1Stroke Prophylaxis Oral anticoagulation Lauren Butler Dr Pervez Muzaffar
2symptoms AF – most common arrhythmia Asymptomatic/exercise intolerance chest pain/palpitation/faintingCCF/TIAweight loss/diarrhoeaLight-headedness
3Diagnosis History Examination (inc manual pulse check) ECG (essential for diagnosis)Case specific bloodsEchocardiogramCxr
4Classification Timing and termination based classification 1st detected - only one diagnosed episodeParoxysmal - recurrent self terminates < 7 daysPersistent - recurrent lasts for > 7 daysPermanent - on-going long termOther categories:Lone AF – age under 60 no h/o CVD/HT/Pulmonary diseaseNon-valvular AF – absence of Rheumatic MVD/prosthetic valve or MV repairSecondary AF – MI/cardiac surgery/pericarditis/myocarditis/hyperthyroidism/PE/Pneumonia
5We need to improve Our prevalence of AF is below national average 1.12% BwD1.74% EnglandIn BwD we only anticoagulate 42% of High risk AF cases, England 56%, we should aim for 85%!
6Stroke in AF 14% of all strokes are due to AF AF increases risk of stroke five-foldstrokes per year occur in AF patients,of these are directly attributable to the AFAF strokes tend to be bigger and more disablingWarfarin reduces stroke risk by around 2/3
7Atrial fibrillation (AF) Points Pay stage AF1. The practice can produce a register of patients with atrial fibrillation5AF5. The percentage of patients with atrial fibrillation in whomstroke risk has been assessed using the CHADS2 riskstratification scoring system in the preceding 15 months(excluding those whose previous CHADS2 score is greater than 1)1040–90 %AF6. In those patients with atrial fibrillation in whom there is arecord of a CHADS2 score of 1(latest in the preceding 15months), the percentage of patients who are currently treatedwith anti-coagulation drug therapy or anti-platelet therapy650-90%AF7. In those patients with atrial fibrillation whose latest recordof a CHADS2 score is greater than 1, the percentage of patientswho are currently treated with anti-coagulation therapy40-70%
8Capturing information Grasp tool- how does it work?Works on all GP softwareSet of MIQUEST queries on AF patientsCalculates stroke risk using CHADS2With option to use latest CHA2DS2-VASc scoring toolHighlights those who would benefit from a medication reviewDoes not assess C/I to warfarinResults in spread sheet/dashboard format
11CHADS2 Score Congestive Heart failure 1 Hypertension 1 Age ≥ 75 1 DiabetesPrevious Stroke or TIAConsider anticoagulation if ≥ 2Use CHA2DS2VASc assessment tool if < 2
12Yet under prescribedNICE estimate that approximately 40% of patients in whom warfarin is indicated are not receiving it.RCPE % of people with AF should be considered for this treatment
13Aspirin vs. Warfarin Warfarin represents a 64% reduced stroke risk BAFTA - Warfarin did not increase haemorrhage risk in comparison with aspirin (Warfarin 1.4% Aspirin 1.6%)Falls - Older patients taking warfarin must fall about 295 times in one year for warfarin not to be optimal therapy and the propensity to fall is not a contraindication to the use of antithrombotic agents (especially warfarin) in elderly persons with AF.NB current guidance suggests that Aspirin should not be used for stroke prevention in AF. (RCPE UK 2012)
14CHA2DS2-VASc Score Congestive Heart Failure/ LVD 1 Hypertension 1 Age ≥ 75 yearsDiabetes mellitusStroke/TIA/TEVascular disease (MI, PAD or aortic plaque)Age between 65 and 74 yearSc - Sex category - FemaleScore of ≥ 2 anticoagulation therapyScore of 1 consider risk/benefit and HAS-BLED score to aid decision for anticoagulation or antiplatelet therapy
15HAS-BLED ScoreAnnual Hypertension, Uncontrolled Sys >160mmHg 1ptAbnormal Kidney (Cr > 200) and/or liver function 1pt eachStroke ptBleeding, previous history, anaemia or predisposition 1ptLabile INR, high INR or poor time in Therapeutic range 1ptElderly, age ≥ 65yrs 1ptDrugs and/or alcohol, antiplatelets, more than drinks per week pt eachA score of 3 or more is not a contraindication to oral anticoagulation but these patients require extra care
16CHADS 2 vs HAS – BLED Risk score Risk score 0 1.9%1 2.8%2 4.0%3 5.9%4 8.5%5 12.5%6 18.2%0 1.1%%%%%%
17Using both….. Lancashire & Cumbria Guidelines Calculate CHADS2 score ………CHADS2 > 1 anti-coagulateCHADS2 ≤ 1 calculate CHA2DS2-VASCCHA2DS2-VASC >1 anti-coagulateCHA2DS2-VASC ≤1no treatment (or aspirin)Consider a risk of bleeding assessment such as theHAS-BLED score before anticoagulation
18New oral anticoagulant drugs Dabigatran, RivaroXaban, ApiXabanDabigatrin (Pradaxa ) 150mg bd or 110 mg bdRivaroxaban (Xarelto ) 20mg odApixaban 5mg bd (not yet licensed for stroke prevention in AF)NOACs are recommended as an treatment option where warfarin is either contraindicated or where the patient has a documented hypersensitivity to or intolerance of coumarin anticoagulants severe enough to cause treatment withdrawalStudies show similar or better efficacy than warfarin with less risk of bleedingNo monitoring requiredFew drug and diet interactionsVery expensive (but savings on monitoring)
19New oral anticoagulant drugs (2) Still black triangle drugs – Amber rating in BwDNo simple antidote (but short half life)In RE-LY trial, Dabigatran higher drop out rate than warfarinHigher rate of GI bleeding, lower rate of ICHWarfarin is still likely to remain drug of choice for those who are well controlled (TTR 65%)However NOACs do have advantages, and will benefit a proportion of the population
20Warfarin or NOAC ? Where to refer ? Warfarin Anticoag clinicNOAC Community cardiology (Mammen)Remember – NOACs still carry bleeding risk, black triangle drugs with no antidote
21Key points Aspirin is ineffective in stroke prevention for AF If warfarin can not be controlled and compliance is not the issue then a NOAC should be commencedWhere compliance is the issue, then is it preferable to at least be able to monitor this?Watch NOACs in the elderly and those with poor renal functionRemember – BwD anticoag service has domiciliary service for patients unable to attend clinic
22case66 years old female presented with sob/tiredness feels skipping beat occasionally when playing golfno cough no chest pain no fainting no other symptomsPMH: nilNo allergy
23Examination/testsBP 132/70 pulse 104/min irregular no murmur no ankle oedema no carotid bruits CNS- normal Chest- sats 98% RR 20/min no wheeze mild basal crepts apyrexial ECG AF 112/min Requested bloods
25Anticoagulate?CHA2DS2-VASc Score ??What is next?
26NOACAfter discussion she decides to be referred to anticoagulation clinicShe comes back in a week time with her consultant surgeon son who says he does not want her to go on warfarin – but like her to go on Dabigatran (NOAC)Your response to his request?He wishes to pay for private prescription?