Our observational study aim to to evaluate the incidence of Tachyarrhythmia in patients with congenital heart diseases (corrected/non corrected) and the effectiveness of catheter ablation.RF catheter ablation was performed to all patients and follow up for recurrence was done for one year.

This is a prospective cohort observational study including patients with CHD undergoing attempted catheter ablation.Baseline information is collected before catheter ablation. Data include demographic characteristics (age, gender), type of CHD, dates and types of previous cardiac surgeries, comorbidities, Electrocardiographic (ECG) and ECG recordings Holter (24h to 7 days) during tachycardia to document arrhythmia type and the presence of resting pre-excitation, palpitations attacks (frequency, duration, ICU / ER admission, ECG and mode of termination), history of supraventricular and ventricular arrhythmias, pharmacological therapy, previous catheter ablation and cardiac imaging (echocardiography with or without cardiac magnetic resonance imaging or cardiac computed tomography).

RF catheter ablation is performed after obtaining informed consent from all patients. Antiarrhythmic medication is in most cases discontinued for at least five half-lives before the procedure. Prepping and draping are performed according to standard hospital protocols under complete local aseptic conditions. Variable sized sheaths are introduced percutaneously via the right/left femoral/Jugular/ subclavian vein. Under fluoroscopic guidance, three electrode catheters are positioned as follows: at the high right atrium, from the His bundle region to the right ventricle, and in the coronary sinus (CS) ostium region. Bipolar intracardiac electro grams filtered between 30 and 500 Hz along with the 12- lead surface ECG were simultaneously recorded and stored digitally on a computerized multichannel EP recording system. Cases are filtered according to complexity and availability of 3D to conventional group for simple cases where RF ablation will be done guided by Conventional fluoroscopic guidance and for complicated cases RF ablation is guided by 3d electro anatomical mapping system.

Inclusion Criteria:

• Patients with congenital heart diseases (corrected / non corrected) with documented arrhythmia
• Patients with congenital heart diseases without documented arrhythmia but frequent palpitations.

Exclusion Criteria:

• Pregnant
• Patients with unstable hemodynamics
• End stage diseases e.g.: cancer stage IV

patients with congenital heart diseases (corrected / non corrected) with arrhythmia