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
What information do you get on transthoracic echo about heart failure ?
- Chamber size
- Right and left ventricular function
- Regional wall motion abnormalities (evidence of MI)
- Evidence of impaired LV filling (i.e., stiffness of the walls), a feature of diastolic dysfunction
- Valvular heart disease
- Diseases of the pericardium
- Ejection fraction
What is the ejection fraction ?
- EF is the percentage of blood that is pumped out of the heart during each beat
- A normal EF is ≥50%
What is the important of ejection fraction when assesed on echo in relation to heart failure and what are the 2 categories of heart failure based on ejection fraction ?
- Heart failure with an EF ≤40% is known as heart failure with reduced ejection fraction (HFrEF)
- Heart failure in the setting of a normal EF is known as heart failure with preserved ejection fraction (HFpEF)
Ejection fraction is key in dictating the management of heart failure
What happens in heart failure with a preserved and a reduced ejection fraction ?
Define what is meant by heart failure with a preserved ejection fraction (HFpEF)
- The diagnosis of Heart failure with Preserved Ejection Fraction is based on the clinical finding of congestive heart failure with the echo findings of preserved left ventricular ejection fraction and the absence of valvular abnormalities.
- LEVF ≥ 50%
What is the generic lifestyle management of heart failure (both presrved and reduced EF)?
- Supervised personalised exercise-based rehabilitation programme
- Avoid salt (<6g/day) & restrict water (1.5-2L)
What vaccinations should be given to all patients with heart failure ?
- A one off pnuemoccocal & annual influence
- Pnuemoccocal given every 5 years if asplenia, splenic dysfunction or CKD
If any patient with heart failure develops signs/symptoms of fluid overload or congestion what should be given ?
Diuretics - typically a loop diuretic e.g. furosemide but sometimes a thiazide duiretic will suffice if fluid retention is very mild
If a person with heart failure develops iron def. anaemia with a Hb between 9.5-13.5 what should they be given ?
IV iron (ferric carboxymeltose)
What is the 1st & 2nd line pharmacological treatments of HFrEF?
- 1st line = ACEi & beta-blocker (if intolerant of ACEi give ARB, if intolerant of both then give Hydralazine & isosorbide dinitrate)
- 2nd line = add MRA (spironolactone) if symptoms continue
What should be measured in patients being started on an ACEi & after each dose increase?
Urea, Creatinine, electrolytes & eGFR
Why are patients with heart failure typically intolerant of an ACEi or ARB?
Due to renal dysfunction or hyperkalaemia
What are the 3rd line treatment options for HFrEF?
Either one or more of the following options:
- Swab ACEi &/or ARB with sacubitril/ valasartan if ongoing symptoms
- Add digoxin if still symptomatic esp if they have AF
- Add hydralazine + isosorbide dinitrate if Afrocarribean & still symptomatic
- Add Ivrabradine if they have had a previous hosp admission within 12 months & have been stabalised for ≥ 4 weeks (must have sinus rhythm, HR ≥75 & LEVF
≤ 35%
- Consider ICD or cardiac resynchronisation therapy if LVEF ≤ 35% (esp if concurrent LBBB or prolonged QRS duration)
What patents with HF does Ivrabradine not work in ?
If they have AF
What is the treatment of HFpEF?
Tx = manage co-morbid conditions + given a personalised exercise based cardiac rehabilitation programme
What is the treatment of end-stage refractory heart failure and its indications/contraindications ?
Consider referral for LVAD/cadiac transplantation
Indications:
- Refractory cardiogenic shock
- Documented dependence on IV inotropic support to maintain adequate organ perfusion
- Peak VO2 < 10 ml / kg / min
- Severe symptoms of ischemia not amenable to revascularization
- Recurrent symptomatic ventricular arrhythmias refractory to all therapeutic modalities
Contraindications: age, severe comorbidity
