Heart Failure Flashcards
Definition of heart failure
A clinical syndrome comprising of dyspnoea, fatigue or fluid retention due to cardiac dysfunction, either at rest or on exertion, with accompanying neurohormonal activation
Symptoms
Dyspnoea
Fatigue
Oedema
Reduced exercise capacity
Signs
Oedema Tachycardia Raised JVP Chest crepitations or effusions 3rd heart sound Displaced or abnormal apex beat
3 things patient must have to diagnose heart failure
- symptoms or signs of HF
- Objective evidence of cardiac dysfunction
- Response to therapy (diuretics)
How can you get objective evidence of cardiac dysfunction
Echocardiography Radionuclide ventriculography MRI ECG BNP (brain natriuretic peptide)
what could be used as a potential screening test for heart failure
elevated BNP
What 3 causes of heart failure to remember
Ischaemic heart disease
Dilated cardiomyopathy - Left ventricular systolic dysfunction
Severe aortic valve disease or mitral regurgitation
What would you try and identify and quantify in an echocardiography
LV systolic dysfunction
Valvular dysfunction
Pericardial effusion/ tamponade
Diastolic dysfunction
Left ventricular hypertrophy
Atrial/ventricular shunts/ complex congenital heart defects
Pulmonary hypertension/ right heart dysfunction
What is the LV ejection fraction
Stroke volume over end diastolic volume
Normal, mild, modertate and severe LV ejection fractions
Normal: 50-80%
Mild: 40-50%
Moderate: 30-40%
Severe: <30%
How might you find out the LVEF
Biplane Modified Simpson’s Rule
Radionucliotide angiography
Cardiac MRI
Grading of hypertrophy based on New York Association classification
I - No limitation, no symptoms during usual activity
II - Mild limitation, comfortable with rest or mild exertion
III - moderate limitation, comfortable only at rest
IV - severe limitation, any physical activity brings on discomfort and symptoms occur at rest
Why can someone with HF have same cardiac output as some
Dilated heart so larger end diastolic volume but smaller percentage of stroke volume
Also more bpm
How do neurohormonal changes come into heart failure?
Renin-angiotensin-aldosterone system is activated and salt and water is retained
Effects of the renin-angiotensin-aldosterone system in heart failure
Salt and water retention
Adverse haemodynamics
LV hypertrophy/remodelling and fibrosis
Hypokalemia and hypomagnesaemia
Heart failure definition (other lecture)
A state in which the heart is unable to pump blood at a rate commensurate with the requirements of the tissues or can do so only from high pressures
Risk factors for heart failure
Coronary artery disease History of previous MI Hypertension Valvular heart disease Alcoholism Diabetes Congenital heart defects
Obesity
Age
Reduced or falling vital capacity
Smoking
What happens to cardiac myocytes as the heart starts to dilate
They undergo hypertrophy and then fibrosis and the heart is further weakened
What does the sympathetic system do in heart failure
Causes the release or noradrenaline and adrenaline
- vasoconstriction
- stimulate renin release
- myocyte hypertrophy
Two aims of treatment
To improve symptoms
To improve survival
What two drugs improve symptoms
Diuretics
Digoxin
What 3 drugs improve symptoms and survival
ACE inhibitors/ ARBS
Spironolactone
Valsatan-sacubitril
What 2 drugs improve survival
Beta-blockers
Ivabradine
Give an example of a loop diuretic and what does it do?
FUROSEMIDE
Removes excess salt and water by inhibiting the sodium/potassium/chlorine transporter in the Loop of Henle
