Ischemic heart disease Flashcards
What is cardiovascular disease?
A disease of the heart or circulatory system which comprises coronary heart disease, cerebrovascular disease and peripheral vascular disease
Which study determined the concept of risk factors in cardiovascular disease?
Framingham heart study
List the controllable risk factors of coronary heart disease
Cigarette Smoking Diabetes High blood pressure High cholesterol Obesity
List the non controllable risk factors of coronary heart disease
Age
Gender
Family history of premature coronary disease
Previous heart attack
What does atherosclerosis involve?
Development of a fatty streak
Lipid deposition
Intimal fibrosis
How does ischemic heart disease develop?
Atherosclerotic plaque build up within one or more coronary arteries, obstructing myocardial blood flow
What does the process of ischemic heart disease development cause?
This leads to an imbalance between myocardial oxygen supply and demand
Restricts normal increase in coronary blood flow in response to increase in myocardial oxygen demand
List the clinical manifestations of ischemic heart disease
Asymptomatic
Stable angina
Acute coronary syndromes - (Unstable angina, NSTEMI, STEMI)
Long-term - (Heart failure, Arrhythmias, Sudden death)
Define stable angina
Ischemia due to fixed atheromatous stenosis of 1 or more coronary arteries
Define unstable angina
Ischemia caused by dynamic obstruction of a coronary artery due to a plaque rupture with superimposed thrombosis and spasm
Angina at rest ( > 20mins)
New onset ( < 2 months) exertional angina (at least CCS III in severity)
Recent ( < 2months) acceleration of angina (increase in severity of at least one CCS class to at least III)
Normal cardiac biomarkers (troponin)
Define myocardial infarction
Myocardial necrosis caused by acute occlusion of a coronary artery due to a plaque rupture or thrombosis
Define heart failure
Myocardial dysfunction due to ischemia/infarction
Define arrythmia
Altered conduction due to ischemia or infarction
Define sudden death
Ventricular arrhythmia, asystole or massive myocardial infarction
State and define the classification of angina
Class I: Ordinary physical activity (such as walking and climbing stairs) does not cause angina
Class II: Angina causes slight limitation of ordinary physical activity
Class III: Angina causes marked limitation of ordinary physical activity
Class IV: Inability to perform any physical activity without angina
Define typical angina
Meets all 3 of the following characteristics:
Substernal chest discomfort of characteristic quality and duration
Provoked by exertion or emotional stress
Relieved by rest and nitrates within minutes
Define atypical angina
Where only 2 of the required characteristics to diagnose typical angina are met
Describe some ways of managing a patient with angina
Short acting nitrates Beta blockers PCI, Stenting or CABG Lifestyle management Control of risk factors Education
What does the definition of the type of MI depend on?
The findings on the ECG
Name the 2 different types of MI
STEMI
NSTEMI
In hospitals which type of MI has associated higher death rates?
STEMI
Which type of MI causes an increase in the chance of the patient dying in the long term?
NSTEMI
What is ACS characterised by?
The development of a thrombosis at the site of acute disruption of an atherosclerotic plaque within the wall of the coronary artery
What do acute coronary syndromes consist of?
Unstable angina and myocardial infarcts
Following plaque disruption, thrombus results from…
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 vasoconstriction
What does a STEMI look like on an ECG?
ST elevation
What is an ST elevation a sign of?
Complete coronary occlusion
What does a NSTEMI look like on an ECG?
ST depression or normal ECG
What does a NSTEMI ECG signify?
Incomplete occlusion
What are the classical symptoms at presentation of ACS?
Discomfort/pain in the centre of the chest that lasts for more than a few minutes or recurs
Discomfort/pain radiating to other areas, e.g. arms/jaw/back
Not relieved immediately with S/L GTN
What are the symptoms more commonly present with ACS in elderly or diabetic patients?
Elderly or diabetic patients often present with:
Breathlessness
Nausea or vomiting
Sweating and clamminess
Which immediate assessments do you do when investigating a suspected ACS?
Patient history ECG Physical examination Risk stratification Cardiac biomarkers (troponin)
What are the therapeutic goals in ACS?
Restore coronary artery patency (STEMI)
Limit myocardial necrosis (STEMI)
Control symptoms
State the medical management in ACS
Anti-platelet therapy
Anti-ischaemic therapy
Secondary prevention
Describe secondary prevention methods for ACS
Antiplatelet therapy Aspirin Ticagrelor /clopidogrel /prasugrel Statin ACE inhibitors Beta blockers Smoking cessation Lifestyle modification
State the rapid treatment given in STEMI
Morphine and/or nitrates for pain relief
Antiplatelet agents (aspirin + ticagrelor*)
*Clopidogrel in high risk bleeding populations
AND
‘Primary’ angioplasty (balloons, stents): artery is mechanically reopened, restoring blood flow
“Clot-busting” drug (thrombolysis): pharmacologically break up clots, restoring blood flow when access to angioplasty delayed/unavailable
Define NSTEMI
Defined as the absence of persistent ST elevation (<20 minutes) on ECG, but with angina symptoms and elevated cardiac biomarkers
Who are the high risk patients?
Elevated troponin levels Renal impairment Recurrent chest pain Dynamic ST depression or T wave changes on ECG Haemodynamic instability Major arrhythmias Heart failure Elderly
Describe the management of UA/NSTEMI
Analgesia Antiplatelet therapy Anti-ischaemic therapy Statins Early coronary angiography with a view to revascularisation (stenting or CABG)
