Cardiovascular Disorders Flashcards
What three areas can cardiovascular disorders affect?
Muscular
Conduction
Vasculature
What are cardiomyopathies?
Disorders that affect cardiomyocytes or cardiac muscle function
Give examples of cardiomyopathies?
Heart failure - Reduced ejection fraction - Preserved ejection fraction Take tsubo syndrome Dilated cardiomyopathy Hypertrophic cardiomyopathy
Define heart failure
Heart unable to maintain adequate circulation for metabolic requirements of body
Define preserved ejection fraction
Preserved ejection fraction (HFpEF): EF ≥ 50%, ↓ diastolic function
Define reduced ejection fraction
Reduced ejection fraction (HFrEF): EF ≥ 40%, ↓ systolic function
Can be treated pharmacologically
What is normal ejection fraction?
60-70%
What happens in reduced ejection fraction heart failure
Systolic disfunction Heart cannot pump as well Insufficient strength Dilated left ventricle Thinning of muscle Eccentric development of muscle- myocytes develop alongside each other
What happens in preserved ejection fraction heart failure
Increase in muscle mass of left ventricle
Can pump but not relax
Diastolic disfunction
Concentric development of muscle- myocytes develop on top of each other
What are the underlying causes of heart failure?
Obesity Ischaemia Myopathy Hypertension Valve disease
What would tend to cause more preserved EF HF?
Hypertension
What would tend to cause more reduced EF HF?
Myocardial infarction
What are the effect of HF on cardiac output and life expectancy?
↓ cardiac output, venous blood accumulation
Poor prognosis: 50% mortality rate < 5 years
What are the ECG findings for Heart failure?
Non-specific Multiple potential ECG abnormalities Linked to potential cause: e.g. Hypertrophy or Atrial Fibrillation Enlarged QRS complex Not diagnostic marker
What is a a diagnostic marker?
Elevated natriuretic peptide levels
What are general symptoms of heart failure?
- breathlessness, fatigue & fluid retention caused by cardiac dysfunction
What is tako tsubo syndrome named after?
A Japanese octopus pot
What is tako tsubo syndrome?
Left ventricular enlargement Apex balloons Symptoms mimic MI Takes on octopus pot shape Arrises later in life Caused by stress/trauma "broken-heart syndrome" 80-90% female
What is the effect of tako tsubo on cardiac output and life expectancy?
↓Q, ejection fraction ~ 40%.
5% mortality
What are the ECG findings of Tako Tsubo?
ST segment elevation
typically associated with MI
But no increase in MI markers
What are the general symptoms of Tako Tsubo?
Chest pain
Increased cardiac biomarkers
Normal blood vessels
Define conduction abnormalities
disorders that affect bioelectrical transmission along the heart
Give examples of conduction abnormalities?
Atrial Arrhythmias - Atrial fibrillation -WPW Tachycardias -Sinus -Atrial Ventricular arrhythmias - Ventricular fibrillation - Torsade de pointes Conduction block - AV block (types 1, 2 & 3) - Bundle branch block
What is a normal ECG? (Atrial)
P-wave
Atrial contraction
Normal – followed by a QRS complex
What is a normal EGG? (Conduction)
P-R interval
Conduction through AV node
Normal – between 120-200 milliseconds (msec)
What is a normal EGG? (Ventricular- QRS)
QRS complex
ventricular depolarisation.
Normal – less than 120 msec
What is a normal EGG? (Ventricular- ST)
ST segment – plateau phase.
Normal – at baseline
What is a normal EGG? (Ventricular- QT)
QT interval – total duration of ventricular depolarisation & repolarisation
What is a normal EGG? (Ventricular- R-R)
R-R interval – duration between ventricular depolarisations (heart beat)