How to better identify patients at high risk of inappropriate shocks before S-ICD implantation: Results from a multicenter experience

Funding Acknowledgements

Type of funding sources: None.

Introduction

Despite the recent improvements, inappropriate shocks (IAS) in patients implanted with subcutaneous implantable cardioverter-defibrillator (S-ICD) remain a challenge in "real-life" practice. The purpose of this study was to assess the preoperative predictive factors of IAS with the latest generation of S-ICD, with a particular focus on data obtained during the screening procedure.

Methods

Between January 2017 and March 2020, 300 patients implanted with Generation 3 S-ICD system for primary and secondary prevention were included in this multicentric study. Follow-up (FU) of at least 6 months and preoperative screening procedure data were mandatory for all patients.

Results

After a mean follow-up of 22.8 (±11.4) months, appropriate therapies occurred in 12.3% patients; while 26 patients (8.7%) experienced inappropriate therapies (incidence 4.9 per 100 patient-years). The total number of inappropriate shock episodes was 48; 9 patients experienced multiple episodes. Causes of IAS were: supraventricular arrhythmias (34.6%), cardiac (30.7%) and extra-cardiac noise oversensing (38.4%). In univariate analysis, availability of all 3 sensing vectors during preoperative screening significantly reduced inappropriate therapies occurrence (hazard ratio [HR], 0.32; 95% confidence interval [CI], 0.12-0.89, P=0.028). Clinical preoperative S-ICD inappropriate shocks predictors were: history of Supraventricular Tachycardia (SVT)(HR, 4.42; 95% CI, 1.45-13.47; P=0.009); overweight (BMI>25: HR, 1.93; 95% CI, 0.83-0.4.48; P=0.13); QRS duration (HR, 1.01; 95% CI, 0.1-1.03; P=0.14) and lower QRS/T wave ratio in lead I (for a threshold < 3: HR, 4.44; 95% CI, 1.88-10.48; P=0.001). By multivariate analysis, independent factors associated with IAS were: the availability of less than 3 sensing vectors during preoperative screening (p<0.05), a low QRS/T wave ratio in lead I (for a threshold <3; p<0.001), history of SVT (p<0.001) and overweight (BMI> 25; p<0.05).

Conclusion

Automatic preoperative screening data is of high interest as a predictor of IAS with a quantitative value. ECG specificities in association with other clinical factors should be taken into consideration to identify patients at high risk for IAS.

Success and complication rate of Tightrail mechanical percutaneous lead extraction: a multicenter French study

Background

Our objective was to assess Philips TightRail™ rotating dilator sheath efficacy and safety for extraction of endocardial leads. No large scale multicenter data is available on this mechanical lead extraction device, now commonly used in France.

Methods and results

We conducted a retrospective, multicenter (from 4 French university hospitals) study. These centers that only perform mechanical lead extraction using this device were selected on the basis of the annual volume of procedures (>10 leads/year). All patients from January 2015 to January 2020 who underwent at least one extraction of an endocardial lead with using TightRail™ were included. All of the extracted leads were >12 months old and indications for extraction were based on ESC guidelines.

Overall, 395 leads were extracted using TightRail™ in 203 patients (mean age 70 years, 75% male sex).

Indications for lead removal included cardiac device infection in 172 (85%) cases, lead malfunction in the 25 (12%) cases, vein thrombosis in 3 (1.5%) cases and 3 for other indications (1,5%). The extracted devices were pacemaker in 134 (66%) cases, implantable cardioverter-defibrillator (ICD) in 69 (44%) cases. The mean time from implantation was 124 months. Complete procedural success with TightRail™ system alone was achieved in 180 (89.1%) patients (352 leads) and overall clinical success was 93% (367 leads). Fifteen right sided leads were completely removed with the help of femoral snare. Ten (5%) patients had at least one major perioperative complication: 3 cardiac tamponades, 1 haemothorax, 1 stroke, 5 vascular breaches requiring surgical intervention. No in-hospital death was observed.

Conclusion

Our large scale retrospective study in 4 high-volume mechanical lead extraction centers shows that TightRail™ is highly effective for chronically implanted lead extraction. The safety profile appears similar to the rate recently described with power sheaths.

Funding Acknowledgement

Type of funding source: None

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.

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

Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study

BACKGROUND

Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery.

METHODS

This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy.

RESULTS

Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51-19.97) than planned admissions (OR: 2.32, 95% CI: 1.43-3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8-51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI.

CONCLUSIONS

After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.

Determination of association constants of beta-cyclodextrin and beta-cyclodextrin-bearing polymers with drugs by high-performance liquid chromatography

A high-performance liquid chromatographic (HPLC) support was prepared, based on silica beads coated with a beta-cyclodextrin-containing polymer, which allows the elution of solutes in order of their affinity for beta-cyclodextrin. Binding constants were determined from the retention data for drugs eluted with pure buffer on the new support and good agreement was observed with results obtained by the Hummel and Dreyer method, previously used in HPLC studies of drug-protein interactions.