Access to Mechanical Thrombectomy for Ischemic Stroke in the United States.

Background and Purpose: Mechanical thrombectomy helps prevent disability in patients with acute ischemic stroke involving occlusion of a large cerebral vessel. Thrombectomy requires procedural expertise and not all hospitals have the staff to perform this intervention. Few population-wide data exist regarding access to mechanical thrombectomy. Methods: We examined access to thrombectomy for ischemic stroke using discharge data from calendar years 2016 to 2018 from all nonfederal emergency departments and acute care hospitals across 11 US states encompassing 80 million residents. Facilities were classified as hubs if they performed mechanical thrombectomy, gateways if they transferred patients who ultimately underwent mechanical thrombectomy, and gaps otherwise. We used standard descriptive statistics and unadjusted logistic regression models in our primary analyses. Results: Among 205 681 patients with ischemic stroke, 100 139 (48.7% [95% CI, 48.5%­48.9%]) initially received care at a thrombectomy hub, 72 534 (35.3% [95% CI, 35.1%­35.5%]) at a thrombectomy gateway, and 33 008 (16.0% [95% CI, 15.9%­16.2%]) at a thrombectomy gap. Patients who initially received care at thrombectomy gateways were substantially less likely to ultimately undergo thrombectomy than patients who initially received care at thrombectomy hubs (odds ratio, 0.27 [95% CI, 0.25­0.28]). Rural patients had particularly limited access: 27.7% (95% CI, 26.9%­28.6%) of such patients initially received care at hubs versus 69.5% (95% CI, 69.1%­69.9%) of urban patients. For 93.8% (95% CI, 93.6%­94.0%) of patients with stroke at gateways, their initial facility was capable of delivering intravenous thrombolysis, compared with 76.3% (95% CI, 75.8%­76.7%) of patients at gaps. Our findings were unchanged in models adjusted for demographics and comorbidities and persisted across multiple sensitivity analyses, including analyses adjusting for estimated stroke severity. Conclusions: We found that a substantial proportion of patients with ischemic stroke across the United States lacked access to thrombectomy even after accounting for interhospital transfers. US systems of stroke care require further development to optimize thrombectomy access.

Nationwide Analysis of Endovascular Thrombectomy Provider Specialization for Acute Stroke.

BACKGROUND AND PURPOSE: Determine the extent of cerebrovascular expertise among the specialties of proceduralists providing endovascular thrombectomy (ET) for emergent large vessel occlusion stroke in the modern era of acute stroke among Medicare beneficiaries Methods: Retrospective cohort study using validated International Classification of Diseases, Tenth Revision, Clinical Modification codes to identify admissions with acute ischemic stroke and treatment with ET. We identified proceduralist specialty by linking the National Provider Identifier provided by Medicare to the specialty listed in the National Provider Identifier database, grouping into radiology, neurology, neurosurgery, other surgical, and internal medicine. We calculated the number of proceduralists and hospitals who performed ET, ET team specialty composition by hospital, and number of proceduralists who performed ET at multiple hospitals. RESULTS: Forty-two percent (n=5612) of ET were performed by radiology-background proceduralists, with unclear knowledge of how many were cerebrovascular specialists. Neurosurgery- and neurology-background interventionalists performed fewer but substantial numbers of cases, accounting for 24% (n=3217) and 23% (n=3124) of total cases, respectively. ET teams included a neurology- or neurosurgery-background proceduralist at 65% (n=407) of hospitals that performed ET and included both in 26% (n=160) of teams. CONCLUSIONS: Almost two-thirds of ET teams nationwide include a neurology- or neurosurgery-background proceduralist and higher volume centers in urban areas were more likely to have neurology- or neurosurgery-background proceduralists with cerebrovascular expertise on their team. It is unclear how many radiology-background interventionalists are cerebrovascular specialists versus generalists. Significant work remains to be done to understand the impact of proceduralist specialty, training, and cerebrovascular expertise on ET outcomes.

Management of cardiovascular emergencies during the COVID-19 pandemic.

BACKGROUND: It has been reported that patients attending the emergency department with other pathologies may not have received optimal medical care due to the lockdown measures in the early phase of the COVID-19 pandemic. METHODS: This was a retrospective study of patients presenting with cardiovascular emergencies to four tertiary regional emergency departments in western India during the government implementation of complete lockdown. RESULTS: 25.0% of patients during the lockdown period and 17.4% of patients during the pre-lockdown period presented outside the window period (presentation after 12 hours of symptom onset) compared with only 6% during the pre-COVID period. In the pre-COVID period, 46.9% of patients with ST elevation myocardial infarction underwent emergent catheterisation, while in the pre-lockdown and lockdown periods, these values were 26.1% and 18.8%, respectively. The proportion of patients treated with intravenous thrombolytic therapy increased from 18.4% in the pre-COVID period to 32.3% in the post-lockdown period. Inhospital mortality for acute coronary syndrome (ACS) increased from 2.69% in the pre-COVID period to 7.27% in the post-lockdown period. There was also a significant decline in emergency admissions for non-ACS conditions, such as acute decompensated heart failure and high degree or complete atrioventricular block. CONCLUSION: The COVID-19 pandemic has led to delays in patients seeking care for cardiac problems and also affected the use of optimum therapy in our institutions.

Cost-effectiveness of Mechanical Thrombectomy More Than 6 Hours After Symptom Onset Among Patients With Acute Ischemic Stroke.

Importance: Two 2018 randomized controlled trials (DAWN and DEFUSE 3) demonstrated the clinical benefit of mechanical thrombectomy (MT) more than 6 hours after onset in acute ischemic stroke (AIS). Health-economic evidence is needed to determine whether the short-term health benefits of late MT translate to a cost-effective option during a lifetime in the United States. Objective: To compare the cost-effectiveness of 2 strategies (MT added to standard medical care [SMC] vs SMC alone) for various subgroups of patients with AIS receiving care more than 6 hours after symptom onset. Design, Setting, and Participants: This economic evaluation study used the results of the DAWN and DEFUSE 3 trials to populate a cost-effectiveness model from a US health care perspective combining a decision tree and Markov trace. The DAWN and DEFUSE 3 trials enrolled 206 international patients from 2014 to 2017 and 182 US patients from 2016 to 2017, respectively. Patients were followed until 3 months after stroke. The clinical outcome at 3 months was available for 29 subgroups of patients with AIS and anterior circulation large vessel occlusions. Data analysis was conducted from July 2018 to October 2019. Exposures: MT with SMC in the extended treatment window vs SMC alone. Main Outcomes and Measures: Expected costs and quality-adjusted life-years (QALYs) during lifetime were estimated. Deterministic results (incremental costs and effectiveness, incremental cost-effectiveness ratios, and net monetary benefit) were presented, and probabilistic analyses were performed for the total populations and 27 patient subgroups. Results: In the DAWN study, the MT group had a mean (SD) age of 69.4 (14.1) years and 42 of 107 (39.3%) were men, and the control group had a mean (SD) age of 70.7 (13.2) years and 51 of 99 (51.5%) were men. In the DEFUSE 3 study, the MT group had a median (interquartile range) age of 70 (59-79) years, and 46 of 92 (50.0%) were men, and the control group had a median (interquartile range) age of 71 (59-80) years, and 44 of 90 (48.9%) were men. For the total trial population, incremental cost-effectiveness ratios were $662/QALY and $13 877/QALY based on the DAWN and DEFUSE 3 trials, respectively. MT with SMC beyond 6 hours had a probability greater than 99.9% of being cost-effective vs SMC alone at a willingness-to-pay threshold of $100 000/QALY. Subgroup analyses showed a wide range of probabilities for MT with SMC to be cost-effective at a willingness-to-pay threshold of $50 000/QALY, with the greatest uncertainty observed for patients with a National Institute of Health Stroke Scale score of at least 16 and for those aged 80 years or older. Conclusions and Relevance: The results of this study suggest that late MT added to SMC is cost-effective in all subgroups evaluated in the DAWN and DEFUSE 3 trials, with most results being robust in probabilistic sensitivity analyses. Future MT evidence-gathering could focus on older patients and those with National Institute of Health Stroke Scale scores of 16 and greater.

Acute Stroke Care Is at Risk in the Era of COVID-19: Experience at a Comprehensive Stroke Center in Barcelona.

BACKGROUND AND PURPOSE: The purpose of the study is to analyze how the coronavirus disease 2019 (COVID-19) pandemic affected acute stroke care in a Comprehensive Stroke Center. METHODS: On February 28, 2020, contingency plans were implemented at Hospital Clinic of Barcelona to contain the COVID-19 pandemic. Among them, the decision to refrain from reallocating the Stroke Team and Stroke Unit to the care of patients with COVID-19. From March 1 to March 31, 2020, we measured the number of emergency calls to the Emergency Medical System in Catalonia (7.5 million inhabitants), and the Stroke Codes dispatched to Hospital Clinic of Barcelona. We recorded all stroke admissions, and the adequacy of acute care measures, including the number of thrombectomies, workflow metrics, angiographic results, and clinical outcomes. Data were compared with March 2019 using parametric or nonparametric methods as appropriate. RESULTS: At Hospital Clinic of Barcelona, 1232 patients with COVID-19 were admitted in March 2020, demanding 60% of the hospital bed capacity. Relative to March 2019, the Emergency Medical System had a 330% mean increment in the number of calls (158 005 versus 679 569), but fewer Stroke Code activations (517 versus 426). Stroke admissions (108 versus 83) and the number of thrombectomies (21 versus 16) declined at Hospital Clinic of Barcelona, particularly after lockdown of the population. Younger age was found in stroke admissions during the pandemic (median [interquartile range] 69 [64-73] versus 75 [73-80] years, P=0.009). In-hospital, there were no differences in workflow metrics, angiographic results, complications, or outcomes at discharge. CONCLUSIONS: The COVID-19 pandemic reduced by a quarter the stroke admissions and thrombectomies performed at a Comprehensive Stroke Center but did not affect the quality of care metrics. During the lockdown, there was an overload of emergency calls but fewer Stroke Code activations, particularly in elderly patients. Hospital contingency plans, patient transport systems, and population-targeted alerts must act concertedly to better protect the chain of stroke care in times of pandemic.

Geographic Access to Stroke Care Services in Rural Communities in Ontario, Canada.

BACKGROUND: Optimal stroke care requires access to resources such as neuroimaging, acute revascularization, rehabilitation, and stroke prevention services, which may not be available in rural areas. We aimed to determine geographic access to stroke care for residents of rural communities in the province of Ontario, Canada. METHODS: We used the Ontario Road Network File database linked with the 2016 Ontario Acute Stroke Care Resource Inventory to estimate the proportion of people in rural communities, defined as those with a population size <10,000, who were within 30, 60, and 240 minutes of travel time by car from stroke care services, including brain imaging, thrombolysis treatment centers, stroke units, stroke prevention clinics, inpatient rehabilitation facilities, and endovascular treatment centers. RESULTS: Of the 1,496,262 people residing in rural communities, the majority resided within 60 minutes of driving time to a center with computed tomography (85%), thrombolysis (81%), a stroke unit (68%), a stroke prevention clinic (74%), or inpatient rehabilitation (77.0%), but a much lower proportion (32%) were within 60 minutes of driving time to a center capable of providing endovascular thrombectomy (EVT). CONCLUSIONS: Most rural Ontario residents have appropriate geographic access to stroke services, with the exception of EVT. This information may be useful for jurisdictions seeking to optimize the regional organization of stroke care services.

Association of Physician Variation in Use of Manual Aspiration Thrombectomy With Outcomes Following Primary Percutaneous Coronary Intervention for ST-Elevation Myocardial Infarction: The National Cardiovascular Data Registry CathPCI Registry.

Importance: Following negative randomized clinical trials, US guidelines downgraded support for routine manual aspiration thrombectomy (AT) during primary percutaneous coronary intervention (pPCI) for ST-segment elevation myocardial infarction (STEMI). However, some PCI operators continue to endorse a clinical benefit with AT use despite the lack of supportive data. Objective: To examine temporal trends and comparative outcomes of AT use during pPCI for STEMI. Design, Setting, and Participants: Retrospective cohort study of the National Cardiovascular Data Registry (NCDR) CathPCI Registry from July 1, 2009, to June 30, 2016, to assess temporal trends and in-hospital outcomes associated with AT use. To evaluate outcomes through 180 days, a subanalysis was conducted among Centers for Medicare and Medicaid Services-linked patients from July 1, 2009, through December 31, 2014. The comparative effectiveness analysis was performed using instrumental variable analyses to account for treatment selection bias. The instrumental variable was operator's preference to use AT during pPCI. Data were analyzed between February 1, 2017, and April 1, 2018. Exposures: Aspiration thrombectomy use during pPCI for STEMI. Main Outcomes and Measures: Primary outcomes included in-hospital stroke and death. Secondary outcomes included heart failure, stroke, all-cause rehospitalization, and death through 180 days of follow-up. Results: Among all pPCIs performed (683 584), the mean (SD) age of patients was 61.7 (12.8) years, 489 257 were male (71.6%), and 596 384 were white (87.2%). Among patients undergoing pPCI, AT use increased from 2009 through 2011, with peak use of 13.8%. This was followed by a decline of more than 9%, reaching 4.7% by mid-2016. Overall, AT was used in 10.8% of pPCIs (lowest operator group median, 0%; highest operator group median, 33.8%). After instrumental variable analysis, AT use was associated with no difference in in-hospital death (adjusted absolute risk difference, -0.18%; 95% CI, -0.53% to 0.16%; P = .29) and a small increase in in-hospital stroke (adjusted RD, 0.14%; 95% CI, 0.01%-0.30%; P = .03). Among Centers for Medicare and Medicaid Services-linked patients, AT use was not associated with differences in death, heart failure, stroke, or rehospitalization at 180 days. Conclusions and Relevance: In this large, nationwide analysis, AT use during STEMI pPCI declined by more than 50% since 2011, with use as of mid-2016 at less than 5%. Selective AT use was associated with a small excess risk of in-hospital stroke and no difference in other outcomes through 180 days of follow-up.

Hemodialysis Access Maintenance in the Medicare Population: An Analysis Over a Decade of Trends by Provider Specialty and Site of Service.

PURPOSE: To evaluate annual national trends in hemodialysis access maintenance procedures in the Medicare population by specialty and setting. METHODS: Medicare Physician Supplier Procedure Summary Master Files between 2005 and 2015 were analyzed for procedure codes of hemodialysis access angiography and percutaneous thrombectomy. Using physician specialty codes, component procedure volume for endovascular services were queried for radiology, medicine, and surgery. Data entries were analyzed by provider specialty and place of service. Average submitted and allowed charges per intervention were extracted. Linear regression modeling was used to identify trends in number of and allowed charges by specialty and practice setting. RESULTS: Between 2005 and 2015, the frequency of dialysis access angiography for Medicare fee-for-service beneficiaries increased by a total of 74.71% (211,181 to 368,955). Specialty-specific analysis demonstrated volume increases of 220.21% (22,128 to 101,109) for surgery, 249.02% (32,690 to 114,094) for medicine, and 2.81% (135,564 to 139, 367) for radiology. By 2015, an increased trend from hospital-based to non-hospital-based procedures associated with significantly higher reimbursement rates to providers (+18,798 non-hospital-based cases/year, $46.95/year, P ≤ .001) was also observed, with medicine performing the highest volume of non-hospital-based procedures. In this period, there was also a modest total overall increase of percutaneous thrombectomy procedures by 7.75% (61,485 to 66,250). CONCLUSIONS: The frequency of endovascular hemodialysis access maintenance procedures in the Medicare fee-for-service program has increased from 2005 to 2015, with the majority market share transitioning from radiologists to non-radiologists. Similarly, most access maintenance in this time period changed from hospital-based to non-hospital-based interventions.

Socioeconomic disparities in the utilization of mechanical thrombectomy for acute ischemic stroke.

BACKGROUND: Previous studies have demonstrated that socioeconomic disparities in access to treatment of cerebrovascular diseases exist. We studied the Nationwide Inpatient Sample (NIS) to determine if disparities exist in utilization of mechanical thrombectomy for acute ischemic stroke. METHODS: Using the NIS for the years 2006-2010, we selected all discharges with a primary diagnosis of acute ischemic stroke. Patients who received mechanical thrombectomy for stroke were identified by using the International Classification of Diseases, Ninth Revision, procedure code 39.74. We examined the utilization rates of mechanical thrombectomy by race/ethnicity (white, black, Hispanic, and Asian/Pacific Islander), income quartile (first, second to third, and fourth), and insurance status (Medicare, Medicaid, self-pay, and private). We also studied thrombectomy utilization rates at hospitals that performed thrombectomy. RESULTS: From 2006 to 2010, 2,087,017 patients were hospitalized with a primary diagnosis of acute ischemic stroke; 8946 patients (.4%) received mechanical thrombectomy. Compared with white patients, black patients had significantly lower rates of overall mechanical thrombectomy utilization (odds ratio [OR] = .59, 95% confidence interval [CI] = .55-.64, P < .0001) and at centers that offered mechanical thrombectomy (OR = .44, 95% CI = .41-.47, P < .0001). Compared with patients in the highest income quartile, patients in the lowest income quartile had significantly lower rates of mechanical thrombectomy utilization both overall (OR = .66, 95% CI = .62-.70, P < .0001) and at centers that offered mechanical thrombectomy (OR = .80, 95% CI = .75-.84, P < .0001). Compared with patients with private insurance, self-pay patients had significantly lower mechanical thrombectomy utilization both overall (OR = .71, 95% CI = .64-.78, P < .0001) and at centers that offered mechanical thrombectomy (OR = .81, 95% CI = .74-.90, P < .0001). CONCLUSIONS: Significant socioeconomic disparities exist in the utilization of mechanical thrombectomy in the United States.

[Quality parameters in the treatment of acute stroke: comparison of various regional treatment concepts]. / Qualitätsparameter der akuten Schlaganfallversorgung: Gegenüberstellung unterschiedlicher regionaler Versorgungskonzepte.

BACKGROUND: The long-term prognosis of stroke patients is still dependent in particular on the timing of a correct diagnosis, immediate initiation of a suitable specific therapy and competent treatment in a stroke unit. Therefore, nationwide attempts are being made to establish a comprehensive coverage of the necessary specific competence and infrastructural requirements. Divergent regional circumstances and economic viewpoints determine the characteristics of the various healthcare concepts and the interplay between participating cooperation partners. This article compares the development with respect to three qualitative treatment parameters exemplified by four regional healthcare models during the time period 2008-2011. METHODS: The hospitalization rates for patients with transitory ischemic attacks, ischemic and hemorrhagic stroke, the case numbers for stoke unit treatment and the rates of systemic thrombolysis and mechanical thrombectomy in the regions of Berlin, the Ruhr Area, Ostwestfalen-Lippe and southeast Bayern (TEMPiS) are presented based on the data from the DRG statistical reports for the years 2008 and 2011. RESULTS: The average hospitalization rates for ischemic stroke patients (brain infarct ICD 163) in the time period from 2008 to 2011 were 294 per 100,000 inhabitants for the Ruhr Area, 257 per 100,000 inhabitants for Ostwestfalen-Lippe and 265 per 100,000 inhabitants each for Berlin and southeast Bayern. The complex stroke treatment quota for southeast Bayern in 2008 was 31 % and 47 % in 2011 and the respective quotas for the other regions studied were 42-44 % and 58-59 %. The rate of systemic thrombolysis in 2008 ranged between 4.2 % and 7.4 % and in 2011 the increase in the range for the 4 regions studied was between 41 % and 145 %. In 2011 the thrombectomy quota of 2 % in the Ruhr Area was the only one which was above the national average of 1.3 % of all brain infarcts. DISCUSSION: Stroke is a common disease in the four regions studied. For the established forms of therapy, complex treatment of stroke and systemic thrombolysis, the positive effect of structurally improved approaches in the four different regional treatment concepts could be confirmed during the course of the observational time period selected. Mechanical thrombectomy which is currently still considered to be an individual healing attempt, was used significantly more often in the Ruhr Area in 2011 than in the other three regions studied. A standardized referral procedure had previously been established in the metropolitan regions.

Is mechanical clot removal or disruption a cost-effective treatment for acute stroke?

BACKGROUND AND PURPOSE: It is unclear whether the costs and risks of mechanical therapies make them cost-effective. We examined whether interventions such as mechanical clot removal or disruption with angioplasty are cost-effective for acute ischemic stroke compared with best medical therapy. MATERIALS AND METHODS: We performed a cost-utility analysis of patients with acute stroke due to large intracranial artery occlusion presenting beyond the 3-hour window for IV tPA. Model inputs for the mechanical arm were derived from Multi MERCI trial data and a recent meta-analysis. For best medical therapy, we used rates of spontaneous recanalization, ICH, and functional outcomes based on a systematic literature review. Discounted QALYs were determined by using the Markov modeling for 65-year-old patients with acute ischemic stroke. RESULTS: On the basis of a systematic literature review, we modeled an 84% rate of recanalization with mechanical intervention and a 6.3% rate of symptomatic ICH. For best medical therapy, we modeled a spontaneous recanalization rate of 24% with a 2% rate of symptomatic ICH. Mechanical therapies were associated with a $7718 net cost and a gain of a 0.82 QALYs for each use, thus yielding a net of $9386/QALY gained. In sensitivity analyses, results were dependent on the rates of recanalization, symptomatic ICH rates, and costs of treatment. CONCLUSIONS: On the basis of available data, mechanical therapies in qualified patients with acute stroke beyond the window for IV tPA appear to be cost-effective. However, the inputs are not derived from randomized trials, and results are sensitive to several assumptions.

Prospective randomized comparison of surgical versus endovascular management of thrombosed dialysis access grafts.

PURPOSE: Salvage of thrombosed prosthetic dialysis shunts can be performed using surgical or endovascular techniques. A prospective randomized trial was designed to compare the efficacy of these two methods in restoring dialysis access function. METHODS: One hundred fifteen patients with thrombosed dialysis shunts were randomized prospectively to surgical (n = 56) or endovascular (n = 59) therapy. In the surgical group, salvage was attempted with thrombectomy alone in 22% and with thrombectomy plus graft revision in 78%. In the endovascular group, graft function was restored with mechanical (82%) or thrombolytic (18%) graft thrombectomy followed by percutaneous angioplasty. RESULTS: Stenosis limited to the venous anastomotic area was the cause of shunt thrombosis in 55% of patients, and long-segment venous outflow stenosis or occlusion was the cause in 30%. In 83% of the surgical group and in 72% of the endovascular group, graft function was immediately restored (p = NS). The postoperative graft function rate was significantly better in the surgical group (p < 0.05). Thirty-six percent of grafts managed surgically remained functional at 6 months and 25% at 12 months. In the endovascular group, 11% were functional at 6 months and 9% by 12 months. Patients with long-segment venous outflow stenosis or occlusion had a significantly worse patency rate than those with venous anastomotic stenosis (p < 0.05). CONCLUSIONS: Neither surgical nor endovascular management resulted in long-term function for the majority of shunts after thrombosis. However, surgical management resulted in significantly longer primary patency in this patient population, supporting its use as the primary method of management in most patients in whom shunt thrombosis develops.