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Thrombolysis and embolectomy in treatment of acute stroke as a bridge to open-heart resection of giant cardiac myxoma: A case report

BACKGROUND

Cardiac embolism is a common cause of ischemic stroke in young adults. Neurological complications associated with atrial myxoma most frequently include cerebral infarct due to embolus. Early complete resection of giant cardiac myxoma is the key to its treatment and prevention of stroke recurrence.

CASE SUMMARY

A 42-year-old, previously healthy woman was admitted to the hospital with sudden-onset inability to speak and right-sided hemiplegia. While sweeping the floor 2 h prior to hospital admission, the patient developed sudden inability to express herself or understand what others were saying, accompanied by dyskinesia of the right limb, inability to walk or hold objects, and involuntary choreiform movements of the left upper limb. The patient was diagnosed with cerebral embolism and cardiac myxoma, complicated by left middle cerebral artery occlusion. The acute stroke was treated with intravenous thrombolytic therapy and arterial embolectomy as a bridging therapy to open resection of left atrial cardiac myxoma. The patient condition improved remarkably following initial thrombolysis and embolectomy and subsequently underwent emergency open resection of the atrial cardiac myxoma. She had no recurrence during 1-year follow-up.

CONCLUSION

Strong consideration should be given to urgent intravenous thrombolysis (rt-PA, alteplase) in young adult stroke patients at the time of hospital admission. The present case demonstrated a highly successful outcome that combined thrombolysis and arterial embolus retrieval as a bridge to early complete resection of a giant cardiac myxoma for both stroke treatment and recurrence prevention.

Two cases of successful recanalization for acute cerebral artery embolism during perioperative period of radiofrequency ablation for atrial fibrillation

To explore the strategy of acute cerebral artery embolism after radiofrequency catheter ablation (RFA) for atrial fibrillation (AF). Reporting two cases with acute cerebral infarction after RFA for AF. Two patients were both with AF, and intracardiac thrombus was excluded through transesophageal echocardiogram (TEE) before procedure. Approach of ablation: circumferential pulmonary vein ablation in left atrium to isolate pulmonary vein plus linear ablation in the top and bottom of left atrium (BOX procedure). They both received Dabigatran Etexilate 110 mg twice daily, starting 6 hr after ablation. Symptoms of major stroke appeared 30 hr after ablation in Case 1. Occlusion was detected in M1 segment of the left middle cerebral artery by MRI 2 hr after symptoms onset. Intravenous thrombolysis was given immediately. In Case 2, the patient presented symptoms of major stroke 34 hr after ablation and occlusion in the basilar artery was confirmed by MRI 4.5 hr after symptoms onset. Although it was beyond the thrombolysis time window, mechanical thrombectomy was taken 7 hr after the symptoms onset. The culprit artery was successfully revascularized in both cases. In Case 1, NIHSS score was reduced from 8 (before thrombolysis) to 0 (24 hr after thrombolysis). In Case 2, NIHSS score decreased from 18 (before embolectomy) to 3 (24 hr after embolectomy). Both of the patients live a normal life without brain function impairment and hemorrhage until the last follow‐up. Timely recanalization could attained a good cure effect when acute stoke was happened after RFA for AF.

Efficacy of Solitaire Stent Arterial Embolectomy in Treating Acute Cardiogenic Cerebral Embolism in 17 Patients

Background

Thrombolysis with rtPA is the only accepted drug therapy for acute ischemic stroke. Since acute cerebral stroke is so pervasive, newly developed recanalization methods have the potential for wide-ranging impacts on patient health and safety. We explored the efficacy and safety of Solitaire stent arterial embolectomy in the treatment of acute cardiogenic cerebral embolism.

Material/Methods

Between October 2012 and June 2015, 17 patients underwent Solitaire stent arterial embolectomy, either alone or in combination with rtPA intravenous thrombolysis, to treat acute cardiogenic cerebral embolism. Sheath placement time, vascular recanalization time, number of embolectomy attempts, and IV rtPA dose and time were recorded. Success and safety of the recanalization procedure, as well as clinical outcomes, were assessed. These results were compared to 16 control patients who were treated using only rtPA IV thrombolysis.

Results

Full recanalization of the occluded arteries was achieved in 15 (88.2%) of the Solitaire stent patients. NIH Stroke Scale scores of embolectomy patients improved by an average of 12.59±8.24 points between admission and discharge, compared to 5.56±5.96 in the control group (P<0.05). Glasgow Coma Score improvement between admission and discharge was also significantly higher in the embolectomy group (P<0.05). There was no significant difference in symptomatic intracerebral hemorrhage, high perfusion encephalopathy, incidence of hernia, or mortality between the 2 groups (P>0.05).

Conclusions

Solitaire stent embolectomy is a safe and effective alternative to simple venous thrombolytic therapy, and it can significantly improve short-term neurological function and long-term prognosis in acute cardiogenic cerebral embolism.

Machine learning for outcome prediction of acute ischemic stroke post intra-arterial therapy

Introduction

Stroke is a major cause of death and disability. Accurately predicting stroke outcome from a set of predictive variables may identify high-risk patients and guide treatment approaches, leading to decreased morbidity. Logistic regression models allow for the identification and validation of predictive variables. However, advanced machine learning algorithms offer an alternative, in particular, for large-scale multi-institutional data, with the advantage of easily incorporating newly available data to improve prediction performance. Our aim was to design and compare different machine learning methods, capable of predicting the outcome of endovascular intervention in acute anterior circulation ischaemic stroke.

Method

We conducted a retrospective study of a prospectively collected database of acute ischaemic stroke treated by endovascular intervention. Using SPSS®, MATLAB®, and Rapidminer®, classical statistics as well as artificial neural network and support vector algorithms were applied to design a supervised machine capable of classifying these predictors into potential good and poor outcomes. These algorithms were trained, validated and tested using randomly divided data.

Results

We included 107 consecutive acute anterior circulation ischaemic stroke patients treated by endovascular technique. Sixty-six were male and the mean age of 65.3. All the available demographic, procedural and clinical factors were included into the models. The final confusion matrix of the neural network, demonstrated an overall congruency of ∼80% between the target and output classes, with favourable receiving operative characteristics. However, after optimisation, the support vector machine had a relatively better performance, with a root mean squared error of 2.064 (SD: ±0.408).

Discussion

We showed promising accuracy of outcome prediction, using supervised machine learning algorithms, with potential for incorporation of larger multicenter datasets, likely further improving prediction. Finally, we propose that a robust machine learning system can potentially optimise the selection process for endovascular versus medical treatment in the management of acute stroke.

Intra-arterial treatment methods in acute stroke therapy

Acute revascularization is associated with improved outcomes in ischemic stroke patients. It is unclear which method of intra-arterial intervention, if any, is ideal. Promising approaches in acute stroke treatment are likely a combination of intravenous and endovascular revascularization efforts, combining early treatment initiation with direct clot manipulation and/or PTA/stenting. In this review, we will discuss available thrombolytic therapies and endovascular recanalization techniques, beginning with chemical thrombolytic agents, followed by mechanical devices, and a review of ongoing trials. Further randomized studies comparing medical therapy, intravenous and endovascular treatments are essential, and their implementation will require the wide support and enthusiasm from the neurologic, neuroradiologic, and neurosurgical stroke communities.

Successful recovery from carotid terminus occlusion after mechanical embolectomy in a fully anticoagulated patient

CASE DESCRIPTION

We describe a case of the patient with multiple contraindications for thrombolysis who underwent successful mechanical embolectomy for occlusion of the right carotid terminus. Her pre-procedural NIHSS was 16.

DISCUSSION

The patient demonstrated remarkable recovery within an hour of the procedure, and this clinical improvement was sustained at followup.

RESULTS

This case illustrates that mechanical embolectomy is a safe and potentially very effective intervention to treat major intracranial vessel occlusions in patients with multiple contraindications for thrombolysis.

The Interventional Management of Stroke (IMS) II Study

BACKGROUND AND PURPOSE

The purpose of this study was to further investigate the feasibility and safety of a combined intravenous and intra-arterial approach to recanalization for ischemic stroke.

METHODS

Subjects, ages 18 to 80, with a baseline NIHSS > or =10 had intravenous recombinant tissue plasminogen activator (rt-PA) started (0.6 mg/kg over 30 minutes) within 3 hours of onset. For subjects with an arterial occlusion at angiography, additional rt-PA was administered via the EKOS micro-infusion catheter or a standard microcatheter at the site of the thrombus up to a total dose of 22 mg over 2 hours of infusion or until thrombolysis.

RESULTS

The 81 subjects had a median baseline NIHSS score of 19. The median time to initiation of intravenous rt-PA was 142 minutes as compared with 108 minutes for placebo and 90 minutes for rt-PA-treated subjects in the NINDS rt-PA Stroke Trial (P<0.0001). The 3-month mortality in IMS II subjects was 16% as compared with the mortality of placebo (24%) and rt-PA-treated subjects (21%) in the NINDS rt-PA Stroke Trial. The rate of symptomatic intracerebral hemorrhage in IMS II subjects (9.9%) was not significantly different than that for rt-PA treated subjects in the NINDS t-PA Stroke Trial (6.6%). IMS II subjects had significantly better outcomes at 3 months than NINDS placebo-treated subjects for all end points (OR > or =2.7) and better outcomes than NINDS rt-PA-treated subjects as measured by the Barthel Index and Global Test Statistic.

CONCLUSIONS

A randomized trial of standard intravenous rt-PA as compared with a combined intravenous and intra-arterial approach is warranted and has begun.

Endovascular reperfusion therapy in acute ischaemic stroke

OBJECTIVES

Endovascular reperfusion therapy in acute ischaemic stroke comprises a number of pharmacological and mechanical procedures. Mechanical embolectomy offers the promise of efficacious treatment for patients in whom pharmacological thrombolysis is contraindicated or might be ineffective. The purpose of this review is to outline endovascular reperfusion therapy in acute ischaemic stroke with focus on mechanical embolectomy.

MATERIALS & METHODS

Data on endovascular reperfusion therapy were acquired through searches in MEDLINE 1990-2006 by cross referencing relevant key words.

RESULTS

Mechanical embolectomy works well on large-volume proximal occlusions for which there was previously no effective treatment. Early safety trials are promising, efficacy in terms of recanalisation is substantial, and both safety and efficacy is expected to improve with further advances in technology.

CONCLUSIONS

Intravenous thrombolysis with tPA revolutionised acute stroke treatment a decade ago. Endovascular reperfusion therapy now offers the promise of a second revolution, expanding the number of patients eligible and the time window open for specific stroke treatment.

Technology Insight: recanalization with drugs and devices during acute ischemic stroke

Revascularization therapy is pivotal to saving ischemic brain from infarction. Two major randomized trials of intravenous thrombolytic therapy have established clear clinical benefit, especially for strokes caused by small-vessel occlusion. Ischemic stroke caused by large-vessel intracranial occlusion carries higher morbidity, however, and intravenous thrombolytics are less capable of opening these large vessels. This observation makes a case for delivering thrombolytics directly into the clot, or simply removing the clot mechanically. Intra-arterial thrombolytic drugs have been shown to be effective for treating middle cerebral artery occlusions in a major randomized trial. In the past 2 years, a family of mechanical thrombectomy catheters designed to remove rather than dissolve the offending clot has received FDA clearance. Such devices offer alternative therapy to patients who cannot receive thrombolytics, and can also be used in combination with thrombolytics to safely restore cerebral perfusion. Mechanical techniques have not been directly compared with intra-arterial thrombolytic strategies, but these devices might be superior to thrombolytics within vessels with particularly high clot burden, such as the carotid terminus and the basilar artery. Comprehensive stroke centers are currently available in major metropolitan areas to treat stroke via intra-arterial means, and are likely to become 'hubs' to 'spoke' hospitals that are credentialed as primary stroke centers. This design will allow any patient timely access to state-of-the-art stroke treatment tailored to their needs.

Acute endovascular stroke therapy

A decade after the US Food and Drug Administration (FDA) approved intravenous tissue plasminogen activator for treatment of acute ischemic stroke, the public health impact of this treatment on stroke outcome remains limited. The extremely small time window for treatment and very low recanalization rates in large artery strokes are its major shortcomings. Endovascular therapies for the treatment of acute stroke have rapidly evolved during this time period and may overcome these limitations. FDA approval of the Mechanical Embolus Removal in Cerebral Ischemia (MERCI) concentric retriever in August 2004 for the treatment of occluded brain arteries has spurred trials of newer devices for mechanical thrombolysis in acute stroke. At present, there are two major National Institutes of Health-sponsored randomized controlled trials testing endovascular treatments in acute stroke. In this article, we provide an experience-guided review of the current approach to the endovascular treatment of acute ischemic stroke and current evidence for various strategies. We first emphasize the key aspects of patient selection, including the increasingly central role of perfusion/diffusion imaging. The technical aspects of chemical, mechanical, ultrasound-based, and multimodal approaches are provided along with the authors' own experiences. Most of the endovascular modalities tested in clinical trials show recanalization rates in the range of 50% to 65%. However, no one modality is clearly superior. In practice, multimodal treatment strategy is often employed to achieve rapid recanalization of occluded cerebral vessels and minimize chances of hemorrhage. This may become the standard of care in the future.