Flecainide is a Sodium Channel Blocker drug. It is used to prevent abnormal heart rhythms (antiarrhythmic). Flecainide blocks the faulty sodium channels and unmasks ECG changes in those patients who have Brugada syndrome. In patients with normal cardiac cells flecainide has little or no effect on the ECG. Preparation: Flecainide is administered through a vein in your arm and record your ECG every three minutes. The ECG will record how your heart reacts to Flecainide, this allows clinician to collect detailed information about potential arrhythmia. The Flecainide challenge is undertaken in a ward setting with cardiac monitoring. Before the procedure you will have a baseline electrocardiogram (ECG) recorded. A doctor will explain the procedure to you, then ask you to sign a consent form. You will then be given a gown to wear and an IV cannula will be inserted in your arm.
There will be equipment by your bedside, to monitor your heart rhythm and record your blood pressure. You will be awake during the test and able to talk to us.The nurse or doctor will connect you to the flecainide infusion, this may sting a little and you may feel some mild discomfort. You will then be connected to the ECG machine. Once the infusion is running your doctor will record the ECG at three-minute intervals for the duration of the test. Sometimes patients do complain of a metallic taste in mouth, numbness around the lips or blurred vision these side effects usually resolve quickly once the test is completed. If you do have any uncomfortable symptoms during the test for example, chest pain, dizziness, shortness of breath, please tell your nurse or doctor. Do not be alarmed that the doctor is looking closely at the ECG during the test, it does not mean there is anything wrong.
After the procedure you will be monitored for up to 6 hours. The IV line will then be removed after this time. You will be able to eat and drink. The doctor will discuss results and ongoing treatment plan with you and your family. You will normally be able to go home that day if the test is negative. If the test is positive you will be admitted overnight to monitor your heart rhythm and then be discharged in the morning. You can resume your normal daily activities (walking, bathing, showering, etc.) and return to work upon discharge from hospital.
The complications associated with this procedure are very rare. It is important that you are aware that on rare occasions there are some risks associated with this procedure that may occur either during, or after the procedure.
In less than 1% of patients the Flecainide may cause your heart to go into a very fast ventricular rhythm, if this happens the doctor will need to correct your arrhythmia quickly by cardioversion. Cardioversion is a treatment for heart rhythms that are irregular. Before you are cardioverted you will be given a short-acting sedative to make you sleepy. Once you are asleep a special machine called a defibrillator is used to send electrical energy to the heart muscle to restore the normal rhythm and rate. There is a very low risk that you may experience an arrhythmia or develop ECG changes of Brugada after the Flecainide has been administered and hence your heart rhythm is monitored for several hours after the drug has been given, even if the test is negative.