Cardiology Flashcards
Ionotropes cause ….
Chronotropes cause….
Increased strength of heart
Increased rate of heart
Alpha 1 receptors are highest in
Beta 1 receptors are highest in
Beta 2 receptors are highest in
Vascular smooth muscle and cause vasoconstriction
Cardiac muscle and cause increased rate and contractility
Vascular smooth muscle and cause vasodilation
TRUE SINUS RHYTHM
P wave is positive in lead II and negative in AvR
Branch blocks can be separated into:
Incomplete -
Complete -
Incomplete are delay PR interval, 1st degree heart block, and dropped beats, Mobitz 1, Mobitz 2 and high grade.
Complete is 3rd degree heart block.
Left axis deviation is present when -
It is caused by -
LAD is when positive QRS in Lead I and negative QRS in lead aVF.
Can be a normal variant, left anterior fasicular block and rarely LVH.
Right axis deviation is -
Caused by -
RAD is when negative QRS in lead I and positive QRS in lead aVF.
Caused by normal variant, RBBB or RVH.
Mobitz TI
Mobitz TII
3rd degree
PR interval prolongs from beat to beat then one beat is not transmitted.
PR interval constant, occasional non-transmitted beat 2:1 or 3:1, look a how many p waves for QRS.
Very broad QRS and slow HR.
RBBB
LBBB
M in v1 and W in v6
Always pathological ! Wide complexes with negative or W in v1 and M patten in v4-v6, t wave inversion in the anterolateral leads.
Wolff Parkinson White
On ECG shows:
Is caused by:
Short PR interval and Slurred QRS interval (delta wave)
Extra or accessory conducting bundle between atrium and ventricle. Left sided, reaches ventricle early and pre-excitation occurs. Can cause paroxysmal tachycardia.
S1 is
S2 is
S3 can be
S4 can be
S1 is the Mitral and Tricuspid valve closing
S2 is the Aortic and pulmonary valves closing
S3 is not a valve but new HF or volume overload
S4 stiff ventricles.
Ejection systolic murmurs indicate….
Other signs you can look for before listening to the heart are…
Caused by…
Manage with…
Aortic stenosis
Narrow pulse pressure, slow rising pulse, displaced apex beat, systolic thrill. Tall QRS on ECG (LAD)
Calcification (commonest cause), Bicuspid aortic valve (young), Infection (RF and infective endocarditis).
TAVI, valve replacement, conservative.
Pan systolic murmur indicates….
Other signs before stethoscope….
Caused by….
Manage with….
Mitral regurgitation (radiates left to the axilla loudest on expiration)
Possible A. Fib. Left displacement of apex beat, parasternal heave.
Degenerative (LV dilatation), Ischaemia (post MI) and infections.
Mitral repair surgery, valve replacement surgery, conservative manage HF symptoms.
Antiplatelets
Aspirin action:
Clopidogrel action:
Aspirin acetylates cox preventing the production of THROMBOXANE A2 inhibiting platelet aggregation.
Clopidogrel is an ADP receptor antagonist which also blocks platelet aggregation.
Anticoagulants
Warfarin action
Apixaban
Dabigatran
LMWH
Warfarin acts on Vitamin K preventing its metabolism and action on factors 2,7,9,10.
Apixaban is an Xa inhibitor with lower risk: benefit than warfarin.
Dabigatran is a direct thrombin inhibitor lower risk: benefit ratio to w.
Low molecular weight heparin is used in Acute Coronary Syndrome.
Beta blockers
Block B1:
Block B2:
B1 : negative into inotrope and chronotrope so reduces pulse.
Selective Bisoprolol.
B2 : induce peripheral vasoconstriction and bronchoconstriction. Propranolol (non-selective).
