Fibrinogen depletion and intracerebral hemorrhage after thrombolysis for ischemic stroke: a meta-analysis

A multitrait genetic study of hemostatic factors and hemorrhagic transformation after stroke treatment

BACKGROUND

Thrombolytic recombinant tissue plasminogen activator (r-tPA) treatment is the only pharmacologic intervention available in the ischemic stroke acute phase. This treatment is associated with an increased risk of intracerebral hemorrhages, known as hemorrhagic transformations (HTs), which worsen the patient's prognosis.

OBJECTIVES

To investigate the association between genetically determined natural hemostatic factors' levels and increased risk of HT after r-tPA treatment.

METHODS

Using data from genome-wide association studies on the risk of HT after r-tPA treatment and data on 7 hemostatic factors (factor [F]VII, FVIII, von Willebrand factor [VWF], FXI, fibrinogen, plasminogen activator inhibitor-1, and tissue plasminogen activator), we performed local and global genetic correlation estimation multitrait analyses and colocalization and 2-sample Mendelian randomization analyses between hemostatic factors and HT.

RESULTS

Local correlations identified a genomic region on chromosome 16 with shared covariance: fibrinogen-HT, P = 2.45 × 10-11. Multitrait analysis between fibrinogen-HT revealed 3 loci that simultaneously regulate circulating levels of fibrinogen and risk of HT: rs56026866 (PLXND1), P = 8.80 × 10-10; rs1421067 (CHD9), P = 1.81 × 10-14; and rs34780449, near ROBO1 gene, P = 1.64 × 10-8. Multitrait analysis between VWF-HT showed a novel common association regulating VWF and risk of HT after r-tPA at rs10942300 (ZNF366), P = 1.81 × 10-14. Mendelian randomization analysis did not find significant causal associations, although a nominal association was observed for FXI-HT (inverse-variance weighted estimate [SE], 0.07 [-0.29 to 0.00]; odds ratio, 0.87; 95% CI, 0.75-1.00; raw P = .05).

CONCLUSION

We identified 4 shared loci between hemostatic factors and HT after r-tPA treatment, suggesting common regulatory mechanisms between fibrinogen and VWF levels and HT. Further research to determine a possible mediating effect of fibrinogen on HT risk is needed.

Safety and Efficacy of Dual Thrombolytic Therapy With Mutant Prourokinase and Small Bolus Alteplase for Ischemic Stroke: A Randomized Clinical Trial

Importance

Dual thrombolytic treatment with small bolus alteplase and mutant prourokinase has the potential to be a safer and more efficacious treatment for ischemic stroke than alteplase alone because mutant prourokinase is designed to act only on degraded fibrin without affecting circulating fibrinogen.

Objective

To assess the safety and efficacy of this dual thrombolytic treatment compared with alteplase.

Design, Setting, and Participants

This controlled, open-label randomized clinical trial with a blinded end point was conducted from August 10, 2019, to March 26, 2022, with a total follow-up of 30 days. Adult patients with ischemic stroke from 4 stroke centers in the Netherlands were enrolled.

Interventions

Patients were randomized (1:1) to receive a bolus of 5 mg of intravenous alteplase and 40 mg of an intravenous infusion of mutant prourokinase (intervention) or usual care with 0.9 mg/kg of intravenous alteplase (control).

Main Outcomes and Measures

The primary outcome was any intracranial hemorrhage (ICH) on neuroimaging at 24 hours. Secondary outcomes included functional outcome at 30 days, symptomatic ICH, and fibrinogen levels within 24 hours. Analyses were by intention to treat. Treatment effects were adjusted for baseline prognostic factors.

Results

A total of 268 patients were randomized, and 238 (median [IQR] age, 69 [59-77] years; 147 [61.8%] male) provided deferred consent and were included in the intention-to-treat population (121 in the intervention group and 117 in the control group). The median baseline score on the National Institutes of Health Stroke Scale was 3 (IQR, 2-5). Any ICH occurred in 16 of 121 patients (13.2%) in the intervention group and 16 of 117 patients (13.7%) in the control group (adjusted odds ratio, 0.98; 95% CI, 0.46-2.12). Mutant prourokinase led to a nonsignificant shift toward better modified Rankin Scale scores (adjusted common odds ratio, 1.16; 95% CI, 0.74-1.84). Symptomatic ICH occurred in none of the patients in the intervention group and 3 of 117 patients (2.6%) in the control group. Plasma fibrinogen levels at 1 hour remained constant in the intervention group but decreased in the control group (β = 65 mg/dL; 95% CI, 26-105 mg/dL).

Conclusions and Relevance

In this trial, dual thrombolytic treatment with small bolus alteplase and mutant prourokinase was found to be safe and did not result in fibrinogen depletion. Further evaluation of thrombolytic treatment with mutant prourokinase in larger trials to improve outcomes in patients with larger ischemic strokes is needed. Overall, in patients with minor ischemic stroke who met indications for treatment with intravenous thrombolytics but were not eligible for treatment with endovascular therapy, dual thrombolytic therapy with intravenous mutant prourokinase was not superior to treatment with intravenous alteplase alone.

Trial Registration

ClinicalTrials.gov Identifier: NCT04256473.

Hepatocyte growth factor-modified hair follicle stem cells ameliorate cerebral ischemia/reperfusion injury in rats

BACKGROUND

Hair follicle stem cells (HFSCs) are considered as a promising cell type in the stem cell transplantation treatment of neurological diseases because of their rich sources, easy access, and the same ectoderm source as the nervous system. Hepatocyte growth factor (HGF) is a pleiotropic cytokine that shows neuroprotective function in ischemic stroke. Here we assessed the therapeutic effects of HFSCs on ischemic stroke injury and the synthetic effect of HGF along with HFSCs.

METHODS

Rat HFSCs were intravenously transplanted into a middle cerebral artery ischemia/reperfusion (I/R) rat model. Neurological scoring and TTC staining were performed to assess the benefits of HFSC transplantation. Inflammatory cytokines, blood-brain barrier integrity and angiogenesis within penumbra were estimated by Western blot and immunohistochemistry. The differentiation of HFSCs was detected by immunofluorescence method 2 weeks after transplantation.

RESULTS

HFSC transplantation could significantly inhibit the activation of microglia, improve the integrity of blood-brain barrier and reduce brain edema. Moreover, the number of surviving neurons and microvessels density in the penumbra were upregulated by HFSC transplantation, leading to better neurological score. The combination of HFSCs and HGF could significantly improve the therapeutic benefit.

CONCLUSION

Our results indicate for the first time that HGF modified HFSCs can reduce I/R injury and promote the neurological recovery by inhibiting inflammatory response, protecting blood-brain barrier and promoting angiogenesis.

Percutaneous treatment options for acute pulmonary embolism: a clinical consensus statement by the ESC Working Group on Pulmonary Circulation and Right Ventricular Function and the European Association of Percutaneous Cardiovascular Interventions

There is a growing clinical and scientific interest in catheter-directed therapy (CDT) of acute pulmonary embolism (PE). Currently, CDT should be considered for patients with high-risk PE, in whom thrombolysis is contraindicated or has failed. Also, CDT is a treatment option for initially stable patients in whom anticoagulant treatment fails, i.e., those who experience haemodynamic deterioration despite adequately dosed anticoagulation. However, the definition of treatment failure (primary reperfusion therapy or anticoagulation alone) remains an important area of uncertainty. Moreover, several techniques for CDT are available without evidence supporting one over the other, and variation in practice with regard to periprocedural anticoagulation is considerable. The aim of this position paper is to describe the currently available CDT approaches in PE patients and to standardise patient selection, the timing and technique of the procedure itself as well as anticoagulation regimens during CDT. We discuss several clinical scenarios of the clinical evaluation of the "efficacy" of thrombolysis and anticoagulation, including treatment failure with haemodynamic deterioration and treatment failure based on a lack of improvement. This clinical consensus statement serves as a practical guide for CDT, complementary to the formal guidelines.

Safety and efficacy of low-dose rt-PA with tirofiban to treat acute non-cardiogenic stroke: a single-center randomized controlled study

BACKGROUND AND PURPOSE

The recanalization rate after intravenous thrombolysis (IVT) is not enough and there is still the possibility of re-occlusion. We aim to investigate the effectiveness and safety of infusing tirofiban after IVT.

METHODS

We performed a prospective controlled study of 60 patients with acute non-cardiogenic ischemic stroke who were hospitalized in Yantai Yuhuangding Hospital from January 2018 to December 2019. The patients were divided into 2 groups: those who received tirofiban for 24 h after IVT (rt-PA + T group) and those who did not receive postprocedural intravenous tirofiban (rt-PA group). The rt-PA + T group received low-dose rt-PA (0.6 mg/kg). The rt-PA group received standard dose rt-PA (0.9 mg/kg). The main outcome measure were safety, included the symptomatic intracranial hemorrhage (sICH), any ICH, severe systemic bleeding, and mortality. The secondary outcome measure is curative efficacy which were evaluated by the 7d-NIHSS score and functional outcomes at 90 days. During hospitalization, the deterioration of neurological function was recorded.

RESULTS

All patients completed the follow-up with complete data, there were 30 patients in each of groups. The general characteristics between the two group patients had no statistically significant differences. Compared with the rt-PA + T group and the rt-PA group, in terms of safety, the rates of the sICH, severe systemic bleeding, and mortality in both groups were 0, and there was no statistically significant difference in the rates of any ICH between the two groups (10.0% vs. 3.3%, P = 0.306). In terms of efficacy, the rate of the early neurological deterioration events (END) was no statistical significance (0 vs. 6.6%, P = 0.246). There was no significant difference in the NIHSS score between the two groups before the IVT, and also at 24 h, however, the 7d-NIHSS score was lower in the rt-PA + T group compared with the rt-PA group (2.33 ± 1.85 vs. 4.80 ± 4.02, P = 0.004). At 90 days, 83.3% of patients in the rt-PA + T group had favorable functional outcomes compared with 60.0% of patients in the rt-PA group (P = 0.045).

CONCLUSIONS

Low-dose rt-PA combined with tirofiban in acute non-cardiogenic ischemic stroke did not increase the risk of ICH, and mortality, and it was associated with neurological improvement.

TRIAL REGISTRATION

The trial has been registered at the ChiCTR and identified as ChiCTR1800014666 (28/01/2018).