Amir Shaban

Circle of Willis Variants: Fetal PCA

We sought to determine the prevalence of fetal posterior cerebral artery (fPCA) and if fPCA was associated with specific stroke etiology and vessel territory affected. This paper is a retrospective review of prospectively identified patients with acute ischemic stroke from July 2008 to December 2010. We defined complete fPCA as absence of a P1 segment linking the basilar with the PCA and partial fPCA as small segment linking the basilar with the PCA. Patients without intracranial vascular imaging were excluded. We compared patients with complete fPCA, partial fPCA, and without fPCA in terms of demographics, stroke severity, distribution, and etiology and factored in whether the stroke was ipsilateral to the fPCA. Of the 536 included patients, 9.5% (n = 51) had complete fPCA and 15.1% (n = 81) had partial fPCA. Patients with complete fPCA were older and more often female than partial fPCA and no fPCA patients, and significant variation in TOAST classification was detected across groups (P = 0.023). Patients with complete fPCA had less small vessel and more large vessel strokes than patients with no fPCA and partial fPCA. Fetal PCA may predispose to stroke mechanism, but is not associated with vascular distribution, stroke severity, or early outcome.

New Model for Predicting Surgical Feeding Tube Placement in Patients With an Acute Stroke Event

Background and Purpose— The need for surgical feeding tube placement after acute stroke can be uncertain and associated with further morbidity. Methods— Retrospective data were recorded and compared across patients with acute ischemic stroke and intracerebral hemorrhage. We identified all feeding tubes placed as percutaneous endoscopic gastrostomy (PEG) tubes. A prediction score for PEG tube placement was developed separately for patients with acute ischemic stroke and intracerebral hemorrhage using logistic regression models of variables known by 24 hours from admission. Results— Of 407 patients included, 51 (12.5%) underwent PEG tube placement (25 acute ischemic stroke and 26 intracerebral hemorrhage). The odds of a patient with acute ischemic stroke with PEG score ≥3 of getting a PEG are greater than those with PEG score <3 (odds ratio, 15.68; 95% confidence interval, 4.55–54.01). The odds of a patient with intracerebral hemorrhage with PEG score ≥3 of getting a PEG are greater than those with PEG score <3 (odds ratio, 12.49; 95% confidence interval, 1.54–101.29). Conclusions— The PEG score, comprised by variables known within the first day of admission, may be a powerful predictor of PEG placement in patients with acute stroke.

Von Willebrand Factor Drives the Association Between Elevated Factor VIII and Poor Outcomes in Patients With Ischemic Stroke

Background and Purpose— Despite clear roles of factor VIII (FVIII) and von Willebrand factor (vWF) in thrombosis, few studies have examined the relationship of these factors with acute ischemic stroke (AIS). We sought to determine whether concurrent elevation in FVIII and vWF was associated with adverse events and outcomes. Methods— From our prospective stroke registry, patients consecutively admitted with AIS between July 2008 and October 2013 were included if both FVIII and vWF were measured during admission. The primary outcome was the modified Rankin Scale score on discharge. Results— Among 1453 cases in our stroke registry, 148 patients with AIS met inclusion criteria; 62 patients (41.9%) had FVIII−/vWF−, 16 patients (10.8%) had FVIII+/vWF−, and 51 patients (34.5%) had FVIII+/vWF+. In the fully adjusted model, patients with FVIII+/vWF+ had increased odds of inpatient complications (odds ratio, 8.6; 95% confidence interval, 1.58–46.85; P=0.013) and neuroworsening (odds ratio, 3.2; 95% confidence interval, 1.18–8.73; P=0.022) than patients with FVIII−/vWF−. Adjusted for age, baseline stroke severity, and glucose, patients with FVIII+/vWF+ had increased odds of poor functional outcome (modified Rankin Scale>2; odds ratio, 2.87; 95% confidence interval, 1.16–7.06; P=0.021) than patients with FVIII−/vWF−. Conclusions— Concurrent FVIII/vWF elevation predicts higher odds of inpatient complications, neuroworsening, and worse functional outcomes for patients with AIS compared with patients with normal levels. Our findings suggest that FVIII and vWF levels may serve as clinically useful stroke biomarkers by providing risk profiles for patients with AIS.

Hospital-Acquired Infection Underlies Poor Functional Outcome in Patients with Prolonged Length of Stay

Introduction Prolonged length of stay (pLOS) following ischemic stroke inflates cost, increases risk for hospital-acquired complications, and has been associated with worse prognosis. Methods Acute ischemic stroke patients admitted between July 2008 and December 2010 were retrospectively analyzed for pLOS, defined as a patient stable for discharge hospitalized for an additional ≥24 hours. Results Of 274 patients included, 106 (38.7%) had pLOS (median age 65 years, 60.6% female, 69.0% black). Patients with pLOS had higher admission NIHSS than patients without pLOS (9 versus 5, P = 0.0010). A larger proportion of patients with pLOS developed an infection (P < 0.0001), and after adjusting for covariates, these patients had greater odds of poor short-term functional outcome (OR = 2.25, 95% CI 1.17–4.32, P = 0.0148). Adjusting for infection, the odds of patients with pLOS having poor short-term functional outcome were no longer significant (OR = 1.68, 95% CI 0.83–3.35, P = 0.1443). Conclusions The contraction of a hospital-acquired infection was a significant predictor of pLOS and a contributor of poor short-term outcome following an ischemic stroke. Whether the cause or the consequence of pLOS, hospital-acquired infections are largely preventable and a target for reducing length of stay.

The Impact of Absent A1 Segment on Ischemic Stroke Characteristics and Outcomes

BACKGROUND A1 segment is the proximal portion of anterior cerebral artery. Absence of the A1 segment can compromise anterior cerebral collateral blood flow. Few studies have examined the association of an absent A1 segment and ischemic stroke outcome. We sought to determine the association between A1 absence and affected vessel territory, stroke volume, and outcomes among patients with acute ischemic stroke (AIS). METHODS A retrospective review of prospectively identified patients with AIS from July 2008 to March 2013 was performed. Patients without intracranial vascular imaging were excluded. We compared patients with absent A1 to patients with bilateral A1 segments in terms of demographics, stroke severity (as measured by National Institute of Health Stroke Scale [NIHSS]), vascular distribution, and in-hospital mortality using the chi-square test and logistic regression. RESULTS Of the 1146 patients with AIS and intracranial vascular imaging, 5.9% patients (n = 68) had absent A1. Compared with other AIS patients, those with absent A1 were older (65 vs. 63 years old, respectively, P = .016). There was no difference between groups in terms of the vascular distribution or the side of the stroke. The median volume of the infracted tissue was similar across the groups even when it was stratified according to the Treatment of Acute Stroke Trial classification. Patients with an absent A1 had twice higher odds of in-hospital mortality (odds ratio, 2.4; 95% confidence interval, 1.1-5.2; P = .028); however, significance was lost after adjusting to age, NIHSS at baseline, and glucose on admission. Other outcome measures were similar across the groups. CONCLUSIONS In our sample, patients with an absent A1 segment did not have a specific vascular distribution, larger infarct volume, or worse outcomes.

A Model for Predicting Persistent Elevation of Factor VIII among Patients with Acute Ischemic Stroke.

BACKGROUND AND PURPOSE Elevated levels of coagulation factor VIII (FVIII) may persist independent of the acute-phase response; however, this relationship has not been investigated relative to acute ischemic stroke (AIS). We examined the frequency and predictors of persistently elevated FVIII in AIS patients. METHODS AIS patients admitted between July 2008 and May 2014 with elevated baseline FVIII levels and repeat FVIII levels drawn for more than 7 days postdischarge were included. The patients were dichotomized by repeat FVIII level for univariate analysis at 150% and 200% activity thresholds. An adjusted model was developed to predict the likelihood of persistently elevated FVIII levels. RESULTS Among 1616 AIS cases, 98 patients with elevated baseline FVIII had repeat FVIII levels. Persistent FVIII elevation was found in more than 75% of patients. At the 150% threshold, the prediction score ranged from 0 to 7 and included black race, female sex, prior stroke, hyperlipidemia, smoking, baseline FVIII > 200%, and baseline von Willebrand factor (vWF) level greater than 200%. At the 200% threshold, the prediction score ranged from 0-5 and included female sex, prior stroke, diabetes mellitus, baseline FVIII level greater 200%, and baseline vWF level greater than 200%. For each 1-point increase in score, the odds of persistent FVIII at both the 150% threshold (odds ratio [OR] = 10.4, 95% confidence interval [CI] 1.63-66.9, P = .0134) and 200% threshold (OR = 10.2, 95% CI 1.82-57.5, P = .0083) increased 10 times. CONCLUSION Because an elevated FVIII level confers increased stroke risk, our model for anticipating a persistently elevated FVIII level may identify patients at high risk for recurrent stroke. FVIII may be a target for secondary stroke prevention.

Social History Matters-The Impact of Illicit Drug Use on tPA Use and In-Hospital Mortality in Acute Ischemic Stroke

Aims The objective of this descriptive study was to compare time to medical evaluation, intravenous tissue plasminogen activator (IV tPA) use, and short-term outcomes in illicit drug users compared to non-users presenting with acute ischemic stroke (AIS). Study Design This is a retrospective study performed from our stroke registry using deidentified patient information. Place and Duration of Study Tulane Medical Center Primary Stroke Center (PSC). Consecutive AIS patients presenting to our PSC from July 2008 to December of 2010 were identified from our prospectively collected stroke registry. Methodology Patients were categorized as toxicology positive (TP) or toxicology negative (TN). We compared baseline characteristics, clinical presentation, tPA use, and short-term outcomes in TP and TN patients. Results Two hundred and sixty-three patients met inclusion criteria (median age 63, 35.4% female, 66.5% Black). Nearly 40% of toxicology screens were positive. Stroke severity was similar with the median National Institute of Health Stroke Scale (NIHSS) of 6 in both groups; however, a higher proportion of TN patients were treated with IV tPA (32.1% vs. 21.2%). After adjustment for time from last seen normal to emergency department arrival (LSN-to-ED arrival), the odds of being treated with tPA for TP patients were similar to TN patients (OR 0.69, 95% CI 0.36–1.31, p=0.255). After adjustment for age, NIHSS, glucose, and tPA, the odds of in-hospital mortality in TP patients was 3 times that of TN patients (OR 3.17, 95% CI 1.07–9.43, p=0.038). Conclusion We found that the disparities observed in tPA use were attenuated after adjustment for time from LSN-to-ED arrival, suggesting an area for future intervention. Additionally, we found that TP patients may be at higher risk for in-hospital mortality. Further study on the role of substance abuse in time to ED arrival, tPA use, and outcome in AIS patients is warranted.

Safety and Efficacy of Acute Clopidogrel Load in Patients with Moderate and Severe Ischemic Strokes

Objective. To study the safety and efficacy of a clopidogrel loading dose in patients with moderate and severe acute ischemic strokes. Background. The safety of clopidogrel loading has been extensively investigated in patients with minor strokes and transient ischemic attacks. Methods. Acute ischemic stroke patients presenting consecutively to our center from 07/01/08 to 07/31/13 were screened. Clopidogrel loading was defined as at least 300 mg dose (with or without aspirin) given within 6 hours of admission. We compared outcomes in patients with baseline NIHSS > 3 with and without clopidogrel loading. Results. Inclusion criteria were met for 1011 patients (43.6% females, 69.1% black, median age 63). Patients with clopidogrel loading had lower baseline NIHSS than patients who were not loaded (8 versus 9, p = 0.005). The two groups had similar risk for hemorrhagic transformation (p = 0.918) and symptomatic hemorrhage (p = 0.599). Patients who were loaded had a lower rate of neurological worsening (38.9% versus 48.3%, p = 0.031) and less in-hospital mortality (4.3% versus 13.4%, p = 0.001) compared to those who were not loaded. The likelihood of having a poor functional outcome did not differ between the two groups after adjusting for NIHSS on admission (OR = 0.71, 95% CI 0.4633–1.0906, p = 0.118). Conclusion. Clopidogrel loading dose was not associated with increased risk for hemorrhagic transformation or symptomatic intracranial hemorrhage in our retrospective study and was associated with reduced rates of neuroworsening following moderate and severe stroke.

Left Atrial Enlargement on Transthoracic Echocardiography Predicts Left Atrial Thrombus on Transesophageal Echocardiography in Ischemic Stroke Patients

Background. Transesophageal echocardiogram (TEE) is superior to transthoracic echocardiogram (TTE) in detecting left atrial thrombus (LAT), a risk factor for stroke, but is costly and invasive, carrying a higher risk for complications. Aims. To determine the utility of using left atrial enlargement (LAE) on TTE to predict LAT on TEE. Methods. AIS patients who presented in 06/2008–7/2013 and underwent both TTE and TEE were identified from our prospective stroke registry. Analysis consisted of multivariate logistic regression with propensity score adjustment and receiver operating characteristic (ROC) area under the curve (AUC) analyses. Results. 219 AIS patients underwent both TTE and TEE. LAE on TTE was detected in 113 (51.6%) of AIS patients. Patients with LAE on TTE had higher proportion of LAT on TEE (8.4% versus 1.0%, p = 0.018). LAE on TTE predicted increased odds of LAT on TEE (OR = 8.83, 95% CI 1.04–74.83, p = 0.046). The sensitivity and specificity for LAT on TEE by LAE on TEE were 88.89% and 52.20%, respectively (AUC = 0.7054, 95% CI 0.5906–0.8202). Conclusions. LAE on TTE can predict LAT detected on TEE in nearly 90% of patients. This demonstrates the utility of LAE on TTE as a potential screening tool for LAT, potentially limiting unneeded costs and complications associated with TEE.

Recurrent posterior strokes in inflammatory bowel disease patients.

Objective. To describe the stroke characteristics of patients with a history of inflammatory bowel disease (IBD). Background. A hypercoagulable state associated with IBD has been frequently implicated as a risk factor for ischemic stroke. Variable mechanisms and infrequent occurrence limit prospective clinical research on the association between IBD and stroke. Methods. We retrospectively reviewed consecutive patients with acute ischemic stroke presenting to our medical center from 7/2008 to 9/2013. Patients with a history of IBD were identified. Clinical variables were abstracted from our prospective stroke registry. Results. Over the period of five years we identified only three patients with a documented history of IBD. Each of these patients presented three times to our hospital with new strokes. Patients presented outside the window for intravenous tPA treatment on 8/9 admissions. Each one of our patients had posterior strokes on at least two separate occasions. Hypercoagulation panel showed elevated factor VIII with or without concomitant elevation of Von Willebrand factor (vWF) during almost every admission (8/9 admissions). Only one admission was associated with IBD flare. Conclusion. The association between IBD and posterior strokes is a novel finding. Factor VIII elevation may serve as a biomarker of a peristroke hypercoagulable state in patients with IBD.