2.01 - Heart

Question 1

What is the difference between STEMI, NSTEMI, and UA

Answer 1

STEMI -
ST elevation
New onset LBBB
Raised troponin

NSTEMI -
No ST elevation or LBBB
Raised troponin

UA -
No ST elevation or LBBB, normal troponin

Question 2

What is the most common cause of ACS

Answer 2

Artery narrowing or blockage secondary to IHD or atherosclerosis

Question 3

What are the causes of coronary artery occlusion

Answer 3

Vasculits (Kawasaki disease)
Coronary vasospasm (cocaine)
Coronary dissection

Question 4

What are some causes of changes of oxygen demand leading to ACS

Answer 4

Anaemia
Hyperthyroidism
Severe sepsis

Question 5

What are the modifiable risk factors for ACS

Answer 5

High cholesterol
HTN
Smoking
Diabetes
Obesity

Question 6

What are the non-modifiable risk factors for ACS

Answer 6

Agę
Family history
Male sex
Premature menopause

Question 7

what is the frank starling law

Answer 7

the ability of the heart to respond to increased venous return by increasing stroke volume

Question 8

how does the frank starling law work normally

Answer 8

increased venous pressure ->
raised EDV ->
increased preload (due to stretch) ->
more forceful contraction ->
increase in stroke volume

Question 9

how does heart failure break down the frank starling law

Answer 9

over stretching of cardiomyocytes -> impaired contractlity -> stroke volume cannot increase to match EDV
-> oedema in lungs and ankles

Question 10

what are the vascular causes of heart failure

Answer 10

ischaemic heart disease
hypertension

Question 11

what are the muscular causes of heart failure (3)

Answer 11

dilated cardiomyopathy
hypertrophic cardiomyopathy
congenital heart disease

Question 12

what are the valvular causes of heart failure (2)

Answer 12

stenosic valves
regurgitant valves

Question 13

what is an electrical cause of heart failure

Answer 13

arrhythmia

Question 14

what are the causes of high output heart failure (SALT)

Answer 14

Septicaemia
Anaemia
Liver failure
Thyrotoxicosis

Question 15

what compensatory mechanisms are involved in the pathophysiology of heart failure (4)

Answer 15

increasing preload
increasing heart rate
RAAS activation
SNS activation

Question 16

how does increasing preload contribute to heart failure

Answer 16

increase EDV to compensate for reduced ejection fraction -> maintain cardiac output
large increase in EDV can lead to pulmonary oedema, ascites, peripheral oedema

Question 17

how does increasing heart rate contribute to pathogenesis of heart failure

Answer 17

cardiac output = stroke vol * heart rate
unable to increase stroke vol so increase heart rate instead
sustained tachycardia leads to cardiomyocyte death and remodelling -> cardiomegaly

Question 18

how does RAAS activation contribute to pathogenesis of heart failure

Answer 18

renal hypoperfusion due to reduced CO -> RAAS
-> vasoconstriction and water retention
-> increased mean arterial pressure (BP)
-> oedema

Question 19

How does SNS activation contribute to pathogenesis of heart failure

Answer 19

increases myocardial contractility and heart rate
can trigger cardiomyocyte death when chronicall activated
causes a positive feedback loop and increases RAAS activation

Question 20

what are the clinical features of left sided heart failure (7)

Answer 20

paroxysmal nocturnal dyspnoea
orthopnoea
cyanosis
fatigue
SOB on exertion
tachycardia
Sx of pulmonary congestion

Question 21

what are the clinical features of right sided heart failure (7)

Answer 21

raised JVP
fatigue
peripheral oedema
ascites
anorexia, nausea, vomiting
weight gain
Hx of chronic pulmonary problems

Question 22

What are the diagnostic investigations for heart failure

Answer 22

B Natiuretic Peptide (BNP)
Transthoracic Echocardiography (TTE)

Question 23

what (other than heart failure) can cause a raised BNP

Answer 23

sepsis
diabetes
old age
hypoxia
CKD
liver cirrhosis

Question 24

what are the three positive (yes heart failure) results of a TTE

Answer 24

HFrEF - LVEF <40%
HFmrEF - LVEF 40-49%
HFpEF - LVEF >50%

Question 25

what are the requirements for each class of heart failure (new york classification)

Answer 25

1) no limitation to activity, no symptoms 2) slight limitation, symptomatic on exertion 3) marked limitation, symptomatic on light activity 4) physical activity impossible without discomfort, symptomatic at rest

Question 26

what further blood tests (other than BNP) are done when investigating heart failure

Answer 26

FBC - anaemia, infection U&E - renal failure as cause of oedema LFT - liver failure as cause of oedema Cholesterol and HbA1c - risk stratification TFT - exclude thyroid disease

Question 27

what imaging (other than TTE) is done to investigate heart failure

Answer 27

chest x ray cardiac mri

Question 28

what can be seen on a chest x ray of a heart failure patient (5)

Answer 28

cardiomegaly alveolar oedema kerley B lines pleural effusion upper love diversion

Question 29

what is cardiac mri used for when investigating heart failure

Answer 29

follow up if TTE was non diagnostic determine aetiology of heart failure

Question 30

what is the conservative management of heart failure

Answer 30

lifestyle modification patient education annual flu vax smoking cessation alcohol support travel and driving advice

Question 31

what is the medical management in HFrEF and HFmrEF

Answer 31

ACE inhibitors Beta blockers Mineralocorticoid Receptor Antagonists (MRAs) Loop diuretic

Question 32

What is the medical management in HFpEF

Answer 32

loop diuretic (furosemide) if symptomatic of fluid overload specialist referral comorbidity management