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Kallmes, David F

0000-0002-8495-0040

Mayo Clinic

Department of Radiology, Mayo Clinic, 200 First St SW, Rochester, MN 55905.

Citations 39

Differences in outcome between left-sided and right-sided mechanical thrombectomy for acute ischemic stroke: A systematic review and meta-analysis

Interventional Neuroradiology | March 1, 2024 | Volume: 32 | Issue: 4 | Pages: 1594-1600

10.1177/15910199241236329 | PMID 38425287

Background Mechanical thrombectomy (MT) is a safe and effective treatment option for acute ischemic stroke due to large vessel occlusion. To investigate differences in outcomes between patients receiving left-sided and right-sided MT, we performed a systematic review and meta-analysis. Methods A systematic literature review was performed using Embase, PubMed, Scopus, and Web of Science databases. Additional literature was searched for manually. Studies reporting safety and efficacy metrics for MT were included. Data regarding the modified Rankin scale (mRS), thrombolysis in cerebral infarction (TICI), symptomatic intracranial hemorrhage (sICH), and 90-day mortality were included. A random-effects model was used to calculate pooled odds ratios (ORs), mean differences (MDs), and 95% confidence intervals (CIs). Results The literature search yielded 13 reports consisting of 19 studies ranging from 98 to 5590 patients. Patients presenting with left-sided stroke had a National Institutes of health stroke scale score 2.89 greater than patients presenting with right-sided stroke (MD = 2.89; 95% CI = 2.09–3.68; P -value < 0.001). There were no differences between left-sided and right-sided MT patients for mRS 0–2 (OR = 0.94; 95% CI = 0.85–1.04; P -value = 0.224), TICI 2b–3 (OR = 1.05; 95% CI = 0.88–1.25; P -value = 0.598), sICH (OR = 0.83; 95% CI = 0.61–1.14; P -value = 0.255), or 90-day mortality (OR = 1.06; 95% CI = 0.84–1.33; P -value = 0.610). Conclusions There does not appear to be a difference in outcomes for patients undergoing left-sided or right-sided thrombectomy.
Mechanical thrombectomy for the treatment of large vessel occlusion due to cancer-related cerebral embolism: A systematic review

Interventional Neuroradiology | February 9, 2024 | Volume: 32 | Issue: 4 | Pages: 1560-1568

10.1177/15910199241230356 | PMID 38332668

Background Cancer-related cerebral embolism due to direct tumor embolization results in a rare acute ischemic stroke with large vessel occlusion (LVO). Despite the established status of mechanical thrombectomy (MT) in LVO management, its effectiveness and safety remains inadequately explored in this specific patient group. Methods We conducted a systematic review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, using the Nested Knowledge AutoLit software, encompassing databases like Embase, PubMed, Scopus, and Web of Science, from their inception up to 9 May 2023. Results In the review of 35 studies encompassing 37 cases, mean patient age was 52 years, and 30% were female. Cardiac myxoma (29.7%), cardiac papillary fibroelastoma (16.2%), and squamous cell carcinoma of the lung (8.1%) were the most frequent underlying cancers. The left middle cerebral artery was the most commonly affected occlusion site (24.3%). Of the patients, 67.5% underwent MT alone, while 32.5% received MT combined with intravenous thrombolysis. Successful reperfusion (thrombolysis in cerebral infarction (TICI) 2b–3) was achieved in 89.1% of cases, with 59.4% reaching TICI 3. Functional independence was observed in 29.7% of patients. Conclusion While limitations exist, this comprehensive study highlights the potential benefits of MT in a patient group historically excluded from major trials, warranting further investigation.
Safety and efficacy of the Woven Endo-Bridge-17 device for intracranial aneurysm treatment: A systematic review and meta-analysis

Interventional Neuroradiology | January 18, 2024 | Volume: 32 | Issue: 3 | Pages: 964-970

10.1177/15910199231226294 | PMID 38234203

Background The Woven Endo-Bridge (WEB) device revolutionized the treatment of wide-necked bifurcation aneurysms by intrasaccular flow diversion. The latest advancement is the WEB-17 system, offering greater flexibility with fewer wires, enabling treatment of smaller distal aneurysms using smaller microcatheters than the WEB-21 system. Methods We conducted a systematic review following preferred reporting items for systematic reviews and meta-analyses guidelines, analyzing data from seven retrospective cohort studies involving 483 aneurysms treated with the WEB-17 device. Statistical analysis computed pooled prevalence rates and 95% confidence intervals using appropriate models for each outcome and R software version 4.3.1 (R Foundation for Statistical Computing, Vienna, Austria). Results Technical success was achieved in 475 out of 483 aneurysms treated with the WEB-17 device, with a success rate of 98.34% (95% confidence interval (CI) = 96.72–99.17). Among the successful cases, 4.97% (95% CI = 1.60–14.39) required adjunctive devices. Adequate occlusion, defined as complete occlusion or neck remnants, was observed in 94.41% (95% CI = 88.17–97.46) of cases. Periprocedural complications were infrequent, with thromboembolic complications occurring in 4.93% (95% CI = 3.29–7.30) of cases, hemorrhagic complications in 1.28% (95% CI = 0.58–2.83), and postprocedural neurologic complications in 0.99% (95% CI = 0.31–3.14). Procedure-related morbidity was observed in 1.71% (95% CI = 0.86–3.39) of cases, and there was one procedure-related mortality reported at 0.21% (95% CI = .03–1.50). Mortality unrelated to the procedure occurred in 1% (95% CI = 0.23–4.15). Conclusion Our findings suggest that the WEB-17 device is associated with a high rate of technical success, favorable angiographic outcomes, and a low rate of periprocedural complications. Further research, including prospective trials, is needed to confirm these findings and establish its safety and efficacy definitively.
Disability-free outcomes after mechanical thrombectomy: A systematic review and meta-analysis of the randomized controlled trials

Interventional Neuroradiology | January 5, 2024 | Volume: 32 | Issue: 3 | Pages: 898-907

10.1177/15910199231224826 | PMID 38179678

Background The modified Rankin Scale (mRS) score of ≤2 (functional independence) has been the most common primary endpoint of modern mechanical thrombectomy (MT) trials. However, unlike mRS 0-1, mRS score of 2 indicates disability. An important proportion of the mRS 2 patients are home dependent and report a significant decrease in their quality of life. Purpose To investigate excellent outcome (mRS 0-1) rates after MT. Methods We systematically searched Ovid MEDLINE, Ovid EMBASE, Cochrane Central Register of Controlled Trials, Scopus, and Web of Science databases. Randomized controlled trials (RCTs) investigating the role of modern MT in acute ischemic stroke were screened. Posterior circulation and large-core infarct trials were excluded from the study. The data regarding excellent outcomes (mRS: 0-1), functional independence (mRS: 0-2), and reperfusion were collected. Results Twenty-two RCTs comprising 5692 patients were included in the meta-analysis. The overall mRS 0-1 rate was 31.24% (95% CI = 26.95–36.2). The rate of successful reperfusion was 81.8% (95% CI = 77.93–85.86). MT achieved significantly higher rates of mRS 0-1 compared to standard care alone (OR = 2.04; 95% CI = 1.64–2.55; P-value < 0.001), with no heterogeneity detected among studies (I 2 = 0%; P-value = 0.52). The direct MT and MT plus intravenous thrombolytic treatment groups’ excellent outcome rates were comparable (OR = 0.98; 95% CI = 0.82–1.18; P-value = 0.863). Also, aspiration and stent retriever thrombectomy techniques provided similar excellent outcome rates (OR = 0.76; 95% CI = 0.55–1.05; P-value = 0.141). Conclusions Our results prove the additional benefit of MT over standard care, using a stricter definition for favorable functional outcome. Nearly one-third of patients presenting with large artery occlusion and treated with MT had no disability at 90 days. While this is remarkable, our results also indicate that reperfusion alone is often not enough to prevent disability and underline the need for better neuroprotection strategies.
Comparative analysis of syringes versus pump devices in benchtop aspiration thrombectomy models: A systematic review and meta-analysis

Interventional Neuroradiology | December 27, 2023 | Volume: 32 | Issue: 3 | Pages: 891-897

10.1177/15910199231222305 | PMID 38151033

Background Although direct contact aspiration has emerged as one of the leading techniques for mechanical thrombectomy (MT), there is still ongoing debate about the aspiration/suction pump devices that can optimize recanalization rates. To address this gap, we conducted a meta-analysis comparing the aspiration efficacy of 60 ml syringe and pump devices in benchtop MT models. Methods Systematic literature review was conducted using Medline, Embase, Web of Science, and Scopus in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Outcomes of interest included flow rate and vacuum pressure delivered by a 60 ml syringe and several aspiration pumps. We used a random effects model to calculate the mean difference (MD) with 95% confidence intervals (CIs) and a statistically significant difference was considered as a two-sided p -value of less than 0.05. Results We included six benchtop studies comparing 60 ml syringes and vacuum pumps. Our meta-analysis showed that there were no significant differences in vacuum pressure (MD:0.71inHg, 95% CI: [−0.81;2.23], p = 0.359) and flow rate (MD:0.27 mL/s, 95% CI: [−3,07; 3.61], p = 0.873) between 60 ml syringes and vacuum pumps groups. Conclusions Our study demonstrated comparable performance in terms of vacuum pressure and flow rates between a 60 ml syringe and a heterogeneous combination of commercially available aspiration pumps.
Distal versus conventional transradial access for diagnostic cerebral angiography and neurointerventional procedures: A systematic review and meta-analysis

Interventional Neuroradiology | November 8, 2023 | Volume: 32 | Issue: 3 | Pages: 881-890

10.1177/15910199231210411 | PMID 37936400

Background Distal transradial artery access (dTRA) has received increasing consideration for performing diagnostic cerebral angiography and neurointerventional procedures. In this meta-analysis, we aim to evaluate the safety and efficacy of dTRA compared to conventional transradial access (cTRA) for cerebral angiography and neurointerventions. Method A systematic review and meta-analysis were conducted on studies investigating outcomes of dTRA and cTRA in neurointerventions. The primary outcome was technical success rates. Secondary outcomes included access site complication rates, crossover rates to alternative vessels, fluoroscopy time, and contrast volume. The random effects model was used to calculate the mean difference (MD) and odds ratios (OR) with 95% confidence intervals (Cl). Results Eight retrospective observational studies with a total of 1477 patients who underwent 1175 diagnostic cerebral angiography and 516 neurointerventional procedures using 546 dTRA and 1164 cTRA approaches were included in our meta-analysis. The technical success rate was similar between dTRA and cTRA groups (95.8% vs 91.4%; OR:1.65; 95% Cl: 0.52 to 5.22; P = 0.40). Similarly, no difference was seen in dTRA and cTRA regarding access site complications (2% vs 1.4%; OR: 1.31; 95% CI: 0.47 to 3.61; P = 0.61) and access site crossover (2.1% vs 5.3%; OR: 0.55; 95% Cl: 0.28 to 1.05; P = 0.07). After resolving heterogeneity among included studies, dTRA was associated with a shorter fluoroscopy time (MD: −0.91 min; 95% CI: −1.74 to −0.09; P = 0.03) and lower contrast volume (MD: −8.32 mL; 95% CI = −14.7 to −1.94; P = 0.011). Conclusion Our findings suggest that the dTRA approach is a safe and effective alternative to the cTRA approach in patients undergoing cerebral angiography and neurointerventions.
Impact of smoking on outcomes following endovascular therapy for acute ischemic stroke: A systematic review and meta-analysis

Interventional Neuroradiology | October 5, 2023 | Volume: 32 | Issue: 3 | Pages: 849-854

10.1177/15910199231206100 | PMID 37796821

Background Smoking represents a leading risk factor for acute ischemic stroke (AIS). Previous literature has described a “smoking paradox”, wherein smokers experience better outcomes following intravenous thrombolysis for AIS. It is unclear whether such a phenomenon exists in smokers undergoing endovascular therapy (EVT) for AIS. To assess outcomes in smokers following EVT for AIS, we conducted a systematic review and meta-analysis. Methods Following the PRISMA guidelines, a systematic literature review of the English language literature was conducted using PubMed, Embase Web of Science, and Scopus. Outcomes of interest included 90-day modified Rankin Scale (mRS) 0–2, thrombolysis in cerebral infarction (TICI) score 2b-3, symptomatic intracranial hemorrhage (sICH), and mortality. We calculated mean difference (MD), pooled odds ratios (ORs) and their corresponding 95% confidence intervals (CI). Results Eight studies with 2633 patients comprised our analysis. On average, smokers were 10.14 years (MD = 10.14, [95% CI = −14.49 to −5.79], P-value < 0.001) younger than non-smokers. Smokers achieved mRS 0–2 (OR = 1.82, [95% CI, 1.34–2.48], P-value < 0.001) and TICI 2b-3 (OR = 1.61, [95% CI, 1.19–2.19], P-value = 0.002) at a higher rate than non-smokers. sICH rates were comparable between smokers and non-smokers (OR = 1.07, [95% CI, 0.62–1.85], P-value = 0.81). Smokers had a lower rate of 90-day mortality than non-smokers (OR = 0.54, [95% CI, 0.41–0.71], P-value < 0.001). Conclusions In this meta-analysis of eight studies, we found that smokers with AIS undergoing EVT experienced better 90-day outcomes and higher rates of TICI 2b-3. This may be due to baseline differences between smokers and non-smokers, but future studies should explore alternative reasons that could explain this relationship between smoking and AIS treated with EVT.
Middle meningeal artery embolization combined with surgical evacuation for chronic subdural hematoma: A single-center experience of 75 cases

Interventional Neuroradiology | August 28, 2023 | Volume: 32 | Issue: 2 | Pages: 162-169

10.1177/15910199231196453 | PMID 37635326

Background Chronic subdural hematoma (cSDH) is a challenging and common neurosurgical condition. Our goal is to demonstrate that middle meningeal artery (MMA) embolization combined with surgical evacuation can be a promising adjuvant option for treatment of cSDHs and prevent recurrence in symptomatic patients who require surgical treatment. Method We retrospectively collected data from patients who underwent MMA embolization using polyvinyl alcohol particles and surgical evacuation with burr hole or craniotomy in a single center for the treatment of new and recurrent cSDHs. The primary outcome was recurrence of cSDH requiring surgical rescue during follow up, and secondary outcomes were defined as >50% decrease in the maximum width of cSDHs on the longest follow-up computed tomography (CT) scan, complications following procedure, and improvement in modified Rankin scale (mRS) score. Results A total of 51 patients successfully underwent 72 MMA embolization procedures (96% of the total 75 cases in the cohort) combined with surgical evacuation. Seventy cases (93.3%) achieved at least 50% reduction in the size of the cSDHs on the last CT imaging. A surgical evacuation was required in five cases (6.7%) due to cSDH recurrence during the follow-up period. There were three complications (6.0%) related to embolization procedure. Forty patients (78.4%) showed improvement in mRS score. There was one mortality (2%) regardless of the embolization and evacuation. Conclusions Our study demonstrates the safety and efficacy of adjunct MMA embolization in significantly reducing size and recurrence of cSDHs.
Endovascular treatment outcomes of vertebrobasilar junction aneurysms: Systematic review and meta-analysis

Interventional Neuroradiology | August 14, 2023 | Volume: 32 | Issue: 3 | Pages: 804-811

10.1177/15910199231194687 | PMID 37574971

Background Vertebrobasilar junction (VBJ) aneurysms represent a relatively rare and often anatomically complex subgroup of saccular aneurysms. This systematic review and meta-analysis aimed to assess the safety and efficacy of endovascular treatment (EVT) of VBJ aneurysms. Methods PubMed, Web of Science, Ovid Medline, Ovid Embase, and Scopus were searched from inception to 20 December 2022. We included primary studies assessing the long-term clinical and angiographic outcomes for VBJ aneurysms treated with endovascular techniques. We excluded surgically managed studies. All data were analyzed using R software version 4.2.1. We calculated pooled prevalence rates and their corresponding 95% confidence intervals (CI). Results In this meta-analysis, a total of 76 VBJ aneurysms from seven studies were included for quantitative analysis. The results showed that the rate of adequate occlusion (complete + near complete occlusion) was 94.1% (95% CI = 76.71–98.71), and the rate of complete occlusion was 77.7% (95% CI = 63.07–87.65). A modified Rankin Scale (mRS) score of 0–2 was achieved in 93.9% of patients (95% CI = 67.65–99.14). The mortality rate was found to be 5.9% (95% CI = 0.97–28.55), and the retreatment rate was 4.6% (95% CI = 1.50–13.36). The overall ischemic complication rate was 4.7% (95% CI = 0.73–25.4), while the overall hemorrhagic complication rate was 4.6% (95% CI = 1.5–13.36). Conclusions The treatment of VBJ aneurysms with EVT is effective in achieving curative treatment and is associated with good clinical outcomes and low mortality rates. These findings provide important insights into the clinical and angiographic outcomes and the complication rates of EVT for VBJ aneurysms.
2b Or 2c-3? A meta-analysis of first pass thrombolysis in cerebral infarction 2b vs multiple pass thrombolysis in cerebral infarction 2c-3 following mechanical thrombectomy for stroke

Interventional Neuroradiology | August 8, 2023 | Volume: 32 | Issue: 1 | Pages: 33-38

10.1177/15910199231193925 | PMID 37551104

Background Procedural success following mechanical thrombectomy for acute ischemic stroke is assessed using the thrombolysis in cerebral infarction scale. We conducted a systematic review and meta-analysis to determine whether outcomes differed between first pass thrombolysis in cerebral infarction 2b and multiple pass thrombolysis in cerebral infarction 2c-3. Methods We conducted a systematic review of the literature using PubMed, Embase, Scopus, and Web of Science. We included original studies in which outcomes were stratified based on first pass thrombolysis in cerebral infarction 2b and multiple pass thrombolysis in cerebral infarction 2c-3. The primary outcome of interest was the rate of modified Rankin Scale 0-2. Secondary outcomes of interest were rates of modified Rankin Scale 0-1, symptomatic intracranial hemorrhage, and mortality. We calculated odds ratios and corresponding 95% confidence intervals. Results Four studies with 1554 patients were included in the quantitative analysis. Rate of modified Rankin Scale 0–2 (odds ratio = 0.91, 95% confidence interval = 0.70–1.18; P -value = 0.49), modified Rankin Scale 0–1 (odds ratio = 1.21, 95% confidence interval = 0.86–1.71; P -value = 0.27), symptomatic intracranial hemorrhage (odds ratio = 1.36, 95% confidence interval = 0.47–3.98; P -value = 0.57), and mortality (odds ratio = 0.91, 95% confidence interval = 0.67–1.25; P -value = 0.56) did not differ between first pass thrombolysis in cerebral infarction 2b and multiple pass thrombolysis in cerebral infarction 2c-3. There was no heterogeneity among included studies for modified Rankin Scale 0–2, modified Rankin Scale 0–1, or mortality; however, there was moderate heterogeneity among studies for symptomatic intracranial hemorrhage ( I 2 = 53%, P -value = 0.12). Conclusions Clinical and safety outcomes did not differ between first pass thrombolysis in cerebral infarction 2b and multiple pass thrombolysis in cerebral infarction 2c-3. Future prospective studies and clinical trials should determine whether first pass thrombolysis in cerebral infarction 2b is a viable endpoint to thrombolysis in cerebral infarction 2c-3.