Left atrial appendage closure device implantation in patients at very high risk for stroke

Lower rate of major bleeding in very high risk patients undergoing left atrial appendage occlusion: A propensity score-matched comparison with direct oral anticoagulant

BACKGROUND

Long-term oral anticoagulation is the mainstay therapy for thromboembolic (TE) prevention in patients with atrial fibrillation. However, left atrial appendage occlusion (LAAO) could be a safe alternative to direct oral anticoagulants (DOACs) in patients with a very high TE risk profile.

OBJECTIVE

The purpose of this study was to compare the safety and efficacy of LAAO vs DOACs in patients with atrial fibrillation at very high stroke risk (CHA2DS2-VASc [congestive heart failure, hypertension, age ≥ 75 years, diabetes mellitus, prior stroke or transient ischemic attack or thromboembolism, vascular disease, age 65-74 years, sex category] score ≥ 5).

METHODS

Data from patients with CHA2DS2-VASc score ≥ 5 were extracted from a prospective multicenter database. To attenuate the imbalance in covariates between groups, propensity score matching was used (covariates: CHA2DS2-VASc and HAS-BLED [hypertension, abnormal renal or liver function, stroke, bleeding, labile international normalized ratio, elderly, drugs or alcohol] scores), which resulted in a matched population of 277 patients per group. The primary end point was a composite of cardiovascular death, TE events, and clinically relevant bleeding during follow-up.

RESULTS

Of 2381 patients, 554 very high risk patients were included in the study (mean age 79 ± 7 years; CHA2DS2-VASc score 5.8 ± 0.9; HAS-BLED score 3.0 ± 0.9). The mean follow-up duration was 25 ± 11 months. A higher incidence of the composite end point was documented with DOACs compared with LAAO (14.9 events per 100 patient-years in the DOAC group vs 9.4 events per 100 patient-years in the LAAO group; P = .03). The annualized clinically relevant bleeding risk was higher with DOACs (6.3% vs 3.2%; P = .04), while the risk of TE events was not different between groups (4.1% vs 3.2%; P = .63).

CONCLUSION

In high-risk patients, LAAO had a similar stroke prevention efficacy but a significantly lower risk of clinically relevant bleeding when compared with DOACs. The clinical benefit of LAAO became significant after 18 months of follow-up.

Residual Stroke Risk in Atrial Fibrillation

AF contributes to increased stroke risk via various mechanisms, including deranged blood constituents, vessel wall abnormalities and abnormal blood flow. This excess risk is frequently managed with anticoagulation therapy, aimed at preventing thromboembolic complications. Yet, a significant proportion of patients with AF remain at high residual stroke risk despite receiving appropriate dose-adjusted anticoagulation. This article explores the residual stroke risk in AF and potential therapeutic options for these patients.

Long-Term Effect of Left Atrial Appendage Occlusion in Treating Patients with Previous Ischemic Stroke on the Disease Recurrence

Methods

A total of 120 patients with IS admitted to Tangdu Hospital from July 2016 to September 2017 were grouped into the control group (n = 60) and the observation group (n = 60). Patients in the control group were only treated with thrombolytics and anticoagulants while those in the observation group were treated with both drugs and LAAO. Transesophageal echocardiography (TEE) was performed to observe the occlusion of LAA in patients in the observation group after 45 d and 6 months, respectively. Clinical outcomes in two groups were compared from the following aspects: recurrence of IS, incidence of systemic embolism, and the 3-year recurrence-free survival (RFS). The 3-year IS recurrence of patients was compared by Fisher's exact test.

Results

No significant differences were observed at baseline levels (age, sex, etc.) between the observation group and control group (p > 0.05). During follow-up visit of 45 d and 6 months, all occluders met the efficacious occludsion criteria. The results of TEE at 45 d after LAAO showed that 50% of patients (30/60) in the observation group had complete occlusion of LAA. The results of TEE at 6 months after LAAO suggested that 58.3% of patients (35/60) had complete occlusion of LAA. IS recurrence in the observation group (3.33%, 2/60) was significantly lower than that in the control group (18.33%, 11/60), with the difference presenting statistical significance (p = 0.008). Incidence of systemic embolism in the observation group (1.67%, 1/60) was markedly lower than that in the control group (13.33%, 11/60) (p = 0.014). The average RFS in the observation group (31.97 months, 95% CI: 27.50~32.31 months) was notably longer than that in the control group (29.91 months, 95% CI: 29.85~32.92 months) (p < 0.05). The 3-year IS recurrence of patients between two groups compared by Fisher's exact test showed significant differences (1 year: p = 0.014, 2 year: p = 0.008, 3 year: p = 0.008).

Conclusion

Regarding patients with previous IS who had poor response to thrombolytics and anticoagulants, LAAO could effectively decrease recurrence of IS and incidence of systemic embolism and prolong RFS of patients. LAAO was, therefore, an alternative for patients with high IS recurrence risk.

The Watchman device for preventing stroke in patients with atrial fibrillation

ABSTRACT

Atrial fibrillation (AF) is one of the most common sustained dysrhythmias that increases in prevalence with age, and is associated with strokes that can lead to significant patient morbidity and mortality. AF prevalence is projected to double over the next 25 years, demonstrating the need for innovative and effective stroke prevention modalities. Two options are direct oral anticoagulants and left atrial appendage occlusion. This article discusses the Watchman device, a left atrial appendage occlusion device that provides an option for patients with contraindications for anticoagulation.

Recurrent embolisms despite adequate anticoagulant therapy in a patient with prosthetic heart valves and atrial fibrillation: a case report

BACKGROUND

Antithrombotic management in patients with atrial fibrillation (AF) that have undergone heart valve surgery may be challenging, especially in the context of thromboembolic events during follow-up. The combination of pharmacological therapies with modern transcatheter interventions allows these more complex cases to be overcome.

CASE SUMMARY

We present the case of a 66-year-old female with a history of AF and mechanical aortic and mitral valve replacement, which was admitted to the hospital complaining of dizziness and unsteady gait. A computerized tomography scan of the brain confirmed the diagnosis of embolic stroke. Two years later, the patient complained of sudden onset of chest pain, accompanied by electrocardiographic abnormalities and elevated high-sensitivity troponin T. Emergency cardiac catheterization revealed embolic myocardial infarction with distal occlusion of the obtuse marginal artery. Again, 2 years later, the patient suffered a new cerebral embolic event. Given the adequate anticoagulation therapy throughout almost the entire clinical course, percutaneous left atrial appendage closure was proposed as an adjunct to vitamin K antagonist treatment. Notably, intraprocedural transoesophageal echocardiography revealed the presence of a previously undetected left atrial appendage thrombus, thus an embolic protection device was used during the procedure, which was successfully carried out without complications.

DISCUSSION

This case report demonstrates the complexity of the antithrombotic management in patients with AF and prosthetic heart valves, and highlights the importance of an individualized approach, integrating new therapeutic strategies to achieve success, in patients that present thromboembolic events despite adequate anticoagulation therapy.

Indications and Outcome in Patients Undergoing Left Atrial Appendage Closure-The Austrian LAAC Registry

Background: Complete real-world data on the indications and outcomes of left atrial appendage closure (LAAC) outside of clinical trials are rare. In this study, we stratified patients undergoing LAAC by indication groups. Methods: This analysis of the national multicentre Austrian LAAC Registry comprised all patients that underwent LAAC up until 2018 at the currently active centres in Austria. The baseline characteristics, procedural details and outcomes between the following indication groups were compared: bleeding as an indication for LAAC (“bleeding” group) vs. thromboembolism despite oral anticoagulation (OAC; “thromboembolism” group) vs. an intolerance to OAC for reasons other than the above (“other” group). Results: The analysis included 186 patients, with 59.7% in the “bleeding” group, 8.1% in the “thromboembolism” group and 32.2% in the “other” group. The CHADS₂ score was the highest in the “thromboembolism” group and the HAS-BLED score was the highest in the “bleeding” group. The procedural outcomes were similar between groups (implantation success, 97.3%), with major complications occurring in 7.0% of patients. One-year survival free from stroke, bleeding or LAAC-associated hospitalisation was 83.9%, 90.0% and 81.4% in the “bleeding”, “thromboembolism” and “other” groups, respectively (p = 0.891). Conclusions: In routine clinical practice, LAAC was used in a heterogeneous patient population with atrial fibrillation (AF) and contraindication, inefficacy or intolerance to OAC. The long-term outcome was favourable in all groups.

Comparison Between Oral Anticoagulation and Left Atrial Appendage Occlusion in the Prevention of Stroke With Regard to Non-Valvular Atrial Fibrillation

In the past, the most common type of atrial fibrillation leading to stroke was valvular; this was predominantly due to the prevalence of rheumatic fever, but with the advent of better-hospitalized care, the cases of valvular atrial fibrillation declined. In recent years, there has been an increase in cases of stroke due to non-valvular atrial fibrillation. Stasis of blood in the left atrial pouch leads to coagulation and thrombi formation, which may lead to stroke. Oral medication or mechanical intervention can prevent thrombi formation. Both oral anticoagulation and left atrial appendage occlusion (LAAO) have been compared to see which has better outcomes. It was observed that LAAO has greater efficacy, but with time throughout a couple of years, no considerable difference was seen when compared to warfarin. Most of the long-term randomized controlled trials have been performed with the Watchman^® device. Although the Lariat and Amplatzer LAAO devices have also shown favorable outcomes, there is still a deficiency when it comes to trials of high-quality evidence using these devices as an intervention. Dual therapy with both of these approaches showed a decline in the count of major bleeding episodes on follow-up. Overall, albeit both methods have proven useful, LAAO has a slight advantage in efficacy and leads to less hemorrhagic events.