lecture 3 - heart failure Flashcards
define heart failure
• Pathophysiological definition
– inability of the heart to pump sufficient oxygenated blood
to the metabolising tissues despite an adequate filling
pressure
• Clinical definition
– clinical syndrome consisting of breathlessness, fatigue and
oedema caused by cardiac dysfunction (usually left
ventricular systolic dysfunction)
HFREF vs HFPEF?
• Heart failure with reduced ejection fraction (HFREF)
– syndrome of heart failure with objective evidence of LV systolic
dysfunction (LVSD)
– REST OF TALK/SLIDES ARE ABOUT THIS
• Heart failure with preserved ejection fraction (HFPEF)
– syndrome of heart failure with objective evidence of normal LV systolic function (though frequently with evidence of diastolic dysfunction)
– poorly understood, no evidence that any current treatment has impact
on mortality in the long term
(High-output HF: AV fistula, Paget’s disease, anaemia)
HF mortality
32% die within 1 year; thereafter mortality 10% per year
(similar to colorectal cancer, worse than breast cancer)
Patients often have significant co-morbidities (e.g. chronic
kidney disease and COPD) that complicate treatment
• Median age at diagnosis is 76 years
causes of HF
• Coronary artery disease: infarction, adverse remodelling,
stunning, hibernation
• Hypertension
• Valvular heart disease
• Congenital heart disease
• Cardiomyopathies: dilated, restrictive, hypertrophic, peripartum
• Cardiac infiltration: amyloidosis, sarcoidosis, iron overload
(e.g. haemochromatosis)
• Toxins: alcohol, anthracyclines, abstruzimab
• Infection: viral myocarditis, HIV, Chagas, Lyme disease
• Nutritional deficiencies: selenium, thiamine, beri-beri
symptoms of left heart failure
• Pulmonary congestion – exertional dyspnoea – orthopnoea – paroxysmal nocturnal dyspnoea – haemoptysis
• Systemic hypoperfusion
– fatigue and lethargy
– postural dizziness
symptoms of right heart failure
• Systemic congestion – ankle swelling – weight gain – abdominal distension – abdominal pain – dyspnoea – cardiac cachexia
• Pulmonary hypoperfusion
– no clinical sequelae
New York Heart Association classification of HF
• NYHA I: no limitation of physical activity (ordinary activity
does not cause undue breathlessness or fatigue)
• NYHA II: mild limitation of physical activity (comfortable at
rest but ordinary activity results in breathlessness or fatigue)
• NYHA III: moderate limitation of physical activity
(comfortable at rest but less than ordinary activity results in
breathlessness or fatigue)
• NYHA IV: severe limitation of physical activity (breathlessness
and fatigue at rest)
signs of Left heart failure
• Pulmonary congestion
– tachypnoea
– basal fine insp crackles
– wheeze
• Systemic hypoperfusion – cold clammy peripheries – feeble pulses, tachycardia, pulsus alternans – hypotension ®shock
• Auscultatory signs
– faint first heart sound
– third or fourth heart sounds
signs of right heart failure
• Systemic congestion – peripheral pitting oedema – raised JVP – signs of ascites – signs of liver congestion – signs of pleural effusions
• Pulmonary hypoperfusion
– no clinical sequelae
AHF – Management
Assessment
• Detailed history and examination
• Arterial blood gases (if needed to guide O2 therapy)
• Venous bloods – routine biochemistry (U&Es, LFTs, troponin, CK,
TSH, glucose) and haematology (FBC, clotting, ±anaemia screen)
• ECG
• Chest x-ray
• Echocardiogram (or equivalent imaging) – to detect LV systolic
impairment, identify cause and assess severity
• Additional tests in some cases – other blood tests (e.g. HIV, ferritin,
autoimmune screen), cardiac MRI, myocardial perfusion
scintigraphy, coronary angiography and right heart study
CXR signs of heart failure
- cardiomegaly
- batwing perihilar shadowing
- upper lobe blood diversion
- septal lines (Kerley B lines)
- fluid in horizontal fissure
- pleural effusion
Role of Echocardiography in heart failure
• Diagnosis of heart failure
– detection of LV and/or RV systolic
and/or diastolic impairment
• Assessment of severity – assessment of LV and RV systolic function, diastolic function and dimensions – assessment of dyssynchrony
• Helps in determining cause – valvular pathology – cardiomyopathies – regional wall motion abnormalities
AHF – Management
Principles of treatment
• Treat congestion – diuretics, vasodilators, ultrafiltration
• Treat hypoxia / distress – opiate, oxygen, ventilatory support, treat
congestion
• Treat hypotension / hypoperfusion – inotropes, intra-aortic balloon pump (IABP), ventricular assist device (VAD), cardiac transplantation
• Treat precipitant(s) – e.g. acute coronary syndromes, arrhythmias,
acute mechanical problem (e.g. ruptured mitral valve), myocarditis,
anaemia, etc
- Do not stop HF drugs unless good reason to (e.g. hypotension)
- Refer to heart failure specialist
AHF – Management
Summary of treatment (in “usual” cases)
- Sit up
- Oxygen to keep SaO2 ³95% (or 88-92% if chronic lung disease)
- IV furosemide (40-80 mg as bolus, consider infusion)
- ± IV glyceryl trinitrate infusion (0-10 mg/h titrated according to BP)
• ± IV diamorphine (2.5-5 mg as bolus) with IV anti-emetic (e.g.
metoclopramide 10 mg as bolus)
- Monitor urine output (insert urinary catheter if necessary)
- CPAP or intubation/ventilation if severe type 1 respiratory failure
- Inotropes if cardiogenic shock
- Treat underlying cause/precipitant
- Start prognostic drugs once LVSD confirmed on echocardiogram
Drugs with mortality and morbidity benefits in HF
First line • ACE inhibitors (ACEi) • Beta blockers (BB) • Mineralocorticoid receptor antagonists (MRA)
Second line
• Hydralazine/isosorbide dinitrate
• Angiotensin receptor blockers (ARB)
Drugs with morbidity only
benefit in HF
- Digoxin
- Ivabradine
- Diuretics
- Inotropes
what type of corticoid is aldosterone
mineralocorticoid
what is Hydralazine
• Hydralazine is an arteriolar dilator with an uncertain mode of
action
what is Isosorbide dinitrate (ISDN)
• Isosorbide dinitrate (ISDN) is a venous and arterial dilator,
that acts by relaxing smooth muscle via nitric oxide
how does digoxin work
• Inhibits Na-K ATPase, resulting in secondary activation of Na-
Ca membrane exchange pump, resulting in positive inotropic
effect
• Also reduces AV nodal conduction
how do loop diuretics work
e.g. furosemide –
inhibit Na-K-2Cl carrier in thick
ascending loop of Henle
how do thiazide diuretics work
thiazide (synergistic adjuncts) e.g.
bendroflumethiazide – inhibit active
reabsorption of Na in distal convoluted
tubule
what are inotropes
• Inotropes are drugs that increase the force of contraction of
the heart
• Indicated in cardiogenic shock
• Examples:
– dobutamine – non-selective b1 and b2 receptors
(adrenergic) agonist
– milrinone / enoximone – phosphodiesterase type III
inhibitors (inodilators)
– levosimendan – calcium channel sensitiser
– dopamine / dopexamine – DA1 receptor agonist
Non-pharmacological Treatment of HF
• Education
• Lifestyle modification:
– stop smoking
– reduce alcohol intake (if excessive) – abstain if alcoholrelated
DCM
– reduce weight (if overweight)
– limit salt intake (<1.5-2 litres/day) if recurrent fluid
retention
• Exercise – cardiac rehabilitation
• Vaccination – pneumococcal and influenza vaccinations
Other Treatment
• Cardiac resynchronisation therapy (CRT) = biventricular
pacemaker – severe heart failure (LVEF £35%) and left bundle
branch block (LBBB) on optimal medical therapy
• Coronary revascularisation – heart failure with significant (i.e.
symptomatic) coronary artery disease
• Heart transplantation – end-stage heart failure
• Ventricular assist device – bridge to transplantation, bridge to
recovery in some patients with DCM, destination therapy
(note destination therapy is not licensed in UK)
• Implantable cardioverter defibrillator (ICD) – as primary
prophylaxis in selected patients
LV lead
RV (ICD) lead
RA lead
CRT-D
