17 - Heart Failure Investigations Flashcards
What are the different classifications of heart failure using the NYHA system?
Outline the aetiology of heart failure
- Ischaemic Heart Disease
- Hypertension
- Dilated/hypertrophic Cardiomyopathy
- Valvular/Congenital Heart Disease
- Pericardial disease
- Arrhythmias
Explain why beta blockers are beneficial following myocardial infarction?
- MI causes increased sympathetic activity
- β-blockers reduce O2 demand, hence reducing myocardial ischaemia
Identify 4 features of heart failure
- Reduced force of contraction or reduced filling
- Reduced cardiac output
- Reduced tissue perfusion
- Oedema
What drugs in general are used for heart failure?
Anticoagulants
What is furosemide?
- Diuretic that can lessen symptoms such as shortness of breath and swelling in your arms, legs, and abdomen by reducing excess fluid in the blood
- Immediate venodilator, 30 min diuretic
- Higher doses needed in renal failure as poorer kidney perfusion
Why would you give IV nitrates to someone with heart failure?
Forms nitrous oxide causing vasodilation decreasing pre and after loads
What might you see on the chest x-ray of someone with heart failure?
- Cardiomegaly
- Fluid in the fissure
- Pleural effusions
- Pulmonary oedema
What investigations would you carry out to diagnose heart failure and the cause of it?
- CXR
- Transthoracic echocardiogram
- ECG
- Blood tests (FBC and BNP/NTpro-BNP)
- Possible coronary angiography for MRI for ischaemia
What blood tests can be carried out to investigate heart failure?
How can BNP be used to diagnose heart failure?
- Hormone released in reponse to atria/ventricle stretch due to fluid overloads
- Normal range varies with age and gender
- Atrial fibrillation can triple BNP
- Normal BNP can pretty much rule out heart failure
Why are beta blockers used for heart failure and why do they need to be used with caution?
- Negative inotrope so decrease workload of the heart
- Body could be depending on the tachycardia to supply the metabolic demands of the body so titrate slowly
What are the bad effects of the sympathetic nervous system being activated in heart failure?
- beta receptors are down-regulated/uncoupled so when needed not available
- Noradrenaline can induce cardiac hypertrophy/myocyte apoptosis and can upregulate RAAS
What changes does the SNS make to the CVS when activated in heart failure?
- Increase contractility
- Vasoconstriction
- Tachycardia
ALL TO INCREASE THE CO
What drugs can you use to combat the RAAS system?
- ACE inhibitors: prevent productuon of angiotensin II which is a vasoconstrictor and produces aldosterone so inhibitor stops this too.
- Angiotensin II receptor blocker
Although an angiotensin II receptor blocker may be being used, some aldosterone may still be produced increasing B.P. What drug can be used to combat this?
- Spironolactone
- Aldosterone receptor antagonist
Apart from drug treatment, what can be used to treat end stages of heart failure?
Outline the different stages of treating HFrEF.
To treat HFpEF best to treat the underlying cause
For the different types of heart failure outline the best treatment options:
- Left ventricular systolic dysfunction
- HFpEF
- Valvular heart failure
- Right ventricular failure
Do you think Arthur’s lungs are easy to inflate?
Following the previous case study of Arthur, why is his sputum creamy?
Also, which side of the heart has failed?
- Right sided heart failure secondary to lung disease (cor pulmonale)
- Can occur as a consequence of lung disease which elevates pulmonary resistance and therefore pressure in the pulmonary artery
How can you treat someone with cor pulmonale to help their heart failure?
Treat the underlying lung condition
