265 - cardiac

Question 1

what is CHD also known as?

Answer 1

coronary heart disease aka IHD (ischaemic heart disease) or coronary artery disease (CAD)

Question 2

what are the two major clinical forms of CHD?

Answer 2

AMI and angina

Question 3

what is the main cause of CHD?

Answer 3

atherosclerosis

Question 4

describe blood supply to the heart

Answer 4

left and right coronary arteries supply each side

left branches into the circumflex artery and the left anterior descending (LAD) artery

Question 5

difference between ischaemia and hypoxia?

Answer 5

ischaemia - lack of blood flow

hypoxia - lack of oxygen

Question 6

pathogenesis of atherosclerosis

Answer 6

damage to endothelium of blood vessels (chronic) →
development of a fatty streak →
fibrous plaque forms resulting in narrowing of lumen

Question 7

risk factors for chronic endothelial injury which can lead to athersclerosis?

Answer 7

hypertension
smoking
hyperlipidaemia
diabetes
infections
toxins

Question 8

what is acute coronary syndrome?

Answer 8

unstable angina and MI - the more serious manifestations of CAD

Question 9

most common type of cardiovascular disease?

Answer 9

CHD (CAD)

Question 10

what type of disease is coronary artery disease?

Answer 10

Coronary artery disease is a type of blood vessel disorder that is included in the general category of atherosclerosis

Question 11

mortality rate for MI?

Answer 11

decreasing, but remains the leading cause of death from all cardiovascular diseases and death in general

Question 12

most common cause of ischaemia?

Answer 12

atherosclerosis

Question 13

difference between atherosclerosis and arteriosclerosis?

Answer 13

Arteriosclerosis is the stiffening or hardening of the artery walls.

Atherosclerosis is the narrowing of the artery because of plaque build-up.

Atherosclerosis is a specific type of arteriosclerosis.

Question 14

define myocardial ischaemia?

Answer 14

imbalance between oxygen supply and demand to the heart tissue

narrowing of a major coronary artery by > 50% → ischaemia, especially during
exercise

Question 15

how quickly do cardiac cells form lactic acid after an occulsion? for how long are cardiac cells viable after occlusion?

Answer 15

after 10 seconds of anaerobic respiration

cells are viable for 20 mins, then infarct will occur

Question 16

signs and symptoms of MI?

Answer 16

severe pain
chest discomfort - heaviness, pressure
pain may radiate to left arm, neck
pallor and diaphoresis
dyspnoea may occur

Question 17

most common drug used to treat angina?

Answer 17

nitrates - anginine, GTN

Question 18

aim of anti-anginal drugs?

Answer 18

reduction of cardiac workload

Question 19

adverse effects of nitrates?

Answer 19

hypotension
fainting
flushing
headache

Question 20

MOA of nitrates?

Answer 20

metabolised to nitric oxide in vessel walls → causes vasodilation of blood vessels → decreases preload and afterload → decreases SV →decreases cardiac output →decreases O2 demands → reduced cardiac workload

Question 21

nitrates: routes of administration?

Answer 21

sublingual, IV, nasal spray

Question 22

management options for AMI?

Answer 22

angioplasty, anticoagulants

Question 23

what is an AMI?

Answer 23

irreversible myocardial cell death (necrosis) as a result of sustained ischaemia >20 minutes

Question 24

most common cause of AMI?

Answer 24

secondary to thrombus in 80%-90% of cases

Question 25

how long does the necrosis of the entire thickness of the myocardium take?

Answer 25

4-6 hours

Question 26

what is AF?

Answer 26

disorganization of atrial electrical activity due to multiple ectopic foci where the P waves are replaced by chaotic, fibrillatory waves