Urgent therapy for stroke. Part I. Pilot study of tissue plasminogen activator administered within 90 minutes

Safety and efficacy of active blood-pressure reduction to the recommended thresholds for intravenous thrombolysis in patients with acute ischaemic stroke in the Netherlands (TRUTH): a prospective, observational, cluster-based, parallel-group study

BACKGROUND

Intravenous thrombolysis is contraindicated in patients with ischaemic stroke with blood pressure higher than 185/110 mm Hg. Prevailing guidelines recommend to actively lower blood pressure with intravenous antihypertensive agents to allow for thrombolysis; however, there is no robust evidence for this strategy. Because rapid declines in blood pressure can also adversely affect clinical outcomes, several Dutch stroke centres use a conservative strategy that does not involve the reduction of blood pressure. We aimed to compare the clinical outcomes of both strategies.

METHODS

Thrombolysis and Uncontrolled Hypertension (TRUTH) was a prospective, observational, cluster-based, parallel-group study conducted across 37 stroke centres in the Netherlands. Participating centres had to strictly adhere to an active blood-pressure-lowering strategy or to a non-lowering strategy. Eligible participants were adults (≥18 years) with ischaemic stroke who had blood pressure higher than 185/110 mm Hg but were otherwise eligible for intravenous thrombolysis. The primary outcome was functional status at 90 days, measured using the modified Rankin Scale and assessed through telephone interviews by trained research nurses. Secondary outcomes were symptomatic intracranial haemorrhage, the proportion of patients treated with intravenous thrombolysis, and door-to-needle time. All ordinal logistic regression analyses were adjusted for age, sex, stroke severity, endovascular thrombectomy, and baseline imbalances as fixed-effect variables and centre as a random-effect variable to account for the clustered design. Analyses were done according to the intention-to-treat principle, whereby all patients were analysed according to the treatment strategy of the participating centre at which they were treated.

FINDINGS

Recruitment began on Jan 1, 2015, and was prematurely halted because of a declining inclusion rate and insufficient funding on Jan 5, 2022. Between these dates, we recruited 853 patients from 27 centres that followed an active blood-pressure-lowering strategy and 199 patients from ten centres that followed a non-lowering strategy. Baseline characteristics of participants from the two groups were similar. The 90-day mRS score was missing for 15 patients. The adjusted odds ratio (aOR) for a shift towards a worse 90-day functional outcome was 1·27 (95% CI 0·96-1·68) for active blood-pressure reduction compared with no active blood-pressure reduction. 798 (94%) of 853 patients in the active blood-pressure-lowering group were treated with intravenous thrombolysis, with a median door-to-needle time of 35 min (IQR 25-52), compared with 104 (52%) of 199 patients treated in the non-lowering group with a median time of 47 min (29-78). 42 (5%) of 852 patients in the active blood-pressure-lowering group had a symptomatic intracranial haemorrhage compared with six (3%) of 199 of those in the non-lowering group (aOR 1·28 [95% CI 0·62-2·62]).

INTERPRETATION

Insufficient evidence was available to establish a difference between an active blood-pressure-lowering strategy-in which antihypertensive agents were administered to reduce blood pressure below 185/110 mm Hg-and a non-lowering strategy for the functional outcomes of patients with ischaemic stroke, despite higher intravenous thrombolysis rates and shorter door-to-needle times among those in the active blood-pressure-lowering group. Randomised controlled trials are needed to inform the use of an active blood-pressure-lowering strategy.

FUNDING

Fonds NutsOhra.

Underrepresented and Underserved Populations in Neurological Research

Underserved and underrepresented populations have historically been excluded from neurological research. This lack of representation has implications for translation of research findings into clinical practice given the impact of social determinants of health on neurological disease risk, progression, and outcomes. Lack of inclusion in research is driven by individual-, investigator-, and study-level barriers as well as larger systemic injustices (e.g., structural racism, discriminatory practices). Although strategies to increase inclusion of underserved and underrepresented populations have been put forth, numerous questions remain about the most effective methodology. In this article, we highlight inclusivity patterns and gaps among the most common neurological conditions and propose best practices informed by our own experiences in engagement of local community organizations and collaboration efforts to increase underserved and underrepresented population participation in neurological research.

The Pitfalls of NIHSS: Time for a New Clinical Acute Stroke Severity Scoring System in the Emergency?

Stroke is the second leading cause of death and a major cause of disability worldwide. Stroke severity scales serve as reliable means to track a patient's neurological deficit, predict outcome, and guide treatment decisions in clinical practice. The National Institute of Health Stroke Scale (NIHSS) was introduced over 30 years ago, marking a significant milestone in the field of stroke. Over the years, there have been notable advancements in acute stroke care. Despite several modifications made to NIHSS, none has yet succeeded in effectively capturing all the complex effects of a stroke. This review focuses on the pitfalls of NIHSS and emphasizes the need for a quick and comprehensive clinical and upgraded version of the stroke severity rating scale.

Thrombectomy in Stroke Patients With Low Alberta Stroke Program Early Computed Tomography Score: Is Modified Thrombolysis in Cerebral Infarction (mTICI) 2c/3 Superior to mTICI 2b?

BACKGROUND AND PURPOSE

Outcomes following mechanical thrombectomy (MT) are strongly correlated with successful recanalization, traditionally defined as modified Thrombolysis in Cerebral Infarction (mTICI) ≥2b. This retrospective cohort study aimed to compare the outcomes of patients with low Alberta Stroke Program Early Computed Tomography Score (ASPECTS; 2-5) who achieved mTICI 2b versus those who achieved mTICI 2c/3 after MT.

METHODS

This study utilized data from the Stroke Thrombectomy and Aneurysm Registry (STAR), which combined databases from 32 thrombectomy-capable stroke centers between 2013 and 2023. The study included only patients with low ASPECTS who achieved mTICI 2b, 2c, or 3 after MT for internal carotid artery or middle cerebral artery (M1) stroke.

RESULTS

Of the 10,229 patients who underwent MT, 234 met the inclusion criteria. Of those, 98 (41.9%) achieved mTICI 2b, and 136 (58.1%) achieved mTICI 2c/3. There were no significant differences in baseline characteristics between the two groups. The 90-day favorable outcome (modified Rankin Scale score: 0-3) was significantly better in the mTICI 2c/3 group than in the mTICI 2b group (adjusted odds ratio 2.35; 95% confidence interval [CI] 1.18-4.81; P=0.02). Binomial logistic regression revealed that achieving mTICI 2c/3 was significantly associated with higher odds of a favorable 90-day outcome (odds ratio 2.14; 95% CI 1.07-4.41; P=0.04).

CONCLUSION

In patients with low ASPECTS, achieving an mTICI 2c/3 score after MT is associated with a more favorable 90-day outcome. These findings suggest that mTICI 2c/3 is a better target for MT than mTICI 2b in patients with low ASPECTS.

Admission blood pressure and clinical outcomes in patients with acute ischaemic stroke treated with intravenous alteplase and endovascular treatment versus endovascular treatment alone: A MR CLEAN-NO IV substudy

INTRODUCTION

High systolic blood pressure (SBP) is associated with poor functional outcome. We analysed whether the association of SBP with outcomes after endovascular treatment (EVT) is modified by prior intravenous thrombolysis (IVT).

PATIENTS AND METHODS

This was a post-hoc analysis of MR CLEAN-NO IV, a randomised trial of IVT with alteplase followed by EVT versus EVT alone, within 4.5 h from stroke onset. SBP was recorded on hospital admission. The primary outcome was 90-day modified Rankin Scale (mRS) score and secondary outcomes included symptomatic intracranial haemorrhage (sICH) and successful reperfusion (eTICI 2b-3), analysed with (ordinal) logistic regression. Estimates were calculated per 10 mmHg change in SBP. We assessed whether IVT modified the associations of SBP with these outcomes using multiplicative interaction terms.

RESULTS

Of 539 randomised patients, 266 received IVT. The association of SBP with mRS score was J-shaped, with an inflection point at 150 mmHg. Using 150 mmHg as a reference point, SBPs higher than 150 mmHg were associated with poor functional outcome (acOR: 1.23, 95% CI: 1.09-1.38), but lower SBPs were not (acOR: 1.14, 95% CI: 0.99-1.30). Higher SBP was not associated with the risk of sICH (aOR: 1.09, 95% CI: 0.93-1.27) nor with the probability of successful reperfusion (aOR: 1.00, 95% CI: 0.91-1.10). Our main result was that we found no effect modification by IVT (p-values for interaction, mRS = 0.94; sICH = 0.26; successful reperfusion = 0.58).

DISCUSSION AND CONCLUSION

There was no effect modification of IVT with SBP for any of the clinical outcomes. Therefore, the level of SBP (if ⩽185/110 mmHg) should not guide IVT decisions in patients otherwise eligible for both IVT and EVT within the 4.5-h time window.

TRIAL REGISTRATION

ISRCTN80619088, https://www.isrctn.com/ISRCTN80619088.

Thrombus composition and thrombolysis resistance in stroke

A State of the Art lecture titled "Thrombus Composition and Thrombolysis Resistance in Stroke" was presented at the ISTH Congress in 2022. Intravenous thrombolysis (IVT) remains the only pharmacologic option to re-establish cerebral perfusion at the acute phase of ischemic stroke. IVT is based on the administration of recombinant tissue plasminogen activator with the objective of dissolving fibrin, the major fibrillar protein component of thrombi. Almost 30 years on from its introduction, although the clinical benefits of IVT have been clearly demonstrated, IVT still suffers from a relatively low efficacy, with a rate of successful early recanalization below 50% overall. Analyses of thrombectomy-recovered acute ischemic stroke (AIS) thrombi have shown that apart from occlusion site, thrombus length, and collateral status, AIS thrombus structure and composition are also important modulators of IVT efficacy. In this article, after a brief presentation of IVT principle and current knowledge on IVT resistance, we review recent findings on how compaction and structural alterations of fibrin together with nonfibrin thrombus components such as neutrophil extracellular traps and von Willebrand factor interfere with IVT in AIS. We further discuss how these new insights could soon result in the development of original adjuvant therapies for improved IVT in AIS. Finally, we summarize relevant new data presented during the 2022 ISTH Congress.

Intravenous Thrombolysis for Acute Ischemic Stroke

OBJECTIVE

This article reviews the history of IV thrombolysis, its current indications and implementation, the duality of the "time is brain" versus "tissue clock" approaches, the impact of endovascular thrombectomy on IV thrombolysis, the emergence of tenecteplase, and future research directions.

LATEST DEVELOPMENTS

The growing use of factor Xa inhibitors has increasingly caused patients with stroke to be excluded from treatment with IV thrombolysis. Important geographic, socioeconomic, sex, race, and ethnic disparities have been identified in the implementation of IV thrombolysis and need to be overcome. IV thrombolysis substantially improves outcomes when provided within the first golden hour after stroke onset in patients treated in mobile stroke units, supporting the "time is brain" concept and encouraging the possible value of more widespread implementation of the mobile stroke unit approach. At the same time, other studies have shown that IV thrombolysis can be successful in patients whose "tissue clock" is still ticking up to 9 hours after stroke onset or in patients who awaken with their stroke, as demonstrated by favorable imaging profiles. These considerations, along with the emergence of endovascular thrombectomy, have fostered examination of our care systems, including the "drip and ship" versus direct to comprehensive or endovascular thrombectomy stroke center approaches, as well as the possibility of skipping IV thrombolysis in certain patients treated with endovascular thrombectomy. Data suggesting that tenecteplase is at least noninferior to alteplase, as well as its more convenient dosing, has led to its increased use. Ongoing studies are evaluating newer thrombolytics and adding antithrombotic therapy to IV thrombolysis.

ESSENTIAL POINTS

IV thrombolysis remains the most common acute stroke treatment. Advances in acting faster to treat stroke have increased its efficacy, and advances in imaging have expanded its use. However, implementing these advances and overcoming disparities in IV thrombolysis use remain major challenges.

An Analysis of Right Hemisphere Stroke Discourse in the Modern Cookie Theft Picture

PURPOSE

Adults with right hemisphere damage demonstrate differences in connected speech compared to controls, but systematic, quantitative methods to capture these differences are lacking. The current study aimed to (a) investigate if measures using the Modern Cookie Theft picture description would identify discourse differences in acute right hemisphere stroke, and (b) examine if discourse differences were associated with documented cognitive impairment.

METHOD

Eighty-four participants completed the Modern Cookie Theft picture description within 5 days of right hemisphere stroke. Descriptions were analyzed for multiple microlinguistic characteristics. Medical charts were retrospectively reviewed for documented presence of cognitive impairment.

RESULTS

Individuals with acute right hemisphere stroke produced fewer content units, total syllables, and lower left-right content unit ratios compared to controls, indicating a paucity of informativeness. Presence of cognitive impairment was associated with fewer content units produced.

CONCLUSIONS

Multiple measures of microlinguistic discourse characteristics differentiated adults with right hemisphere stroke from controls, highlighting variations in both the quantity and quality of connected speech. Findings continue to underscore the contribution and correlation between cognitive skills and discourse performance. Future work is needed to assess the relationship between particular cognitive domains and discourse production as well as to investigate longitudinal changes to discourse production during stroke recovery.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.20778541.

Low-dose alteplase for the management of acute ischemic stroke in South Asians: A systematic review on cost, efficacy and safety

INTRODUCTION

South Asia is responsible for more than 40% of the stroke burden and stroke mortality in the developing world. South Asia, which is home to one-fourth of the world's population, is the most densely populated and one of the poorest regions. The majority of patients in this region are unable to afford intravenous thrombolysis (IVT) for acute ischemic stroke (AIS). If low-dose alteplase proves effective and safe in South Asians, it may be a more cost-effective treatment option.

METHODS

The study was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and meta-Analyses) guideline. Researchers searched PubMed, EMBASE, and Google Scholar for English literature from 2005 to 2021. END, ENI, good functional outcome, SICH, and all-cause mortality were used to assess efficacy and safety.

RESULTS

In the low-dose alteplase treated patients, different studies reported 32 to 57% ENI 24 h after IVT, and 7% to 9.7% END. At 3 months follow-up, good functional outcome was achieved by 48%-76.92% of low-dose alteplase treated patients. SICH rates ranged from 0% to 16.6% across studies. Asymptomatic ICH occurred in 5-14% of patients. The mortality rate in all included studies varied from none to 25%.

CONCLUSION

Our systematic review demonstrates that the use of low-dose alteplase for AIS in the South Asians offer comparable efficacy and reduced risk of SICH at a significantly lower cost than standard alteplase dose. Future well-randomized clinical trials are necessary to validate the findings of our study.

Predictors of early neurologic deterioration (END) following stroke thrombectomy

BACKGROUND

Early neurologic deterioration (END) following ischemic stroke is a serious event and is associated with poor outcomes. However, the incidence and predictors of END after stroke thrombectomy for emergent large vessel occlusion are largely unknown.

METHODS

The baseline characteristics of patients enrolled in the COMPASS trial (NCT02466893) were analyzed. The primary outcome was worsening of ≥4 National Institutes of Health Stroke Scale (NIHSS) points 24 hours post thrombectomy (4+ END₂₄) and the secondary outcome was deterioration of ≥2 points (2+ END₂₄).

RESULTS

Among 270 patients, 27 (10%) developed 4+ END₂₄ and 42 (16%) had 2+ END₂₄. Those with 4+ END₂₄ were older (76.4±12.9 vs 70.9±12.9 years; p=0.04), had a higher prevalence of hypertension (96% vs 69%; p=0.003), diabetes (41% vs 27%; p=0.13) and higher pretreatment systolic blood pressure (SBP) (170.4±32.6 vs 157.6±28.1 mmHg; p=0.03). More 4+ END₂₄ patients had failed reperfusion: Thrombolysis in Cerebral Infarction ≤2a (26% vs 8%; p=0.003). In unadjusted analysis, older patients and those with hypertension, diabetes, elevated SBP and failed reperfusion had higher odds of 4+ END₂₄. In adjusted analysis, age increase by 5 years led to an increase in 4+ END₂₄ of 28%, diabetes increased odds of 2.6 and failed reperfusion increased odds of 4.5. In the multivariable analysis for the secondary outcome, age (OR 1.33; 95% CI 1.109 to 1.593), diabetes (OR 2.7; 95% CI 1.247 to 5.764) and failed reperfusion (OR 7.2; 95% CI 0.055 to 0.349) were also significant predictors of 2+ END₂₄.

CONCLUSIONS

Older patients with acute ischemic stroke who have a history of diabetes or hypertension, with elevated pretreatment SBP and failed reperfusion are at a higher risk of END following stroke thrombectomy for emergent large vessel occlusion.

Pharmacogenetics studies in stroke patients treated with rtPA: a review of the most interesting findings

Recombinant tissue-plasminogen activator (rtPA) is the only drug used during the acute phase of stroke. Despite its important benefits, a percentage of patients suffer symptomatic hemorrhagic transformations or a lack of early recanalization rates. These undesirable effects are associated with acute neurological and long-term functional deterioration. For the past 20 years, pharmacogenetic studies have tried to find the genetic risk factors associated with rtPA response. Most of these studies have used a gene-candidate strategy; however, recent genome-wide association studies have emerged indicating that genetic predisposition could modulate rtPA response. This review summarizes the most interesting findings in this field, including which genes and genetic variations are associated with hemorrhagic transformations and recanalization rates after thrombolytic therapy.

Delayed massive cerebral infarction after perioperative period of anterior cervical discectomy and fusion: A case report

BACKGROUND

Cerebral infarction is an extremely rare postoperative complication of anterior cervical discectomy and fusion (ACDF), particularly in the delayed setting. We present a case who had a sudden stroke on day 18 after surgery. By sharing our experience with this case, we hope to provide new information about stroke after anterior cervical surgery.

CASE SUMMARY

We present the case of a 61-year-old man with more than 20 years of hypertension and 14 years of coronary heart disease who had suffered a stroke 11 years ago. The patient was admitted for a multiple ACDF due to symptoms of cervical spondylotic myelopathy and had a sudden stroke on day 18 after surgery. Imaging findings showed a large-area infarct of his left cerebral hemisphere and thrombosis in his left common carotid artery. With the consent of his family, the thrombus was removed and a vascular stent was implanted through an interventional operation. Forty days later, the patient was transferred to a rehabilitation hospital for further treatment. He had normal consciousness but slurred speech at the 1-year follow-up evaluation. The motor and sensory functions of his hemiplegic limbs partially recovered.

CONCLUSION

This case illustrated that a postoperative stroke related to anterior cervical surgery may be attributed to prolonged carotid retraction and might have a long silent period. Preventive measures include careful preoperative and postoperative examination for high-risk patients as well as gentle and intermittent retraction of carotid artery sheath during operation.

Adapting Clinical Practice of Thrombolysis for Acute Ischemic Stroke Beyond 4.5 Hours: A Review of the Literature

Several clinical trials have demonstrated that advanced neuroimaging can select patients for recanalization therapy in an extended time window. The favorable functional outcomes and safety profile of these studies have led to the incorporation of neuroimaging in endovascular treatment guidelines, and most recently, also extended to decision making on thrombolysis. Two randomized clinical trials have demonstrated that patients who are not amenable to endovascular thrombectomy within 4.5 hours from symptoms discovery or beyond 4.5 hours from the last-known-well time may also be safely treated with intravenous thrombolysis and have a clinical benefit above the risk of safety concerns. With the growing aging population, increased stroke incidence in the young, and the impact of evolving medical practice, healthcare and stroke systems of care need to adapt continuously to provide evidence-based care efficiently. Therefore, understanding and incorporating appropriate screening strategies is critical for the prompt recognition of potentially eligible patients for extended-window intravenous thrombolysis. Here we review the clinical trial evidence for thrombolysis for acute ischemic stroke in the extended time window and provide a review of new enrolling clinical trials that include thrombolysis intervention beyond the 4.5 hour window.

Cerebral Perfusion Imaging for Intravenous Thrombolysis Treatment

ABSTRACT

Intravenous thrombolysis is the cornerstone of acute ischemic stroke treatment. However, the benefits of recanalization and reperfusion must be balanced against the risk of intracranial hemorrhage. Time from symptom onset was previously the most important selection tool for identifying patients who would benefit from treatment without prohibitive risk for secondary hemorrhage. Enhanced techniques in noncontrast computed tomography followed by computed tomography and magnetic resonance perfusion imaging led to the expansion of treatment eligibility for intravenous thrombolysis. Perfusion imaging allows for more precise evaluation of tissue at-risk to identify patients who would benefit from treatment many hours beyond symptom onset.

Maximum intravenous alteplase dose for obese stroke patients is not associated with greater likelihood of worse outcomes

BACKGROUND

IV alteplase is a primary treatment for acute ischemic stroke (AIS) at a weight-based dose (WBD) of 0.9 mg/kg and maximum dose (MD) of 90 mg. There are conflicting data regarding outcomes for those weighing ≥100 kg. There is also a paucity of data in Hispanics. The prevalence of adult obesity in the US has progressively increased; hence, the percentage of patients receiving the maximum dose also is expected to rise. We examined differences between patients treated with WBD vs. MD.

METHODS

A retrospective review of our center's Get With The Guidelines-Stroke database was performed for IV alteplase cases between October 2013-February 2017. Selection criteria included age ≥18 years, IV alteplase administration, and a recorded measured weight. Patients were dichotomized into WBD group weighing <100 kg and MD group weighing ≥100 kg. Categorical variables were analyzed using Chi square tests and continuous variables were analyzed using independent samples t-tests. Multivariable logistic regression analysis was performed to determine whether MD in combination with other variables was associated with poor outcomes.

RESULTS

There were 328 patients included in the study, 38 (11.6%) received MD. Proportions of younger, male, and non-Hispanic were higher in the MD group. There were no statistically significant differences for initial NIHSS, discharge modified Rankin Scale (mRS), 90-day mRS, symptomatic intracerebral hemorrhage (sICH), or systemic hemorrhage between groups.

CONCLUSION

One in ten patients thrombolysed for the treatment of AIS received MD. In a predominantly Hispanic population, those who received MD and WBD had similar rates of sICH, discharge disposition, and functional outcome (mRS) at discharge and at 90 days. Limitations include small sample size and attrition for the 90-day mRS.

European Stroke Organisation (ESO) guidelines on blood pressure management in acute ischaemic stroke and intracerebral haemorrhage

The optimal blood pressure (BP) management in acute ischaemic stroke (AIS) and acute intracerebral haemorrhage (ICH) remains controversial. These European Stroke Organisation (ESO) guidelines provide evidence-based recommendations to assist physicians in their clinical decisions regarding BP management in acute stroke.The guidelines were developed according to the ESO standard operating procedure and Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. The working group identified relevant clinical questions, performed systematic reviews and meta-analyses of the literature, assessed the quality of the available evidence, and made specific recommendations. Expert consensus statements were provided where insufficient evidence was available to provide recommendations based on the GRADE approach. Despite several large randomised-controlled clinical trials, quality of evidence is generally low due to inconsistent results of the effect of blood pressure lowering in AIS. We recommend early and modest blood pressure control (avoiding blood pressure levels >180/105 mm Hg) in AIS patients undergoing reperfusion therapies. There is more high-quality randomised evidence for BP lowering in acute ICH, where intensive blood pressure lowering is recommended rapidly after hospital presentation with the intent to improve recovery by reducing haematoma expansion. These guidelines provide further recommendations on blood pressure thresholds and for specific patient subgroups. There is ongoing uncertainty regarding the most appropriate blood pressure management in AIS and ICH. Future randomised-controlled clinical trials are needed to inform decision making on thresholds, timing and strategy of blood pressure lowering in different acute stroke patient subgroups.

Current approach to acute stroke management

There have been marked improvements in the management of stroke in Australia over the past two decades. The greatest benefit has accrued from public health measures including reduced smoking rates and treatment of hypertension and hypercholesterolaemia. Recent advances in recanalisation therapy offer the chance of recovery to a subset of people who have a stroke. For many patients, stroke remains an illness with a devastating impact on their quality of life. Reducing the burden of stroke requires intervention across the health system from primary prevention through diagnosis, acute treatment, rehabilitation and secondary prevention. In this review, we will cover the changes in the epidemiology of stroke, public health measures in primary prevention of stroke, and acute management and secondary prevention of ischaemic stroke and primary intracerebral haemorrhage.

Silver Jubilee of Stroke Thrombolysis With Alteplase: Evolution of the Therapeutic Window

In 1995, the results of a landmark clinical trial by National Institute of Neurological Disorders and Stroke (NINDS) made a paradigm shift in managing acute cerebral ischemic stroke (AIS) patients at critical care centers. The study demonstrated the efficacy of tissue-type plasminogen activator (tPA), alteplase in improving neurological and functional outcome in AIS patients when administered within 3 h of stroke onset. After about 12 years of efforts and the results of the ECASS-III trial, it was possible to expand the therapeutic window to 4.5 h, which still represents a major logistic issue, depriving many AIS patients from the benefits of tPA therapy. Constant efforts in this regards are directed toward either speeding up the patient recruitment for tPA therapy or expanding the current tPA window. Efficient protocols to reduce the door-to-needle time and advanced technologies like telestroke services and mobile stroke units are being deployed for early management of AIS patients. Studies have demonstrated benefit of thrombolysis guided by perfusion imaging in AIS patients at up to 9 h of stroke onset, signifying “tissue window.” Several promising pharmacological and non-pharmacological approaches are being explored to mitigate the adverse effects of delayed tPA therapy, thus hoping to further expand the current tPA therapeutic window without compromising safety. With accumulation of scientific data, stroke organizations across the world are amending/updating the clinical recommendations of tPA, the only US-FDA approved drug for managing AIS patients. Alteplase has been a part of our neurocritical care and we intend to celebrate its silver jubilee by dedicating this review article discussing its journey so far and possible future evolution.

Impact of estimated-weight-base dose of alteplase in acute stroke treatment on clinical outcome

Dosing of recombinant tissue plasminogen activator (rt-PA) for acute ischemic stroke treatment is often based on estimated body weight (BW) worldwide in routine clinical practice due to infeasible of accurate BW measurement. The aim of our study is to explore the impact of estimated BW when dosing rt-PA in acute ischemic stroke treatment on clinical outcome. Between January 2013 to May 2018, 126 acute ischemic stroke patients received intravenous rt-PA treatment based on estimated BW dosage were recruited. All patients had actual BW measured in ward after treatment. Based on the dosage of rt-PA given, patients were categorized into three groups, standard dose (0.8-1.0 mg/kg), overdose (>1.0 mg/kg), and underdose (<0.8 mg/kg). Among all 126 patients, 101 (80.2%) patients were treated with standard dose, 12 (9.5%) patients with overdose, and 13 (10.3%) patients with underdose of rt-PA respectively. There was no significant difference between demographic characteristics, pre-morbid risk factors, National Institutes of Health Stroke Scale (NIHSS) score at 24 h, NIHSS score at discharge, modified Rankin scale (mRS) within 0 to 2 in discharge or in 3 months after the event within the three groups. There was also no significant difference in hemorrhagic transformation and symptomatic intracranial hemorrhage (SICH). In conclusion, calculation of the dose of rt-PA based upon the estimated BW to treat acute ischemic stroke patients had no negative impact on the clinical outcome in our study.

IV tPA is associated with increase in rates of intracerebral hemorrhage and length of stay in patients with acute stroke treated with endovascular treatment within 4.5 hours: should we bypass IV tPA in large vessel occlusion?

BACKGROUND

Endovascular treatment (EVT) is a widely proved method to treat patients diagnosed with intracranial large vessel occlusions (LVOs); however, there has been controversy about the safety and efficacy of incorporating intravenous tissue plasminogen activator (IV tPA) as pretreatment for EVT.

OBJECTIVE

To compare the outcomes of all patients with LVO treated with IV tPA +EVT versus EVT alone within 4.5 hours of stroke onset.

METHODS

A prospectively collected endovascular database at a comprehensive stroke center between 2012 and 2019 was used to examine variables such as demographics, comorbid conditions, symptomatic/asymptomatic intracerebral hemorrhage (ICH), mortality rate, and good/poor outcomes as shown by the modified Thrombolysis in Cerebral Infarction score and modified Rankin Scale (mRS) assessment at discharge. The outcomes between patients receiving IV tPA+EVT on admission and patients who underwent EVT alone were compared.

RESULTS

Of 588 patients with acute ischemic stroke treated with EVT, a total of 189 met the criteria for the study (average age 70.44±12.90 years, 42.9% women). Analysis of 109 patients from the group receiving EVT+IV tPA (average age 68.17±14.28 years, 41.3% women), and 80 patients from the EVT alone group was performed (average age 73.54±9.84 years, 45.0% women). Four patients (5.0%) in the EVT alone group experienced symptomatic ICH versus 15 patients (13.8%) in the IV tPA+EVT group (p=0.0478); significant increases were also noted in the length of stay for patients treated with IV tPA (8.2 days vs 11.0 days; p=0.0056).

CONCLUSION

IV tPA in addition to EVT was associated with an increase in the rate of ICH in patients with LVO treated within 4.5 hours and in patients' length of stay. Further research is required to determine whether EVT treatment alone in patients with LVO treated within 4.5 hours is a more effective option.

Who may benefit from lower dosages of intravenous tissue plasminogen activator? Results from a cluster data analysis

Background

The risk of symptomatic intracranial haemorrhage (sICH) after thrombolysis is low but severe. Lower dose of alteplase may reduce the risk of sICH. We aim to identify subsets of patients who could benefit from lower dose of alteplase compared with standard dose.

Methods

Data from two observational registries were pooled together. A total of 3479 patients who had acute ischaemic stroke were entered into the interaction tree model. The response variable was the rate of sICH per the definition of the National Institute of Neurological Disorders and Stroke Study. Clinical improvement was measured by the National Institutes of Health Stroke Scale (NIHSS) and defined as NIHSS 0 or 1 or an improvement of more than 4 points (within 7 days or at discharge). Rare event logistic regression was performed to analyse the OR of safety outcome.

Results

To optimise the interaction effect between tissue plasminogen activator (tPA) dosage (standard/lower) and patient subgroups, three subgroups based on the severity of stroke were identified: (1) NIHSS ≤4, (2) NIHSS between 5 and 14, and (3) NIHSS ≥15. The estimated difference of OR of having sICH was 2.71 (95% CI 0.80 to 7.69, p=0.10) for mild, 0.13 (95% CI 0.02 to 0.68, p=0.01) for moderate, and 0.65 (95% CI 0.19 to 2.55, p=0.52) for severe, respectively. In addition, patients who had moderate stroke treated with lower dose had comparable efficacy outcome (OR 1.23, 95% CI 0.71 to 2.13, p=0.45).

Conclusion

Our analysis demonstrated that in patients who had moderate stroke, lower doses of alteplase are associated with significant sICH reduction and non-inferior performance in efficacy, compared with those in the standard dose group.

Trial registration number

The TIMS-China was a national prospective stroke registry on thrombolytic therapy using intravenous tPA in patients who had acute ischaemic stroke. The results were initially published in 2012 without a clinical trial registration number. The Shanghai Stroke Service System was registered at www.clinicaltrial.gov (NCT02735226).

Blood Pressure Management Following Acute Ischemic Stroke: A Review of Primary Literature

Elevated blood pressure is common in patients with acute ischemic stroke. While this may occur secondary to the body's own response to preserve cerebral blood flow, elevated blood pressure may also increase the risk of hemorrhagic transformation. Current guidelines recommend various blood pressure goals based upon multiple factors, including thresholds specific to certain treatment interventions. Despite these guidelines, there is limited evidence to support specific blood pressure targets, and variability in clinical practice is common. The purpose of this review was to discuss blood pressure management in adult patients with acute ischemic stroke, focusing on appropriate targets in the setting of alteplase administration, mechanical thrombectomy, and hemorrhagic transformation.

Thrombolysis related symptomatic intracranial hemorrhage in estimated versus measured body weight

BACKGROUND AND AIM

In acute ischemic stroke, under- or overestimation of body weight can lead to dosing errors of recombinant tissue plasminogen activator with consequent reduced efficacy or increased risk of hemorrhagic complications. Measurement of body weight is more accurate than estimation of body weight but potentially leads to longer door-to-needle times. Our aim was to assess if weight modality (estimation of body weight versus measurement of body weight) is associated with (i) symptomatic intracranial hemorrhage rate, (ii) clinical outcome, and (iii) door-to-needle times.

METHODS

Consecutive patients treated with intravenous thrombolysis between 2009 and 2016 from 14 hospitals were included. Baseline characteristics and outcome parameters were retrieved from medical records. We defined symptomatic intracranial hemorrhage according to the European Cooperative Acute Stroke Study (ECASS)-III definition and clinical outcome was assessed with the modified Rankin Scale. The association of weight modality and outcome parameters was estimated with regression analyses.

RESULTS

A total of 4801 patients were included. Five hospitals used measurement of body weight (n = 1753), six hospitals used estimation of body weight (n = 2325), and three hospitals (n = 723) changed from estimation of body weight to measurement of body weight during the study period. In 2048 of the patients (43%), measurement of body weight was used and in 2753 (57%), estimation of body weight. In the measurement of body weight group, an inbuilt weighing bed was used in 1094 patients (53%) and a patient lift scale in 954 patients (47%). In the estimation of body weight group, policy regarding estimation was similar. Estimation of body weight was not associated with increased symptomatic intracranial hemorrhage risk (adjusted odds ratio = 1.16; 95% confidence interval 0.83-1.62) or favorable outcome (adjusted odds ratio = 0.99; 95% confidence interval 0.82-1.21), but it was significantly associated with longer door-to-needle times compared to measurement of body weight using an inbuilt weighing bed (adjusted B = 3.57; 95% confidence interval 1.33-5.80) and shorter door-to-needle times compared to measurement of body weight using a patient lift scale (-3.96; 95% confidence interval -6.38 to -1.53).

CONCLUSION

We did not find evidence that weight modality (estimation of body weight versus measurement of body weight) to determine recombinant tissue plasminogen activator dose in intravenous thrombolysis eligible patients is associated with symptomatic intracranial hemorrhage or clinical outcome. We did find that estimation of body weight leads to longer door-to-needle times compared to measurement of body weight using an inbuilt weighing bed and to shorter door-to-needle times compared to measurement of body weight using a patient lift scale.

Management of Blood Pressure After Acute Ischemic Stroke

PURPOSE OF REVIEW

The present manuscript examines the significance of blood pressure elevation in patients with acute ischemic stroke, the physiologic principles worthy of consideration during its treatment, and the recent empirical evidence that should guide management protocols. It also provides a sound and practical approach to treatment along the time continuum, with particular relevance to reperfusion strategies.

RECENT FINDINGS

The existing evidence shows that both insufficient and excessive blood pressures are detrimental to the outcome of patients with acute ischemic stroke. This "U-shaped" relation, however, relates to measurements at the time of presentation, and clinical studies lack detail and specificity relative to differential measurements along the time continuum, particularly prior to and following reperfusion. Extrapolating from recent series, it is possible to construct treatment protocols balanced for effectiveness and safety. The management of blood pressure after acute ischemic stroke is an important, complex, and challenging aspect of care, requiring a thorough understanding of cerebrovascular physiology. Along the time continuum, the therapeutic priorities start with the preservation of penumbral tissue prior to reperfusion and then follow with the limitation of the damaging effects of excessive blood pressure readings after reperfusion, optimizing the chances of improved outcomes.

Fixed Dose IV rt-PA and Clinical Outcome in Ischemic Stroke Patients With Body Weight >100 kg: Pooled Data From 3 Randomized Clinical Trials

BACKGROUND AND PURPOSE

The ASA/AHA guidelines recommend a fixed dose of 90 mg of intravenous (IV) recombinant tissue plasminogen activator (rt-PA) for acute stroke patients weighing more than 100 kg. We aimed to determine if body weight >100 kg (and receiving <0.9 mg/kg dose) independently influence patient clinical outcomes following IV rt-PA treatment.

METHODS

We pooled data from IV rt-PA treatment arms from 3 randomized controlled clinical trials; NINDS IV rt-PA study, Interventional Management of Stroke 3 and ALIAS (part 1 and 2). Baseline characteristic, hospital course and 90-day mRS were compared between patients >100 kg and those ≤100 kg body weight. Multivariate logistic regression model was used to identify the independent effect of >100 kg body weight on favorable 90-day outcome (defined as mRS 0-2), the rate of symptomatic intracranial hemorrhage, and poor 90-day outcome (mRS 4-6).

RESULTS

Among 873 patients treated with IV rt-PA, a total of 105 (12%) subjects had body weight >100 kg. Compared with patients having ≤100 kg body weight, the rate of favorable outcome at 90 days was not significantly different among patients with >100 kg body weight (OR: 0.99; 95% CI: 0.91-1.01; p=0.91) , after adjusting for potential confounders. The ordinal analysis did not show any significant shift in the distribution of 90-day mRS score in patients with >100 kg body weight (OR, 0.93; 95% CI, 0.64-1.37; P = 0.74) CONCLUSIONS: There was no reduction in the rate of favorable outcome in patients with acute ischemic stroke with body weight >100 kg who received <0.9 mg/kg dose of IV rt-PA. Our results support the current recommendations in the ASA/AHA guidelines.

Different doses of tenecteplase vs alteplase in thrombolysis therapy of acute ischemic stroke: evidence from randomized controlled trials

Background

Recent studies showed inconsistent results of tenecteplase vs alteplase for acute ischemic stroke (AIS) with safety and efficacy.

Methods

A meta-analysis was performed to explore the value of tenecteplase and alteplase in AIS treatment. Medline, Embase, and Cochrane Library from January 2001 to April 2018 were searched for randomized controlled trials (RCTs) with tenecteplase vs alteplase for AIS.

Results

The primary outcomes were early neurological improvement at 24 h and functional outcome at 3 months. We pooled 1,390 patients from four RCTs. Tenecteplase showed a significant early neurological improvement (P=0.035) compared with alteplase. In addition, tenecteplase showed a neutral effect on excellent outcome (P=0.309), good functional outcome (P=0.275), and recanalization (P=0.3). No significant differences in safety outcomes were demonstrated. In subgroup analysis, 0.25 mg/kg dose of tenecteplase showed a significantly increased early neurological improvement (P<0.001). In serious stroke at baseline (National Institutes of Health Stroke Scale [NIHSS] >12) subgroup, tenecteplase showed a dramatic early neurological improvement (P=0.002) and low risks of any intracranial hemorrhage (ICH) (P=0.027).

Conclusion

Tenecteplase provided better early neurological improvement than alteplase. The 0.25 mg/kg dose of tenecteplase subgroup specially showed better early neurological improvement and lower any ICH tendency than that of alteplase. In addition, in serious stroke at baseline subgroup, tenecteplase showed a lower risk of any ICH.

Simultaneous acute cardio-cerebral infarction: is there a consensus for management?

Acute ischemic stroke (AIS) and acute myocardial infarction (AMI) are both life-threatening medical conditions with narrow therapeutic time-window that carry grave prognosis if not addressed promptly. The acute management of both condition is well documented in the literature, however the management of a simultaneous presentation of both AIS and AMI is unclear. A delayed intervention of one infarcted territory for the other may result in permanent irreversible morbidity or disability, and even death. In addition, the use of antiplatelet and anticoagulants that are inherently part of an AMI management may increase the risk for hemorrhagic conversion associated with intravenous thrombolysis used in AIS, and the use of a thrombolytic in AIS increases the risk of cardiac wall rupture in the setting of an AMI. Despite this ambiguity, there is no clear evidence-based guideline or clinical studies that have addressed the optimal management of this rare co-occurrence. This review paper examines the existing literature on the management of simultaneous acute cardio-cerebral infarction (CCI) and highlights the existing challenge to management.

Change in blood pressure variability in patients with acute ischemic stroke and its effect on early neurologic outcome

Background

How short-term blood pressure variability (BPV) is affected in the acute stage of ischemic stroke and whether BPV is associated with early neurologic outcomes remains unclear.

Methods

Patients who admitted for ischemic stroke within 24 h of symptom onset were consecutively identified between January 2010 and January 2015. BP profiles measured in real-time were summarized into short-term, 24-h time intervals, based on standard deviation (SD) and mean of systolic BP (SBP_SD) during the first 3 days. The primary outcome was daily assessment of early neurological deterioration (END). The associations between short-term SBP_SD values and the secular trend for primary outcome were examined.

Results

A total of 2,545 subjects (mean age, 67.1 ± 13.5 years old and median baseline National Institutes of Health Stroke Scale score, 3) arrived at the hospital an average of 6.1 ± 6.6 h after symptom onset. SBP_SD values at day 1 (SD#D1), SD#D2, and SD#D3 were 14.4 ± 5.0, 12.5 ± 4.5, and 12.2 ± 4.6 mmHg, respectively. Multivariable analyses showed that SD#D2 was independently associated with onset of END at day 2 (adjusted odds ratio, 1.08; 95% confidence interval, 1.03–1.13), and SD#D3 was independently associated with END#D3 (1.07, 1.01–1.14), with adjustments for predetermined covariates, SBP_mean, and interactions with daily SBP_SD.

Conclusion

Short-term BPV changed and stabilized from the first day of ischemic stroke. Daily high BPV may be associated with neurological deterioration independent of BPV on the previous day.

Prediction of thrombus resolution after intravenous thrombolysis assessed by CT-based thrombus imaging

The degree of thrombus resolution directly indicates the effectiveness of a thrombolytic drug. We investigated the degree of thrombus resolution and factors associated with thrombus resolution after intravenous (IV) recombinant tissue plasminogen activator (rt-PA) using thin-section noncontrast computed tomography (NCT). Thin-section NCTs were performed before and immediately after IV rt-PA infusion in acute stroke patients. The thrombus volume and Hounsfield unit were measured using three-dimensional imaging software. Immediate recanalisation was assessed immediately after IV rt-PA infusion using CT angiography. During a three-year study period, 130 patients were prospectively enrolled. On baseline thin-section NCT, no thrombi were found in 30 patients (23%). Among the 100 patients with confirmed thrombus, the median volume decreased by 20% on the follow-up NCT. The thrombus was completely resolved in 8%. Of note, an increase in thrombus volume was observed in 20 patients. Independent predictors of thrombus resolution were total rt-PA dose, thrombus location in the M2 segment of the middle cerebral artery, and time from baseline to follow-up NCT. Thrombus resolution increased by 9% per each 10-mg increase in rt-PA (p = 0.045). Immediate complete recanalisation was achieved in 12% of patients. Total dose of rt-PA was independently associated with complete recanalisation [odds ratio [OR] 4.52, 95% confidence interval [CI] 1.345–15.184) and good functional outcome at three months (modified Rankin scale score <3, OR 2.34, 95% CI 1.104–4.962). In conclusion, rt-PA dose was associated with the degree of thrombus resolution, immediate complete recanalisation, and good outcome at three months. CT-based thrombus imaging may be helpful in determining thrombolysis effectiveness.

Efficacy and safety of low dose alteplase for intravenous thrombolysis in Asian stroke patients: a meta-analysis

Whether low dose alteplase is comparable to standard dose in efficacy and safety for intravenous thrombolysis (IVT) in Asian stroke patients remains unverified. PubMed, EMBASE, and Cochrane Library Database from the beginning to June 30, 2017 were searched. IVT efficacy was measured by favorable outcome (modified Rankin Scale scores of 0–1) at 3 months, and safety measured by mortality within 3 months and symptomatic intracerebral hemorrhage (SICH). Pooled estimates were conducted using fixed- or random-effects model depending on heterogeneity. For SICH, studies were pooled separately according to different definitions. Twelve studies involving 7,905 participants were included. No association was found between alteplase dose and favorable outcome (OR = 0.94, 95% CI 0.78–1.14, P = 0.5; heterogeneity: P_hetero = 0.01, I² = 57.3%) and mortality (OR = 0.87, 95% CI 0.74–1.02, P = 0.08; P_hetero = 0.83, I² = 0) using random- and fixed-effects models, respectively. Low dose alteplase was associated with lower SICH as defined by the National Institute of Neurological Disorders and Stroke study (OR = 0.79, 95% CI 0.64–0.99, P = 0.04; P_hetero = 0.57, I² = 0) using fixed-effects model. Subgroup and sensitivity analysis could change the results significantly. Current limited evidence was insufficient to support the speculation that low dose alteplase was comparable to standard dose in thrombolytic efficacy and safety in Asian stroke patients.

Single Cell Immuno-Laser Microdissection Coupled to Label-Free Proteomics to Reveal the Proteotypes of Human Brain Cells After Ischemia

Cerebral ischemia entails rapid tissue damage in the affected brain area causing devastating neurological dysfunction. How each component of the neurovascular unit contributes or responds to the ischemic insult in the context of the human brain has not been solved yet. Thus, the analysis of the proteome is a straightforward approach to unraveling these cell proteotypes. In this study, post-mortem brain slices from ischemic stroke patients were obtained corresponding to infarcted (IC) and contralateral (CL) areas. By means of laser microdissection, neurons and blood brain barrier structures (BBB) were isolated and analyzed using label-free quantification. MS data are available via ProteomeXchange with identifier PXD003519. Ninety proteins were identified only in neurons, 260 proteins only in the BBB and 261 proteins in both cell types. Bioinformatics analyses revealed that repair processes, mainly related to synaptic plasticity, are outlined in microdissected neurons, with nonexclusive important functions found in the BBB. A total of 30 proteins showing p < 0.05 and fold-change> 2 between IC and CL areas were considered meaningful in this study: 13 in neurons, 14 in the BBB and 3 in both cell types. Twelve of these proteins were selected as candidates and analyzed by immunohistofluorescence in independent brains. The MS findings were completely verified for neuronal SAHH2 and SRSF1 whereas the presence in both cell types of GABT and EAA2 was only validated in neurons. In addition, SAHH2 showed its potential as a prognostic biomarker of neurological improvement when analyzed early in the plasma of ischemic stroke patients. Therefore, the quantitative proteomes of neurons and the BBB (or proteotypes) after human brain ischemia presented here contribute to increasing the knowledge regarding the molecular mechanisms of ischemic stroke pathology and highlight new proteins that might represent putative biomarkers of brain ischemia or therapeutic targets.

The Impact of Discrepancy between Measured versus Stated Weight on Hemorrhagic Transformation and Clinical Outcomes after Intravenous Alteplase Thrombolysis

BACKGROUND

An accurate measurement of patient weight is important in determining the dosage for intravenous alteplase thrombolysis. In most emergency rooms, however, weight is not measured. We investigated the difference between stated and measured weight and its effect on hemorrhagic transformation and clinical outcomes.

METHODS

We enrolled 128 consecutive patients who had hyperacute stroke and were treated by alteplase. Alteplase dose was calculated using the weight provided by patient or guardian/caregiver, and the actual weight was measured after administration. Patients were classified into 2 groups: overused group (stated weight >measured weight) and underused group (measured weight ≥stated weight). The prevalence of hemorrhagic transformation on follow-up, determined by gradient-recalled echo MRI or non-enhanced CT, was compared between the 2 groups. The predictors for hemorrhage with progression, defined as an increase in the National Institutes of Health Stroke Scale (NIHSS) by a value of 4 or more accompanied by hemorrhage, were determined using multivariable logistic regression analysis and included the overused or underused alteplase and baseline clinical and laboratory findings.

RESULTS

Sixty-six (51.6%) of 128 patients were in the underused group and 62 patients (48.4%) in the overused group. The median difference between the stated and measured weights was 1.5 (interquartile range 0.56-3.81) kg, with the largest difference being 25.6 kg. Although there were no significant difference in baseline clinical and laboratory findings between the 2 groups, the overused group showed a significantly higher prevalence of hemorrhagic transformation (p = 0.012) and hemorrhage with progression (p = 0.025). The multivariable logistic regression analysis demonstrated that overused alteplase (OR 7.26; 95% CI 1.24-42.45; p = 0.028), baseline glucose (>144 mg/dL; OR 5.03; 95% CI 1.00-25.26; p = 0.050), and initial NIHSS (OR 1.13 per 1-point NIHSS increase; 95% CI 1.00-1.27; p = 0.047) in model 1 that use alteplase overdose as a categorical variable and overused alteplase (OR 1.67 1-mg increase; 95% CI 1.05-2.66; p = 0.027) in model 2 that use an overused alteplase dose as numerical variable were significant predictors for hemorrhage with progression.

CONCLUSION

More alteplase usage than actual weight led to higher hemorrhagic transformation. As one of the predictors for clinical deterioration, it is important to administrate alteplase based on an accurately measured weight.

The need for a population-based, dose optimization study for recombinant tissue plasminogen activator in acute ischemic stroke: A study from a tertiary care teaching hospital from South India

Context:

The guideline recommended dose of intravenous (i.v) recombinant tissue-type plasminogen activator (rt-PA) for acute ischemic stroke is 0.9 mg/kg in the European and American populations. In Asiatic population, some studies have shown that a lower dose of i.v rt-PA is equally efficacious.

Aims:

To assess if there is a need for a dose optimization for i.v rt-PA study among Indians.

Setting and Design:

A prospective, observational database of acute stroke cases that presented to a tertiary care institute over a period of 1 year was made.

Methods:

The data procured using a prestructured elaborate pro forma. Based on the dose of rt-PA received, the individuals were divided into three groups; Group 1 (0.6–0.7 mg/kg), Group 2 (0.7–0.8 mg/kg), and Group 3 (0.8–0.9 mg/kg). Improvement was assessed in each group and between the thrombolysed and nonthrombolysed individuals.

Statistical Analysis Used:

The nonparametric Mann–Whitney U-test (Wilcoxon rank-sum test) was applied for assessing improvement of National Institutes of Health Stroke Scale score with significance level of α < 0.05 (P < 0.012) and compliance level at 95%.

Results:

Between the thrombolysed (n = 46) and nonthrombolysed (n = 113) group, there was a statistically significant neurological improvement in the thrombolysed group. Clinical improvement was noted in 75%, 85.7%, and 66.7% of individuals receiving rt-PA in Groups 1, 2, and 3, respectively. Four out of the five who developed a clinically significant intracranial hemorrhage were thrombolysed at a dose of 0.8–0.9 mg/kg rt-PA (Group 3).

Conclusion:

There is a need for a properly randomized, dose optimization study of i.v rt-PA in the Indian subcontinent.

Neurorestoration after stroke

Recent advancements in stem cell biology and neuromodulation have ushered in a battery of new neurorestorative therapies for ischemic stroke. While the understanding of stroke pathophysiology has matured, the ability to restore patients' quality of life remains inadequate. New therapeutic approaches, including cell transplantation and neurostimulation, focus on reestablishing the circuits disrupted by ischemia through multidimensional mechanisms to improve neuroplasticity and remodeling. The authors provide a broad overview of stroke pathophysiology and existing therapies to highlight the scientific and clinical implications of neurorestorative therapies for stroke.

Prosthetic Valve Thrombosis in the Acute Phase of the Stroke: Relevance of Detection and Follow-Up

BACKGROUND

Stroke may be the first symptom of prosthetic valve thrombosis (PVT); therefore, rapid diagnosis and therapy are crucial. We aimed to evaluate the prevalence, main predictors, and long-term clinical evolution of patients with PVT in the acute phase of stroke.

METHODS

We studied consecutive acute ischemic stroke patients with prosthetic heart valves who underwent emergent transesophageal echocardiography (TEE) during a 5-year period. Two groups were defined depending on the presence of PVT (PVT or non-PVT groups). Baseline characteristics, TEE findings, and international normalized ratios (INRs) at the stroke event were registered. Follow-up visits and TEE control examinations were performed.

RESULTS

Sixty-seven patients were registered. TEE was performed within the first week in 85% of patients (n = 57). PVT was diagnosed in 41.8% of cases (n = 28). Clinical severity and baseline INR level showed no differences when the PVT and non-PVT groups were compared. The presence of PVT was associated with the mitral valve location as compared with the aortic valve location (75% versus 25%, P = .003), the presence of spontaneous echocontrast (64.3% versus 35.9%, P = .022), and low ejection fraction (66.7% versus 32.7%, P = .019). The PVT group showed a trend toward higher percentage of recurrence (10.7% versus 2.5%, P = .102) in the follow up period (mean follow-up 25 months).

CONCLUSIONS

The detection of PVT in the acute stroke phase was relevant, as the stroke recurrence rate was considerable. Therefore, all patients with prosthetic heart valve should undergo emergent TEE.

Stroke outcomes are worse with larger leukoaraiosis volumes

Leukoaraiosis or white matter hyperintensities are frequently observed on magnetic resonance imaging of stroke patients. We investigated how white matter hyperintensity volumes affect stroke outcomes, generally and by subtype. In total, 5035 acute ischaemic stroke patients were enrolled. Strokes were classified as large artery atherosclerosis, small vessel occlusion, or cardioembolism. White matter hyperintensity volumes were stratified into quintiles. Mean age (± standard deviation) was 66.3 ± 12.8, 59.6% male. Median (interquartile range) modified Rankin Scale score was 2 (1-3) at discharge and 1 (0-3) at 3 months; 16.5% experienced early neurological deterioration, and 3.3% recurrent stroke. The Cochran-Mantel-Haenszel test with adjustment for age, stroke severity, sex, and thrombolysis status showed that the distributions of 3-month modified Rankin Scale scores differed across white matter hyperintensity quintiles (P < 0.001). Multiple ordinal logistic regression analysis showed that higher white matter hyperintensity quintiles were independently associated with worse 3-month modified Rankin Scale scores; adjusted odds ratios (95% confidence interval) for the second to fifth quintiles versus the first quintile were 1.29 (1.10-1.52), 1.40 (1.18-1.66), 1.69 (1.42-2.02) and 2.03 (1.69-2.43), respectively. For large artery atherosclerosis (39.0%), outcomes varied by white matter hyperintensity volume (P = 0.01, Cochran-Mantel-Haenszel test), and the upper three white matter hyperintensity quintiles (versus the first quintile) had worse 3-month modified Rankin Scale scores; adjusted odds ratios were 1.45 (1.10-1.90), 1.86 (1.41-2.47), and 1.89 (1.41-2.54), respectively. Patients with large artery atherosclerosis were vulnerable to early neurological deterioration (19.4%), and the top two white matter hyperintensity quintiles were more vulnerable still: 23.5% and 22.3%. Moreover, higher white matter hyperintensities were associated with poor modified Rankin Scale improvement: adjusted odds ratios for the upper two quintiles versus the first quintile were 0.66 (0.47-0.94) and 0.62 (0.43-0.89), respectively. For small vessel occlusion (17.8%), outcomes tended to vary by white matter hyperintensitiy volume (P = 0.10, Cochran-Mantel-Haenszel test), and the highest quintile was associated with worse 3-month modified Rankin Scale scores: adjusted odds ratio for the fifth quintile versus first quintile, 1.98 (1.23-3.18). In this subtype, worse white matter hyperintensities were associated with worse National Institute of Health Stroke Scale scores at presentation. For cardioembolism (20.6%), outcomes did not vary significantly by white matter hyperintensity volume (P = 0.19, Cochran-Mantel-Haenszel test); however, the adjusted odds ratio for the highest versus lowest quintiles was 1.62 (1.09-2.40). Regardless of stroke subtype, white matter hyperintensities were not associated with stroke recurrence within 3 months of follow-up. In conclusion, white matter hyperintensity volume independently correlates with stroke outcomes in acute ischaemic stroke. There are some suggestions that stroke outcomes may be affected by leukoaraiosis differentially depending on stroke subtypes, to be confirmed in future investigations.

Obesity and stroke: Can we translate from rodents to patients?

Obesity is a risk factor for stroke and is consequently one of the most common co-morbidities found in patients. There is therefore an identified need to model co-morbidities preclinically to allow better translation from bench to bedside. In preclinical studies, both diet-induced and genetically obese rodents have worse stroke outcome, characterised by increased ischaemic damage and an altered inflammatory response. However, clinical studies have reported an 'obesity paradox' in stroke, characterised by reduced mortality and morbidity in obese patients. We discuss the potential reasons why the preclinical and clinical studies may not agree, and review the mechanisms identified in preclinical studies through which obesity may affects stroke outcome. We suggest inflammation plays a central role in this relationship, as obesity features increases in inflammatory mediators such as C-reactive protein and interleukin-6, and chronic inflammation has been linked to worse stroke risk and outcome.

Low-dose intravenous tissue plasminogen activator for acute ischaemic stroke: an alternative or a new standard?

BACKGROUND

With the recent publication of a large clinical trial on the use of a lower dose of intravenous (IV) tissue plasminogen activator (tPA) for acute ischaemic stroke (AIS), the concept of using a different dose has been debated. We intend to review the literature on using a lower dose of IV tPA and gain a better understanding of the impact of different IV doses on the treatment of patients with AIS.

METHODS

A comprehensive literature search of the related topics in PubMed, EMBASE, Web of Science and MEDLINE was carried out. Key words used include low dose IV tPA, thrombolysis, Alteplace and tPA for AIS. Findings were tabulated according to the size of the cohort studied, outcome, adverse event and level of evidence. The results of all studies using lower doses were analysed for efficacy and adverse events.

RESULTS

From 1992 to 2016, there were 23 trials that included 10 950 patients published on the use of lower doses of IV tPA for AIS. Doses ranged from 0.5, 0.6, 0.75 to 0.85 mg/kg. Most were observational, retrospective and registry studies. One was a prospective open-label randomised controlled trial. 13 trials combined lower doses of IV tPA with a glycoprotein IIb/IIIa inhibitor or thrombectomy. Patients treated with lower doses of IV tPA showed a trend of lower rate of symptomatic intracranial haemorrhage and mortality at 3 months but slightly more disability.

CONCLUSIONS

Lower doses of IV tPA showed less haemorrhagic events but were not more effective compared with the standard dose. The optimal low dose of IV tPA remains unclear. Patients with AIS with a high risk of developing sypmtomatic intracranial haemorrhage might benefit from lower dose IV tPA, such as 0.6 mg/kg.