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Drs. Akar, Knight, and Mithilesh presented several case studies to help explain key procedures and techniques in the management of arrhythmias after ablation of atrial fibrillation.
Joseph Akar, MD, MRCP, FACC, Division of Cardiology, Yale University School of Medicine; Mithilesh K Das, Associate Professor of Clinical Medicine, Krannert Institute of Cardiology, Chief, Cardiac Electrophysiology, Roudebush VA Medical Center, Indiana University School of Medicine; Bradley P Knight, MD, FACC, Professor of Internal Medicine-Cardiology, University of Chicago
Dr. Knight explained before this session that it was intended to be as informal as possible; he told attendees to feel free to interrupt with the supplied microphones, which only a couple people took advantage of, one perhaps a bit too aggressively.
Dr. Das began with a review of post-atrial fibrillation (AF) ablation for atrial tachycardia (AT). He explained that the prevalence of AT/AF is based on initial AF ablation therapy, and that the recurrent of AT/AF after catheter ablation jumps from 15% to 45% within days. Moving very quickly through his presentation, the speaker next noted that structural heart disease patients have a higher recurrence (74%) of these conditions. Other key points he made were as follows:
Knight continued the session, saying to approach cases of these conditions by paying careful attention to what was done before-what techniques were used in a previous ablation and if the patient has had cardiac surgery. He focused first on a case of a 61-year-old woman with atrial fibrillation 5 months after pulmonary vein isolation (PVI) and cavotricuspid isthmus (CTI) ablation. The cardiology team on the case excluded the right atrium first. He explained that "once you're in the left atrium, inspect all pulmonary veins and exclude those that can be, exclude the left atrial appendage, and exclude the roof."
In this case study, after several lesions along the roof and no slowing of termination, the cardiologists had to re-isolate PVs. "If you're not making progress," said Knight, "re-evaluate the mechanism of the tachycardia." In this case, the proposed mechanism was a figure of 8 reentry around the mitral annulus and left PVs.
Knight next showed a video clip that displayed the effect of manual color scale adjustment. He advised to always adjust the color to expand them. In the case study, they were able to see what appeared as micro-reentry as opposed to what they thought was focal with a limited color scale.
Knight closed his section of the session with a case of atrial tachycardias after RFA ablation for AF. He explained that it is more practical to bring a patient into the lab when they are having a tachycardia, even if it means having them sit in the hospital for a day.
Dr. Akar, quite possibly the fastest speaker on the planet (maybe because he only had 12 minutes to speak), closed the session. Blazing through, he made the following key points:
In closing, Akar advies to perform entrainment mapping from multiple sites but be mindful of its limitations, use entrainment mapping to define macroreentrant circuits, consider other circuits if the cycle length changes, Don't learn as you burn by always defining the circuits, target the site of earliest activation for focal AT, and target the critical isthmus for macroreentrant circuits.