Outcome after thrombolysis for acute isolated posterior cerebral artery occlusion

Thrombectomy vs Medical Management for Posterior Cerebral Artery Stroke: Systematic Review, Meta-Analysis, and Real-World Data

BACKGROUND AND OBJECTIVES

There is a paucity of high-level evidence for endovascular thrombectomy (EVT) in posterior cerebral artery (PCA) strokes.

METHODS

The MEDLINE, Embase, and Web of Science databases were queried for well-conducted cohort studies comparing EVT vs medical management (MM) for PCA strokes. Outcomes of interest included 90-day functional outcomes, symptomatic intracranial hemorrhage (sICH), and death. The level of evidence was determined per the Oxford Centre for Evidence-Based Medicine criteria. We also conducted a propensity score matched (PSM) analysis of the 2016-2020 National Inpatient Sample (NIS) to provide support for our findings with real-world data.

RESULTS

A total of 2,095 patients (685 EVT and 1,410 MM) were identified across 5 well-conducted cohort studies. EVT was significantly associated with higher odds of no disability at 90 days (odds ratio [OR] 1.25, 95% CI 1.04-1.50, p = 0.015) but not functional independence (OR 0.87, 95% CI 0.72-1.07, p = 0.18). EVT was also associated with higher odds of sICH (OR 2.48, 95% CI 1.55-3.97, p < 0.001) and numerically higher odds of death (OR 1.32, 95% CI 0.73-2.38; p = 0.35). PSM analysis of 95,585 PCA stroke patients in the NIS showed that EVT (n = 1,540) was associated with lower rates of good discharge outcomes (24.4% vs 30.7%, p = 0.037), higher rates of in-hospital mortality (8.8% vs 4.9%, p = 0.021), higher rates of ICH (18.2% and 11.7%, p = 0.008), and higher rates of subarachnoid hemorrhage (3.9% vs 0.6%, p < 0.001). Among patients with moderate to severe strokes (NIH Stroke Scale 5 or greater), EVT was associated with significantly higher rates of good outcomes (21.7% vs 13.8%, p = 0.023) with similar rates of mortality (7.6% vs 6.6%, p = 0.67) and ICH (17.8% vs, 13.1%, p = 0.18).

DISCUSSION

Our meta-analysis revealed that while EVT may be effective in alleviating disabling deficits due to PCA strokes, it is not associated with different odds of functional independence and may be associated with higher odds of sICH. These findings were corroborated by our large propensity score matched analysis of real-world data in the United States. Thus, the decision to pursue PCA thrombectomies should be carefully individualized for each patient. Future randomized trials are needed to further explore the efficacy and safety of EVT for the treatment of PCA strokes.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that in patients with acute PCA ischemic stroke, treatment with EVT compared with MM alone was associated with higher odds of no disabling deficit at 90 days and higher odds of sICH.

Endovascular therapy outcome in isolated posterior cerebral artery occlusion strokes: A multicenter analysis of the Swiss Stroke Registry

PURPOSE

There is little data on the safety and efficacy of endovascular treatment (EVT) in comparison with intravenous thrombolysis (IVT) in acute ischemic stroke due to isolated posterior cerebral artery occlusion (IPCAO). We aimed to investigate the functional and safety outcomes of stroke patients with acute IPCAO treated with EVT (with or without prior bridging IVT) compared to IVT alone.

METHODS

We did a multicenter retrospective analysis of data from the Swiss Stroke Registry. The primary endpoint was overall functional outcome at 3 months in patients undergoing EVT alone or as part of bridging, compared with IVT alone (shift analysis). Safety endpoints were mortality and symptomatic intracranial hemorrhage. EVT and IVT patients were matched 1:1 using propensity scores. Differences in outcomes were examined using ordinal and logistic regression models.

FINDINGS

Out of 17,968 patients, 268 met the inclusion criteria and 136 were matched by propensity scores. The overall functional outcome at 3 months was comparable between the two groups (EVT vs IVT as reference category: OR = 1.42 for higher mRS, 95% CI = 0.78-2.57, p = 0.254). The proportion of patients independent at 3 months was 63.2% in EVT and 72.1% in IVT (OR = 0.67, 95% CI = 0.32-1.37, p = 0.272). Symptomatic intracranial hemorrhages were overall rare and present only in the IVT group (IVT = 5.9% vs EVT = 0%). Mortality at 3 months was also similar between the two groups (IVT = 0% vs EVT = 1.5%).

CONCLUSION

In this multicenter nested analysis, EVT and IVT in patients with acute ischemic stroke due to IPCAO were associated with similar overall good functional outcome and safety. Randomized studies are warranted.

Endovascular Treatment of Acute Ischemic Stroke Due to Isolated Proximal Posterior Artery Occlusion

Background

Acute ischemic stroke (AIS) due to isolated proximal posterior cerebral artery (PPCA) occlusion is rare but associated with high morbidity and mortality rates. However, the optimal treatment strategy for patients with AIS caused by PPCA remains unclear. We discuss our single-center experience with endovascular treatment (EVT) in patients with PPCA.

Methods

Data from patients with AIS due to PPCA occlusion were retrospectively analyzed. We analyzed procedural details, the degree of reperfusion, functional outcomes, and complications. Functional outcomes were determined using the modified Rankin Scale (mRS) at 90 days, and good outcome was defined as mRS 0–2 at 90 days. Successful reperfusion was defined as modified treatment in cerebral ischemia (mTICI) 2b−3 after endovascular therapy. Safety variables included symptomatic hemorrhage (defined as an increase of four or more points in the National Institute of Health Stroke Scale score), vessel perforation or dissection, and new ischemic stroke in different territories.

Results

Seven patients were included in this study. The mean age of the patients was 64 ± 12.4 years. Successful reperfusion was achieved in all seven patients (100%). Good outcomes were achieved at 90 days in 2 patients (28.6%), and favorable outcomes were observed in five patients (71.4%). One patient underwent angioplasty as rescue therapy after three attempts. One patient died because of severe gastrointestinal bleeding 24 h after EVT, which was probably a complication of intravenous alteplase. One patient had an embolism in the basilar artery and achieved complete reperfusion after rescue thrombectomy. Another patient had a complication of vessel dissection in the PPCA and underwent stent implantation as rescue therapy. We observed no recurrence of ischemic stroke or any intracranial hemorrhage on non-contrast computed tomography 24 h after the procedure.

Conclusion

EVT may represent an alternative treatment strategy for patients with acute ischemic stroke caused by PPCA.

Endovascular Therapy versus No Endovascular Therapy in Patients receiving Best Medical Management for Acute Isolated Occlusion of the Posterior Cerebral Artery: Systematic Review and Meta-Analysis

BACKGROUND AND PURPOSE

Endovascular therapy (EVT) is increasingly reported for treatment of isolated posterior cerebral artery (PCA) occlusions although its clinical benefit remains uncertain. This study-level meta-analysis investigated functional outcome and safety of EVT and best medical management (BMM) compared to BMM for treatment of PCA occlusion stroke.

METHODS

We conducted a literature search in PubMed, Web of Science and Embase for articles reporting patients with isolated PCA occlusion stroke treated with EVT+BMM or BMM including intravenous thrombolysis. There were no randomized trials and all studies were retrospective. Primary outcome was a modified Rankin Scale score of 0-2 at 3 months; safety outcomes included mortality rate and incidence of symptomatic intracranial hemorrhage.

RESULTS

Twelve articles with a total of 679 patients were included in the meta-analysis consisting of 338 patients with EVT+BMM and 341 patients receiving BMM alone. Good functional outcome at 3 months was achieved in 58.0% [95% confidence interval (CI) 43.83-70.95] of patients with EVT+BMM and 48.1% [95% CI 40.35-55.92] of patients with BMM with respective mortality rates of 12.6% [7.30-20.93] and 12.3% [8.64-17.33]. Symptomatic intracranial hemorrhage occurred in 4.2% [95% CI 2.47-7.03] of patients with EVT+BMM and 3.2% [95% CI 1.75-5.92] of patients with BMM. Comparative analyses were performed of publications reporting both treatments and demonstrated no significant differences.

CONCLUSIONS

The results demonstrate that EVT represents a safe treatment for patients with isolated PCA occlusion stroke. There were no differences in clinical or safety outcomes between treatments, supporting randomization of future patients into distal vessel occlusion trials.

Acute Treatment of Isolated Posterior Cerebral Artery Occlusion: Single Center Experience

BACKGROUND AND OBJECTIVES

Randomized trials for mechanical thrombectomy (MT) excluded patients with ischemic strokes due to isolated posterior cerebral artery occlusion (IPCAO), and there is no evidence for best acute treatment strategy in these patients. We aimed to assess the effectiveness and safety of MT in acute IPCAO.

METHODS

We retrospectively analyzed consecutive patients with acute stroke due to IPCAO submitted to MT and/or intravenous thrombolysis (IVT), between 2015-2019. Effectiveness outcomes (recanalization rate, first-pass effect, NIHSS 24h improvement and 3-month Modified Ranking Scale - mRS) and safety outcomes (complications, symptomatic intracranial hemorrhage (SICH) and 3-month mortality) were described and compared between groups.

RESULTS

A total of 38 patients were included, 25 underwent MT and 13 had IVT alone. Successful and complete recanalization were achieved in 68% and 52% of MT patients, respectively. NIHSS improvement at 24h was found in 56% of MT patients versus 30.8% of patients submitted to IVT alone (OR [95% CI]=2.86 [0.69-11.82]) and excellent functional outcome at 3 months (mRS≤1) was achieved in 54.2% of MT patients versus 38.5% in the IVT group (OR [95% CI]=1.60 [0.41-6.32]). Complications occurred in 3 (12%) procedures and there were no SICH. Mortality at 3 months was 20% in the MT group and 15.4% in patients submitted to IVT alone.

CONCLUSIONS

Our results reflect a real-world scenario in a single center and seem to support the recently growing literature showing that MT is a feasible and safe treatment in IPCAO, with favorable effectiveness.

Mechanical thrombectomy versus intravenous alteplase alone in acute isolated posterior cerebral artery occlusion: a systematic review

BACKGROUND

Acute isolated posterior cerebral artery occlusions (aPCAOs) were excluded or under-represented in major randomized trials of mechanical thrombectomy (MT). The benefit of MT in comparison to intravenous tissue plasminogen activator (alteplase; IV-tPA) alone in these patients remains controversial and uncertain.

METHODS

We performed a systematic search of PubMed, MEDLINE, and EMBASE databases for articles comparing MT with or without bridging IV-tPA and IV-tPA alone for aPCAO using keywords ('posterior cerebral artery', 'thrombolysis' and 'thrombectomy') with Boolean operators. Extracted data from patients reported in the studies were pooled into groups (MT vs IV-tPA alone) for comparison. Estimated rates for favorable outcome (modified Rankin scale score 0-2), symptomatic intracranial hemorrhage (sICH), and mortality were extracted.

RESULTS

Seven articles (201 MT patients, 64 IV-tPA) were included, all retrospective. There was no statistically significant difference between pooled groups in median age, median presentation National Institutes of Health Stroke Scale (NIHSS) score, PCAO segment, and median time from symptom onset to puncture or needle. The recanalization rate was significantly higher in the MT group than the IV-tPA group (85.6% vs 53.1%, p<0.00001). Odds ratios for favorable outcome (OR 1.5, 95% CI 0.8 to 2.5), sICH (OR 1.1, 95% CI 0.2 to 5.5), and mortality (OR 1.4, 95% CI 0.5 to 3.6) did not significantly favor any modality.

CONCLUSIONS

We found no significant differences in odds of favorable outcome, sICH, and mortality in MT and IV-tPA in comparable aPCAO patients, despite superior MT recanalization rates. Equipoise remains regarding the optimal treatment modality for these patients.

Mechanical thrombectomy in isolated large vessel posterior cerebral artery occlusions

PURPOSE

Mechanical thrombectomy (MT) in posterior circulation large vessel occlusion (LVO), including posterior cerebral artery (PCA), has not been validated since all five major MT trials excluded such patients. To evaluate the feasibility and preliminary safety and efficacy of MT in isolated PCA occlusion stroke patients with new-generation MT devices.

METHODS

Endovascularly treated acute ischemic stroke (AIS) patients were identified from a prospectively collected database and their baseline characteristics were noted. Clinical outcomes were angiographic recanalization, a favorable clinical outcome at 3 months on modified Rankin Scale (mRS) and visual field (VF) deficit improvement on confrontation test, rate of intracranial hemorrhage (ICH), and mortality at 3 months.

RESULTS

A total of 355 AIS patients underwent MT from January 2018 to December 2019. Isolated PCA MT was performed in 15 consecutive patients. The mean age was 64 ± 17 years, and 9(60%) were women. Median presentation NIHSS was 9 (interquartile range 5-15). MT devices used were stent retrievers in 6 patients and combined aspiration and stent retriever in 9 patients. Complete revascularization (TICI 2c or 3) was achieved in 12/15 patients. 3-month VF normalization was seen in 7/12 of the patients. Post-procedure symptomatic ICH occurred in 1/15 of patients. mRS score of 0-2 was achieved in 9/15 of patients but one patient was dead at 3 months post procedure.

CONCLUSION

MT is feasible and can achieve successful reperfusion in isolated PCA occlusions and resulted in favorable motor and visual outcomes in this small series of ischemic stroke patients.

Should posterior cerebral artery occlusions be recanalized? Insights from the Trevo Registry

BACKGROUND AND PURPOSE

The purpose of this study was to evaluate the safety and effectiveness of mechanical thrombectomy (MT) in patients with acute ischaemic stroke related to isolated and primary posterior cerebral artery (PCA) occlusions amongst the patients enrolled in the multicentre post-market Trevo Registry.

METHOD

Amongst the 2008 patients enrolled in the Trevo Registry with acute ischaemic stroke due to large vessel occlusion treated by MT, 22 patients (1.1%) [10 females (45.5%), mean age 66.2 ± 14.3 years (range 28-91)] had a PCA occlusion [17 P1 (77.3%) and five P2 occlusions (22.7%)]. Recanalization after the first Trevo (Stryker, Fremont, CA, USA) pass and at the end of the procedure was rated using the modified Thrombolysis in Cerebral Infarction (mTICI) score. Procedure-related complications (i.e. groin puncture complication, perforation, symptomatic haemorrhage, embolus in a new territory) were also recorded. The modified Rankin Scale at 90 days was assessed.

RESULTS

Median National Institutes of Health Stroke Scale at admission was 14 (interquartile range 8-16). Stroke aetiology was cardio-embolic in 68.2% of cases. Half of the patients (11/22) received intravenous tissue plasminogen activator. 54.5% of the patients were treated under general anaesthesia. Reperfusion (i.e. mTICI 2b or 3) after first pass was obtained in 65% of cases. Final mTICI 2b-3 reperfusion was obtained in all cases. Only one (4.5%) procedure-related complication was recorded (puncture site) that resolved after surgery. At 90-day follow-up, modified Rankin Scale 0-2 was obtained in 59% of the patients and 9.1% died within the first 3 months after MT.

CONCLUSION

Mechanical thrombectomy for PCA occlusions seems to be safe (<5% procedure-related complications) and effective. Larger repository datasets are needed.

Thrombectomy and Thrombolysis of Isolated Posterior Cerebral Artery Occlusion

Background and Purpose—

We investigated efficacy and safety of acute revascularization with intravenous thrombolysis (IVT) and endovascular treatment (EVT) in ischemic stroke from isolated posterior cerebral artery occlusion, by assessing recanalization, disability, visual, cognitive outcomes, and hemorrhagic complications.

Methods—

For this retrospective single-center cohort study, we selected all consecutive patients with stroke with isolated posterior cerebral artery occlusion from the Acute Stroke Registry and Analysis of Lausanne registry between January 2003 and July 2018, and compared (1) IVT with conservative treatment (CTr) and (2) EVT to best medical therapy (BMT, ie, CTr or IVT) in terms of 3-month disability and visual field defect, and cognitive domains impaired after stroke. Unadjusted analysis, multivariable logistic regression, and propensity score matched analyses were performed.

Results—

Among 106 patients with isolated posterior cerebral artery occlusion, 21 received EVT (13 bridging), 34 IVT alone, and 51 CTr. Median age was 76 years, 47% were female and median National Institutes of Health Stroke Scale score was 7. Complete 24-hour recanalization was more frequent with IVT than CTr (51% versus 9%; OR [95% CI]=10.62 [2.13–52.92]) and with EVT compared with BMT (68% versus 34%; OR [95% CI]=4.11 [1.35–12.53]). Higher proportions of good disability, visual and cognitive outcomes were observed in IVT versus CTr, adj ORs (95% CI)=1.65 (0.60−4.52), 2.01 (0.58−7.01), 2.94 (0.35−24.4), respectively, and in EVT versus BMT, adj ORs (95% CI)=1.44 (0.51−4.10), 4.28 (1.00−18.29), 4.37 (0.72−26.53), respectively. Hemorrhagic complications and mortality did not increase with IVT or EVT.

Conclusion

s—We show increased odds of recanalization following IVT and even higher after EVT. We observed a trend for a positive effect on disability, visual, and cognitive outcomes with IVT over CTr and with EVT over BMT.

A Case of Acute Isolated Posterior Cerebral Artery Occlusion Successfully Treated with Endovascular Clot Aspiration

Posterior cerebral artery (PCA) strokes produce various symptoms. Therefore, the diagnosis is often delayed and patients arrive late for thrombolytic therapy. We report a case of acute isolated PCA occlusion that was successfully treated with endovascular clot aspiration. A 63-year-old man presented with right complete homonymous hemianopia. Diffusion-weighted image (DWI) showed a high-intensity area (HIA) in the occipital lobe, and magnetic resonance angiography (MRA) showed PCA occlusion. Emergency endovascular clot aspiration was performed immediately after the diagnosis. Blood flow in PCA completely recovered 210 min after symptom onset. DWI after surgery showed partial disappearance of HIA, and the patient recovered from the symptom of right complete homonymous hemianopia. Endovascular recanalization is useful for acute PCA occlusion. This is the first reported case of acute isolated PCA occlusion successfully treated with endovascular clot aspiration. Prompt reperfusion results in a good clinical course in patients with PCA stroke. In this case, endovascular clot aspiration resulted in prompt recanalization in a patient with acute isolated PCA occlusion.

Susceptibility Vessel Sign for Intra-arterial Thrombus in Acute Posterior Cerebral Artery Infarction

BACKGROUND

Susceptibility vessel sign (SVS) on susceptibility-weighted imaging (SWI) has a high sensitivity and specificity to detect the intra-arterial thrombus in anterior circulation stroke. However, SVS has not been evaluated in posterior circulation stroke.

METHODS

We reviewed the data from patients with acute posterior cerebral artery (PCA) infarction within 24 hours from stroke onset. To elucidate the usefulness of SVS for the detection of intraluminal thrombus in acute PCA infarction, the frequency and location of SVS were compared with those of occlusion on magnetic resonance angiography (MRA) and hyperdense PCA sign on computed tomography (CT).

RESULTS

Twenty-five patients with acute PCA infarction were enrolled in the study. The SVS was found in 92% (23 of 25). MRA showed occlusions in 64% (16 of 25). The SVS was identified in 100% (16 of 16) of patients with occlusion on MRA. Patients without occlusion on MRA also showed the SVS in 78% (7 of 9; P = .0233). The positive SVS without occlusion on MRA was mainly identified in patients with occlusion of distal branches of PCA; P3 segment in 4 and P4 segment in 3. However, the hyperdense PCA sign on CT showed in only 8% (2 of 25) of all patients; its sensitivity was significantly lower than those of the SVS on SWI (P < .001).

CONCLUSIONS

SWI is more sensitive than MRA for the detection of intraluminal thrombus, especially peripheral one, in patients with acute ischemic stroke of the PCA territory. In addition, irrespective of thrombus location, SWI is significantly superior to CT in detecting thrombus in acute PCA infarction.

Intravenous thrombolysis in ischemic stroke patients with isolated homonymous hemianopia

BACKGROUND

Patients with posterior ischemic stroke were usually excluded from thrombolytic treatment in clinical trials and clinical practice, and little is known about effectiveness of thrombolysis treatment in such patients who may end up with severe disability.

AIMS OF THE STUDY

We aimed to describe the outcome of acute ischemic stroke patients presenting with isolated homonymous hemianopia and treated with intravenous thrombolysis.

METHODS

A case report of three patients presenting with homonymous hemianopia owing to posterior circulation stroke treated with intravenous thrombolysis at the Helsinki University Central Hospital. Main outcome measures were modified Rankin Scale and neuropsychological examination at 3 months after thrombolysis. We further evaluated Goldmann visual field examination at 6 months.

RESULTS

No acute findings appeared on admission non-contrast head-computed tomography scan. All patients had a perfusion deficit on admission-computed tomography perfusion imaging. All patients scored 0 on 3-month modified Rankin Scale, and their neuropsychological evaluation was normal. Goldmann examination revealed no visual field deficit in both female patients, and a modest visual field defect was detected in the male patient.

CONCLUSIONS

Our experience encourages application of intravenous thrombolytic treatment (especially when supported with multimodality neuroimaging) in patients with homonymous hemianopia, for which rehabilitation options are limited.