A single-center clinical trial on the analysis of intracardiac atrial electrogram mapping before and after ablation with the HD Grid Mapping Catheter and Ensite X Software, as a prospective study.

This study was designed to determine the efficacy of substrate ablation using HD Grid Mapping Catheter could collected more AF electrogram and facilitate the mapping resolution and driver identification in AF patients who required substrate modification. This study is a prospective, single-center in which patients with AF who will receive catheter ablation.

The priority of substrate modification would be determined by the mapping with the HD Grid mapping catheter. The end-point of ablation is non-inducible of AF or AFL. The procedure time, fluoroscopic time, procedural termination rate, and recurrence of atrial arrhythmia would be collected. If the flutter or the non-PV triggers were inducible, isthmus ablation and the non-PV trigger ablation will be performed accordingly.

Inclusion Criteria:

1. Patents who sign the informed consent forms, and allow to be followed.
2. Symptomatic AF refractory or intolerant to at least one Class 1 or 3 antiarrhythmic medication.
3. Patients with age equal or greater than 20 years old regardless of gender.

Exclusion Criteria:

1. The presence of a atrial or ventricular thrombus.
2. Patients who are allergic to or unsuitable for use with the contrast media.
3. Pregnant patients or patients who are unavailable to receive X-ray.
4. Patients with renal insufficiency.
5. Patients had autonomic nervous system disorder (e.g. respiratory apnea)
6. Patients with age less than 20 years old or greater than 80 years old regardless of gender.

Criteria for inclusion (same as current inclusion criteria for catheter ablation of

AF):

1. Patents who sign the informed consent forms, and allow to be followed.
2. Symptomatic AF refractory or intolerant to at least one Class 1 or 3 antiarrhythmic medication.
3. Patients with age equal or greater than 20 years old regardless of gender.

Criteria for exclusion (same as current inclusion criteria for catheter ablation of

AF):

1. The presence of a atrial or ventricular thrombus.
2. Patients who are allergic to or unsuitable for use with the contrast media.
3. Pregnant patients or patients who are unavailable to receive X-ray.
4. Patients with renal insufficiency.
5. Patients had autonomic nervous system disorder (e.g. respiratory apnea)
6. Patients with age less than 20 years old or greater than 80 years old regardless of gender.