Safety and effectiveness of mechanical thrombectomy for acute ischemic stroke using single plane angiography

Mechanical Thrombectomy for Middle Cerebral Artery Medium Vessel Occlusions Using Single Plane Angiography

BACKGROUND AND PURPOSE

Endovascular thrombectomy is now the standard of care for large vessel occlusion acute ischemic stroke. However, acute stroke due to medium-vessel occlusions often result in unfavorable outcomes, and guidelines for thrombectomy are lacking. Moreover, nearly all clinical data and thrombectomy trials are based on biplane angiography systems. This study aims to compare the safety and efficacy of stroke thrombectomy procedures performed on single-plane versus biplane angiography systems in patients presenting with medium-vessel occlusions of the middle cerebral artery.

MATERIALS AND METHODS

This retrospective study included consecutive patients with acute ischemic stroke due to primary middle cerebral artery medium-vessel occlusions treated with thrombectomy between 7/1/2020 and 8/1/2022 at a single high-volume practice. Patients were dichotomized into those treated on single plane and biplane systems. Demographic, procedural, clinical and follow-up characteristics were compared.

RESULTS

Among the 149 patients included, 44 underwent thrombectomy on single-plane systems, and 93 on biplane systems. No significant differences were detected in rates of good functional outcomes (mRS < 2; SP 54% vs BP 42%, p = 0.19), successful recanalization (TICI ≥ 2B; SP 91% vs BP 86%, p = 0.77), intra-procedural vascular injury (SP 0% vs BP 3%; p = 0.56), or time from groin puncture to reperfusion (SP 25 min vs BP 27 min; p = 0.97). No significant differences were detected in peri-procedural complications, or symptomatic intracerebral hemorrhage.

CONCLUSION

Thrombectomy for middle cerebral artery medium-vessel occlusions performed on single-plane angiography systems is as safe and efficacious as biplane procedures. Our results may have implications for increasing access to care, especially in regions with limited resources.

Comparative analysis of single plane and biplane angiography systems for mechanical thrombectomy for acute ischemic stroke: a systematic review and meta-analysis

BACKGROUND

The choice of angiography system could influence the outcomes of mechanical thrombectomy (MT) in the treatment of acute ischemic stroke (AIS), but its impact is not yet well understood. This study aims to compare the clinical and technical outcomes of MT performed with single plane versus biplane angiography systems.

METHOD

We conducted a systematic review and meta-analysis, following PRISMA guidelines, by searching PubMed, Embase, Web of Science, and Scopus to include studies on patients with AIS who underwent MT with either single plane or biplane angiography up to May 4, 2024. The primary outcome was a favorable outcome defined as a modified Rankin Scale (mRS) score of 0-2 at 90 days after the procedure. Data were analyzed using a random-effects model and heterogeneity was assessed using the I2 test and Q statistics.

RESULTS

Five studies with a total of 1562 patients were analyzed. Of these, 68.4% were treated with biplane systems and 31.6% with single plane systems. Single plane angiography was associated with a significantly higher rate of favorable outcomes (OR 1.43; 95% CI 1.13 to 1.80; P<0.01). There were no significant differences in successful recanalization, periprocedural complications, procedure time, total fluoroscopy time, or contrast volume between the two systems.

CONCLUSION

While single plane angiography systems may offer slightly better outcomes in MT for AIS, both systems appear equally effective in most clinical and technical perspectives, suggesting that system selection may be more dependent on availability and procedural requirements rather than inherent superiority. Our findings may encourage clinicians to use single-plane angiography in settings where the biplane angiography suite availability is limited, but it should be noted that this observation may have been influenced by selection bias, particularly since the larger studies included in our meta-analysis did not observe this effect in adjusted analyses for potential confounder factors.

High relative cerebral blood volume is associated with good long term clinical outcomes in acute ischemic stroke: a retrospective cohort study

BACKGROUND

Endovascular therapy for acute ischemic stroke has been shown to be highly effective in selected patients. However, the ideal criteria for patient selection are still debated. It is well known that collateral flow is an important factor, but the assessment is often subjective and time-consuming. Relative cerebral blood volume (rCBV) is a putative indicator of collateral capacity and can be quickly and easily determined by automated quantitative analysis. We investigated the relationship between rCBV of the affected region and clinical outcome in patients with acute ischemic stroke after endovascular therapy.

METHODS

We conducted a retrospective study on consecutive patients between January 2017 and May 2019. Patients with acute ischemic stroke of the anterior circulation who underwent imaging including computed tomography perfusion and were treated with mechanical thrombectomy (MT) were eligible for inclusion. rCBV was calculated automatically with RAPID software by dividing the average cerebral blood volume (CBV) of the affected region (time-to-maximum (Tmax) > 6 s) by the CBV of the unaffected contralateral side. The primary outcome was determined by the modified Rankin Scale (mRS) after 90 days. Good clinical outcome was defined as mRS ≤ 2. We compared means, performed mono- and multivariate logistical regression and calculated a receiver operating characteristic (ROC)-analysis to determine the ideal cutoff value to predict clinical outcomes.

RESULTS

155 patients were enrolled in this study. 66 patients (42.58%) had good clinical outcomes. Higher rCBV was associated with good clinical outcome (p < 0.001), even after adjustment for the patients' status according to mRS and National Institute of Health Stroke Scale (NIHSS) age and Alberta stroke program early computed tomography score (ASPECTS) at baseline (p = 0.006). ROC-analysis revealed 0.650 (confidence interval: 0.616-0.778) as the optimal cutoff value.

CONCLUSION

Higher rCBV at baseline is associated with good clinical long-term outcomes in patients with acute ischemic stroke treated by MT. In this study we provide the biggest collective so far that gives evidence that rCBV can be a valuable tool to identify patients who might benefit from MT and are able give a threshold to help to offer patients MT in borderline cases.

Modeling optimal patient transport in a stroke network capable of remote telerobotic endovascular therapy

BACKGROUND

Telerobotic endovascular therapy (EVT) has the potential to decrease time to treatment and expand existing networks of care to more rural populations. It is currently unclear how its implementation would impact existing stroke networks.

METHODS

Conditional probability models were generated to predict the probability of excellent outcome for patients with suspected large vessel occlusion (LVO). A baseline stroke network was created for California using existing intravenous thrombolysis (IVT) centers and comprehensive stroke centers (CSCs) capable of IVT and EVT. Optimal transport decisions and catchment areas were generated for the baseline model and three hypothetical scenarios through conversion of IVT centers at various distances from a CSC into centers capable of telerobotic EVT [i.e., hospitals ≥15 and <50 miles from a CSC were converted (Scenario 1), ≥50 and <100 miles (Scenario 2), and ≥100 miles (Scenario 3)]. Procedural times and success rates were varied systematically.

RESULTS

Telerobotic EVT centers decreased median travel time for LVO patients in all three scenarios. The estimated number of robotically treated LVOs per year in Scenarios 1, 2, and 3 were 2,172, 740, and 212, respectively. Scenario 1 (15-50 miles) was the most sensitive to robotic time delay and success rate, but all three scenarios were more sensitive to decreases in procedural success rate compared to time delay.

CONCLUSIONS

Telerobotic EVT has the potential to improve care for stroke patients outside of major urban centers. Compared to procedural time delays in robotic EVT, a decrease in procedural success rate would not be well tolerated.

World Federation for Interventional Stroke Treatment (WIST) Multispecialty Training Guidelines for Endovascular Stroke Intervention

INTRODUCTION

Today, endovascular treatment (EVT) is the therapy of choice for strokes due to acute large vessel occlusion, irrespective of prior thrombolysis. This necessitates fast, coordinated multi-specialty collaboration. Currently, in most countries, the number of physicians and centres with expertise in EVT is limited. Thus, only a small proportion of eligible patients receive this potentially life-saving therapy, often after significant delays. Hence, there is an unmet need to train a sufficient number of physicians and centres in acute stroke intervention in order to allow widespread and timely access to EVT.

AIM

To provide multi-specialty training guidelines for competency, accreditation and certification of centres and physicians in EVT for acute large vessel occlusion strokes.

MATERIAL AND METHODS

The World Federation for Interventional Stroke Treatment (WIST) consists of experts in the field of endovascular stroke treatment. This interdisciplinary working group developed competency - rather than time-based - guidelines for operator training, taking into consideration trainees' previous skillsets and experience. Existing training concepts from mostly single specialty organizations were analysed and incorporated.

RESULTS

The WIST establishes an individualized approach to acquiring clinical knowledge and procedural skills to meet the competency requirements for certification of interventionalists of various disciplines and stroke centres in EVT. WIST guidelines encourage acquisition of skills using innovative training methods such as structured supervised high-fidelity simulation and procedural performance on human perfused cadaveric models.

CONCLUSIONS

WIST multispecialty guidelines outline competency and quality standards for physicians and centres to perform safe and effective EVT. The role of quality control and quality assurance is highlighted.

SUMMARY

The World Federation for Interventional Stroke Treatment (WIST) establishes an individualized approach to acquiring clinical knowledge and procedural skills to meet the competency requirements for certification of interventionalists of various disciplines and stroke centres in endovascular treatment (EVT). WIST guidelines encourage acquisition of skills using innovative training methods such as structured supervised high-fidelity simulation and procedural performance on human perfused cadaveric models. WIST multispecialty guidelines outline competency and quality standards for physicians and centers to perform safe and effective EVT. The role of quality control and quality assurance is highlighted.

SIMULTANEOUS PUBLICATION

The WIST 2023 Guidelines are published simultaneously in Europe (Adv Interv Cardiol 2023).