Heart failure

Question 1

The most common cause of heart failure

Answer 1

MI

More people survive it now and consequently are living with heart failure

Question 2

Causes of heart failure aside from MI

Answer 2

Pressure overload - hypertension, aortic stenosis
Volume overload - valve regurgitation
Contractile dysfunction - ischemic heart disease, congenital cardiomyopathy, pregnancy, cardiomyopathies

Question 3

Symptoms of right-sided heart failure?

Answer 3

tiredness and weakness, urinating less, peripheral oedema (up to thighs, sacrum, abdominal wall), ascites, nausea, anorexia, facial engorgement, epistaxis

Question 4

The treatment for an MI

Answer 4

Percutaneous coronary intervention

Pass a wire through the clot and put a stent in to allow return of blood

Question 5

What heart failure does to the Starling curve

Answer 5

curve is shallower and doesn’t reach same peak

Question 6

Why do patients with HF have chronically high plasma catecholamines (adrenaline, NA)?

Answer 6

Baroreceptor response to a decrease in BP –> increase SNS activity to adrenal glands –> adrenaline (mainly) & NA act on B1 receptors in heart, supplementing SNS nerves

Question 7

Consequence of persistent adrenergic stimulation of the heart

Answer 7

Initially - good, increase inotropy and SV
later - contractile dysfunction in myocytes leads to ectopic activity and arrhythmia, internalisation of adrenoreceptors leads to exercise intolerance, also get pathological hypertrophy

Question 8

Why are baroreceptors stimulated in HF

Answer 8

Decreased ventricular function means decreased SV and CO so decreased ABP which is detected

Question 9

Baroreceptors detect decreased ABP –> less afferent activity to CNS –> CNS action on the kidney?

Answer 9

increases sympathetic activity to the kidneys (vasoconstriction of renal artery - lower GFR - more renin release)

Question 10

Renin effect on blood pressure

Answer 10

RENIN RAISES BP

Question 11

Why do patients with HF have chronically high angiotensin II

Answer 11

• Low ABP detected by baroreceptors –> CNS acts on kidneys
• Low ABP detected directly by the kidneys (macula densa, arterioles)

Result is to RAISE RENIN

Question 12

the initial consequence of increased blood volume in (early stage) heart disease

Answer 12

increased EDV allows SV to be maintained at rest along with increased contractility (ejection fraction maintained)

Question 13

the later consequence of increased blood volume in (late stage) heart disease

Answer 13

increased EDV goes beyond the plateau of the Starling curve and so SV can no longer be maintained (reduced ejection fraction)

Question 14

How does left sided HF cause pulmonary oedema

Answer 14

mis-match in LV and RV CO due to failing heart causes blood to accumulate in pulmonary circulation –>
Increased capillary hydrostatic pressure –> increased capillary filtration

Question 15

What classic symptom of HF is caused by pulmonary oedema

Answer 15

SOB

Question 16

How can left sided heart failure cause right sided heart failure

Answer 16

Left sided HF –> pulmonary oedema –> pulmonary vasoconstriction –> pulmonary hypertension –> right sided HF (pressure overload)

Question 17

What treatments can be given to reduce afterload on the heart

Answer 17

vasodilators - reduce TPR

Question 18

What treatments can be given to reduce cardiac work

Answer 18

beta blockers

Question 19

How does cardiac hypertrophy increase susceptibility to ischemia

Answer 19

Larger myocytes mean they become further and further away from the capillary blood source

Question 20

What treatments are given for pulmonary oedema (to decrease blood volume)

Answer 20

ACE
ARBS
loop diuretics

Question 21

what does cardiac hypertrophy increase risk of

Answer 21

arrhythmia

sudden cardiac death

Question 22

Where does blood get backed up to in right sided heart failure

Answer 22

systemic circulation

• hepatosplenomegaly, pitting oedema in legs

Question 23

Where does blood get backed up to in left sided heart failure

Answer 23

pulmonary circulation

- pulmonary oedema

Question 24

Symptoms of left-sided heart failure?

Answer 24

SOB/dyspnoea, poor exercise tolerance, orthopnoea, fatigue & weakness, urinating less, paroxysmal nocturnal dyspnoea (PND), nocturnal cough (& pink frothy sputum), wheeze (cardiac ‘asthma’), cold peripheries, weight loss

Question 25

The term ‘congestive heart failure’ (CHF) is reserved for patients with…

Answer 25

breathlessness and abnormal sodium and water retention resulting in oedema (BMJ)

Question 26

Define heart failure

Answer 26

the heart is unable to generate a cardiac output sufficient to meet the demands of the body without increasing diastolic pressure

Question 27

left ventricular failure and right ventricular failure can occur independently, or together in which case they are called

Answer 27

chronic congestive (heart) failure