Heart failure Flashcards
Define what is meant by heart failure
This is a state where cardiac output is inadequate for the body tissue requirements
What is the 2 main underlying pathophysiological causes of heart failure ?
Heart failure results from structural or functional impairment of ventricular filling or ejection of blood
Impairment of left ventricular filling:
- In diastole, the left ventricle (LV) walls relax allowing for filling of the LV cavity
- Without proper LV relaxation, the volume of blood filling the cavity is reduced, thus reducing the stroke volume, the volume of blood ejected with each contraction
Impaired ejection of blood:
- Due to LV wall damage, the LV may have reduced ability to pump or eject the blood
What are the causes of heart failure ?
- Coronary Heart Disease (± MI)
- Hypertension
- Diabetes
- Dilated Cardiomyopathy
- Valve disease
- Tachycardic arrhythmias (poorly controlled AF)
What are the 2 main types of heart failure presentations ?
Acute & chronic heart failure
Define what is meant by acute heart failure
- Acute heart failure (AHF) is life-threatening emergency. AHF is a term used to describe the sudden onset or worsening of the symptoms of heart failure.
- Thus it may present with or without a background history of pre-existing heart failure. AHF without a past history of heart failure is called de-novo AHF.
Define what is meant by chronic heart failure
If the symptoms have been going on for some time, it is called chronic heart failure.
What are the classical symptoms of heart failure?
SOB
Difficulty breathing at night when recumbent:
- Orthopnoea
- Paroxysmal nocturnal dyspnoea
Reduced exercise tolerance
Fatigue
Tiredness
What are the classical signs of heart failure?
Neck exam:
- Elevated JVP
Auscultation of the lungs:
- Rales or crackles (bibasal)
Auscultation of the heart:
- Third or fourth heart sound (S3 or S4) sometimes called a gallop rhythm
- Murmur
Oedema in dependent areas:
- Sacrum
- Feet/ankles/lower legs
What are the 4 grades of the The New York Heart Association (NYHA) functional classification of heart failure?
- I = Heart disease present, but no physical limitations or dysponea from ordinary activity
- II = Comfortable at rest, slight limitations of physical activity & dysponea on ordinary activities
- III = Comfortable at rest, but marked limitations of physical activity & less than ordinary activities causes dysponea
- IV = dysponea at rest, all activities cause discomfort
What should you initially do in all patients with suspected heart failure?
- Thorough history & exammination
- ECG, CXR, blood tests (including FBC, TFT’s, LFT’s, lipid profile, HbA1c, Troponin), Urinalysis, Peak flow or spirometry and a measurement of serum natriuretic peptides (NT-proBNP or BNP)
A level of NT-proBNP or BNP makes a diagnosis of heart failure likely ?
NT-proBNP >400
BNP ≥100
A NT-proBNP level of what rules out heart failure?
- NT-proBNP < 300ng/L
- BNP < 100
If someone following initial investigations for heart failure has a level of NT-proBNP > 400 what is done to diagnose heart failure?
Transthroacic echocardiogram (2-D echocardiogram with Doppler)
What causes of heart failure can an ECG help indentify ?
- Arrhythmias (irregular heart rhythms)
- Past myocardial infarction (MI)
- Left ventricular hypertrophy
What signs on a CXR are suggestive of heart failure and how do you remember it ?
Remeber the signs by ABCDE