Heart failure Flashcards
Define heart failure
The inability of the heart to deliver O2-rich blood at a satisfactory rate for the tissues’ metabolic requirement
What are the 2 types of heart failure?
- Systolic
- Diastolic
Describe systolic pathophysiology
The ventricle’s ability to contract is reduced
Describe diastolic pathophysiology
There is impaired relaxation and ventricular filling
Describe the pathophysiology of heart failure
- It begins when the heart’s ability to pump blood is affected (it can be acute or chronic)
- This leads to a reduced ejection fracture (below 50% is abnormal) and therefore reduced cardiac output
- Compensatory mechanisms then activate
- Soon these compensatory mechanisms fail, and the heart undergoes cardiac remodelling
- These remodelling changes can improve cardiac output temporarily, but these will also eventually fail
Describe the compensatory mechanisms in HF
- RAAS – Release of renin -> RAAS cascade -> vasoconstriction and water/Na retention
- Sympathetic Nervous System (SNS) – Release of catecholamines (adrenaline) -> increased heart rate and heart contractility
Describe the cardiac remodelling in HF
- Hypertrophy – Heart gets bigger
- Dilation of the Chambers – Heart chambers get bigger; however, this can lead to the thinning of the cardiac wall
Describe right HF
- The right ventricle doesn’t pump blood properly, leading to a backlog of blood going into the heart
- Causes increased systemic venous pressure, resulting in peripheral oedema
Describe left HF
- The left ventricle doesn’t pump blood properly leading to a backlog of blood into the pulmonary vessels and lungs
- Causing increased pulmonary pressure, resulting in pulmonary oedema
What are risk factors of HF?
Age (65+)
Smoking
Obesity
Previous MI
Male sex
How is HF classified?
NY Heart Association Heart Failure Severity
- Class I: no symptoms with physical activity.
- Class II: slight limitation of physical activity by symptoms.
- Class III: less than ordinary activity leads to symptoms.
- Class IV: inability to carry out any activity without symptoms
What are symptoms of HF?
Breathlessness
Cough (with frothy white/pink sputum)
Orthopnoea (breathlessness when lying flat)
Paroxysmal nocturnal dyspnoea (waking up gasping for air)
Peripheral oedema
Fatigue
What are signs of HF?
- Tachycardia
- Tachypnoea(raised respiratory rate)
- Hypertension
- Murmurs(indicating valvular disease)
- 3rd heart sound
- Bilateral basal crackles (indicating pulmonary oedema)
- Raised jugular venous pressure (caused by a backlog on the right side of the heart)
- Peripheral oedema
How do you diagnose HF?
- Blood Test (High NT-proBNP)
- ECG
- Chest x-ray
- ECHO – analyse chamber dimensions (GOLD STANDARD)
What are causes of HF?
- Coronary Heart Disease (TOP CAUSE)
- Hypertension (TOP CAUSE)
- Valvular Heart Disease
- Arrhythmias
What are conditions that cause increased demand on the heart?
Anaemia
Pregnancy
Sepsis
Hyperthyroidism
What is seen on CXR for HF?
ABCDE
A - Alveolar Bat Wing
B - B lines
C - Cardiomegaly
D - Dilated upper vessels
E - Effusion (pleural)
What is conservative treatment of HF?
- Lifestyle changes to reduce BMI
- Smoking & alcohol reduction/cessation
What is the first line treatment for HF?
ABAL mnemonic
A- Ace inhibitor
B- Beta blocker
A – Aldosterone antagonist (only given when A+B don’t control the symptoms)
L- Loop diuretics
When should ACE inhibitors not be given?
Ace inhibitors should not be given to patients with valvular heart disease unless indicated by a specialist
What should be given in place of ACEi?
Angiotensin receptor blockers (ARBs) can be used in place of ace inhibitors in patients who cannot tolerate them
Which classes of drugs do patients have to have their U&E’s measured?
Patients on diuretics, ace inhibitors, and aldosterone antagonists
Which classes of drugs can cause fatal hyperkalaemia?
ACE inhibitors and aldosterone antagonists
What are specialist treatments for HF?
- SGLT2 inhibitor
- Sacubitril with valsartan
- Ivabradine
- Hydralazine with a nitrate
- Digoxin
