Epidemiological patterns of tick-borne encephalitis in Lithuania and clinical features in adults in the light of the high incidence in recent years: a retrospective study.

BACKGROUND AND PURPOSE: Lithuania is one of the countries with the highest incidence of tick-borne encephalitis (TBE) in Europe. The aim of this study was to describe the epidemiological patterns of TBE in Lithuania, and characterize clinical features in adults in the light of the high incidence in recent years. METHODS: Surveillance data available on the website of the Centre for Communicable Diseases and AIDS of Lithuania were used to describe the epidemiological patterns of TBE. The retrospective study included 712 patients hospitalized in the Centre for Infectious Diseases and the Centre for Neurology of Vilnius University in the years 2005-2014. RESULTS: Tick-borne encephalitis incidence rates have been increasing by 8.5% per year for the 45-year period from 1970 to 2014. The joinpoint model finds two joinpoints at 1991 and 1994, with a significant decrease of 8.4% per year (P < 0.05) prior to the joinpoint at 1991, and a rise of 195.2% afterwards. TBE presented with meningoencephalitis in 556 cases (81.3%). A total of 129 patients (18%) had a severe case of the disease. The most common neurological signs were ataxia (579, 81.3%), meningeal signs (474, 66.5%) and tremor (338, 47.5%). Limb paresis was observed in 6.3% of patients. Five patients (0.7%) died, and 544 patients (76.7%) were discharged with sequelae. CONCLUSIONS: Intensified efforts in promoting TBE vaccination will be needed in the light of the high incidence and expanded spatial distribution. Significant prognostic factors for severe cases of the disease were age above 61 and delayed immune response of specific immunoglobulin G.

Clinical outcome of cardioembolic stroke treated by intravenous thrombolysis.

INTRODUCTION: Cardioembolic stroke (CS) in patients without thrombolytic treatment is associated with a worse clinical outcome and higher mortality compared to other types of stroke. The aim of this study was to determine the clinical outcome of CS in patients treated by intravenous thrombolysis (IVT). MATERIAL AND METHODOLOGY: Data of patients from the SITS-EAST register (Safe Implementation of Treatments in Stroke) were analyzed in patients who received IVT treatment from 2000 to April 2014. The effect of the stroke etiology according to ICD-10 classification on outcome was analyzed using a univariate and multivariate analysis. The outcomes were assessed as follows: excellent clinical outcome (modified Rankin scale (mRS) 0-1) at 3 months, the rate of symptomatic intracranial hemorrhage (sICH), mortality, and improvement at 24 hours after IVT. RESULTS: Data of 13 772 patients were analyzed. CS represented 30% of all strokes. The mean age of patients with CS, atherothrombotic stroke, lacunar stroke, and other stroke was 70.8, 66.7, 66.2, and 63.3 years, respectively (P < .001). Severity of stroke on admission by median NIHSS score was 13 points in patients with CS, 12 points - in atherothrombotic stroke, 7 points - in lacunar stroke, and 10 points-in other stroke types (P < .001). No difference in mortality was detected among atherothrombotic and CS; however, atherothrombotic strokes had higher odds of sICH [OR = 1.63 (95% CI: 1.07-2.47), P = .023], lower odds of early improvement [OR = 0.79 (95% CI: 0.72-0.86), P < .001], and excellent clinical outcome [OR = 0.77 (95% CI: 0.67-0.87), P < .001] compared with CS. CONCLUSIONS: Cardioembolic strokes are not associated with increased mortality. Patients with CS are less likely to have sICH and have better outcome after IVT.

Intravenous thrombolysis for patients with in-hospital stroke onset: propensity-matched analysis from the Safe Implementation of Treatments in Stroke-East registry.

BACKGROUND AND PURPOSE: Recent cross-sectional study data suggest that intravenous thrombolysis (IVT) in patients with in-hospital stroke (IHS) onset is associated with unfavorable functional outcomes at hospital discharge and in-hospital mortality compared to patients with out-of-hospital stroke (OHS) onset treated with IVT. We sought to compare outcomes between IVT-treated patients with IHS and OHS by analysing propensity-score-matched data from the Safe Implementation of Treatments in Stroke-East registry. METHODS: We compared the following outcomes for all propensity-score-matched patients: (i) symptomatic intracranial hemorrhage defined with the safe implementation of thrombolysis in stroke-monitoring study criteria, (ii) favorable functional outcome defined as a modified Rankin Scale (mRS) score of 0-1 at 3 months, (iii) functional independence defined as an mRS score of 0-2 at 3 months and (iv) 3-month mortality. RESULTS: Out of a total of 19 077 IVT-treated patients with acute ischaemic stroke, 196 patients with IHS were matched to 5124 patients with OHS, with no differences in all baseline characteristics (P > 0.1). Patients with IHS had longer door-to-needle [90 (interquartile range, IQR, 60-140) vs. 65 (IQR, 47-95) min, P < 0.001] and door-to-imaging [40 (IQR, 20-90) vs. 24 (IQR, 15-35) min, P < 0.001] times compared with patients with OHS. No differences were detected in the rates of symptomatic intracranial hemorrhage (1.6% vs. 1.9%, P = 0.756), favorable functional outcome (46.4% vs. 42.3%, P = 0.257), functional independence (60.7% vs. 60.0%, P = 0.447) and mortality (14.3% vs. 15.1%, P = 0.764). The distribution of 3-month mRS scores was similar in the two groups (P = 0.273). CONCLUSIONS: Our findings underline the safety and efficacy of IVT for IHS. They also underscore the potential of reducing in-hospital delays for timely tissue plasminogen activator delivery in patients with IHS.

Benefit of thrombolysis for stroke is maintained around the clock: results from the SITS-EAST Registry.

BACKGROUND AND PURPOSE: The outcome of thrombolysis for early morning and sleep time strokes may be worse because of uncertainty of stroke onset time or differences in logistics. The aim of the study was to analyze if stroke outcome after intravenous thrombolysis differs depending on time of day when the stroke occurs. METHODS: The data collected in the Safe Implementation of Treatments in Stroke - Eastern Europe (SITS-EAST) Registry between September 2000 and December 2011 were used. Strokes were categorized as night-time 00:00-07:59, day-time 08:00-15:59 and evening-time 16:00-23:59 and were compared in terms of several outcome measures. All results were adjusted for baseline differences. RESULTS: A total of 8878 patients were enrolled: 18% had night-time, 54% day-time and 28% evening-time strokes. Onset-to-treatment time in patients with night-time strokes was 10 min longer than in day-time and evening-time strokes (P < 0.001). Symptomatic intracerebral hemorrhage by ECASS II definition occurred in 5.6%, 5.6% and 5.3% (adjusted P = 0.41) of the night-time, day-time and evening-time stroke patients, respectively; by SITS definition it occurred in 2.5%, 1.9% and 1.3% (adjusted P = 0.013) and by NINDS definition in 7.8%, 7.6% and 7.5% (adjusted P = 0.74). Patients with night-time, day-time and evening-time strokes achieved modified Rankin Scale score 0-1 in 33%, 31%, 31% (adjusted P = 0.34) and 0-2 in 52%, 51%, 50% (adjusted P = 0.23), and 13%, 15%, 16% respectively of patients died (adjusted P = 0.17) by 3 months. CONCLUSIONS: The time when stroke occurs (day versus evening versus night) does not affect the outcome after thrombolysis despite the fact that patients with night-time strokes have worse time management.

Prevalence of micro-emboli in symptomatic high grade carotid artery disease: a transcranial Doppler study.

BACKGROUND AND PURPOSE: Echolucent carotid plaques, as well as downstream micro-embolisation, may be associated with an increased risk of stroke. However, the relationship between carotid plaque ultrasound characteristics and micro-embolic signals (MES) detected in the middle cerebral artery (MCA) is still controversial. The purpose of this study was to investigate the prevalence of MES in patients with symptomatic high-grade internal carotid artery (ICA) stenosis and to identify predisposing factors, such as plaque echogenicity and intra stenotic blood flow velocity pattern. METHODS: 197 patients (mean age 69.5+/-8.6, 161 males) with confirmed symptomatic high-grade ICA stenosis and anti-platelet treatment underwent bilateral MES monitoring for 30 minutes within the anterior circulation, using Power M-mode transcranial Doppler techniques (TCD). Carotid artery plaques were characterized by Gray-Weale scaling. RESULTS: In 32.0% of the patients, we detected MES by TCD within the MCA on the symptomatic side, but the same finding was made in only 4.5% on the corresponding asymptomatic site (p<0.0001). The presence or absence of MES was associated with neither ultrasonic plaque characteristics nor the intrastenotic blood flow velocities at peak systole and end diastole. The median time since the last ischemic event symptoms was shorter in the patient group with MES [+] than in MES [-] (p=0.013). CONCLUSIONS: Despite optimum standard anti-platelet therapy, cerebral micro-embolisation occurs in 30% of patients with symptomatic carotid artery disease, which might therefore be a possible risk factor for recurrent neurological symptoms. However, the presence of MES is independent of intrastenotic blood flow disturbances and grey scale ultrasound plaque characteristics. The presence of MES as an indicator of unstable plaque and thereby a possible risk factor for stroke should be evaluated prospectively using various algorithms for plaque classifications.

Evaluation of posterior cerebral artery blood flow with transcranial Doppler sonography: value and risk of common carotid artery compression.

PURPOSE: Investigations of the posterior cerebral arteries (PCA) by transcranial Doppler sonography (TCD) may be less reliable than investigations of the anterior part of the circle of Willis. Nevertheless, a true PCA may be identified by manual compression of the proximal common carotid artery (CCA) during TCD. Therefore, we used CCA compression in clinically indicated TCD studies and assessed retrospectively its risks and prospectively its benefits for PCA evaluations. METHODS: Using the transtemporal approach, we prospectively assessed flow velocities in posteriorly located blood vessels in 180 consecutive patients before and during CCA compression. The complications of CCA compression were retrospectively reviewed in all 3,383 clinical TCD investigations performed over an 8-year period. RESULTS: Decreased flow velocities during ipsilateral CCA compression occurred in 17% of patients. A PCA-like vessel with perfusion from the carotid artery or PCA supply from the carotid circulation was unmasked. Mixed distal PCA support by the posterior communicating artery and proximal PCA could not be shown by TCD. Transient cerebral symptoms occurred in less than 0.4% of the 3,383 retrospectively reviewed TCD investigations; no other adverse effects were seen. CONCLUSIONS: TCD without CCA compression may lead to false identification of the PCA. Since transient cerebral symptoms during CCA compression are rare, CCA compression can be used when a clinical TCD investigation of intracranial collateral blood flow compensation is indicated or when the identification of a cerebral artery is uncertain.

Middle cerebral artery circulation during carotid surgery. A transcranial Doppler study.

OBJECTIVE: Perioperative carotid cross-clamping might induce low stump pressures as well as hypoperfusion of the middle cerebral artery. In this study blood flow velocities in the middle cerebral artery were compared with intraoperative measurements of the poststenotic carotid blood pressure. DESIGN: Forty-one patients with internal carotid artery stenosis were operated on without shunting, under general anesthesia. Poststenotic carotid pressures and middle cerebral artery flow velocities were measured before and during cross-clamping. The hemodynamic responses to preoperative carotid compressions and intraoperative cross-clamping were evaluated. RESULTS: In seven patients the poststenotic carotid blood pressure decreased on clamping despite unchanged or even increased middle cerebral artery blood flow velocities. In all other patients, pressure changes were significantly correlated to the decrease in middle cerebral artery blood flow velocities. Autoregulatory blood flow velocity responses after preoperative common carotid artery compression were not reproducible by cross-clamping. CONCLUSIONS: Stump blood pressure measurements may not reflect middle cerebral artery perfusion in about 20% of thrombendarterectomies performed under general anesthesia. A possible explanation might be dimished cerebral autoregulation and changes in collateral flow distributions.