HF Flashcards
Define hf
Cardiac failure describes when cardiac output cannot meet metabolic demands.
What is congestive hf
combination of right and left sided ventricular failure
RF for hf
- revious myocardial infarction:the single greatest risk factor
- Non-modifiable risk factors: male gender, increasing age
- Cardiovascular risk factors: ischaemic heart disease, hypertension, hypercholesterolaemia, diabetes
- Valvular heart disease
- Renal failure: causes ‘high-output’ heart failure due to fluid overload
- Atrial fibrillation
What occurs in systolic hf
- The ejection fraction is not preserved: an ejection fraction of 40% or less would indicate systolic heart failure.
- The low stroke volume is due to the ventricles not pumping enough blood out.
What can cause a decrease in contractility for systolic hf
Mi infarction ant/lateral
dilated cardiomyopathy
IHD- less blood and o2 to the heart myocytes die
HTN-
What occurs in diastolic heart failure
In this case, the stroke volume is low but the ejection fraction is preserved. The reason for the low stroke volume is due to reduced filling of the ventricle (reduced preload)
What causes dystolic hf
- left ventricular hypertrophy
- restrictive caardiomyopathy
- valvular disease
- AF
How does left sided failure cause right sided failure
Blood starts backing up into the lungs causing pulmonary oedema and congestion. The pulmonary hypertension puts pressure on the right ventricle (cor pulmonale) and causes right-sided heart failure.
Frank starling law
In a normalheart, increased ventricular filling results in increased contraction via theFrank-Starling law→ increased cardiac output
What compensatory mechanisms occur in hf
- increase in hr
- RAAS activation
Symptoms of left sided hf
- Dyspnoea: particularly exertional
- Orthopnoea (SOB when lying flat) and paroxysmal nocturnal dyspnoea (SOB at night)
- Fatigue and weakness
- Cough with pink, frothy sputum
- Cardiogenic wheeze
signs of left sided hf
- Tachypnoea and tachycardia
- Cool peripheries
- Peripheral or central cyanosis
- Displaced apex beat
- Stony dull percussion: if an effusion is present
- Crackles on auscultation: coarse bi-basal crackles due to pulmonary congestion
- Third heart sound (S3)
right sided hf signs
- Due to backing up of fluid:
- Raised JVP
- Peripheral pitting oedema
- Hepatosplenomegaly
- Ascites
symptoms of right sided hf
- Fatigue and weakness
- Due to backing up of fluid
- Swelling in the legs
- Distended abdomen
severity criteria for hf
class 1 - no limits on activity , ordinary stuff does not cause SOB, palpitations
class 2- slight limits on activity , comfy at rest , but physical activity results in sob and fatigue
class 3- marked limit on activity , comfy at rest but mild activity causes problems
class 4- cant do any activity without discomfort , cardiac insufficiency at rest
Primary investigations for HF
- NT-proBNP: increased in chronic heart failure
- ECG:broad QRS complexes; evidence of left ventricular hypertrophy
- CXR:
What would CXR show for hf
- A-Alveolar oedema (batwing opacities)
- B- KerleyBlines
- C-Cardiomegaly
- D-Dilated upper lobe vessels
- E- Pleural effusion
Other investigations to consider
- FBC:anaemia may be a cause of ‘high-output’ heart failure
- U&Es: to investigate for renal failure as an underlying cause of heart failure; also U&Es monitored as ACEi’s and aldosterone antagonists can cause electrolyte abnormalities
- Blood lipids and fasting blood glucose:screen for hypercholesterolaemia and evidence of diabetes
1st line mx for hf
BB - bisoprolol + acei ramipril
2nd line mx for hf
aldosterone antagonist - spironolactone
3rd ;ine mx for hf
- crt
- icd
- digoxin
if acei is not tolerated what are the options
angiotensin receptor blocker candersartan or losarsartan
why would you give a spironolactone
when ejection fraction is low
complications of hf
- pleural effusion
- arrhythmias
- acute renal failure
