Safety and Long-Term Outcomes of Catheter Ablation of Atrial Fibrillation Using Magnetic Navigation versus Manual Conventional Ablation: A Propensity-Score Analysis.

INTRODUCTION: Whether or not the potential advantages of using a magnetic navigation system (MNS) translate into improved outcomes in patients undergoing atrial fibrillation (AF) ablation is a question that remains unanswered. METHODS AND RESULTS: In this observational registry study, we used propensity-score matching to compare the outcomes of patients with symptomatic drug-refractory AF who underwent catheter ablation using MNS with the outcomes of those who underwent catheter ablation using conventional manual navigation. Among 1,035 eligible patients, 287 patients in each group had similar propensity scores and were included in the analysis. The primary efficacy outcome was the rate of AF relapse after a 3-month blanking period. At a mean follow-up of 2.6 ± 1.5 years, AF ablation with MNS was associated with a similar risk of AF relapse as compared with manual navigation (18.4% per year and 22.3% per year, respectively; hazard ratio 0.81, 95% CI 0.63-1.05; P = 0.108). Major complications occurred in two patients (0.7%) using MNS, and in six patients (2.1%) undergoing manually navigated ablation (P = 0.286). Fluoroscopy times were 21 ± 10 minutes in the manual navigation group, and 12 ± 9 minutes in the MNS group (P < 0.001), whereas total procedure times were 152 ± 52 minutes and 213 ± 58 minutes, respectively (P < 0.001). CONCLUSIONS: In this propensity-score matched comparison, magnetic navigation and conventional manual AF ablations seem to have similar relapse rates and a similar risk of complications. AF ablations with magnetic navigation take longer to perform but expose patients to significantly shorter fluoroscopy times.

Impact of ESC/ACCF/AHA/WHF universal definition of myocardial infarction on mortality at 10 years.

AIMS: Redefinition of myocardial infarction (MI) based on specific cardiac troponins (cTn) was universally accepted in 2007. The new definition has been widely discussed for including a large spectrum of quantitative myocardial necrosis and their clinical implications remain under debate. Our aim was to assess the impact of the universal definition of MI on mortality at 10 years. METHODS AND RESULTS: We studied 676 consecutive patients (Pts) admitted to our intensive cardiac care unit for acute coronary syndrome (ACS) between January 1999 and December 2000. We calculated the relative risk of the total death at 10 years adjusted with the Cox proportional hazards model, between the presence and absence of MI following different definitions: (1), typical symptoms and persistent ST-segment elevation or left bundle branch block (ST-segment elevation definition); (2), typical symptoms and CK-MB activity rise and/or fall >ULN (old definition); and (3), typical symptoms and cTn I rise and/or fall >99th percentile (universal definition). The total mortality at 10 years was 23.8%. The proportion of Pts with AMI was 33.6% for ST-segment elevation definition, 55.8% for old definition, and 70.1% for universal definition. The adjusted hazard ratio of death at 10 years between the presence and absence of AMI was 0.71 (95% confidence interval (CI): 0.46-1.08; P = 0.11) for ST-segment elevation definition, 0.84 (95% CI: 0.55-1.27; P = 0.40) for old definition, and 1.58 (95% CI: 1.07-2.40; P = 0.03) for universal definition. Patients submitted to myocardial revascularization during the initial hospital stay (72%) presented a significantly lower mortality at 10 years, compared with patients not revascularized (adjusted hazard ratio: 0.63, 95% CI: 0.44-0.91; P = 0.014). CONCLUSIONS: In a population with the entire spectrum of ACSs, the universal definition of MI increased this diagnosis by one-quarter and was an independent predictor of mortality at 10 years. Furthermore, myocardial revascularization was associated with a significantly lower mortality at 10 years.

Sequencing and titrating approach of therapy in heart failure with reduced ejection fraction following the 2021 European Society of Cardiology guidelines: an international cardiology survey.

AIMS: In symptomatic patients with heart failure and reduced ejection fraction (HFrEF), recent international guidelines recommend initiating four major therapeutic classes rather than sequential initiation. It remains unclear how this change in guidelines is perceived by practicing cardiologists versus heart failure (HF) specialists. METHODS AND RESULTS: An independent academic web-based survey was designed by a group of HF specialists and posted by email and through various social networks to a broad community of cardiologists worldwide 1 year after the publication of the latest European HF guidelines. Overall, 615 cardiologists (38 [32-47] years old, 63% male) completed the survey, of which 58% were working in a university hospital and 26% were HF specialists. The threshold to define HFrEF was ≤40% for 61% of the physicians. Preferred drug prescription for the sequential approach was angiotensin-converting enzyme inhibitors or angiotensin receptor-neprilysin inhibitors first (74%), beta-blockers second (55%), mineralocorticoid receptor antagonists third (52%), and sodium-glucose cotransporter 2 inhibitors (53%) fourth. Eighty-four percent of participants felt that starting all four classes was feasible within the initial hospitalization, and 58% felt that titration is less important than introducing a new class. Age, status in training, and specialization in HF field were the principal characteristics that significantly impacted the answers. CONCLUSION: In a broad international cardiology community, the 'historical approach' to HFrEF therapies remains the preferred sequencing approach. However, accelerated introduction and uptitration are also major treatment goals. Strategy trials in treatment guidance are needed to further change practices.

Impact of Contact Force-Sensing Catheters on Fluoroscopy Time in Interventional Electrophysiology: A European Survey.

This multicenter European survey systematically evaluated the impact of using contact force-sensing catheters (CFSCs) on fluoroscopy and procedure time in interventional electrophysiology. Data from 25 participating centers were collected and analyzed, also considering important confounders. With the use of CFSCs, fluoroscopy time was reduced for right- and left-sided atrial ablations (median −6.4 to −9.6 min, p < 0.001 for both groups), whereas no such effect could be found for ventricular ablations. Moreover, the use of CFSCs was associated with an increase in procedure time for right-sided atrial and ventricular ablations (median +26.0 and +44.0 min, respectively, p < 0.001 for both groups), but not for left-sided atrial ablations. These findings were confirmed independent of career level and operator volume, except for very highly experienced electrophysiologists, in whom the effect was blunted. In the subset of pulmonary vein isolations (PVIs), CFSCs were shown to reduce both fluoroscopy and procedure time. In conclusion, the use of CFSCs was associated with a reduced fluoroscopy time for atrial ablations and an increased procedure time for right atrial and ventricular ablations. These effects were virtually independent of the operator experience and caseload. When considering only PVIs as an important subset, CFSCs were shown to reduce both fluoroscopy and procedure time.

A new electrophysiologic triad for identification and localization of the critical isthmus in atrial flutter.

INTRODUCTION: Atypical atrial flutter (AFL) is a supraventricular arrhythmia that can be treated with catheter ablation. However, this strategy yields suboptimal results and the best approach is yet to be defined. Carto® electroanatomical mapping (EAM) version 7 displays a histogram of the local activation times (LAT) of the tachycardia cycle length (TCL), in addition to activation and voltage maps. Using these EAM tools, the study aimed to assess the ability of an electrophysiologic triad to identify and localize the critical isthmus in AFL. METHODS: Retrospective analysis using Carto® EAM of a single center registry of individuals who underwent left AFL ablation over one year. Subjects with non-left AFL, no high-density EAM, under 2000 points or no left atrium wall or structure mapping were excluded. Sites where arrhythmia is terminated via ablation were compared to an electrophysiologic triad comprising areas of low-voltage (0.05 to 0.3 mV), deep histogram valleys (LAT-valleys) with less than 20% density points relative to the highest density zone and a prolonged LAT-valley duration, which included 10% or more of the TCL. The longest LAT-valley was designated as the primary valley, while additional valleys were named as secondary. RESULTS: A total of nine subjects (six men, median age 75, interquartile range 71-76 years) were included. All patients presented with left AFL and 66% had a history of ablation for atrial fibrillation and/or flutter. The median TCL and collected points were 254 ms (220-290) and 3300 (IQR 2410-3926) points, respectively. All individuals with AFL presented with at least one LAT-valley on the analyzed histograms, which corresponded to heterogeneous low voltage areas (0.05 to 0.3 mV) and affected more than 10% of TCL. Six of the nine patients presented with a secondary LAT-valley. All arrhythmias were terminated successfully following radiofrequency ablation at the primary LAT-valley location. After a minimum three-month follow-up all patients remained in sinus rhythm. CONCLUSION: An electrophysiologic triad identified the critical isthmus in AFL for all patients. Further studies are needed to assess the usefulness of this algorithm in improving catheter ablation outcomes.

Implantable Cardioverter-Defibrillators in Trials of Drug Therapy for Heart Failure: A Systematic Review and Meta-Analysis.

BACKGROUND Medical therapy for heart failure with reduced ejection fraction evolved since trials validated the use of implantable cardioverter-defibrillators (ICDs). We sought to evaluate the performance of ICDs in reducing mortality in the era of modern medical therapy by means of a systematic review and meta-analysis of contemporary randomized clinical trials of drug therapy for heart failure with reduced ejection fraction. METHODS AND RESULTS We systematically identified randomized clinical trials that evaluated drug therapy in patients with heart failure with reduced ejection fraction that reported mortality. Studies that enrolled <1000 patients, patients with left ventricular ejection fraction >40%, or patients in the acute phase of heart failure and study treatment with devices were excluded. We identified 8 randomized clinical trials, including 31 701 patients of whom 3631 (11.5%) had an ICD. ICDs were associated with a lower risk of all-cause mortality (relative risk [RR], 0.85; 95% CI, 0.78-0.94) and sudden cardiac death (RR, 0.49; 95% CI, 0.40-0.61). Results were consistent among studies published before and after 2010. In meta-regression analysis, the proportion of nonischemic etiology did not affect the associated benefit of ICD. CONCLUSIONS In our meta-analysis of contemporary randomized trials of drug therapy for heart failure with reduced ejection fraction, the rate of ICD use was low and associated with a decreased risk in both all-cause mortality and sudden cardiac death. This benefit was still present in trials with new medical therapy.

Very long-term outcomes after a single catheter ablation procedure for the treatment of atrial fibrillation-the protective role of antiarrhythmic drug therapy.

BACKGROUND: Pulmonary vein isolation (PVI) is the cornerstone of AF ablation, but its long-term clinical outcomes, predictors of relapse, and optimal pharmacological treatment remain controversial. OBJECTIVE: The objectives of this paper were to (1) assess very long-term AF recurrence, (2) identify predictors of relapse, and (3) evaluate the impact of continued antiarrhythmic drug (AAD) treatment after ablation. METHODS: Multicenter observational registry including all consecutive patients with drug-resistant AF who underwent a first PVI between 2006 and 2008 (n = 253 (age 55 years (IQR 48-63)), 80% males, 64% with paroxysmal AF. Endpoint was AF/AT/AFL relapse after a 3-month blanking period. Predictors and protective factors of AF relapse were assessed with multivariate Cox regression. RESULTS: A total of 144 patients (57%) relapsed over a median 5-year (IQR 2-9) follow-up-annual relapse rate of 10%/year. Female sex (aHR 1.526, 95% CI 1.037-2.246, P = 0.032), non-paroxysmal AF (aHR 1.410, 95% CI 1.000-1.987, P = 0.050), and LA volume/BSA (aHR 1.012, 95% CI 1.003-1.021, P = 0.008) were identified as independent predictors of relapse. A total of 139 patients (55%) continued AAD (55% on amiodarone) after blanking period. One-year overall PVI success rate of patients under AAD was 86 vs 76% with no AAD (P < 0.001)-annual relapse rates were 8%/year vs 14%/year (P < 0.001), respectively. AAD was associated with a long-term reduction in AF relapse (aHR 0.673, 95% CI 0.509-0.904 P = 0.004). CONCLUSION: Half the patients remained free from AF 5 years after a single procedure. Female sex, non-paroxysmal AF, and LA volume/BSA independently predicted recurrence, whereas continuing AAD after the 3-month blanking period reduced relapse. In a multicenter registry of AF patients undergoing a first PVI, 57% relapsed over a median 5-year follow-up. Female sex, non-paroxysmal AF and LA volume/BSA were identified as independent predictors of relapse. Maintaining AAD therapy after the blanking period was associated with a long-term reduction in AF relapse.

Impact of prophylactic cavotricuspid isthmus ablation in atrial fibrillation recurrence after a first pulmonary vein isolation procedure.

INTRODUCTION: PVI is a well-established therapy for patients with drug refractory atrial fibrillation (AF). However, it remains unclear whether prophylactic cavotricuspid isthmus (CTI) ablation at the time of PVI improves long-term freedom from AF. OBJECTIVE: To compare the outcomes of patients who underwent PVI alone vs. PVI + prophylactic CTI ablation. METHODS: Propensity score (PS) matching analysis based on a registry dataset of 1931 consecutive patients who underwent a first AF catheter ablation. After excluding those with documented/inducible atrial flutter (n = 233), 1698 individuals were available for matching. Following adjustment for age, gender, body mass index (BMI), hypertension, smoking, diabetes, LA volume, type of AF, and type of navigation (magnetic vs. manual), PS matched 411 patients who underwent PVI + CTI ablation with 411 receiving PVI alone. RESULTS: PS analysis yielded a study population of 822 matched patients (58 ±â€¯11 years, 69% males, 64% with paroxysmal AF). Over a median 2 years follow-up period there were 278 AF recurrences (34%). Survival free of AF (Log rank p = .965) and annual relapse rates were similar in the two groups - 10.9%/year vs 10.1%/year (PVI vs PVI + CTI, respectively, p = .97). CTI ablation remained unassociated with AF-free survival (HR 1.09, 95%CI: 0.84-1.41, p = .54) after Cox regression adjustment for age, sex, type of AF, LA volume, hypertension, diabetes, BMI and center. Female gender, current smoking, indexed LA volume and non-paroxysmal AF were identified as independent predictors of relapse after matching. CONCLUSIONS: Prophylactic CTI ablation at the time of a first PVI does not seem to improve long-term freedom from AF.

Adenosine-guided pulmonary vein isolation versus conventional pulmonary vein isolation in patients undergoing atrial fibrillation ablation: An updated meta-analysis.

BACKGROUND: Recurrent atrial fibrillation episodes following pulmonary vein isolation (PVI) are frequently due to reconnection of PVs. Adenosine can unmask dormant conduction, leading to additional ablation to improve AF-free survival. We performed a meta-analysis of the literature to assess the role of adenosine testing in patients undergoing atrial fibrillation (AF) ablation. METHODS: PubMed, EMBASE, and Cochrane databases were searched through until December 2015 for studies reporting on the role of adenosine guided-PVI versus conventional PVI in AF ablation. RESULTS: Eleven studies including 4099 patients undergoing AF ablation were identified to assess the impact of adenosine testing. Mean age of the population was 61±3years: 25% female, 70% with paroxysmal AF. Follow up period of 12.5±5.1months. A significant benefit was observed in the studies published before 2013 (OR=1.75; 95%CI 1.32-2.33, p<0.001, I2=11%), retrospective (OR=2.05; 95%CI 1.47-2.86, p<0.001, I2=0%) and single-centre studies (OR=1.58; 95%CI 1.19-2.10, p=0.002, I2=30%). However, analysis of studies published since 2013 (OR=1.41; 95% CI 0.87-2.29, p=0.17, I2=75%) does not support any benefit from an adenosine-guided strategy. Similar findings were observed by pooling prospective case-control (OR=1.39; 95%CI 0.93-2.07, p=0.11, I2=75%), and prospective randomized controlled studies (OR=1.62; 95%CI 0.81-3.24, p=0.17, I2=86%). Part of the observed high heterogeneity can be explained by parameters such as dormant PVs percentage, use of new technology, improvement of center/operator experience, patients' characteristics including gender, age, and AF type. CONCLUSIONS: Pooling of contemporary data from high quality prospective case-control & prospective randomized controlled studies fails to show the benefit of adenosine-guided strategy to improve AF ablation outcomes.

Left atrial volume is more important than the type of atrial fibrillation in predicting the long-term success of catheter ablation.

BACKGROUND: The type of atrial fibrillation (AF) is the sole prognostic factor that affects the level of recommendation for catheter ablation in the current guidelines. Despite being recognized as a predictor of recurrence, relatively little emphasis is given to left atrium (LA) size. The aim of this study was to assess the relative importance of LA volume and type of AF as predictors of outcome after PVI. METHODS: We assessed 809 consecutive patients with symptomatic drug-refractory AF (584 male, mean age 57 ± 11 years) undergoing 905 percutaneous PVI procedures in two centers. LA volume was assessed by cardiac CT and/or electroanatomical mapping prior to AF ablation. The study endpoint was symptomatic and/or documented AF recurrence. RESULTS: The majority of patients (73.2%, n=592) had paroxysmal AF. The mean indexed LA volume was 55 ± 20 ml/m(2). During a follow-up of 2.4 ± 1.7 years, there were 280 recurrences. The relapse rate of patients with paroxysmal AF in the highest tertile of LA volume was higher than the relapse rate of patients with non-paroxysmal AF in the lowest tertile (20.0% vs. 10.9% per person-year, respectively, p=0.041). LA volume (HR 1.16 for each 10 ml/m(2), 95% CI 1.09-1.23, p<0.001), female gender (HR 1.55, 95% CI 1.19-2.03, p=0.001), and non-paroxysmal AF (HR 1.31, 95% CI 1.01-1.69, p=0.039) were the only independent predictors of AF recurrence. Split-sample cross-validation resampling confirmed LA volume as the strongest predictor of relapse after PVI. CONCLUSION: Left atrial volume seems to be more important than the type of atrial fibrillation in predicting the long-term success of pulmonary vein isolation.