Imaging markers of small vessel disease and brain frailty, and outcomes in acute stroke.

OBJECTIVE: To assess the association of baseline imaging markers of cerebral small vessel disease (SVD) and brain frailty with clinical outcome after acute stroke in the Efficacy of Nitric Oxide in Stroke (ENOS) trial. METHODS: ENOS randomized 4,011 patients with acute stroke (<48 hours of onset) to transdermal glyceryl trinitrate (GTN) or no GTN for 7 days. The primary outcome was functional outcome (modified Rankin Scale [mRS] score) at day 90. Cognition was assessed via telephone at day 90. Stroke syndrome was classified with the Oxfordshire Community Stroke Project classification. Brain imaging was adjudicated masked to clinical information and treatment and assessed SVD (leukoaraiosis, old lacunar infarcts/lacunes, atrophy) and brain frailty (leukoaraiosis, atrophy, old vascular lesions/infarcts). Analyses used ordinal logistic regression adjusted for prognostic variables. RESULTS: In all participants and those with lacunar syndrome (LACS; 1,397, 34.8%), baseline CT imaging features of SVD and brain frailty were common and independently associated with unfavorable shifts in mRS score at day 90 (all participants: SVD score odds ratio [OR] 1.15, 95% confidence interval [CI] 1.07-1.24; brain frailty score OR 1.25, 95% CI 1.17-1.34; those with LACS: SVD score OR 1.30, 95% CI 1.15-1.47, brain frailty score OR 1.28, 95% CI 1.14-1.44). Brain frailty was associated with worse cognitive scores at 90 days in all participants and in those with LACS. CONCLUSIONS: Baseline imaging features of SVD and brain frailty were common in lacunar stroke and all stroke, predicted worse prognosis after all acute stroke with a stronger effect in lacunar stroke, and may aid future clinical decision-making. IDENTIFIER: ISRCTN99414122.

Noncontrast Computed Tomography Signs as Predictors of Hematoma Expansion, Clinical Outcome, and Response to Tranexamic Acid in Acute Intracerebral Hemorrhage.

Background and Purpose- Blend, black hole, island signs, and hypodensities are reported to predict hematoma expansion in acute intracerebral hemorrhage. We explored the value of these noncontrast computed tomography signs in predicting hematoma expansion and functional outcome in our cohort of intracerebral hemorrhage. Methods- The TICH-2 (Tranexamic acid for IntraCerebral Hemorrhage-2) was a prospective randomized controlled trial exploring the efficacy and safety of tranexamic acid in acute intracerebral hemorrhage. Baseline and 24-hour computed tomography scans of trial participants were analyzed. Hematoma expansion was defined as an increase in hematoma volume of >33% or >6 mL on 24-hour computed tomography. Poor functional outcome was defined as modified Rankin Scale of 4 to 6 at day 90. Multivariable logistic regression was performed to identify predictors of hematoma expansion and poor functional outcome. Results- Of 2325 patients recruited, 2077 (89.3%) had valid baseline and 24-hour scans. Five hundred seventy patients (27.4%) had hematoma expansion while 1259 patients (54.6%) had poor functional outcome. The prevalence of noncontrast computed tomography signs was blend sign, 366 (16.1%); black hole sign, 414 (18.2%); island sign, 200 (8.8%); and hypodensities, 701 (30.2%). Blend sign (adjusted odds ratio [aOR] 1.53 [95% CI, 1.16-2.03]; P=0.003), black hole (aOR, 2.03 [1.34-3.08]; P=0.001), and hypodensities (aOR, 2.06 [1.48-2.89]; P<0.001) were independent predictors of hematoma expansion on multivariable analysis with adjustment for covariates. Black hole sign (aOR, 1.52 [1.10-2.11]; P=0.012), hypodensities (aOR, 1.37 [1.05-1.78]; P=0.019), and island sign (aOR, 2.59 [1.21-5.55]; P=0.014) were significant predictors of poor functional outcome. Tranexamic acid reduced the risk of hematoma expansion (aOR, 0.77 [0.63-0.94]; P=0.010), but there was no significant interaction between the presence of noncontrast computed tomography signs and benefit of tranexamic acid on hematoma expansion and functional outcome (P interaction all >0.05). Conclusions- Blend sign, black hole sign, and hypodensities predict hematoma expansion while black hole sign, hypodensities, and island signs predict poor functional outcome. Noncontrast computed tomography signs did not predict a better response to tranexamic acid. Clinical Trial Registration- URL: https://www.isrctn.com. Unique identifier: ISRCTN93732214.

Continuing versus Stopping Prestroke Antihypertensive Therapy in Acute Intracerebral Hemorrhage: A Subgroup Analysis of the Efficacy of Nitric Oxide in Stroke Trial.

BACKGROUND AND PURPOSE: More than 50% of patients with acute intracerebral hemorrhage (ICH) are taking antihypertensive drugs before ictus. Although antihypertensive therapy should be given long term for secondary prevention, whether to continue or stop such treatment during the acute phase of ICH remains unclear, a question that was addressed in the Efficacy of Nitric Oxide in Stroke (ENOS) trial. METHODS: ENOS was an international multicenter, prospective, randomized, blinded endpoint trial. Among 629 patients with ICH and systolic blood pressure between 140 and 220 mmHg, 246 patients who were taking antihypertensive drugs were assigned to continue (n = 119) or to stop (n = 127) taking drugs temporarily for 7 days. The primary outcome was the modified Rankin Score at 90 days. Secondary outcomes included death, length of stay in hospital, discharge destination, activities of daily living, mood, cognition, and quality of life. RESULTS: Blood pressure level (baseline 171/92 mmHg) fell in both groups but was significantly lower at 7 days in those patients assigned to continue antihypertensive drugs (difference 9.4/3.5 mmHg, P < .01). At 90 days, the primary outcome did not differ between the groups; the adjusted common odds ratio (OR) for worse outcome with continue versus stop drugs was .92 (95% confidence interval, .45-1.89; P = .83). There was no difference between the treatment groups for any secondary outcome measure, or rates of death or serious adverse events. CONCLUSIONS: Among patients with acute ICH, immediate continuation of antihypertensive drugs during the first week did not reduce death or major disability in comparison to stopping treatment temporarily.

Glyceryl Trinitrate for Acute Intracerebral Hemorrhage: Results From the Efficacy of Nitric Oxide in Stroke (ENOS) Trial, a Subgroup Analysis.

BACKGROUND AND PURPOSE: The Efficacy of Nitric Oxide in Stroke (ENOS) trial found that transdermal glyceryl trinitrate (GTN, a nitric oxide donor) lowered blood pressure but did not improve functional outcome in patients with acute stroke. However, GTN was associated with improved outcome if patients were randomized within 6 hours of stroke onset. METHODS: In this prespecified subgroup analysis, the effect of GTN (5 mg/d for 7 days) versus no GTN was studied in 629 patients with intracerebral hemorrhage presenting within 48 hours and with systolic blood pressure ≥140 mm Hg. The primary outcome was the modified Rankin Scale at 90 days. RESULTS: Mean blood pressure at baseline was 172/93 mm Hg and significantly lower (difference -7.5/-4.2 mm Hg; both P≤0.05) on day 1 in 310 patients allocated to GTN when compared with 319 randomized to no GTN. No difference in the modified Rankin Scale was observed between those receiving GTN versus no GTN (adjusted odds ratio for worse outcome with GTN, 1.04; 95% confidence interval, 0.78-1.37; P=0.84). In the subgroup of 61 patients randomized within 6 hours, GTN improved functional outcome with a shift in the modified Rankin Scale (odds ratio, 0.22; 95% confidence interval, 0.07-0.69; P=0.001). There was no significant difference in the rates of serious adverse events between GTN and no GTN. CONCLUSIONS: In patients with intracerebral hemorrhage within 48 hours of onset, GTN lowered blood pressure was safe but did not improve functional outcome. Very early treatment might be beneficial but needs assessment in further studies. CLINICAL TRIAL REGISTRATION: URL: http://www.isrctn.com/ISRCTN99414122. Unique identifier: 99414122.

Performance characteristics of methods for quantifying spontaneous intracerebral haemorrhage: data from the Efficacy of Nitric Oxide in Stroke (ENOS) trial.

BACKGROUND: Poor prognosis after intracerebral haemorrhage (ICH) is related to haemorrhage characteristics. Along with developing therapeutic interventions, we sought to understand the performance of haemorrhage descriptors in large clinical trials. METHODS: Clinical and neuroimaging data were obtained for 548 participants with ICH from the Efficacy of Nitric Oxide in Stroke (ENOS) trial. Independent observers performed visual categorisation of the largest diameter, measured volume using ABC/2, modified ABC/2, semiautomated segmentation (SAS), fully automatic measurement methods; shape, density and intraventricular haemorrhage were also assessed. Intraobserver and interobserver reliability were determined for these measures. RESULTS: ICH volume was significantly different among standard ABC/2, modified ABC/2 and SAS: (mean) 12.8 (SD 16.3), 8.9 (9.2), 12.8 (13.1) cm(3), respectively (p<0.0001). There was excellent agreement for haemorrhage volume (n=193): ABC/2 intraobserver intraclass correlation coefficient (ICC) 0.96-0.97, interobserver ICC 0.88; modified ABC/2 intraobserver ICC 0.95-0.97, interobserver ICC 0.91; SAS intraobserver ICC 0.95-0.99, interobserver ICC 0.93; largest diameter: (visual) interadjudicator ICC 0.82, (visual vs measured) adjudicator vs observer ICC 0.71; shape intraobserver ICC 0.88 interobserver ICC 0.75; density intraobserver ICC 0.86, interobserver ICC 0.73. Graeb score (mean 3.53) and modified Graeb (5.22) scores were highly correlated. Using modified ABC/2, ICH volume was underestimated in regular (by 2.2-2.5 cm(3), p<0.0001) and irregular-shaped haemorrhages (by 4.8-4.9 cm(3), p<0.0001). Fully automated measurement of haemorrhage volume was possible in only 5% of cases. CONCLUSIONS: Formal measurement of haemorrhage characteristics and visual estimates are reproducible. The standard ABC/2 method is superior to the modified ABC/2 method for quantifying ICH volume. CLINICAL TRIAL REGISTRATION: ISRCTN9941422.

Posterior ponticles and rotational stenosis of vertebral arteries. A pilot study using Doppler ultrasound velocimetry and magnetic resonance angiography.

OBJECTIVE: To determine whether the presence of posterior ponticles markedly increases by 30% or more, the incidence of major rotational stenosis of vertebral arteries. METHODS: Doppler ultrasound studies were performed in 3 private chiropractic clinics and in the radiology department of a public hospital, and magnetic resonance angiography (MRA) studies were made in the latter location. Thirty-two chiropractic patients had Doppler velocimetery, and 16 of these patients had MRA scanning. The outcome measures included changes in Doppler velocimetry signals and MRA images indicative of marked rotational stenosis of vertebral arteries. RESULTS: All vertebral arteries from the 32 patients displayed no signs indicative of marked rotational stenosis. CONCLUSION: The findings of this study show that the incidence of major rotational stenosis of vertebral arteries is not markedly increased by the presence of posterior ponticles.

Vertebral arteries and cervical rotation: modeling and magnetic resonance angiography studies.

OBJECTIVE: To determine whether lumen narrowing in vertebral arteries during atlanto-axial rotation is due to stretch or localized compression. DESIGN AND SETTING: Experiments with models were made in a private chiropractic clinic, whereas studies of cadaveric specimens were performed in an anatomy laboratory. Doppler ultrasound and magnetic resonance angiography (MRA) studies were carried out in the radiology department of a public hospital. PATIENTS: Eight patients had their vertebral arteries examined by use of a Doppler velocimeter and MRA. MAIN OUTCOME MEASURE: Stenosis of the vertebral arteries caused by stretch, localized compression, or kinking. RESULTS: All 16 vertebral arteries from the 8 patients displayed no changes in their lumen dimensions with full cervical rotation, although curves in each of the arteries did change. The model and cadaveric vertebral arteries demonstrated localized compression or kinking of the vessel wall with atlanto-axial rotation contralaterally but revealed no evidence of major contribution of stretching to stenosis. CONCLUSION: The lumen of vertebral arteries is usually unaffected by atlanto-axial rotation. In cases where there is stenosis, this is mainly due to localized compression or kinking. These findings are relevant to premanipulative screening of vertebral arteries with Doppler ultrasound scanning.