The ALSTER-FLX Registry: 3-month outcomes following left atrial appendage occlusion employing a next-generation device, a matched-pair-analysis to EWOLUTION

Left Atrial Appendage Closure: A Narrative Review

Atrial fibrillation (AF) is the most common cardiac arrhythmia and the cause of thromboembolic events in elderly patients worldwide. AF is associated with a significantly increased risk of morbidity and mortality due to cardiac emboli, primarily from left atrial appendage (LAA) thrombus. Oral anticoagulation therapy is the standard treatment to effectively reduce the risk of thromboembolic events in patients with AF. However, anticoagulation treatment increases bleeding risk. LAA closure (LAAC) has recently been introduced as a feasible mechanical preventive intervention for thromboembolic events while minimizing the risk of bleeding. Transcatheter LAAC devices have evolved in the past decade, and several ongoing trials have demonstrated the improvements of safety and outcomes in newer generation devices. This review summarizes the current perspectives and outcomes regarding LAAC as an alternative to pharmacologic therapy.

Limitations in Contemporary Pharmacological Stroke Prevention Therapies in Atrial Fibrillation: A Descriptive Literature Review

The most common arrhythmia, atrial fibrillation (AF), increases with age and is associated with a 5-fold increased risk of stroke. Although lifelong oral anticoagulation (OAC) is strongly recommended for stroke prevention in patients with AF and CHA2DS2-VASc ≥ 2 only 50-60% of patients in Western countries belonging to this group are treated with oral anticoagulants, and less than half of these adhere to therapy over time. Before 2010, the numerous limitations associated with vitamin K antagonists (VKAs) were considered to be the reason behind OAC underuse; however, the approval of direct oral anticoagulants (DOACs) that require once- or twice-daily intake, no regular blood tests and fewer drug-food interactions has resulted in only modest improvements in OAC use and adherence.

Rationale and design of a randomized study comparing the Watchman FLX device to DOACs in patients with atrial fibrillation

BACKGROUND

Percutaneous left atrial appendage (LAA) closure (LAAC) was developed as a nonpharmacologic alternative to oral anticoagulants (OACs) in patients with atrial fibrillation (AF) who are at an increased risk for stroke or systemic embolism. The Watchman device permanently seals off the LAA to prevent thrombi from escaping into the circulation. Previous randomized trials have established the safety and efficacy of LAAC compared to warfarin. However, direct OACs (DOACs) have become the preferred pharmacologic strategy for stroke prevention in patients with AF, and there is limited data comparing Watchman FLX to DOACs in a broad AF patient population. CHAMPION-AF is designed to prospectively determine whether LAAC with Watchman FLX is a reasonable first-line alternative to DOACs in patients with AF who are indicated for OAC therapy.

STUDY DESIGN

A total of 3,000 patients with a CHA2DS2-VASc score ≥2 (men) or ≥3 (women) were randomized to Watchman FLX or DOAC in a 1:1 allocation at 142 global clinical sites. Patients in the device arm were to be treated with DOAC and aspirin, DOAC alone, or DAPT for at least 3 months postimplant followed by aspirin or P2Y12 inhibitor for 1-year. Control patients were required to take an approved DOAC for the duration of the trial. Clinical follow-up visits are scheduled at 3- and 12-months, and then annually through 5 years; LAA imaging is required at 4 months in the device group. Two primary end points will be evaluated at 3 years: (1) composite of stroke (ischemic/hemorrhagic), cardiovascular death, and systemic embolism compared for noninferiority, and (2) nonprocedural bleeding (International Society on Thrombosis and Haemostasis [ISTH] major and clinically relevant nonmajor bleeding) tested for superiority in the device arm against DOACs. The third primary noninferiority end point is the composite of ischemic stroke and systemic embolism at 5 years. Secondary end points include 3- and 5-year rates of (1) ISTH-defined major bleeding and (2) the composite of cardiovascular death, all stroke, systemic embolism, and nonprocedural ISTH bleeding.

CONCLUSIONS

This study will prospectively evaluate whether LAAC with the Watchman FLX device is a reasonable alternative to DOACs in patients with AF.

CLINICAL TRIAL REGISTRATION

NCT04394546.

Diabetes mellitus and atrial fibrillation-from pathophysiology to treatment

Type 2 diabetes mellitus (T2DM) is a leading risk factor for cardiovascular complications around the globe and one of the most common medical conditions. Atrial fibrillation (AF) is the most common supraventricular arrhythmia, with a rapidly increasing prevalence. T2DM has been closely associated with the risk of AF development, identified as an independent risk factor. Regarding cardio-vascular complications, both AF and T2DM have been linked with high mortality. The underlying pathophysiology has not been fully determined yet; however, it is multifactorial, including structural, electrical, and autonomic pathways. Novel therapies include pharmaceutical agents in sodium-glucose cotransporter-2 inhibitors, as well as antiarrhythmic strategies, such as cardioversion and ablation. Of interest, glucose-lowering therapies may affect the prevalence of AF. This review presents the current evidence regarding the connection between the two entities, the pathophysiological pathways that link them, and the therapeutic options that exist.

Clinical efficacy and safety comparison of Watchman device versus ACP/Amulet device for percutaneous left atrial appendage closure in patients with nonvalvular atrial fibrillation: A study-level meta-analysis of clinical trials

Left atrial appendage occlusion is not inferior to oral anticoagulants in the prevention of stroke in several randomized controlled trials. However, the clinical efficacy and safety comparison of the Watchman and amplatzer cardiac plug (ACP)/Amulet devices for percutaneous left atrial appendage closure (LAAC) in patients with non-valvular atrial fibrillation was controversial. A database search was conducted using PubMed, EMBASE, Cochrane Library, and Clinicaltrials.gov for trials that compared Watchman device vs ACP/Amulet device. The effective outcomes were stroke and systemic embolism. Safety outcomes were all-cause death, cardiovascular death, and major bleeding. Device-related complications included device-related thrombus (DRT), peri-device leaks (PDL > 5 mm). A total of 19 articles involving 6224 patients were included in the present study. The Watchman and ACP/Amulet groups comprised 3267 and 2957 patients, respectively. No statistically significant differences were detected in the stroke (odd ratio [OR]:1.24, 95% confidence interval [CI]: 0.92-1.67, p = .17, I²  = 0), systemic embolism (OR:1.10, 95% CI: 0.51-2.35, p = .81, I²  = 0%), all-cause death (OR:0.97, 95% CI: 0.80-1.18, p = .77, I²  = 1%), cardiogenic death (OR:0.99, 95% CI: 0.77-1.29, p = .96, I²  = 0%), major bleeding (OR:1.18, 95% CI: 0.98-1.43, p = .08, I²  = 25%). DRT (OR:1.48, 95% CI: 1.06-2.06, p = .02, I²  = 0%) and PDL > 5 mm (OR:2.57, 95% CI: 1.63-4.04, p < .0001, I²  = 0%) were significantly lower in ACP/Amulet group compared to Watchman group. The effective and safety outcomes were comparable between two groups. ACP/Amulet group had significantly lower rates of DRT and PDL > 5 mm than Watchman group.

Comparison of outcomes between novel oral anticoagulants and warfarin monotherapy in patients with left atrial appendage closure: A systematic review and meta-analysis

Background

Pivotal trials of percutaneous left atrial appendage closure (LAAC) used dedicated post-procedure antithrombotic protocols. However, there is no consensus on the selection of new oral anticoagulants (NOAC) and warfarin monotherapy after LAAC. This study aims to compare NOAC with warfarin monotherapy for efficacy and safety in patients undergoing LAAC.

Methods

A database search was conducted using PubMed, EMBASE, Cochrane Library, and Clinicaltrials.gov for trials that compared NOAC with warfarin monotherapy after LAAC. The effective outcomes included any major adverse events (all-cause death, stroke, major bleeding) and their individual components. Safety outcomes included all-cause death, major bleeding, total bleeding, DRT, and PDL >5 mm.

Results

We included 10 non-randomized clinical trials with 10,337 patients, of whom 4,960 patients received NOAC, while 5,377 patients received warfarin. There were no statistically significant differences in any major adverse events (LogOR: −0.11, 95% CI: −0.27, 0.04, P = 0.16), stroke (LogOR: 0.00, 95% CI: −0.42, 0.42, P = 1.00), all-cause death (LogOR: −0.23, 95% CI: −0.48, 0.02, P = 0.07), major bleeding (LogOR: −0.22, 95% CI: −0.45, 0.01, P = 0.06). NOAC was associated with a significant reduction in total bleeding (LogOR: −1.01, 95% CI: −1.47, −0.55, P < 0.0001) compared to warfarin. No statistically significant differences were found in DRT (LogOR: −0.19, 95% CI: −0.15, 0.52, P = 0.27) and PDL >5 mm (LogOR: 0.19, 95% CI: −0.33, 0.72, P = 0.47). Meta-regression and subgroup analysis showed that total bleeding (LogOR: −1.56, 95% CI: −2.15, −0.97, P < 0.001) was significantly lower in the NOAC group in the subgroup of <75 y.

Conclusion

After LAAC, NOAC monotherapy was associated with a lower risk of bleeding compared to warfarin monotherapy for 45 days. There was no significant difference between NOAC and warfarin in terms of other results.

Systematic review registration

www.york.ac.uk/inst/crd, identifier: CRD42022361244.

Percutaneous Treatment Approaches in Atrial Fibrillation: Current Landscape and Future Perspectives

Atrial fibrillation (AF), the most common sustained arrhythmia in clinical practice, represents a major cause of morbidity and mortality, with an increasing prevalence. Pharmacologic treatment remains the cornerstone of its management through rhythm and rate control, as well as the prevention of thromboembolism with the use of oral anticoagulants. Recent progress in percutaneous interventional approaches have provided additional options in the therapeutic arsenal, however. The use of the different catheter ablation techniques can now lead to long arrhythmia-free intervals and significantly lower AF burden, thus reducing the rate of its complications. Particularly encouraging evidence is now available for patients with persistent AF or concomitant heart failure, situations in which catheter ablation could even be a first-line option. In the field of stroke prevention, targeting the left atrial appendage with percutaneous device implantation may reduce the risk of thromboembolism to lower rates than that predicted with conventional ischemic risk scores. Left atrial appendage occlusion through the approved Watchman or Amplatzer devices is a well-established, efficacious, and safe method, especially in high-ischemic and bleeding risk patients with contraindications for oral anticoagulation.