Catheter Ablation

What types of rhythms are treated with radiofrequency catheter ablation?

Normal Conduction of the Heart

RFCA can be used to treat:

1. AV Nodal Reentrant Tachycardia (AVNRT)
2. Accessory Pathway Tachycardias (AVRT)
3. Atrial fibrillation
4. Atrial flutter
5. Ventricular Tachycardia

How the procedure is done

The radiofrequency catheter ablation is performed in the cardiac catheterisation lab. The staff will be wearing sterile gloves, gowns, caps and masks. A technician will place several ECG electrodes on your chest to monitor the heart rate and rhythm during the procedure, and a gel pad on your back. A blood pressure cuff will be put around your arm and oxygen saturation metre will be placed around your finger. Your groin and left chest area will be washed with antiseptic solution and sterile sheets will be placed over your body. Do not touch this sheet with your hands because it should remain germ-free. Before the insertion of the catheters (special insulated electrical wires), intravenous injections of sedatives will be given.

Following the injection of local anesthetic, the catheters will be inserted usually via the left subclavian vein (near the left shoulder) and either femoral veins (at the both groins). The catheters are positioned in the heart by the operators using X ray imaging guidance. During the study, the patient may feel a rapid heart rate due to the pacing or the induction of the tachycardia. The EPS gives an electrical map of the heart and determines the cause of the arrhythmia (electrical malfunction). The exact site is then localized by the electrical signals obtained from the tip of the catheter. Once the abnormal site is precisely localized, radiofrequency energy is then delivered via the tip of the catheter to destroy or “burn” (temperature of 60 to 70°C only) the abnormal tissue. The size of the "burn" is very small and is usually about 5 mm in diameter only and hence very precise localization is necessary for it to succeed. Radiofrequency energy is delivered for usually 30-60 seconds, to ablate the abnormal focus. The procedure usually takes about 1 2 hours. After the ablation, the patient waits for another 15-30 minutes in the lab to ensure that there is no immediate recurrence.