Left atrial appendage occlusion versus standard of care in patients with atrial fibrillation and a prior thrombo-embolic event despite oral anticoagulant therapy: a propensity score matched comparison

Introduction

Patients with atrial fibrillation (AF) that suffer from ischemic stroke despite oral anticoagulant (OAC) therapy have a very high risk of recurrent stroke and better prevention strategies are needed. Left atrial appendage occlusion (LAAO) is a promising secondary prevention strategy that may provide mechanical protection in patients that suffer from thrombo-embolic events under OAC. However, evidence showing effectiveness of LAAO in this population is scarce and the current international guidelines only consider LAAO in patients with a contra-indication for OAC.

Purpose

To compare percutaneous LAAO to standard-of-care including continuing/switching anticoagulation therapy for secondary stroke prevention in patients with AF and a prior thrombo-embolic event and/or LAA thrombus under OAC therapy.

Methods

The STR-OAC LAAO cohort is an international collaboration combining a selection of patients from multiple LAAO registries (22 participating centers). Patients that underwent percutaneous LAAO because of a thrombo-embolic event and/or LAA thrombus on OAC were included. Propensity score matching (optimal matching method, 1:1 ratio) with a previously published multi-center dataset of patients continuing/switching anticoagulation treatment after a thrombo-embolic event was performed to adjust for imbalances in age, sex, hypertension, diabetes mellitus and CHA2DS2-VASc score. The primary outcome was ischemic stroke. Time-to-event analysis was performed with Kaplan-Meier curves and Cox-proportional-hazard regression analyses.

Results

A total of 404 patients underwent LAAO between 2010–2021 and were included in the STR-OAC LAAO cohort. Mean age was 72±9 years; 44% was female and mean CHA2DS2-VASc and HAS-BLED score were 4.8±1.7 and 2.5±1.4, respectively. Most patients received a Watchman or Amplatzer device (53% and 43%). Oral anticoagulation was discontinued after LAAO at discharge or after confirmation of adequate LAA closure at 1–3 months follow-up in 44% or 20%, respectively. The remaining 35% of patients continued OAC after LAAO as an adjunctive strategy. All LAAO patients were propensity-score matched and included in the primary outcome analysis. Baseline characteristics were well balanced after matching (Table 1). During follow up including 1406 patient-years (LAAO 1007; control 399) a total of 61 patients experienced an ischemic stroke: 2.2% per patient-year in LAAO group versus 9.8% per patient-year in the control group. LAAO was associated with a significantly lower risk of ischemic stroke (HR 0.33, 95% CI [0.19–0.59], p<0.001) compared to standard-of-care (Figure 1).

Conclusion

In this propensity-score matched study, LAAO was associated with a lower risk of ischemic stroke compared to standard-of-care in patients with a thrombo-embolic event and/or LAA thrombus despite OAC treatment. Randomized controlled trial data may further confirm the effectiveness of LAAO in this very high-risk population.

Funding Acknowledgement

Type of funding sources: None.

Evaluating long-term outcomes of left atrial appendage occlusion: the results of a prospective single-center registry

Funding Acknowledgements

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): This work was supported by an unrestricted grant from Boston Scientific. Boston Scientific was not involved in the design/conduct of the study, data collection/analysis and interpretation of the data and preparation of the manuscript.

Background

Percutaneous left atrial appendage occlusion is an emerging alternative to anticoagulation in the prevention for stroke in patients with atrial fibrillation, especially in patients with a contra-indication for oral anticoagulation therapy. Long-term results on the efficacy and safety of this treatment remain scarce.

Methods

In this single-center prospective registry, data of all consecutive patients that underwent percutaneous left atrial appendage closure between 2009 and 2019 were collected. Patients with successful left atrial appendage closure (peri-device leakage ≤5mm) and at least one year of follow-up data were analyzed. The occurrence of thrombo-embolic events (ischemic stroke, TIA and systemic embolism), major bleeding events (BARC >2) and anticoagulation use during long-term follow-up were evaluated.

Results

A total of 192 patients after left atrial appendage occlusion were included (61 % male, age 69.0 ± 8.4 years, CHA2DS2-VASc 4.0[3.0-5.0], HAS-BLED 3.0[2.0-3.25]) with a mean follow-up duration of 5.7 ± 2.8 years (in total 1087 patient-years). During follow-up 36 patients (19%) died. 49 thrombo-embolic complications were observed in 38 patients. The ischemic stroke rate was 1.9 events per 100 patient-years, accounting for a 70% reduction compared to CHA2DS2-VASc predicted rate. Device-related thrombus (DRT) occurred in 5 patients (2.6%), 3 were observed during routine follow-up and were not associated with thrombo-embolic complications. The other 2 DRT were observed in patients presenting with ischemic stroke more than 3 years after device implantation. Furthermore, 38 non-procedural major bleeding complications occurred in 19 patients, resulting in 3.5 events per 100-patients years, accounting for a reduction of 43% compared to estimated bleeding rates under OAC use. At the end of the study 71% of all patients were on single antiplatelet or no antiplatelet/anticoagulation treatment at all.

Conclusions

During long-term follow-up thrombo-embolic event rates and non-procedural major bleeding rates were consistently low (ischemic stroke rate reduction 70% and non-procedural major bleeding rate reduction 40% compared to predicted rates). These results confirm the efficacy of left atrial appendage occlusion. Abstract Figure. Ischemic stroke rates

Long-term monitoring of arrhythmias in cardiac sarcoidosis

Introduction

Screening for cardiac sarcoidosis (CS) is recommended since it can manifest with ventricular arrhythmias (VA), atrioventricular conduction block (AVB) and sudden cardiac death (SCD). However, risk stratification for SCD is challenging, in particular in patients without overt cardiac symptoms.

Purpose

This study reports the practice-based risk stratification for SCD and the incidence of arrhythmias and mortality in CS patients by long-term monitoring of arrhythmias.

Methods

A retrospective, single center cohort study was performed in 537 patients with sarcoidosis screened for cardiac involvement with cardiac MRI and fluorodeoxyglucose PET in an hospital, a Dutch tertiary referral center. CS was diagnosed in 115 of 537 patients (21%), complete follow up was available in 108 patients (94%). After risk assessment for SCD (figure 1) an ICD was implanted in 16 high-risk patients. Within the92 low-risk patients, 80 had an internal loop recorder (ILR) implanted and 12 patients received no device. Chart review was performed to assess the occurrence of VA, AVB, death, ICD therapy and device related complications.

Results

During a mean follow-up of 31±15 months, 9 out of 80 ILR patients (11.3%) received an ICD of whom 7 (8.8%) based on recorded arrhythmias (VA in 5 and AVB in 2 patients).

Five out of the total 25 ICD patients (20%) experienced sustained VA successfully treated with anti-tachycardia pacing in 2 (8%) and terminated spontaneously in all other patients. Two ICD patients experienced a mild pocket infection, treated with antibiotics. Two deaths occurred in the low-risk patients: 1 non-cardiac death and 1 SCD due to asystole.

Conclusion

The practice-based risk stratification supported an ICD implantation in up to 5% of sarcoidosis patients screened for CS. Sustained VA occurred in 20% of ICD patients.Early detection of important arrhythmias with an ILR can optimize risk assessment for SCD in CS.

Practise-based risk stratification

Funding Acknowledgement

Type of funding source: None