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 multicentre 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 centres in 35 countries. In 78 centres 138 patients [0.025%, radiofrequency: 0.038%, cryoballoon: 0.0015% (P < 0.0001)] were diagnosed with an oesophageal fistula. Peri-procedural 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]. CONCLUSION: 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.

Benefits and outcomes of a new multidisciplinary approach for the management and financing of sudden unexplained death cases in a forensic setting in Switzerland.

Sudden cardiac death (SCD) is an important public health issue. In young persons aged between 1 and 40 years, most SCDs are caused by potentially inherited cardiac diseases, often not detectable during conventional medico-legal investigations and therefore termed as sudden unexplained deaths (SUD). In this study, we describe the implementation, feasibility and importance of a standardized procedure to investigate SUD cases within the forensic framework at the Zurich Institute of Forensic Medicine in Switzerland. This new approach involves a multidisciplinary collaboration including forensic autopsy, second pathology expert opinion, post-mortem molecular genetic testing, cardiac counselling of relatives, and a tentative financing. This procedure is in line with the published Swiss and European recommendations on the management of SCDs. During a two-year pilot project, 39 sudden and unexpected death cases were collected, whereof 10 deceased remained without any identifiable cause of death after medico-legal investigation and second expert evaluation. Molecular autopsy, including 393 genes involved in cardio-vascular and metabolic diseases, identified eight pathogenic or likely pathogenic genetic variants in five out of the 10 deceased (50%). Cardio-genetic follow-up investigations in the families of the 10 deceased revealed phenotype-positive relatives in four families and required specific therapies, including an implantable cardioverter defibrillator (ICD) for primary prevention. Multidisciplinary collaboration is crucial for an optimal management of sudden unexplained death cases, to identify additional relatives at risk, and to prevent other tragic deaths within a family.

Clinical impact of low coverage in whole-exome genetic testing in the assessment of familial arrhythmogenic right ventricular cardiomyopathy: a case report.

Background: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited condition, with approximately 60% of patients carrying a possibly disease-causing genetic variant. Known desmosomal genes account for about 50% of those variants. We herein report a family with ARVC in which a pathogenic desmosomal variant was missed because of the initial genetic testing method. Case summary: A 54-year-old man diagnosed with ARVC underwent genetic cascade screening for a heterozygous titin variant (TTN: c.26542C>T), detected in his phenotypically affected sister. He did not harbour this TTN variant. Moreover, reclassification of this variant based on the American College of Medical Genetics (ACMG) 2015 criteria showed it to be likely benign. Upon genetic re-screening with a dedicated cardiomyopathy panel a heterozygous missense variant in desmoglein-2 (DSG2: c.152G>C) was found. His sister's DNA was re-analysed and the same DSG2 variant was detected, and classified as LP (likely pathogenic) by current literature. Discussion: The initial genetic screening tool used in the patient's sister (whole-exome sequencing, WES) failed to detect the likely causative desmosomal variant in our family. While WES represents a good tool in searching for novel genes in Trio Analysis, it has a low DNA coverage in important regions (mean 10×) of known ARVC-associated genes. We therefore propose using smaller panels with better coverage in the clinical setting, such as Trusight-cardio (mean DNA coverage 100-300×) as an initial genetic screening method.

Assessment of injury current during leadless pacemaker implantation.

BACKGROUND: Leadless pacemakers are an established treatment option for bradyarrhythmias. Similar to conventional transvenous pacemakers, satisfying pacing values during implantation are targeted for optimal long-term device function. The objective is to investigate the role of a local injury current (IC) in leadless pacemaker implantations. METHOD: The IC, sensing value, capture threshold and impedance were collected in 30 consecutive patients receiving a leadless pacemaker. RESULTS: 39 EGMs were recorded from 30 patients (including 9 device repositions). An IC was detected in 15 cases (38%). At implantation, the presence of an IC was associated with a significantly lower sensing (7.1 ± 3.7 mV vs 12.0 ± 4.0 mV; P = 0.004) and a higher capture threshold (median threshold 1.13 V at 0.24 ms [0.50-2.00] vs 0.50 V at 0.24 ms [0.25-0.75]; P = 0.002) and with a 26 fold higher likelihood of device repositioning compared to the absence of an IC (OR 26.3 [2.79-248], P < 0.001). Patients with an IC in their final implant position had a lower sensing (9.3 ± 4.4 mV vs 13.6 ± 4.7 mV at implantation, P = 0.04), while the initially similar capture threshold was lower after 24 h in the IC group. After 2 weeks, all parameters were similar between the two groups. CONCLUSIONS: Our study shows that an IC can readily be observed during leadless pacemaker implantation associated with a lower sensing and a higher capture threshold at implantation but with similar to even better values during follow-up.

High interobserver variability in the assessment of epsilon waves: Implications for diagnosis of arrhythmogenic right ventricular cardiomyopathy/dysplasia.

BACKGROUND: Revision of the Task Force diagnostic criteria for arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) has increased their sensitivity for the diagnosis of early and familial forms of the disease. The epsilon wave is a major diagnostic criterion in the context of ARVC/D, which, however, remains not quantifiable and therefore may leave room for substantial subjective interpretation. OBJECTIVE: The purpose of this study was to assess interobserver agreement in epsilon wave definition and epsilon wave importance for ARVC/D diagnosis. METHODS: Electrocardiographic (ECG) tracings depicting leads V1, V2, and V3 collected from individuals evaluated for ARVC/D (n = 30) were given to panel members who were asked to respond to the question whether ECG patterns meet epsilon wave definition outlined by the Task Force diagnostic criteria. The prevalence and importance of epsilon waves for ARVC/D diagnosis were assessed in a pooled data set of patients with definite ARVC/D from European and American registries (n = 815). RESULTS: The number of ECG patterns identified as epsilon waves varied from 5 to 18 per reviewer (median 13 per reviewer). A unanimous agreement was reached for only 10 cases (33%), 2 of which qualified as epsilon waves and 8 as non-epsilon waves by all panel members. From a pooled data set, 106 patients reportedly had epsilon waves (13%). In 105 of 106 patients with epsilon waves (99%), exclusion of epsilon waves from the diagnostic score would not affect the "definite" diagnostic category. CONCLUSION: Interobserver variability in the assessment of epsilon waves is high; however, the impact of epsilon waves on ARVC/D diagnosis is negligibly low. The results urge to exercise caution in the assessment of epsilon waves, especially in patients who would not otherwise meet diagnostic criteria.