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for major bleeding. A bleeding risk
score, HAS-BLED, has been recently
developed.27 The HAS-BLED can
be used to assess bleeding risk in
patients with AF (Table 5). A score of
≥3 indicates high risk, and caution is
needed if antithrombotic therapy is
commenced.27 Absolute and relative
contraindications to warfarin are shown
in Table 6.28 The European Guidelines
for the management of atrial fibrillation
state that the 'fear of falls may be
overstated, as a patient may need to
fall ~300 times per year for the risk of
intracranial haemorrhage to outweigh
the benefit of oral anticoagulation in
stroke prevention'.27 The NPS has issued
advice that the propensity to fall does
not preclude warfarin unless it poses a
higher risk of bleeding for an individual.29
It was decided that warfarin initiation
was risky in Mr ML -- the GP indicated
that although Mr ML denied any
alcohol use, the community nurses
had informed him that Mr ML often
had empty bottles of bourbon (Mr ML's
HAS-BLED score = 3: 1 point for
suspected alcohol abuse, 1 point
for anaemia, and 1 point for elderly;
if aspirin was continued then his HAS-
BLED score = 4). His risk is arguably
higher because of his renal impairment
(creatinine clearance ~30 mL/min), but
strictly according to the algorithm his
creatinine level should be >200 μmol/L).
The community nurses were only able
to visit Mr ML three times a week
and Mr ML did not have any family
or reliable friends who could assist in
managing warfarin dosing.
Consideration should be given to
reducing the amiodarone dose to 100
mg daily. Amiodarone is frequently used
as maintenance therapy after reversion
to sinus rhythm.30 The maintenance
treatment for amiodarone is usually
between 100--400 mg per day.31 Elderly
patients and those with little body fat
(e.g. Mr ML) can be treated with a very
low dose (100 mg/day) although there
is no clinical trial data to support this
reduced dose strategy.32 If the dose of
amiodarone is changed, it is important
to closely monitor the patient as it
has a long half-life of 22--107 days and
inhibits cytochrome P450 2C9 and 2D6.
The maximum effect of dose changes
is not seen for 1--3 months or more.
This is relevant to Mr ML as he is
using metoprolol and therefore a dose
reduction in metoprolol may be required
if amiodarone dose is reduced.31
Dose reduction in
A reduction in the dose of atorvastatin
from 40 mg to 20 mg daily is warranted
in view of his well-controlled lipids.
In addition, given his age, history of
hypothyroidism and renal failure, and
use of amiodarone, Mr ML is at greater
risk for statin-induced myopathy.32
Outcomes at seven
months post HMR
• Re-commencement of medications
(no further admissions to hospital).
• Ongoing community nursing
care (three times a week) which
delivers medicines from community
pharmacy in a WebsterPak.
• Amiodarone dose reduced to
100 mg daily following cardiologist
consultation (dose of metoprolol
• Atorvastatin reduced to 20 mg daily.
• Iron supplement commenced.
• Leg wound healed.
European Heart Rhythm Association;
European Association for Cardio-
Thoracic Surgery. Guidelines for the
management of atrial fibrillation: the
Task Force for the Management of
Atrial Fibrillation of the European
Society of Cardiology (ESC). Eur Heart
J. 2010 Oct; 31(19):2369--429.
1. Stewart S, Pearson S. Uncovering a multitude of
sins: medication management in the home post acute
hospitalisation among the chronically ill. Aust N Z J
Med. 1999 Apr; 29(2):220--7.
2. Thomsen LA, Winterstein AG, Sondergaard B, et al.
Systematic review of the incidence and characteristics
of preventable adverse drug events in ambulatory care.
Ann Pharmacother. 2007; 41:1411--26.
3. van Walraven C, Seth R, Austin PC, et al. Effect of
discharge summary availability during post-discharge
visits on hospital readmission. J Gen Intern Med. 2002;
4. Bolton P, Mira M, Kennedy P, et al. The quality of
communication between hospitals and general
practitioners: an assessment. J Qual Clin Pract. 1998;
5. Middleton S, Appleberg M, Girgis S, et al. Effective
discharge policy: are we getting there? Aust Health
Rev. 2004; 28:255--9.
6. Roughead EE, Kalisch LM, Ramsay EN, et al. Continuity
of care: when do patients visit community healthcare
Table 4. Approach to thromboprophylaxis in patients with AF
using CHA2DS2-VAsc score (adapted from reference 27)
VAsc score Recommended therapy
One 'major' risk factor or >2
'clinically relevant non-major'
One 'clinically relevant non-
major' risk factor
Either OAC+ or aspirin
75--325 mg daily.
Preferred: OAC rather than aspirin.
No risk factors
Either aspirin 75--325 mg daily or no
antithrombotic therapy. Preferred:
no antithrombotic therapy rather
+OAC, such as a VKA, adjusted to an intensity range of INR 2.0--3.0. New OAC drugs, which may be viable alternatives
to a VKA, may ultimately be considered. Suggestions for thromboprophylaxis using dabigatran considering stroke and
bleeding risk stratification:
a) Where oral anticoagulation is appropriate therapy, dabigatran may be considered as an alternative to adjusted
dose VKA therapy.
i) If a patient is at low risk of bleeding (i.e. HAS-BLED score of 0--2; see Table 6 for HAS-BLED score definition),
dabigatran 150 mg twice daily may be considered, in view of the improved efficacy in the prevention of stroke
and systemic embolism (but lower rates of intracranial haemorrhage and similar rates of major bleeding events,
when compared with warfarin).
ii) If a patient has a measurable risk of bleeding (e.g. HAS-BLED score of ≥3), dabigatran etexilate 110 mg twice
daily may be considered, in view of a similar efficacy in the prevention of stroke and systemic embolism (but
lower rates of intracranial haemorrhage and of major bleeding compared with VKA).
b) In patients with one 'clinically relevant non-major' stroke risk factor, dabigatran 110 mg twice daily may be
considered, in view of a similar efficacy with VKA in the prevention of stroke and systemic embolism but lower
rates of intracranial haemorrhage and major bleeding compared with the VKA and (probably) aspirin.
c) Patients with no stroke risk factors (i.e. CHA2DS2-VAsc = 0) are clearly at such low risk, either aspirin 75--325 mg
daily or no antithrombotic therapy is recommended. Where possible, no antithrombotic therapy should be
considered for such patients, rather than aspirin, given the limited data on the benefits of aspirin in this patient
group (i.e. lone AF) and the potential for adverse effects, especially bleeding.
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