Mitral Annular Disjunction in Idiopathic Ventricular Fibrillation Patients: Just a Bystander or a Potential Cause?

AIMS

Previously, we demonstrated that inferolateral mitral annular disjunction (MAD) is more prevalent in patients with idiopathic ventricular fibrillation (IVF) than in healthy controls. In the present study, we advanced the insights into the prevalence and ventricular arrhythmogenicity by inferolateral MAD in an even larger IVF cohort.

METHODS AND RESULTS

This retrospective multicentre study included 185 IVF patients (median age 39 [27, 52] years, 40% female). Cardiac magnetic resonance images were analysed for mitral valve and annular abnormalities and late gadolinium enhancement. Clinical characteristics were compared between patients with and without MAD. MAD in any of the 4 locations was present in 112 (61%) IVF patients and inferolateral MAD was identified in 24 (13%) IVF patients. Mitral valve prolapse (MVP) was found in 13 (7%) IVF patients. MVP was more prevalent in patients with inferolateral MAD compared with patients without inferolateral MAD(42% vs. 2%, p < 0.001). Proarrhythmic characteristics in terms of a high burden of premature ventricular complexes (PVC) and non-sustained ventricular tachycardia (VT) were more prevalent in patients with inferolateral MAD compared to patients without inferolateral MAD (67% vs. 23%, p < 0.001 and 63% vs 41%, p = 0.046, respectively). Appropriate implantable cardioverter defibrillator therapy during follow-up was comparable for IVF patients with or without inferolateral MAD (13% vs. 18%, p = 0.579).

CONCLUSION

A high prevalence of inferolateral MAD and MVP is a consistent finding in this large IVF cohort. The presence of inferolateral MAD is associated with a higher PVC burden and non-sustained VTs. Further research is needed to explain this potential interplay.

Sudden cardiac arrest in infants and children: proposal for a diagnostic workup to identify the etiology. An 18-year multicenter evaluation in the Netherlands

Sudden cardiac arrest (SCA) studies are often population-based, limited to sudden cardiac death, and excluding infants. To guide prevention opportunities, it is essential to be informed of pediatric SCA etiologies. Unfortunately, etiologies frequently remain unresolved. The objectives of this study were to determine paediatric SCA etiology, and to evaluate the extent of post-SCA investigations and to assess the performance of previous cardiac evaluation in detecting conditions predisposing to SCA. In a retrospective cohort (2002-2019), all children 0-18 years with out-of-hospital cardiac arrest (OHCA) referred to Erasmus MC Sophia Children's Hospital or the Amsterdam UMC (tertiary-care university hospitals), with cardiac or unresolved etiologies were eligible for inclusion. SCA etiologies, cardiac and family history and etiologic investigations in unresolved cases were assessed. The etiology of arrest could be determined in 52% of 172 cases. Predominant etiologies in children ≥ 1 year (n = 99) were primary arrhythmogenic disorders (34%), cardiomyopathies (22%) and unresolved (32%). Events in children < 1 year (n = 73) were largely unresolved (70%) or caused by cardiomyopathy (8%), congenital heart anomaly (8%) or myocarditis (7%). Of 83 children with unresolved etiology a family history was performed in 51%, an autopsy in 51% and genetic testing in 15%. Pre-existing cardiac conditions presumably causative for SCA were diagnosed in 9%, and remained unrecognized despite prior evaluation in 13%.

CONCLUSION

SCA etiology remained unresolved in 83 of 172 cases (48%) and essential diagnostic investigations were often not performed. Over one-fifth of SCA patients underwent prior cardiac evaluation, which did not lead to recognition of a cardiac condition predisposing to SCA in all of them. The diagnostic post-SCA approach should be improved and the proposed standardized pediatric post-SCA diagnostics protocol may ensure a consistent and systematic evaluation process increasing the diagnostic yield.

WHAT IS KNOWN

• Arrests in infants remain unresolved in most cases. In children > 1 year, predominant etiologies are primary arrhythmia disorders, cardiomyopathy and myocarditis. • Studies investigating sudden cardiac arrest are often limited to sudden cardiac death (SCD) in 1 to 40 year old persons, excluding infants and successfully resuscitated children.

WHAT IS NEW

• In patients with unresolved SCA events, the diagnostic work up was often incompletely performed. • Over one fifth of victims had prior cardiac evaluation before the arrest, with either a diagnosed cardiac condition (9%) or an unrecognized cardiac condition (13%).

Different underlying aetiologies in patients presenting with ventricular tachycardia fulfilling task force criteria for ARVC: initial suspicion based on the 12-lead electrocardiogram

Background

The Task Force Criteria (TFC) for ARVC are highly sensitive, but lack specificity. Patients with atypical RV-involvement (aRVi) may have different underlying aetiologies and prognosis, requiring specific therapeutic interventions.

Purpose

We aimed to evaluate the role of the baseline ECG for initial suspicion of aRVi.

Methods

From the Netherlands Heart Institute Arrhythmogenic Cardiomyopathy (NHI-ACM) registry, patients were selected who 1) fulfilled TFC for definite ARVC, 2) presented with sustained VT, 3) underwent genetic testing. The first available ECG after VT was evaluated for AV-conduction and the presence and surface area (SA) of an R'-wave in V1-V3. ECGs with AV-conduction disturbances or an R'-wave with SA ≥1.65 mm2 were classified as suspicious for `atypical RV-involvement' (aRVi-ECG).

Patients with ARVC-related pathogenic/likely pathogenic variant (P/LP+) were classified as “typical ARVC”. Data of patients without an ARVC-related pathogenic/likely pathogenic variant (P/LP−) were reviewed by an expert panel and classified as either “typical ARVC” or “suggestive for another aetiology” based on consensus.

Results

In total 124 P/LP+ patients and 35 P/LP− patients were included. Nineteen patients had an aRVi-ECG, which appeared significantly more predominant in the P/LP− group (11 (9%) P/LP+ vs. 8 (22%) P/LP−, p=0.019). Of the P/LP− patients, seventeen (49%) were classified as “suggestive for another aetiology” (e.g. myocarditis, ischemia, sarcoid), including all 8 patients with an aRVI-ECG.

Among P/LP+ patients with an aRVi-ECG, 46% carried the Arg14del phospolamban variant and 64% died, versus 15% and 18% of P/LP+ patients without aRVi-ECG, respectively (Table 1).

Conclusion

For patients presenting with sustained VT and fulfilling the TFC for ARVC diagnosis, a baseline ECG suggestive for atypical RV-involvement should raise suspicion for a different underlying aetiology in patients without an ARVC-related P/LP variant. In P/LP+ patients, an aRVi-ECG may identify those with poor outcome.

Funding Acknowledgement

Type of funding sources: None.

Biophysical parameters and time to isolation of pulmonary veins with a novel cryoballoon: results of POLAR ICE study

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): Boston Scientific

Introduction

Low nadir temperatures and long thaw times with cryoballoon ablation are associated with successful pulmonary vein isolation (PVI). Recently, a system that maintains uniform pressure and size has been introduced to improve catheter stability during cryoballoon ablation. The present results examine the relationship between cryoballoon time to isolation (TTI) and other biophysical parameters; time to -40ºC (TT-40), nadir temperature, time to thaw (TT0), and first pass isolation success in patients with paroxysmal AF (PAF).

Methods

POLAR ICE, a prospective, non-randomized, multicenter (international) registry (NCT04250714), enrolled 400 patients across 19 centers, between Aug 2020 and May 2021. This study included any patients indicated for treatment of PAF with the POLARx cryoablation system. Cryodosing regimen was left to the operator and not specified by study protocol. Procedural characteristics, such as time to isolation (TTI), cryoablations per pulmonary vein, nadir temperature, and occlusion grade were recorded. PVI was confirmed via entrance block. Biophysical parameters for ablations longer than 120s were evaluated.

Results

Data on 389 PVI procedures (n=2303 ablations) were collected. Of those ablations, 1914 (83%) had a duration of at least 120s and were included in this analysis. Isolation was attempted using the CB alone. TTI was reported in 1335 ablations with the majority (64%) occurring within 60s. Biophysical parameters and single shot success rates were examined based on TTI. Ablations with TTI&lt;60s had significantly faster TT-40 (30.6±7.4s), lower nadir temperatures (-58.3±5.8ºC), longer thaw times (21.1±6.7s), and a greater proportion of grade 4 occlusions (88%) than longer TTIs or ablation with no TTI reported (Table 1). In TTIs&lt;60s single shot success was 95%, significantly greater than TT≥60s, or No TTI. Procedure-related complications included: phrenic nerve palsy (0.5%), tamponade (0.5%), AV block (0.3%), stroke (0.3%), and transient ischemic attack (0.3%).

Conclusions

These data suggest a correlation between cryoballoon biophysical parameters and single shot success. Good occlusion likely drives faster freeze and lower nadir temperatures, resulting in longer thaw times with this novel cryoballoon. Future research should examine the relationship between these parameters to drive optimization of cryoablation techniques and provide guidance toward improved workflow.

Acute procedural characteristics, efficacy, and safety of a novel cryoballoon for the treatment of paroxysmal atrial fibrillation: Results from the POLAR-ICE study

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): Boston Scientific

Background/Introduction

Pulmonary vein isolation (PVI) using a cryoballoon is well-established for the treatment of paroxysmal atrial fibrillation (PAF). Initial experience with a novel cryoballoon (CB) with a stable low balloon pressure (POLARx, Boston Scientific) has demonstrated acute procedural safety and efficacy in de novo PVI procedures in patients with paroxysmal AF. However, to date, there is limited multicenter data on real world acute outcomes and procedural characteristics with this novel cryoballoon.

Purpose

The purpose of POLAR ICE was to provide real-world data on the acute and chronic outcomes of cryoballoon ablation with POLARx for the treatment of PAF. Here we report on the initial acute outcomes up to 3 months including procedural efficacy, safety, and biophysical parameters.

Methods

POLAR ICE, a prospective, non-randomized, multicenter (international) registry (NCT04250714), enrolled 400 patients across 19 centers, between Aug 2020 and May 2021. This study included any patients indicated for treatment of PAF with the POLARx cryoablation system. The study protocol did not mandate any specific cryodosing regimen, this was left to the operator. Procedural characteristics, such as time to isolation (TTI), cryoablations per pulmonary vein, balloon nadir temperature, and occlusion grade were recorded. PVI was confirmed with entrance block testing.

Results

Complete PVI was achieved in 96.1% of PVs (1437/1496). Procedure and fluoroscopy times were 69.0±25.2 min and 15.8±10.0 min, respectively. Left atrial dwell time was 47.3±18.8 min. The cryoablation characteristics by vein are shown in the Table 1. An average of 4.9±1.8 ablations were performed per patient (1.3±0.7 per vein). Grade 3 or 4 occlusion was achieved in 98.1% of PVs reported. Electrical isolation was achieved with an average TTI of 50±33.8s and in 81.4% of PVs isolation required only a single cryoablation. Nadir temperatures across all pulmonary veins averaged -56.3± 6.5C. Time to -40C was 32.9±11s and Time to Thaw (0C) was 19.5±6.7s across all veins. PVI was performed on atypical anatomies (12 LCPV, 7 RMPV, & 3 RCPV) in 19 pts. Serious adverse events included phrenic nerve palsy (0.5%), tamponade (0.5%), AV block (0.3%), stroke (0.3%), and transient ischemic attack (0.3%).

Conclusions

Real world usage data on the novel CB suggests that this device is safe and effective, with a PV isolation success rate of 96.2% and 81.4% of PVs isolated with a single cryoablation. These data are in keeping with reports on other cryoballon systems and have markedly shorter procedure times than have been previously reported on this cryoballon.

A novel dipole charge density mapping system integrated in robotics offers advantages for ablation of atrial tachycardias: first-in-human experience

Funding Acknowledgements

Type of funding sources: None.

Background

Catheter ablation (CA) for atrial tachycardia (AT) and atrial flutter (AFL) offers favorable acute and long-term outcomes. Until recently, mapping of AT/AFL was only possible with sequential mapping methods using manually controlled catheters. Even by implementing multielectrode mapping, some limitations exist during mapping of short-lived arrhythmias and ATs with unstable CL. Remote magnetic navigation (RMN) with its atraumatic catheter design has superior safety profile and excellent accuracy. Recently, a novel high-resolution mapping system (AcQMap) can be used in combination with RMN (AcQMap-RMN).

Purpose

To assess the feasibility, safety and efficacy of AcQMap-RMN guided ablation in the management of complex ATs.

Methods

All patients undergoing CA for AT/AFL using AcQMap-RMN were included. The AcQMap system utilizes two different types of mapping: Single Position Map (SMP) and SuperMap, allowing mapping of both non-sustained and sustained ATs. Procedural efficiency was characterized by procedure time, total ablation time and radiation doses. Acute success was defined by arrhythmia source elimination. Efficacy data are based on 12-month follow up and number of redo procedures. Procedural safety was evaluated by intra- and post-procedural complications.

Results

A total number of 76 patients were referred for CA with AT/AFL (mean age 59.0±13.2), including 3 patients with inappropriate sinus tachycardia and 73 patients with AT/AFL. Out of 73 patients, 8 had perinodal AT. From the remaining 65 patients, 38 had de novo, 22 had post-PVI, and 5 patients had post-MAZE AT/AFL. Twenty-nine patients had short-lived ATs and were mapped exclusively by SPM. The mean procedure time was 175.9±61.4 min, mean ablation time 964.0 (IQR 422.0-1693.0) s, and mean radiation dose was 152.0(IQR 86.7-294.0) mGy. Acute success was documented in 70 procedures (92.1%). From de novo AT/AF patients 4 (10.5%), from post-PVI and post-MAZE AT/AFL patients 3 had recurrence at the end of the follow-up period (11.1%). Four patients had redo procedure. Three patients had post-procedural complications including 2 patients with groin hematoma and 1 patient with transient ischemic attack.

Conclusion

AcQMap-RMN integration offers improved efficiency, high success and low complication rates in complex AT ablation.

First human experience with catheter ablation using dipole charge density mapping integrated in robotics in the management of atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

Background

Remote magnetic navigation (RMN) guided catheter ablation (CA) previously demonstrated high efficiency and efficacy in atrial fibrillation (AF) ablation. Heretofore, only the CARTO 3D mapping system was integrated in the RMN system. Recently, a novel high-resolution non-contact mapping system (AcQMap) can be used in combination with the RMN robotic system (AcQMap-RMN).

Purpose

To assess efficiency, efficacy and safety of dipole charge density mapping in RMN guided ablation procedures for AF.

Methods

All patients undergoing pulmonary vein isolation (PVI) or redo-PVI using the AcQMap-RMN system were analyzed. The AcQMap identifies different activation patterns such as focal firing, rotational activity, and localized irregular activation for substrate ablation. Procedural efficiency was characterized by procedure time, total ablation time and radiation doses. Efficacy data were based on 12-month follow up and number of redo procedures. Procedural safety was evaluated by intra- and post-procedural complications.

Results

A number of 71 consecutive patients were included in the study (47 male, 24 female, mean age 60.8±9.9, 49 redo, 22 de novo). Twenty-four patients had paroxysmal (PAF), 47 had persistent AF (persAF). After completing PVI, 42 patients underwent AcQMap based substrate ablation. Twenty-four patients converted to atrial tachycardia/flutter during the ablation. The mean procedure time was 170.5±43.3 min, mean ablation time 1749.6±950.7 s, mean radiation dose was 207.0 (IQR 128.5 - 349.5) mGy. In the PAF group, radiation doses (128.5 vs 256.0 mGy, p=0.00) and application numbers (21.1 vs 37.0, p=0.00) were lower, ablation times were shorter (1312.5 vs 1919.3 s, p=0.02) compared to the persAF patient group. Two patients in the PAF group, and 9 patients in the persAF group had documented recurrence at the 6-month follow-up visits. In the PAF group, 23 patients were AF-free (95.8%), in the persAF group, 34 patients were AF-free at the end of the 12-month follow-up period (72.3%). Six patients had a redo procedure. Two patients were documented with hematoma, as minor post-procedural complication (2.8%).

Conclusion

AcQMap-RMN integration provides high acute and long-term success rates, improved efficiency and low complication rates in paroxysmal and persistent AF ablation.

Novel cryoballoon to isolate pulmonary veins in patients with paroxysmal atrial fibrillation: one-year outcomes in a multicenter study

Background

Recently, a novel cryoballoon (CB; POLARx) has been developed with increased steerability which maintains size and pressure throughout the ablation. Initial clinical data has demonstrated acute procedural safety and efficacy in de novo pulmonary vein isolation (PVI) procedures in patients with paroxysmal atrial fibrillation (AF). However, there are limited studies demonstrating the long-term efficacy of the CB.

Purpose

To evaluate the long-term safety and efficacy of the novel CB in treating paroxysmal AF.

Methods

This was a non-randomized, prospective, multi-center study. Fifty-eight consecutive patients with paroxysmal AF were enrolled at 4 centers for de novo PVI procedures. Cryoablation was delivered for 180s if time to isolation was ≤60s. Otherwise a 240s cryoablation was performed. PVI was confirmed with entrance and exit block testing. Patients were followed for 1 year with 24-hour Holter monitoring at 3, 6, and 12 months. After a 3-month blanking period, recurrence was defined as having any documented, symptomatic episode(s) of AF or atrial tachycardia.

Results

Acute isolation with the CB was achieved in 230 of 231 pulmonary veins (99.6%) with 5.2±1.5 cryoapplications per patient (1.3±0.6 cryoapplications per vein). There were 4 patients (6.9%) with phrenic nerve injury (3 resolved during the index procedure; 1 resolved at 6 months follow-up). One serious adverse device event was reported: femoral arterial embolism event occurring 2 weeks post index procedure (1.7%). Of the 56 patients that had complete 12-month follow-up, 43 (76.8%) were free from recurrent atrial arrhythmias.

Conclusion

Initial multicenter clinical experience with the novel CB has demonstrated long-term safety and efficacy of PVI in patients with paroxysmal AF. Further studies are underway to confirm these findings.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Boston Scientific

Sex-specific differences in outcome and risk stratification of ventricular arrhythmias in implantable cardioverter defibrillator patients

AIMS

Risk stratification models of sudden cardiac death (SCD) are based on the assumption that risk factors of SCD affect risk to a similar extent in both sexes. The aim of the study is to evaluate differences in clinical outcomes between sexes and evaluate whether risk factors associated with appropriate device therapy (ADT) differ between men and women.

METHODS AND RESULTS

We performed a cohort study of implantable cardioverter defibrillator (ICD) patients referred for primary or secondary prevention of SCD between 2009 and 2018. Multivariable Cox regression models for prediction of ADT were constructed for men and women separately. Of 2300 included patients, 571 (25%) were women. Median follow-up was 4.6 (inter-quartile range: 4.4-4.9) years. Time to ADT was shorter for men compared with women [hazard ratio (HR) 1.71, P < 0.001], as was time to mortality (HR 1.37, P = 0.003). In women, only secondary prevention ICD therapy (HR 1.82, P < 0.01) was associated with ADT, whereas higher age (HR 1.20, P < 0.001), absence of left bundle branch block (HR 0.72, P = 0.01), and secondary prevention therapy (HR 1.80, P < 0.001) were independently associated with ADT in men. None of the observed parameters showed a distinctive sex-specific pattern in ADT.

CONCLUSIONS

Male ICD patients were at higher risk of ADT and death compared with female ICD patients, irrespective of an ischaemic or non-ischaemic underlying cardiomyopathy. Our study highlights the importance to stratify outcomes of ICD trials by sex, as study results differ between men and women. However, none of the available clinical parameters showed a clear sex-specific relation to ventricular arrhythmias. As a consequence, sex-specific risk stratification models of SCD using commonly available clinical parameters could not be derived.

Infarct-related chronic total coronary occlusion and the risk of ventricular tachyarrhythmic events in out-of-hospital cardiac arrest survivors

Introduction

Chronic total coronary occlusion (CTO) has been identified as a risk factor for ventricular arrhythmias, especially a CTO in an infarct-related artery (IRA). This study aimed to evaluate the effect of an IRA-CTO on the occurrence of ventricular tachyarrhythmic events (VTEs) in out-of-hospital cardiac arrest survivors without ST-segment elevation.

Methods

We conducted a post hoc analysis of the COACT trial, a multicentre randomised controlled trial. Patients were included when they survived index hospitalisation after cardiac arrest and demonstrated coronary artery disease on coronary angiography. The primary endpoint was the occurrence of a VTE, defined as appropriate implantable cardioverter-defibrillator (ICD) therapy, sustained ventricular tachyarrhythmia or sudden cardiac death.

Results

A total of 163 patients from ten centres were included. Unrevascularised IRA-CTO in a main vessel was present in 43 patients (26%). Overall, 61% of the study population received an ICD for secondary prevention. During a follow-up of 1 year, 12 patients (7.4%) experienced at least one VTE. The cumulative incidence rate of VTEs was higher in patients with an IRA-CTO compared to patients without an IRA-CTO (17.4% vs 5.6%, log-rank p = 0.03). However, multivariable analysis only identified left ventricular ejection fraction < 35% as an independent factor associated with VTEs (adjusted hazard ratio 8.7, 95% confidence interval 2.2–35.4). A subanalysis focusing on CTO, with or without an infarct in the CTO territory, did not change the results.

Conclusion

In out-of-hospital cardiac arrest survivors with coronary artery disease without ST-segment elevation, an IRA-CTO was not an independent factor associated with VTEs in the 1st year after the index event.

Supplementary Information

The online version of this article (10.1007/s12471-021-01578-3) contains supplementary material, which is available to authorized users.

P1055Reduction of radiation exposure using an optimized fluoroscopy protocol in cryoballoon ablation does not compromise clinical outcome

Background/Introduction

Pulmonary vein isolation (PVI) using cryoballoon (CB) ablation is associated with an increased radiation exposure compared to radiofrequency ablation. Previous studies showed that radiation exposure in CB PVI can be reduced by optimizing the fluoroscopy protocol without comprising acute efficacy and safety.

Purpose

We evaluated the mid-term outcome of an optimized fluoroscopy protocol in patients undergoing CB PVI.

Methods

The study population comprised 90 consecutive patients who underwent second generation CB-based PVI. The first 46 patients underwent CB PVI with conventional fluoroscopy settings (Group A). In the following 44 patients (Group B) an optimized fluoroscopy protocol was applied consisting of 1) using fluoroscopy instead of filming for determining the pulmonary vein occlusion grade; and 2) optimal collimation of the area of interest. Primary endpoints were the total dose area product (DAP), fluoroscopy time and freedom from documented recurrence of atrial fibrillation (AF) after a single procedure.

Results

Group B had a lower median DAP (1393 cGycm2 vs. 3232 cGycm2, P &lt; 0.001) and median fluoroscopy time (20 min vs. 24 min, P &lt; 0.001) as compared to group A. The 1-year freedom from documented recurrence of AF after a single procedure was similar among groups (74% in Group A vs. 77% in Group B, P = 0.71). There were no significant differences between both groups for the secondary endpoints, including procedure duration, proportion of patients with complete electrical isolation, and complications.

Conclusion

Using an optimized fluoroscopy protocol in CB PVI radiation exposure could be reduced with a similar 1-year clinical outcome.

P2881Eligibility for a subcutaneous defibrillator based on standard 12-lead electrocardiogram

Background

Currently, the eligibility for a subcutaneous implantable defibrillator (S-ICD) system relies on a pre-implant vector screening based on the automated screening tool (AST).

Objective

To determine 12-lead ECG characteristics associated with eligibility for an S-ICD in a heterogeneous population at risk for sudden cardiac death (SCD). The goal is to determine patient eligibility for S-ICD using the standard 12-lead ECG, thereby avoiding additional AST screening.

Methods

We prospectively evaluated the eligibility for an S-ICD in 254 consecutive patients at risk for SCD. We identified 12-lead ECG parameters which were independently associated with AST passing (≥1 vector) using multivariable logistical regression analysis in our derivation cohort. The final model was tested in a separate validation cohort.

Results

The overall passing rate was 92% in our derivation cohort. Independent 12-lead ECG characteristics associated with AST passing were QRS≤130 ms, absence of QRS/T discordance in lead II and R/T-ratio ≥3.5 in lead II (Table). Eighty-three of 254 patients (33%) fulfilled these three criteria and had a passing rate of 100%. Of the validation cohort, 37 of 60 patients (62%) fulfilled all three criteria and also had a passing rate of 100%. The interobserver agreement for applying the ECG model was 90% (Cohen's Kappa=0.80).

Table 1 Variables Univariable Multivariable OR (95% CI) P-value OR (95% CI) P-value QRS ≤130 ms 9.65 (3.66–25.43) <0.01 8.09 (2.88–22.77) <0.01 QTc ≤450 ms 3.33 (1.18–9.54) 0.02 Absence of T-wave inversion in lead I 2.74 (1.03–7.25) 0.04 Absence of T-wave inversion in lead II 3.65 (1.29–10.33) 0.02 Absence of QRS/T-wave discordance in lead II 5.05 (1.98–12.92) <0.01 4.19 (1.49–11.74) <0.01 Absence of QRS/T-wave discordance in lead aVF 3.95 (1.53–10.19) <0.01 R/T-ratio ≥3.5 in lead II 3.58 (1.27–10.01) 0.02 4.21 (1.27–13.95) 0.02 R/T-ratio ≥3.5 in lead aVF 3.16 (1.18–8.42) 0.02 OR = odds ratio; CI = confidence interval.

Figure 1

Conclusion

Using the standard 12-lead ECG, we developed a simple screening model with a high specificity for S-ICD eligibility. Our results suggest that patients who fulfill the three ECG criteria do not need additional AST-screening. Therefore, we developed a simple flowchart to determine eligibility for an S-ICD that can be easily implemented in daily clinical practice (Figure).

P5428QRS narrowing more than 15 ms after CRT implantation is strongly associated with the long-term survival

Background

Cardiac resynchronization therapy (CRT) is used in selected heart failure patients with electrical cardiac dyssynchrony with a prolonged QRS duration and a left ventricle ejection fraction (LVEF) ≤35%. QRS duration post CRT implantation can probably predict responders and survivors. The aim of our study is to investigate the effect of QRS change on long-term survival post CRT implantation.

Methods

We performed a retrospective cohort study in patients receiving a CRT device in our tertiary referral center between January 2009 and January 2018. Clinical and electrocardiographic (ECG) data were collected at baseline, one week after CRT implantation, six months, and yearly during follow-up. The primary endpoint was death, left ventricle assisting device implantation, or heart transplantation. At the end, the cohort was dichotomized to the cut-off value of ≥15ms according current literature.

Results

The study population consisted of 219 patients of whom 145 (66%) patients were survivors and 74 (34%) non-survivors. Non-survivors were significantly older (63 vs. 68 years, p=0.001), male gender (67% vs. 82%, p=0.015), had more often diabetes mellitus (20% vs. 39%, p=0.002), chronic obstructive pulmonary disease (12% vs. 28%, p=0.003), an ischemic etiology of heart failure (42% vs. 61%, p=0.009) with previous myocardial infarction (29% vs 53%, p=0.001), previous revascularization (32% vs. 49%, p=0.019), atrial fibrillation (21% vs. 39%, p=0.004), worser NYHA class (p=0.008), and amiodarone use (10% vs. 22%, p=0.024). Blood urea nitrogen (BUN) (8.1 mmol/L vs. 10.4 mmol/L, p<0.001) and creatinine levels (96 μmol/L vs. 114 μmol/L, p=0.001) were also higher in the non-survivors group. Median QRS duration (168 ms IQR [154 to 182]) at baseline was comparable between survivors and non-survivors (170 ms vs. 166 ms, p=0.17). However, median QRS change one week after CRT implantation was significantly better in the survivors (−19 ms IQR [−30 to −2] vs. −6 ms IQR [−24 to +12], p=0.004). The QRS change at the last FU (median 5.1 years IQR [2.9 to 7.8] was consistently higher in the survivor group (−16 ms IQR [−29 to 0] vs. +1 ms IQR [−27 to +20], p=0.004). Dichotomized to ΔQRS narrowing of ≥15 ms after CRT implantation showed significantly better long-term survival (figure).

Kaplan-Meier curve

Conclusion

QRS narrowing cut-off of ≥15 ms post CRT implantation is strongly associated with the long term survival in chronic heart failure patients with reduced LVEF.

P5421Prevalence of electromagnetic interference from left ventricular assist devices in patients with implantable cardioverter defibrillator/pacemakers

Background

Many patients eligible for left ventricular assist device (LVAD) therapy already have an implantable cardioverter defibrillator (ICD) and/or pacemaker (PM). However, electromagnetic interference (EMI) between the LVAD and ICD/PM devices could be cumbersome.

Purpose

The aim of this study was to investigate the prevalence of EMI between different types of ICD/PM in patients implanted with an LVAD.

Methods

Data was obtained through a retrospective electronic patient database analysis of all LVAD patients (including HeartMate II (HMII) and HeartMate 3 (HM3)), from our tertiary referral center, from December 2006 to February 2019. Device switches have also been taken into account due to elective replacement. Electromagnetic interference was defined as ICD/PM telemetry interference (i.e. the inability to interrogate ICD/PM)

Results

In total, 109 patients received an LVAD (mean age 52±12, 83% male), Of these, 86 (79%) patients had an ICD/PM at LVAD implantation. One patient with ICD/PM was excluded from further analysis because of missing follow-up data. Among the 85 patients (45 HM II and 40 HM3), 11 (13%) experienced EMI; 5 (11%) with a HM II and 6 (15%) with a HM3 (p=0.59). The implanted ICD/PM devices were from Medtronic (n=25), Abbott (n=23), Biotronik (n=18), Boston Scientific (n=18), and Microport (n=1). EMI with the HM II was present in St Jude/Abbott devices (type 1 Atlas, 1 Unify, 1 Fortify, and 2 Promote). In HM 3 LVAD patients, EMI was observed in Biotronik devices (1 Lumax, 1 Ilivia, 1 Ilesto, and 2 Iperia) and Medtronic (Claria).

Conclusion

In our cohort of HM II and HM 3 LVAD patients, at least one in seven patients experienced EMI from either the HM II or HM3 LVAD with the ICD/PM. Electromagnetic interference from HM II LVADs was mainly present in patients with St Jude/Abbott ICD/PM devices However, in the HM3 patients, EMI was mainly present in patients with Biotronik devices, which is not yet widely known!

Procedural and long-term outcome after catheter ablation of idiopathic outflow tract ventricular arrhythmias: comparing manual, contact force, and magnetic navigated ablation

Aims

Currently, comparative data on procedural and long-term clinical outcome of outflow tract (OT) idiopathic ventricular arrhythmia (IVA) ablation with manual (MAN), contact force (CF), and magnetic navigation system (MNS) ablation are lacking. The aim of this study was to compare the procedural and long-term clinical outcome of MAN, CF, and MNS ablation of OT IVAs.

Methods and results

Seventy-three patients (31 MAN, 17 CF, and 25 MNS patients; consecutive per group) with OT IVA, who underwent catheter ablation in our centre were analysed. Procedural success rates (success at the end of the procedure), procedural data and long-term follow-up data were compared. Baseline patient demographics were comparable. Procedural success rates were similar (MAN 81%, 71% CF, and MNS 92%; P = 0.20). Median fluoroscopy time was shorter in the MNS group: MAN 29 (16-38), CF 37 (21-46), and MNS 13 (10-20) min (P = 0.002 for MNS vs. CF and MAN). The overall complication rate was: MAN 10%, CF 0%, and MNS 0% (P = 0.12). Median follow-up was: MAN 2184 (1672-2802), CF 1721 (1404-1913), and MNS 3031 (2524-3286) days (P <0.001). Recurrences occurred in MAN 46%, CF 50%, and MNS 46% (P = 0.97). Repeat procedures were performed in MAN 20%, CF 40%, and MNS 33% (P = 0.32).

Conclusion

Procedural and long-term clinical outcome of OT IVA ablation are equal for MAN, CF, and MNS. MNS has a favourable procedural safety profile due to the shorter fluoroscopy time compared with MAN and CF.

Multiplane/3D transesophageal echocardiography monitoring to improve the safety and outcome of complex transvenous lead extractions

Both transesophageal echocardiography (TEE) and intracardiac echocardiography have been used to assist transvenous lead extractions. The clinical utility of continuous echocardiographic monitoring during the procedure is still debated, with different reports supporting opposite findings. In cases where the procedure is expected to be difficult, we propose adding a continuous TEE monitoring using a static 3D/multiplane probe in mid-esophageal position, with digital remote manipulation of the field of view. This approach may improve the chances of a successful extraction, increase safety, or even guide the entire intervention. We present here a short case series where continuous monitoring by TEE played an important role.

Minimally interrupted novel oral anticoagulant versus uninterrupted vitamin K antagonist during atrial fibrillation ablation

PURPOSE

The safety and efficacy of a minimally interrupted novel oral anticoagulant (NOAC) strategy at the time of atrial fibrillation (AF) ablation is uncertain. The purpose of this study was to compare rates of bleeding and thromboembolic events between minimally interrupted NOAC and uninterrupted vitamin K antagonist (VKA) in patients undergoing AF ablation.

METHODS

This was a retrospective single-center cohort study of consecutive patients who underwent AF catheter ablation between January 2013 and April 2017. Endpoints included major bleeding, clinically relevant non-major bleeding and systemic thromboembolic event from the time of ablation through 30 days. Bleeding events were defined by the Bleeding Academic Research Consortium (BARC) and International Society on Thrombosis and Haemostasis (ISTH).

RESULTS

A total of 637 patients were included in the analysis, 520 patients used uninterrupted VKA and 117 patients minimally interrupted NOAC (dabigatran: n = 68; apixaban: n = 30; rivaroxaban, n = 14; edoxaban, n = 5). The rate of clinically relevant non-major bleeding was lower in the NOAC group in comparison to the VKA group (BARC type 2: 2.6% versus 8.3%, P = 0.03; ISTH: 0% versus 3.8%, P = 0.03). Rates of major bleeding were similar between groups (BARC type 3 to 5: 3.4% versus 4.2%, P = NS; ISTH: 6.0% versus 8.7%, P = NS; for NOAC and VKA groups, respectively). Rates of systemic embolism were 0% with minimally interrupted NOAC, and 0.6% with uninterrupted VKA (P = NS).

CONCLUSIONS

In patients undergoing AF ablation, anticoagulation with minimally interrupted NOAC was associated with fewer clinically relevant non-major bleeding events in comparison with uninterrupted VKA without compromising thromboembolic safety.

Comparative study of the failure rates among 3 implantable defibrillator leads

BACKGROUND

After the introduction of the Biotronik Linox S/SD high-voltage lead, several cases of early failure have been observed.

OBJECTIVE

The purpose of this article was to assess the performance of the Linox S/SD lead in comparison to 2 other contemporary leads.

METHODS

We used the prospective Erasmus MC ICD registry to identify all implanted Linox S/SD (n = 408), Durata (St. Jude Medical, model 7122) (n = 340), and Endotak Reliance (Boston Scientific, models 0155, 0138, and 0158) (n = 343) leads. Lead failure was defined by low- or high-voltage impedance, failure to capture, sense or defibrillate, or the presence of nonphysiological signals not due to external interference.

RESULTS

During a median follow-up of 5.1 years, 24 Linox (5.9%), 5 Endotak (1.5%), and 5 Durata (1.5%) leads failed. At 5-year follow-up, the cumulative failure rate of Linox leads (6.4%) was higher than that of Endotak (0.4%; P < .0001) and Durata (2.0%; P = .003) leads. The incidence rate was higher in Linox leads (1.3 per 100 patient-years) than in Endotak and Durata leads (0.2 and 0.3 per 100 patient-years, respectively; P < .001). A log-log analysis of the cumulative hazard for Linox leads functioning at 3-year follow-up revealed a stable failure rate of 3% per year. The majority of failures consisted of noise (62.5%) and abnormal impedance (33.3%).

CONCLUSION

This study demonstrates a higher failure rate of Linox S/SD high-voltage leads compared to contemporary leads. Although the mechanism of lead failure is unclear, the majority presents with abnormal electrical parameters. Comprehensive monitoring of Linox S/SD high-voltage leads includes remote monitoring to facilitate early detection of lead failure.

[Domperidone to promote lactation]

- Breast milk is the best diet for all newborns, especially premature newborns.- In case of insufficient production of breast milk, feeding and extraction techniques should be optimized first, preferably supported by a lactation consultant. When supportive measures fail, domperidone to promote milk production can be considered.- The risk of side effects in newborns is negligible. The risk of maternal arrhythmias associated with QTc prolongation is low as long as domperidone is prescribed in low doses (10 mg tds).- In the absence of risk factors it is not necessary to routinely perform an ECG and, therefore, general practitioners can safely prescribe domperidone.- The effect of the treatment should be evaluated after 2 weeks. In case of prolonged treatment or use of higher dosages, it is recommended to perform an ECG to exclude QTc prolongation.

Surgical outcome of discrete subaortic stenosis in adults: a multicenter study

BACKGROUND

Discrete subaortic stenosis is notable for its unpredictable hemodynamic progression in childhood and high reoperation rate; however, data about adulthood are scarce.

METHODS AND RESULTS

Adult patients who previously underwent surgery for discrete subaortic stenosis were included in this retrospective multicenter cohort study. Mixed-effects and joint models were used to assess the postoperative progression of discrete subaortic stenosis and aortic regurgitation, as well as reoperation. A total of 313 patients at 4 centers were included (age at baseline, 20.2 years [25th-75th percentile, 18.4-31.0 years]; 52% male). Median follow-up duration was 12.9 years (25th-75th percentile, 6.2-20.1 years), yielding 5617 patient-years. The peak instantaneous left ventricular outflow tract gradient decreased from 75.7±28.0 mm Hg preoperatively to 15.1±14.1 mm Hg postoperatively (P<0.001) and thereafter increased over time at a rate of 1.31±0.16 mm Hg/y (P=0.001). Mild aortic regurgitation was present in 68% but generally did not progress over time (P=0.76). A preoperative left ventricular outflow tract gradient ≥80 mm Hg was a predictor for progression to moderate aortic regurgitation postoperatively. Eighty patients required at least 1 reoperation (1.8% per patient-year). Predictors for reoperation included female sex (hazard ratio, 1.53; 95% confidence interval, 1.02-2.30) and left ventricular outflow tract gradient progression (hazard ratio, 1.45; 95% confidence interval, 1.31-1.62). Additional myectomy did not reduce the risk for reoperation (P=0.92) but significantly increased the risk of a complete heart block requiring pacemaker implantation (8.1% versus 1.7%; P=0.005).

CONCLUSIONS

Survival is excellent after surgery for discrete subaortic stenosis; however, reoperation for recurrent discrete subaortic stenosis is not uncommon. Over time, the left ventricular outflow tract gradient slowly increases and mild aortic regurgitation is common, although generally nonprogressive over time. Myectomy does not show additional advantages, and because it is associated with an increased risk of complete heart block, it should not be performed routinely.

Effects of rosuvastatin on progression of stenosis in adult patients with congenital aortic stenosis (PROCAS Trial)

Recent trials have failed to show that statin therapy halts the progression of calcific aortic stenosis (AS). We hypothesized that statin therapy in younger patients with congenital AS would be more beneficial, because the valve is less calcified. In the present double-blind, placebo-controlled trial, 63 patients with congenital AS (age 18 to 45 years) were randomly assigned to receive either 10 mg of rosuvastatin daily (n = 30) or matched placebo (n = 33). The primary end point was the progression of peak aortic valve velocity. The secondary end points were temporal changes in the left ventricular mass, ascending aortic diameter, and N-terminal pro-brain natriuretic peptide (NT-proBNP). The median follow-up was 2.4 years (interquartile range 1.9 to 3.0). The mean increase in peak velocity was 0.05 ± 0.21 m/s annually in the rosuvastatin group and 0.09 ± 0.24 m/s annually in the placebo group (p = 0.435). The annualized change in the ascending aorta diameter (0.4 ± 1.7 mm with rosuvastatin vs 0.5 ± 1.6 mm with placebo; p = 0.826) and left ventricular mass (1.1 ± 15.8 g with rosuvastatin vs -3.7 ± 30.9 g with placebo; p = 0.476) were not significantly different between the 2 groups. Within the statin group, the NT-proBNP level was 50 pg/ml (range 19 to 98) at baseline and 21 pg/ml (interquartile range 12 to 65) at follow-up (p = 0.638). NT-proBNP increased from 40 pg/ml (interquartile range 20 to 92) to 56 pg/ml (range 26 to 130) within the placebo group (p = 0.008). In conclusion, lipid-lowering therapy with rosuvastatin 10 mg did not reduce the progression of congenital AS in asymptomatic young adult patients. Interestingly, statins halted the increase in NT-proBNP, suggesting a potential positive effect of statins on cardiac function in young patients with congenital AS.

Smoking and its effects on mortality in adults with congenital heart disease

AIMS

To describe smoking habits in adults with congenital heart disease (ACHD) and to assess the relationship between smoking exposure and cardiovascular mortality.

METHODS

Data on smoking history and cardiovascular mortality were extracted from the Euro Heart Survey on adult congenital heart disease - a retrospective cohort study, that included patients diagnosed with 1 of 8 subgroups of ACHD (Atrial Septal Defects, Ventricular Septal Defects, Marfan Syndrome, Aortic Coarctation, Tetralogy of Fallot (ToF), Transposition of the Great Arteries (TGA), Fontan circulation, and Cyanotic disease).

RESULTS

Complete data of 3375 ACHD patients (median age 28 years) were available for analysis. At inclusion, 9.3% (n=314) were current smokers and 4.2% (n=142) of the patients had smoked in the past. During a median follow-up of 5.1 years, 101 patients (3%) died. In the majority of cases the cause of death was cardiovascular (n=81; 80%). Kaplan-Meier and Cox survival analysis for each of the defects separately showed a significantly increased age and sex-adjusted cardiovascular mortality associated with smoking exposure in TGA patients (Hazard ratio 4.2 (95% CI 1.0-16.8); P=0.044). Also in ToF mortality was higher amongst smokers, though not significantly (HR 3.4 (95% CI 0.6-18.5); P=0.15). In the remaining defects no relationship between smoking and cardiovascular mortality was observed.

CONCLUSION

The prevalence of smoking amongst ACHD patients is relatively low. Smoking exposure is associated with increased cardiovascular mortality in patients with TGA. Prospective long-term follow-up studies are necessary.

Fertility, Pregnancy and Delivery in Women after Biventricular Repair for Double Outlet Right Ventricle

OBJECTIVES

To investigate outcome of pregnancy and fertility in women with double outlet right ventricle (DORV).

METHODS

Using 2 congenital heart disease registries, 21 female patients with DORV (aged 18-39 years) were retrospectively identified. Detailed recordings of each patient and their completed (>20 weeks gestation) pregnancies were recorded.

RESULTS

Overall, 10 patients had 19 pregnancies, including 3 spontaneous miscarriages (16%). During the 16 live birth pregnancies, primarily (serious) noncardiac complications were observed, e.g. premature labor/delivery (n = 7 and n = 3, respectively), small for gestational age (n = 4), preeclampsia (n = 2) and recurrence of congenital heart disease (n = 2). Except for postpartum endocarditis and deterioration of subpulmonary obstruction, only mild cardiac complication pregnancies were recorded. Two women with children reported secondary female infertility. Several menstrual cycle disorders were reported: secondary amenorrhea (n = 4), primary amenorrhea (n = 3) and oligomenorrhea (n = 2).

CONCLUSION

Successful pregnancy in women with DORV is possible. Primarily noncardiac complications were observed and only few (minor) cardiac complications. Infertility and menstrual cycle disorders appear to be more prevalent.

Outcome of pregnancy in women with congenital heart disease: a literature review

A search of peer-reviewed literature was conducted to identify reports that provide data on complications associated with pregnancy in women with structural congenital heart disease (CHD). This review describes the outcome of 2,491 pregnancies, including 377 miscarriages (15%) and 114 elective abortions (5%). Important cardiac complications were seen in 11% of the pregnancies. Obstetric complications do not appear to be more prevalent. In complex CHD, premature delivery rates are high, and more children are small for gestational age. The offspring mortality was high throughout the spectrum and was related to the relatively high rate of premature delivery and recurrence of CHD.

Oxidative susceptibility of low density lipoprotein from rabbits fed atherogenic diets containing coconut, palm, or soybean oils

The oxidative susceptibilities of low density lipoproteins (LDL) isolated from rabbits fed high-fat atherogenic diets containing coconut, palm, or soybean oil were investigated. New Zealand white rabbits were fed atherogenic semisynthetic diets containing 0.5% cholesterol and either (i) 13% coconut oil and 2% corn oil (CNO), (ii) 15% refined, bleached, and deodorized palm olein (RBDPO), (iii) 15% crude palm olein (CPO), (iv) 15% soybean oil (SO), or (v) 15% refined, bleached, and deodorized palm olein without cholesterol supplementation [RBDPO(wc)], for a period of twelve weeks. Total fatty acid compositions of the plasma and LDL were found to be modulated (but not too drastically) by the nature of the dietary fats. Cholesterol supplementation significantly increased the plasma level of vitamin E and effectively altered the plasma composition of long-chain fatty acids in favor of increasing oleic acid. Oxidative susceptibilities of LDL samples were determined by Cu2(+)-catalyzed oxidation which provide the lag times and lag-phase slopes. The plasma LDL from all palm oil diets [RBDPO, CPO, and RBDPO(wc)] were shown to be equally resistant to the oxidation, and the LDL from SO-fed rabbits were most susceptible, followed by the LDL from the CNO-fed rabbits. These results reflect a relationship between the oxidative susceptibility of LDL due to a combination of the levels of polyunsaturated fatty acids and vitamin E.

The short-chain homologue of dihydrolipoic acid, tetranordihydrolipoate, protects against iron-induced lipid peroxidation in the aqueous phase

Because iron is involved in catalysis of many biological oxidations, it is important to investigate new and novel antioxidants in terms of their effect on iron-catalyzed oxidations. We investigated the effect of dihydrolipoic acid (6,8-dimercaptooctanoic acid (DHLA)), its homologues (4,6-dimercaptohexanoic acid (bisnorDHLA) and 2,4-dimercaptobutanoic acid (tetranorDHLA)) and methyl 6,8-dimercaptooctanoate (methylDHLA) on Fe(II)-citrate-catalyzed lipid peroxide-dependent lipid peroxidation in lipid-dispersed and liposome systems. In the lipid-dispersed system, tetranorDHLA inhibited conjugated diene formation induced by Fe(II)-citrate. In the presence of tetranorDHLA, oxygen was consumed more rapidly in the reaction mixture than in the presence of the other compounds, but the oxidation rate of Fe(II)-citrate in the reaction mixture was slower than in the presence of the other compounds. This suggests that tetranorDHLA inhibited lipid peroxidation by the oxidation of tetranorDHLA itself at the site where the lipid was oxidized.

Pulsed-field gel electrophoresis for differentiation of hospital isolates of Klebsiella pneumoniae

Restriction enzyme analysis by pulsed-field gel electrophoresis (PFGE) was developed for differentiation of hospital isolates of Klebsiella pneumoniae. Restriction patterns generated by SpeI digestion of genomic DNAs of 36 isolates from patients in two major teaching hospitals established 34 PFGE types. All strains were typable by this technique and the SpeI restriction patterns were reproducible, stable and easy to interpret. As PFGE profiles generated were heterogenous, the incidence of cross-infection appeared to be low in each of the hospitals. The higher discriminatory power of PFGE when compared to conventional restriction endonuclease analysis (REA) suggests that this technique will be very useful for epidemiological investigations of nosocomial K. pneumoniae outbreaks.