Diagnostic measure of atrial fibrillation on patients at outpatient TIA-clinic

Atrial fibrillation (AF) predomintly occurs at later age and is associated with
a higher chance of cardioembolic stroke or Transient Ischemic Attack (TIA).
Each year, more than 45.000 people have a stroke or TIA in the Netherlands.
Twenty-four percent of patients with ischaemic stroke (CVA or TIA ) have atrial
fibrillation. A stroke can have serious consequences for the patient and his
environment. Within this group of patients, twenty-five percent die within one
month of the attack. This occurs frequently due to a cardiovascular disorder.
Nineteen percent of all patients who have a stroke experience severe
constraints in their daily activity.

The expectation is the prevelation of AF will increase the following years,
due to the (double) aggiing of the population, and more patients survive a
former fatal heartdisease. This last group of patients often develops
complications like AF.

AF can present permanent (persistent or permanent atrial fibrillation) or
present in episodes (paroxysmal atrial fibrillation). There is no difference in
risk of an ischaemic stroke between the several types of atrial fibrillation.
AF leads to an irregular heartbeat that often is under diagnosed. AF can only
be diagnosed at the time of appearance by registration of the heartrythm via an
electrocardiography (ECG) or holterregistration. Paroxysmal atrial fibrillation
is therefore often missed and underdiagnosed.

According to the current guidelines (CHADS2-score) patients with stroke or TIA
recieve vitamin-K-antagonists (such as acenocoumarol). If the diagnose AF is
missed, this group of patients will have an increased chance of a relapse
stroke or TIA. The ischaemic attack in patients with AF is in generally more
severe than patients without AF. This is probably because of the size of the
embolism of the left atrial. This underlines the importance of diagnostic
measure of AF.

Recent analysis of the practice and literature have identified that long term
registration of heartrythm is essential in diagnostic measure of paroxysmal
atrial fibrillation. In patients with stroke or TIA ánd AF, left ventricle
hypertrophy, left atrial enlargement, premature atrial heartbeats with a
frequency of greater than 70 beats per minute is diagnosed. Beside that, AF
occurs in patients with stroke or TIA and with cerebral ischemia in several
flow areas, with hyperthyroid and in patients with signs and symptoms fitting
with AF like palpitations, short of breath, dizziness and chest pain.

(see also page 3 and 4 of the study-protocol)

The objective of this study is to optimize the diagnostic strategy of atrial
fibrillation in patients with stroke or TIA. There is no evidence-based
guideline to diagnose AF in patients who have had a stroke or TIA.
An objevtive related to this study is to reduce the probability of a relapse
CVA or TIA.

The definition of this problem is: "Can paroxysmal atrial fibrillation be found
in patients with signs and symptoms (fitting with atrial fibrillation), left
atrial enlargement at ECG, left ventricle hypertrophy at ECG, premature
heartbeats at ECG (with a heartbeat more than 70 beats per minute),
hyperthyroid and cerebral ischemia in several flow areas?"
We will study patients who survive an ischaemic stroke or TIA, seen at the
outpatient TIA-clinic, by which at least one of the possible signs occurs
(identified in literature)


(see also page 4 and 5 of the study-protocol)

The TIA-AF-project is defined diagnostic study at the diagnosis atrial
fibrillation. It is a cross-sectional design by which the diagnosis atrial
fibrillation is determined by a cardiologist
The patients will be included by the TIA-AF-flowchart (see annex 1 of the
study-protocol).
Patients with AF in history and patients with AF on ECG at outpatient
TIA-clinic will be excluded.
The methodology of diagnostic measure is the golden standard 'rapid-access
cardio-AF', by which is used a 7-days holterregistration in stead of a 24-hours
holterregistration.

Currently patients are referred to the cardiologist to diagnose a
cardio-embolic-source. The patient recieves diagnostic examinations (ECG,
24-hours-holter and cardio-multiple-image) and an interview to discuss the
results on several visits (in several days). In this study we will make use of
the outpatient rapid access cardio-AF-clinic, by which patients recieve several
examinations with an interview to discuss the results within the same day. This
will probably be less aggravating for the patient (one visit in stead of
several visits).

In this study we will use a 7-days-holterregistration instead of a 24-hours
holterregistration. The 7-days-holterregistration is considered to be more
aggravating for the patient. The riks associated with using a 7-days holter are
small or non-existent. During the holterregistration the patient cannot take a
shower; however the patient can switch the holter off before taking a shower
and switch it back on the holter after the shower.