Heart Failure Flashcards
What is heart failure?
heart is unable to generate a cardiac output sufficient to meet the demands of the body without increasing diastolic pressure
there are many sub-categories of heart failure depending on clinical presentation (congestive), side (right vs left) or ejection fraction etc.
What are the most common causes of heart failure?
- Ischaemic heart dieseae (50% of HFrEF)
- Hypertension
- Valvular heart disease
- Arrythmias
- Diabetes
Many others
What is the most clinically relevant sub-classification of heart failure?
Ejection fraction
- Heart failure with reduced ejection fraction (< 40% Left Ventricular ejection fraction)
- Heart failure with preserved ejection fraction (>50% LVEF)
What is the main pathophysiology of Heart failure with reduced ejection fraction?
Reduced left ventricular contractility i.e. systolic ventricular dysfunction
Due to
1. Loss of cardiac myosittes (e.g. IHD)
2. high output failures
3. arrythmias
What is the underlying pathophysiology of heart failure with preserved ejection fraction?
Decreased ventricular compliance → diastolic ventricular dysfunction → reduced ventricular filling and increased diastolic pressure → decreased cardiac output
Due to
1. Hypertrophy due to HTN
2. impaired rleaxation e.g. tamponate/ constrictive pericarditis
What investigations should be ordered for a person in primary care suspected to have Heart failure?
pro-BNP
+ investigations for cause of HF (BP, ECG, Bloods incl. thyroid etc)
What are the referral pro-BNP thresholds for secondary care review in people with HF?
What is the first-line management of Heart failure with reduced ejection fraction
What should be done if they are not tolearated?
- ACEi and BB (+ SGLT2 but not yet in NICE guidelines)
- spironolactone (or aldosterone antagonist)
- diuretic for symptom control
(with monitoring of serum sodium + potassium + renal function before and after ACEi initiation/ dose increase)
+ ARB (i.e. sartans) if unable to tolerate ACEi
+ hydralazine and nitrate if intolerant to ACEi
What are some 2nd line treatments for heart failure with reduced ejection fraction?
- sacubitril/ valsartan (if persistent sx+ EF < 35%)
- Ivabradine (if HR > 75 and EF < 35%)
- nitrates, especially if afro-carribean
What is the MOA of sacubitril?
Sacubitril is a neprilysin inhibitor (neprylisin breaks down BNP, ANP i.e. products that are released by heart in response to stress and cause vasodilation)
Sacubitril –> less break down of these products –> vasodilation
What is the MOA of Ivabradine?
inhibits K+ funny channels therefore
- reduces HR
- –> longer diastole + increase O2 reply to myocytes + reduced O2 demand
What is the management for patients with acute heart failure who are haemodynamically stable?
- Sit patient up
- High-flow O2 (if hypoxic, conservative amounts associated with lower mortality than liberal oxygenation)
- IV loop-diuretics (40mg furosemide)
- Nitrate infusion (to reduce pre-load)
- Option to add a thiazide diuretics (monitor electrolytes and renal function)
- If unsuccessful: consider CPAP or BIPAP
