Impact of ventricular tachycardia ablation in subcutaneous implantable cardioverter defibrillator carriers: a multicentre, international analysis from the iSUSI project

AIMS

Catheter ablation (CA) of ventricular tachycardia (VT) has become an important tool to improve clinical outcomes in patients with appropriate transvenous implantable cardioverter defibrillator (ICD) shocks. The aim of our analysis was to test whether VT ablation (VTA) impacts long-term clinical outcomes even in subcutaneous ICD (S-ICD) carriers.

METHODS AND RESULTS

International Subcutaneous Implantable Cardioverter Defibrillator (iSUSI) registry patients who experienced either an ICD shock or a hospitalization for monomorphic VT were included in this analysis. Based on an eventual VTA after the index event, patients were divided into VTA+ vs. VTA- cohorts. Primary outcome of the study was the occurrence of a combination of device-related appropriate shocks, monomorphic VTs, and cardiovascular mortality. Secondary outcomes were addressed individually. Among n = 1661 iSUSI patients, n = 211 were included: n = 177 experiencing ICD shocks and n = 34 hospitalized for VT. No significant differences in baseline characteristics were observed. Both the crude and the yearly event rate of the primary outcome (5/59 and 3.8% yearly event rate VTA+ vs. 41/152 and 16.4% yearly event rate in the VTA-; log-rank: P value = 0.0013) and the cardiovascular mortality (1/59 and 0.7% yearly event rate VTA+ vs. 13/152 and 4.7% yearly event rate VTA-; log-rank P = 0.043) were significantly lower in the VTA + cohort. At multivariate analysis, VTA was the only variable remaining associated with a lower incidence of the primary outcome [adjusted hazard ratio 0.262 (0.100-0.681), P = 0.006].

CONCLUSION

In a real-world registry of S-ICD carriers, the combined study endpoint of arrhythmic events and cardiovascular mortality was lower in the patient cohort undergoing VTA at long-term follow-up.

CLINICALTRIALS.GOV IDENTIFIER

NCT0473876.

Atrial fibrillation recurrences during the blanking period after catheter ablation with the laser balloon technique

INTRODUCTION

Regardless of the catheter ablation (CA) for atrial fibrillation (AF) strategy, the role of early recurrences during the blanking period (BP) is still unclear. Our aim was to evaluate atrial tachyarrhythmias (ATAs) recurrences during the BP after CA with the laser-balloon (LB) technique.

METHODS

Consecutive patients undergoing LBCA were enrolled. Primary outcome of the study was the overall crude ATA recurrence rate during the BP. ATA recurrences after the BP and in-hospital readmissions during the BP were deemed secondary outcomes.

RESULTS

Two hundred and twenty-four patients underwent CA with the LB. Median age was 63.0 (55.5-69.5) years and 74.1% were males. 28.6% were persistent AF patients, and 34.8% of patients were followed up with a loop recorder. 15.6% of patients experienced at least an ATA recurrence during the BP. Male sex, chronic heart failure, persistent AF, and recurrences during the BP were found to be associated with long-term ATA recurrences. Recurrences during the BP remained associated with the outcome of interest at multivariate analysis (hazard ratio [HR] = 12.393, 95% confidence interval [95% CI] = 3.699-41.865, p < .001). An association over time was found between early and late recurrences, with 73.7%, 45.5%, and 10.8% of patients presenting with recurrences at 1-, 2-, and 3-month follow-up being free from recurrences after the BP, respectively. 8.0% of patients were readmitted during the BP: 4.5% for AF electrical cardioversion, and 1.8% for CA of other atrial arrhythmias; no redo CA was performed.

CONCLUSION

After adjusting for confounders, ATA recurrences during the BP represent the most significant predictor of ATA recurrences after the BP, regardless of AF pattern.

Sex differences in leadless pacemaker implantation: A propensity-matched analysis from the i-LEAPER registry

BACKGROUND

The impact of sex in clinical and procedural outcomes in leadless pacemaker (LPM) patients has not yet been investigated.

OBJECTIVE

The purpose of this study was to investigate sex-related differences in patients undergoing LPM implantation.

METHODS

Consecutive patients enrolled in the i-LEAPER registry were analyzed. Comparisons between sexes were performed within the overall cohort using an adjusted analysis with 1:1 propensity matching for age and comorbidities. The primary outcome was the comparison of major complication rates. Sex-related differences regarding electrical performance and all-cause mortality during follow-up were deemed secondary outcomes.

RESULTS

In the overall population (n = 1179 patients; median age 80 years), 64.3% were men. After propensity matching, 738 patients with no significant baseline differences among groups were identified. During median follow-up of 25 [interquartile range 24-39] months, female sex was not associated with LPM-related major complications (hazard ratio [HR] 2.03; 95% confidence interval [CI] 0.70-5.84; P = .190) or all-cause mortality (HR 0.98; 95% CI 0.40-2.42; P = .960). LPM electrical performance results were comparable between groups, except for a higher pacing impedance in women at implant and during follow-up (24 months: 670 [550-800] Ω vs 616 [530-770] Ω; P = .014) that remained within normal limits.

CONCLUSION

In a real-world setting, we found differences in sex-related referral patterns for LPM implantation with an underrepresentation of women, although major complication rate and LPM performance were comparable between sexes. Female patients showed higher impedance values, which had no impact on overall device performance. Electrical parameters remained within normal limits in both groups during the entire follow-up.

Outcomes of leadless pacemaker implantation following transvenous lead extraction in high-volume referral centers: Real-world data from a large international registry

BACKGROUND

Limited data on the real-world safety and efficacy of leadless pacemakers (LPMs) post-transvenous lead extraction (TLE) are available.

OBJECTIVE

The purpose of this study was to assess the long-term safety and effectiveness of LPMs following TLE in comparison with LPMs de novo implantation.

METHODS

Consecutive patients who underwent LPM implantation in 12 European centers joining the International LEAdless PacemakEr Registry were enrolled. The primary end point was the comparison of LPM-related complication rate at implantation and during follow-up (FU) between groups. Differences in electrical performance were deemed secondary outcomes.

RESULTS

Of the 1179 patients enrolled, 15.6% underwent a previous TLE. During a median FU of 33 (interquartile range 24-47) months, LPM-related major complications and all-cause mortality did not differ between groups (TLE group: 1.6% and 5.4% vs de novo group: 2.2% and 7.8%; P = .785 and P = .288, respectively). Pacing threshold (PT) was higher in the TLE group at implantation and during FU, with very high PT (>2 V@0.24 ms) patients being more represented than in the de novo implantation group (5.4% vs 1.6 %; P = .004). When the LPM was deployed at a different right ventricular (RV) location than the one where the previous transvenous RV lead was extracted, a lower proportion of high PT (>1-2 V@0.24 ms) patients at implantation, 1-month FU, and 12-month FU (5.9% vs 18.2%, P = .012; 3.4% vs 12.9%, P = .026; and 4.3% vs 14.5%, P = .037, respectively) was found.

CONCLUSION

LPMs showed a satisfactory safety and efficacy profile after TLE. Better electrical parameters were obtained when LPMs were implanted at a different RV location than the one where the previous transvenous RV lead was extracted.

Peri-procedural and mid-term follow-up age-related differences in leadless pacemaker implantation: Insights from a multicenter European registry

BACKGROUND

Age-related differences on leadless pacemaker (LP) are poorly described. Aim of this study was to compare clinical indications, periprocedural and mid-term device-associated outcomes in a large real-world cohort of LP patients, stratified by age at implantation.

METHODS

Two cohorts of younger and older patients (≤50 and > 50 years old) were retrieved from the iLEAPER registry. The primary outcome was to compare the underlying indication why a LP was preferred over a transvenous PM across the two cohorts. Rates of peri-procedural and mid-term follow-up major complications as well as LP electrical performance were deemed secondary outcomes.

RESULTS

1154 patients were enrolled, with younger patients representing 6.2% of the entire cohort. Infective and vascular concerns were the most frequent characteristics that led to a LP implantation in the older cohort (45.8% vs 67.7%, p < 0.001; 4.2% vs 16.4%, p = 0.006), while patient preference was the leading cause to choose a LP in the younger (47.2% vs 5.6%, p < 0.001). Median overall procedural (52 [40-70] vs 50 [40-65] mins) and fluoroscopy time were similar in both groups. 4.3% of patients experienced periprocedural complications, without differences among groups. Threshold values were higher in the younger, both at discharge and at last follow-up (0.63 [0.5-0.9] vs 0.5 [0.38-0-7] V, p = 0.004).

CONCLUSION

When considering LP indications, patient preference was more common in younger, while infective and vascular concerns were more frequent in the older cohort. Rates of device-related complications did not differ significantly. Younger patients tended to have a slightly higher pacing threshold at mid-term follow-up.

929 LEADLESS PACEMAKER IMPLANTATION FOLLOWING TRANSVENOUS LEAD EXTRACTION: DATA FROM HIGH-VOLUME REFERRAL CENTERS

Background

limited data on real-world safety and efficacy of leadless pacemakers (LPMs) in patients who underwent transvenous lead extraction (TLE) are currently available. The present study aims to assess long-term safety and efficacy of LPMs implantation following TLE, compared with LPM de novo implant patients.

Methods

consecutive patients who underwent LPM implantation in 12 centers joining the International LEAdless PacemakEr (i-LEAPER) registry were enrolled end retrospectively considered. Patients receiving LPM following TLE (n=184) were compared with patients with de novo implant (n=995). The primary endpoint was LPM-related complications rate at implant and during follow-up (FU). Additionally, differences in electrical performance were assessed between the two groups.

Results

1179 patients were enrolled in this study and followed for a median of 33 months. LPM related major complications and all-cause mortality did not differ among the two groups (1.6% TLE group vs. 2.2% de novo group, p=0.785, and 5.4% TLE group vs. 7.8% de novo group, p=0.288, respectively). Pacing threshold (PT) resulted higher in the TLE group throughout the whole follow-up (FU) (Figure 1). Higher PTs were recorded in LPMs implanted at same location from where the previous transvenous lead was removed, as far as 24-months postimplant (Figure 2), with a higher proportion of patients with high PT (&gt;1 to 2V @0.24ms) in the first group at implant, 1-month, and 12-month FU (Figure 3).

Conclusion

In this real-world registry, LPMs showed a satisfactory safety and efficacy profile after TLE. In the post-TLE cohort, better electrical parameters were obtained when LPMs were implanted at a different location from where the previous transvenous lead was extracted.

Long term comparisons of atrial fibrillation ablation outcomes with a cryo-balloon or laser-balloon: a propensity-matched analysis based on continuous rhythm monitoring

BACKGROUND

Cryoballoon (CB) and laser-balloon (LB) catheter ablation (CA) have been demonstrated to achieve durable and effective pulmonary vein isolation (PVI). Only one head-to-head comparison with an intermittent rhythm monitor strategy is currently available. Aim of this study was to compare acute and long-term outcomes of CB and LB atrial fibrillation ablation procedures, using a continuous rhythm monitoring strategy.

METHODS

This was a prospective two-arm non-randomized propensity-matched observational trial, comparing the outcomes of atrial fibrillation (AF) ablation using LB and CB techniques. To evaluate AF recurrences, an implantable cardiac monitor (ICM) was implanted prior to hospital discharge to detect atrial tachyarrhythmias (ATAs) recurrences.

RESULTS

110 propensity-matched patients undergoing AF ablation with a LB (n=55) or with a CB system (n=55) were enrolled (paroxysmal AF 57.3%). Procedural time (LB: 87 [73-104] vs CB 90 [70-130] min; p=0.264) and fluoroscopy time did not differ. No differences in ATAs recurrences were observed at 12-month (LB-30.9% vs CB-29.1% and LB-45.5% vs CB-38.2%; log-rank 0.539). As for AF burden, the 12-month median was 0 [0-1] vs 0 [0-3]% (p=0.127), in the LB and CB-group, respectively. When considering only PeAF patients, median 12-month ATAs burden was 26 [18.5-40.5] vs 29 [26-35] % for the LB and CB patients (p=0.919).

CONCLUSION

In a propensity-matched cohort undergoing AF ablation, arrhythmia outcomes assessed by continuous rhythm monitoring did not differ between LB and CB, with an overall low ATAs burden. The only predictor of recurrences was persistent AF. There was no difference in procedure or fluoroscopy time.

Third-generation laser balloon ablation for atrial fibrillation treatment: a multicenter experience

Background

Laser balloon ablation is a promising option for performing pulmonary vein isolation (PVI) which is the cornerstone of invasive atrial fibrillation (AF) treatment.

Purpose

We aimed to investigate the acute efficacy and safety of the novel third-generation of the laser balloon system in an initial multicenter experience.

Methods

First and consecutive patients who underwent PVI with LB3 for drug-resistant paroxysmal or persistent AF at 7 Italian sites were included in this analysis. Study endpoints were acute procedural efficacy, defined as successful isolation of all identified PVs without radiofrequency touch-up, total and fluoroscopy times, and periprocedural complications.

Results

Our population included 86 patients (81% males, mean age 60.6±9.5 years) who underwent a procedure of PVI using LB3 between June 2020 and March 2021.

Most patients had paroxysmal AF (74%) and were in sinus rhythm at the beginning of the procedure. The mean procedure time was 138±60 min; fluoroscopy time was 22±17 min and the mean ablation time was 44±40 min. Of the 313 targeted PVs, 311 (99.4%) could be isolated with first-pass LB3 application, while 2 (0.6%) required radiofrequency touchup. At the end of the procedure, all patients were in sinus rhythm and 26 (32%) received electrical cardioversion to achieve stable sinus rhythm.

The total rate of major compilations was 1.2% (1/82 patients): one pericardial tamponade requiring epicardial puncture. No surgical intervention was necessary, and the patient recovered without any sequalae. There were no vascular access complications or phrenic nervy palsy. Three pinhole balloon raptures (3.5%) were observed during energy applications that required replacement of the whole system but had no effect on patient safety.

Conclusions

In a first multicenter experience, the LB3 system for PVI was safe with excellent acute efficacy.

Funding Acknowledgement

Type of funding sources: None.

Second-generation laser balloon ablation for the treatment of atrial fibrillation assessed by continuous rhythm monitoring: the LIGHT-AF study

AIMS

Balloon-based technologies have been developed to simplify catheter ablation of atrial fibrillation (AF), to improve the clinical outcome of the procedure and to achieve durable pulmonary vein isolation (PVI). The objective of this study is to evaluate the safety and efficacy of second-generation laser balloon (LB2) ablation in the treatment of AF using a continuous cardiac rhythm monitoring strategy. Atrial tachyarrhythmias (ATas) recurrences were assessed with implantable cardiac monitors (ICMs) or devices.

METHODS AND RESULTS

All patients underwent LB2 ablation procedure. The primary endpoint was the first recurrence of any, >5.5 and >24 h duration ATas after the blanking period (90 days). In-hospital visits were performed at 3, 6, and 12 months. Seventy-three patients (68% male, mean age 59.8 ± 11.3) were included in the study. The average procedure, fluoroscopy, and laser ablation times were 81.5 ± 30.1, 21.5 ± 12.4, and 33.8 ± 9.7, respectively. All PVs were isolated using the LB2 with no need of touch-up using focal catheters. No major complications occurred during or after the procedures. The one-year freedom from recurrences was 66.9% (95% CI: 57.0-76.7%), 81.0% (69.5-88.5%), and 86.8% (76.1-92.9%) considering any, 5.5-h and 24-h cut-off duration, respectively. At 3, 6, and 12 months, any ATas was recorded in 22%, 32%, and 25% of patients, with a ≥5% arrhythmic burden documented in 4%, 5%, and 3%, respectively. Few patients reported AF-related symptoms (7%, 8%, and 5%).

CONCLUSION

LB2 ablation is a safe and effective procedure, showing a high freedom from recurrences and low arrhythmic burden as documented by a continuous rhythm monitoring strategy.

Cryoballoon ablation for paroxysmal atrial fibrillation: mid-term outcome evaluated by ECG monitoring with an implantable loop recorder

BACKGROUND

The success rate after cryoballoon ablation (CB-A) performed for paroxysmal atrial fibrillation (PAF) might be overestimated by traditional noninvasive monitoring techniques. The purpose of this study was to evaluate the mid-term outcome of CB-A in patients with PAF implanted with an implantable loop recorder (ILR) after the procedure.

METHODS

Between January 2017 and March 2019, all patients who underwent CB-A for PAF and who were subsequently implanted with an ILR were retrospectively included. All devices were equipped with remote monitoring. All ILR-documented atrial tachycardia (AT) or AF episodes ≥ 6 min were considered as recurrence; both true and false episodes were collected. A 3-month post-procedural blanking period (BP) was applied.

RESULTS

A total of 102 patients (77 men, mean age 60.6 ± 9.6 years) who underwent pulmonary vein isolation (PVI) by CB-A were included; mean time from first diagnosis of AF to PVI was 51.5 ± 46.9 months. Mean follow-up was 29.3 ± 8.1 months; at 12-month follow-up, the success rate was 65.7%, while at 2-year follow-up, freedom from AT/AF recurrences was achieved in 59.3% of the patients. In the follow-up, a total of 4987 ECG strips were analyzed; true-positive episodes were confirmed in 2026 cases (40.6%), whereas 2961 episodes (59.4%) were considered false-positive.

CONCLUSION

In patients with PAF implanted with an ILR, CB-A results in freedom from any AT/AF recurrence in 65.7% of patients at 12-month follow-up and in 59.3% of patients when evaluated at 2-year. Careful adjudication of all ILR-documented AF episodes is required to avoid misdiagnosis.

Outcomes Related to Antiplatelet Therapy in a High-Risk ST-Segment Elevation Myocardial Infarction Population: A Retrospective Real-World Analysis of an Italian ECMO Center

AIM

To evaluate outcomes related to antiplatelet therapy in patients with ST-elevation myocardial infarction (STEMI) admitted to the San Gerardo Hospital in Monza, an extracorporeal membrane oxygenation (ECMO) reference center in the Monza-Brianza area.

METHODS

This retrospective study enrolled patients with STEMI hospitalized between 2013 and 2017.

RESULTS

This study included 653 patients (mean age: 67.5 years, 71% male). Across the study period, ticagrelor use showed consistent increases, from 22% of patients during 2013 to 85% in 2017. Cardiac arrest prehospitalization occurred in 100 patients (15.3%), either at home (n = 85, 13.0%) or during transfer (n = 15, 2.3%); 46 patients underwent ECMO for refractory cardiac arrest. Rates of 90-day survival (hazard ratio [HR]: 2.4, 95% confidence interval [CI]: 1.3-4.4, P = .004) and ST resolution (odds ratio [OR]: 2.5, 95% CI: 1.6-4.1, P = .000) were higher with ticagrelor than with other antiplatelet agents. When analyzed by each agent, patients on ticagrelor had longer survival (HR: 0.4, 95% CI: 0.2-0.8, P = .008) than patients on clopidogrel and more frequent ST resolution than those on clopidogrel or prasugrel (OR: 0.4, 95% CI: 0.2-0.7, P = .002 and OR: 0.4, 95% CI: 0.2-0.7, P = .006). There was no difference in mortality between ticagrelor and prasugrel.

CONCLUSIONS

Changes in the treatment of high-risk patients with STEMI over time are in line with changes in treatment guidelines. In these patients, ticagrelor is associated with significantly improved 90-day mortality compared with clopidogrel.

Effects of prostaglandin E1alpha cyclodextrin [corrected] treatment on endothelial dysfunction in patients with systemic sclerosis

OBJECTIVE

Systemic sclerosis (SSc) is characterized by an altered nitric oxide (NO): endothelin I ratio and by endothelial dysfunction.

AIMS

To verify the effects of prostaglandin E1 (PGE1) alpha-cyclodestrin treatment on endothelial function, quantified as flow-mediated dilation (FMD) of the radial artery.

METHODS

In 16 women with SSc (age 57 +/- 2.7 years, means +/- SE) in whom a diagnosis of SSc had been made several years earlier (7.1 +/- 1.2 years), FMD was evaluated by an echotracking technique on the radial artery, using trinitroglycerin vasodilation as a non-endothelial measure of the vessel's ability to increase its diameter maximally. FMD was evaluated after 4 months washout period and after 4 months cyclic infusion of PGE1 alpha-cyclodestrin. Expired NO was measured at the same time.

RESULTS

PGE1 alpha-cyclodestrin cyclic infusions did not modify systolic and diastolic blood pressure, heart rate or trinitroglycerin radial artery vasodilation. On the other hand, it induced a marked and significant increase in FMD of the radial artery, which was also accompanied by an increase in blood flow and expired NO.

CONCLUSIONS

Endothelial dysfunction and reduced FMD associated with SSc are improved by cyclic treatment with PGE1 alpha-cyclodestrin. This effect occurs together with a concomitant increase in expired NO, suggesting its direct positive influence on endothelial function. It may also partly explain the clinical beneficial effect of the drug in SSc.