Diagnosing Brugada Syndrome
The heart muscle itself is not abnormal, so patients can be
asymptomatic until their first episode of ventricular
tachycardia. Although imaging studies, such as cardiac
ultrasounds, are typically normal, patients with Brugada have a
characteristic pattern on their electrocardiogram (ECG) that often
leads to the diagnosis. One of the difficulties in the disorder is
that these ECG findings can come and go, making the diagnosis
difficult to make. Exposure to inciting medications in a controlled
setting and catheter-based stimulation studies are sometimes needed
for diagnostic purposes.
The diagnosis of Brugada syndrome can be difficult to make. Most
patients do not suffer any symptoms until their first episode of
ventricular tachycardia, which can cause dizziness, syncope (passing
out) or even death. These episodes typically occur during sleep. The
correct diagnosis hinges on the presence of the characteristic ECG
findings in someone who had syncope or near sudden death. The ECG
findings alone, without syncope, are not sufficient to make the
diagnosis of "Brugada syndrome." Those who have ECG findings
suspicious for the diagnosis, but who have not had syncope, are said
to have a "Brugada pattern," and are treated
differently.
The classic ECG findings of a classic "type I Brugada
pattern" consists of a right bundle branch block with
down-sloping ST segment elevations greater than 2mm and inverted T
waves in leads V1 through V3. Type 2 and 3 Brugada patterns also have
a right bundle branch block-like pattern, but the ST segment has a
saddleback appearance and T wave inversion is not as marked.
There is currently no "cure" for Brugada syndrome and no
medications that eliminate the risk of sudden death. However placement
of an implantable cardiac defibrillator nearly eliminates the risk of
dying suddenly from ventricular tachycardia. There are recommendations
against competitive sports and potential complications from
defibrillators. However, patients with a diagnosis of Brugada syndrome
who have defibrillators can essentially lead normal, productive
lives.
Diagnosis techniques: