Post on 26-Dec-2015
transcript
BackgroundBackgroundMost common sustained cardiac
arrhythmiaPrevalence 0.5-1% in general
populationIt is characterised by an ECG:-
◦Lacking any consistent p waves◦Irregular ventricular rate
ClassificationClassification1. 1st detected vs.. Recurrent2. Self terminating vs.. Not self terminating3. Symptomatic vs... Asymptomatic4. Paroxysmal (self terminating within 7
days)5. Persistent (if cardioverted to SR by any
means or last >7 days regardless of how it terminates)
6. Permanent (does not terminate or relapses within 24 hrs of cardioversion)
7. Lone (in the absence of structural heart disease) vs... Idiopathic (in the absence of any disease)
Common CausesCommon CausesHypertensionLeft Ventricular FailureCoronary Artery DiseaseMitral/Tricuspid Valve DiseaseHOCM
SymptomsSymptomsPalpitationsDyspnoeaFatigueSyncopeChest Pain30% present with AF as
incidental finding
SignsSignsIrregular Pulse
◦Faster at apex than at wristVariable intensity of 1st HSAbsent “a” wave in the JVP
InvestigationsInvestigationsECGCXRBloods
◦FBC, UE, Cardiac Enzymes, TFT, LFT◦Mg, Ca2+
Echo24 hr tape/ETT/Angiogram
ManagementManagementMake a diagnosisDecide on rate or rhythm control
strategyStratify stroke risk and consider
thromboprophylaxis
Rate controlRate controlRate control first if:-
◦over 65 ◦with CHD (the vast majority)
Medication options:-◦Beta-blocker or Calcium Antagonist
(Verapamil/Diltiazem)◦If still no better then add in Digoxin
Rhythm controlRhythm controlRefer for rhythm control
(cardioversion) if:-◦Symptomatic with congestive heart
failure◦Younger◦Unable to achieve adequate
Bleeding risk with Bleeding risk with WarfarinWarfarinOver 75NSAIDsPast Hx of bleedingPolypharmacyUncontrolled BPOn other antiplatelets
Stroke risk stratification and Stroke risk stratification and thromboprophylaxisthromboprophylaxisLow
◦ Under 65 and no risk factor◦ Aspirin if no contraindications
Moderate◦ Over 65 and no risk factors◦ Under 75 with risk factors◦ Aspirin vs. Warfarin
High◦ Previous ischaemic event/TIA◦ Over 75 with risk factors; valve disease or
heart failure◦ Warfarin if no contraindications
Annual Risk of StrokeAnnual Risk of StrokeRisk Group No Rx Aspirin Warfarin
Very High (prev CVA/TIA)
12% 10% 5%
High 5-8% 4-6% 2-3%
Moderate 3-5% 2-4% 1-2%
Low 1.2% 1% 0.5%
CHADSCHADS22
Condition Points
C Congestive Heart Failure 1
H BP more than 160mmHgOr Treated BP
1
A Age > 75 1
D Diabetes 1
S2 Prior stroke/TIA 2
CHADSCHADS22
Score
Annual Stroke Risk %
Risk Therapy Range
0 1.9% Low Aspirin 75- 300 mg
1 2.8% Moderate Aspirin/Warfarin
2/> 4.0% > High Warfarin INR 2-3
Paroxysmal AFParoxysmal AFThromboprophylaxis
◦Just the sameRhythm drugs
◦Standard B Blocker vs.. Pill in Pocket◦Sotolol vs.. Class 1c agents◦Amiodarone◦Referral to EPS specialist
Atrial FlutterAtrial FlutterSame antithrombotic Rx as AFRe-establish SR
◦Cardiovert (Medication/DCCV)◦Pacing
PapersPapersMixed comparison of stroke
prevention treatments in patients with non-rheumatic AF – Arch Int Med 2006:166:1269◦Warfarin more effective than Aspirin
in reducing stroke in AF◦Warfarin: will prevent 28 strokes at
the cost of 11 major bleeds◦Aspirin: will prevent 16 strokes at the
cost of 6 major bleeds
PapersPapersComparison of Warfarin vs.
Aspirin-Clopidogrel in AF Lancet 2006:367:1903◦Warfarin is superior to dual
antiplatelet therapy
PapersPapersBAFTA study 2007: Warfarin vs.
Aspirin in an elderly, community population. Lancet 2007:370:493◦Support the use of Warfarin over
Aspirin in patients over 75 unless there are contraindications
PapersPapersACTIVE A Trial NEJM 2009;360:2066
◦Neither regime as effective as Warfarin Warfarin 1.1-1.3% Aspirin 3.3% Aspirin + Clopidogrel 2.4%
◦Conclusion: In patients with moderate to high risk of stroke in whom Warfarin is unsuitable, the combination of Clopidogrel + Aspirin will be most likely to provide NET clinical benefit
PapersPapersThe ATHENA Study. NEJM
2009:360:668◦Primary outcome occured in 32% of
the Dranadone group vs. 39% of the placebo (ARR of 7% = NNT 14)
◦Significant reduction in CV deaths (2.7% vs. 3.9%)
PapersPapersAspirin + Warfarin in patients
with AF and vascular disease BMJ2008:336:614◦If a patient taking Aspirin for a CVA
develops AF stop Aspirin start Warfarin