Heart Failure Flashcards
What is heart failure?
- inability of heart to pump blood around the body
- cardiac output is low
What is the most common cause heart failure?
- cardiomyopathy (heart muscle disease)
- specifically ischemic heart disease
How may people are diagnosed with heart failure per year in the UK?
- incidence = 200,000
- prevelence = 900,000
What is the life expectancy of a patient with heart failure in the UK?
- 5 years
- admitted with advanced heart failure <1 year despite treatment
Heart failure can be subdivided into 3 clinical syndromes. What are these 3 syndromes?
1 - chronic heart failure = peripheral oedema
2 - acute heart failure = pulmonary oedema
3 - cardiogenic shock = low BP (<90mmHg)
Left systolic heart failure is the most common cause of heart failure. What can happen to the left ventricle as a result of this?
- left ventricular weakness / dilation
- means any subsequent contractions are weaker
There are a lot of conditions that cause left systolic heart failure, but what is the main cause?
- ischaemic heart disease (MI/ischaemia)
What is the volume in the left ventricle dependent on?
- preload = blood returning to heart
- afterload = systemic vascular resistance
How are we able to measure left ventricle function?
- measure left ventricle ejection fraction
- LV ejection fraction = SV / end diastolic volume
How can you calculate end diastolic volume?
- stroke volume - end systolic volume
In systolic left sided heart failure, what is the first common sign of left sided heart failure?
- reduced stroke volume
- due to decreased left ventricle contractility (WEAK)
In systolic left sided heart failure, stroke volume is decreased due to a weakened left ventricle. This means that more blood is left in the left side of the heart at the end of systole. What does this do to the diastolic pressure in the left side of the heart?
- increased blood left in heart
- causes increased left sided diastolic pressure
If the increased blood left in the heart causes an increase in left sided diastolic pressure, what does this do to left ventricle end diastolic volume?
- LV becomes dilated due to volume overload
- this results in a reduced LV ejection fraction
In a normal heart the left ventricle ejection fraction is normally between 55-70%. What is the LV ejection fraction in systolic heart failure heart failure?
- <40%
In heart failure there is a forwards and backwards heart failure. In patients with heart failure there is an increase in the pressure in the left ventricle, causing a reduction in LV contractility. What does this do to cardiac output?
- reduces cardiac output
- this is a forward theory
In heart failure there is a forwards and backwards heart failure. In patients with heart failure there is an increase in the pressure in the left ventricle, causing a reduction in LV contractility. What does this do to pressure in the left atrium and pulmonry veins?
- increases pressure in LA and PV
- pressure moves backwards
- backwards theory
What are the common sysmptoms that patient present with in heart failure?
- breathlessness on exertion
- Orthopnoea (breathlessness lieing down)
- Paroxysmal nocturnal dyspnea (PND) (breathlessness sleeping)
- Fatigue due to low cardiac output
- Leg swelling (oedema) due to change in pressures
What method is used to stratify the severity of heart failure?
- New York Heart Association (NYHA)
- class 1-4
In patients with heart failure, what are 3 simple non invasive assessments can clinicians perform?
- increased jugular vein pressure (JVP)
- pitting shows oedema (pulmonary and peripheral)
- lung ascultation gives lung crackles (air moving through fluid)
What are the first 2 investigation clinicians perform in patients with suspected heart failure?
- ECG
- Brain Natriuretic Peptide (BNP)