Predictors of recurrence after durable pulmonary vein isolation for paroxysmal atrial fibrillation.

AIMS: Catheter ablation of paroxysmal atrial fibrillation (AF) reduces AF recurrence, AF burden, and improves quality of life. Data on clinical and procedural predictors of arrhythmia recurrence are scarce and are flawed by the high rate of pulmonary vein reconnection evidenced during repeat procedures after pulmonary vein isolation (PVI). In this study, we identified clinical and procedural predictors for AF recurrence 1 year after CLOSE-guided PVI, as this strategy has been associated with an increased PVI durability. METHODS AND RESULTS: Patients with paroxysmal AF, who received CLOSE-guided PVI and who participated in a prospective trial in our centre, were included in this study. Uni- and multivariate models were plotted to find clinical and procedural predictors for AF recurrence within 1 year. Three hundred twenty-five patients with a mean age of 63 years (CHA2DS2VASc 1 [1-3], left atrium diameter 41 ± 6 mm) were included. About 60.9% were male individuals. After 1 year, AF recurrence occurred in 10.5% of patients. In a binary logistic regression analysis, the diagnosis-to-ablation time (DAT) was found to be the strongest predictor of AF recurrence (P = 0.011). Diagnosis-to-ablation time ≥1 year was associated with a nearly two-fold increased risk for developing AF recurrence. CONCLUSION: The DAT is the most important predictor of arrhythmia recurrence in low-risk patients treated with durable pulmonary vein isolation for paroxysmal AF. Whether reducing the DAT could improve long-term outcomes should be investigated in another trial.

Evaluation of higher power delivery during RF pulmonary vein isolation using optimized and contiguous lesions.

AIMS: "CLOSE"-guided pulmonary vein isolation (PVI) is based on contiguous (≤6 mm) and optimized radiofrequency (RF) ablation lesions (ablation index [AI] ≥ 400 posteriorly and ≥ 550 anteriorly]. However, the optimal RF power to reach the desired AI is unknown. Therefore we evaluated the efficiency of an ablation strategy using higher power (40 W) during a first "CLOSE"-guided PVI. METHODS: Eighty consecutive patients undergoing "CLOSE"-guided PVI for symptomatic paroxysmal atrial fibrillation were ablated with 40 W (group A). Results were compared with 105 consecutive patients enrolled in the "CLOSE to CURE"-study and were ablated using the same protocol with 35 W (group B). RESULTS: In group A, ablation was associated with shorter ablation procedure time (91 vs 111 minutes; P < .001), shorter fluoroscopy time (5 vs 11 minutes; P < .001), shorter PVI time (48 vs 64 minutes; P < .001), shorter RF time (20 vs 28 minutes; P < .001), lower RF time per application (22 vs 29 seconds; P < .001), less RF applications (52 vs 58; P < .001), and less catheter dislocations (1 vs 2; P = .002). The impedance drop (12 vs 13 Ω; P = .192), first-pass isolation rate (99% vs 93%; P = .141) and acute reconnection rate (6% vs 4%; P > .733) were similar in both groups (groups A and B, respectively). No complications occurred. In group A, a gastroscopy-performed in five patients with esophageal temperature rise more than 42°C-did not reveal any esophageal lesion. Postprocedural recurrence of atrial tachyarrhythmia at 1 year was not significantly different between both groups. CONCLUSIONS: Using the "CLOSE"-protocol, increased power increases the efficiency of PVI without compromising patients' safety.

Leveraging User Experience to Improve Video Consultations in a Cardiology Practice During the COVID-19 Pandemic: Initial Insights.

During the coronavirus disease (COVID-19) pandemic, cardiologists have attempted to minimize risks to their patients by using telehealth to provide continuing care. Rapid implementation of video consultations in outpatient clinics for patients with heart disease can be challenging. We employed a design thinking tool called a customer journey to explore challenges and opportunities when using video communication software in the cardiology department of a regional hospital. Interviews were conducted with 5 patients with implanted devices, a nurse, an information technology manager and two cardiologists. Three lessons were identified based on these challenges and opportunities. Attention should be given to the ease of use of the technology, the meeting features, and the establishment of the connection between the cardiologist and the patient. Further, facilitating the role of an assistant (or virtual assistant) with the video consultation software who can manage the telehealth process may improve the success of video consultations. Employing design thinking to implement video consultations in cardiology and to further implement telehealth is crucial to build a resilient health care system that can address urgent needs beyond the COVID-19 pandemic.

Identification of repetitive atrial activation patterns in persistent atrial fibrillation by direct contact high-density electrogram mapping.

INTRODUCTION: Recent studies have characterized drivers in persistent atrial fibrillation using automated algorithm detection with panoramic endocardial mapping by means of basket catheters. We aimed to identify repetitive atrial activation patterns (RAAPs) during ongoing atrial fibrillation (AF) based upon automated annotation of unipolar electrograms (EGMs) recorded with a high-density regional endocardial contact mapping catheter. METHODS: In 14 persistent AF patients, high-resolution EGMs were recorded for 30 seconds at sequential PentaRay (Biosense Inc) positions covering the entire biatrial surface. All recordings were reviewed off-line with dedicated software allowing automated annotation of the local activation time of the unipolar fibrillatory EGMs (CARTOFINDER; Biosense Inc). RAAPs were defined as a consistent activation pattern (for ≥3 consecutive beats) of either focal activity with centrifugal spread (RAAPfocal ) or rotational activity across the PentaRay splines spanning the AF cycle length (RAAProtational ). RESULTS: A total of 498 PentaRay recordings were analyzed (35.6 ± 7.6 per patient). The number of PentaRay recordings displaying RAAP was 9.8 ± 3.1 per patient (range = 3-15), of which 2.4 ± 2.4 RAAProtational (range = 0-7), and 7.4 ± 4.4 RAAPfocal (range = 1-13). 77% of RAAPs portrayed focal firing. The median number of repetitions per 30 second recording was 11 (range = 3-225) per recording. RAAPs were observed both in the right atrium (RA) (35%) and left atrium (LA) (65%), with the majority being near the left PVs/appendage (35% of all RAAPs) and the superior vena cava/right appendage (23% of all RAAPs). CONCLUSION: High-resolution, sequential endocardial EGM-based mapping allows identification of RAAPs in persistent AF. In our series, focal firing was the most frequently observed pattern.

Evaluation of a simple technique aiming at optimizing point-by-point isolation of the left pulmonary veins: a randomized study.

AIMS: We sought to evaluate the efficacy and the safety of a simple technique for stabilizing the ablation catheter during anterior pulmonary vein (PV) encirclement in patients ablated for paroxysmal atrial fibrillation. This consisted of bending the ablation catheter in the left atrium, creating a loop that was cautiously advanced together with the long sheath at the ostium and then within the left superior PV. The curve was then progressively released to reach a stable contact with the anterior part of the left PVs. METHODS AND RESULTS: Eighty consecutive patients (age 64 ± 11 years, left atrial diameter 43 ± 8 mm) undergoing 'CLOSE'-guided PV isolation were prospectively randomized into two groups depending on whether the loop technique was used or not. When using the loop technique, the encirclement of the left PVs was shorter [20 min (interquartile range, IQR 17-24) vs. 26 min (IQR 18-33), P < 0.01] with a high rate of first pass isolation [(100%) vs. (97%), P = 0.9] and adenosine proof isolation [(93%) vs. (95%), P = 0.67]. Most specifically, at the anterior part of the left PVs, there were less dislocations [0 (IQR 0-0) vs. 1 (IQR 0-4), P < 0.001], radiofrequency duration was shorter (272 ± 85 s vs. 378 ± 122 s, P < 0.001), force-time integral was higher [524 gs (IQR 427-687) vs. 398 gs (IQR 354-451), P < 0.001], average contact force was higher [20 g (IQR 13-27) vs. 11g (IQR 9-16), P < 0.001], and impedance drop was higher [12 Ω (IQR 9-19) vs. 10 Ω (IQR 7-14), P < 0.001]. CONCLUSION: This study describes a simple technique to facilitate catheter stability at the anterior part of the left PVs, resulting in more efficient left PV encirclement without compromising safety.

Failure to detect life-threatening arrhythmias in ICDs using single-chamber detection criteria.

BACKGROUND: There are anecdotal reports of sudden death despite a functional implantable cardioverter defibrillator (ICD). We sought to describe scenarios leading to fatal or near-fatal outcome due to inappropriately inhibited ICD therapy in devices programmed with single-chamber detection criteria. METHODS: Programmed settings, episode lists, and intracardiac electrograms from 24 patients with a life-threatening event (n = 12) or fatal outcome (n = 12) related to failed ventricular arrhythmia detection were used to clarify the underlying scenario. RESULTS: Fifty episodes of failed ventricular arrhythmia detection were identified and categorized into six scenarios: (1) spontaneous ventricular tachycardia (VT) or ventricular fibrillation (VF) with a rate below the detection limits, (2) misclassification of polymorphic VT (PVT) or VF as supraventricular tachycardia (SVT), (3) misclassification of VT/VF as cluster of nonsustained VT episodes, (4) misclassification of monomorphic VT (MVT) as SVT, (5) inappropriate shock abortion, and (6) false termination detection. These scenarios occurred respectively 6, 9, 3, 9, 8, and 15 times. In 9/9 (100%) patients with PVT/VF classified as SVT, rate stability was active for rates ranging from 222 to 250 beats/min. MVT detected as SVT was due to the sudden onset criterion in 7/9 (78%) patients and twice a consequence of the rate stability criterion active for rates ranging from 200 to 250 beats/min. CONCLUSION: We describe six scenarios leading to failure of ventricular arrhythmia detection in a single-chamber detection setting withholding life-saving therapy. These scenarios are more likely to occur with high-rate programming and long detection times, especially if combined with rate stability and sudden onset.

PulmOnary vein isolation With vs. without continued antiarrhythmic Drug trEatment in subjects with Recurrent Atrial Fibrillation (POWDER AF): results from a multicentre randomized trial.

Aims: Catheter ablation is indicated in patients with symptomatic paroxysmal atrial fibrillation (AF) resistant to antiarrhythmic drug therapy (ADT). We investigated whether continued use of previously ineffective ADT beyond the post-ablation blanking period reduces recurrence of atrial tachyarrhythmia within the 1st year after ablation. Methods and results: This was a multicentre, randomized controlled study in patients undergoing contact force-guided pulmonary vein isolation (PVI) for paroxysmal AF in whom previously ineffective ADT was continued during a blanking period of 3 months. If free of AF at the end of the blanking period, patients were randomly assigned in the ratio of 1:1 to continue ADT (ADT ON group, n = 77) or discontinue ADT (ADT OFF group, n = 76). Patients were followed up until 1 year after PVI, with clinical visits, Holter monitoring, and quality-of-life (QOL) questionnaires at 6 and 12 months post-procedure. Analysis of the primary endpoint (any documented atrial tachyarrhythmia lasting >30 s) was performed according to the modified intention-to-treat principle. Secondary endpoints included repeat ablation, unscheduled visits, and QOL score. Baseline clinical characteristics and initial ablation procedure characteristics were comparable between both groups. Three patients were lost to follow-up in each arm. The primary endpoint was observed in 2 of 74 (2.7%) patients in the ADT ON group vs. 16 of 73 (21.9%) patients in the ADT OFF group (P < 0.001). The ADT ON group had a lower rate of repeat ablation [1.4% vs. 19.2%, hazard ratio (HR) = 0.053; 95% confidence interval (CI) 0.007-0.399; P < 0.01) and less unscheduled arrhythmia-related health care visits (2.7% vs. 20.5%, HR = 0.055, 95% CI 0.007-0.410; P < 0.01). Quality-of-life scores were similar in both groups. Conclusion: In patients free of AF at the end of 3 months of post-ablation blanking period, continued use of previously ineffective ADT significantly reduces the recurrence of atrial tachyarrhythmia in the 1st year after PVI.

Clinical assessment and comparison of annotation algorithms in high-density mapping of regular atrial tachycardias.

BACKGROUND: High-density automated mapping of regular atrial tachycardias (ATs) requires accurate assessment of local activation times (LATs). OBJECTIVE: To evaluate high-density mapping of ATs and compare the accuracy of different automated LAT annotation algorithms. METHODS: Fifteen patients underwent AT ablation guided by the automated ConfiDENSEۛ high-density mapping module (Carto 3 v4) allowing manual reannotation (edited maps). For each AT, unedited automated maps were reconstructed offline by three algorithms: maximum unipolar slope (LATSlope ), bipolar peak (LATPeak ), and a new hybrid annotation algorithm (LATHybrid ). Five blinded experts were asked to define the (1) tachycardia mechanism, (2) ablation target, and (3) level of difficulty of these unedited maps. RESULTS: Twenty-one ATs (cycle length 300 ± 46 ms, activation points 955 ± 421) were successfully ablated using LATHybrid guided ablation with manual editing in a small number of points. At 6 months, 14 (93%) of the patients were free of AT recurrences. Unedited LATHybrid maps showed the highest accuracy in defining the tachycardia mechanism (LATHybrid : 49% vs. LATPeak : 27% vs. LATSlope : 28%, P < 0.001) and ablation target (LATHybrid : 65% vs. LATPeak : 39% vs. LATSlope : 31%, P < 0.001). Overall, LATHybrid -annotated maps were graded as "easier to interpret" by the experts (difficulty score 2.3 ± 0.9) versus LATPeak (2.8 ± 1) and LATSlope (3.2 ± 0.8) (P < 0.001). Only 12% of the LATHybrid maps were annotated as uninterpretable compared to 31% of LATSlope and 45% of the LATPeak maps (P < 0.001). CONCLUSION: Automated LATHybrid annotation allows better and easier recognition of the tachycardia mechanism compared to automated LATPeak and LATSlope algorithms, although fully automated mapping still requires further improvements.

Improving procedural and one-year outcome after contact force-guided pulmonary vein isolation: the role of interlesion distance, ablation index, and contact force variability in the 'CLOSE'-protocol.

Aims: We have recently shown that a contact force (CF)-guided ablation protocol respecting region-specific criteria of lesion contiguity and lesion depth ('CLOSE' protocol) is associated with high incidence of acute durable pulmonary vein (PV) isolation (PVI) and a high single-procedure arrhythmia-free survival at 1 year. In the present study, we compared efficiency, safety, and efficacy of 'CLOSE'-guided PVI to conventional CF-guided PVI (CONV-CF). Methods and results: Fifty consecutive paroxysmal atrial fibrillation (AF) patients underwent PV encircling using a CF-sensing catheter targeting an interlesion distance (ILD) ≤6 mm and ablation index (AI) ≥400 and ≥550 at posterior and anterior wall ('CLOSE' group). Results were compared to the last 50 patients undergoing 'CONV-CF'. All patients underwent adenosine testing after PVI. Arrhythmia recurrence was defined as any atrial tachyarrhythmia (ATA) >30 s on Holter at 3, 6, and 12 months. Clinical characteristics did not differ. Contact force variability was comparable in between both groups (proportion of applications with intermittent contact 2% in 'CLOSE' vs. 1% in CONV-CF, P = 0.67). In the 'CLOSE' group, procedure time and radiofrequency (RF) time per circle were shorter (respectively 149 ± 33 min vs. 192 ± 42 min, P < 0.0001 and 18 ± 4 min vs 28 ± 7.5 min, P < 0.0001) and incidence of adenosine-proof isolation was higher (97% vs. 82%, P < 0.001). No complications were observed in the 'CLOSE' group, one tamponade in the 'CONV-CF' group. At 12 months, single-procedure freedom from ATA was 94% in 'CLOSE' vs. 80% in 'CONV-CF' group (P < 0.05). In both groups, the majority of reconnections at repeat were associated with either ILD > 6 mm and/or AI < 400/550 (100% vs. 83%, P = 0.99). Conclusion: 'CLOSE'-guided PVI improves procedural and 1 year outcome in CF-guided PVI while shortening procedure time. Improvement cannot be explained by differences in CF variability and is most likely due to the strict application of criteria for contiguity and ablation index. A randomized controlled trial is needed to exclude the possible contribution of a learning curve.

Evaluation of left atrial linear ablation using contiguous and optimized radiofrequency lesions: the ALINE study.

Aims: Achieving block across linear lesions is challenging. We prospectively evaluated radiofrequency (RF) linear ablation at the roof and mitral isthmus (MI) using point-by-point contiguous and optimized RF lesions. Methods and results: Forty-one consecutive patients with symptomatic persistent AF underwent stepwise contact force (CF)-guided catheter ablation during ongoing AF. A single linear set of RF lesions was delivered at the roof and posterior MI according to the 'Atrial LINEar' (ALINE) criteria, i.e. point-by-point RF delivery (up to 35 W) respecting strict criteria of contiguity (inter-lesion distance ≤ 6 mm) and indirect lesion depth assessment (ablation index ≥550). We assessed the incidence of bidirectional block across both lines only after restoration of sinus rhythm. After a median RF time of 7 min [interquartile range (IQR) 5-9], first-pass block across roof lines was observed in 38 of 41 (93%) patients. Final bidirectional roof block was achieved in 40 of 41 (98%) patients. First-pass block was observed in 8 of 35 (23%) MI lines, after a median RF time of 8 min (IQR 7-12). Additional endo- and epicardial (54% of patients) RF applications resulted in final bidirectional MI block in 28 of 35 (80%) patients. During a median follow-up of 396 (IQR 310-442) days, 12 patients underwent repeat procedures, with conduction recovery in 4 of 12 and 5 of 10 previously blocked roof lines and MI lines, respectively. No complications occurred. Conclusion: Anatomical linear ablation using contiguous and optimized RF lesions results in a high rate of first-pass block at the roof but not at the MI. Due to its complex 3D architecture, the MI frequently requires additional endo- and epicardial RF lesions to be blocked.

Multicentre evaluation of non-invasive biatrial mapping for persistent atrial fibrillation ablation: the AFACART study.

AIMS: Non-invasive electrocardiogram (ECG) mapping allows the activation of the entire atrial epicardium to be recorded simultaneously, potentially identifying mechanisms critical for atrial fibrillation (AF) persistence. We sought to evaluate the utility of ECG mapping as a practical tool prior to ablation of persistent AF (PsAF) in centres with no practical experience of the system. METHODS AND RESULTS: A total of 118 patients with continuous AF duration <1 year were prospectively studied at 8 European centres. Patients were on a median of 1 antiarrhythmic drug (AAD) that had failed to restore sinus rhythm. Electrocardiogram mapping (ECVUE™, CardioInsight, USA) was performed prior to ablation to map AF drivers (local re-entrant circuits or focal breakthroughs). Ablation targeted drivers depicted by the system, followed by pulmonary vein (PV) isolation, and finally left atrial linear ablation if AF persisted. The primary endpoint was AF termination. Totally, 4.9 ± 1.0 driver sites were mapped per patient with a cumulative mapping time of 16 ± 2 s. Of these, 53% of drivers were located in the left atrium, 27% in the right atrium, and 20% in the anterior interatrial groove. Driver-only ablation resulted in AF termination in 75 of the 118 patients (64%) with a mean radiofrequency (RF) duration of 46 ± 28 min. Acute termination rates were not significantly different amongst all 8 centres (P = 0.672). Ten additional patients terminated with PV isolation and lines resulting in a total AF termination rate of 72%. Total RF duration was 75 ± 27 min. At 1-year follow-up, 78% of the patients were off AADs and 77% of the patients were free from AF recurrence. Of the patients with no AF recurrence, 49% experienced at least one episode of atrial tachycardia (AT) which required either continued AAD therapy, cardioversion, or repeat ablation. CONCLUSION: Non-invasive mapping identifies biatrial drivers that are critical in PsAF. This is validated by successful AF termination in the majority of patients treated in centres with no experience of the system. Ablation targeting these drivers results in favourable AF-free survival at 1 year, albeit with a significant rate of AT recurrence requiring further management.

Automated verification of pulmonary vein isolation in radiofrequency- and cryoballoon-guided ablation.

BACKGROUND: Verification of pulmonary vein isolation (PVI) can be challenging due to the coexistence of pulmonary vein potentials and far-field potentials. This study aimed to prospectively validate a novel algorithm for automated verification of PVI in radiofrequency (RF)-guided and cryoballoon (CB)-guided ablation strategies. METHODS: A data set of 620 (RF: 516 EGMs and CB: 104 EGMs) bipolar electrograms (EGM), recorded by circular mapping catheter placed at the left atrium-pulmonary vein (PV) junction, were prospectively analyzed by a two-step algorithm. The algorithm differentiates isolated from nonisolated EGMs based on typology and specific parameters of the bipolar EGMs. EGMs were recorded at baseline and after proven isolation in RF- and CB-guided procedures. Additionally, in the RF group, EGMs during encircling of the PVs were analyzed. RESULTS: In the RF and CB group, the algorithm correctly identifies EGMs as isolated or nonisolated with respectively 93% and 96% sensitivity and 86% and 90% specificity. In the RF subgroups of (1) baseline and proven isolated EGMs, (2) EGMs during encircling, and (3) EGMs in redo procedures sensitivity was 96%, 88%, and 100%, respectively, with specificity of 81%, 91%, and 100%. Fourteen out of 14 (100%) reconnected PVs were correctly identified as containing PVPs. Eleven out of 12 (92%) failed freeze attempts were correctly identified as being nonisolated. CONCLUSION: We validated a two-step algorithm for automated PVI verification, applicable both for RF- and CB-guided PVI. The algorithm automatically differentiates isolated from nonisolated PVs with high accuracy and without the need for pacing maneuvers.

Summary of 2016 ESC guidelines on heart failure, atrial fibrillation, dyslipidaemia and cardiovascular prevention.

During the ESC congress in September 2016 in Rome, the new ESC guidelines were presented and are now available on the ESC website ( http://www.escardio.org/guidelines ). The new guidelines cover management recommendations on following cardiovascular items: Heart failure, atrial fibrillation, dyslipidemia and cardiovascular prevention. The present document gives a summary of these guidelines and highlights the most important recommendations and changes in the management of these diseases. It will help to increase awareness about the new guidelines and may stimulate to consult the full document for specific items. Ultimately, the authors hope that this document will enhance implementation of new ESC guidelines in daily clinical practice.

A population screening programme for atrial fibrillation: a report from the Belgian Heart Rhythm Week screening programme.

AIMS: Despite the increased prevalence of atrial fibrillation (AF), data for the implementation of nationwide screening programmes are limited. The aim of this national screening study was to increase nationwide awareness about AF and stroke risk, to determine the prevalence of AF in Belgian general population using an ECG handheld machine and its feasibility to identify new AF cases. METHODS AND RESULTS: We analysed data obtained from 5 years of the 'Belgian Heart Rhythm Week' screening programme. All subjects were screened using a one-lead ECG handheld machine. Among 65 747 subjects screened, AF was recorded in 911, with an overall prevalence of 1.4% [95% confidence interval (CI) 1.2-1.6%]. High thrombo-embolic risk, as assessed by CHA2DS2-VASc score ≥2, was recorded in 69% of AF subjects. In subjects with high thrombo-embolic risk, only 5.4% were treated with oral anticoagulant (OAC) and 5.8% were treated with OAC and antiplatelet drugs. Among recorded AF cases, the use of the ECG handheld machine allowed identification of 603 new AF patients (1.1%, 95% CI 0.9-1.3%). Factors associated with incident AF were chronic heart failure (P < 0.001), age (P < 0.001), diabetes mellitus (P < 0.001), previous stroke (P < 0.001), vascular disease (P < 0.001), and male sex (P < 0.001). CONCLUSION: In this Belgian national screening programme, prevalence of AF was 1.4%. The use of an ECG handheld machine is feasible to identify a significant number of new AF cases, most with a high thrombo-embolic risk. Given the low OAC use recorded, greater efforts in AF detection and treatment are urgently needed to reduce the burden of stroke associated with this common arrhythmia.

Variability in interpretation of the electrocardiogram in young athletes: an unrecognized obstacle for electrocardiogram-based screening protocols.

AIMS: To assess in young athletes (i) the variability in the percentage of abnormal electrocardiograms (ECGs) using different criteria and (ii) the variability in ECG interpretation among cardiologists and sport physicians. METHODS AND RESULTS: Electrocardiograms of 138 athletes were categorized by seven cardiologists according to the original European Society of Cardiology (ESC) criteria by Corrado (C), subsequently modified by Uberoi (U), Marek (M), and the Seattle criteria (S); seven sports physicians only used S criteria. The percentage of abnormal ECGs for each physician was calculated and the percentage of complete agreement was assessed. For cardiologists, the median percentage of abnormal ECGs was 14% [interquartile range (IQR) 12.5-20%] for C, 11% (IQR 9.5-12.5%) for U [not significant (NS) compared with C], 11% (IQR 10-13%) for M (NS compared with C), and 7% (IQR 5-8%) for S (P < 0.005 compared with C); complete agreement in interpretation was 64.5% for C, 76% for U (P < 0.05 compared with C), 74% for M (NS compared with C), and 84% for S (P < 0.0005 compared with C). Sport physicians classified a median of 7% (IQR 7-11%) of ECGs as abnormal by S (P = NS compared with cardiologists using S); complete agreement was 72% (P < 0.05 compared with cardiologists using S). CONCLUSION: Seattle criteria reduced the number of abnormal ECGs in athletes and increased agreement in classification. However, variability in ECG interpretation by cardiologists and sport physicians remains high and is a limitation for ECG-based screening programs.

Catheter ablation of atrial fibrillation in patients at low thrombo-embolic risk: efficacy and safety of a simplified periprocedural anticoagulation strategy.

BACKGROUND: To prevent thrombo-embolic (TE) events during ablation of atrial fibrillation (AF), warfarin is recommended in all patients irrespective of baseline TE risk. We evaluated the efficacy and safety of a simplified periprocedural anticoagulation strategy of aspirin (ASA) and low molecular weight heparin (LMWH) in patients at low TE risk. METHODS: We collected data from 214 low TE risk patients (CHADS2 score ≤1 and no warfarin at baseline) undergoing pulmonary vein isolation. After discontinuation of ASA, periprocedural antithrombotic therapy consisted of therapeutic subcutaneous LMWH injections (nadroparin 1 mL/kg once daily) from 10 days before until 10 days after the procedure, followed by ASA in all patients. At the time of procedure, transesophageal echocardiography (TEE) was not performed on a routine basis. During the procedure, unfractionated heparin was administered to achieve an ACT between 350 and 400 seconds. Data on TE events (stroke or transient ischemic attack), cardiac tamponade/perforation, and major vascular access complications within 3 months after the procedure were collected. RESULTS: Mean CHADS2 was 0.3 ± 0.5. TEE was performed in 3% of patients. No periprocedural TE events occurred. No cardiac tamponade/perforation was observed. Major vascular access complications occurred in 3 patients (1.4%). No permanent injury was observed (0%). CONCLUSION: In selected low TE risk patients undergoing ablation for AF, a short period of periprocedural therapeutic anticoagulation with LMWH together with aspirin is an effective and safe strategy to prevent TE events. If confirmed in a randomized trial, this approach might simplify periprocedural antithrombotic management in ablation of selected AF patients.

Lessons from dissociated pulmonary vein potentials: entry block implies exit block.

AIMS: Prior reports using pacing manoeuvres, demonstrated an up to 42% prevalence of residual pulmonary vein to left atrium (PV-LA) exit conduction after apparent LA-PV entry block. We aimed to determine in a two-centre study the prevalence of residual PV-LA exit conduction in the presence of unambiguously proven entry block and without pacing manoeuvres. METHODS AND RESULTS: Of 378 patients, 132 (35%) exhibited spontaneous pulmonary vein (PV) potentials following circumferential PV isolation guided by three-dimensional mapping and a circular mapping catheter. Pulmonary vein automaticity was regarded as unambiguous proof of LA-PV entry block. We determined the prevalence of spontaneous exit conduction of the spontaneous PV potentials toward the LA. Pulmonary vein automaticity was observed in 171 PVs: 61 right superior PV, 33 right inferior PV, 47 left superior PV, and 30 left inferior PV. Cycle length of the PV automaticity was >1000 ms in all cases. Spontaneous PV-LA exit conduction was observed in one of 171 PVs (0.6%). In a subset of 69 PVs, pacing from within the PV invariably confirmed PVLA exit block. CONCLUSION: Unidirectional block at the LA-PV junction is unusual (0.6%). This observation is supportive of LA-PV entry block as a sufficient electrophysiological endpoint for PV isolation.

Implantable cardiac defibrillators in octogenarians.

OBJECTIVE: Implantable cardiac defibrillators (ICD) implantation in the very elderly remains controversial. We aimed to describe the experience and outcome of patients over 80 years old implanted with an ICD in Belgium. METHODS: Data were extracted from the national QERMID-ICD registry. All implantations performed in octogenarians between February 2010 and March 2019 were analysed. Data on baseline patient characteristics, type of prevention, device configuration and all-cause mortality were available. To determine predictors of mortality, multivariable Cox proportional hazard regression modelling was performed. RESULTS: Nationwide, 704 primo ICD implantations were performed in octogenarians (median age 82, IQR 81-83 years; 83% male and 45% secondary prevention). During a mean follow-up of 3.1 ± 2.3 years, 249 (35%) patients died, of which 76 (11%) within the first year after implantation. In multivariable Cox regression analysis age (HR = 1.15, P = 0.004), oncological history (HR = 2.43, P = 0.027) and secondary prevention (HR = 2.23, P = 0.001) were independently associated with 1-year mortality. A better preserved left ventricular ejection fraction (LVEF) was associated with a better outcome (HR = 0.97, P = 0.002). Regarding overall mortality multivariable analysis withheld age, history of atrial fibrillation, centre volume and oncological history as significant predictors. Higher LVEF was again protective (HR = 0.99, P = 0.008). CONCLUSIONS: Primary ICD implantation in octogenarians is not often performed in Belgium. Among this population, 11% died within the first year after ICD implantation. Advanced age, oncological history, secondary prevention and a lower LVEF were associated with an increased one-year mortality. Age, low LVEF, atrial fibrillation, centre volume and oncological history were indicative of higher overall mortality.

Inequality between women and men in ICD implantation.

Background: The impact of sex on ICD implantation practice and survival remain a topic of controversy. To assess sex-specific differences in ICD implantation practice we compared clinical characteristics and survival in women and men. Methods: From a nationwide registry, all new ICD implantations performed between 01/02/2010 and 31/01/2019 in Belgian patients were analyzed retrospectively. Baseline characteristics and survival rates were compared between sexes. To identify predictors of mortality, multivariable Cox regression was performed. Results: Only 3096 (20.9%) of 14,787 ICD implantations were performed in women. Within each type of underlying cardiomyopathy, the proportion women were lower than men. The main indication in men was ischemic vs dilated cardiomyopathy in women. Women were overall younger (59.1 ± 15.1 vs 62.6 ± 13.1 years; p < 0.001) and had less comorbidities except for oncological disease. More women functioned in NYHA-class III (33.6% vs 27.9%; p < 0.001) and had a QRS > 150 ms (29.4% vs 24.3%; p < 0.001), consistent with a higher use of CRT-D devices (31.7% vs 25.1%; p < 0.001). Women had more complications, reflected by the need to more re-interventions within 1 year (4.3% vs 2.7%, p < 0.001). After correction for covariates, sex-category was not a significant predictor of mortality (p = 0.055). Conclusion: There is a significant sex-disparity in ICD implantation rates, not fully explained by epidemiological differences in the prevalence of cardiomyopathies, which could imply an undertreatment of women. Women differ from men in baseline characteristics at implantation suggesting a selection bias. Further research is necessary to evaluate if women receive equal sudden cardiac death prevention.