Heart Failure - Atherton and Galbraith lectures

Question 1

what are the clinical mechanisms leading to heart failure?

Answer 1

1. myocardial failure - systolic (abnormal emptying) - diastolic (abnormal filling) 2. valvular heart disease 3. pericardial disease 4. shunts

Question 2

Label A -> D

Answer 2

A: end-diastole

b: AV opens (once the LV pressure is greater than the aortic pressure)

C: end systole

D; mv opens (once the LV pressure is lower than the LA pressure)

from this image: ~ 120 mL is the end diastolic volume (point A and B)

50mL is the end systolic volume (point C and D)

A is EDP

C is the end systole pressure point.

B is the diastolic blood pressure

The very top of the curve is the maximum LV pressure, and provided there is no LVOT obstruction, then this is also the systolic blood pressure

Question 3

what happens to end systolic pressure if given a positive iontrope?

Answer 3

see image

Question 4

where does angiotensin II act?

Answer 4

it causes arteriolar vasoconstriction, particularly the renal efferent

there is also NA and aldosterone release in response to its action

Question 5

when some one has concentric hypertrophy of the ventricular wall, in what manner do the sarcomeres increase?

what about eccentric hypertrophy?

Answer 5

see image

Question 6

what is the role of digoxin in patients with heart failure?

Answer 6

it can be useful to improve symptoms, control heart rate in AF and has been shown to improve LV function

HOWEVER

DOES NOT IMPROVE PROGNOSIS

Question 7

WHAT IS THE ROLE OF POSITIVE INOTROPIC AGENTS?

e.g. dopamine, milranone

Answer 7

they short term benefit, improve symptoms

however, they are catecholamine stimulating drugs and therefore lead to damage of the heart.

they have been shown time and time again to make prognosis worse

Question 8

are hydralazine and nitrates used in heart failure?

are they prognostic or symptomatic treatments?

Answer 8

these drugs have been shown to improve prognosis. they are good options for pregnant women with heart failure

Question 9

what is the most likely reason for increasing prevalence of HF in the community?

Answer 9

this used to be “improved survival of patients with coronary heart disease”

HOWEVER

this is now changed to ageing of the population.

Question 10

what happens in constrictive pericarditis to the haemodynamics?

Answer 10

the left and right ventricular diastolic pressures equalise.

This is because the heart is in a rigid box, once a chamber fills, they all have to be equal, because they are in a rigid container.

Question 11

what is the predominant cause of hyponatraemia in heart failure?

Answer 11

it is from increased ADH action