Atrial Fibrillation & Flutter Flashcards
Is A.Fib a type of SVT or is it grouped with Atrial flutter?
Both A.Fib and flutter are types of SVT as they both originate over the purkinje-His bundle
Just for information:
Atrial dilatation for example due to Mitral stenosis or congestive HF as well as cardiac ischaemia (MI CAD) are causes of atrial fibrillation. Atrial dilatation affects its electric circuitry => causing Atrial remodeling => re-entry circuits
The management plan for A.fib is typically composed of 3 components: Rate control, rhythm control, and anticoagulation. In what scenario is one of the 3 components not pursued?
When there is permanent A.fib (prolonged >1 year + decision made to no longer pursue rhythm control), Rhythm control is stopped
What are the 4 types of A.fib?
Paroxysmal A.fib <7 days
Persistent A.fib >7 days
Long standing persistent >1 year
Permanent A.fib >1year + decision made to no longer pursue rhythm control
What % of those with paroxysmal A.fib will develop Persistent A.fib?
25%
Define Atrial fibrillation
Irregularly irregular arrhythmia characterised by rapid and irregular depolarisation of the cardiac atria
To bypass the last part, you can state the ECG findings of A.fib
List all the causes of atrial fibrillation
CCCHASE = 2 cardiac CHASE noncardiac
Cardiac causes: CC
C1: LA enlargement due to mitral stenosis or congestive HF
C2: Ischaemia => Previous MI/CAD
Non-cardiac causes:
Catecholamines: Epinephrine/NE released during sepsis, post-op, phaeochromocytoma, thyrotoxicosis/hyperthyroidism
Hypoxia: PE, pneumonia, COPD
Alcohol binge (Holiday heart syndrome) => Hypokalaemia + Hypomagnesia
Sympathomimetics: Cocaine, MDMA
Electrolytes: Hypokalameia/hyperkalaemia, Hypomagnesia
How would the cardiac causes of Atrial fibrillation lead to an arrhythmia?
honours => not in book
Atrial dilatation for example due to Mitral stenosis or congestive HF as well as cardiac ischaemia (MI CAD) are causes of atrial fibrillation. Atrial dilatation affects its electric circuitry => causing Atrial remodeling => re-entry circuits
What are the typical symptoms you would like to elicit in a hx of A.fib.
There is also extra information about what to ask in a hx if you wanna have a go at it too
Any arrhythmia:
Palpitations
Syncope/pre-syncope
SOB/Dyspnoea
Chest pain
Fatigue
! feeling of rapid neck pulsation !
+ Sxs of HF (+orthopnoea, PND, weight gain, swelling,)
+ Sx of Thromboembolic (neurological deficit for stroke, Abdo pain for mesenteric ischaemia, Leg pain for critical limb ischaemia and DVT, chest pain for PE)
Extra
+ RF of CAD (previous MI, surgery,
+ Thyroid, alcohol use…. Must ask about all RF
You are asked to perform an cardiac examination on a patient with atrial fibrillation. What findings are you looking for?
Dont forget heart failure (kinda all the findings lol)
Vitals: maybe tachypneic
General inspection: Typically asymptomatic, maybe SOB
Closer Inspection: Peripheral cyanosis, peripheral oedema, raised JVP
Palpation: Peripheral/sacral oedema, parasternal heave
Percussion: Pulmonary oedema is hyporesonant
Auscultation: Mitral stenosis (cause), tricuspid regurg for HF
List the RFs of Atrial fibrillation
From the causes:
Modifiable:
Smoking
Alcohol
HTN
Glycaemic control (or diabetes)
Hyperthyroidism
Non-modifiable:
Male
Age
Hx of CAD/MI
Family hx
Diabetes (or glycemic control)
!Rheumatic heart disease
What leads are best for assessing the P waves?
V1 + inferior leads (II, III, aVF)
What ECG findings are consistent with A.fib
Irregularly irregular
Tachycardia
No P waves (instead, fibrillating waves in leads V1, II, III, aVF
Narrow QRS <80ms or 0.08s
What investigations will you perform for A.fib? always with justification
As for any arrhythmia: except ECG
Bedside:
ECG/!Holter monitor: Looking for tachycardic, irregularly, irregular, absent P waves/fibrillating waves narrow QRS <80ms + screen for previous MI, BBB, or LV hypertrophy
Urine dipstick (sepsis)
Urinalysis (evidence of CKD to guide management between DOAC and Warfarin) + Toxicology (sympathetomimetics)
Bloods:
FBC - Anaemia, infection, low platelets if DIC, infection, sepsis)
CRP - raised in infl. + inf.
U&E - Hypomagnesia + hyper/hypokalaemia + medications
TFTs - hyperthyroidism
Troponin + CKMB (ischaemia as a cause or result of arrhythmia)
BNP - HF in severe arrhythmia
HbA1c and Lipid profile (RFs)
Imaging:
CXR - sx of HF (ABCDE)
ECHO - TTE - atrial/ventricular size (LA enlargement/LV hypertrophy), RV systolic pressure, valvular involvement, pericardial disease - TOE - LA (appendage) thrombus, Rule out vegetations in IE
Procedure: Exercise stress test - helps identify ischaemia
In the management of A.fib, what is meant by recent onset A.fib
A.fib sx <48 hours
How would you determine if A.fib is valvular or not?
TOE ECHO
How is long term anticoagulation in A.fib decided on?
CHADs VASC
Run me through the CHADs VASc score