Drug Provocation Test
Ajmaline Provocation Test
The ajmaline provocation test is a monitored ECG test used to unmask a Brugada pattern when the diagnosis is suspected but the resting ECG is not conclusive.
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Understanding the Test
What Is the Ajmaline Test?
Brugada syndrome can be difficult to diagnose because the characteristic ECG pattern may come and go. A person can have a normal ECG on one day and a typical pattern on another.
In an ajmaline provocation test, a sodium-channel-blocking medicine is given slowly into a vein while the ECG is recorded continuously. In people with the underlying condition, the medicine may bring out the type 1 Brugada pattern. The test is therefore a diagnostic tool that is performed only under close monitoring.
Indications
When the Test May Be Considered
Suspicious ECG
A pattern that suggests Brugada syndrome but does not meet diagnostic criteria.
Unexplained symptoms
Fainting or documented ventricular arrhythmia without another cause.
Family screening
Relatives of a person with Brugada syndrome, when assessment is recommended.
The decision to test is individual, and the test is not routine for everyone with palpitations or a non-specific ECG.
Procedure
How the Test Is Carried Out
Preparation
Review of history, medicines and baseline ECG.
Monitoring
Continuous ECG and blood pressure monitoring with resuscitation equipment on hand.
Infusion
The medicine is given slowly and the ECG is watched closely.
Stopping
The infusion is stopped if a diagnostic pattern or rhythm disturbance appears.
Observation
Monitoring continues until the ECG returns to baseline.
In more detail
Step by Step in More Detail
Preparation
Your team reviews your history, medicines and any recent illness. The test is usually postponed during fever or acute illness. You may be asked to fast and to adjust some medicines beforehand, as advised for you.
Baseline ECG
A resting ECG is recorded first, sometimes with the chest electrodes in additional positions, to provide a comparison.
Monitored environment
The test takes place with continuous ECG and blood-pressure monitoring, an intravenous line, and resuscitation equipment and trained staff immediately available.
Giving the medicine
A sodium-channel-blocking medicine is given slowly through the vein while the ECG is watched. The amount and rate are determined by the team and are not a matter for self-directed use.
The ECG response
Reading the ECG Response and Observation Afterwards
The team looks for the type 1 Brugada pattern, a coved ST-segment elevation in the right chest leads. The infusion is stopped when the pattern appears, when other rhythm disturbances or widening of the QRS complex occur, or when the planned amount has been given.
The ECG and symptoms are then observed until the ECG returns to baseline, and monitoring continues for a period set by the team. The result is explained and next steps are discussed, including risk assessment and advice for relatives. See Brugada Syndrome.
Safety and Results
Risks and How Results Are Used
Because the medicine can provoke rhythm disturbances in susceptible people, it is administered in a monitored setting by a team trained to respond, and risks are discussed beforehand.
A positive test supports the diagnosis of Brugada syndrome, which then leads to risk assessment and follow-up.
A negative test makes the diagnosis less likely but is interpreted together with the whole clinical picture.
Your physician will explain what the result means for you and your relatives. See Brugada Syndrome.
Questions
Frequently Asked Questions
Is the ajmaline test painful?
Do I need to prepare?
Your team will give you individual instructions. You may be asked to adjust some medicines and to avoid eating beforehand, and the test is usually postponed if you have a fever or are unwell. Do not change any medicine unless the team has told you to.
Can a negative test rule out Brugada syndrome?
It makes the diagnosis less likely, but it does not exclude it in every case. A positive test supports the diagnosis but is also interpreted with the rest of the clinical picture. Your physician will explain what the result means for you.
Should relatives be tested?
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