Patients who had atrial fibrillation ablation between February 19 th 2010 to September 26 th 2014 were analyzed via chart reviews. Statistical analysis was performed. Also Ablation protocol is mentioned.
Atrial Fibrillation Ablation Procedure
Standard venous access using three 8 French sheaths were inserted into the right common femoral vein using ultrasound guidance. Likewise, a 9 French sheath into the left common femoral vein and a to cycle length of 200. Patients with inducible atrial fibrillation or 7 French sheath into the right internal jugular vein.
Transesophageal echocardiogram had been done prior to the procedure as well as a 64 slice CAT scan. Anatomy obtained from both modalities was integrated with electroanatomical mapping anatomy obtained from EnSite Velocity System.
Anticoagulation was done by keeping patients on Coumadin. Target INR between 2 and 3 before the procedure, as well as after the procedure for at least 3 months. Periodic INRs were done before and after the procedure.
General anesthesia with hemodynamic monitoring was done in all patients with the anesthesia team. Arterial lines were inserted through the femoral arteries to confirm hemodynamic stability.
AcuNav intracardiac echocardiogram 8 French was inserted into the left common femoral vein and placed into the right atrium, it was used to monitor transeptal puncture as well as confirming catheter stability and position, it was also used to evaluate contact of catheter during ablation and to provide safety guards for early detection of complications.
Duodecapolar catheters were inserted through the right internal jugular vein into the coronary sinus with the proximal poles in the high right atrium. Right ventricular quadripolar catheter inserted into the right ventricle.
Two transseptal punctures were done using Across system. This was done under intracardiac echo as well as fluoroscopy guidance. This was also continued to be monitored with hemodynamic guidance. SafeSept wire was used to avoid through and through punctures.
A spiral catheter was used to obtain electroanatomical mapping of the left atrium which was later merged with CT imaging anatomy.
Esophageal temperature probe was advanced into the esophagus and intermittently repositioned in close proximity to the ablating catheter. This was important to evaluate change in temperature during ablation. Any significant rise of more than 0.5° was enough to consider lowering the wattage output, as well as moving to another area. Power was titrated at 20 watts with an irrigation catheter in areas close to the esophagus.
All patients had pulmonary vein antral isolation isolation, care was taken to insure entrance and exit block from the pulmonary viens, later during the last year care was also given to achieve delayed signal into the veins prior to complete isolation. Multiple substrate modifications including left atrial roof line, mitral annular line and cavotricuspid isthmus line, other lines and complex fractionated atrial electrograms were also targeted in patients with persistent or long lasting persistent atrial fibrillation.
Anticoagulation was done with heparin bolus, as well as drip to maintain ACT more than 350 and less than 400, frequent ACTs were checked every 15 minutes, and heparin readjusted until ACTs remained stable.
Left atrial pressure, as well as patient’s inputs and outputs were continuously monitored throughout the procedure. Ablation done using saline irrigation catheters with power of 35 watts except for areas close to the esophagus or inside the veins it was titrated to 20 watts. Care was done to avoid ablation inside veins and rather to isolate veins just outside the os.
After ablation, if the patient continued to have atrial fibrillation, DC cardioversion was done.
Isuprel started in all patients with decremental atrial pacing down to cycle length of 200. Patients with inducible atrial fibrillation or flutter received further ablation when appropriate.
Protamine 30 to 40 mg was given, and catheters were removed at the end of the procedure. Hemostasis achieved by manual pressure at venous access sites.
Patients stayed overnight and typically sent home the second day. Average lengths of hospital stay 2.4 days. Most common reason to extend hospital stay is for patient to achieve therapeutic INR.
After ablation, all patients were placed on anticoagulant therapy and observed with telemetry monitoring for 24 to 48 hours. For persistent or long lasting persistent AF patients who had resistant and long-lasting arrhythmia, we thought that antiarrhythmic drugs could improve the likelihood of modifying atrial electrical remodeling and maintaining sinus rhythm. Therefore, such patients were discharged with 1 drug that, in the past, seemed to be well tolerated although unable to prevent AF.
Patient with Paroxysmal atrial fibrillation antiarrhythmic medication were discontinued 5 days prior to the procedure and were restarted if patients experienced recurrence or have multiple comorbidities. Patients on amiodarone were discontinued > 1 month prior to procedure.
Attempts were made to remove antiarrhythmics after 3 months in the absence of AF recurrence, unless other risk factors were present. Other medications, including digitalis, β-blockers and calcium antagonists, were prescribed when indicated.
All patients were followed up periodically with a periodic Holter monitor done every 3 months 1st year, as well as EKGs to evaluate for recurrence if the patient maintained sinus rhythm. Patients with pacemakers had device interrogation every 3 months. All patients had periodic cardiology visits and EKGs every 3-6 months thereafter and if symptomatic repeated holter or 30 day event monitors (Ambulatory Cardiac Telemetry) were performed.
The procedure was considered successful if no recurrences of AF lasting >30 s were present post blanking period (3 months post procedure).