Cardiovascular Medicine

Question 1

what are the functions of the CV system

Answer 1

supply organs with O2, glucose, nutrients etc - hormonal messaging
removal of waste products
respond to changes in demand such as exercise or cold
stop bleeding, repair damage
begin fight against infection

Question 2

what are the risk factors of heart disease

Answer 2

dyslipidaemia 
smoking
diabetes 
hypertension 
male sex 
increasing age 
family history

Question 3

atherosclerosis starts with endothelial damage - what is this caused by

Answer 3

expression of inflammatory molecules - ICAM, selections etc
release of inflammatory cytokines
increased permeability to inflammatory cells, lipids

Question 4

following endothelial damage what happens next in the formation of atherosclerosis

Answer 4

monocytes differentiate to macrophages
t lymphocyte action
accumulate lipid (foam cells)
these foam cells undergo apoptosis
results in lipid pools in sub endothelial space
produces a plaque
fibrous collagen cap formation including cells

Question 5

what makes the plaque formation complex

Answer 5

mix of: 
lipid cholesterol 
cells and cell debris (macrophages, T Cells, smooth muscle cells) 
colagen, elastin, MPPS
calcification 
highly thrombogenic

Question 6

what is atherothrombosis

Answer 6

plaque rupture
thrombogenic core exposed to blood
clotting cascade activated which recruits platelets
thrombus forms
vessel occlusion which leads to infarction, ischeamia

Question 7

what is an embolism

Answer 7

clot embolisation
distal vessel occlusion eg CVA
arrythomgenic potential

Question 8

where are some common areas of atherosclerotic disease

Answer 8

brain - TIA, carotid disease, stroke 
heart - angina, MI, arrhythmia, HF 
Kidneys - renal failure 
aortic aneurysm 
impotence 
peripheral vascular disease - intermittent claudication, gangrene

Question 9

what are the symptoms and causes of angina

Answer 9

chest pain due to myocardial ischaemia usually due to flow limiting atherosclerosis
also caused by anaemia
pain in arms and jaw with crushing chest pain

Question 10

what is the clinical aspect of angina in terms of symptoms

Answer 10

constricting discomfort in the front of chest, neck, shoulders, jaw
precipitated by physical exertion
relieved by rest or GTN (glyceryl trinitrate - vasodilator) within about 5 mins

Question 11

what symptoms show that it is unlikely to be angina

Answer 11

chest pain which is 
continuous or very prolonged 
unrelated to activity 
brought on by breathing in 
associated with symptoms such as dizziness, palpitations, tingling

Question 12

what phases of the heart happen during diastole

Answer 12

isovolumic ventricular relation
rapid ventricular filling
slow ventricular filling
atrial contraction

Question 13

what phases of the cardiac cycle occur during diastole

Answer 13

isovolumic ventricular contraction

ejection

Question 14

what occurs during stage one of the mechanical cardiac cycle

Answer 14

late diastole - both sets of chambers are relaxed and ventricles fill passively

Question 15

what is stage 2 of the mechanical heart cycle

Answer 15

atrial systole

atrial contraction forces a small amount of additional blood into ventricles

Question 16

what is stage 3 of the mechanical cardiac cycle

Answer 16

isovolumic ventricular contraction - first phase of ventricular contraction pushes AV valves closed but not enough pressure to open semi lunar valves

Question 17

what is the 4th stage of the mechanical cardiac cycle

Answer 17

ventricular ejection - as ventricular pressure rises and exceeds pressure in the arteries the semilunar valves open and blood is ejected

Question 18

what is the 5th and final stage of the mechanical cardiac cycle

Answer 18

isolvolumic ventricular relaxation - ventricles relax - closes semi lunar valves and blood flows into atria

Question 19

describe the electrical events of the cardiac cycle in terms of an ECG

Answer 19

start - p wave is atrial contraction
P-Q or P-R segment - conduction through Av node and AV bundle
movement down the bundle and branches of HIS cause the small downward deflection (Q) before the R peak - ventricles continue to contract after QRS - then T wave is ventricular repolarisation

Question 20

what is stroke volume

Answer 20

volume of blood ejected from the left ventricle with each cardiac cycle (resting 70 ml)

Question 21

what is cardiac output

Answer 21

volume of blood ejected from the left ventricles each minute (resting 5 L/min)