Acute heart failure

Question 1

Mechanism of acute heart failure

Answer 1

Left ventricle unable to adequately move blood
Backlog –> blood stuck in LA, pulmonary veins and lungs
Vessels are engorged - leak fluid - unable to resorb fluid
Causes pulmonary oedema
Interferes with gas exchange - SOB, o2 desaturation etc

Question 2

Acute left ventricular failure (LVF) triggers

Answer 2

Iatrogenic - fluids
Sepsis
MI
Arrhythmias

Question 3

Presentation of acute LVF

Answer 3

Rapid onset breathlessness
Exacerbated by lying flat, improves on sitting up
Type 1 respiratory failure
Cough - frothy white/pink sputum
Tachycardia
3rd heart sound
Bilateral basal crackles on auscultation (wet)
Hypotension - cardiogenic shock

Question 4

Right sided heart failure symptoms

Answer 4

Raised JVP
Peripheral oedema

Question 5

acute LVF investigations

Answer 5

Treat before diagnosis confirmed
ECG
ABG
CXR
Bloods (infection, kidney function, BNP, troponin if suspecting MI)
Echo

Question 6

What is BNP

Answer 6

B-type natriuretic peptide
Hormone released from ventricles when myocardium is stretched beyond normal range
Tries to relax smooth muscle in blood vessels - reduces systemic vascular resistance
Also a diuretic - reduces circulating volume

Question 7

Causes of high BNP

Answer 7

Tachycardia
Sepsis
PE
Renal impairment
COPD

Question 8

LVF CXR findings

Answer 8

Cardiomegaly (cardiothoracic ratio of > 0.5)
Upper lobe venous diversion (more blood in upper lobes due to back pressure)
Fluid leakage causing:
- Bilateral pleural effusions
- fluid in interlobar fissures
- fluid in septal lines (Kerley lines)

Question 9

LVF management

Answer 9

Pour SOD
Pour away IV fluids - monitor fluid balance
Sit up
Oxygen if sats falling
Diuretics - IV furosemide 40mg stat

Question 10

LVF management if severe

Answer 10

Opiates - vasodilators
NIV - CPAP or intubation
Inotropes (noradrenalin) - strengthen force of heart contractions - need close monitoring - ICU