To Treat or Not to Treat?

Dual-Energy CT in Acute Stroke: Could Non-Contrast CT Be Replaced by Virtual Non-Contrast CT? A Feasibility Study

Purpose: We aimed to evaluate whether virtual non-contrast cerebral computed tomography (VNCCT) reconstructed from intravenous contrast-enhanced dual-energy CT (iv-DECT) could replace non-contrast CT (NCCT) in patients with suspected acute cerebral ischemia. Method: This retrospective study included all consecutive patients in whom NCCT followed by iv-DECT were performed for suspected acute ischemia in our emergency department over a 1-month period. The Alberta Stroke Program Early CT Score (ASPECTS) was used to determine signs of acute ischemia in the anterior and posterior circulation, the presence of hemorrhage, and alternative findings, which were randomly evaluated via the consensus reading of NCCT and VNCCT by two readers blinded to the final diagnosis. An intraclass correlation between VNCCT and NCCT was calculated for the ASPECTS values. Both techniques were evaluated for their ability to detect ischemic lesions (ASPECTS <10) when compared with the final discharge diagnosis (reference standard). Results: Overall, 148 patients (80 men, mean age 64 years) were included, of whom 46 (30%) presented with acute ischemia, 6 (4%) presented with intracerebral hemorrhage, 11 (7%) had an alternative diagnosis, and 85 (59%) had no pathological findings. The intraclass correlation coefficients of the two modalities were 0.97 (0.96-0.98) for the anterior circulation and 0.77 (0.69-0.83) for the posterior circulation. The VNCCT's sensitivity for detecting acute ischemia was higher (41%, 19/46) than that of NCCT (33%, 15/46). Specificity was similar between the two techniques, at 94% (97/103) and 98% (101/103), respectively. Conclusions: Our results show that VNCCT achieved a similar diagnostic performance as NCCT and could, thus, replace NCCT in assessing patients with suspected acute cerebral ischemia.

Biomarkers for Atrial Fibrillation Detection After Stroke: Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVE

To identify clinical, ECG, and blood-based biomarkers associated with atrial fibrillation (AF) detection after ischaemic stroke or TIA that could help inform patient selection for cardiac monitoring.

METHODS

We performed a systematic review and meta-analysis and searched electronic databases for cohort studies from January 15, 2000, to January 15, 2020. The outcome was AF ≥30 seconds within 1 year after ischemic stroke/TIA. We used random effects models to create summary estimates of risk. Risk of bias was assessed using the Quality in Prognostic Studies tool.

RESULTS

We identified 8,503 studies, selected 34 studies, and assessed 69 variables (42 clinical, 20 ECG, and 7 blood-based biomarkers). The studies included 11,569 participants and AF was detected in 1,478 (12.8%). Overall, risk of bias was moderate. Variables associated with increased likelihood of AF detection are older age (odds ratio [OR] 3.26, 95% confidence interval [CI] 2.35-4.54), female sex (OR 1.47, 95% CI 1.23-1.77), a history of heart failure (OR 2.56, 95% CI 1.87-3.49), hypertension (OR 1.42, 95% CI 1.15-1.75) or ischemic heart disease (OR 1.80, 95% CI 1.34-2.42), higher modified Rankin Scale (OR 6.13, 95% CI 2.93-12.84) or National Institutes of Health Stroke Scale score (OR 2.50, 95% CI 1.64-3.81), no significant carotid/intracranial artery stenosis (OR 3.23, 95% CI 1.14-9.11), no tobacco use (OR 1.93, 95% CI 1.48-2.51), statin therapy (OR 2.07, 95% CI 1.14-3.73), stroke as index diagnosis (OR 1.59, 95% CI 1.17-2.18), systolic blood pressure (OR 1.61, 95% CI 1.16-2.22), IV thrombolysis treatment (OR 2.40, 95% CI 1.83-3.16), atrioventricular block (OR 2.12, 95% CI 1.08-4.17), left ventricular hypertrophy (OR 2.21, 95% CI 1.03-4.74), premature atrial contraction (OR 3.90, 95% CI 1.74-8.74), maximum P-wave duration (OR 3.19, 95% CI 1.40-7.25), PR interval (OR 2.32, 95% CI 1.11-4.83), P-wave dispersion (OR 7.79, 95% CI 4.16-14.61), P-wave index (OR 3.44, 95% CI 1.87-6.32), QTc interval (OR 3.68, 95% CI 1.63-8.28), brain natriuretic peptide (OR 13.73, 95% CI 3.31-57.07), and high-density lipoprotein cholesterol (OR 1.49, 95% CI 1.17-1.88) concentrations. Variables associated with reduced likelihood are minimum P-wave duration (OR 0.53, 95% CI 0.29-0.98), low-density lipoprotein cholesterol (OR 0.73, 95% CI 0.57-0.93), and triglyceride (OR 0.51, 95% CI 0.41-0.64) concentrations.

DISCUSSION

We identified multimodal biomarkers that could help guide patient selection for cardiac monitoring after ischaemic stroke/TIA. Their prognostic utility should be prospectively assessed with AF detection and recurrent stroke as outcomes.

Which Road to Recovery?: Factors Influencing Postacute Stroke Discharge Destinations: A Delphi Study

BACKGROUND AND PURPOSE

The criteria for determining the level of postacute care for patients with stroke are variable and inconsistent. The purpose of this study was to identify key factors influencing the selection of postacute level of care for these patients.

METHODS

We used a collaborative 4-round Delphi process to achieve a refined list of factors influencing postacute level of care selection. Our Delphi panel of experts consisted of 32 panelists including physicians, physical therapists, occupational therapists, speech-language pathologists, nurses, stroke survivors, administrators, policy experts, and individuals associated with third-party insurance companies.

RESULTS

In round 1, 207 factors were proposed, with subsequent discussion resulting in consolidation into 15 factors for consideration. In round 2, 15 factors were ranked with consensus on 10 factors; in round 3,10 factors were ranked with consensus on 9 factors. In round 4, the final round, 9 factors were rated with Likert scores ranging from 5 (most important) to 1(not important). The percentage of panelists who provided a rating of 4 or above were as follows: likelihood to benefit from an active rehabilitation program (97%), need for clinicians with specialized rehabilitation skills (94%), need for active and ongoing medical management and monitoring (84%), ability to tolerate an active rehabilitation program (74%), need for caregiver training to return to the community (48%), family/caregiver support (39%), likelihood to return to community/home (39%), ability to return to physical home environment (32%), and premorbid dementia (16%).

CONCLUSIONS

This study provides an expert, consensus-based set of key factors to be considered when determining where stroke patients are discharged for postacute care. These factors may be useful in developing a decision support tool for use in clinical settings.

Managing Ischemic Stroke in Patients Already on Anticoagulation for Atrial Fibrillation: A Nationwide Practice Survey

BACKGROUND AND PURPOSE

We sought to understand practice patterns in management of patients who have ischemic stroke while adherent to oral anticoagulation for non-valvular atrial fibrillation (NVAF) in the United States (US).

METHODS

We distributed an iteratively revised online survey to US neurologists in May-June 2019. Survey questions focused on clinicians' practices regarding diagnostic evaluation and secondary prevention after ischemic stroke in patients already on oral anticoagulation for NVAF. Standard descriptive statistics were used to summarize participants' characteristics and responses.

RESULTS

Of the 120 participating clinicians, 79% were attending physicians. Most respondents (66%) were trained in vascular neurology, and 79% were employed in hospital-based, academic settings. For patients with ischemic stroke despite anticoagulation, most respondents indicated that they obtain extracranial and intracranial vessel imaging (72% and 82%, respectively). Most respondents (83%) routinely change therapy to a direct oral anticoagulant (DOAC) for patients experiencing ischemic stroke while on warfarin. In cases of ischemic stroke while on a DOAC, 38% of respondents routinely switch agents, 42% do not routinely switch agents, and 20% routinely add an antiplatelet agent. In this scenario, 83% of respondents who switch agents indicated that the reason was a possible better response to a drug that acts through a different mechanism. The most common reason for not switching while on a DOAC was the lack of randomized trial data.

CONCLUSIONS

There is a high degree of variability in practice patterns among US neurologists caring for patients with ischemic stroke while already on oral anticoagulation for NVAF.

Disability after minor stroke and TIA

Objective

To examine factors associated with disability following TIA and minor stroke, including poststroke complications such as stroke recurrence, major bleeding, and other adverse medical events.

Methods

The SOCRATES trial randomized patients with TIA/minor stroke (NIH Stroke Scale [NIHSS] score ≤5) within 24 hours of onset. We performed a post hoc analysis of factors associated with disability (modified Rankin Scale [mRS] score >1). TIA and minor stroke were analyzed separately. Patients with premorbid mRS >0 were excluded.

Results

At 90 days, 687/3,663 (19%) patients with stroke were disabled; for TIA, 122/2,384 (5%) were disabled. In multivariate analyses, age, diabetes, and NIHSS were associated with disability in the stroke cohort, and age with disability in the TIA cohort. Postrandomization events (recurrent stroke, myocardial infarction, major bleeding, serious adverse events) were strongly associated with disability in both cohorts (stroke cohort: odds ratio [OR] 5.6, 95% confidence interval [CI] 4.5–6.9; TIA cohort: OR 14.8, 95% CI 9.9–22.0). Of the TIA patients who ended up disabled, 65% experienced a postrandomization event; for stroke patients who ended up disabled, 39% had a postrandomization event. Disability increased linearly with NIHSS score (p < 0.0001) and was greater in those with limb weakness (p < 0.0001).

Conclusions

After TIA and minor stroke, subsequent stroke and medical complications are strongly associated with disability. In addition, even within a low range of baseline scores, the NIHSS is a powerful predictor of disability in minor stroke patients, with items scoring limb weakness particularly associated with subsequent disability.

Variability in the decision-making process of acute ischemic stroke in difficult clinical and radiological constellations: analysis based on a cross-sectional interview-administered stroke questionnaire

BACKGROUND AND PURPOSE

Notwithstanding guidelines, indications for mechanical thrombectomy (MT) in acute ischemic stroke are multifactorial and can be complex. Our aim was to exploratively evaluate decision-making on the advisability of performing MT in cases presented as an interview-administered questionnaire.

METHODS

Fifty international raters assessed 12 cases and decided to recommend or exclude MT. Each case contained a brief summary of clinical information and eight representative images of the initial multimodal CT. The demographic characteristics and stroke protocols were recorded for raters. For each case, the reasons for excluding MT were recorded. Uni- and multivariate logistic regression analysis were performed for the different demographic and case characteristics to identify factors that might influence decision-making.

RESULTS

All raters performed MT (median MTs/hospital/year [IQR], 100 [50-141]) with a median of 7 years of experience as first operator (IQR, 4-12). Per case, diversity in decision-making ranged between 1 (case 6, 100% yes MT) and 0.50 (case 12, 54.2% yes MT and 45.8% no MT). The most common reasons for excluding MT were small CBV/CBF mismatch (17%, 102/600), size of infarct core on the CBV map (15.2%, 91/600), and low NIHSS score (National Institute of Health Stroke Scale, 8.3%, 50/600). All clinical and radiological characteristics significantly affected the decision regarding MT, but the general characteristics of the raters were not a factor.

CONCLUSIONS

Clinical and imaging characteristics influenced the decision regarding MT in stroke. Nevertheless, a consensus was reached in only a minority of cases, revealing the current divergence of opinion regarding therapeutic decisions in difficult cases.

KEY POINTS

• This is the first study to explore differences in decision-making in respect of mechanical thrombectomy in ischemic stroke with complex clinical and radiological constellations. • Fifty experienced international neurointerventionalists answered this interview-administered stroke questionnaire and made decisions as to whether to recommend or disadvise thrombectomy in 12 selected cases. • Diversity in decision-making for thrombectomy ranged from 1 (100% of raters offered the same answer) to 0.5 (50% indicated mechanical thrombectomy). There was a consensus in only a minority of cases, revealing the current disparity of opinion regarding therapeutic decisions in difficult cases.

Clinical Decision-Making for Thrombolysis of Acute Minor Stroke Using Adaptive Conjoint Analysis

INTRODUCTION

There is practice variability in the treatment of patients with minor ischemic stroke with thrombolysis. We sought to determine which clinical factors physicians prioritize in thrombolysis decision-making for minor stroke using adaptive conjoint analysis.

METHODS

We conducted our conjoint analysis using the Potentially All Pairwise RanKings of all possible Alternatives methodology via the 1000Minds platform to design an online preference survey and circulated it to US physicians involved in stroke care. We evaluated 6 clinical attributes: language/speech deficits, motor deficits, other neurological deficits, history suggestive of increased risk of complication from thrombolysis, age, and premorbid disability. Survey participants were asked to choose between pairs of treatment scenarios with various clinical attributes; scenarios automatically adapted based on participants' prior responses. Preference weights representing the relative importance of each attribute were compared using unadjusted paired t tests. Statistical significance was set at α = .05.

RESULTS

Fifty-four participants completed the survey; 61% were vascular neurologists and 93% worked in academic centers. All neurological deficits were ranked higher than age, premorbid status, or potential contraindications to thrombolysis. Differences between each successive mean preference weight were significant: motor (31.7%, standard deviation [SD]: 9.5), language/speech (24.1%, SD: 9.6), other neurological deficits (16.6%, SD: 6.4), premorbid status (12.9%, SD: 6.6), age (10.1%, SD: 6.3), and potential thrombolysis contraindication (4.7%, SD: 4.4).

CONCLUSION

In a conjoint analysis, surveyed US physicians in academic practice assigned greater weight to motor and speech/language deficits than other neurological deficits, patient age, relative contraindications to thrombolysis, and premorbid disability when deciding to thrombolyse patients with minor stroke.