Prior Anticoagulation and Short- or Long-Term Clinical Outcomes in Ischemic Stroke or Transient Ischemic Attack Patients With Nonvalvular Atrial Fibrillation

Left atrial appendage closure in patients with atrial fibrillation and acute ischaemic stroke despite anticoagulation

BACKGROUND

The occurrence of acute ischaemic stroke (AIS) while using oral anticoagulants (OAC) is an increasingly recognised problem among nonvalvular atrial fibrillation (NVAF) patients. We aimed to elucidate the potential role of left atrial appendage closure (LAAC) for stroke prevention in patients with AIS despite OAC use (AIS-despite-OAC).

METHODS

We retrospectively collected baseline and follow-up data from consecutive NVAF patients who had AIS-despite-OAC and subsequently underwent endovascular LAAC, between January 2015 and October 2021. The primary outcome measure was the occurrence of AIS after LAAC, and the safety outcome was symptomatic intracerebral haemorrhage (ICH).

RESULTS

29 patients had LAAC specifically because of AIS-despite-OAC. The mean age at the time of the procedure was 73.4±8.7, 13 were female (44.82%). The mean CHA2DS2-VASc score was 5.96±1.32, with an expected AIS risk of 8.44 per 100 patient-years. 14 patients (48%) had two or more past AIS-despite-OAC. After LAAC, 27 patients (93.10%) were discharged on OAC which was discontinued in 17 (58.62%) after transoesophageal echocardiogram at 6 weeks. Over a mean of 1.75±1.0 years follow-up after LAAC, one patient had an AIS (incidence rate (IR) 1.97 per 100 patient-years). One patient with severe cerebral microangiopathy had a small ICH while on direct OAC and antiplatelet 647 days after LAAC.

CONCLUSIONS

LAAC in AIS-despite-OAC patients demonstrated a low annual AIS recurrence rate in our cohort (1.97%) compared with the expected IR based on their CHA2DS2-VASc scores (8.44%) and to recent large series of AIS-despite-OAC patients treated with OAC/aspirin only (5.3%-8.9%). These hypothesis-generating findings support randomised trials of LAAC in AIS-despite-OAC patients.

Contemporary outcomes of acute ischemic stroke in atrial fibrillation patients on anticoagulation

BACKGROUND

Long-term anticoagulation (AC) therapy reduces the risk of stroke in patients with Atrial Fibrillation (AF). However, data on the impact of AC on in-hospital stroke outcomes is lacking.

METHODS

The National Inpatient Sample was used to identify adult inpatients with AF and a primary diagnosis of ischemic stroke between 2016 and 2020. Data was stratified between AC users and nonusers. A multivariate regression model was used to describe the in-hospital outcomes, adjusting for significant comorbidities.

RESULTS

A total of 655,540 hospitalizations with AF and a primary hospitalization diagnosis of ischemic stroke were included, of which 194,560 (29.7 %) were on long-term AC. Patients on AC tended to be younger (mean age, 77 vs. 78), had a higher average CHA2DS2VASc score (4.48 vs. 4.20), higher rates of hypertension (91 % vs. 88 %), hyperlipidemia (64 % vs. 59 %), and heart failure (34 % vs. 30 %) compared to patients not on long-term AC. Use of AC was associated with decreased in-hospital mortality (aOR [95 % CI]: 0.62 [0.60-0.63]), decreased stroke severity (mean NIHSS, 8 vs. 10), decreased use of tPA (aOR 0.42 [0.41-0.43]), mechanical thrombectomy (aOR 0.85 [0.83-0.87]), intracranial hemorrhage (aOR 0.69 [0.67-0.70]), gastrointestinal bleeding (aOR 0.74 [0.70-0.77]), and discharge to skilled nursing facilities (aOR 0.90 [0.89-0.91]), compared to patients not on AC (P<0.001 for all comparisons).

CONCLUSION

Among patients with AF admitted for acute ischemic stroke, AC use prior to stroke was associated with decreased in-hospital mortality, decreased stroke severity, decreased discharge to SNF, and fewer stroke-related and bleeding complications.

Atrial Fibrillation and Reperfusion Therapy in Acute Ischaemic Stroke Patients: Prevalence and Outcomes-A Comprehensive Systematic Review and Meta-Analysis

Atrial fibrillation (AF) significantly contributes to acute ischaemic stroke (AIS), yet its precise influence on clinical outcomes post-intravenous thrombolysis (IVT) and post-endovascular thrombectomy (EVT) has remained elusive. Furthermore, the overall prevalence of AF in AIS patients undergoing reperfusion therapy has not been clearly determined. Employing random-effects meta-analyses, this research aimed to estimate the pooled prevalence of AF among AIS patients undergoing reperfusion therapy, while also examining the association between AF and clinical outcomes such as functional outcomes, symptomatic intracerebral haemorrhage (sICH) and mortality. Studies comparing AF and non-AF patient groups undergoing reperfusion therapy were identified and included following an extensive database search. Forty-nine studies (n = 66,887) were included. Among IVT patients, the prevalence of AF was 31% (Effect Size [ES] 0.31 [95%CI 0.28-0.35], p < 0.01), while in EVT patients, it reached 42% (ES 0.42 [95%CI 0.38-0.46], p < 0.01), and in bridging therapy (BT) patients, it stood at 36% (ES 0.36 [95%CI 0.28-0.43], p < 0.01). AF was associated with significantly lower odds of favourable 90-day functional outcomes post IVT (Odds Ratio [OR] 0.512 [95%CI 0.376-0.696], p < 0.001), but not post EVT (OR 0.826 [95%CI 0.651-1.049], p = 0.117). Our comprehensive meta-analysis highlights the varying prevalence of AF among different reperfusion therapies and its differential impact on patient outcomes. The highest pooled prevalence of AF was observed in EVT patients, followed by BT and IVT patients. Interestingly, our analysis revealed that AF was significantly associated with poorer clinical outcomes following IVT. Such an association was not observed following EVT.

Association Between Inappropriately Dosed Anticoagulation Therapy With Stroke Severity and Outcomes in Patients With Atrial Fibrillation

Background

Oral anticoagulation (OAC) is effective for stroke prevention in patients with atrial fibrillation. However, some patients experience stroke despite OAC therapy, and knowledge about the impact of prior treatment quality is lacking.

Methods and Results

Patients with atrial fibrillation on OAC therapy who had a first‐time ischemic stroke were identified in the Danish Stroke Registry (2005–2018). Patients treated with vitamin K antagonist (VKA) therapy were compared according to the international normalized ratio just before stroke (international normalized ratio <2 [subtherapeutic], international normalized ratio 2–3 [therapeutic], international normalized ratio >3 [supratherapeutic]), and patients on underdosed, appropriately dosed, and overdosed direct OAC (DOAC) therapy were compared. Stroke severity was determined using the Scandinavia Stroke Scale (0–58 points), and the risk of very severe stroke (0–14 points) was analyzed by multivariable logistic regression. One‐year mortality was determined using multivariable Cox regression. A total of 2319 patients with atrial fibrillation and stroke were included; 1196 were taking a VKA (subtherapeutic [46%], therapeutic [43%], supratherapeutic [11%]), and 1123 were taking DOAC (underdosed [23%], appropriately dosed [60%], and overdosed [17%]). Subtherapeutic and supratherapeutic VKA therapy (compared with therapeutic) and underdosed DOAC therapy (compared with appropriate and underdosed DOAC) patients were older, more often women, and more comorbid. Subtherapeutic VKA therapy was associated with very severe stroke (odds ratio [OR], 2.06 [95% CI, 1.28–3.31]), whereas supratherapeutic VKA therapy was not (OR, 1.24 [95% CI, 0.60–2.57]) compared with therapeutic VKA therapy. Patients on subtherapeutic and supratherapeutic VKA therapy had a higher 1‐year mortality (hazard ratio [HR], 1.66 [95% CI, 1.29–2.13]); HR, 1.55 [95% CI, 1.08–2.22], respectively) than those on therapeutic VKA therapy. Treatment with underdosed or overdosed DOAC therapy was not associated with very severe stroke (OR, 1.27 [95% CI, 0.76–2.15]; OR, 0.73 [95% CI, 0.37–1.43], respectively) and was not associated with 1‐year mortality (HR, 1.09 [95% CI, 0.83–1.44]; HR, 0.82 [95% CI, 0.57–1.18], respectively) than appropriate DOAC.

Conclusions

Half of the patients with atrial fibrillation with stroke were on inappropriate OAC therapy. Subtherapeutic VKA was associated with worse stroke severity and higher mortality rate than therapeutic VKA therapy. Neither underdosed nor overdosed DOAC was associated with worse outcomes in adjusted models compared with appropriately dosed DOAC. This study supports DOAC as a first‐line therapy over VKA.

Ischemic stroke in oral anticoagulated patients with atrial fibrillation

BACKGROUND

Ischemic strokes in orally anticoagulated patients pose challenges for acute management and secondary prevention but the characteristics of these strokes are poorly understood. We examined the clinical and imaging features, the presumed underlying etiology and the subsequent antithrombotic management.

METHODS

We analyzed a consecutive series of patients enrolled into the EIDASAF study, a single center, observational study of ischemic stroke patients with a diagnosis atrial fibrillation (AF) prior to the index event who had been admitted to the Hyperacute Stroke Unit of Imperial College London between 2010 and 2017. We compared patients with oral anticoagulation therapy prior admission (OAC_prior ) with those without anticoagulation (OAC_naive ). Brain imaging was analyzed centrally.

RESULTS

763 patients were included in the analysis. 481 (63%) were OAC_naive while 282 (37%) were OAC_prior . Patients with OAC_prior were younger, more often had a previous history of stroke or transient ischemic attack (TIA), and more often suffered from hypertension and diabetes. In OAC_naive, patients, large and deep middle cerebral artery infarcts occurred more often than in OAC_prior patients. The groups differed significantly in the distribution of competing etiologies underlying their stroke. At discharge, OAC_prior more frequently were (re)-anticoagulated compared to OAC_naive patients. Within the OAC_prior group, patients with recurrent strokes did not differ from those with a first stroke regarding clinical characteristics and pattern of cerebral infarction but they were less frequently anticoagulated.

CONCLUSIONS

Ischemic strokes on OAC represent a significant proportion of AF-related strokes. There is an unmet need to better understand the causes underlying these strokes and to optimize the medical management.

Decision-Making Process for the Management of Acute Stroke in Patients on Oral Anticoagulant: From Guidelines to Clinical Routine

Background: The occurrence of both ischaemic (IS) and haemorrhagic stroke in patients on anticoagulation is a major issue due to the frequency of their prescriptions in westernised countries and the expected impact of anticoagulant activity on recanalization during an IS or on the outcomes associated with intracerebral haemorrhage (ICH). Several guidelines are available but sometimes differ in their conclusions or regarding specific issues, and their application in routine emergency settings may be limited by particular individual issues or heterogeneous local specificities. Methods: Based on the current guidelines and additional published data, the algorithms proposed in this paper aim to help the decision-making process regarding stroke management in the setting of concurrent anticoagulants by addressing specific clinical situations based on clinical variables commonly encountered in real-world practise. Results: For patients on non-vitamin K oral anticoagulants, reversion can be achieved with specific antidotes, but only idarucizumab, the specific dabigatran antidote, is indicated in both IS and ICH. Due to the low risk of a prothrombotic effect, idarucizumab can be immediately used in IS patients eligible for thrombolysis before the dabigatran concentration is known. To optimise ICH management, the time since symptom onset, with thresholds proposed at 6 and 9 hours based on the expected timing of haematoma expansion, could also to be taken into account. Conclusions: Anticoagulant reversal in patients presenting with a stroke remains a major issue, and algorithms based on a step-by-step approach may be useful for clinical practise. Real-life studies strongly support the benefits of idarucizumab availability in stroke units and emergency departments.

Management of stroke in patients on antithrombotic therapy: Practical issues in the era of direct oral anticoagulants

Antithrombotic drugs (ADs) are the mainstay of secondary prevention of thrombotic vascular diseases. Management of patients under long-term treatment with ADs admitted for acute cerebrovascular disease, either ischemic stroke (IS) or intracerebral hemorrhage (ICH), has become a frequent situation that might influence decision-making processes from diagnosis to therapeutic strategies. The aim of this review is to summarize current data from the literature to help clinicians in their decisions for stroke care in patients taking ADs. While a large body of data have made it possible to codify the management of patients presenting IS or ICH under antiplatelet drugs and vitamin K antagonists, the increasing use of direct oral anticoagulants (DOAs) and future development of new antiplatelet drugs raise new problems. Development of rapid assessment tools measuring specific biological activity and reversion agents dedicated to each class of DOAs should make it possible to optimize individual therapeutic strategies. This review highlights the main steps of IS and ICH management from early identification of ADs, and use of dedicated biological assays, to the stepwise strategy to apply revascularization or reversal therapies and finally the resumption of ADs with a focus on individual clinical and radiological characteristics for more personalized care.

Ischemic Stroke Risk Factors in Patients with Atrial Fibrillation Treated with New Oral Anticoagulants

The most commonly used therapeutic option for the prevention of ischemic stroke in patients with atrial fibrillation is new- or old-generation oral anticoagulants. New oral anticoagulants are at least as effective as old-generation oral anticoagulants in the prevention of ischemic stroke, with a reduced risk of life-threatening hemorrhage. Moreover, the constant monitoring of these drugs in the patient’s blood is not required during routine use. However, ischemic stroke can still occur in these patients. Therefore, the aim of this study was to investigate the pattern of risk factors for ischemic stroke in patients with atrial fibrillation treated with new oral anticoagulants. Our multicenter retrospective study involved 2032 patients with acute ischemic stroke. The experimental group consisted of 256 patients with acute ischemic stroke and nonvalvular atrial fibrillation, who were treated with new oral anticoagulants. The control group consisted of 1776 ischemic stroke patients without coexisting atrial fibrillation. The results of our study show that patients with atrial fibrillation treated with new oral anticoagulants are more likely to display thrombotic, proatherogenic, and proinflammatory factors in addition to the embolic factors associated with atrial fibrillation. Therefore, solely taking new oral anticoagulants is insufficient in protecting this group of patients from ischemic stroke.

Prior Anticoagulation and Short- or Long-Term Clinical Outcomes in Ischemic Stroke or Transient Ischemic Attack Patients With Nonvalvular Atrial Fibrillation

Background

We aimed to clarify associations between prior anticoagulation and short‐ or long‐term clinical outcomes in ischemic stroke or transient ischemic attack patients with nonvalvular atrial fibrillation.

Methods and Results

A total of 1189 ischemic stroke or transient ischemic attack patients with nonvalvular atrial fibrillation who were hospitalized within 7 days after onset were analyzed. Of these, 813 patients (68.4%) received no prior anticoagulation, 310 (26.1%) received prior warfarin treatment with an international normalized ratio (INR) <2 on admission, 28 (2.4%) received prior warfarin treatment with an INR ≥2 on admission, and the remaining 38 (3.2%) received prior direct oral anticoagulant treatment. Prior warfarin treatment was associated with a lower risk of death or disability at 3 months compared with no prior anticoagulation (INR <2: adjusted odds ratio: 0.58; 95% CI, 0.42–0.81; P=0.001; INR ≥2: adjusted odds ratio: 0.40; 95% CI, 0.16–0.97; P=0.043) but was not associated with a lower risk of death or disability at 2 years. Prior warfarin treatment with an INR ≥2 on admission was associated with a higher risk of ischemic events within 2 years compared with no prior anticoagulation (adjusted hazard ratio: 2.94; 95% CI, 1.20–6.15; P=0.021).

Conclusions

Prior warfarin treatment was associated with a lower risk of death or disability at 3 months but was not associated with a lower risk of death or disability at 2 years in ischemic stroke or transient ischemic attack patients with nonvalvular atrial fibrillation. Prior warfarin treatment with an INR ≥2 on admission was associated with a higher risk of ischemic events within 2 years.

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01581502.

Ischemic Stroke despite Oral Anticoagulant Therapy in Patients with Atrial Fibrillation

OBJECTIVE

It is not known whether patients with atrial fibrillation (AF) with ischemic stroke despite oral anticoagulant therapy are at increased risk for further recurrent strokes or how ongoing secondary prevention should be managed.

METHODS

We conducted an individual patient data pooled analysis of 7 prospective cohort studies that recruited patients with AF and recent cerebral ischemia. We compared patients taking oral anticoagulants (vitamin K antagonists [VKA] or direct oral anticoagulants [DOAC]) prior to index event (OACprior ) with those without prior oral anticoagulation (OACnaive ). We further compared those who changed the type (ie, from VKA or DOAC, vice versa, or DOAC to DOAC) of anticoagulation (OACchanged ) with those who continued the same anticoagulation as secondary prevention (OACunchanged ). Time to recurrent acute ischemic stroke (AIS) was analyzed using multivariate competing risk Fine-Gray models to calculate hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

We included 5,413 patients (median age = 78 years [interquartile range (IQR) = 71-84 years]; 5,136 [96.7%] had ischemic stroke as the index event, median National Institutes of Health Stroke Scale on admission = 6 [IQR = 2-12]). The median CHA2 DS2 -Vasc score (congestive heart failure, hypertension, age≥ 75 years, diabetes mellitus, stroke/transient ischemic attack, vascular disease, age 65-74 years, sex category) was 5 (IQR = 4-6) and was similar for OACprior (n = 1,195) and OACnaive (n = 4,119, p = 0.103). During 6,128 patient-years of follow-up, 289 patients had AIS (4.7% per year, 95% CI = 4.2-5.3%). OACprior was associated with an increased risk of AIS (HR = 1.6, 95% CI = 1.2-2.3, p = 0.005). OACchanged (n = 307) was not associated with decreased risk of AIS (HR = 1.2, 95% CI = 0.7-2.1, p = 0.415) compared with OACunchanged (n = 585).

INTERPRETATION

Patients with AF who have an ischemic stroke despite previous oral anticoagulation are at a higher risk for recurrent ischemic stroke despite a CHA2 DS2 -Vasc score similar to those without prior oral anticoagulation. Better prevention strategies are needed for this high-risk patient group. ANN NEUROL 2020.