Direct oral anticoagulants in the early phase of non valvular atrial fibrillation-related acute ischemic stroke: focus on real life studies

Early Versus Delayed Non-Vitamin K Antagonist Oral Anticoagulant Therapy After Acute Ischemic Stroke in Atrial Fibrillation (TIMING): A Registry-Based Randomized Controlled Noninferiority Study

BACKGROUND

There are no evidence-based recommendations on the optimal time point to initiate non-vitamin K antagonist oral anticoagulants (NOACs) after acute ischemic stroke in patients with atrial fibrillation. We aimed to investigate the efficacy and safety of early versus delayed initiation of NOAC in these patients.

METHODS

TIMING (Timing of Oral Anticoagulant Therapy in Acute Ischemic Stroke With Atrial Fibrillation) was a registry-based, randomized, noninferiority, open-label, blinded end-point study at 34 stroke units using the Swedish Stroke Register for enrollment and follow-up. Within 72 hours from stroke onset, patients were randomized to early (≤4 days) or delayed (5-10 days) NOAC initiation, with choice of NOAC at the investigators' discretion. The primary outcome was the composite of recurrent ischemic stroke, symptomatic intracerebral hemorrhage, or all-cause mortality at 90 days. The prespecified noninferiority margin was 3%. Secondary outcomes included the individual components of the primary outcome.

RESULTS

Between April 2, 2017, and December 30, 2020, 888 patients were randomized to either early (n=450) or delayed (n=438) initiation of NOAC. No patient was lost to 90-day follow-up. Mean age was 78.3 years (SD, 9.9 years); 46.2% were women; 49.1% had previously known atrial fibrillation; and 17.5% prior stroke. The primary outcome occurred in 31 patients (6.89%) assigned to early initiation and in 38 patients (8.68%) assigned to delayed NOAC initiation (absolute risk difference, -1.79% [95% CI, -5.31% to 1.74%]; P_{noninferiority}=0.004). Ischemic stroke rates were 3.11% and 4.57% (risk difference, -1.46% [95% CI, -3.98% to 1.07%]) and all-cause mortality rates were 4.67% and 5.71% (risk difference, -1.04% [95% CI, -3.96% to 1.88%]) in the early and delayed groups, respectively. No patient in either group experienced symptomatic intracerebral hemorrhage.

CONCLUSIONS

Early initiation was noninferior to delayed start of NOAC after acute ischemic stroke in patients with atrial fibrillation. Numerically lower rates of ischemic stroke and death and the absence of symptomatic intracerebral hemorrhages implied that the early start of NOAC was safe and should be considered for acute secondary stroke prevention in patients eligible for NOAC treatment.

REGISTRATION

URL: http://www.

CLINICALTRIALS

gov; Unique identifier: NCT02961348.

Identifying gaps in the management of atrial fibrillation with anticoagulation for stroke prevention (GIANTS): a quality improvement initiative

OBJECTIVES

Direct oral anticoagulants (DOACs) are indicated for preventing ischemic stroke in 95% of patients with atrial fibrillation (AF). However, DOACs are largely underutilized or inappropriately dosed. This study aimed to explore the rates of appropriate DOAC use between repatriated and non-repatriated patients with AF who presented with an acute ischemic stroke not deemed candidates for revascularization therapies.

MATERIALS AND METHODS

Data were collected via electronic medical records and patients were contacted via telephone to obtain medication information and other missing clinical information. Multivariate logistic regression analyses were conducted to determine associations between appropriate use of a DOAC and repatriation status adjusting for age, sex, and comorbidities.

RESULTS

A total of 49 patients were included in the study with a mean follow-up of 31.5 (± 11.9) months. Eleven patients (22.4%) died, and 4 (8.2%) patients were lost to follow-up. Overall, 9 (26.5%) patients (3 non-repatriated and 6 repatriated) were found to be on suboptimal or inappropriate anticoagulation. Repatriation was associated with over six fold (OR 6.53; 95% CI 1.20-35.7) likelihood of suboptimal or inappropriate anticoagulation.

CONCLUSIONS

Awareness of this finding is critical to overcome therapeutic inertia in the use of DOACs for ischemic stroke patients with AF. With stroke care becoming increasingly nuanced, peripheral centers may lack the ability to guide anticoagulation in a timely and effective manner. Creation of tertiary short-term follow-up stroke clinics with cardiology follow-up may be an effective strategy to ensure standard of care. Research into systems contributors affecting the appropriate use of DOACs should be elucidated.

Practical "1-2-3-4-Day" Rule for Starting Direct Oral Anticoagulants After Ischemic Stroke With Atrial Fibrillation: Combined Hospital-Based Cohort Study

BACKGROUND

The "1-3-6-12-day rule" for starting direct oral anticoagulants (DOACs) in patients with nonvalvular atrial fibrillation after acute ischemic stroke or transient ischemic attack recommends timings that may be later than used in clinical practice. We investigated more practical optimal timing of DOAC initiation according to stroke severity.

METHODS

The combined data of prospective registries in Japan, Stroke Acute Management with Urgent Risk-factor Assessment and Improvement-nonvalvular atrial fibrillation (September 2011 to March 2014) and RELAXED (February 2014 to April 2016) were used. Patients were divided into transient ischemic attack and 3 stroke subgroups by the National Institutes of Health Stroke Scale score: mild (0-7), moderate (8-15), and severe (≥16). The early treatment group was defined as patients starting DOACs earlier than the median initiation day in each subgroup. Outcomes included a composite of recurrent stroke or systemic embolism, ischemic stroke, and severe bleeding within 90 days. Six European prospective registries were used for validation.

RESULTS

In the 1797 derivation cohort patients, DOACs were started at median 2 days after transient ischemic attack and 3, 4, and 5 days after mild, moderate, and severe strokes, respectively. Stroke or systemic embolism was less common in Early Group (n=785)-initiating DOACS within 1, 2, 3, and 4 days, respectively-than Late Group (n=1012) (1.9% versus 3.9%; adjusted hazard ratio, 0.50 [95% CI, 0.27-0.89]), as was ischemic stroke (1.7% versus 3.2%, 0.54 [0.27-0.999]). Major bleeding was similarly common in the 2 groups (0.8% versus 1.0%). On validation, both ischemic stroke (2.4% versus 2.2%) and intracranial hemorrhage (0.2% versus 0.6%) were similarly common in Early (n=547) and Late (n=1483) Groups defined using derivation data.

CONCLUSIONS

In Japanese and European populations, early DOAC initiation within 1, 2, 3, or 4 days according to stroke severity seemed to be feasible to decrease the risk of recurrent stroke or systemic embolism and no increase in major bleeding. These findings support ongoing randomized trials to better establish the optimal timing of DOAC initiation.

Management of oral anticoagulation in very old patients with non valvular atrial fibrillation related acute ischemic stroke

The optimal management of oral anticoagulation (OAC) in the acute phase of non valvular atrial fibrillation (NVAF)-related acute ischemic stroke (AIS) remains controversial, especially in very old patients. Therefore, the aim of our study was to evaluate the practical management of OAC in this context. We conducted an observational retrospective study on patients 85-years old and older admitted to two Italian hospitals for NVAF-related AIS. For each patient, clinical and brain computed tomography data were recorded. Type of OAC (vitamin K antagonists, VKAs or Direct Oral Anticoagulants, DOACs), dosage and starting day after AIS were registered. For each patient 90-day all cause mortality, stroke recurrence, any bleeding and modified Rankin scale (mRS) were reported. One-hundred-seventeen patients, with mean age 89.2 ± 3.4 years, were enrolled. In-hospital and 90-day mortality (out of 109 patients) were 6% and 19.7%, respectively. OAC was started in 93 patients (80.5%), on average after 6 ± 3 days from the acute event. Of them, 88 patients (94.6%) received DOACs, while 5 (5.4%) received VKAs. Patients receiving OAC were significantly younger and suffering from less severe stroke compared with patients who did not receive OAC. Patients receiving OAC presented a reduced in-hospital (2.2% vs. 20.8%, p < 0.004) and 90-day all-cause mortality (9.4% vs. 62.5%, p < 0.001). In patients receiving DOACs, low dosages were used in 87.5% of patients. The use of OAC was not associated with an increased rate of hemorrhagic transformation (HT) during hospitalization (13.2% vs. 9.5%, p = 0.54) or any bleeding at 90-day follow-up. Severe dysphagia and mRS ≥ 4 were found to be independent risk factors for not prescribing OAC. The optimal management of OAC in very old patients suffering from NVAF-related AIS remains a dilemma. In our real world study the majority of patients received OAC as secondary prevention treatment without increase in bleeding risk. Dysphagia and severe disability were independent factors for not prescribing OAC. Further investigations aimed at identifying the optimal approach to OAC during the acute phase of NVAF-related ischemic stroke in this subgroup of patients are warranted.

Age-related burden and characteristics of embolic stroke of undetermined source in the real world clinical practice

Few data are available on age-related burden and characteristics of embolic stroke of undetermined source (ESUS) in the real world clinical practice. The aim of our study was to provide information about it. We retrospectively analyzed data of patients consecutively admitted to our Stroke Unit along 1 year (2017, November 1st-2018, October 31st). The etiology of ischemic stroke was defined at hospital discharge; ESUS was considered as a subset of cryptogenic stroke, and defined according to the 2014 international criteria. In the analyzed period, 306 patients, 52.3% females, mean age ± SD 77.9 ± 11.9 years, were discharged with diagnosis of ischemic stroke. Ischemic strokes of cardioembolic and lacunar origin were the most frequent subtypes: 30.1% and 29.4%, respectively. Cardioembolic strokes were particularly frequent in patients ≥ 75 years, and almost always associated with atrial fibrillation. Overall, in 80 patients (26.1%) the etiology of stroke was undetermined; in 25 (8.2%) it remained undefined because of death or severe comorbidity, making further diagnostic work-up not worthy. Cryptogenic stroke occurred in 55 patients (18%), and ESUS criteria were satisfied in 39 of them (12.7%). According to age, cryptogenic stroke was diagnosed in 21.1% (21.1% ESUS) of patients < 65 years, 24.2% (19.4% ESUS) of patients aged 65-74 years, 15.5% (9.2% ESUS) of patients ≥ 75 years. After diagnostic work-up, patent foramen ovale was most commonly associated with ESUS (17.9%), especially in patients < 65 years (62.5%); covert paroxysmal atrial fibrillation was detected in 10.5% of ESUS patients ≥ 75 years. In the real world clinical practice, the frequency of ischemic strokes of undetermined etiology, and of those satisfying ESUS criteria, is not negligible, especially in younger patients. A thorough diagnostic work-up, with an age-specific approach, is therefore necessary and of the utmost importance for the identification of stroke etiology, in order to optimize secondary stroke prevention strategies.

Direct Oral Anticoagulants in Patients Undergoing Urgent Reperfusion for Nonvalvular Atrial Fibrillation-Related Ischemic Stroke: A Brief Report on Literature Evidence

Introduction

The optimal timing for starting anticoagulation in the early phase of nonvalvular atrial fibrillation (NVAF)-related acute ischemic stroke (AIS) remains a challenge, especially in patients undergoing urgent reperfusion by systemic thrombolysis or mechanical thrombectomy. The aim of our study was to review the literature evidence reporting on safety of direct oral anticoagulants (DOACs) starting in the early phase of NVAF-related AIS undergoing systemic thrombolysis and/or mechanical thrombectomy.

Materials and Methods

We reviewed the PubMed databases searching articles reporting on efficacy and safety of DOACs starting time within two weeks from AIS onset in patients undergoing systemic thrombolysis and/or mechanical thrombectomy.

Results

Three studies were selected, overall including one hundred and six patients (62 females, 58.4%). Median National Institute of Health Stroke Scale (NIHSS) score at hospital admission ranged from 9 to 13 points. Median DOACs starting time ranged from 2 to 6 days. Median CHA₂DS₂-VASC score ranged from 4 to 6 points. Follow-up was limited to 14 days in one study, 30 days in another, and 90 days in a third one. Overall, stroke recurrence and/or intracranial bleeding occurred in two patients (1.9%) and no patient died at follow-up.

Conclusion

Small sample size real life studies seem to demonstrate that the introduction of DOACs in the early phase of NVAF-related AIS undergoing urgent reperfusion is efficacious and safe. Prospective RCTs are necessary to confirm these findings.