Outcomes of adjunct posterior wall isolation in atrial fibrillation patients with cardiac implantable electronic devices.

BACKGROUND: Although pulmonary vein isolation (PVI) remains the cornerstone of catheter ablation of atrial fibrillation (AF), several studies have illustrated clinical benefits associated with PVI with posterior wall isolation (PWI). METHODS: This retrospective study investigated the outcomes of PVI alone versus PVI+PWI performed using the cryoballoon in patients with cardiac implantable electronic devices (CIEDs) and paroxysmal AF (PAF) or persistent AF (PersAF). RESULTS: Acute PVI was achieved in all patients using cryoballoon ablation. Compared to PVI alone, PVI+PWI was associated with longer cryoablation, fluoroscopy, and total procedure times. Adjunct radiofrequency was required to complete PWI in 29/77 patients (37.7%). Adverse events were similar with PVI alone versus PVI+PWI. But at 24 ± 7 months of follow-up, not only cryoballoon PVI+PWI was associated with improved freedom from recurrent AF (74.3% vs. 46.0%, P = .007) and all atrial tachyarrhythmias (71.4% vs. 38.1%, P = .001) in patients with PersAF, cryoballoon PVI+PWI also yielded greater freedom from AF (88.1% vs. 63.7%, P = .003) and all atrial tachyarrhythmias (83.3% vs. 60.8%, P = .008) in those with PAF. Additionally, PVI+PWI was associated with higher reductions in atrial tachyarrhythmia burden (97.9% vs. 91.6%, P < .001), need for cardioversion (5.2% vs. 23.6%, P < .001) and repeat catheter ablation (10.4% vs. 26.1%, P = .005), and a longer time-to-arrhythmia recurrence (16 ± 6 months vs. 8 ± 5 months, P < .001) in both PersAF and PAF patients. CONCLUSION: In CIED patients with PersAF or PAF, cryoballoon PVI+PWI is associated with a greater freedom from recurrent AF and atrial tachyarrhythmias, as compared to PVI alone during long-term follow-up.

Pulmonary Vein Isolation With and Without Posterior Wall Isolation in Paroxysmal Atrial Fibrillation: IMPPROVE-PAF Trial.

BACKGROUND: Prior studies have demonstrated clinical benefits associated with cryoballoon pulmonary vein isolation (PVI) and concomitant posterior wall isolation (PWI) in patients with persistent atrial fibrillation (AF). However, the role for this approach in patients with paroxysmal atrial fibrillation (PAF) remains unclear. OBJECTIVES: This study investigated the acute and long-term outcomes of PVI vs PVI+PWI using cryoballoon in patients with symptomatic PAF. METHODS: This retrospective study (NCT05296824) examined the outcomes of cryoballoon PVI (n = 1,342) vs cryoballoon PVI+PWI (n = 442) in patients with symptomatic PAF during long-term follow-up. Using the nearest-neighbor method, a 1:1 matched sample of patients receiving PVI alone and PVI+PWI was created. RESULTS: The matched cohort consisted of 320 patients (PVI: n = 160; PVI+PWI: n = 160). PVI+PWI was associated with longer cryoablation (23 ± 10 minutes vs 42 ± 11 minutes; P < 0.001) and procedure times (103 ± 24 minutes vs 127 ± 14 minutes; P < 0.001). In 39 (24.4%) of 160 patients, adjunct radiofrequency ablation was required for PVI+PWI. Adverse event rates were similar (PVI 3.8% vs PVI+PWI 1.9%; P = 0.31). Though there were no differences at 12 months, freedom from all atrial arrhythmias (67.5% vs 45.0%; P < 0.001) and AF (75.6% vs 55.0%; P < 0.001) were significantly greater with PVI+PWI vs PVI alone at 39 ± 9 months of follow-up. PVI+PWI was also associated with reduced long-term need for cardioversion (16.9% vs 27.5%; P = 0.02) and repeat catheter ablation (11.9% vs 26.3%; P = 0.001), and emerged as the only significant predictor of freedom from recurrent AF (HR: 2.79; 95% CI: 1.64-4.74; P < 0.001). CONCLUSIONS: Compared with cryoballoon PVI, cryoballoon PVI+PWI appears to be associated with greater freedom from recurrent atrial arrhythmias and AF in patients with PAF during long-term follow-up >3 years.

Safety of ventricular tachycardia ablation in clinical practice: findings from 9699 hospital discharge records.

BACKGROUND: Outcomes of ventricular tachycardia (VT) ablation have been described in clinical trials and single-center studies. We assessed the safety of VT ablation in clinical practice. METHODS AND RESULTS: Using administrative hospitalization data between 1994 and 2011, we identified hospitalizations with primary diagnosis of VT (International Classification of Diseases-9 Clinical Modification code: 427.1) and cardiac ablation (International Classification of Diseases-9 Clinical Modification code: 37.34). We quantified in-hospital adverse events (AEs), including death, stroke, intracerebral hemorrhage, pericardial complications, hematoma or hemorrhage, blood transfusion, or cardiogenic shock. Secondary outcomes included major AEs (stroke, tamponade, or death) and death. Multivariable mixed effects models identified patient and hospital characteristics associated with AEs. Of 9699 hospitalizations with VT ablations (age, 56.5 ± 17.6; 60.1% men), AEs were reported in 825 (8.5%), major AEs in 295 (3.0%), and death in 110 (1.1%). Heart failure had the strongest association with death (odds ratio, 5.52; 95% confidence interval, 2.97-10.3) and major AE (odds ratio, 2.99; 95% confidence interval, 2.15-4.16). Anemia (odds ratio, 4.84; 95% confidence interval, 3.79-6.19) and unscheduled admission (odds ratio, 1.64; 95% confidence interval, 1.37-1.97) were associated with AEs. During the study period, incidence of AEs increased from 9.2% to 12.8% as did the burden of AE risk factors (0.034 patient/y; P < 0.001). Hospital volume > 25 cases/y was associated with fewer AEs compared with lower volume centers (6.4% versus 8.8%; P = 0.008). CONCLUSIONS: VT ablation-associated AE rates in clinical practice are similar to those reported in the literature. Over time rates have increased as have the number of AE risk factors per patient. Ablations done electively and at hospitals with higher procedural volume are associated with lower incidence of AEs.

Endocardial electrogram characteristics of epicardial ventricular arrhythmias.

INTRODUCTION: While most ventricular arrhythmias (VA) can be ablated successfully using an endocardial (endo) approach, epicardial (epi) mapping and ablation is sometimes required. There may be suggestive clues on the surface electrocardiogram; however, identification of an epi origin of VA with certainty remains problematic. METHODS AND RESULTS: All patients referred for ablation of ventricular tachycardia or frequent ventricular ectopy from June 2007 to July 2011 were evaluated. Patients with completed endo and epi electroanatomical activation maps of an epi VA were included (n = 10). Bipolar electrograms (EGMs) in the area of earliest endo activation were analyzed and compared to the area of early epi activation. An EGM component was characterized as far field if it was monophasic and there was inability to capture. We identified 3 characteristics from endo mapping that consistently indicated need for epi ablation: (1) Diffusely early activation (>2 cm(2) region of sites with equally earliest activation within 10 milliseconds). (2) Sequence of a far-field EGM followed by a near-field EGM in the region of earliest endo activation. (3) Inability to capture the far-field component of the earliest EGM (stim-QRS < egm-QRS time) or reproduce morphological features of the VA complex with stimulation at the earliest endo site of activation. CONCLUSIONS: The presence of a diffusely early area of activation and inability to capture a far-field endo EGM indicates that epi ablation may be needed to eliminate a VA.

Use of stored implanted cardiac defibrillator electrograms in catheter ablation of ventricular fibrillation.

BACKGROUND: Ventricular fibrillation (VF) can be abolished by targeting triggering ventricular ectopy, most often originating in the Purkinje network or right ventricular outflow tract (RVOT). This strategy relies upon the induction of premature ventricular complex (PVC) and/or VF. We sought to evaluate a VF ablation strategy that utilizes analysis of stored implantable cardioverter defibrillator (ICD) electrograms. METHODS: Eleven consecutive patients experiencing frequent VF episodes (≥three episodes in prior month) underwent electrophysiology study and ablation of VF triggers. PVC and VF induction was intentionally avoided or not possible in all of these patients. Pacemapping at likely sites for PVC triggers of VF using an analysis of the morphology and relative timing of the stored far- and near-field ICD electrograms of VF triggers was used to identify potential culprit locations. Radiofrequency energy was applied to these sites for ablation of the identified VF trigger. RESULTS: Areas targeted for ablation included the left posterior fascicle (six), left anterior fascicle (three), RVOT (three) and left ventricular outflow tract (one); two patients had two separate triggers. Ablation was completed successfully without any complications. With a mean follow-up of 288 days (range 45-649), 10 patients are free of VF. CONCLUSION: Ablation of VF triggers can be performed successfully with good short-term outcomes in patients with and without underlying heart disease. Use of stored ICD electrograms with a focus on likely target areas permit ablation without the need for PVC or VF induction. This can be useful when ectopy is not present for mapping and to avoid potentially dangerous initiation of multiple episodes of VF.

Post-pericardial injury syndrome after continuous-flow ventricular assistance.

We present a patient with post-pericardial injury syndrome (PPIS) that occurred after implantation of a continuous-flow left ventricular assistance device. Evidence supporting the diagnosis includes radiographic, electrocardiographic, and serologic markers. Recognition of this syndrome is important in this patient population to appropriately treat the patient as well as prevent unnecessary testing and prolonged hospitalization.