heart failure

Question 1

what is class 1 heart failure?

Answer 1

no symptoms during normal physical activity

Question 2

what is class 2 heart failure?

Answer 2

comfortable at rest but symptoms during physical activity

Question 3

what is class 3 heart failure?

Answer 3

comfortable at rest but symptoms during activity

Question 4

what is class 4 heart failure?

Answer 4

unable to carry out any physical activity and may even have symptoms when resting

Question 5

give 5 clinical features of heart failure?

Answer 5

reduced ejection fraction
oedema
cold peripherals
reduced urine flow
hypotension

Question 6

explain how reduced cardiac output (as a result of heart failure) leads to oedema?

Answer 6

reduced cardiac output leads to reduced renal flow, which releases renin and forms angiotensin 2, aldosterone is released and Na+ and water are retained

Question 7

what is ejection fraction?

Answer 7

the percentage of blood pumped out by the left ventricle at each contraction

Question 8

what drug treatment is offered when anyone is diagnosed with heart failure?

Answer 8

a diuretic

Question 9

what are the two steps of treatment for someone diagnosed with heart failure with preserved ejection fraction?

Answer 9

• manage their comorbidities e.g high blood pressure / high cholesterol
• offer them an exercise based cardiac rehabilitation program

Question 10

what are the three steps of treatment for someone with heart failure with reduced ejection fraction?

Answer 10

• offer an ACE inhibitor and a beta blocker (or alternatives if not tolerated)
• if this does not work offer a MRA (aldosterone antagonist)
• if symptoms persist, offer one of the following:
  digoxin
  livabradine
  hydrazine with nitrate

Question 11

what do loop diuretics do?

Answer 11

reduce electrolyte reabsorption in the ascending loop of henle, promoting urinary excretion of Na+, K+ etc

Question 12

how do MRA’s prevent fluid retention and what electrolyte levels need monitoring on this drug?

Answer 12

block the aldosterone induced production of sodium transport proteins in the distal convoluted tubule causing the loss of water and sodium in urine. potassium (K+) needs monitoring

Question 13

which enzymes are needed in the formation of mevalonic acid in cholesterol biosynthesis?

Answer 13

thiolase
HMG-CoA synthase
HMG-CoA reductase

Question 14

which 2 chemical structures of statins allows them to mimic the natural substrate and bind to HMG-CoA?

Answer 14

the decalin ring and polar head