Oesophageal Probe Evaluation in Radiofrequency Ablation of Atrial Fibrillation (OPERA): results from a prospective randomized trial.

AIMS: The aim of the study was to determine the incidence of oesophageal lesions after radiofrequency ablation (RFA) of atrial fibrillation (AF) with or without the use of oesophageal temperature probes. METHODS AND RESULTS: Two hundred patients were prospectively randomized into two groups: the OPERA+ group underwent RFA using oesophageal probes (SensiTherm™); the OPERA- group received RFA using fixed energy levels of 25 W at the posterior wall without an oesophageal probe. All patients underwent post-interventional endoscopy and Holter-electrocardiogram after 6 months. (Clinical.Trials.gov: NCT03246594). One hundred patients were randomized in OPERA+ and 100 patients in OPERA-. The drop-out rate was 10%. In total, 18/180 (10%) patients developed endoscopically diagnosed oesophageal lesions (EDEL). There was no difference between the groups with 10/90 (11%) EDEL in OPERA+ vs. 8/90 (9%) in OPERA- (P = 0.62). Despite the higher power delivered at the posterior wall in OPERA+ [28 ± 4 vs. 25 ± 2 W (P = 0.001)], the average EDEL size was equal [5.7 ± 2.6 vs. 4.5 ± 1.7 mm (P = 0.38)]. The peak temperature did not correlate with EDEL size. During follow-up, no patient died. Only one patient in OPERA- required a specific therapy for treatment of the lesion. Cumulative AF recurrence after 6 (3-13) months was 28/87 (32%) vs. 34/88 (39%), P = 0.541. CONCLUSION: This first randomized study demonstrates that intraoesophageal temperature monitoring using the SensiTherm™ probe does not affect the probability of developing EDEL. The peak temperature measured by the thermoprobe seems not to correlate with the incidence of EDEL. Empiric energy reduction at the posterior wall did not affect the efficacy of the procedure.

Natural course of acquired pulmonary vein stenosis after radiofrequency ablation for atrial fibrillation-Is routine follow-up imaging indicated or not?

INTRODUCTION: Thermal injury during radiofrequency ablation (RFA) of atrial fibrillation (AF) can lead to pulmonary vein stenosis (PVS). The aim of the present study was to analyze the natural course of RFA-induced PVS with regard to the grade of stenosis, clinical symptoms, and mortality during long-term follow-up. METHODS AND RESULTS: All patients with follow-up imaging for radiofrequency-induced untreated PVS were retrospectively assessed. From 2004 to 2017, the total rate of PVS following AF ablation in our center was 0.78% (87 of 11 103). Thirty-eight patients with a total of 54 untreated PVS underwent follow-up including imaging scan. The mean degree of stenosis at the time of diagnosis was 57% ± 27% vs 45% ± 35% (P = .05) after a mean follow-up of 43 ± 31 months. There was a shift in severity of the PVS: 18 of 54 (33%) vs 16 of 54 (30%) severe PVS, 19 of 54 (35%) vs 10 of 54 (18%) moderate PVS, and 17 of 54 (32%) vs 28 of 54 (52%) mild PVS (P = .0001). The mean symptom score decreased significantly during follow-up (1.8 ± 1.0 vs 0.4 ± 0.5, P = .0001). Each of the four patients with progression of PVS underwent another pulmonary vein isolation for AF recurrence following pulmonary vein reconduction during follow-up period. CONCLUSION: This study showed a spontaneous reduction in stenosis grade and symptoms of PVS over a 3.5-year follow-up. Consequently, routine follow-up imaging of PVS seems not to be necessary. However, additional RF energy delivery to stenotic pulmonary veins should be avoided if possible. In case of conduction recovery, the ablation line should be done wide-antrally and follow-up imaging of PVS is recommended.

Epicardial adipose tissue thickness as an independent predictor of ventricular tachycardia recurrence following ablation.

BACKGROUND: Although several investigations have shown a relationship between increased epicardial adipose tissue (EAT) and atrial fibrillation (AF), the association between EAT and ventricular tachycardia (VT) has not been evaluated. OBJECTIVE: We investigated the association between EAT and postablation VT recurrence. METHODS: Sixty-one consecutive patients (mean age = 62.0 ± 13.9 years) undergoing VT ablation with preprocedural cardiovascular magnetic resonance imaging (CMR) were recruited. EAT thickness was measured using CMR in the right and left atrioventricular grooves (AVGs), right ventricular free wall, and anterior, inferior, and superior interventricular grooves. RESULTS: During a mean follow-up period of 392.9 ± 180.2 days, postablation VT recurrence occurred in 15 (24.6%) patients. EAT thickness was significantly higher in the VT recurrence group than in the nonrecurrent VT group at the right (18.7 ± 5.7 mm vs 14.1 ± 4.4 mm; P = .012) and left (13.3 ± 3.9 mm vs 10.4 ± 4.1 mm; P = .020) AVGs. The best cut-off points for predicting VT recurrence were calculated as 15.5 mm for the right AVG (area under receiver operating characteristic [ROC] curve = 0.74) and 11.5 mm for the left AVG (area under ROC curve = 0.72). Multivariate Cox regression analysis showed that preprocedural right AVG-EAT (hazard ratio: 1.2; 95% confidence interval: [1.06-1.39], P = .004) was the only independent predictor of VT recurrence after adjustment for covariates. Kaplan-Meier analysis showed a difference for postablation VT recurrence between the 2 groups, with right AVG-EAT thickness cut-off value of <15.5 mm vs ≥15.5 mm (log-rank, P = .003). CONCLUSIONS: We suggested a new possible imaging marker for risk stratification of postablation VT recurrence. A higher EAT may be associated with VT recurrence after catheter ablation of VTs.

Complex cases of acquired pulmonary vein stenosis after radiofrequency ablation: is surgical repair an option?

AIMS: Results of catheter based interventional treatment for pulmonary vein stenosis (PVS) following radiofrequency ablation (RFA) for atrial fibrillation remain suboptimal. Surgical repair may represent an alternative therapy, though long-term results have not been thoroughly investigated. METHODS AND RESULTS: We retrospectively assessed all patients in our centre undergoing surgical repair for radiofrequency-induced PVS. Data regarding surgical technique, clinical outcome, and rate of pulmonary vein (PV) restenosis were collected and analysed. Between 2004 and 2016, the rate for PVS resulting from RFA for atrial fibrillation in our institution was 0.79% (76/9633). During this period, five male patients with multiple PVS (3 ± 1) underwent surgical repair of a total of 13 symptomatic PVS. Surgery was performed in a standard setting under cardiopulmonary bypass. Stenotic veins were incised longitudinally followed by a patch augmentation plasty using either bovine pericard (n = 7) or polytetrafluoroethylene (PTFE) patches (n = 5). Localization of incision was on the anterior side of the PV only (n = 8) or on both the anterior and posterior sides (n = 4). In one PVS lesion, mechanical dilatation was sufficient. Long-term follow-up after 60 ± 69 months revealed an average restenosis rate of 38%. Restenosis was defined as narrowing >70%. All patients reported clinical improvement of symptoms at follow-up. CONCLUSION: Even in the era of wide circumferential lesions, PVS still occurs. While surgical PV patch plasty represents a valuable treatment option, restenosis remains an issue during follow-up. Nevertheless, surgical repair achieves highly acceptable long-term results for RFA-acquired PVS. Hence, it should be routinely discussed as a therapeutic option in cases with multiple PVS.

Rate of acquired pulmonary vein stenosis after ablation of atrial fibrillation referred to electroanatomical mapping systems: Does it matter?

BACKGROUND: Thermal injury during radiofrequency ablation (RFA) of atrial fibrillation (AF) can lead to pulmonary vein stenosis (PVS). It is currently unclear if routine screening for PVS by imaging (echocardiography, computed tomography) is clinically meaningful and if there is a correlation between PVS and the electroanatomical mapping system (EAMS) used for the ablation procedure. It was therefore investigated in the current single center experience. METHODS: All patients from January 2004 to December 2016 with the diagnosis of PVS after interventional ablation of AF by radiofrequency were retrospectively analyzed. From 2004 to 2007, transesophageal echocardiography was routinely performed as screening for RFA-acquired PVS (group A). Since 2008, diagnostics were only initiated in cases of clinical symptoms suggestive for PVS (group B). RESULTS: The overall PVS rate after interventional RFA for AF of the documented institution is 0.72% (70/9754). The incidence was not influenced by screening: group A had a 0.74% PVS rate and group B a 0.72% rate (NS). Referred to as the EAMS, there were significant differences: 20/4229 (0.5%) using CARTO®, 48/4510 (1.1%) using EnSite®, 1/853 (0.1%) using MediGuide®, and 1/162 (0.6%) using Rhythmia®. Since 2009, no significant difference between technologies was found. CONCLUSIONS: The present analysis of 9754 procedures revealed 70 cases of PVS. The incidence of PVS is not related to screening but to the application of different EAMS. Possible explanations are technological backgrounds (magnetic vs. electrical), learning curves, operator experience, and work-flow differences. Furthermore, incorporation of new technologies seems to be associated with higher incidences of PVS before workflows are optimized.

Catheter ablation of atrial fibrillation with nonfluoroscopic catheter visualization-a prospective randomized comparison.

PURPOSE: The application of a novel platform for nonfluoroscopic catheter sensor tracking within pre-recorded x-ray loops in the context of catheter ablation of atrial fibrillation (AF) demonstrated significant potential for reduction of fluoroscopy. We sought to provide the first prospective randomized comparison of fluoroscopy needs, procedure times, and complications in AF catheter ablation with or without additional use of nonfluoroscopic catheter visualization (NFCV). METHODS: Patients with AF were randomized into two groups before scheduled radiofrequency ablation: (1) using established mapping systems and fluoroscopy as needed (CONV group) or (2) with additional NFCV (NFCV group). All procedures were performed in the same lab using the same ablation catheter tip technology and the same mapping and ablation strategies. Primary endpoints were radiation time and dose. Secondary endpoints were procedural parameters, complications, and long-term success. RESULTS: A total of 80 patients (48 male patients, mean age 60 years, 46 patients with paroxysmal AF) were randomized into the two groups. Clinical parameters between both groups were similar. NFCV use reduced mean fluoroscopy time (1.9 vs. 13.2 min, p < 0.001) and mean dose (510 vs. 1549 Gycm2, p < 0.001) significantly. Procedural parameters were similar in the two groups. One conservatively treated groin complication occurred (1.3%). CONCLUSIONS: Radiation exposure can be significantly reduced by using the novel NFCV technology in addition to standard AF ablation technologies without negative effects on procedure durations, success rates, or complication rates. With the use of the technology, abandonment of lead protection for EP staff is possible following transseptal puncture.

Clinical workflow and applicability of electrophysiological cardiovascular magnetic resonance-guided radiofrequency ablation of isthmus-dependent atrial flutter.

Aims: To determine safety and efficacy of electrophysiological cardiovascular magnetic resonance (EP-CMR)-guided radiofrequency (RF) ablation in patients with typical right atrial flutter in a routine clinical setting. Methods and results: Thirty patients with typical right atrial flutter underwent clinically indicated EP-CMR-guided cavotricuspid isthmus ablation. EP-CMR protocols included pre- and post-ablation CMR imaging (whole heart, T2-weighted, and early-/late-gadolinium enhancement) together with electroanatomic mapping of the right atrium. Coronary sinus cannulation time and total ablation procedure duration were used as performance measures to determine the learning experience of the EP-CMR interventionalist and for comparison with conventional, fluoroscopy-guided atrial flutter ablation. Procedural safety and success rates were evaluated at 1 week and 3 months follow-up. Safety and success rates of EP-CMR were similar to conventional flutter ablations (primary success rate, 93% vs. 100%; recurrence rate, 0% vs. 3%, respectively). EP-CMR procedure duration indicated a learning experience (first vs. last six patients, 54.2 ± 23.1 vs. 29.7 ± 20.0 min) and the minimum number of procedures needed to achieve a level of competency was n = 12. An isthmus angle <110° and the presence of pouch-like isthmus anatomy were indicative of significantly prolonged EP-CMR procedure duration. CMR-defined ablation lesion size was not associated with total RF-ablation time or RF-induced maximum temperature. Conclusion: In a routine clinical setting, EP-CMR demonstrated its safety and high efficacy for the treatment of typical right atrial flutter with performance and outcome measures similar to conventional, fluoroscopy-guided flutter ablation. Hence, EP-CMR represents a valid alternative to conventional right atrial flutter ablation.

Acquired Pulmonary Vein Stenosis After Radiofrequency Ablation for Atrial Fibrillation: Single-Center Experience in Catheter Interventional Treatment.

OBJECTIVES: The aim of the present study was to analyze and report a single-center experience with catheter interventional treatment of radiofrequency-induced pulmonary vein stenosis (PVS) following atrial fibrillation (AF) ablation. BACKGROUND: Catheter interventional treatment of radiofrequency-induced PVS following AF ablation remains a challenging field because of a lack of randomized data and treatment guidelines. METHODS: All patients at a single center who underwent catheter interventional treatment for radiofrequency-induced PVS were retrospectively assessed. RESULTS: From January 2004 to September 2017, the total rate of PVS following interventional AF ablation was 0.78% (87 of 11,103). Thirty-nine patients with PVS were treated with 84 catheter interventions: 68 (81%) with percutaneous transluminal balloon angioplasty (PTA) and 16 (19%) with stent implantation. The distribution of stent type was 3 drug-eluting stents (19%) and 13 bare-metal stents (81%). The overall restenosis rate was 53% after PTA versus 19% after stent implantation (p = 0.007) after a median follow-up period of 6 months (interquartile range: 3 to 55 months). The total complication rate for PTA was 10% versus 13% for stenting (p = NS). CONCLUSIONS: This study demonstrates significantly better outcomes in terms of restenosis after stent implantation versus PTA only, with comparable complication rates for these 2 options of interventional treatment of radiofrequency-induced PVS. In summary, despite the lack of randomized studies, the present data and currently available published studies seem to favor stent implantation as a first-line therapy in patients with radiofrequency-induced severe PVS.

Prognostic impact of atrial fibrillation in cardiogenic shock complicating acute myocardial infarction: a substudy of the IABP-SHOCK II trial.

BACKGROUND: Aim of the current study was to analyse the impact of atrial fibrillation (AF) on prognosis in patients with cardiogenic shock (CS) complicating acute myocardial infarction (AMI), which has never been investigated yet. METHODS: The current analysis is a substudy of the IABP-SHOCK II trial. Patients were grouped according to the presence or absence of AF. The primary endpoint was all-cause mortality at 30-day follow-up. Secondary endpoints included all-cause mortality, recurrent myocardial infarction, repeat revascularisation, and stroke at 12 months. RESULTS: AF was documented in 28.2% (n = 169) of all 600 patients initially enrolled in the IABP-SHOCK II trial. There were no significant differences with respect to mortality at 30 days and 12 months between patients with and without AF (p = 0.81, p = 0.74). Similarly, the rates of recurrent myocardial infarction, repeat revascularisation, and stroke did not differ between groups (all p > 0.05). There was no interaction of intraaortic balloon counterpulsation (IABP) and no IABP in patients with or without AF with respect to clinical outcome at 30 days and 12 months (p > 0.05). CONCLUSION: AF is not associated with clinical outcome at 30 days and 12 months in CS complicating AMI.

Ablation of typical atrial flutter using a non-fluoroscopic catheter tracking system vs. conventional fluoroscopy--results from a prospective randomized study.

AIMS: Reduction of radiation exposure using a sensor-based non-fluoroscopic catheter tracking (NFCT) system (MediGuide™, St Jude Medical, Inc.) was recently demonstrated by retrospective comparisons. We aimed to prospectively compare the effects of using NFCT vs. standard fluoroscopy on procedural parameters in patients undergoing radiofrequency ablation of typical atrial flutter. METHODS AND RESULTS: We prospectively randomized 40 patients undergoing cavotricuspid isthmus ablation for typical atrial flutter to either NFCT (n = 20) or conventional fluoroscopy (CONV, n = 20). Procedural parameters such as fluoroscopy time, radiation dose, and procedure duration, as well as periprocedural complications were compared. There were no statistically significant differences in baseline characteristics between the two groups. Bidirectional isthmus block was achieved in all patients. Fluoroscopy time was significantly reduced in the NFCT group {0.3 [inter-quartile range (IQR) 0.2; 0.48] min} when compared with CONV [5.7 (IQR 4.2; 11.5) min] (P < 0.001). This resulted in a significant reduction in radiation dose in patients randomized to NFCT [17.4 (IQR 11; 206.6) cGy cm(2)] vs. the CONV group [418.4 (IQR 277; 812.2) cGy cm(2)] (P < 0.001). There were no significant differences in procedure duration between the NFCT group [49.5 (IQR 37; 65) min] when compared with the CONV group [33.5 (IQR 26.3; 55.5) min] (P = 0.053). No adverse events were recorded. Freedom from atrial flutter at 6 months of follow-up was 19/20 (95%) in the NFCT and 18/20 (90%) in the CONV group (n.s.). CONCLUSION: In this first prospective randomized study, by comparing NFCT with standard fluoroscopy in patients undergoing radiofrequency ablation of typical atrial flutter, NFCT significantly reduced both radiation dose and fluoroscopy time with no effects on procedural duration. These findings support the incorporation of NFCT in routine clinical use.

Early referral for ablation of scar-related ventricular tachycardia is associated with improved acute and long-term outcomes: results from the Heart Center of Leipzig ventricular tachycardia registry.

BACKGROUND: The effects of time to referral for catheter ablation (CA) of scar-related ventricular tachycardia (VT) on acute success, VT recurrence, and cardiac mortality are unclear. METHODS AND RESULTS: We investigated 300 patients after CA of sustained VT. CA was performed within 30 days after the first documented VT in 75 (25%) patients (group 1), between 1 month and 1 year in 84 (28%) patients (group 2), and >1 year after the first VT occurrence in 141 (47%) patients (group 3). The end points were noninducibility of any VT after CA (acute success), VT recurrence and cardiac mortality after 2 years. Acute success was achieved in 66 (88%) patients in group 1, 68 (81%) in group 2, and in 99 (70.2%) in group 3 (P=0.008). During the 2-year follow-up period, VT recurred in 28 (37.3%) patients in group 1, 52 (61.9%) patients in group 2, and 91 (64.5%) patients in group 3 (P<0.0001). Recurrence-free survival was higher in group 1, as compared with group 2 (hazard ratio [HR], 1.85; P=0.009) and group 3 (HR, 2.04; P=0.001). No survival difference was observed between groups 1 and 2 (HR, 0.85; P=0.68) and groups 1 and 3 (HR, 1.13; P=0.73). ß-blocker therapy, VT of ischemic origin, and complete success were associated with VT-free survival. VT recurrence (HR, 1.91; P=0.037) predicted cardiac mortality. CONCLUSIONS: CA of scar-related VT performed within 30 days after the first documented VT was associated with improved acute and long-term success. VT recurrence, but not the early referral for CA, was associated with cardiovascular mortality.