
ventricular arrhythmia, asystole or massive MI
what are the characteristics of typical stable angina? 3
- substernal chest discomfort of characteristic quality and duration
- provoked by exertion or emotional stress
- relieved by rest of nitrates and minutes
- atypical angina=meets two of these characteristics
- non anginal chest pain= lacks or meets only one
how are patients with stable angina managed? 4
- regular medical therapy
- short acting nitrates +beta blockers or a calcium channel blocker= first line treatment
- second line treatment=long acting nitrates and more options
- if these don’t work we consider an angiography-putting people on statins
describe acute coronary syndromes? 5
- includes unstable angina and acute myocardial infarction
- in an acute MI, STEMIs and NSTEMIs are differentiated by the specific pattern of abnormality on the ECG
- all patients who have had an acute MI have a rise in the cardiac enzyme known as troponin which is measured on a blood test
- troponin is released into the bloodstream following injury to the heart muscle
- troponin levels are elevated in acute MI but not in unstable angina
describe the pathology of STEMI and NSTEMI? 2
- in general terms, ST elevation on an ECG is a marker of a complete coronary occlusion
- incomplete occlusion is associated with ST depression, variable T wave abnormalities or with a normal ECG
describe the pathological progression to atherothrombosis?
-ACS is characterised by the development of a thrombosis at the site of an acute disruption of an atherosclerotic plaque within the wall of the coronary artery
following plaque disruption, what does a thrombu result from? 3
- adherence, activation and aggregation of platelets
- thrombin and fibrin production via the coagulation cascade (and thrombin release from platelets)
- vasoactive molecules released from platelets which cause constriction
what are the classical ACS symptoms at presentation? 4
- discomfort/pain in the centre of chest that lasts for more than a few minutes or recurs
- discomfort/pain radiating to the other areas (left arm/jaw/back)
- can occur at rest and/or with exertion
- not relieved immediately with sublingual GTN
what do elderly or diabetic patients with ACS present with? 3
- breathlessness
- nausea/ vomitting
- sweating or clamminess
what is the immediate assessment of patients with suspected ACS? 5
- patient history
- ECG
- physical examination
- risk stratification
- cardiac biomarkers
what are the therapeutic goals in ACS? 3
- restores coronary artery patency (STEMI)
- limit myocardial necrosis (STEMI)
- control symptoms
how is ACS medically managed? 3
- antiplatelet- aspirin, clopidogrel, prasugrel/ ticagrelor
- anti-ischemic therapy- nitrates
- secondary prevention therapy- statin, ACE inhibitors, beta blockers, smoking, lifestyle modification
what is important about STEMI treatment? 3
- timely diagnosis is key to successful management
- the most critical time is in the very early phase when the patient is liable to a cardiac arrest
- minimising delays to treatment are associated with improved clinical outcome
what is the treatment for STEMI? 4
- morphine/nitrates for relief
- antiplatelet
- AND emergency primary angioplasty (balloons and stents), artery is mechanically reopened, restoring blood flow
- clot busting drug
describe unstable angina? 4
- angina at rest (>20mins)
- new onset (<2 months) exertional angina
- recent (<2 months) acceleration or progression of angina symptoms
- normal cardiac biomarkers- normal troponin levels
how do we identify NSTEMI?
defined as the absence of ST elevation on ECG, but with angina symptoms and elevated troponin
what things other than MI can cause heart attacks? 6
- pneumonia
- pulmonary embolism
- pericarditis
- sepsis
- heart failure
- uncontrolled tachyarrhythmia
what suggests ACS patients are high risk? 7
- elevated troponin levels
- renal impairment
- recurrent chest pain
- dynamic ST depression
- major arrhythmias
- heart failure
- elderly
what is the management of NSTEMI? 5
- analgesia
- anti-platelet therapy
- anti-ischaemic therapy
- statins
- early coronary angiography to view revascularization