Routine surveillance of pelvic and lower extremity deep vein thrombosis in stroke patients with patent foramen ovale.

Patent foramen ovale (PFO) is a potential conduit for paradoxical embolization to the systemic atrial circulation of a thrombus originating in the venous system. In a selected group of subjects, the prevalence of deep vein thrombosis (DVT) was assessed. Subjects were identified if they underwent magnetic resonance venography (MRV) pelvis and lower extremity doppler (LE-VDU) for assessment of DVT with PFO. The primary outcome measure was to report the number of patients with paradoxical embolization as their suspected etiology of stroke due to the presence of DVT, which then will be considered as determined stroke. Others with determined stroke diagnosis were reported using Treatment of Acute Stroke Trial (TOAST) criteria. At discharge, those without etiology of their stroke were grouped under embolic stroke of undetermined source (ESUS). We further analyzed the prevalence of DVT by age group, ≤ 60 years vs > 60 years to describe if the prevalence is higher with younger age and to evaluate if higher Risk of Paradoxical Embolism (ROPE) score will have higher number of DVTs compared to lower ROPE scores. Of the 293, 19 (7%) were strokes due to paradoxical embolism. At discharge, determined stroke were 54% vs ESUS were 46%. The overall prevalence of DVT was 19 (7%); MRV-pelvis 13 (4%), and LE-VDU was 9 (3%). No significant difference was noted using both modalities. However, in multivariable regression analysis, a trend suggested an association between pelvic thrombi and high ROPE score as the etiology of stroke; OR 3.56 (0.98, 12.93); p = 0.054. Detection of DVT was not associated with PFO, high ROPE scores or young age. Our data indicate an over-reliance of testing for DVT, particularly MRV pelvis with contrast, in patients with PFO. Clinical studies are needed to identify other factors predictive of DVT in patients with ischemic stroke and PFO.

Endovascular Thrombectomy for Mild Strokes: How Low Should We Go?

Background and Purpose- Endovascular thrombectomy (EVT) is effective for acute ischemic stroke with large vessel occlusion and National Institutes of Health Stroke Scale (NIHSS) ≥6. However, EVT benefit for mild deficits large vessel occlusions (NIHSS, <6) is uncertain. We evaluated EVT efficacy and safety in mild strokes with large vessel occlusion. Methods- A retrospective cohort of patients with anterior circulation large vessel occlusion and NIHSS <6 presenting within 24 hours from last seen normal were pooled. Patients were divided into 2 groups: EVT or medical management. Ninety-day mRS of 0 to 1 was the primary outcome, mRS of 0 to 2 was the secondary. Symptomatic intracerebral hemorrhage was the safety outcome. Clinical outcomes were compared through a multivariable logistic regression after adjusting for age, presentation NIHSS, time last seen normal to presentation, center, IV alteplase, Alberta Stroke Program early computed tomographic score, and thrombus location. We then performed propensity score matching as a sensitivity analysis. Results were also stratified by thrombus location. Results- Two hundred fourteen patients (EVT, 124; medical management, 90) were included from 8 US and Spain centers between January 2012 and March 2017. The groups were similar in age, Alberta Stroke Program early computed tomographic score, IV alteplase rate and time last seen normal to presentation. There was no difference in mRS of 0 to 1 between EVT and medical management (55.7% versus 54.4%, respectively; adjusted odds ratio, 1.3; 95% CI, 0.64-2.64; P=0.47). Similar results were seen for mRS of 0 to 2 (63.3% EVT versus 67.8% medical management; adjusted odds ratio, 0.9; 95% CI, 0.43-1.88; P=0.77). In a propensity matching analysis, there was no treatment effect in 62 matched pairs (53.5% EVT, 48.4% medical management; odds ratio, 1.17; 95% CI, 0.54-2.52; P=0.69). There was no statistically significant difference when stratified by any thrombus location; M1 approached significance ( P=0.07). Symptomatic intracerebral hemorrhage rates were higher with thrombectomy (5.8% EVT versus 0% medical management; P=0.02). Conclusions- Our retrospective multicenter cohort study showed no improvement in excellent and independent functional outcomes in mild strokes (NIHSS, <6) receiving thrombectomy irrespective of thrombus location, with increased symptomatic intracerebral hemorrhage rates, consistent with the guidelines recommending the treatment for NIHSS ≥6. There was a signal toward benefit with EVT only in M1 occlusions; however, this needs to be further evaluated in future randomized control trials.

Acute splenic responses in patients with ischemic stroke and intracerebral hemorrhage.

Animal models provide evidence of spleen mediated post-stroke activation of the peripheral immune system. Translation of these findings to stroke patients requires estimation of pre-stroke spleen volume along with quantification of its day-to-day variation. We enrolled a cohort of 158 healthy volunteers and measured their spleen volume over the course of five consecutive days. We also enrolled a concurrent cohort of 158 stroke patients, measured initial spleen volume within 24 h of stroke symptom onset followed by daily assessments. Blood samples for cytokine analysis were collected from a subset of patients. Using data from healthy volunteers, we fit longitudinal quantile regression models to construct gender and body surface area based normograms of spleen volume. We quantified day-to-day variation and defined splenic contraction. Based on our criteria, approximately 40% of stroke patients experienced substantial post-stroke reduction in splenic volume. African Americans, older patients, and patients with past history of stroke have significantly higher odds of post-stroke splenic contraction. All measured cytokine levels were elevated in patients with splenic contraction, with significant differences for interferon gamma, interleukin 6, 10, 12, and 13. Our work provides reference standards for further work, validation of pre-clinical findings, and characterization of patients with post-stroke splenic contraction.