Chronic Heart Failure

Question 0

Primary Causes Heart Failure

Answer 0

Failure of heart muscle or Failure of heart valves

Question 1

Heart Failure Definition

Answer 1

Failure of the heart as a pump to meet the circulatory needs

Question 2

Types Heart Failure

Answer 2

Acute - Post MI Chronic

Question 3

Secondary/ Principle causes heart failure (3)

Answer 3

HYPERTENSION - Hypertrophy increasing cardiac work IHD - Impaired muscle function CARDIOMYOPATHIES - Alcohol, viral

Question 4

Heart Failure Precipitants (4)

Answer 4

Pregnancy Anaemia Hyper/ hypo- thyroidism Fluid retaining drugs e.g. Glucocorticoids; NSAIDs

Question 5

Heart Failure, neurohormonal adaptation - events (4)

Answer 5

Activation SNS Activation RAAS Activation ADH Activation ANP (atrial natriuretic peptide - promote sodium loss)

Question 6

Heart failure, neurohormonal adaptation - consequences (5)

Answer 6

Increased after load Increased circulating volume (increased preload and after load) Increased resistance - will lead to impaired renal function, more salt/ water retention with further activation of RAAS Neurohormonal adaptation –> myocyte dysfunction Vicious circle –> further impairs pump activity of the heart

Question 7

LEFT-SIDED FAILURE - Secondary cause & Consequence

Answer 7

Often secondary to hypertension Left ventricle impaired/ poor output leads to increase in ATRIAL/ PULMONARY VENOUS pressure with PULMONARY OEDEMA

Question 8

RIGHT-SIDED FAILURE - Causes (2)

Answer 8

Right ventricular output fails Due to Lung disease (cor pulmonale) Pulmonary valvular stenosis (valve between RV & Pulmonary aa)

Question 9

BIVENTRICULAR FAILURE - Causes (2)

Answer 9

Both chambers affected Disease (e.g. IHD) has affected both ventricles LV failure leads to pulmonary congestion, which may lead to RV failure

Question 10

Heart Failure - Signs & Symptoms (6)

Answer 10

Fatigue, listless Poor exercise tolerance (determines grade) Cold peripheries Low blood pressure? Reduced urine flow Weight loss

Question 11

LVF Signs and Symptoms

Answer 11

PULMONARY OEDEMA Dyspnoea - with a sensation of drowning (‘cardiac asthma’) Cough? Orthopnoea - breathlessness lying, relieved by sitting up (nocturnal?) Inspiratory crepitations on auscultation

Question 12

RVF Signs and Symptoms

Answer 12

Raised venous pressure Increased JVP Enlarged liver Oedema - ankles; if lying flat rises to thighs/ abdomen

Question 13

Heart failure Diagnosis

Answer 13

Symptoms & Examination Confirmed by echocardiogram –> ejection fraction s lines (lines possibly due to lympathetic distension)

Question 14

AF Cause

Answer 14

LV/ Valve failure leading to increased pressure in the left atrium leading to distension which ends of atrial fibrillation

Question 15

What is AF?

Answer 15

Stasis of blood and stagnation leading to THROMBI which may dislodge and move to cerebral circulation (risk TIA). Need prophylaxis against THROMBOEMBOLISM: warfarin/ aspirin.

Question 16

Heart failure treatment goals (6)

Answer 16

Identify/ treat CAUSE - valvular disease, IHD Reduce cardiac WORKLOAD Increase cardiac OUTPUT Counteract MALADAPTATION Relieve SYMPTOMS Prolong QUALITY OF LIFE - reduce hospitalisation

Question 17

Principles of pharmacological management of heart failure (4)

Answer 17

Stage dependent All patients with LV systolic dysfunction should receive ACEI All patient with oedema should receive a DIURETIC BETA-BLOCKERS now recognised as having an important role and should be used first line in moderate / stable heart failure

Question 18

ACEIs for heart failure

Answer 18

First line Prolong life

Question 19

Heart failure ACEIs - Action & Examples

Answer 19

E.g. Enalapril, lisinopril, ramipril Reduce arterial and venous vasoconstriction - reduce after and pre load Reduce salt/ water retention, hence reduce circulating volume Inhibit RAAS: Oppose neurohormonal adaptation May prevent cardiac remodelling

Question 20

How to use ACEIs in heart failure (4)

Answer 20

Low dose, then titrate upwards, may exceed licensed max dose Do NOT use with NSAIDs Monitor urea/ creatinine/ K+ before and during treatment Avoid in hypotension: systolic <100 mmHg

Question 21

Heart Failure ACEIs - WARNINGS

Answer 21

May cause severe hypotension - withdraw diuretic therapy for a few days before, and give at night. May cause deterioration of renal function in pre-existing renal disease

Question 22

AT1R Antagonists - Action & Examples &

Answer 22

Oppose action of A2 at AT1 receptor E.g. Candesartan, valsartan, losartan Equally as effective as ACEIs but don’t cause bradykinin cough

Question 23

Diuretic use in Heart failure

Answer 23

Mainstay of therapy, used when there is oedema (ankle/ pulmonary) Thiazides (bendroflumethiazide) - used in mild failure or in the elderly Loop diuretics (furosemide) - especially used in pulmonary oedema, may be given I.V. for rapid relief via vasodilatation

Question 24

Heart failure, Diuretic effects & action

Answer 24

Cause reduction in circulating volume - reduce pre load and after load Also cause VENODILATATION - reduce preload

Question 25

Heart failure, Diuretics - caution

Answer 25

Thiazides/ loop diuretics may cause hypokalaemia, though this is less of a problem if they are used WITH ACEIs.

Question 26

Beta blockers - role in heart failure & examples

Answer 26

Used to be contraindicated in CHF Now Central role: Reduce disease progression Reduce symptoms and mortality Used in STABLE, MODERATE FAILURE Metoprolol. BISOPROLOL. Nebivolol. Carvedilol (also alpha blocker/ antioxidant).

Question 27

Heart failure. Beta blocker action (4)

Answer 27

Reduce sympathetic stimulation, heart rate, O2 consumption Anti-arrhythmic activity reduces sudden death (also control rate in AF) Oppose neurohormonal activation (which leads to myocyte dysfunction) Especially useful in failure associated with ISCHAEMIA

Question 28

How to use beta blockers in heart failure

Answer 28

Start with low dose under supervision Then work up Symptoms may get worse at first May be appropriate in concurrent COPD if used with caution

Question 29

SPIRINOLACTONE - effects & use in heart failure

Answer 29

Aldosterone receptor antagonist Inhibits aldosterone effects on heart (fibrosis which stiffens heart) Effective agent which reverses LV HYPERTROPHY Low dose 25mg (non diuretic dose) reduces mortality by 35%

Question 30

Heart failure, DIGOXIN activity (3)

Answer 30

Positive inotrope by inhibiting Na+/K+ ATPase --\> Na+ accumulates in myocytes --\> exchanged with Ca2+ leading to increased contractility Impairs AV conduction and increases vagal activity (via CNS) This heart block and bradycardia is beneficial in heart failure with AF! [NB. Digoxin contra-indicated in concurrent heart block or bradycardia]

Question 31

How to use Digoxin in heart failure

Answer 31

Generally reserved for heart failure with AF (or when other treatments fail to control condition) Titrate dose to ensure ventricular rate does not fall below 60bpm as this indicates toxicity.

Question 32

Heart Failure Patient monitoring - RENAL FUNCTION (5)

Answer 32

Patients often elderly and renal function (GFR) may be impaired Important for drug handling - dose of digoxin is reduced in renal impairment (as digoxin is 2/3 renally excreted) Thiazides are INEFFECTIVE in renal failure ACEIs - used with care in mild-moderate failure, RF monitored. ACEIs - contraindicated in renovascular disease (renal artery stenosis - when BP and renal perfusion are maintained by high levels of renin)

Question 33

Heart Failure Patient Monitoring - POTASSIUM

Answer 33

Hypokalaemia is a major problem Side effect of thiazides/ loop diuretics Enhances digoxin effects (digoxin competes with K+ for pump site) Serious possibility of hyperkalaemia with ACEI if used with a K+ sparing diuretic

Question 34

Heart Failure Patient Monitoring - DIGOXIN TOXICITY

Answer 34

Major problem Narrow T.I. SEs: Anorexia, nausea (suggest too high dose), visual disturbances, diarrhoea Digoxin in AF, monitor pulse (\>60bpm)

Question 35

Treatment Algorithm - Evidence of LV dysfunction?

Answer 35