8 - Ischaemic Heart Disease Flashcards
If infarct patterns are present in leads I, V5, V6 and aVL, what area of the heart has the infarct occurred in and which artery supplies it?
Lateral heart damage
Supplied by left circumflex artery
If infarct patterns are present in leads II, III and aVF,what area of the heart has infarction occurred in and which artery supplies it?
Inferior heart damage
Supplied by right coronary artery
If infarct patterns are present in leads V1 and V2, what area of the heart has the infarction occurred in and which coronary artery supplies it?
Septal area of heart
Supplied by left anterior descending artery
If infarct patterns are present in leads V3 and V4, what area of the heart has the infarct occurred in and what artery supplies it?
Anterior heart damage
Supplied by right coronary artery
Define ischaemic heart disease
Chest pain secondary to pathology involving the heart that affects its blood supply
What are the modifiable risk factors for ischaemic heart disease?
Smoking Hypertension Diabetes Obesity Sedentary lifestyle Hypercholesterolaemia
What are the non modifiable risk factors for ischaemic heart disease?
Old age
Family history
Male
When does ischaemic heart disease occur?
When the metabolic demands of the cardiac muscle are greater than what can be delivered by the coronary arteries, e.g. When atherosclerosis reduces blood flow through the coronary arteries
What are acute coronary syndromes?
Acute myocardial ischaemia caused by atherosclerotic coronary artery disease on a spectrum of acute increasing occlusion
Name the acute coronary syndromes
Unstable angina
Myocardial infarction
NSTEMI
STEMI
Describe the pathology that leads to acute coronary syndromes
Atherosclerotic plaque forms
Atherosclerotic plaque ruptures
Platelets aggregate and form a thrombus that is partially occlusive, can progress to be fully occlusive
What is the different between cardiac tissue ischaemia and infarction?
Infarction - cardiac enzymes leak from necrosed muscle tissue
Ischaemia - no enzyme leakage
Describe the typical history for lung/heart pain
Visceral
Dull
Poorly localised pain
Worse with exertion
Describe the typical history of pleural/ pericardial sac pain
Somatic
Sharp
Localised pain
Worse with inspiration, coughing and positional movement
Describe the typical history of pericarditis, including ECG
Sharp Localised pain to front of chest Worse with inspiration, coughing and lying flat Pericardial rub heard on auscultation ECG - wide concave ST elevation
Describe the typical history for stable angina
Dull retrosternal pain, can radiate up to neck
Triggered by exertion
Relieved by rest
How is stable angina treated?
GTN spray under tongue during episodes Beta blockers ACE inhibitors Statins Calcium channel blocker Surgery - coronary artery bypass or angioplasty
What is the difference in histories between stable and unstable angina?
Unstable angina: Intense pain Longer lasting pain Pain occurs at rest ECG pattern shows NSTEMI pattern
Describe the typical history for a myocardial infarction
Dull retrosternal crushing pain
Pain radiates to left arm and left side of the jaw
No relieving factors
Sweating, pallor and nausea (Increased sympathetic output)
What tests would you carry out if you suspected an MI and what would they show if you are right?
Blood test for cardiac markers such as troponin c that indicate cardiac myocyte death
ECG - will show ST elevation and Q waves for a STEMI, ST depression or T wave inversion for NSTEMI
How would you treat a confirmed myocardial infarction?
Oxygen
Pain relief
GTN sublingually
Antiplatlets
What are the differences between a STEMI and an NSTEMI?
STEMI - caused by acute total occlusion of coronary artery
ECG shows ST elevation and q waves
NSTEMI - caused by acutely progressive tight stenosis of a coronary artery
How does blood flow into the coronary arteries?
When the heart is relaxed, back flow of blood flows into the aortic sinuses (behind aortic valve) into the coronary arteries
