Heart Failure Flashcards
(40 cards)
What re secondary and principle causes of heart failure?
Hypertension: hypertrophy increasing cardiac work
Ischaemic heart disease: impaired muscle function
Cardiomyopathies (alcohol, viral)
What might heart failure be precipitated by?
Pregnancy Anaemia Hyper + hypothyroidism Fluid retaining drugs: glucocorticoids NSAIDs
What neurohormonal adaption occurs in heart failure?
Sympathetic nervous system
RAAS (renin-angiotensin-aldosterone system)
ADH (anti diuretic hormone)
ANP (atrial natriuretic peptide) to promote sodium loss
What does neurohormonal adaptation lead to?
Increased afterload
Increased circulating volume (increased preload+afterload)
Increased resistance will lead to impaired renal function, more salt/water retention with further activation of RAAS
Myocyte dysfunction
What’s left-sided failure?
Often secondary hypertension
Left ventricle impaired (poor output) leads to increase in left atrial/pulmonary venous pressure with pulmonary oedema
What is right-sided failure often due to?
Lung disease (cor pulmonate) Pulmonary valvular stenosis
What’s biventricular failure?
Both chambers affected
Disease (IHD) has affected both ventricles
Left ventricular failure, leads to pulmonary congestion, may lead to right ventricular failure
What are the signs and symptoms of heart failure?
Fatigue, listless Poor exercise tolerance (determines grade) Cold peripheries Low blood pressure Reduced urine flow Weight loss
What are the symptoms of left ventricular failure?
Pulmonary oedema Dyspnoea Cough? Orthopnoea (nocturnal?) Inspiratory crepitations on auscultation
What are the symptoms of right ventricular failure?
Raised venous pressure
Increased JVP
Enlarged liver
Oedema- ankles, if lying down rises to thighs/abdomen
How is heart failure diagnosed?
Confirmed by echo- ejection fraction <45%
BNP levels (chronic heart failure)
CXR- cardiomegaly, pulmonary oedema, Kerley’s lines (due to sympathetic distension)
What is atrial fibrillation?
LV/valve failure leading to increased pressure in left atrium, leading to distension which leads to AF
What can AF cause?
Stasis of blood and stagnation leading to thrombi which may dislodge and move to cerebral circulation (risk of transient ischaemic attack TIA)
What do you need prophylaxis against in AF?
Thromboembolism
Warfarin or aspirin
What are goals of treatment for heart failure?
Identify/treat any cause (valvular disease/IHD)
Reduce cardiac workload
Increase cardiac output
Counteract maladaption
Relieve symptoms
Prolong quality life- reduce hospitalisation
Which patients should receive an ACEI?
All patients with left ventricular systolic dysfunction
What is used first line in moderate/stable heart failure?
Beta-blockers
What do ACEIs do?
Reduce arterial and venous vasoconstriction
Reduce after and pre-load
Reduce salt/water retention
Inhibit RAAS and so oppose neurohormonal adaptation and may prevent cardiac remodelling
What should you do when treating with ACEI?
Low dose then titrate upwards- may exceed licensed max dose
Do not use with NSAIDs
Monitor urea/creatine and K+ before and during treatment
Avoid in hypotension- systolic <100mmHg
What side effects do ACEIs cause?
Severe hypotension- withdraw diuretic therapy for a few days before; give at night
May cause deterioration of renal function in pre-existing renal disease
When are diuretics used?
Mainstay of therapy
Thiazides- used in mild failure or in the elderly
Loop diuretics (furosemide) especially in pulmonary oedema (iv given for rapid relief)
What do diuretics cause?
Cause reduction in circulating volume, reduce preload and afterload
Also cause venodilatation, reduce preload
What can thiazides/loop diuretics cause?
Hypokalaemia
Less of a problem if they are used with ACEIs
What are the common b-blockers used in heart failure?
Metoprolol
Bisoprolol
Carvedilol (also an a-blocker/antioxidant)
Nebivolol
