Introduction:
Post-ablation radiofrequency tissue friability has been described; however, tissue friability post cryoablation has not been well studied. We report a case of left atrial perforation with normal contact force radiofrequency ablation 22 days after initial cryoballoon ablation.
Description:
A 59-year-old male with persistent atrial fibrillation, severe biatrial enlargement, non-ischemic cardiomyopathy (EF of 20%), underwent initial cryoballoon pulmonary vein isolation with left atrial roof cryoablation with restoration of sinus rhythm and no complications. Patient presented 22 days later with sustained atrial flutter and heart rate over 130 bpm refractory to aggressive medical management, cardioversion, and acute on chronic congestive heart failure. Early re-ablation was performed with electrophysiology study and 3D activation map confirming ectopic atrial tachycardia foci arising from left atrial roof, anterior to the border of previously cryo-ablated region. St. Jude TactiCath™ contact force ablation catheter, was used to ablate this foci, and termination within 5 seconds of ablation was observed. Using the Force-Time Integral index to guide further ablation, the surrounding area was ablated for an additional 20 seconds at 30 W with a maximum recorded contact force throughout the procedure of 35 grams, and an average of 10-15 grams.A decrease in systolic blood pressure from 120 mmHg to 80 mmHg was noted, and intracardiac ultrasound confirmed 1.5 cm of pericardial effusion. Successful pericardiocentesis and reversal of anticoagulation was performed with ongoing bleeding, and eventual surgical intervention was required. On direct visualization during surgery, the left atrial roof perforation was confirmed, and was noted to be very friable and difficult to retain suture for repair. Patient did well post-operatively and was discharged with no recurrence of arrhythmias.
Conclusions:
Despite standard of care monitoring, including force-time integral index and contact-sensing catheters, atrial perforation occurred likely due to increased tissue friability post initial cryoablation. The optimal timing for repeat ablation is not completely understood, and extreme caution and avoidance of early re-ablation risk is prudent.
Contact force and force-time integral in atrial radiofrequency ablation predict transmurality of lesions
