Flashcards in Heart failure Deck (42):
How is heart failure defined?
Cardiac output is inadequate for the body's requirements
What is systolic failure?
Inability of the ventricle to contract normally resulting in reduced cardiac output and ejection fraction <40%
What is diastolic failure?
Inability of the ventricle to relax and fill normally causing increased filling pressures. ejection fraction >50%
What causes systolic failure?
Ischaemic heart disease
What causes systolic failure?
What causes diastolic failure?
N.B. systolic and diastolic failure usually co-exist
What is congestive heart failure?
Left and right sided heart failure occurring concurrently
What are the symptoms of left ventricular failure?
Poor exercise tolerance
Paroxysmal nocturnal dyspnoea
Nocturnal cought, sometimes with pink frothy sputum
Wheeze- cardiac 'asthma'
What are the symptoms of RV failure?
Pulsation in neck and face (tricuspid regurgitation)
What are the causes of RV failure?
What is the definition of acute heart failure?
New onset or decompensation of of chronic heart failure characterised by pumonary and//or peripheral oedema with or without signs of peripheral hypotension
What is chronic heart failure?
Heart failure which develops and progesses very slowly. Venous congestion is common but arterial pressure is maintained well until very late
What is low output heart failure?
Cardiac output is low and fails to rise normally with exertion
What are the causes of low output heart failure?
1. Systolic and/or diastolic heart failure
2. Reduced heart rate- e.g. due to beta blockers, heart block or post MI
3. Negatively ionotropic drugs e.g. most anti-arrhythmic agents
1. Mitral regurgitation
2. Fluid overload e.g. NSAID causing fluid retention. Fluid overload may cause LVF in a normal heart if renal function is impaired or big volumes are involved e.g. IVI running too fast. This is more common if there is simultaneous compromise of cardiac function, and in the elderly
Chronic excessive afterload
1. Aortic stenosis
What is high output failure?
Output is normal or increased in the face of increased need. Failure occurs when needs are greatly increased and cardiac output cannot meet these needs. It will occur with a normal heart but even earlier if there is heart disease. It is rare.
What are the causes of high output heart failure?
What are the 'major' Framingham criteria?
Cardiomegaly (cardiothoracic ratio >50% on chest radiography)
Increased central venous pressure (16cmH2O at right atrium)
Weight loss >4.5kg in 5 days in response to treatment
Neck vein distention
Acute pulmonary oedema
What are the 'minor' Framingham criteria?
Bilateral ankle oedema
Dyspnoea on ordinary exertion
Tachycardia (heart rate >120/min)
Decrease in vital capacity by 1/3 from maximal recorded
According to the Framingham criteria, what does diagnosis of CHF require?
Either 2 major criteria
1 major criteria in conjunction with 2 minor criteria
General signs of heart failure?
Narrow pulse pressure
Displaces apex- LV dilation
RV heave- pulmonary hypertension
Murmurs of mitral or aortic valve disease
Wheeze- cardiac asthma
What investigations should be carried out?
BNP + ECG: if both are normal heart failure is unlikely
If either is abnormal, an echo is required
What features are seen on the CXR of a patient with heart failure?
Alveolar oedema (bat's wings)
kerley B lines (interstitial oedema)
Dilated, prominent upper lobe vessels
What drugs may exacerbate heart failure?
Why do NSAIDS exacerbate heart failure?
They may cause fluid retention
Why does verapamil exacerbate heart failure?
It is a negative ionotrope
What underlying illnesses/conditions may cause and/or exacerbate heart failure?
What lifestyle advice might you give a patient with chronic heart failure?
Reduce salt intake
Optimize weight and nutrition
What drugs are routinely used to treat chronic heart failure?
2. ACE inhibitor
3. Beta blocker
What diuretic drug(s) should be given in heart failure? What are the benefits?
1. Loop diuretics: furosemide or bumetanide
2. Reduce risk of death and worsening of heart failure and relieve symptoms
What are the side effects of Loop diuretics?
Hypokalaemia (if K is <3.2mmol/L, patient is predisposed to arrhythmias. Also CI for digoxin therapy due to increased digoxin toxicity); renal impairment
What is the main problematic side effect for patients of ACEi? How is this dealt with?
2. Angiotensin receptor blocker may be used as a substitute e.g. Candesartan
What are the benefits of using beta-blockers in heart failure? How should they be administered?
Decrease risk of mortality and have an additional benefit when used with ACEi's in patients with HF due to LV dysfunction.
Should be adminstered with caution 'start low and go slow' i.e. start on a low dose and wait at least 2 weeks between each dose increment.
What drugs might be used in patient show are intolerant of ACE-i and angiotensin receptor blockers?
Vasodilators: combination of hydralazine and isosobide dinatrare
What is the major side effect of hydralazine?
Drug induced lupus
How should a patient with severe oedema and HF be managed?
Daily weighing- aiming for weight loss of 1kg/day
If weight is not checked daily, a fluid balance chart should be filled in aiming for a negative balance of 1kg/day with fluid restriction of 1-1.5L per day
On examination what may be found in a patient with heart failure?
Chest pain- worse when lying flat
Distended abdomen- ascieties
Crackles in lung
May be displaced apex beat if heart is enlarged
What is a possible cause of intractable heart failure?
Taking drugs but at a suboptimum dose
How is intractable heart failure managed?
Switching furosemide to bumetanide may help- absorption may be better.
Consider admitting for:
1. Strict bed rest + Na and fluid restriction (<1.5L/24 hours)
2. Metolazone and IV furosemide
3. Opiates and IV nitrates may relieve symptoms
4. Weigh daily. Do frequent U&Es (beware low potassium)
5. Give DVT prophylaxis: heparin + TED stockings
What is the main biomarker of heart failure? Why is it used? What is its prognostic value?
Plasma BNP. It is closely related to LV pressure and reflects myocyte stretch. Its secretion is increased in heart failure. The higher the BNP the higher the risk of cardiovascular and all-cause mortality
What is the diagnostic threshold of the biomarker for heart failure?
BNP>100ng/L diagnosis heart failure
BNP < 50ng/L rules out heart failure
Is BNP higher in systolic or diastolic dysfunction?
Higher in systolic than isolated diastolic but highest in those with systolic and diastolic dysfunction