CV Disorders Flashcards
What is Atrial fibrillation (AF)?
Disorganised electric activity and contraction
What is Wolff-Parkinson-White (WPW)?
Syndrome causing tachycardia & abnormal cardiac electrical conductance
What are 2 forms of atrial arrhythmias?
Atrial fibrillation
Wolff-Parkinson-White
What is an underlying cause of AF?
Spontaneously active cells throughout the atria
What is an underlying cause of WPW?
additional accessory conduction pathway (the bundle of Kent) between the atria and ventricles
What are signs + symptoms of AF + WPW?
Palpitations & chest pain
What are ECG findings for AF?
Absent p-waves & ‘irregularly irregular’ rhythm.
What are ECG findings for WPW?
QRS pre-excitation & biphasic/ inverted T-wave of ECG
What are treatment options for AF?
strategies to maintain sinus (e.g. cardioversion, anti-arrhythmics, catheter ablation)
What are treatment options for WPW?
benign, no treatment required
What is conduction block?
b
What are underlying causes of conduction block?
Damage (fibrosis, calcification, necrosis) to the conduction system (
AV node or His Purkinje system)
How are conduction blocks graded?
First-degree block
Second-degree block
Third-degree block
What is first-degree block?
slowing down of conduction through AV node
What is second-degree block?
reduced transmission of signal from atria to ventricles
What is third-degree block?
complete block of current from atria to ventricles
What are the ECG finding for a first-degree block?
increased P-R interval
What are the ECG finding for a second-degree block?
increased P-R interval or ‘missing’ QRS complexes, depending on type of block
What are the ECG finding for a third-degree block?
p-waves not followed by QRS complexes
What are the treatment options for conduction block?
Discontinuation of AV-blocking drugs (e.g. beta-blockers, calcium channel blockers)
pacemaker implantation in severe cases
What is heart failure?
Heart unable to maintain adequate circulation for metabolic requirements of body
What is preserved ejection fraction (HFpEF)?
EF ≥ 50%, ↓ diastolic function, stiff heart muscle
What is reduced ejection fraction (HFrEF)?
EF ≥ 40%, ↓ systolic function, weakened heart muscle
What is an underlying cause of heart failure?
secondary to cardiac damage (ischaemia, myopathy)
hypertension
valve disease
What are signs + symptoms of heart failure?
exertional dyspnoea (shortness of breath during exertion)
What are tests that can be done to identify heart failure?
Blood test: elevated brain natriuretic peptide (BNP)
Chest X-ray: cardiomegaly
What are the treatment options for heart failure?
Drugs that reduce the exertional pressure on the heart
What is hypertension?
high blood pressure
How is hypertension defined clinically?
Clinical BP ≥ 140/90 mmHg & ambulatory BP daytime average ≥ 135/85 mmHg
What are the causes of primary hypertension?
unknown
What are the causes of secondary hypertension?
resulting from another medical condition (e.g. kidney disease, adrenal disease)
How can hypertension be identified?
Blood pressure measurement: readings ≥ 135/85 mmHg
What are treatment options for hypertension?
Lifestyle changes followed by anti-hypertensive medication
What is angina?
chest pain (due to myocardial ischaemia caused by atherosclerosis)
What is NSTEMI?
non-ST-elevated myocardial infarction : myocardial tissue damage due to prolonged ischaemia
What is STEMI?
ST-elevated myocardial infarction : serious myocardial tissue damage due to prolonged ischaemia
What is the underlying cause of angina in acute coronary syndromes?
Atherosclerotic lesions of the coronary artery
What is the underlying cause of NSTEMI?
atherosclerosis + artery blockage
What is the underlying cause of STEMI?
severe atherosclerosis + complete artery blockage
What are signs + symptoms of angina?
chest pain on exertion (stable) or at rest (unstable)
What are signs + symptoms of NSTEMI?
chest pain, sweating, nausea + vomiting
What are signs + symptoms of STEMI?
radiating chest pain, sweating, nausea & vomiting
What would be the ECG findings for NSTEMI?
ST-depression/no changes
What would be the ECG findings for STEMI?
ST-elevation w/ reciprocal ST-depression
What would the blood test findings for NSTEMI + STEMI?
high troponin levels
What are the treatment options for angina?
vasodilators
What are the treatment options for NSTEMI + STEMI?
coronary stents antiplatelets vasodilators anti-emetics oxygen & pain-relief
What does WPW result in pre-excitation before QRS complex?
additional ventricular pathway = ventricular depolarisation before ventricular depolarisation starts in the AV node
Why does WPW result in a biphasic T-wave?
due to current not being stopped at AVN, another repolarisation is starting before the depolarisation ends
