cardiovascular disorders Flashcards
what is heart failure
the heart is unable to maintain adequate circulation for metabolic requirements of body
what is decreased systolic function
reduced ejection fraction
EF > or equal to 40% = decreased systolic function
weakened heart muscle - left ventricle
less able to pump
what is decreased diastolic function
preserved ejection fraction
EF > or equal to 50% decreased diastolic function
diastolic heart failure
smaller area for blood in left ventricle but still gets pumped out
underlying causes for heart failure
secondary to cardiac damage
ischaemia, myopathy, hypertension, valve disease
signs and symptoms for heart failure
exertional dyspnoea
tests for heart failure
blood test
elevated brain natriuretic peptide (BNP) and chest X ray - cardiomegaly
treatments for heart failure
drugs reducing exertional pressure on heart
what does an enlarged QRS complex show
heart failure
due to increased muscle mass on heart > increased electrical current
what is atrial fibrillation
disorganised electric activity and contraction
uncoordinated activity
absence of p wave caused from electrical stimulation from SAN to AV node
what is Wolff-Parkinson-White (WPW)
syndrome causing tachycardia and abnormal cardiac electrical conductance accessory pathway (most common in left ventricle) causes pre-excitation of QRS
what are underlying causes for atrial fibrillation
spontaneously active cells throughout the atria - uncoordinated pacemaker currents in the atria
what are underlying causes for WPW
additional accessory conduction pathway (the bundle of Kent) between the atria and the ventricles
what are some signs and symptoms for atrial arrythmias
paliptations and chest pain
absent p waves and irregularly irregular rhythm shows..
atrial fibrillation
what does QRS pre excitation and biphasic/inverted T wave on ECG show
Wolff-Parkison-white
what are some treatment options for atrial fibrillation
strategies to maintain sinus rhythm (eg cardioversion, anti-arrhythmics, catheter ablation)
what are some treatment options for WPW
benign - no treatment required
what is 1st degree block
slowing down of conduction through AV node (blockage at AV node) due to current slowing down AV node
what is 2nd degree block
reduced transmission of signal from atria to ventricles
what is 3rd degree block
complete block of current from atria to ventricles
what are the underlying causes for conduction block
damage (fibrosis, calcification, necrosis) to the conduction system (AV node of His purkinje system)
what does increased PR interval on ECG show
1st degree block
what does increased PR interval or missing QRS complexes
2nd degree block
what do p waves not followed by QRS complexes show
3rd degree block
what are treatments for conduction block
discontinuation of AV blocking drugs (eg beta blockers, calcium channel blockers)
or pacemaker implantation in severe cases
what is hypertension
clinical BP > or equal to 140/90 mmHg and ambulatory BP daytime average > or equal to 135/88 mmHg for prolonged period
what are the underlying primary and secondary causes of hypertension
primary - unknown
secondary - resulting from another medical condition (kidney disease, adrenal disease)
what are some treatments for hypertension
lifestyle changes followed by anti hypertensive medication
what are some acute coronary syndromes
angina
non ST elevated myocardial infarction (NSTEMI)
ST elevated myocardial infarction (STEMI)
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 caused by atherosclerosis and artery blockage - small occlusion of coronary artery
what is a STEMI
ST elevated myocardial infarction
serious myocardial tissue damage due to prolonged ischaemia caused by severe atherosclerosis and complete artery blockage/occlusion
what are underlying causes for angina
atherosclerotic lesions of the coronary artery causing ischaemia
what are underlying causes for NSTEMI
artery blockage
what are underlying causes for STEMI
complete artery blockage
what does an ST depression/no changes and high troponin levels indicate
NSTEMI
what does ST elevation with reciprocal ST depression and high troponin levels indicate
STEMI
what are treatments for angina
vasodilators
what are treatments for NSTEMI
coronary stents antiplatelets vasodilators antiemetics oxygen and pain relief
what are some treatments for STEMI
coronary stents antiplatelets vasodilators antiemetics oxygen and pain relief
how can you show one heartbeat/interval/HR on an ECG
from one point to another eg RR interval
what does hypertrophy of the left ventricle show up as on an ECG
larger QRS complex
larger ventricle = larger electrical signal
what is most likely caused by angiotensin 2 (potent vasoconstrictor)
increased afterload resulting from the impaired ventricular function in heart failure is most likely caused by angiotensin 2
afterload is determined by blood pressure
increased blood pressure = increased afterload
what also causes vasoconstriction but is less potent than angiotensin 2
noradrenaline
can pregnant women use ACEs
NO
if an accessory pathway was found in the right atrium and ventricle instead of the left atrium and ventricle for WPW would the ECG traces be the same
yeees
what does AV block prolong
the PR interval
what does no QRS indicate
2nd degree heart block
what wave shows ventricular repolarisation/relaxation
T wave
