Flecainide to prevent atrial arrhythmia after patent foramen ovale closure Rationale and design of the randomized AFLOAT study

INTRODUCTION

Atrial arrhythmia is the most common complication of patent foramen ovale (PFO) closure. The real incidence of post-PFO closure atrial arrhytmia and whether this complication can be prevented is unknown.

METHODS/DESIGN

The Assessment of Flecainide to Lower the patent foramen Ovale closure risk of Atrial fibrillation or Tachycardia (AFLOAT) trial is a prospective, national, multicentre, randomized, open-label, superiority trial with a blind evaluation of all the endpoints (PROBE design). A total of 186 patients are randomized in a 1:1:1 ratio immediately after PFO closure to receive Flecainide (150 mg per day in a single sustained-release dose) for 6 months (Group 1), Flecainide (150 mg per day in a single sustained-release dose) for 3 months (Group 2), or no additional treatment (standard of care) for 6 months (Group 3). The primary endpoint is the percentage of patients with at least one episode of symptomatic or asymptomatic atrial arrhythmia episode (≥30s) recorded within 3 months after PFO closure on long-term monitoring with an insertable cardiac monitor. Whether 3 months of treatment is sufficient compared to 6 months will be analyzed as a secondary objective of the study.

CONCLUSION

AFLOAT is the first trial to test the hypothesis that a short treatment with oral Flecainide can prevent the new-onset of atrial arrhythmia after PFO closure. Clinical trial registration: NCT05213104 (clinicaltrials.gov).

One-year mortality and causes of death after stereotactic radiation therapy for refractory ventricular arrhythmias: A systematic review and pooled analysis

Patients treated with cardiac stereotactic body radiation therapy (radioablation) for refractory ventricular arrhythmias are patients with advanced structural heart disease and significant comorbidities. However, data regarding 1-year mortality after the procedure are scarce. This systematic review and pooled analysis aimed at determining 1-year mortality after cardiac radioablation for refractory ventricular arrhythmias and investigating leading causes of death in this population. MEDLINE/EMBASE databases were searched up to January 2023 for studies including patients undergoing cardiac radioablation for the treatment of refractory ventricular arrhythmias. Quality of included trials was assessed using the NIH Tool for Case Series Studies (PROSPERO CRD42022379713). A total of 1,151 references were retrieved and evaluated for relevance. Data were extracted from 16 studies, with a total of 157 patients undergoing cardiac radioablation for refractory ventricular arrhythmias. Pooled 1-year mortality was 32 % (95 %CI: 23-41), with almost half of the deaths occurring within three months after treatment. Among the 157 patients, 46 died within the year following cardiac radioablation. Worsening heart failure appeared to be the leading cause of death (52 %), although non-cardiac mortality remained substantial (41 %) in this population. Age≥70yo was associated with a significantly higher 12-month all-cause mortality (p<0.022). Neither target volume size nor radiotherapy device appeared to be associated with 1-year mortality (p = 0.465 and p = 0.199, respectively). About one-third of patients undergoing cardiac stereotactic body radiation therapy for refractory ventricular arrhythmias die within the first year after the procedure. Worsening heart failure appears to be the leading cause of death in this population.

Cardiac stereotactic radiation therapy for refractory ventricular arrhythmias in patients with left ventricular assist devices

Left ventricular assist device (LVAD) implantation is an established treatment for patients with advanced heart failure refractory to medical therapy. However, the incidence of ventricular arrhythmias (VAs) is high in this population, both in the acute and delayed phases after implantation. About one-third of patients implanted with an LVAD will experience sustained VAs, predisposing these patients to worse outcomes and complicating patient management. The combination of pre-existing myocardial substrate and complex electrical remodeling after LVAD implantation account for the high incidence of VAs observed in this population. LVAD patients presenting VAs refractory to antiarrhythmic therapy and catheter ablation procedures are not rare. In such patients, treatment options are extremely limited. Stereotactic body radiation therapy (SBRT) is a technique that delivers precise and high doses of radiation to highly defined targets, reducing exposure to adjacent normal tissue. Cardiac SBRT has recently emerged as a promising alternative with a growing number of case series reporting the effectiveness of the technique in reducing the VA burden in patients with arrhythmias refractory to conventional therapies. The safety profile of cardiac SBRT also appears favorable, even though the current clinical experience remains limited. The use of cardiac SBRT for the treatment of refractory VAs in patients implanted with an LVAD are even more scarce. This review summarizes the clinical experience of cardiac SBRT in LVAD patients and describes technical considerations related to the implementation of the SBRT procedure in the presence of an LVAD.

ATE Score Diagnostic Accuracy for Predicting the Absence of Intra-Atrial Thrombi Before AF Ablation

BACKGROUND

In a preliminary study in patients hospitalized for catheter ablation of atrial fibrillation (AF), the atrial thrombus exclusion (ATE) score (stroke, hypertension, heart failure, and D-dimers >270 ng/mL) was developed to rule out the diagnosis of intra-atrial thrombus, with a negative predictive value (NPV) of 100%, and to avoid performing transesophageal echocardiography (TEE).

OBJECTIVES

The present study was designed to prospectively confirm the NPV of the ATE score in an independent population.

METHODS

Consecutive patients hospitalized for catheter ablation of AF or left atrial tachycardia (LAT) were prospectively enrolled in a multicenter study. D-dimer levels were measured within 48 hours before ablation. An ATE score of 0 was considered predictive of no thrombus. TEE was routinely performed at the beginning or just before the ablation procedure. The primary endpoint was the presence of atrial thrombus diagnosed by TEE.

RESULTS

The analysis included 3,072 patients (53.3% paroxysmal AF, 36.7% persistent AF, and 10% LAT). A thrombus was detected in 29 patients (0.94%; 95% CI: 0.63%-1.35%), all on appropriate anticoagulant therapy. An ATE score of 0 was observed in 818 patients (26.6%), and the sensitivity, specificity, positive predictive value, and NPV were 93.1%, 26.8%, 1.2%, and 99.8%, respectively. Follow-up of the 2 false negative patients revealed the persistence of chronic organized thrombi.

CONCLUSIONS

In patients hospitalized for catheter ablation of AF or LAT, the ATE score identifies a population at very low risk for atrial thrombus. In consultation with the patient, the cardiologist may consider not performing a preoperative TEE in case of an ATE score of 0.

Procedure-Related Complications of Catheter Ablation for Atrial Fibrillation

BACKGROUND

Catheter ablation of atrial fibrillation (AF) is a commonly performed procedure. However, it is associated with potentially significant complications. Reported procedure-related complication rates are highly variable, depending in part on study design.

OBJECTIVES

The purpose of this systematic review and pooled analysis was to determine the rate of procedure-related complications associated with catheter ablation of AF using data from randomized control trials and to assess temporal trends.

METHODS

MEDLINE and EMBASE databases were searched from January 2013 to September 2022 for randomized control trials that included patients undergoing a first ablation procedure of AF using either radiofrequency or cryoballoon (PROSPERO, CRD42022370273).

RESULTS

A total of 1,468 references were retrieved, of which 89 studies met inclusion criteria. A total of 15,701 patients were included in the current analysis. Overall and severe procedure-related complication rates were 4.51% (95% CI: 3.76%-5.32%) and 2.44% (95% CI: 1.98%-2.93%), respectively. Vascular complications were the most frequent type of complication (1.31%). The next most common complications were pericardial effusion/tamponade (0.78%) and stroke/transient ischemic attack (0.17%). The procedure-related complication rate during the most recent 5-year period of publication was significantly lower than during the earlier 5-year period (3.77% vs 5.31%; P = 0.043). The pooled mortality rate was stable over the 2 time periods (0.06% vs 0.05%; P = 0.892). There was no significant difference in complication rate according to pattern of AF, ablation modality, or ablation strategies beyond pulmonary vein isolation.

CONCLUSIONS

Procedure-related complications and mortality rates associated with catheter ablation of AF are low and have declined in the past decade.

A worldwide survey on incidence, management and prognosis of oesophageal fistula formation following atrial fibrillation catheter ablation: The POTTER-AF study

AIMS

Oesophageal fistula represents a rare but dreadful complication of atrial fibrillation catheter ablation. Data on its incidence, management and outcome are sparse.

METHODS AND RESULTS

This international multicenter registry investigates the characteristics of oesophageal fistulae after treatment of atrial fibrillation by catheter ablation. A total of 553,729 catheter ablation procedures (radiofrequency: 62.9%, cryoballoon: 36.2%, other modalities: 0.9%) were performed at 214 centers in 35 countries. In 78 centers 138 patients (0.025%, radiofrequency: 0.038%, cryoballoon: 0.0015% (p<0.0001)) were diagnosed with an oesophageal fistula. Periprocedural data were available for 118 patients (85.5%). Following catheter ablation, the median time to symptoms and the median time to diagnosis were 18 (7.75, 25; range: 0-60) days and 21 (15, 29.5; range: 2-63) days, respectively. The median time from symptom onset to oesophageal fistula diagnosis was 3 (1, 9; range: 0-42) days. The most common initial symptom was fever (59.3%). The diagnosis was established by chest computed tomography in 80.2% of patients. Oesophageal surgery was performed in 47.4% and direct endoscopic treatment in 19.8%, and conservative treatment in 32.8% of patients. The overall mortality was 65.8%. Mortality following surgical (51.9%) or endoscopic treatment (56.5%) was significantly lower as compared to conservative management (89.5%) (odds ratio 7.463 (2.414, 23.072) p<0.001).

CONCLUSIONS

Oesophageal fistula after catheter ablation of atrial fibrillation is rare and occurs mostly with the use of radiofrequency energy rather than cryoenergy. Mortality without surgical or endoscopic intervention is exceedingly high.

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.

Incidence and management of atrioventricular conduction disorders in new-onset left bundle branch block after TAVI: A prospective multicenter study

BACKGROUND

New-onset left bundle branch block (LBBB) is one of the most frequent complications after transcatheter aortic valve implantation (TAVI) and is associated with delayed high degree atrioventricular (AV) block.

OBJECTIVES

The objectives of this study were to determine the incidence of AV block in such a population and to assess the performance and safety of a risk stratification algorithm on the basis of electrophysiology study (EPS) followed by implantation of a pacemaker or implantable loop recorder (ILR).

METHODS

This was a prospective open-label study with 12-month follow-up. From June 8, 2015, to November 8, 2018, 183 TAVI recipients (mean age 82.3 ± 5.9 years) were included at 10 centers. New-onset LBBB after TAVI persisting for >24 hours was assessed by electrophysiology study during initial hospitalization. High-risk patients (His-ventricle interval ≥70 ms) were implanted with a dual-chamber pacemaker recording AV conduction disturbance episodes. Patients at lower risk were implanted with an ILR with automatic remote monitoring.

RESULTS

A high-grade AV conduction disorder was identified in 56 patients (30.6%) at 12 months. Four subjects were symptomatic, all in the ILR group. No complications were associated with the stratification procedure. Patients with His-ventricle interval ≥70 ms displayed more high-grade AV conduction disorders (53.2% [25 of 47] vs 22.8% [31 of 136]; P < .001). In a multivariate analysis, His-ventricle interval ≥70 ms was independently associated with the occurrence of a high-grade conduction disorder (subdistribution hazard ratio 2.4; 95% confidence interval 1.2-4.8; P = .010).

CONCLUSION

New-onset LBBB after TAVI was associated with high rates of high-grade AV conduction disturbances. The stratification algorithm provided safe and valuable aid to management decisions and reliable guidance on pacemaker implantation.

Premature atrial contractions: A predictor of atrial fibrillation and a relevant marker of atrial cardiomyopathy

An increased burden of premature atrial contractions (PACs) has long been considered a benign phenomenon. However, strong evidence of their involvement in the occurrence of atrial fibrillation (AF), ischemic stroke, and excess mortality suggests the need for management. The central question to be resolved is whether increased ectopic atrial rhythm is only a predictor of AF or whether it is a marker of atrial cardiomyopathy and therefore of ischemic stroke. After reviewing the pathophysiology of PACs and its impact on patient prognosis, this mini-review proposes to 1) detail the physiological and clinical elements linking PACs and AF, 2) present the evidence in favor of supraventricular ectopic activity as a marker of cardiomyopathy, and 3) outline the current limitations of this concept and the potential future clinical implications.

Incidence, Characteristics, and Outcomes of Ventricular Fibrillation Complicating Acute Myocardial Infarction in Women Admitted Alive in the Hospital

Background

Little data are available in women presenting with ventricular fibrillation (VF) in the setting of acute myocardial infarction (AMI). We assessed frequency, predictors of VF, and outcomes, with a special focus on women compared with men.

Methods and Results

Data were analyzed from the FAST‐MI (French Registry of Acute ST‐Elevation or Non‐ST‐Elevation Myocardial Infarction) program, which prospectively included 14 406 patients admitted to French cardiac intensive care units ≤48 hours from AMI onset between 1995 and 2015 (mean age, 66±14 years; 72% men; mean left ventricular ejection fraction, 52±12%; 59% with ST‐segment–elevation myocardial infarction). A total of 359 patients developed VF during AMI, including 81 women (2.0% of 4091 women) and 278 men (2.7% of 10 315 men, P=0.02). ST‐segment–elevation myocardial infarction (odds ratio [OR], 2.29 [95% CI, 1.75–2.99]; P<0.001) was independently associated with the onset of VF during AMI. In contrast, female sex (OR, 0.73 [95% CI, 0.56–0.95]; P=0.02), hypertension (OR, 0.75 [95% CI, 0.60–0.94]; P=0.01), and prior myocardial infarction (OR, 0.69 [95% CI, 0.50–0.96]; P=0.03) were protective factors. Women were less likely to have cardiac intervention than men (percutaneous coronary intervention during hospitalization 48.1% versus 66.9%, respectively; P=0.04) with a higher 1‐year mortality in women compared with men (50.6% versus 37.4%, respectively; P=0.03), including increased in‐hospital mortality (42.0% versus 32.7%, respectively; P=0.12). After adjustment, female sex was no longer associated with a worse 1‐year mortality (adjusted hazard ratio, 1.10 [95% CI, 0.75–1.61]; P=0.63).

Conclusions

Women have lower risk of developing VF during AMI compared with men. However, they are less likely to receive cardiac interventions than men, possibly contributing to missed opportunities of improved outcomes.

Outcome of Patients with Early Repolarization Pattern and Syncope

BACKGROUND

Syncope in patients with an early repolarization (ER) pattern presents a challenge for clinicians as it has been identified as an indicator of a higher risk of life-threatening ventricular arrhythmias (VAs).

OBJECTIVE

This study aimed to analyze the outcome of patients with an ER pattern and syncope, and to evaluate the factors predictive of VAs.

METHODS

Over a period of 5 years, we enrolled 143 patients with an ER pattern and syncope in a multicenter prospective registry.

RESULTS

Following the initial examinations, 97 patients (67.8%) were implanted with a device allowing electrocardiogram monitoring, including 84 with an implantable loop recorder. During a mean follow-up of 68 ± 34 months, we documented 16 arrhythmias presumably responsible for syncope (5 VAs, 10 bradycardias, and 1 supraventricular tachycardia). Additionally, recurrent syncope not associated with electrocardiogram documentation occurred in 16 patients (11.2%). The cause of syncope was identified in 23 of 97 (23.8%) patients with a monitoring device. The 5-year incidence of VAs and arrhythmic events presumably responsible for syncope was 4.9% and 11.0%, respectively. Patients who developed VAs showed no prodromes or specific triggers at the time of syncope. Neither the presence of a family history of sudden cardiac death nor the previously reported high-risk electrocardiographic parameters differed between patients with and without VAs.

CONCLUSIONS

VAs occurred in 4.9% of patients with an ER pattern and syncope. Device implantation based on detailed history taking seems to be a reasonable strategy. Previously reported high-risk electrocardiographic patterns did not identify patients with VAs.

Prevention of Atrial Fibrillation After Atrial Flutter Ablation With Ramipril (from the PREFACE Study)

The clinical efficacy of the inhibitors of the renin-angiotensin-aldosterone system (RAAS) as an upstream therapy for atrial fibrillation (AF) prevention is controversial. No study has itemized so far the role of RAAS inhibitors in AF prevention after atrial flutter (AFL) ablation. This trial aims to investigate the effect of ramipril compared with placebo on AF occurrence in patients hospitalized for AFL ablation without structural heart disease. The Prevention of Atrial Fibrillation by Inhibition Conversion Enzyme (ICE) After Radiofrequency Ablation of Atrial Flutter (PREFACE) trial was a prospective, multicenter, randomized, double-blind, double-dummy trial depicting the AF occurrence during a 12-month follow-up as the primary end point. A total of 198 patients hospitalized for AFL ablation were enrolled in the trial and randomized to placebo or ramipril 5 mg/day. Patients were followed up during 1 year after AFL ablation using 1-week Holter electrocardiogram at 3, 6, 9, and 12 months. The intention-to-treat population encompassed 97 patients in the ramipril group and 101 patients in the placebo group. The primary end point, such as AF occurrence during the 1-year follow-up, was not different between the 2 groups (p = 0.96). Secondary end points, including the occurrence of supraventricular arrhythmia (p = 0.50), heart failure, stroke, and death, were not different between the 2 groups. Safety outcome parameters, including serious adverse events leading to treatment disruption (p = 0.10), hypotension, impairment of renal function, and elevated serum potassium level, also were not different between the 2 groups. In conclusion, RAAS inhibition using ramipril does not reduce AF occurrence in patients facing AFL ablation during the 1-year follow-up.

Distance between the descending aorta and the left inferior pulmonary vein as a determinant of biophysical parameters during paroxysmal atrial fibrillation cryoablation

INTRODUCTION

The distance from the descending aorta (DA) to the posterior wall of the left atrium (LA) is variable. We aimed to determine whether the proximity between the DA and the left inferior pulmonary vein (LIPV) ostium has an impact on biophysical parameters and cryoballoon (CB) ablation efficacy during LIPV freezing.

METHODS

Patients referred for CB-ablation of atrial fibrillation (AF) in two high-volume centers were included. Cryoablation data were collected prospectively for each patient. The anatomical relationships between the LIPV and the DA (distance LIPV ostium-DA, presence of an aortic imprint on the posterior aspect of the LIPV) were then retrospectively analysed on the LA computed tomography scans realized before AF ablation.

RESULTS

A total of 350 patients were included (70% men, 59.7 ± 11.5 years). The decrease in the Ostium-DA distance was significantly correlated to the increase in the time-to-isolation (TTI) (r = -.31; p = .036), with less negative temperature (r = -.11; p = .045). Similarly, the presence of an aortic imprint on the LIPV was associated with a longer TTI (p < .001). The analysis of redo procedures data shows a trend toward the presence of shorter ostium-DA distances (15.3 ± 3.29 vs. 18.1 ± 4.99, p = .15) and more frequent aortic imprints (63.6% vs. 47.5%, p = .34) in patients with LIPV reconnection as opposed to patients without reconnection in the LIPV.

CONCLUSION

Our findings indicated that the DA seems to have a "radiator" effect influencing LIPV cryoablation parameters during CB-ablation. Additional studies will be needed to elucidate whether this biophysical influence has a clinical impact in LIPVs reconnections.

FRAGILE: FRench Attitude reGistry in case of ICD LEad replacement

AIMS

FRench Attitude reGistry in case of ICD LEad replacement (FRAGILE) registry was set-up to describe the attitude in different French institutions in case of implantable cardioverter-defibrillator (ICD) lead replacement, extraction, or abandonment and to compare outcomes in both groups.

METHODS AND RESULTS

Prospective observational study comparing two attitudes in case of ICD lead replacement, extraction, or abandonment. Primary endpoint describes the attitude in different French centres, collect parameters that may influence the decision. Secondary endpoint compares early and mid-term (2 years) complications in both groups.Between April 2013 and April 2017, 552 patients were included in 32 centres. 434 (78.6%) were male, mean patient's age was 60.3 ± 14.4 years. In 56.9% of the cases, the decision was to explant the lead. Patients in the extraction group were younger than in the abandonment group (56.7 ± 14.5 vs. 65 ± 12.7 P < 0.0001) and less likely to have comorbidities (46.5% vs. 58.3% of the patients P = 0.022). The mean lead dwelling time was significantly longer in the abandonment group as compared with the extraction group (7.6 ± 3.9 vs. 5.2 ± 3.1 years, P < 0.0001). There was no statistical difference between both groups concerning early and 2 years complications.

CONCLUSION

In this registry, the strategy in case of non-infected ICD lead replacement was mainly influenced by patient's age and comorbidities and lead dwelling time. No difference was observed in outcomes in both strategies.

Wearable cardioverter-defibrillator in patients with a transient risk of sudden cardiac death: the WEARIT-France cohort study

Aims 

We aimed to provide contemporary real-world data on wearable cardioverter-defibrillator (WCD) use, not only in terms of effectiveness and safety but also compliance and acceptability.

Methods and results 

Across 88 French centres, the WEARIT-France study enrolled retrospectively patients who used the WCD between May 2014 and December 2016, and prospectively all patients equipped for WCD therapy between January 2017 and March 2018. All patients received systematic education session through a standardized programme across France at the time of initiation of WCD therapy and were systematically enrolled in the LifeVest Network remote services. Overall, 1157 patients were included (mean age 60 ± 12 years, 16% women; 46% prospectively): 82.1% with ischaemic cardiomyopathy, 10.3% after implantable cardioverter-defibrillator explant, and 7.6% before heart transplantation. Median WCD usage period was 62 (37–97) days. Median daily wear time of WCD was 23.4 (22.2–23.8) h. In multivariate analysis, younger age was associated with lower compliance [adjusted odds ratio (OR) 0.97, 95% confidence interval (CI) 0.95–0.99, P < 0.01]. A total of 18 participants (1.6%) received at least one appropriate shock, giving an incidence of appropriate therapy of 7.2 per 100 patient-years. Patient-response button allowed the shock to be aborted in 35.7% of well-tolerated sustained ventricular arrhythmias and in 95.4% of inappropriate ventricular arrhythmia detection, finally resulting in an inappropriate therapy in eight patients (0.7%).

Conclusion

Our real-life findings reinforce previous studies on the efficacy and safety of the WCD in the setting of transient high-risk group in selected patients. Moreover, they emphasize the fact that when prescribed appropriately, in concert with adequate patient education and dedicated follow-up using specific remote monitoring system, compliance with WCD is high and the device well-tolerated by the patient.

Comparison of clockwise and counterclockwise right atrial flutter using high-resolution mapping and automated velocity measurements

BACKGROUND

Only few studies have been performed that explore the electrophysiological differences between clockwise (CW) and counterclockwise (CCW) right atrial (RA) cavotricuspid isthmus (CTI)-dependent atrial flutter (AFL) using the high-resolution Rhythmia mapping system.

OBJECTIVES

We sought to compare CW and CCW CTI-dependent AFL in pure right AFL patients (pts) using the ultra-high-definition (ultra-HD) Rhythmia mapping system and we mathematically developed a cartography model based on automatic velocity RA measurements to identify electrophysiological AFL specificities.

METHODS AND RESULTS

Thirty-three pts were recruited. The mean age was 71 ± 13 years old. The sinus venosus (SV) block line was present in 32/33 of cases (97%) and no significant difference was found between CCW and CW CTI AFL (100% vs. 91%; p = .7). No line was localized in the region of the crista terminalis (CT). A superior gap was present in the posterior line in 14/31 (45.2%) but this was similarly present in CCW AFL, when compared to CW AFL (10/22 [45.5%] vs. 4/10 [40%]; p = .9). When present, the extension of the posterior line of block was observed in 18/31 pts (58%) without significant differences between CCW and CW CI AFL (12/22 [54.5%] vs. 6/10 [60%]; p = .9) The Eustachian ridge line of block was similarly present in both groups (82% [18/22] vs. 45.5% [5/11]; p = .2). The absence of the Eustachian ridge line of block led to significantly slowed velocity in this area (28 ± 10 cm/s; n = 8), and the velocities were similarly altered between both groups (26 ± 10 [4/22] vs. 29.8 ± 11 cm/s [4/11]; p = .6). We created mathematical, three-dimensional RA reconstruction-velocity model measurements. In each block localization, when the block line was absent, velocity was significantly slowed (≤20 cm/s). A systematic slowdown in conduction velocity was observed at the entrance and exit of the CTI in 100% of cases. This alteration to the conduction entrance was localized at the lateral side of the CTI for the CCW AFL and at the septal side of the CTI for CW AFL. The exit-conduction alteration was localized at the CTI septal side for the CCW AFL and at the CTI lateral side for the CW AFL.

CONCLUSION

The ultra-HD Rhythmia mapping system confirmed the absence of significant electrophysiological differences between CCW and CW AFL. The mechanistic posterior SV and Eustachian ridge block lines were confirmed in each arrhythmia. A systematic slowing down at the entrance and exit of the CTI was demonstrated in both CCW and CW AFL, but in reverse positions.

Predictors of high-degree conduction disturbances and pacemaker implantation after transcatheter aortic valve replacement: Prognostic role of the electrophysiological study

BACKGROUND

Predictors of high-degree atrioventricular block (HAVB) after transcatheter aortic valve replacement (TAVR) are recognized, but the electrophysiological study's (EPS) role is still a subject to debate. The objective of our study was to determine factors associated with PPM implantation including the potential role of EPS before and/or after TAVR.

METHODS AND RESULTS

Seventy four consecutive patients (pts) were included and 21 pts (28.4%) received a PPM during the immediate postoperative follow-ups (until Day 5): HAVB in 15 pts (71.4%), prophylactic implantation due to a documented increased HV interval ≥ 95-100 ms plus LBBB in 2 pts (9.5%), a high-degree HV block evidenced at the EPS plus LBBB in 3 pts (14.3%) and one additional patient was implanted for AV-block in presence of AFib (4.8%). In the multivariate model 1 including parameters before TAVR, both prosthesis diameter and PR lengthening remained significantly associated with PPM as well RBBB. In the multivariate model 2 including parameters after TAVR, only HV remained significantly associated with the risk of PPM (OR = 1.15 (1.05-1.26), p = .004). When all the significant variables in models 1 and 2 were analyzed together in model 3, only HV after TAVR remained significantly associated with an increased risk of PPM.

CONCLUSIONS

In this prospective observational study, it was revealed that a Day 4-5 EPS is likely to more precisely stratify the risk of PPM implantation regarding its ability to discover asymptomatic severe infra-hisian conduction disturbances particularly in presence of LBBB. Multivariate analysis confirmed the prognostic value of HV alteration.

Comparison of Atrial Remodeling Caused by Sustained Atrial Flutter Versus Atrial Fibrillation

BACKGROUND

Atrial flutter (AFL) and atrial fibrillation (AF) are associated with AF-promoting atrial remodeling, but no experimental studies have addressed remodeling with sustained AFL.

OBJECTIVES

This study aimed to define the atrial remodeling caused by sustained atrial flutter (AFL) and/or atrial fibrillation (AF).

METHODS

Intercaval radiofrequency lesions created a substrate for sustained isthmus-dependent AFL, confirmed by endocavity mapping. Four groups (6 dogs per group) were followed for 3 weeks: sustained AFL; sustained AF (600 beats/min atrial tachypacing); AF superimposed on an AFL substrate (AF+AFLs); sinus rhythm (SR) with an AFL substrate (SR+AFLs; control group). All dogs had atrioventricular-node ablation and ventricular pacemakers at 80 beats/min to control ventricular rate.

RESULTS

Monitoring confirmed spontaneous AFL maintenance >99% of the time in dogs with AFL. At terminal open-chest study, left-atrial (LA) effective refractory period was reduced similarly with AFL, AF+AFLs and AF, while AF vulnerability to extrastimuli increased in parallel. Induced AF duration increased significantly in AF+AFLs and AF, but not AFL. Dogs with AF+AFLs had shorter cycle lengths and substantial irregularity versus dogs with AFL. LA volume increased in AF+AFLs and AF, but not dogs with AFL, versus SR+AFLs. Optical mapping showed significant conduction slowing in AF+AFLs and AF but not AFL, paralleling atrial fibrosis and collagen-gene upregulation. Left-ventricular function did not change in any group. Transcriptomic analysis revealed substantial dysregulation of inflammatory and extracellular matrix-signaling pathways with AF and AF+ALs but not AFL.

CONCLUSIONS

Sustained AFL causes atrial repolarization changes like those in AF but, unlike AF or AF+AFLs, does not induce structural remodeling. These results provide novel insights into AFL-induced remodeling and suggest that early intervention may be important to prevent irreversible fibrosis when AF intervenes in a patient with AFL.

Prediction of ventricular arrhythmias in patients with a spontaneous Brugada type 1 pattern: the key is in the electrocardiogram

AIMS

There is currently no reliable tool to quantify the risks of ventricular fibrillation or sudden cardiac arrest (VF/SCA) in patients with spontaneous Brugada type 1 pattern (BrT1). Previous studies showed that electrocardiographic (ECG) markers of depolarization or repolarization disorders might indicate elevated risk. We aimed to design a VF/SCA risk prediction model based on ECG analyses for adult patients with spontaneous BrT1.

METHODS AND RESULTS

This retrospective multicentre international study analysed ECG data from 115 patients (mean age 45.1 ± 12.8 years, 105 males) with spontaneous BrT1. Of these, 45 patients had experienced VF/SCA and 70 patients did not experience VF/SCA. Among 10 ECG markers, a univariate analysis showed significant associations between VF/SCA and maximum corrected Tpeak-Tend intervals ≥100 ms in precordial leads (LMaxTpec) (P < 0.001), BrT1 in a peripheral lead (pT1) (P = 0.004), early repolarization in inferolateral leads (ER) (P < 0.001), and QRS duration ≥120 ms in lead V2 (P = 0.002). The Cox multivariate analysis revealed four predictors of VF/SCA: the LMaxTpec [hazard ratio (HR) 8.3, 95% confidence interval (CI) 2.4-28.5; P < 0.001], LMaxTpec + ER (HR 14.9, 95% CI 4.2-53.1; P < 0.001), LMaxTpec + pT1 (HR 17.2, 95% CI 4.1-72; P < 0.001), and LMaxTpec + pT1 + ER (HR 23.5, 95% CI 6-93; P < 0.001). Our multidimensional penalized spline model predicted the 1-year risk of VF/SCA, based on age and these markers.

CONCLUSION

LMaxTpec and its association with pT1 and/or ER indicated elevated VF/SCA risk in adult patients with spontaneous BrT1. We successfully developed a simple risk prediction model based on age and these ECG markers.

Prognostic significance of a low T/R ratio in Brugada syndrome

OBJECTIVES

To determine the prognostic value of a low T/R ratio, defined as the amplitude ratio between the T waves and the R waves, in patients (pts) with a spontaneous type-1 Brugada pattern (SBT1).

BACKGROUND

Abnormalities of myocardial repolarization may play a key role in the initiation of ventricular fibrillation (VF) in Brugada syndrome (BrS). Recent studies have shown that the height of the T waves and the T/R ratio are inversely proportional to sudden cardiac arrest (SCA) risk in early repolarization syndrome and hypertrophic cardiomyopathy.

METHODS

In an international retrospective study, we reviewed 115 pts. (105 males, 91.3%). 45 had VF and/or SCA (38.7 ± 11.5 years old, all males), while 70 (49.3 ± 12.0 years, 10 women) remained free of ventricular arrhythmia. 6 ECG markers plus the T/R ratio in leads V5 & II were studied.

RESULTS

The T/R ratio among leads II & V5 was significantly lower in the VF/SCA group (0.24 [0.14; 0.38]vs. 0.34 [0.24; 0.45]; p = 0.006). 44.4% of pts. in the VF/SCA group had a lowest T/R ratio among leads II & V5 ≤ 0.17 compared to 11.4% in the non-VF/SCA group (p < 0.001). In multivariate analysis, a lowest T/R ratio among leads II & V5 ≤ 0.17 was independently associated with VF/SCA (OR 6.10, 95% CI 1.92-19.40; p = 0.002). Type 1 Brugada pattern in the peripheral leads (OR 10.78) and early repolarization (OR 3.60) were other independent markers of VF/SCA.

CONCLUSION

A low T/R ratio among leads II & V5 is an independent marker for VF/SCA risk in patients with type-1 Brugada pattern.

Impact of β-blocker therapy on right ventricular function in heart failure patients with reduced ejection fraction. A prospective evaluation

BACKGROUND

Beta-blocker (β-blocker) therapy has been shown to improve mortality and reduce hospitalizations in patients with heart failure (HF) with reduced ejection fraction (HFrEF). Although the physiological action mechanisms of β-blockers are well described, their effects on right ventricular (RV) function have not been prospectively studied.

OBJECTIVE

This prospective study aimed to (a) evaluate whether β-blocker therapy impacts RV remodeling based on echo parameters and (b) determine the predictive echo factors of β-blocker therapy response.

METHODS

From September 2017 to September 2018, HF patients were prospectively enrolled using CIBIS criteria: Class II, III, or IV HF; left ventricular ejection fraction (LVEF) of ≤40%; hospitalized for HF within the previous 12 months. Echo evaluation was performed before initiating β-blocker therapy and 3 months after optimal dose adjustment. Based on previous studies, patients with (absolute) LVEF ≥ 5% improvement were considered significant β-blocker therapy responders.

RESULTS

Overall, 40 patients (pts) completed the study, characterized as follows by age: 70 ± 10 years; gender: 10 women; cardiomyopathy etiology: idiopathic in 24 and ischemic in 16; NYHA Class: II in 22 and III in 10; LVEF: 32 ± 5%; and NTProBNP: 2665 ± 2400 pg/mL. The final population comprised 32 pts (79%), with eight (21%) excluded: two because of β-blocker therapy intolerance, one lost to follow-up, and five withdrew from the study. Under β-blocker therapy, several echo parameters significantly improved: LVEF from 31.7 ± 9 to 40.5 ± 9 (P < .0001); LV end-diastolic volume (EDV) from 154 ± 54 to 143 ± 45 mL (P = .06); LV end-systolic volume (ESV) from 107 ± 49 to 88 ± 37 mL (P = .0006); LV ES from 46 ± 11 to 64 ± 13 mL (P = .008); LV end-diastolic diameter (EDD) from 57 ± 9 to 54 ± 6 mm (P = .04); LV end-systolic diameter (ESD) from 48 ± 10 to 44 ± 7 mm (P = .007); and right ventricular systolic pressure (RV SP) from 39 ± 10 to 32 ± 8 mm Hg (P = .0001). Significant modifications were observed in terms of RV echo parameters: right ventricular (RV) size decreased from 30 ± 4 to 27 ± 5 mm (P = .03), while RV systolic function significantly improved based on tricuspid annular plane systolic excursion (TAPSE) (16.5 ± 4 vs. 19 ± 4 mm; 0.0006); DTI-derived tricuspid lateral annular systolic velocity wave (S') (10 ± 2 vs. 11.3 ± 3 cm/s; P = .03); and RIMP (Tei index) (0.5 ± 0.1 vs 0.46 ± 0.1; P = .04). RV 2D fractional area change (%) did not significantly differ despite a clear improvement tendency (35 ± 6 vs. 37 ± 4%; P = .1). No significant modifications were observed concerning LV diastolic parameters. Overall, β-blocker echo responders (n = 23/32; 72%) exhibited the same left and right echo parameters. No echo variables predicted the β-blocker response.

CONCLUSIONS

In HFrEF pts, β-blocker therapy significantly improves LV and RV systolic remodeling. Accordingly, β-blocker therapy could be applied as soon as possible in HFrEF patients with right ventricular dysfunction so as to limit RV remodeling.

Initial multicenter experience with a new high-density coloring module: impact for complex atrial arrhythmias interpretation

BACKGROUND

High-density automated mapping of complex atrial tachycardias (ATs) requires accurate assessment of activation maps. A new local activation display module (HD coloring, Biosense Webster®) provides higher map resolution, a better delineation of potential block reducing color interpolation, and a new propagation display. We evaluated the accuracy of a dedicated local activation display compared with standard algorithm.

METHODS

High-density maps from 10 AT were collected with a multipolar catheter and were displayed with standard activation or HD coloring. Six expert operators retrospectively analyzed activation maps and were asked to define (1) the tachycardia mechanism, (2) ablation target, and (3) level of difficulty to interpret those maps.

RESULTS

Using HD coloring, operators were able to reach a correct diagnosis in 93% vs. 63%, p < 0.05 compared to standard activation maps. Time to diagnosis was shorter 1.9 ± 1.0 min vs. 3.9 ± 2.1 min, p < 0.05. Confidence level would have allowed ablation without necessity for entrainment maneuvers in 87% vs. 53%, p < 0.05. Operators would have needed to remap or proceed with multiple entrainments in 3% vs. 13% of cases, p < 0.05. Finally, ablation strategy was more accurately identified in 97% vs. 67%, p < 0.05.

CONCLUSION

Activation mapping with the new HD coloring module allowed a more accurate, reliable, and faster interpretation of complex ATs mechanisms compared to standard activation maps.

An N-/L-type calcium channel blocker, cilnidipine, suppresses autonomic, electrical, and structural remodelling associated with atrial fibrillation

AIMS

Autonomic dysfunction can promote atrial fibrillation (AF) and results from AF-related remodelling. N-type Ca2+-channels (NTCCs) at sympathetic nerve terminals mediate Ca2+-entry that triggers neurotransmitter release. AF-associated remodelling plays an important role in AF pathophysiology but the effects of NTCC inhibition on such remodelling is unknown. Here, we investigated the ability of a clinically available Ca2+-channel blocker (CCB) with NTCC-blocking activity to suppress the arrhythmogenic effects of AF-promoting remodelling in dogs.

METHODS AND RESULTS

Mongrel dogs were kept in AF by right atrial tachypacing at 600 bpm. Four groups were studied under short-term AF (7 days): (i) Shams, instrumented but without tachypacing (n = 5); (ii) a placebo group, tachypaced while receiving placebo (n = 6); (iii) a control tachypacing group receiving nifedipine (10 mg orally twice-daily; n = 5), an L-type CCB; and (iv) a cilnidipine group, subjected to tachypacing and treatment with cilnidipine (10 mg orally twice-daily; n = 7), an N-/L-type CCB. With cilnidipine therapy, dogs with 1-week AF showed significantly reduced autonomic changes reflected by heart rate variability (decreases in RMSSD and pNN50) and plasma norepinephrine concentrations. In addition, cilnidipine-treated dogs had decreased extracellular matrix gene expression vs. nifedipine-dogs. As in previous work, atrial fibrosis had not yet developed after 1-week AF, so three additional groups were studied under longer-term AF (21 days): (i) Shams, instrumented without tachypacing or drug therapy (n = 8); (ii) a placebo group, tachypaced while receiving placebo (n = 8); (iii) a cilnidipine group, subjected to tachypacing during treatment with cilnidipine (10 mg twice-daily; n = 8). Cilnidipine attenuated 3-week AF effects on AF duration and atrial conduction, and suppressed AF-induced increases in fibrous-tissue content, decreases in connexin-43 expression and reductions in sodium-channel expression.

CONCLUSIONS

Cilnidipine, a commercially available NTCC-blocking drug, prevents AF-induced autonomic, electrical and structural remodelling, along with associated AF promotion.

Screening Rheumatic Heart Disease in 1530 New Caledonian Adolescents

BACKGROUND

In New Caledonia, a South Pacific archipelago whose inhabitants comprise Melanesians, Europeans/whites, Wallisians, Futunans, Polynesians, and Asians, the prevalence of rheumatic heart disease (RHD) is 0.9% to 1% at ages 9 and 10. It could be higher at the age of 16, but this remains to be verified.

METHODS AND RESULTS

A total of 1530 Melanesian, Métis, white, Wallisian, Futunan, Polynesian, and Asian adolescents benefited from a transthoracic echocardiogram. Definite or borderline RHD, nonrheumatic valve lesions, congenital heart defects, family and personal history of acute rheumatic fever, and socioeconomic factors were collected. The prevalence of cardiac abnormalities was 8.1%, made up of 4.1% RHD including 2.4% definite and 1.7% borderline RHD, 1.7% nonrheumatic valve lesions, and 2.3% congenital anomalies. In whites and Asians, there were no cases of RHD. RHD was higher in the Wallisian, Futunan, and Polynesian group (7.6%) when compared with Melanesians (5.3%) and Métis (2.9%). The number of nonrheumatic valve lesions was not statistically different in the different ethnicities. The prevalence of RHD was higher in adolescents with a personal history of acute rheumatic fever, in those living in overcrowded conditions, and in those whose parents were unemployed or had low‐income occupations, such as the farmers or manual workers.

CONCLUSIONS

RHD was 4 times higher in adolescents at age 16 than at ages 9 and 10 (4.1% versus 0.9%–1%). No cases of RHD were observed in whites and Asians. The determining factors were history of acute rheumatic fever and socioeconomic factors.

Adenosine usage during AF ablation in Europe and selected long-term findings from the ESC-EHRA EORP Atrial Fibrillation Ablation Long-Term registry

Background

Adenosine can be used to reveal dormant pulmonary vein (PV) conduction after PV isolation (PVI). This study presents a subanalysis of real-world 1-year follow-up data from the ESC-EHRA EORP Atrial Fibrillation (AF) Ablation Long-Term registry to analyze the usage of adenosine during PVI treatment in terms of rhythm outcome and safety.

Methods

The registry consists of 104 participating centers in 27 countries within the European Society of Cardiology. The registry data was split into an adenosine group (AG) and no-adenosine group (NAG). Procedure characteristics and patient outcome were compared.

Results

Adenosine was administered in 10.8% of the 3591 PVI patients included in the registry. Spain, the Netherlands, and Italy included the majority of adenosine cases (48.8%). Adenosine was applied more often in combination with open irrigation radiofrequency (RF) energy (74.7%) and less often in combination with nonirrigated RF energy (1.6%). After 1 year, a higher percentage of the AG was free from AF compared with the NAG (68.9% vs 59.1%, p < 0.001). Adenosine was associated with better rhythm outcome in RF ablation procedures, but not in cryo-ablation procedures (freedom from AF: RF: AG: 70.9%, NAG: 58.1%, p < 0.001, cryo: AG: 63.9%, NAG: 63.8%, p = 0.991).

Conclusions

The use of adenosine was associated with a better rhythm outcome after 1 year follow-up and seems more useful in patients treated with RF energy compared with patients treated with cryo energy. Given the improved rhythm outcome at 1-year follow-up, it seems reasonable to encourage the use of adenosine during RF AF ablation.

Cardiovascular disease events within 5 years after a diagnosis of breast cancer

BACKGROUND

Concern for cardiovascular disease (particularly atrial fibrillation-AF) among women with breast cancer is becoming a major issue. We aimed at determining the incidence of cardiovascular disease events (AF, arterial and cardiac events, venous-thromboembolism-VTE) in patients diagnosed with breast cancer, and assessing potential risk factors.

METHODS

We reviewed medical records of all patients diagnosed with breast cancer from 2010 to 2011 in our cancer center. Baseline characteristics of patients and tumors were collected. The main outcome was the occurrence of cardiovascular disease events (AF, VTE, arterial and cardiac events) during the 5-years follow-up.

RESULTS

Among the 682 breast cancer patients, 22 (3.2%) patients had a history of atrial fibrillation. Thirty-four patients (5%) presented at least one cardiovascular disease event, leading to a cumulative incidence of 5.8% events at 5-years ([3.8-7.7] CI 95%), with most of them occurring in the first 2 years. AF cumulative incidence was 1.1% ([0.1-2.1] CI 95%). Factors associated with the occurrence of cardiovascular disease events (including AF) were an overexpression of HER-2 (HR 2.6 [1.21-5.56] p < 0.011), UICC-stage III tumors or more (HR 5.47 [2.78-10.76] p < 0.001) and pre-existing cardiovascular risk factors (HR 2.91 [1.36-6.23] p < 0.004).

CONCLUSION

The incidence of cardiovascular disease events was 5.8% ([3.8-7.7] CI 95%), with HER-2 over-expression, UICC-stage III tumors or more and pre-existing cardiovascular diseases being associated with them. These findings call for the development of preventive strategies in patients diagnosed with breast cancer.

High Risk of Sustained Ventricular Arrhythmia Recurrence After Acute Myocarditis

Acute myocarditis is associated with cardiac arrhythmia in 25% of cases; a third of these arrhythmias are ventricular tachycardia (VT) or ventricular fibrillation (VF). The implantation of a cardiac defibrillator (ICD) following sustained ventricular arrhythmia remains controversial in these patients. We sought to assess the risk of major arrhythmic ventricular events (MAEs) over time in patients implanted with an ICD following sustained VT/VF in the acute phase of myocarditis compared to those implanted for VT/VF occurring on myocarditis sequelae. Our retrospective observational study included patients implanted with an ICD following VT/VF during acute myocarditis or VT/VF on myocarditis sequelae, from 2007 to 2017, in 15 French university hospitals. Over a median follow-up period of 3 years, MAE occurred in 11 (39%) patients of the acute myocarditis group and 24 (60%) patients of the myocarditis sequelae group. Kaplan–Meier MAE rate estimates at one and three years of follow-up were 19% and 45% in the acute group, and 43% and 64% in the sequelae group. Patients who experienced sustained ventricular arrhythmias during acute myocarditis had a very high risk of VT/VF recurrence during follow-up. These results show that the risk of MAE recurrence remains high after resolution of the acute episode.

Role of atrial arrhythmia and ventricular response in atrial fibrillation induced atrial remodelling

AIMS

No studies have assessed the specific contributions of atrial fibrillation (AF)-related atrial vs. associated ventricular arrhythmia to remodelling. This study assessed the roles of atrial arrhythmia vs. high ventricular rate in AF-associated remodelling.

METHODS AND RESULTS

Four primary dog-groups (12/group) were subjected to 3-week pacing: 600-b.p.m. atrial tachypacing maintaining AF [AF w/o- atrioventricular block (AVB)]; atrial tachypacing with atrioventricular-node ablation (AF+AVB) and ventricular-demand pacing (80 b.p.m.); 160-b.p.m. ventricular-tachypacing (V160) reproducing the response rate during AF; and sinus rhythm with AVB/ventricular-pacing at 80-b.p.m. (control group). At terminal study, left-atrial (LA) effective refractory period (ERP) was reduced equally in both AF groups (w/o-AVB and AF+AVB). AF-inducibility was increased strongly in AF groups (w/o-AVB and AF+AVB) and modestly in V160. AF duration was significantly increased in AF w/o-AVB but not in AF+AVB or V160. Conduction velocity was decreased in AF w/o-AVB, to a greater extent than in AF+AVB and V160. Atrial fibrous-tissue content was increased in AF w/o-AVB, AF+AVB and V160, with collagen-gene up-regulation only in AF w/o-AVB. Connexin43 gene expression was reduced only in AF w/o-AVB. An additional group of 240-b.p.m. ventricular tachypacing dogs (VTP240; to induce heart failure) was studied: vs. other tachypaced groups, VTP240 caused greater fibrosis, but no change in LA-ERP or AF-inducibility. VTP240 also increased AF duration, strongly decreased left ventricular ejection fraction, and was the only group with LA natriuretic-peptide activation.

CONCLUSION

The atrial tachyarrhythmia and rapid ventricular response during AF produce distinct atrial remodelling; both contribute to the arrhythmogenic substrate, providing new insights into AF-related remodelling and novel considerations for ventricular rate-control.

The European Society of Cardiology Cardiac Resynchronization Therapy Survey II: A comparison of cardiac resynchronization therapy implantation practice in Europe and France

BACKGROUND

The first European Cardiac Resynchronization Therapy (CRT) Survey, conducted in 2008-2009, showed considerable variations in guideline adherence and implantation practice. A second prospective survey (CRT Survey II) was then performed to describe contemporary clinical practice regarding CRT among 42 European countries.

AIM

To compare the characteristics of French CRT recipients with the overall European population of CRT Survey II.

METHODS

Demographic and procedural data from French centres recruiting all consecutive patients undergoing either de novo CRT implantation or an upgrade to a CRT system were collected and compared with data from the European population.

RESULTS

A total of 11,088 patients were enrolled in CRT Survey II, 754 of whom were recruited in France. French patients were older (44.7% aged≥75 years vs 31.1% in the European group), had less severe heart failure symptoms, a higher baseline left ventricular ejection fraction and fewer co-morbidities. Additionally, French patients had a shorter intrinsic QRS duration (19.1% had a QRS<130ms vs 12.3% in the European cohort). Successful implantation rates were similar, but procedural and fluoroscopy times were shorter in France. French patients were more likely to receive a CRT pacemaker than European patients overall. Of note, antibiotic prophylaxis was reported to be administered less frequently in France, and a higher rate of early device-related infection was observed. Importantly, French patients were less likely to receive optimal drugs for treating heart failure at hospital discharge.

CONCLUSION

This study highlights contemporary clinical practice in France, and describes substantial differences in patient selection, implantation procedure and outcomes compared with the other European countries participating in CRT Survey II.

Impact of sacubitril/valsartan on echo parameters in heart failure patients with reduced ejection fraction a prospective evaluation

Background

Sacubitril/valsartan has been shown to improve mortality and reduce hospitalizations in patients with heart failure (HF) with reduced ejection fraction (HFrEF). Although the physiological action mechanisms of sacubitril/valsartan are well described, its effects on left ventricular (LV) remodelling and other echocardiographic (echo) parameters have not been prospectively studied.

Objective

The aim of this prospective study was to: McMurray et al. (2012) [1] evaluate if sacubitril/valsartan impacts LV remodelling based on echo parameters; Ponikowski et al. (2016) [2] identify the predictive factors of sacubitril/valsartan response or intolerance.

Methods

From May 2017 to September 2018, 52 HF patients were prospectively enrolled using PARADIGM-HF criteria: Class II, III, or IV HF; ejection fraction (EF) of 40% or less; hospitalized for HF within the previous 12 months. Echo evaluation was performed before initiating sacubitril/valsartan and 3 months after optimal dose adjustment. Based on previous studies, patients with (absolute) improvement in left ventricular ejection fraction (LVEF) ≥ 5% were considered significant sacubitril/valsartan responders.

Results

The 52 patients completing the study were characterized by age: 70 ± 10 years; gender: 11women; aetiology: idiopathic in 20 and ischaemic in 32; NYHA Class: II in 17 and III in 35; LVEF: 32 ± 5%; NTProBNP: 1805 ± 1914 pg/mL. The final population comprised 41 pts (79%), as 11 (21%) did not tolerate sacubitril/valsartan therapy. Under sacubitril/valsartan, several echo parameters significantly improved: LVEF from 32.6 ± 5 to 36 ± 6% (p < 0.0001); LVES volume from 117 ± 40 to 108 ± 46 mL (p = 0.0051); SEV from 59 ± 12 to 64 ± 13 (p = 0.0061); LVEDD from 60 ± 4 to 57 ± 5 mm (p = 0.0002); mean right ventricular systolic pressure (RVSP) from 39 ± 10 to 32 ± 8 (p = 0.0001). No significant modifications were observed concerning LV diastolic parameters or RV echo parameters. Sacubitril/valsartan echo responders (n = 18/41; 42%) had less severe LV remodelling, as shown by LVEDV: 144 ± 37 vs. 193 ± 47 mL, p = 0.0009; LVESV: 96 ± 28 vs. 133 ± 42 mL; p = 0.003; LVTDD: 61 ± 4 vs. 57 ± 5 mm; p = 0.02; significant mitral regurgitation: 6/18 (33%) vs. 16/23 (69%), p = 0.02; no diastolic LV or RV parameters impacted sacubitril/valsartan response. Predictors of sacubitril/valsartan intolerance were baseline creatinine level: 137 ± 99 vs. 100 ± 24, p = 0.03; LVEF: 29 ± 6 vs. 33 ± 5%; p = 0.04.

Conclusions

In HFrEF patients, sacubitril/valsartan significantly improves LV systolic remodelling, without any significant effects on LV diastolic or RV systolic echo parameters. Sacubitril/valsartan responders exhibit both less severe LV remodelling and less significant mitral regurgitation. Accordingly, sacubitril/valsartan could be used as soon as possible in HFrEF patients in order to limit LV remodelling, while precluding non-response or intolerance.

Device complications with addition of defibrillation to cardiac resynchronisation therapy for primary prevention

OBJECTIVE

In patients indicated for cardiac resynchronisation therapy (CRT), the choice between a CRT-pacemaker (CRT-P) versus defibrillator (CRT-D) remains controversial and indications in this setting have not been well delineated. Apart from inappropriate therapies, which are inherent to the presence of a defibrillator, whether adding defibrillator to CRT in the primary prevention setting impacts risk of other acute and late device-related complications has not been well studied and may bear relevance for device selection.

METHODS

Observational multicentre European cohort study of 3008 consecutive patients with ischaemic or non-ischaemic dilated cardiomyopathy and no history of sustained ventricular arrhythmias, undergoing CRT implantation with (CRT-D, n=1785) or without (CRT-P, n=1223) defibrillator. Using propensity score and competing risk analyses, we assessed the risk of significant device-related complications requiring surgical reintervention. Inappropriate shocks were not considered except those due to lead malfunction requiring lead revision.

RESULTS

Acute complications occurred in 148 patients (4.9%), without significant difference between groups, even after considering potential confounders (OR=1.20, 95% CI 0.72 to 2.00, p=0.47). During a mean follow-up of 41.4±29 months, late complications occurred in 475 patients, giving an annual incidence rate of 26 (95% CI 9 to 43) and 15 (95% CI 6 to 24) per 1000 patient-years in CRT-D and CRT-P patients, respectively. CRT-D was independently associated with increased occurrence of late complications (HR=1.68, 95% CI 1.27 to 2.23, p=0.001). In particular, when compared with CRT-P, CRT-D was associated with an increased risk of device-related infection (HR 2.10, 95% CI 1.18 to 3.45, p=0.004). Acute complications did not predict overall late complications, but predicted device-related infection (HR 2.85, 95% CI 1.71 to 4.56, p<0.001).

CONCLUSIONS

Compared with CRT-P, CRT-D is associated with a similar risk of periprocedural complications but increased risk of long-term complications, mainly infection. This needs to be considered in the decision of implanting CRT with or without a defibrillator.

Prevalence of Factor V Leiden in Patients with Myocardial Infarction and Normal Coronary Angiography

Factor V Leiden is associated with an increased risk of venous thrombosis and myocardial infarction in young women, but not in men in this latter case. The aim of this study was to evaluate the prevalence of this mutation in patients with myocardial infarction but normal coronary angiography.

We compared 3 groups of patients: one group consisted of 107 patients with premature myocardial infarction but no significant coronary artery stenosis; another group of 244 patients with myocardial infarction and significant coronary artery stenosis; a third group of 400 healthy controls.

Factor V Leiden was found in 13 patients (12.1%) who had a myocardial infarction without significant coronary artery stenosis, 11 patients (4.5%) who had a myocardial infarction with significant coronary artery stenosis (p = 0.01) and in 20 controls (5%) (p = 0.01). Odds ratio associated with factor V Leiden were respectively 2.93 (CI95 : 1.18-7.31) and 2.63 (CI95 : 1.19-5.78) when we compared myocardial infarction patients without significant coronary artery stenosis to controls or to patients with significant coronary artery stenosis.

In myocardial infarction patients without significant coronary artery stenosis, prevalence of factor V Leiden is significantly higher than in controls. This new finding supports the hypothesis that thrombosis plays a key role in this selected situation.

Assessment of cardiac resynchronisation therapy in patients with wide QRS and non-specific intraventricular conduction delay: rationale and design of the multicentre randomised NICD-CRT study

INTRODUCTION

Cardiac resynchronisation therapy (CRT) was initially developed to treat patients with left bundle branch block (LBBB). However, many patients with heart failure have a widened QRS but neither left-BBB nor right-BBB; this is called non-specific intraventricular conduction delay (NICD). It is unclear whether CRT is effective in this subgroup of patients.

METHODS AND ANALYSIS

The NICD-CRT study is a prospective, double-blind, randomised (1:1), parallel-arm, multicentre trial comparing the effects of CRT in patients with heart failure, a reduced left ventricular ejection fraction (LVEF <35%) and NICD, who have been implanted with a device (CRT-pacemaker or CRT-defibrillator) that has or has not been activated. Enrolment began on 15 July 2015 and should finish within 3 years; 40 patients have already been randomised and 11 centres have agreed to participate. The primary end point is the comparison of the proportion of patients improved, unchanged or worsened over the subsequent 12 months. 100 patients per group are required to demonstrate a difference between groups with a statistical power of 90%, a type I error of 0.05% (two-sided) and a loss to follow-up of 10%. This trial will add substantially to the modest amount of existing data on CRT in patients with NICD and should reduce uncertainty for guidelines and clinical practice when added to the pool of current information.

ETHICS AND DISSEMINATION

Local ethics committee authorisations have been obtained since May 2015. We will publish findings from this study in a peer-reviewed scientific journal and present results at national and international conferences.

TRIAL REGISTRATION NUMBER

NCT02454439; pre-results.

Prognosis assessment of persistent left bundle branch block after TAVI by an electrophysiological and remote monitoring risk-adapted algorithm: rationale and design of the multicentre LBBB-TAVI Study

INTRODUCTION

Percutaneous aortic valve replacement (transcatheter aortic valve implantation (TAVI)) notably increases the likelihood of the appearance of a complete left bundle branch block (LBBB) by direct lesion of the LBB of His. This block can lead to high-grade atrioventricular conduction disturbances responsible for a poorer prognosis. The management of this complication remains controversial.

METHOD AND ANALYSIS

The screening of LBBB after TAVI persisting for more than 24 hours will be conducted by surface ECG. Stratification will be performed by post-TAVI intracardiac electrophysiological study. Patients at high risk of conduction disturbances (≥70 ms His-ventricle interval (HV) or presence of infra-Hisian block) will be implanted with a pacemaker enabling the recording of disturbance episodes. Those at lower risk (HV <70 ms) will be implanted with a loop recorder device with remote monitoring of cardiovascular implantable electronic devices (CIEDs). Clinical, ECG and implanted device follow-up will also be performed at 3, 6 and 12 months. The primary objective is to assess the efficacy and safety of a decisional algorithm based on electrophysiological study and remote monitoring of CIEDs in the prediction of high-grade conduction disturbances in patients with LBBB after TAVI. The primary end point is to compare the incidence (rate and time to onset) of high-grade conduction disturbances in patients with LBBB after TAVI between the two groups at 12 months. Given the proportion of high-grade conduction disturbances (20-40%), a sample of 200 subjects will allow a margin of error of 6-7%. The LBBB-TAVI Study has been in an active recruiting phase since September 2015 (21 patients already included).

ETHICS AND DISSEMINATION

Local ethics committee authorisation was obtained in May 2015. We will publish findings from this study in a peer-reviewed scientific journal and present results at national and international conferences.

TRIAL REGISTRATION NUMBER

NCT02482844; Pre-results.

Robotic magnetic navigation for ablation of human arrhythmias

Radiofrequency treatment represents the first choice of treatment for arrhythmias, in particular complex arrhythmias and especially atrial fibrillation, due to the greater benefit/risk ratio compared to antiarrhythmic drugs. However, complex arrhythmias such as atrial fibrillation require long procedures with additional risks such as X-ray exposure or serious complications such as tamponade. Given this context, the treatment of arrhythmias using robotic magnetic navigation entails a technique well suited to complex arrhythmias on account of its efficacy, reliability, significant reduction in X-ray exposure for both patient and operator, as well as a very low risk of perforation. As ongoing developments will likely improve results and procedure times, this technology will become one of the most modern technologies for treating arrhythmias. Based on the literature, this review summarizes the advantages and limitations of robotic magnetic navigation for ablation of human arrhythmias.