Definition
Cardiac index < 1.8L/min/m2
Classification
Killip ranking of heart failure originally done for 30-day mortality post-MI
- Asymptomatic 5% mortality
- Mild–mod (S3/creps) 15-20% mortality
- APO 40% mortality
- Moribund/shocked 80% mortality
New York Heart Association (NYHA)
- I – Symptoms on abnormal exertion
- II – Symptoms on ordinary activity
- III – Symptoms on less-than-usual activity
- IV – Symptoms at rest
Causes
High output (Rare)
- Fever, anaemia, AV fistula or malformation, thyrotoxicosis, beriberi (Thiamine [B1] deficiency), Paget’s disease
Low output
- Mechanical:
- Valve lesions, tumours, tamponade. Congenital abnormalities
- Myocardial:
- Ischaemia/infarct, Toxins (colchicine, alcohol, negative inotropes, metabolic disturbances, chemotherapeutics), cardiomyopathy
- Pressure related:
- HT, massive PE
Systolic failure (impaired ability to contract, LV Ejection Fraction<0.45):
- IHD
- Severe systemic HTN
- Valve disorders – congenital, 2° to papillary mm. dysfunction, Rh Fever, endocarditis
- ASD, VSD
- AI, MS
- LA tumour
- HOCM, other cardiomyopathies
Diastolic failure (impaired ability to fill in diastole):
- Mainly HT
- Also HOCM, aortic stenosis, restrictive cardiomyopathy, infiltrative disease – sarcoid
Arrhythmias
- AF, SVT, VT
Right Ventricular failure
- LVF, RV MI, PE/COPD, pulm valve disease, TR, congenital L→R shunts
Assessment
History
- Asymptomatic (80%)
- Dyspnoea (SOB, SOBOE), orthopnoea/PND, peripheral oedema/RUQ pain/anorexia if RVF
- Precipitants – ischaemia, arrhythmias, infection, anaemia, poor compliance, COPD, drug effects, PE, thyrotoxicosis, pregnancy
Examination
- Relative tachy, displaced apex, S3/S4, 2° TR or MR
- LVF – ↑RR, fine insp creps, rising from base, cardiac asthma, pleural effusions
- RVF – ↑JVP, Kussmaul’s sign, hepatomegaly, ascites, peripheral oedema & pleural effusions
Investigations
- Bloods:
- FBC, UEC, Cardiac markers, BNP (LVF release>RVF, <100pg/ml = HF unlikely, >500pg/ml = likely. Often equivocal. False pos from DDx of HF incl PE, RF, AF & sepsis limits use in ED.)
- ECG:
- for arrhythmias / IHD / LBBB
- Imaging:
- CXR (↑CTR, Kerley B’s, pulm oedema). Echo
- Special:
- Bioimpedance CO monitoring, TFT if indicated
DDx
- COPD/Asthma
- Non-cardiogenic pulm oedema
- Sepsis
Management
Priorities
- Pulm oedema – maintain oxygenation
- Hypotension – fluid Mx & inotropes
- Ischaemia – reperfusion strategies
- Treat underlying cause if possible
- RVF – non-urgent oedema reduction
Oxygenation
- Sit upright (↑lung vent) +/- legs over side of bed (venous return/preload)
- High flow O2
- CPAP 10mmHg/BiPAP 15/5mmHg
- IPPV if NIPPV fails or GCS<9, unprotected airway
Haemodynamic – IVC & consider invasive monitoring if shocked.
- Nitrates – GTN 150-300mcg sl or infusion (start 300mcg/hr & titrate up to 2-12mg/hr). ↓pre- & after-load & coronary dilation/perfusion. Beware ↓BP, RVF, HOCM, AS.
- Fluid – restrict in overload; careful challenge if shock & no APO: 100-250ml 0.9% saline.
- Inotropes – if BP ok: dobutamine 2-20mcg/kg/min IV. If ↓BP: **dopamine 2-20mcg/kg/min. Even adrenaline or **NA 0.5-30mcg/min (0.02-1mcg/kg/min) but ↑myocardial O2 demand
- Diuretics – frusemide 40mg IV or 1-2x usual dose. Not 1st line – consider if fluid overload
- PCI – if AMI present (or thrombolysis if PCI not avail/CI)
- Treat arrhythmias – medical Rx or DC shock
- Mechanical support – intra-aortic balloon pump
- Digoxin, ACEI, statin, thrombosis prophylaxis, ±β-blocker (carvedilol) for chronic therapy
- Morphine 0.5-2.5mg IV – once a std Rx, now increasingly controversial with questions over haemodynamic effects and reports of poorer outcomes. Considered in low doses as anxiolytic if very agitated, BUT risk of resp depression. Fentanyl a possible alternative.
- Nesiritide – recomb DNA BNP – probably useless and ?assoc with ↑mortality
Prognosis
- 50% mort post APO episode
- F>M
- Annual mort NYHA Class II – 10%, III – 20%, IV – 40%