Aneurysm morphology in patients with autosomal dominant polycystic kidney disease: A case-control study.

PURPOSE: Approximately 8% of patients with autosomal dominant polycystic kidney disease (ADPKD) develop intracranial aneurysms. The reason for development of intracranial aneurysms in ADPKD patients might be related to interactions between the presence of hypertension and the basic mechanism underlying the disease, which leads to weakness of the connective tissue. In this study, we aimed to identify differences in aneurysm morphology between ADPKD patients and a location-matched set of controls. METHODS: A total of 42 ADPKD patients and 49 control patients with 122 aneurysms were included. Aneurysm size, location, and morphology were evaluated by two neuroradiologists. Aneurysm morphology was classified into one of three groups: regular saccular, irregular saccular, and fusiform. Continuous variables were compared with chi-squared tests and categorical variables were compared with student's t-test. RESULTS: When considering all patients, there was no significant difference in aneurysm morphology or size (4.5 ±â€¯2.6 mm vs 5.4 ±â€¯2.9 mm; p = 0.09) between the ADPKD and control group. In a subgroup analysis of medium and large aneurysms (n = 61), there was a significantly lower incidence of regular saccular aneurysms (28% vs. 56%; p = 0.03) and higher incidence of fusiform aneurysms (12% vs 0%; p = 0.03) in the ADPKD group compared to a control group. CONCLUSION: When excluding categorically "small" aneurysms, there is a reduced incidence of regular saccular aneurysms and increased incidence of fusiform aneurysms in ADPKD patients compared to a control group. Further study of this population of patients is warranted to better understand their risks of aneurysm rupture and indications for treatment.

Wingspan stent delivery catheter fracture and the TRAP technique for endovascular salvage.

Background Intracranial atherosclerotic disease may result in ischemic infarction and has a high rate of recurrent ischemic strokes despite medical therapy. Patients who fail medical therapy may undergo endovascular treatment with cerebral artery angioplasty and possible Wingspan stent placement. We present a unique case of Wingspan delivery microcatheter fracture that resulted in a retained foreign body and an endovascular salvage maneuver. Case description An elderly patient presented with an acute ischemic stroke due to a severe stenosis in the proximal left middle cerebral artery (MCA). The patient failed non-invasive medical treatment and underwent endovascular treatment with angioplasty and Wingspan stent placement. Following Wingspan stent deployment, the stent delivery catheter fractured, and the retained catheter fragment resulted in MCA occlusion. The foreign body was retrieved by balloon catheter inflation within an intermediate catheter adjacent to the proximal end of the fractured catheter and removal of the entire construct (TRAP technique). Conclusions Wingspan delivery microcatheter fracture is a rare event. The TRAP technique may be used for successful retrieval of a retained foreign body.

Capillary Index Score in acute ischemic stroke: interobserver reliability and correlation with neurological outcomes.

BACKGROUND: Collateral blood flow has been identified as a possible factor to evaluate when predicting neurological outcomes or selecting patients for endovascular therapy in acute ischemic stroke. The Capillary Index Score (CIS) has recently been proposed as a tool to select patients with sufficient collateral blood flow for vascularization and to predict good neurological outcomes. We investigated the inter-rater agreement among reviewers of CIS and compared consensus scores to neurological outcomes. METHODS: We conducted a retrospective review of 29 randomly selected patients undergoing endovascular therapy for an occlusion in the middle cerebral artery or intracranial internal carotid artery. Patients' angiograms were reviewed by four reviewers of varying experience levels and given a CIS ranging from 0-3. A favorable CIS was 2 or 3 and an unfavorable CIS was 0 or 1. The inter-agreement of the reviewers was calculated using the κ statistic. A consensus CIS was compared with good neurological outcome, defined as modified Rankin Scale scores (mRS≤2) at 90 days. RESULTS: The agreement between reviewers for the CIS ranged from κ=0.66-0.97, indicating good to very good agreement. 92% of patients with favorable CIS had a positive neurological outcome compared to only 14% of unfavorable CIS patients. The number of patients with a favorable neurological outcome (mRS≤2) at 90 days was higher in the favorable CIS group (P<0.0001). CONCLUSIONS: CIS was a reproducible metric among physicians of varying experiences. Favorable CIS scores were a predictor of good neurological outcome and lower rates of intracranial hemorrhage. We believe that the Capillary Index Score can be used alongside other tools to improve patient selection for endovascular treatment.

A data-driven approach for addressing the lack of flow waveform data in studies of cerebral arterial flow in older adults.

OBJECTIVE: Blood flow waveforms-essential data for hemodynamic modeling-are often in practice unavailable to researchers. The objectives of this work were to assess the variability among the waveforms for a clinically relevant older population, and develop data-based methods for addressing the missing waveform data for hemodynamic studies. APPROACH: We analyzed 272 flow waveforms from the internal carotid arteries of older patients (73 ± 13 yr) with moderate cardiovascular disease, and used these data to develop methods to guide new approaches for hemodynamic studies. MAIN RESULTS: Profound variations in waveform parameters were found within the aged population that were not seen in published data for young subjects. Common features in the aged population relative to the young included a larger systole-to-diastole flow rate ratio, increased flow during late systole, and absence of a dicrotic notch. Eight waveforms were identified that collectively represent the range of waveforms in the older population. A relationship between waveform shape and flow rate was obtained that, in conjunction with equations relating flow rate to diameter, can be used to provide individualized waveforms for patient-specific geometries. The dependence of flow rate on diameter was statistically different between male and female patients. SIGNIFICANCE: It was shown that a single archetypal waveform cannot well-represent the diverse waveforms found within an aged population, although this approach is frequently used in studies of flow in the cerebral vasculature. Motivated by these results, we provided a set of eight waveforms that can be used to assess the hemodynamic uncertainty associated with the lack of patient-specific waveform data. We also provided a methodology for generating individualized waveforms when patient gender, age, and cardiovascular disease state are known. These data-driven approaches can be used to devise more relevant in vitro or in silico intra-cranial hemodynamic studies for older patients.

Correlation between clot density and recanalization success or stroke etiology in acute ischemic stroke patients.

Background Predicting recanalization success for patients undergoing endovascular treatment for acute ischemic stroke is of significant interest. Studies have previously correlated the success of recanalization with the density of the clot. We evaluated clot density and its relationship to revascularization success and stroke etiology. Methods We conducted a retrospective review of 118 patients undergoing intra-arterial therapy for acute ischemic stroke. Mean and maximum thrombus density was measured by drawing a circular region of interest on an axial slice of a non-contrast computed tomography scan. T-tests were used to compare clot density to recanalization success or to stroke etiology, namely large artery atherosclerosis and cardioembolism. Recanalization success was compared in four device groups: aspiration, stent retriever, aspiration and stent retriever, and all other. Results There was no significant difference in the mean clot density in patients with successful ( n = 80) versus unsuccessful recanalization ( n = 38, 50.1 ± 7.4 Hounsfield unit (HU) vs. 53 ± 12.7 HU; P = 0.17). Comparing the large artery thromboembolism ( n = 35) to the cardioembolic etiology group ( n = 56), there was no significant difference in mean clot density (51.5 ± 7.7 HU vs. 49.7 ± 8.5 HU; P = 0.31). A subgroup analysis of middle cerebral artery occlusions ( n = 65) showed similar, non-statistically significant differences between groups. There was no difference in the rate of recanalization success in patients with a mean clot density greater than 50 HU or less than 50 HU in each of the four device groups. Conclusions There was no relationship between clot density and revascularization success or stroke etiology in our study. More research is needed to determine if clot density can predict recanalization rates or indicate etiology.

Capillary Index Score and Correlation with Outcomes in Acute Ischemic Stroke: A Meta-analysis.

BACKGROUND AND PURPOSE: The capillary index score (CIS) has been recently introduced as a metric for rating the collateral circulation of ischemic stroke patients. Multiple studies in the last five years have evaluated the correlation of good CIS with clinical outcomes and suggested the use of CIS in selecting patients for endovascular treatment. We performed a meta-analysis of these studies comparing CIS with clinical outcomes. METHODS: We conducted a computerized search of three databases from January 2011 to November 2015 for studies related to CIS and outcomes. A CIS = 0 or 1 is considered poor (pCIS) and a CIS = 2 or 3 is considered favorable (fCIS). Using random-effect meta-analysis, we evaluated the relationship of CIS to neurological outcome (modified Rankin scale score ≤ 2), recanalization, and post-treatment hemorrhage. Meta-regression analysis of good neurological outcome was performed for adjusting baseline National Institutes of Health Stroke Scale (NIHSS) between groups. RESULTS: Six studies totaling 338 patients (212 with fCISs and 126 with pCISs) were included in the analysis. Patients with fCIS had higher likelihood of good neurological outcome [relative risk (RR) = 3.03; confidence interval (CI) = 95%, 2.05-4.47; p < 0.001] and lower risk of post-treatment hemorrhage (RR = 0.38; CI = 95%, 0.19-0.93; p = 0.04) as compared with patients in the pCIS group. When adjusting for baseline NIHSS, patients with fCIS had higher RR of good neurological outcome when compared with those with pCIS (RR = 2.94; CI = 95%, 1.23-7, p < 0.0001). Favorable CIS was not associated with higher rates of recanalization. CONCLUSIONS: Observational evidence suggests that acute ischemic stroke patients with fCIS may have higher rates of good neurological outcomes compared with patients with pCIS, independent of baseline NIHSS. CIS may be used as another tool to select patients for endovascular treatment of acute ischemic stroke.

Hemodynamics during anesthesia for intra-arterial therapy of acute ischemic stroke.

BACKGROUND AND PURPOSE: Many studies have suggested a relationship between the type of anesthesia provided during intra-arterial therapy for acute ischemic stroke and patient outcomes. Variability in blood pressure and hypotension have previously been identified as possible reasons for worse outcomes in acute stroke. Our aim was to investigate hemodynamic parameters and neurological outcomes of patients receiving either general anesthesia or conscious sedation for intra-arterial therapy of acute stroke. METHODS: We performed a retrospective review of patients undergoing intra-arterial therapy from December 2008 to March 2015. Demographic data, baseline National Institutes of Health Stroke Scale score, preoperative physiological variables, procedural details, systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), heart rate, and modified Rankin Scale scores were recorded. RESULTS: 99 patients were included in the study, with 38 receiving general anesthesia and 61 receiving conscious sedation. Patients who received general anesthesia had a lower maximum SBP (p=0.02), minimum SBP (p<0.0001), minimum DBP (p<0.0001), and minimum MAP (p<0.0001). On multivariate analysis, general anesthesia was associated with lower minimum SBP (p=0.04), DBP (p=0.02), and MAP (p=0.007). Conscious sedation was associated with more favorable neurological outcomes (p=0.02). Patients with favorable neurological outcomes had a lower maximum variability in SBP (p=0.01) and MAP (p=0.03), as well as a higher minimum DBP (p=0.03). CONCLUSIONS: Patients with acute ischemic stroke undergoing intra-arterial therapy with general anesthesia had lower minimum SBP, DBP, and MAP, greater fluctuations in blood pressure, and less favorable outcomes. More studies are needed to examine the implications of variable and reduced blood pressures and neurological outcomes.