Impact of peri-procedural management of direct oral anticoagulants on pocket haematoma after cardiac electronic device implantation: the StimAOD multicentre prospective study.

AIMS: The study aims to investigate the impact of direct oral anticoagulant (DOAC) management on the incidence of pocket haematoma in patients undergoing pacemaker or implantable cardioverter-defibrillator implantation. METHODS AND RESULTS: All consecutive patients receiving DOAC and undergoing cardiac electronic device implantation were included in a large multicentre prospective observational study (NCT03879473). The primary endpoint was clinically relevant haematoma within 30 days after implantation. Overall, 789 patients were enrolled [median age 80 (IQR 72-85) years old, 36.4% women, median CHA2DS2-VASc score 4 (IQR 0-8)], of which 632 (80.1%) received a pacemaker implantation. Antiplatelet therapy was combined with DOAC in 146 patients (18.5%). Direct oral anticoagulants (DOACs) were interrupted 52 (IQR 37-62) h before the procedure and resumed 31 (IQR 21-47) h later. Ninety-six percent of the patients had at least 12 h DOAC interruption before the procedure, and 78% had at least 12 h DOAC interruption after the procedure. Overall, anticoagulation was interrupted for 72 (IQR 48-96) h. Pre- or post-procedural heparin bridging was used in 8.2% and 3.9%, respectively. Timing of DOAC interruption of resumption was not associated with clinically relevant haematoma. Clinically relevant haematoma occurred in 26 patients (3.3%), and thromboembolic events occurred in 5 patients (0.6%). CONCLUSION: In this large real-life registry where most patients had DOAC interruption, clinically relevant haematoma was rare. Despite DOAC interruption and high CHA2DS2-VASc score, thromboembolic events occurred seldomly, highlighting that bleeding exceeds thromboembolic risk in this peri-procedural period. Future research is needed to identify risk factors for clinically relevant haematoma and meaningfully guide clinicians in optimizing DOAC management.

Long-Term Follow-Up of Patients With Tetralogy of Fallot and Implantable Cardioverter Defibrillator: The DAI-T4F Nationwide Registry.

BACKGROUND: Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart disease, and sudden cardiac death represents an important mode of death in these patients. Data evaluating the implantable cardioverter defibrillator (ICD) in this patient population remain scarce. METHODS: A Nationwide French Registry including all patients with tetralogy of Fallot with an ICD was initiated in 2010 by the French Institute of Health and Medical Research. The primary time to event end point was the time from ICD implantation to first appropriate ICD therapy. Secondary outcomes included ICD-related complications, heart transplantation, and death. Clinical events were centrally adjudicated by a blinded committee. RESULTS: A total of 165 patients (mean age, 42.2±13.3 years, 70.1% males) were included from 40 centers, including 104 (63.0%) in secondary prevention. During a median (interquartile range) follow-up of 6.8 (2.5-11.4) years, 78 (47.3%) patients received at least 1 appropriate ICD therapy. The annual incidence of the primary outcome was 10.5% (7.1% and 12.5% in primary and secondary prevention, respectively; P=0.03). Overall, 71 (43.0%) patients presented with at least 1 ICD complication, including inappropriate shocks in 42 (25.5%) patients and lead dysfunction in 36 (21.8%) patients. Among 61 (37.0%) patients in primary prevention, the annual rate of appropriate ICD therapies was 4.1%, 5.3%, 9.5%, and 13.3% in patients with, respectively, 0, 1, 2, or ≥3 guidelines-recommended risk factors. QRS fragmentation was the only independent predictor of appropriate ICD therapies (hazard ratio, 3.47 [95% CI, 1.19-10.11]), and its integration in a model with current criteria increased the 5-year time-dependent area under the curve from 0.68 to 0.81 (P=0.006). Patients with congestive heart failure or reduced left ventricular ejection fraction had a higher risk of nonarrhythmic death or heart transplantation (hazard ratio, 11.01 [95% CI, 2.96-40.95]). CONCLUSIONS: Patients with tetralogy of Fallot and an ICD experience high rates of appropriate therapies, including those implanted in primary prevention. The considerable long-term burden of ICD-related complications, however, underlines the need for careful candidate selection. A combination of easy-to-use criteria including QRS fragmentation might improve risk stratification. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03837574.

Implantable cardioverter-defibrillator therapy among patients with non-ischaemic vs. ischaemic cardiomyopathy for primary prevention of sudden cardiac death.

Aim: The magnitude of benefit related to implantable cardioverter defibrillator (ICD) therapy for primary prevention of sudden cardiac death (SCD) in non-ischaemic cardiomyopathy (NICM) and ischaemic cardiomyopathy (ICM) has not been evaluated extensively in clinical practice. Methods and results: Of the 5539 consecutive patients enrolled in the multicentre Défibrillateur Automatique Implantable-Prévention Primaire (DAI-PP) study (2002-12), 5485 patients (with information on underlying heart disease) were included in the present analysis: 2181 (39.8%) had NICM and 3304 (60.2%) had ICM. ICM patients were older (63.7 ±10.3 vs. 60.6 ± 12.2 years, P < 0.0001), with a higher ejection fraction [27% (25-30) vs. 25% (20-30), P < 0.0001], narrower QRS (37.3% vs. 21.4% with QRS <120, P < 0.0001), and higher prevalence of sinus rhythm (77.3% vs. 74.0%, P = 0.009). During a mean follow-up of 3.1 ± 2.2 years, 814 patients died, giving a mortality incidence of 48.6 per 1000 person-years [95% confidence interval (CI) 45.2-51.9], higher among ICM patients (52.3, 95% CI 47.8-56.7) than in NICM patients (42.4, 95% CI 37.3-47.6; P = 0.008) (adjusted hazard ratio 1.31, 95% CI 1.06-1.61, P = 0.01). The increase in mortality among ICM patients was mainly due to non-cardiovascular mortality (P = 0.0002), whereas incidences of cardiovascular mortality (including ICD-unresponsive SCD) were similar in the two groups. Incidences of appropriate ICD interventions (anti-tachycardia pacing, shocks) were similar, but inappropriate therapies were more frequent in NICM (7.94 vs. 5.96%; P = 0.005). Conclusion: NICM and ICM patients had a same rate of ICD therapy for primary prevention of SCD in everyday practice. But, ICM patients more often died of a non- cardiovascular cause of death. Clinical Trial Registration: NCT 01992458.

Temporal Trends Over a Decade of Defibrillator Therapy for Primary Prevention in Community Practice.

BACKGROUND: Technology and clinical practice surrounding the use of the primary prevention implantable cardioverter defibrillator (ICD) are in a state of constant evolution. The purpose of the study was to test the hypothesis of significant temporal trends in characteristics and outcomes over a decade of ICD therapy. METHODS: Between 2002 and 2012, 5,539 consecutive patients (age 62.5 ± 11 years, 84.9% male), with ischemic or nonischemic cardiomyopathy, implanted with a primary prevention ICD from 12 centers in France were included. Information on characteristics and outcomes (including causes of death) were evaluated over a median follow-up of 994 days (466-1,667). RESULTS: In addition to a shift in the type of devices implanted with a significant increase in cardiac resynchronization therapy-defibrillator (CRT-D) over time (43.6 to 60.4%, P = 0.0001), an increase in mean age (from 61.5 ± 11.6 to 63.2 ± 10.9 years, P = 0.0016), proportion of nonischemic cardiomyopathy (31.0 to 44.7%, P <0.0001) and women recipients (11.4 to 15.8%, P = 0.004) was observed. A total of 1,181 patients (22.3%) received ≥1 appropriate therapy, inappropriate therapies occurred in 355 patients (6.7%) and 826 patients (15.2%) died, mainly from cardiovascular causes (49.3%). Annual mortality incidence (5.4% to 4.3%, P = 0.05), as well as incidence of appropriate therapy (10.4% to 7.1%, P = 0.0004), significantly decreased over the decade. By contrast, incidence of ICD-related late (>30 days after implant) complications significantly increased (4.6 to 7.6%, P = 0.003). CONCLUSION: Our findings demonstrate significant changes in patterns of use and outcomes in primary prevention ICD over the last decade with reductions in mortality and appropriate therapies, counterbalanced by an increase in complications.

Modification of the Unipolar Atrial Electrogram as a Local Endpoint During Common Atrial Flutter Ablation.

INTRODUCTION: Complete elimination of the negative component of the unipolar atrial electrogram recently proved predictive of lesions transmurality. We prospectively assessed its relevance as a real-time local ablative endpoint for each individual lesion created across the cavotricuspid isthmus (CTI) in order to constitute a line of bidirectionnal block during common atrial flutter (AFL) ablation. METHODS AND RESULTS: Sixty-two consecutive patients underwent common AFL ablation following an electrophysiological approach guided by real-time electrogram modification analysis. In 31 patients (unipolar group), the local ablative endpoint was complete elimination of the negative component of the unipolar atrial electrogram, while the other 31 patients (control group) were treated following our standard approach based on the currently used local ablative endpoint defined by a ≥50% amplitude decrease of the bipolar atrial electrogram. Bidirectional block was achieved in all patients (mean age 67.9 ± 11.5 with 80.6% of men). Mean ablation time (164.3 ± 88.3 seconds vs 332.8 ± 151.5 seconds; P < 0.001) and mean energy delivery (7.5 ± 4.1 kJ vs 14.2 ± 6 kJ; P < 0.001) were significantly shorter in the unipolar group compared to the control group. No statistical differences were seen in procedure time (68.5 ± 22.6 min vs 77.5 ± 20.2 min; P = 0.10). CONCLUSION: Real-time unipolar electrogram modification is a relevant local endpoint during common AFL ablation and leads to a substantial reduction of ablation time and energy delivery compared to a standard ablative approach while displaying a similar short- and long-term success rate.

Higher contact-force values associated with better mid-term outcome of paroxysmal atrial fibrillation ablation using the SmartTouch™ catheter.

AIMS: Real-time measurement of contact force (CF) during catheter ablation of atrial fibrillation (AF) has been recently suggested to potentially impact procedural outcome. However, the role of CF intensity on mid-term results using the SmartTouch™ catheter has not been investigated so far. METHODS AND RESULTS: Pulmonary vein isolation (PVI) using the SmartTouch™ catheter was performed in 100 eligible patients (age 62 ± 8; 79% men) undergoing a first procedure of paroxysmal AF catheter ablation. Continuous CF monitoring during catheter ablation allowed calculation of mean CF per patient. Patients were dichotomized into high CF (≥22 g, upper quartile) and low CF (<22 g, remaining) and enroled in a standardized follow-up programme (after a 3-month blanking period), free from antiarrhythmic therapy, with regular evaluations including 24 h Holter recordings at 1, 3, 6, 9, 12, 18, and 24 months. Atrial fibrillation relapse was defined as any symptomatic or asymptomatic atrial arrhythmia lasting >30 s. The average CF among all procedures was 19.6 ± 3.7 g. Though complete PVI was eventually achieved in all cases in both groups, success using an exclusively anatomical approach was higher in the high CF group (92.0 vs. 72.0%; P = 0.04). During a mean follow-up of 19 ± 5 months, a lower incidence of AF relapse was observed in higher CF patients (4.0 vs. 20.0%; log rank P = 0.04). Pericardial tamponade occurred in one patient in the higher CF group. No thromboembolism or procedure-associated deaths were observed. CONCLUSION: Higher values of CF overall during antral PVI appear to be associated with a higher likelihood of sinus rhythm maintenance without significantly increasing the complication rate.

Contact-force guided radiofrequency vs. second-generation balloon cryotherapy for pulmonary vein isolation in patients with paroxysmal atrial fibrillation-a prospective evaluation.

AIMS: In the setting of paroxysmal atrial fibrillation (AF), there are no available data comparing the mid-term outcome of patients undergoing pulmonary vein isolation (PVI) catheter ablation using contact-force (CF)-guided radiofrequency (RF) vs. second-generation balloon cryotherapy. METHODS AND RESULTS: Prospective single-centre evaluation, carried out from March 2011 to February 2013, comparing CF radiofrequency (Thermocool(®) SmartTouch™, Biosense Webster, Inc.) (CF group) with cryoballoon ablation (Arctic Front Advance™ 28 mm cryoballoon, Medtronic, Inc.) (CB group), in regards to procedural safety and efficacy, as well as recurrence at 12 months. Overall, 150 consecutive patients were enrolled (75 in each group). The characteristics of patients of both the groups were similar (61.2 ± 9.9 years, women 25.3%, mean AF duration 4.1 ± 4.0 years, mean CHA2DS2-VASc score 1.4 ± 1.3, mean HAS-BLED 1.4 ± 0.6). Duration of the procedure was significantly lower in the CF group (110.7 ± 32.5 vs. 134.5 ± 48.3 min, P = 0.001), with a lower duration of fluoroscopy (21.5 ± 8.5 vs. 25.3 ± 9.9 min, P = 0.017) and X-ray exposure (4748 ± 2411 cGy cm² vs. 7734 ± 5361 cGy cm², P = 0.001). In contrast, no significant difference was found regarding significant procedural complication (2.7 vs. 1.3% in CF and CB groups, respectively; P = 0.56), and PVI was eventually achieved in all cases. At 12 months, AF recurrence occurred in 11 patients (14.7%) in the CB group and in 9 patients (12.0%) in the CF group (HR = 1.20 95% CI 0.50-2.90; log rank P = 0.682). CONCLUSIONS: Our preliminary findings suggest that CF-guided radiofrequency and cryotherapy present very similar performances in the setting of paroxysmal AF catheter ablation.

Real-time contact force sensing for pulmonary vein isolation in the setting of paroxysmal atrial fibrillation: procedural and 1-year results.

INTRODUCTION: The additional benefit of contact force (CF) technology during pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (AF) to improve mid-term clinical outcome is unclear. METHODS AND RESULTS: Eligible patients with symptomatic paroxysmal AF were enrolled in this prospective trial, comparing circular antral catheter ablation (guided by Carto 3 System, Biosense Webster) using either a new open-irrigated CF catheter (SmartTouch Thermocool, Biosense Webster) (CF group) or a non-CF open-irrigated catheter (EZ Steer Thermocool, Biosense Webster) (control group). Overall, 30 patients were enrolled in each group, with a standardized 12-month follow-up, free of antiarrhythmic therapy. Demographic, cardiovascular and anatomic characteristics were similar in both groups. Though complete PVI was eventually achieved in all cases in both groups, success using an exclusive anatomic approach was 80.0% in CF group versus 36.7% in control group (P < 0.0001). CF use was associated with significant reductions in fluoroscopy exposure (P < 0.01) and radiofrequency time (P = 0.01). The incidence rates of AF recurrence were 10.5% (95% CI, 1.38-22.4) in the CF group, and 35.9% (95% CI, 12.4-59.4) in the control group (log rank test, P = 0.04). After adjustment on potential confounders, the use of CF catheter was found to be associated with a lower AF recurrence (OR 0.18, 95% CI 0.04-0.94, P = 0.04). CONCLUSION: Our findings suggest a potential benefit of real-time CF sensing technology, in reducing AF recurrence during the first year after PVI.

Long-term follow-up of asymptomatic Brugada patients with inducible ventricular fibrillation under hydroquinidine.

AIMS: To evaluate the long-term efficacy and safety of an electrophysiologically guided therapy, based on a strategy of treatment using hydroquinidine (HQ) among asymptomatic Brugada patients with inducible ventricular fibrillation (VF). METHODS AND RESULTS: In two French reference centres, consecutive asymptomatic type 1 Brugada patients with inducible VF were treated with HQ (600 mg/day, targeting a therapeutic range between 3 and 6 µmol/L) and enroled in a specific follow-up (mean 6.6 ± 3 years), including a second programmed ventricular stimulation (PVS) under HQ. An implantable cardioverter defibrillator (ICD) was eventually implanted in patients inducible under HQ, or during follow-up in case of HQ intolerance, as well as occurrence of arrhythmic events. From a total of 397 Brugada patients, 44 were enroled (47 ± 10 years, 95% male). Of these, 34 (77%) were no more inducible (Group PVS-), and were maintained under HQ alone during a mean follow-up of 6.2 ± 3 years. In this group, an ICD was eventually implanted in four patients (12%), with occurrence of appropriate ICD therapies in one. Among the 10 other patients (22%), who remained inducible and received ICD (Group PVS+), none of them received appropriate therapy during a mean follow-up of 7.7 ± 2 years. The overall annual rate of arrhythmic events was 1.04% (95% confidence interval 0.00-2.21), without any significant difference according to the result of PVS under HQ. One-third of patients experienced device-related complications. CONCLUSION: Our long-term follow-up results emphasize that the rate of arrhythmic events among asymptomatic Brugada patients with inducible VF remains low over time. Our results also suggest that residual inducibility under HQ is of limited value to predict events during follow-up.

Real-time assessment of pulmonary vein disconnection during cryoablation of atrial fibrillation: can it be 'achieved' in almost all cases?

AIM: Real-time assessment of pulmonary vein (PV) disconnection is possible using an inner circular mapping catheter during cryoablation of atrial fibrillation (AF). However, it has been recently demonstrated that such continuous monitoring may only be possible in <50% of PVs. We hypothesized that a stepwise mapping approach, including pacing manoeuvres, could optimize monitoring of real-time PV disconnection during ablation. METHODS AND RESULTS: Single-centre, prospective observational study (NCT01843465) including 34 consecutive eligible patients (128 PVs) undergoing a first procedure of cryoballoon ablation of AF using the Artic Front Advance(®) 28 mm catheter and a 20 mm diameter Achieve(®) catheter (AC) in all cases. Monitoring of real-time entrance block was possible, when AC was maintained in the standard position (distal to the tip of the Artic Front Advance(®) catheter) in 47 (36.7%) PVs. In an additional 63 cases (49.2%), such monitoring was possible after moving AC to a more proximal position and using different torqueing movements. Finally, using supplemental systematic pacing manoeuvres to test exit block, real-time assessment of PV disconnection was possible in 15 (11.7%) more PVs. Overall, real-time assessment of PV disconnection was possible in 97.7% of cases, after a mean duration of 48.6 ± 33.0 s. CONCLUSION: Our results suggest that optimal use of the AC, with a systematic stepwise mapping approach, may dramatically improve the real-time monitoring of PV disconnection during AF cryoablation.

Recurrences of Atrial Fibrillation Despite Durable Pulmonary Vein Isolation: The PARTY-PVI Study.

BACKGROUND: Recurrences of atrial fibrillation (AF) after pulmonary vein isolation (PVI) are mainly due to pulmonary vein reconnection. However, a growing number of patients have AF recurrences despite durable PVI. The optimal ablative strategy for these patients is unknown. We analyzed the impact of current ablation strategies in a large multicenter study. METHODS: Patients undergoing a redo ablation for AF and presenting durable PVI were included. The freedom from atrial arrhythmia after pulmonary vein-based, linear-based, electrogram-based, and trigger-based ablation strategies were compared. RESULTS: Between 2010 and 2020, 367 patients (67% men, 63±10 years, 44% paroxysmal) underwent a redo ablation for AF recurrences despite durable PVI at 39 centers. After durable PVI was confirmed, linear-based ablation was performed in 219 (60%) patients, electrogram-based ablation in 168 (45%) patients, trigger-based ablation in 101 (27%) patients, and pulmonary vein-based ablation in 56 (15%) patients. Seven patients (2%) did not undergo any additional ablation during the redo procedure. After 22±19 months of follow-up, 122 (33%) and 159 (43%) patients had a recurrence of atrial arrhythmia at 12 and 24 months, respectively. No significant difference in arrhythmia-free survival was observed between the different ablation strategies. Left atrial dilatation was the only independent factor associated with arrhythmia-free survival (HR, 1.59 [95% CI, 1.13-2.23]; P=0.006). CONCLUSIONS: In patients with recurrent AF despite durable PVI, no ablation strategy used alone or in combination during the redo procedure appears to be superior in improving arrhythmia-free survival. Left atrial size is a significant predictor of ablation outcome in this population.

Rapid ventricular tachycardia in patients with tetralogy of Fallot and implantable cardioverter-defibrillator: Insights from the DAI-T4F nationwide registry.

BACKGROUND: In repaired tetralogy of Fallot (TOF), little is known about characteristics of patients with rapid ventricular tachycardia (VT). Also, whether patients with a first episode of nonrapid VT may subsequently develop rapid VT or ventricular fibrillation (VF) has not been addressed. OBJECTIVES: The objectives of this study were to compare patients with rapid VT/VF with those with nonrapid VT and to assess the evolution of VT cycle lengths (VTCLs) overtime. METHODS: Data were analyzed from a nationwide registry including all patients with TOF and implantable cardioverter-defibrillator (ICD) since 2000. Patients with ≥1 VT episode with VTCL ≤250 ms (240 beats/min) formed the rapid VT/VF group. RESULTS: Of 144 patients (mean age 42.0 ± 12.7 years; 104 [72%] men), 61 (42%) had at least 1 VT/VF episode, including 28 patients with rapid VT/VF (46%), during a median follow-up of 6.3 years (interquartile range 2.2-10.3 years). Compared with patients in the nonrapid VT group, those in the rapid VT/VF group were significantly younger at ICD implantation (35.2 ± 12.6 years vs 41.5 ± 11.2 years; P = .04), had more frequently a history of cardiac arrest (8 [29%] vs 2 [6%]; P = .02), less frequently a history of atrial arrhythmia (11 [42%] vs 22 [69%]; P = .004), and higher right ventricular ejection fraction (43.3% ± 10.3% vs 36.6% ± 11.2%; P = .04). The median VTCL of VT/VF episodes was 325 ms (interquartile range 235-429 ms). None of the patients with a first documented nonrapid VT episode had rapid VT/VF during follow-up. CONCLUSION: Patients with TOF and rapid VT/VF had distinct clinical characteristics. The relatively low variation of VTCL over time suggests a room for catheter ablation without a backup ICD in selected patients with well-tolerated VT.

Sex Differences in Outcomes of Tetralogy of Fallot Patients With Implantable Cardioverter-Defibrillators.

BACKGROUND: Women with congenital heart disease at high risk for sudden cardiac death have been poorly studied thus far. OBJECTIVES: The aim of this study was to assess sex-related differences in patients with tetralogy of Fallot (TOF) and implantable cardioverter-defibrillators (ICDs). METHODS: Data were analyzed from the DAI-T4F (French National Registry of Patients With Tetralogy of Fallot and Implantable Cardioverter Defibrillator) cohort study, which has prospectively enrolled all patients with TOF with ICDs in France since 2010. Clinical events were centrally adjudicated by a blinded committee. RESULTS: A total of 165 patients (mean age 42.2 ± 13.3 years) were enrolled from 40 centers, including 49 women (29.7%). Among the 9,692 patients with TOF recorded in the national database, the proportion of women with ICDs was estimated to be 1.1% (95% CI: 0.8%-1.5%) vs 2.2% (95% CI: 1.8%-2.6%) in men (P < 0.001). The clinical profiles of patients at implantation, including the number of risk factors for ventricular arrhythmias, were similar between women and men. During a median follow-up period of 6.8 years (IQR: 2.5-11.4 years), 78 patients (47.3%) received at least 1 appropriate ICD therapy, without significant difference in annual incidences between women (12.1%) and men (9.9%) (HR: 1.22; 95% CI: 0.76-1.97; P = 0.40). The risk for overall ICD-related complications was similar in women and men (HR: 1.33; 95% CI: 0.81-2.19; P = 0.30), with 24 women (49.0%) experiencing at least 1 complication. CONCLUSIONS: Our findings suggest that women with TOF at high risk for sudden cardiac death have similar benefit/risk balance from ICD therapy compared with men. Whether ICD therapy is equally offered to at-risk women vs men warrants further evaluation in TOF as well as in other congenital heart disease populations. (French National Registry of Patients With Tetralogy of Fallot and Implantable Cardioverter Defibrillator [DAI-T4F]; NCT03837574).

Impact of Pulmonary Valve Replacement on Ventricular Arrhythmias in Patients With Tetralogy of Fallot and Implantable Cardioverter-Defibrillator.

OBJECTIVES: This study aimed to assess the impact of pulmonary valve replacement (PVR) on ventricular arrhythmias burden in a population of tetralogy of Fallot (TOF) patients with continuous cardiac monitoring by implantable cardioverter-defibrillators (ICDs). BACKGROUND: Sudden cardiac death is a major cause of death in TOF, and right ventricular overload is commonly considered to be a potential trigger for ventricular arrhythmias. METHODS: Data were analyzed from a nationwide French ongoing study (DAI-T4F) including all TOF patients with an ICD since 2000. Survival data with recurrent events were used to compare the burden of appropriate ICD therapies before and after PVR in patients who underwent PVR over the study period. RESULTS: A total of 165 patients (mean age 42.2 ± 13.3 years, 70.1% male) were included from 40 centers. Over a median follow-up period of 6.8 (interquartile range: 2.5 to 11.4) years, 26 patients (15.8%) underwent PVR. Among those patients, 18 (69.2%) experienced at least 1 appropriate ICD therapy. When considering all ICD therapies delivered before (n = 62) and after (n = 16) PVR, the burden of appropriate ICD therapies was significantly lower after PVR (HR: 0.21; 95% confidence interval [CI]: 0.08 to 0.56; p = 0.002). Respective appropriate ICD therapies rates per 100 person-years were 44.0 (95% CI: 35.7 to 52.5) before and 13.2 (95% CI: 7.7 to 20.5) after PVR (p < 0.001). In the overall cohort, PVR before ICD implantation was also independently associated with a lower risk of appropriate ICD therapy in primary prevention patients (HR: 0.29 [95% CI: 0.10 to 0.89]; p = 0.031). CONCLUSIONS: In this cohort of high-risk TOF patients implanted with an ICD, the burden of appropriate ICD therapies was significantly reduced after PVR. While optimal indications and timing for PVR are debated, these findings suggest the importance of considering ventricular arrhythmias in the overall decision-making process. (French National Registry of Patients With Tetralogy of Fallot and Implantable Cardioverter Defibrillator [DAI-T4F]; NCT03837574).

Definition of success criteria for ablation of typical right atrial flutter with a single-catheter approach: A pilot study.

BACKGROUND: The success rate of cavotricuspid isthmus ablation to treat right common flutter is high (up to 95%), but needs bidirectional block confirmation, requiring two or three catheters. AIM: To describe a new pacing technique using a single catheter to ablate and confirm cavotricuspid isthmus block with differential PR interval measurements. METHODS: We included 61 patients from five centres, who were referred for cavotricuspid isthmus ablation. All patients had cavotricuspid isthmus ablation, and the cavotricuspid isthmus block was confirmed by differential pacing using two or three catheters. The new method consisted of measuring the PR interval on the surface electrocardiogram using pacing from the tip of the ablation catheter on the lateral side (lateral delay) and the septal side (coronary sinus ostium) of the cavotricuspid isthmus line (difference=delta PR interval), before and after cavotricuspid isthmus ablation. We analysed the value of the delta PR interval in predicting bidirectional cavotricuspid isthmus block as confirmed by standard methods. RESULTS: Among our patient population (mean age 63±12 years), 39 patients were ablated during sinus rhythm, and 22 during common flutter. Cavotricuspid isthmus block was achieved in all patients but one. Lateral delay and delta PR interval increased significantly after validation of cavotricuspid isthmus block (257±42 vs. 318±50ms and 32±23 vs. 96±22ms, respectively; P<0.0001). A delta PR interval cut-off of ≥70ms had 100% sensitivity and specificity to predict bidirectional cavotricuspid isthmus block. CONCLUSIONS: A single-catheter ablation approach to performing cavotricuspid isthmus line based on surface electrocardiogram PR interval measurement is feasible. After ablation, cavotricuspid isthmus block was systematically obtained when the delta PR interval was>70ms.

Variability in obstructive sleep apnea: Analysis of pacemaker-detected respiratory disturbances.

BACKGROUND: Obstructive sleep apnea (OSA) is associated with several cardiovascular conditions. Some pacemakers feature specific algorithms detecting respiratory cycles and deriving indices well correlated with the identification of polysomnography-confirmed severe OSA. OBJECTIVES: The purposes of this study were to analyze respiratory disturbances measured by a validated algorithm in clinical practice and to describe their variability over time and their association with atrial fibrillation. METHODS: Fifty-eight patients implanted with dual-chamber LivaNova REPLY 200 DR or KORA 100 DR pacemakers measuring a respiratory disturbance index (RDI) were included. An RDI >20 events per hour of sleep is well correlated with severe OSA as determined by polysomnography. Patients with >10% nights with invalid RDI measurements were excluded. RESULTS: The RDI could be measured during 98% of nights. During a mean follow-up of 187 ± 123 days, the individual mean RDI was 19.9 ± 12.7 and was superior to 20 in 24 patients (41%). An RDI >20 events/h in at least 1 night was observed in 52 patients (90%). The mean day-to-day RDI variability in individual patients was 19% ± 21%. Patients with the highest burden of severe OSA (as defined by ≥75% of nights with RDI >20 events/h) were older, had a higher prevalence of hypertension, and were more often implanted for atrioventricular block than patients with lower burden of severe OSA. No RDI burden or cutoff was a predictor of atrial fibrillation occurrence. CONCLUSION: OSA is frequent in patients with a pacemaker and is reliably detected by pacemakers. OSA is highly variable and could probably be best analyzed in terms of burden.

Primary Prevention Implantable Cardioverter Defibrillator (ICD) Therapy in Women-Data From a Multicenter French Registry.

BACKGROUND: There are limited data describing sex specificities regarding implantable cardioverter defibrillators (ICDs) in the real-world European setting. METHODS AND RESULTS: Using a large multicenter cohort of consecutive patients referred for ICD implantation for primary prevention (2002-2012), in ischemic and nonischemic cardiomyopathy, we examined the sex differences in subjects' characteristics and outcomes. Of 5539 patients, only 837 (15.1%) were women and 53.8% received cardiac resynchronization therapy. Compared to men, women presented a significantly higher proportion of nonischemic cardiomyopathy (60.2% versus 36.2%, P<0.001), wider QRS complex width (QRS >120 ms: 74.6% versus 68.5%, P=0.003), higher New York Heart Association functional class (≥III in 54.2%♀ versus 47.8%♂, P=0.014), and lower prevalence of atrial fibrillation (18.7% versus 24.9%, P<0.001). During a 16 786 patient-years follow-up, overall, fewer appropriate therapies were observed in women (hazard ratio=0.59, 95% CI 0.45-0.76; P<0.001). By contrast, no sex-specific interaction was observed for inappropriate shocks (odds ratio ♀=0.84, 95% CI 0.50-1.39, P=0.492), early complications (odds ratio=1.00, 95% CI 0.75-1.32, P=0.992), and all-cause mortality (hazard ratio=0.87 95% CI 0.66-1.15, P=0.324). Analysis of sex-by- cardiac resynchronization therapy interaction shows than female cardiac resynchronization therapy recipients experienced fewer appropriate therapies than men (hazard ratio=0.62, 95% CI 0.50-0.77; P<0.001) and lower mortality (hazard ratio=0.68, 95% CI 0.47-0.97; P=0.034). CONCLUSIONS: In our real-life registry, women account for the minority of ICD recipients and presented with a different clinical profile. Whereas female cardiac resynchronization therapy recipients had a lower incidence of appropriate ICD therapies and all-cause death than their male counterparts, the observed rates of inappropriate shocks and early complications in all ICD recipients were comparable. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov/. Unique identifier: NCT01992458.

Outcome of Primary Prevention Implantable Cardioverter Defibrillator Therapy According to New York Heart Association Functional Classification.

We aimed to assess if the outcome of primary prevention implantable cardioverter defibrillators (ICDs) without cardiac resynchronization therapy is dependent on New York Heart Association (NYHA) class. Among the participants of Défibrillateur Automatique Implantable-Prévention Primaire (DAI-PP; NCT01992458) multicenter cohort study, 155 patients in NYHA class I, 504 in NYHA class II, and 188 in NYHA class III had a QRS width <120 ms and were implanted with an ICD without cardiac resynchronization therapy and, thus, were eligible for the purpose of this analysis. Total and specific mortalities and the incidence of appropriate therapies were assessed for every NYHA. During 2,606 patient-years (3.1 ± 2.1 years), 104 (12.3%) subjects died and 188 (22.2%) experienced appropriate therapies. After adjustment, overall mortality increased with NYHA class (adjusted hazard ratio [HR] 1.63, 95% confidence interval [CI] 1.11 to 2.41, p = 0.014), driven by an increase in cardiovascular death. Conversely, incidence of appropriate ICD intervention was comparable among the 3 NYHA groups (NYHA class I 7.43, NYHA class II 7.91, and NYHA class III 12.10 per 100 patient-years; HR 1.19, 95% CI 0.89 to 1.59, p = 0.231). Incidence of ICD-unresponsive sudden death was very low and also comparable (NYHA class I 0.22, NYHA class II 0.36, and NYHA class III 0.83 per 100 patient-years (HR 6.34, 95% CI 0.32 to 124.49, p = 0.224). No significant differences were observed in the other specific modes of death. In conclusion, although patients in NYHA class III have higher overall mortality, they experience a comparable incidence of appropriate ICD therapies. The low incidence of ICD-unresponsive sudden death in all assessed NYHA classes also supports the efficacy of ICDs, irrespective of NYHA class.