Rebecca McCall

Atrial arrhythmias after single-ring isolation of the posterior left atrium and pulmonary veins for atrial fibrillation: mechanisms and management.

Background—Single-ring isolation of the posterior left atrium is feasible, but the incidence and mechanisms of postprocedural arrhythmias have not been described in detail. Methods and Results—The first 100 consecutive patients (58.8±11.2 years old, 80 male) who underwent single-ring isolation for atrial fibrillation (66 intermittent, 18 persistent, 16 long-standing persistent) were followed up for 9.1±4.5 months. Recurrences were diagnosed by clinical symptoms and Holter monitoring. Patients with recurrences of sustained atrial arrhythmia >3 months after the procedure were offered a repeat procedure and were studied to determine the mechanisms of recurrence. Forty-six patients (46%) experienced sustained postprocedural atrial arrhythmias (35 had atrial fibrillation, and 34 had atrial flutter). Of these, 34 required a second procedure 7.0±3.1 months after their initial procedure. Reconnection of the posterior left atrium was seen in all patients with atrial fibrillation. Atrial flutter was most commonly due to mitral isthmus-dependent macroreentry (n=8, cycle length 368±116 ms) or macroreentry through 2 gaps in the ring of lesions (n=6, cycle length 328±115 ms). Posterior left atrium reisolation was achieved at the second procedure in all patients. Atrial flutter was successfully ablated and rendered noninducible in all patients. Six months after their last procedure, the Kaplan-Meier estimate of freedom from recurrence for all 100 patients was 81±5%. Conclusions—Atrial fibrillation and atrial flutter recurrence is common after single-ring isolation. Reconnection of the posterior left atrium and macroreentry are the common mechanisms. Repeat ablation results in satisfactory short-term outcomes.

Single-Ring Posterior Left Atrial (Box) Isolation Results in a Different Mode of Recurrence Compared With Wide Antral Pulmonary Vein Isolation on Long-Term Follow-Up Longer Atrial Fibrillation–Free Survival Time but Similar Survival Time Free of Any Atrial Arrhythmia

Background—Electric isolation of the pulmonary veins and posterior left atrium with a single ring of radiofrequency lesions (single-ring isolation [SRI]) may result in fewer atrial fibrillation (AF) recurrences than wide antral pulmonary vein isolation (wide antral isolation [WAI]) by abolishing extravenous AF triggers. The effect of mitral isthmus line (MIL) ablation on outcomes after SRI has not previously been assessed. Methods and Results—We randomly assigned 220 consecutive patients (58±10 years old; 82% men) with highly symptomatic AF (61% paroxysmal, 39% persistent/longstanding persistent) to undergo either SRI or WAI. Half of each cohort was also randomly allocated to have left lateral MIL ablation (2×2 factorial study design). Patients were followed clinically and with 7-day Holter studies for arrhythmia recurrences. The primary end points were recurrence of AF and organized atrial tachyarrhythmias. AF-free survival at 2 years was better after SRI (74% [95% CI, 65%–82%]) than WAI (61% [51%–70%]; P=0.031). Organized atrial tachyarrhythmia–free survival was similar after SRI and WAI (67% [57%–75%] ersus 64% [54%–72%], respectively, at 2 years; P=0.988). MIL ablation resulted in better 2-year organized atrial tachyarrhythmia–free survival (71% [62%–79%] versus 60% [50%–69%]; P=0.07), which approached statistical significance. Survival free of any atrial arrhythmia after one procedure was not significantly affected by isolation technique or MIL ablation. Conclusions—SRI resulted in fewer AF recurrences compared with WAI on long-term follow-up but did not reduce the recurrence of all atrial arrhythmias. MIL ablation may reduce organized atrial tachyarrhythmia recurrences. Clinical Trial Registration—http://www.anzctr.org.au; ACTRN12606000467538.

Esophageal hematoma complicating catheter ablation for atrial fibrillation.

Significant injury to the esophagus during ablation for atrial fibrillation is rare but may be devastating. Esophageal fistulas and injury to branches of the vagus nerve resulting in gastric stasis have previously been described. In this case report, we describe another type of esophageal injury associated with catheter ablation for atrial fibrillation. The patient experienced chest pain and vomiting on recovery from anesthesia. Echocardiography and computerized tomography were used to identify a large esophageal hematoma. The hematoma was treated conservatively and the patient recovered fully after several weeks.

Restrictive cardiomyopathy versus constrictive pericarditis: making the distinction using tissue Doppler imaging

Although the primary cause of constrictive pericarditis is entirely different to that of restrictive cardiomyopathy, the two often present with very similar clinical findings. As such, making the distinction between the two is a diagnostic challenge. We report a case that highlights how tissue Doppler imaging may simplify the distinction between pericardial constriction and myocardial restriction.

Atrial Arrhythmias After Single-Ring Isolation of the Posterior Left Atrium and Pulmonary Veins for Atrial FibrillationCLINICAL PERSPECTIVE

Background—Single-ring isolation of the posterior left atrium is feasible, but the incidence and mechanisms of postprocedural arrhythmias have not been described in detail. Methods and Results—The first 100 consecutive patients (58.8±11.2 years old, 80 male) who underwent single-ring isolation for atrial fibrillation (66 intermittent, 18 persistent, 16 long-standing persistent) were followed up for 9.1±4.5 months. Recurrences were diagnosed by clinical symptoms and Holter monitoring. Patients with recurrences of sustained atrial arrhythmia >3 months after the procedure were offered a repeat procedure and were studied to determine the mechanisms of recurrence. Forty-six patients (46%) experienced sustained postprocedural atrial arrhythmias (35 had atrial fibrillation, and 34 had atrial flutter). Of these, 34 required a second procedure 7.0±3.1 months after their initial procedure. Reconnection of the posterior left atrium was seen in all patients with atrial fibrillation. Atrial flutter was most commonly due to mitral isthmus-dependent macroreentry (n=8, cycle length 368±116 ms) or macroreentry through 2 gaps in the ring of lesions (n=6, cycle length 328±115 ms). Posterior left atrium reisolation was achieved at the second procedure in all patients. Atrial flutter was successfully ablated and rendered noninducible in all patients. Six months after their last procedure, the Kaplan-Meier estimate of freedom from recurrence for all 100 patients was 81±5%. Conclusions—Atrial fibrillation and atrial flutter recurrence is common after single-ring isolation. Reconnection of the posterior left atrium and macroreentry are the common mechanisms. Repeat ablation results in satisfactory short-term outcomes.

Atrial Arrhythmias After Single-Ring Isolation of the Posterior Left Atrium and Pulmonary Veins for Atrial FibrillationCLINICAL PERSPECTIVE: Mechanisms and Management

Background—Single-ring isolation of the posterior left atrium is feasible, but the incidence and mechanisms of postprocedural arrhythmias have not been described in detail. Methods and Results—The first 100 consecutive patients (58.8±11.2 years old, 80 male) who underwent single-ring isolation for atrial fibrillation (66 intermittent, 18 persistent, 16 long-standing persistent) were followed up for 9.1±4.5 months. Recurrences were diagnosed by clinical symptoms and Holter monitoring. Patients with recurrences of sustained atrial arrhythmia >3 months after the procedure were offered a repeat procedure and were studied to determine the mechanisms of recurrence. Forty-six patients (46%) experienced sustained postprocedural atrial arrhythmias (35 had atrial fibrillation, and 34 had atrial flutter). Of these, 34 required a second procedure 7.0±3.1 months after their initial procedure. Reconnection of the posterior left atrium was seen in all patients with atrial fibrillation. Atrial flutter was most commonly due to mitral isthmus-dependent macroreentry (n=8, cycle length 368±116 ms) or macroreentry through 2 gaps in the ring of lesions (n=6, cycle length 328±115 ms). Posterior left atrium reisolation was achieved at the second procedure in all patients. Atrial flutter was successfully ablated and rendered noninducible in all patients. Six months after their last procedure, the Kaplan-Meier estimate of freedom from recurrence for all 100 patients was 81±5%. Conclusions—Atrial fibrillation and atrial flutter recurrence is common after single-ring isolation. Reconnection of the posterior left atrium and macroreentry are the common mechanisms. Repeat ablation results in satisfactory short-term outcomes.

Structural Changes Following Linear Ablation in the Left Atrium for Treatment of Atrial Fibrillation

A 67-year-old male underwent electrical isolation of the pulmonary veins for persistent atrial fibrillation. Two large rings of radiofrequency ablation lesions were placed around the ipsilateral vein pairs with an open irrigated 3.5-mm tip (Thermocool Navistar, Biosense Webster, Diamond Bar, CA, USA). Power levels of 30–40 W were used, with temperature limited to 50 ̊C. The rings touched posteriorly and additional ablation was performed at selected sites within the rings of ablation to obtain full electrical isolation of the veins. Ablation was guided by a three-dimensional rendering of a cardiac contrast-enhanced CT (CARTO Merge, Biosense Webster). The patient continued to experience frequent intermittent atrial fibrillation. A second procedure was performed 8 months after the first (Fig. 1). A CT scan was performed,