heart failure Flashcards
Heart failure (HF) definition
= is a syndrome and not a single pathological process in which there is impairment of the heart as a pump supporting physiological circulation.
s/s
Patients with heart failure will have the following features:
- symptoms typical of heart failure e.g. - breathlessness and exhaustion at rest or with less than the normal degree of exertion, fatigue and
- signs of fluid retention e.g. - pleural effusion, increased JVP, peripheral oedema and
- objective evidence of an abnormality of the structure or function of the heart at rest e.g. - cardiac murmurs, third heart sound
ways HF is classified
- low/high output
- L/R ventricular failure
- systolic/diastolic failure
- acute vs chronic
pathophys of heart failure
1. decreased CO initially = compensation
- starling effect dilates heart to improve contractility
- remodelling = hypertrophy
- release of ANP/BNP
- sympathetic activation
2. progressive decrease in CO
- progressive dilation => impaired contractility + functional valve regurg
- hypertrophy = relative myocardial ischemia
- RAS activation = na+ fluid retention
low output HF causes
ie. CO is low and fails to increase with exertion.
nb. systolic + diastolic features tend to coexist
1.pump failure
a) systolic failure [impaired cntraction of ventricles thus low CO, EF = <40%] due to:
- ischemia/mi
- dilated cardiomyopathy
- htn
- myocarditis
b) diastolic failure [inability of ventricles to relax and fill normally thus get increased filling pressure, EF = >50%
- pericardial effusion/tamponade/constriction
- cardiomyopathy- restrictive/hypertrophic
c)arrhythmias [low hr]
- bradycardia
- heart block
- tachycardias
- anti-arrhythmics
2. excessive pre-load [EDV]
- AR
- MR
- fluid overload
3. excessive after-load–ventricular pressure @ end of systole [ESP]
- AS
- HTN
- HOCM
high output HF causes
A.T.P!!
increased needs causes RVF initially, then LVF!
- anemia, AVM
- thyrotoxicosis, thiamine deficiency [beriberi]
- pregnancy, pagets
LVF causes
- ihd
- idiopathic dilated cardiomyopathy
- systemic htn
- mitral/aortic vale disease
- specific cardiomyopathies
LVF symptoms
symptoms:
- fatigue
- exertional dyspnoea
- orthopnoea + pnd
- nocturnal cough [and/or pink frothy sputum]
- wt loss + muscle wasting
signs:
- cold peripheries
- often in AF
- cardiomegaly w/displaced heart
- S3 + tachycardia = GALLOP RHYTHM
- cardiac asthma [wheeze]
- basal creps in both lung bases
RVF causes
- LVF
- cor pulmonale
- tricuspid/pulmonary valve disease eg. pulm stenosis
RVF s/s
symptoms:
- anorexia
- nausea
signs:
- raised JVP + jugular vein distention
- tender, smooth + pulsatile hepatomegaly
- pitting oedema up to thigs, sacrum, abdo wall
- ascites
- facial engorgement
nb: RVF/LVF may occur independently or together as CCF
acute vs chronic onset HF
acute
- new onset or decompensation of chronic
- peripheral/pulm oedema
- and/or evidence of hypoperfusion
chronic
- develops/progresses v slowly
- venous congestion = common
- arterial pressure maintained till v late
general summary of HF s.s
common symptoms are:
- breathlessness
- exertional
- at rest - can be orthopnoea and paroxysmal nocturnal dyspnoea (PND)
- fatigue
- exercise intolerance
- fluid retention - ankle swelling
- other non specific symptoms include:
- nocturia
- anorexia
- abdominal bloating and discomfort
- constipation,
- cerebral symptoms - confusion, dizziness and memory impairment
signs such as:
- tachycardia
- displaced apex beat
- third heart sound
- gallop rhythm
- reduced pulse volume
- pulsus alternans
- raised JVP –
- in right heart failure
- has a high predictive value in the diagnosis
- but is often absent
- oedema
- rales, or basal crepitations
- hepatomegaly
- ascites
Heart failure: NYHA classification
The New York Heart Association (NYHA) classification is widely used to classify the severity of heart failure:
NYHA Class I
- no symptoms
- no limitation: ordinary physical exercise does not cause undue fatigue, dyspnoea or palpitations
NYHA Class II
- mild symptoms
- slight limitation of physical activity: comfortable at rest but ordinary activity results in fatigue, palpitations or dyspnoea
NYHA Class III
- moderate symptoms
- marked limitation of physical activity: comfortable at rest but less than ordinary activity results in symptoms
NYHA Class IV
- severe symptoms
- unable to carry out any physical activity without discomfort: symptoms of heart failure are present even at rest with increased discomfort with any physical activity
HF ix
- chest radiology
🍒 ALVEOLAR SHADOWING - or classic perihilar ‘bat wings’ appearance
🍒 KERLY B LINES- thickened oedematous interlobular shadowing
🍒 CARDIOMEGALY- cardiothoracic ratio >50%
🍒 UPPER LOBE DIVERSION- upper lobe pulm vein dilation
🍒 EFFUSIONS-
🍒 FLUID IN THE FISSURES
-
the ECG - is recommended in every patient with suspected HF (1), may elucidate the cause of heart failure:
- left ventricular hypertrophy which may be caused by chronic hypertension or aortic stenosis
- evidence of ischaemic heart disease
- p-mitrale of mitral stenosis
-
echocardiography identifies:
- focal or diffuse myocardial dysfunction
- valvular disease
- pericardial disease
- left ventricular systolic dysfunction
-
biochemistry, haematology and urinalysis:
- defines electrolyte disturbances and assesses renal function
- fbc excludes anaemia
- tfts exclude thyrotoxicosis in patients with atrial fibrillation
- lfts excludes causes of oedema such as liver disease, nephrotic syndrome and acute renal failure
-
natriuretic peptides - testing for Brain-type natriuretic peptide (BNP), atrial natriuretic peptide (ANP), and N-terminal (NT)-ANP has been shown to increase the reliability of diagnosis of heart failure in primary care
- these peptides are released from ventricular myocytes in response to volume overload (stretch), and their concentration has been shown to an extremely sensitive marker for heart failure
Heart failure: diagnosis
NICE issued updated guidelines on diagnosis and management in 2010. The choice of investigation is determined by whether the patient has previously had a myocardial infarction or not.
Previous myocardial infarction
- arrange echocardiogram within 2 weeks
No previous myocardial infarction
- measure serum natriuretic peptides (BNP)
- if levels are ‘high’ arrange echocardiogram within 2 weeks
- if levels are ‘raised’ arrange echocardiogram within 6 weeks
what is serum bnp
Serum natriuretic peptides
B-type natriuretic peptide (BNP) is a hormone produced mainly by the left ventricular myocardium in response to strain.
Very high levels are associated with a poor prognosis.
Factors which alter the BNP level:
