CARDIOVASCULAR JOURNAL OF AFRICA • Vol 21, No 4, July/August 2010
194
AFRICA
thrombi being cardio-embolic, originating mostly from the left
atrial appendage.
8
Despite abundant information from ongoing
clinical trials in favour of warfarin use in patients with chronic
atrial fibrillation to prevent stroke, it remains a concern how
to approach patients in order to implement the anticoagulation
strategy in everyday clinical practice. The prescription rate of
anticoagulation therapy for eligible atrial fibrillation patients is
only 15 to 44%.
9
Under-utilisation of anticoagulation therapy is due to either
physician or patient reluctance. Factors contributing to physician
under-prescription rates of warfarin therapy are mostly overesti-
mation of the associated risks of warfarin therapy,
10
or underesti-
mation of the stroke risk.
11
An important factor in patient reluctance, contributing to
under-usage of anticoagulation therapy for chronic atrial fibril-
lation, was the lack awareness of thrombo-prophylaxis for this
condition.
12
Studies have shown that very few elderly patients with
chronic atrial fibrillation realised the risk–benefit ratio of anti-
coagulation treatment.
13
These data coincide with our findings,
where 68.57% of patients with atrial fibrillation at moderate to
high risk of stroke had no information concerning the importance
of anticoagulation therapy. Even if the patient is well informed
by the physician about the benefits of warfarin for their condi-
tion, they may still refuse to take the medication due to the diffi-
culties of INR monitoring or adjustment to the dietary lifestyle.
14
Pictograms have been shown to be a useful way of repre-
senting the risk–benefit ratio of warfarin for atrial fibrillation,
thereby making the importance of anticoagulation treatment
more understandable to patients.
13
However, studies have demon-
strated that providing additional information on warfarin use,
such as the need for regular INR monitoring or abstinence from
alcohol had a negative effect on the patient’s decision to opt for
anticoagulation therapy.
15
The large proportion of uneducated older people in Kosova,
particularly women, presents a problem for physicians prescrib-
ing anticoagulation therapy for patients with chronic atrial
fibrillation. This makes it challenging to explain to their patients
the risk–benefit ratio of warfarin usage in numerical terms.
Therefore, we hypothesised that by creating visual images of
their condition, patients would agree to start on anticoagulation
treatment.
After the TEE procedure, the images were carefully explained
to the patient and an accompanying person. The presence of
thrombus was described as a potential cause of ischaemic
stroke or other thrombo-embolic event, SEC was explained as
a precursor of thrombus, and enlargement of the atria or atrial
appendages was represented as a favourable condition for future
thrombus formation.
This method proved to be effective in achieving a 75.71% rate
of adherence to warfarin therapy and 100% to thromboprophy-
laxis with either warfarin or aspirin in our study population over
a two-year follow-up period. We believe that our results demon-
strate the importance of routine clinical use of TEE in patients
with chronic non-valvular atrial fibrillation, as a tool to convince
these patients of the need for anticoagulation treatment.
One limitation of this study was that a control group was not
formed. Another was that a relatively small number of patients
were included in the study.
Conclusion
TEE is a valuable method not only to asses the presence of
thrombi in the atrial appendage or SEC in patients with chronic
atrial fibrillation, but is also a handy visual means of persuading
patients to commence anticoagulation treatment.
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