Laz Cardio Flashcards
what valve connects the RA to the RV
TRICUSPID
What valve connects LA to LV
MITRAL
Explain pathway of deoxy blood from systemic circulation
systemic circulation > RA > Tricuspid > RV > Pulm artery > lungs
explain pathway of oxy blood from lungs
lungs > LA > Mitral > LV > Aorta > systemic circulation
what is the formula for EF
EF = stroke volume / end diastolic volume
explain in your own words what EF measures
how much of the blood in the ventricle at the end of diastole is squeezed out during ventricular contraction
what is normal EF
ABOVE 50%
What are the two types of HF and what are their expected EFs
preserved EF: EF>50
reduced EF: EF<40
explain HFpEF
inadequate filling of the ventricle but normal ventricular contraction
the ventricle contracts normally but is too stiff to fill sufficiently
explain causes of HFpEF
anything that causes stiffening of the ventricle and prevents it from distending appropriately
- REDUCED DISTENSIBILITY e.g. constrictive pericarditis
- PRESSURE OVERLAOD e.g. HTN
- volume overload e.g valve regurg
Explain causes of HFrEF
outflow obstruction OR impaired contractility
e.g. MI, cardiomyopathy, arrythmia
what are key ix for suspected HF
Bedside: ECG (ischaemia?)
Bloods: ABG (LHF > pulm oedema), Trops (ischaemia), BNP
Imaging: CXR (pulm oedema), Echo (EF?)
what is the definition of AF
rapid chaotic ineffective atrial electrical conduction, with electical impulses being generated abnormally
what is AF on an ECG
irreg irreg rhythm with absent P waves
What does AF management depend on ? i.e. explain what underlies the choice of rate vs rhytm control
how likely is the patient to maintain sinus rhythm after cardioversion? i.e. if AF is permanent / no identifiable cause, it is unlikely that cardioverting them will help
what is the first thing you need to look at in a pt with AF when deciding what type of management is appropriatew?
if haemodynamically stable / unstable
if unstable, immediate cardioversion
What are the two key types of antithrombotics
anticoagulants
antiplatelets
what kinds of clots do you use anticoagulants for and why
for risk of clotting due to STASIS
usually VENOUS
because when blood is static (e.g. immobility in the deep veins of the legs or in the atria) the coag factors bounce off each other and are likely to cause a clot
give examples of anticoagulants
warfarin
antiXa or antiIIa e.g. rivaroxaban
what kinds of clots do you use antiplatelets for and why
for risk of clotting due to VESSEL WALL INJURY
usually ARTERIAL e.g. in atherosclerosis
vessel is damaged > subendothelial prothrombotic agents exposed > platelets aggregate > arterial clot
how do you manage an SVT
if haemodynamically unstable > DC cardiovert
If stable: vagal maneuvres >adenosine 6mg > adenosine 12mg > adenosine 12mg > seek specialist advice
whom must you not give adenosine to for SVT?why
asthmatics
because it can cause bronchoconstriction
give verapamil instead
what are the three classes of anticoagulants \
heparins
DOACs
Vit K antagonist (warfarin)
what are the two types of heparin and how are they administered
LMWH - SC
unfractionated heparin - SC/IV
what is LMWH used for
VTE treatment or prophylaxis
what is a disadvantage of LMWH
reduces renal function > so dont use if significant renal impairment
give an example of LMWH
enoxaparin
what are advantages of unfractionated heparin
- do not affect renal function> can be used if renally impaired
- rapid onset of action and rapid reversal
what are disadvantages of unfractionated heparin
risk of HIT
APTT moniroting
What is an advantage and disadvantage of doac?
advantage: no monitoring required, oral
disadvantage: not good in pts with poor renal function
What is warfarin still used for
AF + moderate or severe MS (as high stroke risk)
mechanical valve
what are disadvantages of warfarin
repeated INR monitoring
drug interactions
what classifies JVP as being elevated
JVP is elevated if the vertical distance between the sternal angle and the highest point of the pulse is greater than 4cm.
how do you elicit the JVP and what does that do?
How to Elicit: press over the right upper quadrant for 10-15 seconds while inspecting the JVP.
Significance: The reflex temporarily increases venous return to the right atrium, making the jugular venous pulsation more pronounced.
causes of raised JVP
Fluid overload - excessive IV fluids, renal disease, heart failure
Right ventricular systolic failure - cor pulmonale, left ventricular failure
Right ventricular diastolic failure - constrictive pericarditis, tamponade
Pulmonary hypertension
what do you do with AF if patient is ACUTELY UNSTABLE, but they have had AF for >48h?
TOE to check for thrombi
then DC cardiovert immediately
what causes pulsus alternans, and why=?
severe LV dysfunction causes PULSUS ALTERNANS (1 strong and 1 weak beat)
due to compromised ventricular filling
what drug causes very good long term benefit in mild-mod HF
CARVEDILOL (beta blocker)
what drug causes benefit in severe HF
spironolactone
why does HF cause syncope or eventually death????
Due to ARRHYTMIAS (rhythm disturbances)
how does pulmonary HTN present on exam on palpation
LEFT PARASTERNAL HEAVE (of right ventricle)
what is normal but may look abnormal on ECG
T wave inversion in V1
what comes up on ECG in a paced rrhytm
RSR pattern in V6
what is the technical term for fast AF
AF with rapid ventricular respone
what is the rate in fast AF
> 100
What are causes of fast AAF
infection
dehydration
electrolyte imbalance
what is the rate in slow AF
<60
what are causes of slow AF
hypothermia
digoxin toxicity
meds
