Risk Factors for Incident Polycystic Ovary Syndrome Diagnosis

Objective: While highly prevalent, risk factors for incident polycystic ovary syndrome (PCOS) are poorly delineated. Using a population-based cohort, we sought to identify predictors of incident PCOS diagnosis. Materials and Methods: A matched case-control analysis was completed utilizing patients enrolled in Kaiser Permanente Washington from 2006 to 2019. Inclusion criteria included female sex, age 16-40 years, and ≥3 years of prior enrollment with ≥1 health care encounter. PCOS cases were identified using International Classification of Diseases codes. For each incident case (n = 2,491), 5 patients without PCOS (n = 12,455) were matched based on birth year and enrollment status. Potential risk factors preceding diagnosis included family history of PCOS, premature menarche, parity, race, weight gain, obesity, valproate use, metabolic syndrome, epilepsy, prediabetes, and types 1 and 2 diabetes. Potential risk factors for incident PCOS diagnosis were assessed with univariate and multivariable conditional logistic regressions. Results: Mean age of PCOS cases was 26.9 years (SD 6.8). PCOS cases, compared with non-PCOS, were more frequently nulliparous (70.9% versus 62.4%) and in the 3 years prior to index date were more likely to have obesity (53.8% versus 20.7%), metabolic syndrome (14.5% versus 4.3%), prediabetes (7.4% versus 1.6%), and type 2 diabetes (4.1% versus 1.7%) (p < 0.001 for all comparisons). In multivariable models, factors associated with higher risk for incident PCOS included the following: obesity (compared with nonobese) Class I-II (body-mass index [BMI], 30-40 kg/m2; odds ratio [OR], 3.8; 95% confidence interval [CI], 3.4-4.2), Class III (BMI > 40 kg/m2; OR, 7.5, 95% CI, 6.5-8.7), weight gain (compared with weight loss or maintenance) of 1-10% (OR, 1.7, 95% CI, 1.3-2.1), 10-20% (OR, 1.9; 95% CI, 1.5-2.4), and >20% (OR, 2.6; 95% CI, 1.9-3.6), prediabetes (OR, 2.7; 95% CI, 2.1-3.4), and metabolic syndrome (OR, 1.8: 95% CI, 1.5-2.1). Conclusion: Excess weight gain, obesity, and metabolic dysfunction may play a key role in the ensuing phenotypic expression of PCOS. Treatment and prevention strategies targeted at preventing weight gain in early reproductive years may help reduce the risk of this syndrome.

Incidence, prevalence, and trends in polycystic ovary syndrome diagnosis: a United States population-based study from 2006 to 2019

BACKGROUND

Polycystic ovary syndrome is the most common endocrine disorder in women of reproductive age, yet US incidence estimates do not exist, and prevalence estimates vary widely.

OBJECTIVE

A population-based US study estimated the incidence, prevalence, and trends of polycystic ovary syndrome by age, race and ethnicity, and diagnosing provider type.

STUDY DESIGN

A retrospective cohort study of patients enrolled in Kaiser Permanente Washington from 2006 to 2019 was conducted. All members identified as female, aged 16 to 40 years with at least 3 years of enrollment and at least 1 healthcare encounter during that time, were eligible for inclusion. Individuals were excluded if they had a history of oophorectomy or hysterectomy. Polycystic ovary syndrome cases were identified using the International Classification of Diseases diagnosis codes (International Classification of Diseases, Ninth Revision, 256.4 or International Classification of Diseases, Tenth Revision, E28.2). Individuals with a polycystic ovary syndrome diagnosis before study entry were excluded from incidence rate estimations. The incidence rates were adjusted by age using direct standardization to the 2010 US census data. Temporal trends in incidence were assessed using weighted linear regression (overall) and Poisson regression (by age, race and ethnicity, and provider type). Prevalent cases were defined as patients with a polycystic ovary syndrome diagnosis at any time before the end of 2019. Medical record review of 700 incident cases diagnosed in 2011-2019 was performed to validate incident cases identified by International Classification of Diseases codes using the Rotterdam criteria.

RESULTS

Among 177,527 eligible patients who contributed 586,470 person-years, 2491 incident polycystic ovary syndrome cases were identified. The mean age at diagnosis was 26.9 years, and the mean body mass index was 31.6 kg/m2. Overall incidence was 42.5 per 10,000 person-years; the rates were similar over time but increased in individuals aged 16 to 20 years from 31.0 to 51.9 per 10,000 person-years (P=.01) and decreased among those aged 26 to 30 years from 82.8 to 45.0 per 10,000 person-years (P=.02). A small decreasing temporal trend in incidence rates was only observed among non-Hispanic White individuals (P=.01). The incidence rates by diagnosing provider type varied little over time. Among the 58,241 patients who contributed person-time in 2019, 3036 (5.2%) had a polycystic ovary syndrome International Classification of Diseases diagnosis code; the prevalence was the highest among the Hawaiian and Pacific Islander group (7.6%) followed by Native American and Hispanic groups. Medical record review classified 60% as definite or probable incident, 14% as possible incident, and 17% as prevalent polycystic ovary syndrome. The overall positive predictive value of polycystic ovary syndrome International Classification of Diseases diagnosis code for identifying definite, probable, or possible incident polycystic ovary syndrome was 76% (95% confidence interval, 72%-79%).

CONCLUSION

Among a cohort of nonselected females in the United States, we observed stable rates of incident polycystic ovary syndrome diagnoses over time. The incidence of polycystic ovary syndrome was 4- to 5-fold greater than reported for the United Kingdom. The prevalence of polycystic ovary syndrome (5.2%) was almost double before the published US estimates (2.9%) based on the International Classification of Diseases codes. Race and ethnicity and provider type did not seem to have a major impact on temporal rates. Incident diagnoses increased over time in younger and decreased in older age groups, perhaps related to shifting practice patterns with greater awareness among practitioners of the impact of polycystic ovary syndrome on long-term health outcomes and improved prevention efforts. Moreover, increasing obesity rates may be a factor driving the earlier ages at diagnosis.

Water quality of The Gambia River: A prospective drinking water supply

Drinking water in The Gambia is mostly derived from boreholes that could potentially be contaminated. The Gambia River, a major river in West Africa that covers 12 % of the country's area, could be more exploited for drinking water supply. During the dry season, the total dissolved solids (TDS), ranging from 0.02 to 33 g/L in The Gambia River, decreases with the distance to the river mouth with no major inorganic contamination. The freshwater (<0.8 g/L TDS) starts from Jasobo at approximately 120 km from the river mouth and extends by about 350 km to the eastern border of The Gambia. With a dissolved organic carbon (DOC) ranging from 2 to 15 mgC/L, the natural organic matter (NOM) of The Gambia River was characterised by 40-60 % humic substances of paedogenic origin. With such characteristics, unknown disinfection by-products could be formed if chemical disinfection, such as chlorination, was implemented during treatment. Out of 103 types of micropollutants, 21 were detected (4 pesticides, 10 pharmaceuticals, 7 per- and polyfluoroalkyl substances (PFAS)) with concentrations ranging from 0.1 to 1500 ng/L. Pesticides, bisphenol A and PFAS concentrations were below the stricter EU guidelines set for drinking water. These were mainly confined to the urban area of high population density near the river mouth, while the quality of the freshwater region of low population density was surprisingly pristine. These results indicate that The Gambia River, especially in its upper regions, would be well suited as a drinking water supply when using decentralised ultrafiltration treatment for the removal of turbidity, as well as, depending on pore size, to a certain extent microorganisms and DOC.

Characteristics and prognosis of the catecholamine induced QT prolongation syndrome

Background

We have recently demonstrated association of unexplained sudden cardiac arrest (SCA) with inheritance of catecholamine induced QT prolongation (CIQTP).

Objective

We here aim to describe incidence, characteristics and prognosis of this new syndrome in young patients with unexplained SCA or their relatives.

Methods

We reviewed the medical screening of all consecutive patients or their first-degree relatives explore from 2015 after the occurrence of a SCA before age 45. Structural heart disease or inherited arrhythmia diseases were excluded. A mental stress test was performed, as previously described, for each family members. All families with a positive mental stress were included in the study. Genetic screening was performed in at least one positive patient per family using targeted sequencing on a panel of 109 genes associated with inherited arrhythmias and cardiomyopathies.

Results

Among 456 patients screened (24 after SCA, 432 for familial screening) of 153 families, we identified 10 families (6.5%) with a catecholamine induced QT prolongation. No mutation was identified in these families. One hundred and ten patients were screened in CIQTP families. Thirty-four patients (30.9%) presented a CIQTP (mean age 42±20 yo, 64.7% of women). Five (14.7%) patients presented with previous symptoms (including 4 syncope and 1 SCA).

Two patients (5.9%) were implanted with an ICD and eleven (32.3%) were treated with beta blocker therapy mainly because of QT prolongation &gt;500 ms after mental stress test or previous symptoms.

After a 3.6±1.8 years of follow up, no sudden cardiac death nor syncope occurred on beta blocker therapy except for one patient implanted with an ICD after a SCA. Under beta blocker treatment the patient was asymptomatic for 5 years. After a suddenly stop of the beta blocker treatment, the patient underwent VF. For 3 years now the patient is asymptomatic under beta blocker treatment.

Conclusions

In our experience, CIQTP families represent 6.5% of cases of unexplained SCD and suggest systematic screening with a mental stress test for family screening after the occurrence of a SCA. Beta blocker therapy is very efficient to reduce the risk of SCA.

Funding Acknowledgement

Type of funding sources: None.

SCN5A mutations and the role of genetic background in the pathophysiology of Brugada syndrome

Background

Mutations in SCN5A are identified in approximately 20% to 30% of probands affected by Brugada syndrome (BrS). However, in familial studies, the relationship between SCN5A mutations and BrS remains poorly understood. The aim of this study was to investigate the association of SCN5A mutations and BrS in a group of large genotyped families.

Methods

Families were included if at least 3 family members were carriers of the SCN5A mutation, which was identified in the proband. Families were recruited from 12 tertiary centers in France between 1995 and 2020. Type 1 ST elevation was defined by ≥2 mm J-point elevation with coved ST segment and negative T wave.

Results

Forty-nine large families composed of 600 members including 304 mutation carriers (51%) were studied. The signature type I ECG was present in 160 mutation carriers (BrS-ECG+; 53%). In 42 families, we found 33 individuals affected by BrS but with a negative genotype (mutation-negative BrS-ECG+). Among them, 5 patients have an ECG suggestive of BrS but without the complete signature type I ECG. Among these 33 mutation-negative BrS-ECG+ individuals, 3 (9%), belonging to 3 different families, had a spontaneous type I ECG, whereas 28 had a type I ECG only after the administration of sodium channel blockers. Three of these 33 individuals (9%) had also experienced syncope. Mutation carriers had, on average, longer PR (190±36 ms vs 154±29 ms, p&lt;0.0001) and QRS (107±19 vs 92±29 ms, p&lt;0.0001) intervals than noncarriers, demonstrating that these mutations exerted functional effects.

Conclusions

Our results suggest that SCN5A mutations are not directly causal to the occurrence of a BrS-ECG+ and that genetic background may play a powerful role in the pathophysiology of BrS. These findings are consistent with the notion that the pathophysiology of BrS includes various elements beyond mutant sodium channels.

Funding Acknowledgement

Type of funding sources: None.

Current practices and expectations to reduce Electrophysiology catheters environmental impact: a large EHRA/LIRYC European survey

Funding Acknowledgements

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Boston Scientific

Background

Despite aiming at improving patients’ health, healthcare consumes a large amount of resources and contributes to 4.6% of the global GHG/carbon emissions, 71% of the footprint being due the supply chain. It also produces millions of tons of complex waste per year. Yet, sustainability in EP remains a complex challenge as the performance and safety for patients are critical.

Objective

To set the ground to reduce electrophysiology (EP) catheters’ environmental impact.

Methods

A survey was conducted to poll European EP centers on 24 questions on sustainability practices and expectations.

Results

278, mostly EP doctors (84%, 76% male, 43yo), working in a public environment (89%, &gt;100 procedures/year in 53% and &gt; 500 in 36%) participated. A majority of EP doctors uses 2 to 4 more catheters/sheath per paroxysmal AF ablation procedure. MAPPING/ABLATION catheters are discarded after the procedure (73&78%), with partial re-cycling (electrodes) in 23&26 %. Local/external sterilization is rarely used (12% & 9%).

Catheters’ packaging are discarded in medical or general waste (38 & 31%) while it is recycled in only 19%.

EP Healthcare professionals are highly motivated in being environment friendly in their personal (82%) and in EP practice (62%). They identify a lack of interest from their hospital in 59% (only 16% having an executive in charge). Other barriers are the complexity of sustainability processes (48%), the effort required to change practice (47%), infectious risk (41%), lack of training (37%) and cost (33%). EP Healthcare professionals would favor sustainable mapping /ablation catheters if performances were preserved (60 & 50%). They consider re-use as the most relevant solution (60%) while being currently illegal in some European countries. Packaging should be reduced in size or made reusable. Finally, they consider that regulatory (31%), education (19%) and recommendations by companies (19%) would encourage the field to transition to more environmentally friendly practices. Interestingly, age, gender, type of practice, country or experience did not impact the results.

Conclusion

EP Healthcare professionals demonstrate a willingness to adopt sustainable practices. They consider re-use as the most relevant approach as of today. 60/50 % would favour sustainable mapping/ablation catheters providing preserved performances. Leaping to the next level of sustainability will request development of new sustainable solutions, models and technologies. Reaching this urgent goal will require governments, industry, hospitals and doctors to work closely in a coordinated approach.

Multimodality planning of stereotactic radio-ablation for ventricular tachycardia. Results from the international MUSIC consortium

Funding Acknowledgements

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): European Research Council

Background

Optimal SBRT planning methods for VT ablation are yet to be defined.

Purpose

To evaluate a multimodal approach for SBRT planning.

Methods

30 pts (age 70±10, 90% men, LVEF 26±9%, 67% ICM, 47% NICM or mixed, 1.7±1.2 prior catheter ablations) with drug-refractory VT underwent imaging prior to SBRT. The inHEART technology was used to create image-based 3D models of substrate, cardiac anatomy, and organs at risk (coronaries, phrenic nerve, GI tract, AV node). In MUSIC software (IHU Liryc-Inria), 3D models were fused with prior EP maps, and SBRT targets were interactively drawn in 3D by the referring EP cardiologist. Transmural target volumes and organs at risk were fused with a 4D planning CT and used to plan SBRT in Eclipse (Varian).

Results

SBRT was delivered on median PTVs of 96[63-149] mL (total dose 25 Gy) with either Truebeam or Edge systems (Varian). Over a median FU of 4[2-8] months, death occurred in 11(37%) pts, due to arrhythmia recurrence in 4(13%). FU at 6 months was available in 14 pts. In these, the median numbers of VT episodes and ICD shocks over the 6 months preceding SBRT were 20[9-27] and 8[5-15], respectively. In the 6 months following SBRT, these decreased to 0[0-30] and 0[0-0], respectively (P&lt;0.001 for both). 8/14(57%) pts were free from any VT recurrence, and 11/14(79%) were free from any ICD shock. In the total cohort, complications attributed to SBRT were observed in 2/30 (7%), none of which were fatal (heart failure and pneumonitis, both managed with steroids).

Conclusion

In patients with severe drug- and catheter ablation-refractory VT, SBRT planning based on 3D image-based models fused with prior EP maps is feasible, and associated with favorable efficacy and safety profiles.

Up-to-date monitoring data of wastewater and stormwater quality in Germany

A comprehensive dataset of pollutant concentrations in German urban wastewater systems is available from recently completed monitoring projects. It contains up to 1000 concentration values for each of 79 substances in wastewater treatment plant (WWTP) effluents from 49 sites, and up to 157 values for each of 95 substances in combined sewer overflows (CSOs) from 12 sites. WWTP influents and stormwater outfalls were sampled to a lesser extent. All sampling methods were harmonised and aimed at collecting event or multi-day composite samples over periods of ≥1 year. Among the substances analysed were biocides and pesticides, polycyclic aromatic hydrocarbons, perfluorinated alkyl substances, metals, pharmaceuticals, benzotriazoles, phenols, acesulfame, di-(2-ethylhexyl)phthalate, and hexabromocyclododecanes. Occurrence, concentration ranges, and removal rates of selected WWTPs are presented. CSOs can be confirmed as an important pathway of metals and PAH to receiving waters when compared to WWTPs on the basis of annual per capita loads. The derived volume-weighted site mean concentrations are qualified to be used as representative input data for estimation of average substance emissions in large areas, e.g. on river basin scale, if no site-specific data are available. As such, they will contribute to the development of strategies to reduce substance emissions, taking into account not only WWTPs but also stormwater-related discharges.

The role of marshall bundle epicardial connections in atrial tachycardias after atrial fibrillation ablation

Funding Acknowledgements

Type of funding sources: None.

Background

Atrial tachycardias (ATs) are often seen in the context of AF ablation.

Objectives

We evaluated the role of the Marshall bundle (MB) network in left atrial (LA) ATs using high-density high-spatial resolution 3D mapping.

Methods

199 post-AF ablation LA tachycardias were mapped in 140 consecutive patients (112 (80%) males, mean age: 61.8 years); 133 (66.8%) were macro-reentrant and 66 (33.2%) were scar-related re-entry. MB-dependent perimitral AT (PMAT) was diagnosed where the difference between the post pacing interval and the tachycardia cycle length (PPI-TCL) was &lt;20ms in parts of the expected MB-dependent perimitral circuit (within the VOM, the ridge between the left pulmonary veins and LA appendage (LAA), the anterior LA and between 6- and 11-o’clock of the mitral annulus) and the PPI-TCL was &gt;20ms in areas bypassed by the VOM (the distal coronary sinus (CS), the posterior LA and the mitral isthmus). MB-related re-entry was diagnosed by PPI-TCL &lt;20ms at the left lateral ridge, posterior base of LAA, inferolateral LA or VOM ostium; and PPI-TCL &gt;20ms in the septal annulus. Typically, in MB-dependent localized re-entry, the earliest activation was found along the MB-LA endocardial connection or MB-CS epicardial connection. 

Results

The MB network was found to participate in 60 (30.2%) re-entrant ATs, 31 PMATs and 29 localized re-entries. High-frequency multiphasic fragmented electrograms with long duration were often recorded endocardially or epicardially at the MB-LA or MB-CS connections. The amplitude and duration of these signals were 0.5 ± 0.79 mV and 65 ± 40 ms for MB-PMATs and 0.26 ± 0.28mV and 122 ± 67 ms for MB-localized re-entries. Unipolar EGMs at the site of endocardial-epicardial breakthrough had a rS pattern in all MB-related ATs. Of 60 MB-related ATs, 49 (81.6%) terminated with RF ablation, 44 (73.3%) at the MB-LA junction and 5 (8.3%) at the MB-CS junction, while 9 (15%) terminated after 2.5-5 cc of alcohol infusion inside the vein of Marshall (VOM). Of the 31 MB-related macroreentrant ATs, 17 (54.8%) terminated at the MB-LA junction, 5 (16.1%) at the MB-CS junction and 7 (22.6%) with alcohol infusion inside the VOM. Two macroreentries (6.5%) using the MB did not terminate with RF energy either endocardially at the MB-LA junction or epicardially at the MB-CS junction, and we were unable to identify or cannulate the VOM for ethanol infusion. Of the 29 localized re-entrant ATs using the MB, 27 (93.1%) terminated at the MB-LA junction, none terminated at the MB-CS junction and 2 (6.9%) terminated after alcohol infusion. After a mean follow up of 12 months, only 4 patients (6.7%) had AT recurrence.

Conclusions

MB re-entrant ATs accounted for up to 29% of the left ATs after AF ablation. Ablation of the MB-LA or CS-MB connections or alcohol infusion inside the VOM is required to treat these arrhythmias. Abstract Figure.

Removal of Trace Organic Contaminants by Parallel Operation of Reverse Osmosis and Granular Activated Carbon for Drinking Water Treatment

In response to increasingly stringent restrictions for drinking water quality, a parallel operation of two common technologies, low-pressure reverse osmosis (LPRO) and activated carbon filtration (ACF), was investigated in a comprehensive five-month pilot study for the removal of 32 typical trace organic contaminants (TrOCs) from Rhine bank filtrates employing a semi- technical plant. TrOCs have been divided into three groups: polyfluorinated aliphatic compounds; pharmaceuticals, pesticides and metabolites; in addition to volatiles, nitrosamines and aminopolycarboxylic acids, which were also examined. The net pressure behavior, normalized salt passage and rejection of TrOCs by LPRO were investigated and compared with ACF operation. In addition, autopsies from the leading and last membrane modules were performed using adenosine triphosphate (ATP), total organic carbon (TOC), ICP-OES and SEM-EDX techniques. Generally, rather stable LPRO membrane performance with limited membrane fouling was observed. TrOCs with a molecular weight of ≥ 150 Da were completely retained by LPRO, while the rejection of di- and trichloro compounds improved as the filtration progressed. ACF also showed significant removal for most of the TrOCs, but without desalination. Accordingly, the ACF and LPRO can be operated in parallel such that the LPRO permeate and the ACF-treated bypass can be mixed to produce drinking water with adjustable hardness and significantly reduced TrOCs.

Long-term follow-up of patients with tetralogy of Fallot and implantable cardioverter defibrillator

Background

Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart disease, and sudden cardiac death represents an important mode of death in these patients. Data evaluating the implantable cardioverter defibrillator (ICD) in this patient population remain scarce.

Purpose

We aimed to describe long-term follow-up of patients with TOF and ICD through a large nationwide registry.

Methods

Nationwide Registry including all TOF patients with an ICD initiated in 2010. The primary outcome was the first appropriate ICD therapy. Secondary outcomes included ICD-related complications, heart transplantation, and death. Clinical events were centrally adjudicated by a blinded committee. Cox proportional hazard models were used to identify predictors of appropriate ICD therapies and ICD-related complications.

Results

A total of 165 patients (mean age 42.2±13.3 years, 70.1% males) were included from 40 centers, including 104 (63.0%) in secondary prevention. During a median (IQR) follow-up of 6.8 (2.5–11.4) years, 78 (47.3%) patients received at least one appropriate ICD therapy, giving an annual incidence of 10.5% (7.1% and 12.5% in primary and secondary prevention, respectively, p=0.03). Overall, 71 (43.0%) patients presented with at least one complication, including inappropriate ICD shocks in 42 (25.5%) patients and lead/generator dysfunction in 36 (21.8%) patients. Among 61 (37.0%) primary prevention patients, the annual rate of appropriate ICD therapies was 4.1%, 5.3%, 9.5%, and 13.3% in patients with respectively no, one, two, or ≥ three guideline-recommended risk factors. In our cohort, QRS fragmentation was the only independent predictor of appropriate ICD therapies (HR 4.34, 95% CI 1.42–13.23), and its integration in a model with current criteria increased the area under the curve from 0.61 to 0.72 (p=0.006). No patient with left ventricular ejection fraction (LVEF) ≤35% without at least one other risk factor had appropriate ICD therapy. Patients with congestive heart failure and/or reduced LVEF had a higher risk of non-sudden death or heart transplantation (HR=11.01, 95% CI: 2.96–40.95).

Conclusions

Our findings demonstrate high rates of appropriate therapies in TOF patients with an ICD, including in primary prevention. The considerable long-term burden of ICD-related complications, however, underlines the need for careful candidate selection. A combination of easy-to-use criteria might improve risk stratification beyond low LVEF.

Freedom from appropriate ICD therapy

Funding Acknowledgement

Type of funding source: None

Efficacy of deep sedation for patients with intractable electrical storm refractory to anti-arrhythmic drugs

Background

Sympathetic overactivity is implicated in the initiation and maintenance of electrical storm (ES). Deep sedation has empirically been considered as an efficient therapeutic option to blunt sympathetic tone and control ES.

Purpose

The aim of this multicenter study was to determine the efficacy of deep sedation in patients presenting intractable ES refractory to anti-arrhythmic drugs.

Methods

Patients requiring deep sedation for refractory ES from January 1st 2007 to July 31st 2018 were retrospectively included in 13 centers. The primary endpoint was the rate of acute response to sedation, defined as ES termination within 15 minutes after deep sedation.

Results

Among the 116 patients, 55 (47.4%) had ES termination within 15 minutes and were considered “acute responders” to deep sedation. Clinical signs of congestive heart failure before deep sedation (OR=3.31, 95% CI:1.001–10.97, p=0.049) was the only independent predictor of non-acute response. Twenty-one non-acute responders (34.4%) had an extracorporeal membrane oxygenation (ECMO) implanted. Non-acute responders had a significantly lower in-hospital survival (Log-rank, p=0.010). ECMO implantation did not influence survival in non-acute responders to sedation. Acute response to deep sedation was an independent protector of in-hospital mortality, decreasing by 73% the risk of death (OR 0.27; 95% CI:0.10–0.70, p=0.008).

Conclusion

To the best of our knowledge, this multicenter study is the first analysis of the efficacy of deep sedation in patients with intractable ES refractory to anti-arrhythmic drugs, and demonstrating the positive impact of “acute response” on in-hospital survival.

Funding Acknowledgement

Type of funding source: None

Joint Position Paper of the Working Group of Pacing and Electrophysiology of the French Society of Cardiology (SFC) and the Société française d'imagerie cardiaque et vasculaire diagnostique et interventionnelle (SFICV) on magnetic resonance imaging in patients with cardiac electronic implantable devices

Magnetic resonance imaging (MRI) has become the reference imaging for the management of a large number of diseases. The number of MR examinations increases every year, simultaneously with the number of patients receiving a cardiac electronic implantable device (CEID). A CEID was considered an absolute contraindication for MRI for years. The progressive replacement of conventional pacemakers and defibrillators by MR-conditional CEIDs and recent data on the safety of MRI in patients with "MR-nonconditional" CEIDs have progressively increased the demand for MRI in patients with a CEID. However, some risks are associated with MRI in CEID carriers, even with "MR-conditional" devices because these devices are not "MR-safe". A specific programing of the device in "MR-mode" and monitoring patients during MRI remain mandatory for all patients with a CEID. A standardized patient workflow based on an institutional protocol should be established in each institution performing such examinations. This joint position paper of the Working Group of Pacing and Electrophysiology of the French Society of Cardiology and the Société française d'imagerie cardiaque et vasculaire diagnostique et interventionnelle (SFICV) describes the effect and risks associated with MRI in CEID carriers. We propose recommendations for patient workflow and monitoring and CEID programming in MR-conditional, "MR-conditional nonguaranteed" and MR-nonconditional devices.

Multiresidue Determination of Pesticides in Drinking and Related Waters by Solid-Phase Extraction and Liquid Chromatography with Ultraviolet Detection: Interlaboratory Study

As part of a project funded by the European Commission (EC) for the development and evaluation of multiresidue methods for analysis of drinking and related waters, 17 European laboratories evaluated a method using styrene–divinylbenzene copolymer solid-phase extraction followed by liquid chromatography with diode array detection. The main aim of the study was to evaluate whether the method meets the requirements of EC Drinking Water Directive 98/83 in terms of accuracy, precision, and detection limit for 21 pesticides according to the following requirements: limit of detection, ≤0.025 μg/L; accuracy expressed as recovery, between 75 and 125%; and precision expressed as repeatability relative standard deviation of the method, &lt;12.5%, and as reproducibility relative standard deviation of the method, &lt;25%. Analyses for unknown concentrations were performed with commercial bottled and tap waters. All laboratories were able to achieve detection limits of 0.01 μg/L for all pesticides except pirimicarb (0.02 μg/L). The criteria for repeatability were met for all compounds. Terbutryn in bottled water and carbendazim in tap water did not meet the criteria for reproducibility. In terms of accuracy, the method met the requirements for all pesticides in both matrixes, except for metamitron. However, several compounds (linuron, terbutryn, propazine, metobromuron, and isoproturon) showed recoveries slightly below 75%.

Multiresidue Determination of Pesticides in Drinking and Related Waters by Gas Chromatography/Mass Spectrometry after Solid-Phase Extraction: Interlaboratory Study

As part of a project funded by the European Commission (EC) for the development and evaluation of multiresidue methods for analysis of drinking and related waters, 15 European laboratories evaluated a method using styrene–divinylbenzene copolymer solid-phase extraction followed by gas chromatography/mass spectrometry. The main aim of the study was to evaluate whether the method meets the requirements of EC Directive 98/83 in terms of accuracy, precision, and detection limit for 22 pesticides according to the following requirements: limit of detection, ≤0.025 μg/L; accuracy, expressed as recovery between 75 and 125%; and precision, expressed as repeatability relative standard deviation of the method of &lt;12.5% and as reproducibility relative standard deviation of the method of &lt;25%. Analyses for unknown concentrations were performed with fortified commercial bottled and tap waters. All laboratories were able to achieve detection limits of 0.01 μg/L for all pesticides except dimethoate and desisopropylatrazine (0.02 μg/L). The criteria for repeatability were met for all compounds except trifluralin, dimethoate, and lindane in bottled water and chlorpyrifos, dimethoate, and lindane in tap water. The criteria for reproducibility were met for all compounds except trifluralin, dimethoate, and lindane in bottled water and pendimethalin, chlorpyrifos, dimethoate, terbutryn, and lindane in tap water. In terms of accuracy, the method meets the requirements for all pesticides in both matrixes, except for lindane in bottled water and lindane and chlorpyrifos in tap water.

P5694Outcomes of patients with arrhythmogenic right ventricular cardiomyopathy after ventricular tachycardia ablation without an implantable cardioverter-defibrillator: a multicenter international study

Background

In arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D), implantable cardioverter-defibrillators (ICD) after an episode of sustained monomorphic ventricular tachycardia (MVT) are currently recommended in most situations. However, radiofrequency catheter ablation (RCA) is effective in reducing recurrent VT and whether MVT is a surrogate of sudden cardiac death is debated when other risk factors are lacking.

Purpose

To report the outcomes of patients with ARVC/D who underwent RCA of well-tolerated MVT without a back-up ICD.

Methods

Patients with a definite ARVC/D diagnosis according to the 2010 Task Force revised criteria who underwent RCA of well-tolerated MVT at 9 tertiary centers across 5 countries, without an ICD prior to RCA and in the 3 following months were retrospectively included. Patients presenting with syncope or electrical storm, and patients with left ventricular ejection fraction <50% were excluded. Similar patients implanted with an ICD prior or without RCA in the same period served as controls.

Results

Sixty-five patients [median age 46.1 years, range (19.5–73.8), 75% males] underwent RCA of MVT between 2003 and 2016. Familial history of ARVC/D was found in 11% of patients. Epsilon-waves were present in 19% and T-waves inversion beyond V2 in 43%. A right ventricular (RV) ejection fraction ≤40% or fractional area change ≤33% was found in 14 (25%) patients. Median left ventricular ejection fraction was 61% (50–70). Clinical presentation was palpitations in 81% of patients and near-syncope in 14%. Prior to RCA, patients were on beta-blockers alone in 18%, class I drugs in 37% and amiodarone in 9%, while 15% of patients were free any antiarrhythmic medication. Only 1 patient (2%) had >1 clinical VT morphology. Median VT rate was 180 (110–270). An epicardial approach was used in 31% patients. The clinical VT was inducible in 84% of patients. The median number of targeted RV site was 1 (1–3) (RV outflow tract in 72%). Full acute success defined inability to induce any VT was achieved in 72% of patients. During a median follow-up time of 49 month (1.4–162), there was no death or aborted cardiac arrest. Survival without VT recurrence was estimated at 82%, 71% and 60%, 12-, 36- and 60-months after RCA. No VT recurrence was observed among patient who had undergone an epicardial ablation. Among patients with VT recurrence, 6 (35%) did not receive an ICD, and 14 (70%) underwent redo RCA. An ICD was implanted in 10 patients, including 5 for VT recurrence. Fifty-eight patients constituted the control group, and 64% had appropriate ICD interventions during follow-up.

Conclusions

Despite a significant rate of VT recurrence, selected patients with ARVC/D who underwent RCA for stable MVT without an ICD did not experience any arrhythmic death. Further prospective studies are mandatory to precise the respective places of ICD and RCA in the management of ARVC/D patients with well-tolerated MVT.

Acknowledgement/Funding

None

Determination of monochloramine dissipation kinetics in various surface water qualities under relevant environmental conditions - Consequences regarding environmental risk assessment

A total 190 experiments were performed to study the dissipation kinetics of monochloramine (NH₂Cl, CAS no 10599-90-3) in surface water samples from six rivers (Loire, Rhône, Meuse, Garonne, Seine and Moselle) and an artificial reservoir (Mirgenbach), all located in France. Experiments were conducted in an open reactor, under relevant controlled environmental conditions. The impact of various parameters such as initial NH₂Cl concentration, temperature, pH, presence of sediments, sampling site and collection period was investigated. It was found that NH₂Cl dissipated rapidly without any lag phase, and that decay follows an apparent first-order kinetics (r² > 0.99). Presence of sediment greatly accelerated decay. Half-lives were generally <1 h in river water in presence of natural sediment, but of several hours without sediment. The impact of pH was low for the normal river water pH range. However, increase in temperature significantly accelerated decay. The combination of high initial NH₂Cl concentrations and elevated temperatures generally gives half-lives similar to those obtained at lower temperatures and lower concentrations. Short half-lives (0.06 to 1.50 h) were found in all the surface waters examined, regardless of geographic location of sampling site or collection period, indicating no temporal or site-specific effects on NH₂Cl dissipation. Decay was slightly faster at lower initial concentrations, which supports extrapolation of half-lives measured in this study to a wide range of environmental concentrations. It can thus be assumed that NH₂Cl degradation in river and reservoir waters is mainly determined by presence of sediments and temperature.

P5027Prognosis and evaluation of the risk markers of arrhythmia in a large population of Brugada syndrome patients

Introduction

Brugada syndrome (BrS) is an inherited arrhythmia syndrome with an increased risk of sudden cardiac death (SCD) despite a structurally normal heart. Many parameters have been suggested to be associated with the risk of ventricular arrhythmias, but only previous symptoms and spontaneous ECG pattern have been consistently associated with the risk of ventricular arrhythmia occurrence.

Objective

The aim of this study was to evaluate the association of these parameters with arrhythmic events in the largest cohort of BrS patients ever described.

Methods

Consecutive patients affected with BrS were recruited in a multicentric prospective registry in France (15 centers) between 1994 and 2016. Data were prospectively collected with an average follow-up of 6.5±4.7 years. ECGs were reviewed by 2 physicians blinded to clinical status.

Results

In this study, we enrolled a total of 1613 patients (mean age 45±15 years; 1119 males, 69%). At baseline, 462 patients (29%) were symptomatic (51 (3%) aborted SCD, 257 (16%) syncope). A spontaneous type 1 ECG pattern was present in 505 patients (31%). Implantable cardiac defibrillator was implanted in 477 patients (30%).

During the follow-up, 91 patients (6%) underwent arrhythmic events (16 SCD (10%), 48 appropriate ICD therapy (3%) and 27 ventricular arrhythmias (2%). Thirty-six patients (2%) died of non-arrhythmic causes. Mean age at the first event was 44±15 years.

In our cohort, event predictors were SCD (HR: 18.3; 95% CI: 11.2–29.8; p<0.0001), syncope (HR: 2.9; 95% CI: 1.8–4.9; p<0.0001), age >60 years (HR: 0.11; 95% CI: 0.032–0.377; p=0,0004), gender (HR: 2.96; 95% CI: 1.6–5.4; p=0.0005), spontaneous type 1 (HR: 2.14; 95% CI: 1.42–3.23; p=0.0003), type 1 ST elevation in peripheral ECG lead (HR: 3.6; 95% CI: 1.9–7.1; p=0,0001), fragmented QRS (HR: 3.37; 95% CI: 1.37–8.32; p=0,008), AvR sign (HR: 2.2; 95% CI: 1.4–3.8; p=0,0007), QRS >120ms in D2 lead (HR: 2.2; 95% CI: 1.4–3.6; p=0,001) and QRS >90ms in V6 (HR: 2.1; 95% CI: 1.3–3.3; p=0,001). All the others parameters including early repolarization pattern (ERP) and EPS were not predictor of events.

Conclusion

In the largest cohort of BrS patients ever described, we confirmed that symptoms, age, gender, spontaneous type 1, type 1 ST elevation in peripheral ECG lead, fragmented QRS, AvR sign, QRS >120ms in D2 and QRS >90ms in V6 are associated with arrhythmic events whereas ERP and EPS were not.

P6585Number of ECG leads and prognosis of spontaneous type 1 Brugada syndrome

Introduction

Brugada syndrome (BrS) is an inherited arrhythmia syndrome with an increased risk of sudden cardiac death (SCD). The recent single lead-based diagnosis of Brugada syndrome recommended criterion may lead to overdiagnosis of Brugada syndrome and overestimation of the risk of SCD.

Objective

We aim to investigate the value of a single lead diagnosis in spontaneous type 1 ECG Brugada patient and to investigate the association between the number of ECG leads with a spontaneous type 1 ST elevation and the arrhythmic risk.

Methods

Consecutive patients affected with BrS were recruited in a multicentric prospective registry in France (15 centers) between 1994 and 2016. A total of 1613 patients affected by the Brugada syndrome were enrolled. For this specific study, only patient with a spontaneous type 1 BrS were enrolled (n=505). Data were prospectively collected with an average follow-up of 6.5±4.7 years. ECGs were reviewed by 2 physicians blinded to clinical status. Type 1 ST elevation was defined by ≥2 mm J-point elevation with coved ST segment and negative T wave.

Results

A total of 505 patients with a spontaneous type 1 BrS (mean age 46±15 years, 398 males, 79%) were enrolled. 117 patients (23%) were symptomatic at baseline (32 (6%) aborted SCD, 85 (17%) syncope). Implantable cardiac defibrillator (ICD) was implanted in 191 patients (38%).

Brugada ECG pattern was found in 1 lead in 250 patients (50%, group 1), in 2 leads in 227 patients (45%, group 2) and in 3 leads in 28 patients (5%, group 3). Groups were comparable in term of clinical presentation except for group 3 who presented more frequently an early repolarization pattern (n=19 (8%) in group 1, n=15 in group 2 (6%) and n=7 (25%) in group 3, p=0.02) and more frequently QRS fragmentation (n=6 (2%) in group 1, n=3 in group 2 (1%) and n=3 (11%) in group 3, p=0.03).

During follow-up, 46 (9%) patients presented an arrhythmic event: 22 (9%) in group 1 (4 SCD, 14 appropriate ICD therapy, 4 ventricular arrhythmias), 22 (10%) in group 2 (6 SCD, 11 appropriate ICD therapy, 5 ventricular arrhythmias) and 2 (7%) in group 3 (1 SCD, 1 appropriate ICD therapy). Patients with type 1 BrS pattern in 2 or 3 ECG leads had not a significantly higher rate of arrhythmic events than patients with type 1 BrS pattern in only 1 ECG lead (HR: 1.1; 95% CI: 0.6–1.9 for group 2 and HR: 0.7; 95% CI: 0.2–3 for group 2; p=0,087).

Conclusion

In the largest cohort of BrS patients ever described, the prognosis of Brugada syndrome with a spontaneous ECG pattern does not appear to be affected by the number of leads required for diagnostic.

P6581Association of neuro-psycho-behavioral troubles to catecholaminergic polymorphic ventricular tachycardia: a more severe arrhythmic phenotype?

Methods

This is a retrospective observational study based on case analysis from the INTEGRALIS database of the referral center for inherited cardiac arrythmias in Nantes. Epidemiological and clinical-biological features of the population have been studied. Patients with Presence or Absence of NPBT were compared. Results:From 8306 pts in the whole database, 533 presented with VT and 71 pts were diagnosed with CPVT and genotyped. Symptom onset occurred at a medium age of 17.1±13.5 years. Median LVEF was 65% (IQR 9,8%) and median corrected QT interval (QTc) was 399 ms (IQR 27 ms). 77.5% of pts had fainting and/or syncopes, and there were 28.2% patients with a history of cardiac arrest. Time to diagnosis was below1 year for 44.2% of symptomatic pts. Symptoms occurred during exertion for 42.3% of pts including swimming. The prevalence of NPBT was 23,9%. 74% of NPBT were convulsive seizures, 21% psycho-behavioral troubles and 5% epilepsy proved by EEG. Median age of symptom onset was younger in the group “NPBT” (12.2±4 yo vs 19.2±15.5 yo). The rate of patients with symptoms during exertion was higher in the group “NPBT” (29.4 vs 7.4% P=0.031). A mutation in the gene of Ryanodine receptor-2 was found in 64.8% of pts.

Comparisons patients w/wo NPBT NPBT (N=17) Without NPBT (N=54) Familial history of Sudden death 7/17 (41.2%) 24/54 (44.4%) NS Familial history of CPVT 5/17 (29.4%) 29/54 (53.7%) NS Medium age of symptom onset (yo) 12.1±4 19.2±15.5 P=0.021 Time to diagnosis <1 year 4/17 (23.5%) 16/54 (27.8%) NS Malaises and/or syncopes 17/17 (100%) 38/54 (70.4%) P=0.035 Cardiac arrest 9/17 (52.9%) 11/54 (20.4%) P=0.025 ICD Implantation 6/17 (35.3%) 12/54 (22.2%) NS Supraventricular arrhythmias 3/17 (17.7%) 6/54 (11.1%) NS Antiepileptic treatment 5/17 (29.4%) 2/54 (3.7%) P=0.009

Conclusion

NPBT appears to be associated to a younger age of symptom onset and a higher rate of serious cardiac events particularly during swimming. This study will serve as preliminary data for further clinical and experimental protocols.

5201Intra-cardiac thrombus in patients undergoing ventricular tachycardia ablation. a computed tomographic scan study

Background

Embolic event is one of the complications of VT ablation. This may be due to the presence of intra-cardiac thrombus before ablation. However, there is no clear consensus on how to rule out thrombus before the procedure.

Objective

We sought to examine the prevalence and risk factors of intra-cardiac thrombus with cardiac computed tomographic (CT) scan in patients undergoing scar-related VT ablation.

Methods

In absence of contra-indication, all patients undergoing scar-related VT ablation at our institution underwent contrast-enhanced cardiac CT within one week before ablation. 324 consecutive patients (292 male, 59±16 yo) have been included in this study. The etiology was ischemic cardiomyopathy (CMP) (n=191), arrhythmogenic right ventricular CMP (ARVC) (n=37), congenital CMP (n=11) or other CMP (n=85). LVEF was <40% in 154 patients (48%).

Results

Intra-cardiac thrombus was diagnosed in 29 (9%) patients: in the left atrium (n=8), in the right atrium (n=1), in the left ventricle (n=15), in the right ventricle (n=3), in right and left atrium (n=1), and in left atrium and right ventricle (n=1). Moreover in 2, a bilateral pulmonary embolism was identified. The population with thrombus was older (65±12 vs 58±16 years, p=0,005), with more permanent atrial fibrillation (AF) (28% vs 8%; p=0.005). Patients with left ventricular (LV) aneurysm were at higher risk of thrombus 50% vs 3% (p<0.001). The average CHADSVASC score was similar for both groups (2,5 vs 2,1; p=0.179). After matching for age and sex, only ischemic CMP and LV aneurysm were risk factors for thrombus. Because of arrhythmic storm, ablation was performed by epicardial approach only, in 5 patients with intra-ventricular thrombus and by retroaortic approach only, in 2 patients with LAA thrombus. No embolic event occurred during these procedures.

Conclusion

CT scans help eliminating intra-cardiac thrombus before VT ablation procedure. A high proportion of thrombus (9%) was identified. Whereas LV thrombus should systematically be ruled out before scar related VT ablation, in patients with AF, a LAA thrombus should also be eliminated as well as RV thrombus in patients with ARVC.

Acknowledgement/Funding

ANR-10-IAHU-04

P6587The experience of a French specialized inherited arrhythmia center in the management of long QT syndrome patients

Introduction

Congenital long QT syndrome (LQTS) is a hereditary disease characterized by prolonged QTc interval and risk of ventricular tachyarrhythmias, which may lead to syncope, cardiac arrest, or sudden death in young people.

Objective

The aim of this study is to report the experience of the French referral center of inherited arrhythmia of the University Hospital of Nantes.

Methods

Consecutive patients affected with lonq QT syndrome were recruited in a multicentric prospective registry in France (15 centers) between 1997 and 2018. Clinical data and 12-lead ECG were collected. Genetic screening was performed using dHPLC-DNA sequencing, HRM or targeted sequencing for at least KCNQ1, KCNH2 and SCN5A.

Results

In this study, we enrolled a total of 741 patients affected by LQTS according to the Schwartz score (447 (60%) females, 404 (55%) index cases). Mean age at diagnosis was 33±21 years. In this cohort, 343 patients (46%) were symptomatic: 66 patients experienced resuscitated sudden cardiac death (SCD, 9%), 211 (28%) syncope and 66 (9%) ventricular arrhythmias. One hundred and two patients (14%) had history of familial SCD. At baseline, heart rate was 69±19 bpm, PR 149±39 mm, QRS 86±16 mm and QTc 479±62 mm.

Three hundred and eighty-six patients (52%) were treated with beta-blockers and 88 patients (12%) were implanted with an ICD.

Genetic screening was performed in 668 (90%) patients. Genetic screening for the 3 major genes of LQTS was positive for 411 patients (62%): 165 variants (25%) in KCNQ1, 178 variants (27%) in KCNH2, 68 variants (10%) in SCN5A. Moreover, we found variants in minor genes of LQTS for 22 patients (3%).

During a mean follow-up of 6.2±5.2 years, 64 patients (9%) underwent arrhythmic events (7 SCD (1%), 8 appropriate ICD therapy (1%) and 49 ventricular arrhythmias (7%). The rate of arrhythmic event was 1.39%/y. Mean age at the first event was 41.7±21.5 years. Sixteen patients (2%) died of non-arrhythmic causes.

Conclusion

Care in a specialized inherited arrhythmia center is associated with a low incidence of arrhythmic event (1.39%/y) in patients affected with LQTS.

P2279First clinical evaluation of subcutaneous implantable cardiac defibrillator in Brugada patients

Background

Brugada syndrome (BrS) is an inherited arrhythmia syndrome with an increased risk of SCD. While Subcutaneous ICD (S-ICD) is a seductive approach to treat these patients, questions raised on the risk of inappropriate shock in this specific population.

Objective

The aim of this study was to evaluate the safety and the effectiveness of the S-ICD in BrS patients.

Methods

We prospectively enrolled 112 BrS patients implanted with S-ICD in 17 European centers. During the screening at least 2 vectors must be suitable but it was not necessary to check for the suitability of the ECG during sodium channel blocker or exercise test. S-ICD indications follow the current guidelines.

Results

Mean age of patients was 45±13 years, with 95 (85%) males. Implantation was performed in 91 (83%) patients for primary prevention and in 18 (16%) patients for secondary prevention. There is an indication of ICD replacement for 16 patients (14%): 13 lead defect (81%), 1 infection (6%) and 2 ICD end of life (13%). In this cohort, 57 patients (51%) had spontaneous type I BrS, 60 patients (55%) were symptomatic: 10 resuscitated SCD (17%) and 48 (83%) syncope.

Implantation was performed under general anesthesia in 79 patients (71%). The mean operation time was 56±19 min. The lead was placed at the left side of the sternum in 102 patients (92%) and at the right side in 9 (8%). Sensing configuration was the primary vector for 46 patients (41%), secondary vector for 57 (51%) and alternative vector for 9 (8%). No complications occurred during implantation.

During a mean follow-up of 15.6 months (0–39 months), 6 patients (5%) had at least one appropriate shock (n=9). The rate of appropriate shock was 4.5%/y. All the VF episodes were successfully treated with the first shock. One patient had VF ablation for recurrent VF. Among the 6 patients who received an appropriate shock, 3 (50%) were implanted for secondary prevention and 3 (50%) were implanted for primary prevention including 2 patients with a history of syncope and one asymptomatic patient.

Twelve patients (11%) had at least one inappropriate shock (n=22) including 2 patients with respectively 8 and 4 inappropriate shocks due to T-wave oversensing. With the SMART pass system the first patient had no more inappropriate shock for now 2 years. The rate of inappropriate shock was 9%/y. One patient died of myocardial infarction.

Five patients (4%) were hospitalized for complications (4 pocket or scar infections and 1 electrode failure).

Conclusion

Our initial experience showed that S-ICD is efficient to treat VF episode in BrS patients. In this population, the rate of inappropriate shock was 9%/y. In view of these results, S-ICD implantation seems to be efficient to protect BrS patients against SCD.

Acknowledgement/Funding

Investigator-Sponsored Research program, Boston Scientific

5164New risk prediction score for life-threatening ventricular tachyarrhythmias in laminopathies

Background

An accurate estimation of the risk of life-threatening (LT) ventricular tachyarrhythmia (VTA) in patients with LMNA mutations is crucial to select candidates for implantable cardioverter defibrillator (ICD) implantation.

Methods

We included 839 adult patients with LMNA mutations, including 660 from a French nationwide registry in the development sample, and 179 from other countries, referred to 5 tertiary centers for cardiomyopathies, in the validation sample. LTVTA was defined as a) sudden cardiac death or b) ICD-treated or hemodynamically unstable VTA. The prognostic model was derived using Fine-Gray's regression model. The net reclassification was compared with current clinical practice guidelines. The results are presented as means (standard deviation) or medians [interquartile range].

Results

We included 444 patients 40.6 (14.1) years of age in the derivation sample and 145 patients 38.2 (15.0) years in the validation sample, of whom 86 (19.3%) and 34 (23.4%) suffered LTVTA over 3.6 [1.0–7.2] and 5.1 [2.0–9.3] years of follow-up, respectively. Predictors of LTVTA in the derivation sample were: male sex, non-missense LMNA mutation, 1st degree and higher atrioventricular block, non-sustained ventricular tachycardia, and left ventricular ejection fraction. In the derivation sample, C-index (95% CI) of the model was 0.776 (0.711–0.842). In the external validation sample, the C-index was 0.800 (0.642–0.959) and calibration slope 1.082 (95% CI, 0.643–1.522). A 5-year estimated risk threshold ≥7% predicted 96.2% of LTVTA and net reclassified 28.8% of patients with LTVTA compared with the guidelines-based approach.

Conclusions

Compared to the current standard of care, this risk prediction model for LTVTA in laminopathies facilitated significantly the choice of ICD candidates.

Acknowledgement/Funding

AFM Téléthon

P1899Heparin and low-molecular-weight heparin switch associated with an increase in bleeding complications in patients on apixaban undergoing catheter ablation: The AMPER ABLATION study

Background

The aim of this study was to identify the factors associated with bleeding complications in patients taking apixaban and undergoing a catheter ablation in everyday clinical practice.

Methods

AMPER ABLATION is a multicenter, observational, prospective study of patients with non valvular atrial fibrillation (AF) undergoing a catheter ablation. Eligible patients had been taking apixaban (2.5 or 5 mg twice daily) for ≥3 weeks before the procedure, and were followed for 30 days afterwards.

Results

A total of 595 patients (65 [interquartile range 59, 72] years, 67% male, mean CHA2DS2-VASc score 1.85±1.37) were enrolled at 25 academic/nonacademic centers in France; 524 patients (88%) were receiving apixaban 10 mg/day and 71 (12%) 5 mg/day. 323 patients (54%) underwent an AF ablation, and 272 (46%) an atrial flutter (AFL) ablation. The most prevalent concomitant disorders were hypertension (51% of patients), diabetes (15%) and vascular disease (10%). Mean creatinine concentration was 1.06±0.28 mg/dL, median weight was 83±18 kg and mean creatinine clearance (Cockcroft-Gault) was 82±34 mL/min. The management of apixaban in the periprocedural period was left to the investigator's preference. Overall, 264 patients were switched to unfractionated heparin or enoxaparin (238 for AF ablations and 26 for AFL ablations). The median duration of switch was 29 hours. Complications were reported at 30 days, and included 12 bleeding events (1 tamponade needing drainage, 1 pericardial effusion without drainage, 7 International Society on Thrombosis and Haemostasis [ISTH] non major bleedings for AF ablations and 1 pericardial effusion without drainage, and 2 ISTH non major bleedings for AFL ablations) and 1 embolic event (non disabling stroke for an AF ablation). Comparing patients with and without a bleeding event revealed a higher rate of heparin or low-molecular-weight heparin (LMWH) switching in patients with a bleeding event (60% vs 35%; p=0.02). A switch to heparin or LMWH was the only factor associated with an increase rate of bleeding (odds ratio 2.5; [CI 95%; 1.1, 7.1]; p=0.01).

Conclusion

Heparin or LMWH switch in the periprocedural AF and AFL-ablation period is associated with an increased rate of bleeding complications at 30 days.

Acknowledgement/Funding

Financial support from BMS

Prospective environmental risk assessment of mixtures in wastewater treatment plant effluents - Theoretical considerations and experimental verification

The aquatic environment is continually exposed to a complex mixture of chemicals, whereby effluents of wastewater treatment plants (WWTPs) are one key source. The aim of the present study was to investigate whether environmental risk assessments (ERAs) addressing individual substances are sufficiently protective for such coincidental mixtures. Based on a literature review of chemicals reported to occur in municipal WWTP effluents and mode-of-action considerations, four different types of mixtures were composed containing human pharmaceuticals, pesticides, and chemicals regulated under REACH. The experimentally determined chronic aquatic toxicity of these mixtures towards primary producers and the invertebrate Daphnia magna could be adequately predicted by the concept of concentration addition, with up to 5-fold overestimation and less than 3-fold underestimation of mixture toxicity. Effluents of a municipal WWTP had no impact on the predictability of mixture toxicity and showed no adverse effects on the test organisms. Predictive ERAs for the individual mixture components based on here derived predicted no effect concentrations (PNECs) and median measured concentrations in WWTP effluents (MC_eff) indicated no unacceptable risk for any of the individual chemicals, while MC_eff/PNEC summation indicated a possible risk for multi-component mixtures. However, a refined mixture assessment based on the sum of toxic units at species level indicated no unacceptable risks, and allowed for a safety margin of more than factor 10, not taking into account any dilution of WWTP effluents by surface waters. Individual substances, namely climbazole, fenofibric acid and fluoxetine, were dominating the risks of the investigated mixtures, while added risk due to the mixture was found to be low with the risk quotient being increased by less than factor 2. Yet, uncertainty remains regarding chronic mixture toxicity in fish, which was not included in the present study. The number and identity of substances composing environmental mixtures such as WWTP effluents is typically unknown. Therefore, a mixture assessment factor is discussed as an option for a prospective ERA of mixtures of unknown composition.

Is there synergistic interaction between fungicides inhibiting different enzymes in the ergosterol biosynthesis pathway in toxicity tests with the green alga Raphidocelis subcapitata?

Products used for plant protection or as biocides often contain more than one active substance together with numerous formulation additives. The environmental risk assessment for such commercial mixtures applies as default the concept of concentration addition. There is remaining regulatory concern, however, that underestimation of risks can occur if components in the mixture interact synergistically, i.e., elicit effects greater than those predicted by concentration addition. While cases of true synergism appear to be rare, the combination of substances targeting different steps in the same biosynthesis pathway was pointed out as one potential case of synergistic interaction although mechanistic explanations are lacking. The present study aimed to verify this hypothesis using the green alga Raphidocelis subcapitata as the regulatory standard test organism for which such synergism had been indicated earlier. Algal growth inhibition tests were conducted with mixtures of ergosterol biosynthesis inhibitors (tebuconazole, fenpropidin, and fenpropimorph). The fungicides were first tested individually to derive reliable data for a mixture toxicity prediction. The here determined toxicity estimates for two of the fungicides were considerably lower than the endpoints in the regulatory dossiers, which had been used for earlier mixture toxicity predictions. Experimentally observed toxicity estimates for the mixtures deviated <2.6-fold from the predicted values. Hence, the hypothesis of synergistic interaction between fungicides targeting different enzymes in the ergosterol biosynthesis was clearly not confirmed for the green alga R. subcapitata. Overall, the present study demonstrates the importance of reliable and correct input data for mixture toxicity predictions in order to avoid erroneous conclusions on non-additive (synergistic) interactions.

Environmental risk assessment of biocidal products: identification of relevant components and reliability of a component-based mixture assessment

BACKGROUND

Biocidal products are mixtures of one or more active substances (a.s.) and a broad range of formulation additives. There is regulatory guidance currently under development that will specify how the combined effects of the a.s. and any relevant formulation additives shall be considered in the environmental risk assessment of biocidal products. The default option is a component-based approach (CBA) by which the toxicity of the product is predicted from the toxicity of 'relevant' components using concentration addition. Hence, unequivocal and practicable criteria are required for identifying the 'relevant' components to ensure protectiveness of the CBA, while avoiding unnecessary workload resulting from including by default components that do not significantly contribute to the product toxicity. The present study evaluated a set of different criteria for identifying 'relevant' components using confidential information on the composition of 21 wood preservative products. Theoretical approaches were complemented by experimentally testing the aquatic toxicity of seven selected products.

RESULTS

For three of the seven tested products, the toxicity was underestimated for the most sensitive endpoint (green algae) by more than factor 2 if only the a.s. were considered in the CBA. This illustrated the necessity of including at least some additives along with the a.s. Considering additives that were deemed 'relevant' by the tentatively established criteria reduced the underestimation of toxicity for two of the three products. A lack of data for one specific additive was identified as the most likely reason for the remaining toxicity underestimation of the third product. In three other products, toxicity was overestimated by more than factor 2, while prediction and observation fitted well for the seventh product. Considering all additives in the prediction increased only the degree of overestimation.

CONCLUSIONS

Supported by theoretical calculations and experimental verifications, the present study developed criteria for the identification of CBA-relevant components in a biocidal product. These criteria are based on existing criteria stated in the regulation for classification, labelling and packaging of substances. The CBA was found sufficiently protective and reliable for the tested products when applying the here recommended criteria. The lack of available aquatic toxicity data for some of the identified relevant components was the main reason for underestimation of product toxicity.