Heart Failure Flashcards
3 symptoms of heart failure in the definition
Dyspnoea
Fatigue
Oedema
Systolic dysfunction
- Circulatory volume increases, heart dilates, force of contraction decreases and CO decreases
- Decreased CO activates RAAS which increases H20 and water retention
- RAAS activated = circulatory volume increases and cardiac performance decreases further
- Heart dilates = cardiac myocytes undergo hypertrophy which leads to fibrosis = further weakened heart
Heart failure usually occurs (when)…
- Following sustained hypertension (diastolic dysfunction/preserved ejection fraction HF)
- Following myocardial damage i.e. an MI (systolic dysfunction)
In heart failure, RAAS and Activation of sympathetic system…
RAAS
- causes release of angiotensin II and aldosterone
- Result is salt and water retention, vasoconstriction and hypertrophy of cardiac myocytes
ACTIVATION OF SYMPATHETIC SYSTEM
- causes release of noradrenaline and adrenaline
- Result is vasoconstriction, stimulates renin release which feeds into RAAS and myocyte hypertrophy
Risk factors for HF
Age Hypertension (LVH) Obesity Chronic Heart disease Hyperlipidaemia Coronary artery disease Valvular heart disease Alcoholism Infection (viral) Congenital heart defects Smoking High or low haematocrit level Obstructive sleep apnoea
Causes of LVSD
Ischaemic heart disease (usually MI)
Dilated cardiomyopathy (DCM)
Severe aortic valve disease or mitral regurgitation
Dilated cardiomyopathy is an umbrella term
Inherited Toxins e.g. alcohol Viral (acute myocarditis or chronic DCM) Other infective; HIV, Lymes Disease Systemic disease e.g. sarcoidosis Muscular dystrophies Peri-partum cardiomyopathy Hypertension Isolated non-compaction Hypertension Tachycardia related cardiomyopathy Right ventricular pacing induced cardiomyopathy End stage hypertrophic cardiomyopathy End stage arrythomogenicity RV cardiomyopathy
Heart failure is a systemic disorder which involves
- Cardiac dysfunction
- Renal dysfunction
- Skeletal muscle dysfunction
- Systemic inflammation
- Neurohormonal activation (mostly maladaptive)
Symptoms of HF
Oedema Tachycardia Raised JVP Chest crepitations or effusions 3rd heart sound Displaced or abnormal apex beat
Diagnosing someone with LVSD;
DETAILED HISTORY: - Hillwalkers (lymes disease) - IVDA (HIV test) - Consider familial DM ?Antibodies/viral serology; ferritin Exclude renal failure, anaemia, TFTs Consider other causes; sarcoid, muscle dystrophy etc ECG ECHO sometimes CXR ?Coronary angiogram CT coronary angiogram Need to exclude phaeochromytoma Cardiac MRI Most patients should be assessed by a cardiologist
Positive diagnosis of HF
Symptoms and signs of HF (rest or exercise)
Objective evidence of cardiac dysfunction
Response to therapy (diuretics)
Investigations for HF
12 lead ECG
ECHO
Radionucleotide venticulography (RNVG/MUGA)
MRI
Left ventriculography
BNP screening (elevated in heart failure)
LVEF levels
Normal 50-80%
Mild 40-50%
Moderate 30-40%
Severe <30%
Pharmacological treatment of HF (due to LVSD)
Diuretics ACE inhibitors or ARBs Beta blockers Aldosterone receptor blockers Some patients ARNI (angiotensin receptor nephilysin inhibitor: sacubitril valsartan)
Types of Heart failure
Systolic Heart failure: HFrEF
Diastolic heart failure: HFpEF
Chronic heart failure
