Heart Failure Presentation and Investigation

heart failure defined as a clinical syndrome comprising of dyspnoea, fatigue or fluid retention due to cardiac dysfunction, either at rest or on exertion, with accompanying neurohormonal activation

relatively common, increasing, more common in elderly

biggest cost is in hospital stay

up to two weeks admission time

primarily admitted due to acute breathlessness, peripheral oedema

high re-admission rate, happen early in the first week

high morbidity and mortality

massively enlarged heart, congested lungs- easily diagnose heart failure

objective evidence of cardiac dysfunction mandatory

-echocardiography *main, radionuclide ventriculography, MRI, left ventriculography

potential screening tests - 12 lead ECG

-BNP, peptide rises when heart in stress or strain, if BNP is low heart failure unlikely, if BNP moderate or high heart failure more likely

looking for high sensitivity

sensitivity of 1 and specificity of 1 preferable

larger area under curve, more accurate the test is as a diagnostic test

BNP predicts mortality and morbidity

if sufficiently severe almost any structural cardiac abnormality will cause heart failure

take a detailed history to evaluate patients if they have Left ventricular systolic dysfunction, as they are many causes the detailed history should make more causes more likely than others

always ECG, sometimes CXR, ECHO

consider coronary angiography if chest pain, not really for those >70

LV ejection fraction is a continuous biological variable

–Disease / physiological changes can both decrease and increase the LVEF

–The LVEF may be lower than previous but not pathologically low

–Analagous to Haemoglobin / anaemia

•eg. fall in Hb from 17g/dL to 14.5g/dL

LV function assessment and LVEF

normal 55-70%

mild 40-55%

moderate 30-40%

severe <30%

Cardiac MRI has better image quality

more impaired left ventricular function, worse prognosis

grading the severity of HF:
-degree of LV impairment

-NYHA class i.e. severity of symptoms

-degree of elevation of BNP

heart failure does not equal reduced cardiac output (at rest)

angiotensin receptor and neprolysin inhibitor -pharmacological therapy, same sort of effect as ACE inhibitor

neprolysin blocks the breakdown of BNP