Jesus Juega

Admission CT perfusion may overestimate initial infarct core: the ghost infarct core concept.

Background Identifying infarct core on admission is essential to establish the amount of salvageable tissue and indicate reperfusion therapies. Infarct core is established on CT perfusion (CTP) as the severely hypoperfused area, however the correlation between hypoperfusion and infarct core may be time-dependent as it is not a direct indicator of tissue damage. This study aims to characterize those cases in which the admission core lesion on CTP does not reflect an infarct on follow-up imaging. Methods We studied patients with cerebral large vessel occlusion who underwent CTP on admission but received endovascular thrombectomy based on a non-contrast CT Alberta Stroke Program Early CT Score (ASPECTS) >6. Admission infarct core was measured on initial cerebral blood volume (CBV) CTP and final infarct on follow-up CT. We defined ghost infarct core (GIC) as initial core minus final infarct >10 mL. Results 79 patients were studied. Median National Institutes of Health Stroke Scale (NIHSS) score was 17 (11–20), median time from symptoms to CTP was 215 (87–327) min, and recanalization rate (TICI 2b–3) was 77%. Thirty patients (38%) presented with a GIC >10 mL. GIC >10 mL was associated with recanalization (TICI 2b–3: 90% vs 68%; p=0.026), admission glycemia (<185 mg/dL: 42% vs 0%; p=0.028), and time to CTP (<185 min: 51% vs >185 min: 26%; p=0.033). An adjusted logistic regression model identified time from symptom to CTP imaging <185 min as the only predictor of GIC >10 mL (OR 2.89, 95% CI 1.04 to 8.09). At 24 hours, clinical improvement was more frequent in patients with GIC >10 mL (66.6% vs 39%; p=0.017). Conclusions CT perfusion may overestimate final infarct core, especially in the early time window. Selecting patients for reperfusion therapies based on the CTP mismatch concept may deny treatment to patients who might still benefit from reperfusion.

Improving the Evaluation of Collateral Circulation by Multiphase Computed Tomography Angiography in Acute Stroke Patients Treated with Endovascular Reperfusion Therapies.

Good collateral circulation (CC) is associated with favorable outcomes in acute stroke, but the best technique to evaluate collaterals is controversial. Single-phase computed tomography angiography (sCTA) is widely used but lacks temporal resolution. We aim to compare CC evaluation by sCTA and multiphase CTA (mCTA) as predictors of outcome in endovascular treated patients. Methods: Consecutive endovascular treated patients with M1 middle cerebral artery (MCA) or terminal intracranial carotid artery (TICA) occlusion confirmed by sCTA were included. Two more CTA acquisitions with 8- and 16-second delays were performed for mCTA. Endovascular thrombectomy was performed independently of the CC status according to a local protocol [Alberta Stroke Program Early CT score (ASPECTS) >6, modified Rankin scale (mRS) score <3]. CC on sCTA and mCTA were compared. Results: 108 patients were included. Their mean age was 69.6 ± 13 years and their median National Institutes of Health Stroke Scale (NIHSS) score was 17 (interquartile range 8). 79 (73.1%) had M1 MCA and 29 (26.9%) TICA occlusions. The mean time from symptom onset to CTA was 146.8 ± 96.5 min. On sCTA, 50.9% patients presented good CC vs. 57.5% on mCTA. Good CC status in both sCTA and mCTA had a lower 24-hour infarct volume (27.4 vs. 74.8 cm3 on sCTA, p = 0.04; 17.2 vs. 97.8 cm3 on mCTA, p < 0.01). However, only good CC on mCTA was associated with lower 24-hour (5 vs. 8.5, p = 0.04) and median discharge NIHSS (2 vs. 4.5, p = 0.04) scores and functional independency (mRS score <3) at 3 months (76.9 vs. 23.1%, p < 0.01). In a logistic regression model including age, NIHSS, ASPECTS and recanalization, only age (OR 0.96, 95% CI 0.93-0.99, p = 0.02) and good CC on mCTA (OR 5, 95% CI 1.99-12.6, p < 0.01) were independent predictors of functional outcome at 3 months. Conclusion: CC evaluation by mCTA is a better prognostic marker than CC evaluation by sCTA for clinical and functional endpoints in acute stroke patients treated with endovascular thrombectomy.

Direct transfer to angiosuite to reduce door-to-puncture time in thrombectomy for acute stroke

Objective To evaluate direct transfer to the angiosuite protocol of patients with acute stroke, candidates for endovascular treatment (EVT). Methods We studied workflow metrics of all patients with stroke who had undergone EVT in the past 12 months. Patients followed three protocols: direct transfer to emergency room (DTER), CT room (DTCT) or angiosuite (DTAS, only last 6 months if admission National Institute of Health Stroke Scale (NIHSS) score >9 and time from onset <4.5 hours) according to staff/suite availability. DTAS patients underwent cone-beam CT before femoral puncture. Dramatic clinical improvement was defined as 10 NIHSS points drop at 24 hours. Results 201 patients were included: 87 DTER (43.3%), 74 DTCT (36.8%), 40 DTAS (19.9%). Ten DTAS patients (25%) did not receive EVT: 3 (7.5%) showed intracranial hemorrhage on cone-beam CT and 7 (17.5%) did not show an occlusion on angiography. Mean door-to-puncture (D2P) time was shorter in DTAS (17±8 min) than DTCT (60±29 min; p<0.01). D2P was longer in DTER (90±53 min) than in the other protocols (p<0.01). For outcome analyses only patients who received EVT were compared; no significant differences in baseline characteristics, including time from symptom-onset to admission, puncture-to-recanalization, or recanalization rate, were seen. However, time from symptom-to-puncture (DTAS: 197±72 min, DTER: 279±156, DTCT: 224±142 min; p=0.01) and symptom-to-recanalization (DTAS: 257±74, DTER: 355±158, DTCT: 279±146 min; p<0.01) were longer in the DTER group. At 24 hours, there were no differences in NIHSS score (p=0.81); however, the rate of dramatic clinical improvement was significantly higher in DTAS: 48.6% (DTER 24.1%, DTCT 27.4%); p=0.01). An adjusted model pointed to shorter onset-to-puncture time as an independent predictor of dramatic improvement (OR=1.23, 95% CI 1.13 to 133; p<0.01) Conclusion In a subgroup of patients direct transfer and triage in the angiosuite seems feasible, safe, and achieves significant reduction in hospital workflow times.

Multiphase CT Angiography Improves Prediction of Intracerebral Hemorrhage Expansion

Purpose To determine the prevalence of the spot sign and the accuracy of using the spot sign to predict intracerebral hemorrhage (ICH) expansion with standardized multiphase computed tomographic (CT) angiography. Materials and Methods This prospective observational cohort study included 123 consecutive patients with acute ICH (onset <6 hours). Patients underwent multiphase CT angiography in three automated phases after injection of contrast material. Patients were classified as having one of four patterns (pattern A, B, C, or D) according to the presence of the spot sign in the three phases. Pattern A was the more arterial pattern, and pattern D was the more venous pattern. Ninety-five patients underwent follow-up unenhanced CT 24 hours after symptom onset. Primary outcome was substantial hematoma expansion (>33% or >6 mL) at 24 hours. Associations between the presence of the spot sign and substantial hematoma expansion were assessed by using the Pearson χ2 test. Results The later the phase of CT angiography, the higher the frequency of the spot sign. The spot sign was seen in 29.3% of patients in phase 1, 43.1% of patients in phase 2, and 46.3% of patients in phase 3 (P < .001). The presence of the spot sign in any phase was related to substantial hematoma expansion (P < .001 for all comparisons; Bonferroni adjusted α = .0125), with highest positive predictive value in phase 1 (64.0%) and highest negative predictive value in phase 2 (90.2%). The more arterial the pattern of spot sign presentation, the greater the frequency of substantial hematoma expansion (P = .013). Absolute hematoma growth analysis revealed a hierarchical pattern of spot sign presentations, as follows: A > B > C > D > no spot sign (P = .002). Conclusion Multiphase CT angiography can help differentiate among different forms of spot sign presentation and can help stratify patients at risk for hematoma expansion. The more arterial the spot sign pattern, the greater the frequency and extent of expansion.

CBV_ASPECTS Improvement over CT_ASPECTS on Determining Irreversible Ischemic Lesion Decreases over Time

The Alberta Stroke Program Early CT Score (ASPECTS) is a useful scoring system for assessing early ischemic signs on noncontrast computed tomography (CT). Cerebral blood volume (CBV) on CT perfusion defines the core lesion assumed to be irreversibly damaged. We aim to explore the advantages of CBV_ASPECTS over CT_ASPECTS in the prediction of final infarct volume according to time. Methods: Consecutive patients with anterior circulation stroke who underwent endovascular reperfusion according to initial CT_ASPECTS ≥7 were studied. CBV_ASPECTS was assessed blindly later on. Recanalization was defined as thrombolysis in cerebral ischemia score 2b-3. Final infarct volumes were measured on follow-up imaging. We compared ASPECTS on CBV and CT images, and defined ASPECTS agreement as: CT_ASPECTS - CBV_ASPECTS ≤1. Results: Sixty-five patients, with a mean age of 67 ± 14 years and a median National Institutes of Health Stroke Scale score of 16 (range 10-20), were studied. The recanalization rate was 78.5%. The median CT_ASPECTS was 9 (range 8-10), and the CBV_ASPECTS was 8 (range 8-10). The mean time from symptoms to CT was 219 ± 143 min. Fifty patients (76.9%) showed ASPECTS agreement. The ASPECTS difference was inversely correlated to the time from symptoms to CT (r = -0.36, p < 0.01). A ROC curve defined 120 min as the best cutoff point after which the ASPECTS difference becomes more frequently ≤1. After 120 min, 89.5% of the patients showed ASPECTS agreement (as compared with 37.5% for <120 min, p < 0.01). CBV_ASPECTS but not CT_ASPECTS correlated with final infarct (r = -0.33, p < 0.01). However, if CT was done >2 h after symptom onset, CT_ASPECTS also correlated to final infarct (r = -0.39, p = 0.01). Conclusions: In acute stroke, CBV_ASPECTS correlates with the final infarct volume. However, when CT is performed after 120 min from symptom onset, CBV_ASPECTS does not add relevant information to CT_ASPECTS.

Abstract TP358: Stroke Nurse Activation Improves Time Metrics For Reperfusion In Acute Stroke Treatment

Background and aim: Shortening door-to-needle(DTN) and door-to-groin (DTG) times without compromising safety, is one of the major goals of reperfusion therapy. A pre-hospital Stroke Code(SC) activa...

Ghost Infarct Core and Admission Computed Tomography Perfusion: Redefining the Role of Neuroimaging in Acute Ischemic Stroke

Background: Determining the size of infarct extent is crucial to elect patients for reperfusion therapies. Computed tomography perfusion (CTP) based on cerebral blood volume may overestimate infarct core on admission and consequently include ghost infarct core (GIC) in a definitive lesional area. Purpose: Our goal was to confirm and better characterize the GIC phenomenon using CTP cerebral blood flow (CBF) as the reference parameter to determine infarct core. Methods: We performed a retrospective, single-center analysis of consecutive thrombectomies of middle cerebral or intracranial internal carotid artery occlusions considering noncontrast CT Alberta Stroke Program Early CT Score ≥6 in patients with pretreatment CTP. We used the RAPID® software to measure admission infarct core based on initial CBF. The final infarct was extracted from follow-up CT. GIC was defined as initial core minus final infarct > 10 mL. Results: A total of 123 patients were included. The median National Institutes of Health Stroke Scale score was 18 (13–20), the median time from symptoms to CTP was 188 (67–288) min, and the recanalization rate (Thrombolysis in Cerebral Infarction score 2b, 2c, or 3) was 83%. Twenty patients (16%) presented with GIC. GIC was associated with shorter time to recanalization (150 [105–291] vs. 255 [163–367] min, p = 0.05) and larger initial CBF core volume (38 [26–59] vs. 6 [0–27] mL, p < 0.001). An adjusted logistic regression model identified time to recanalization < 302 min (OR 4.598, 95% CI 1.143–18.495, p = 0.032) and initial infarct volume (OR 1.01, 95% CI 1.001–1.019, p = 0.032) as independent predictors of GIC. At 24 h, clinical improvement was more frequent in patients with GIC (80 vs. 49%, p = 0.01). Conclusions: CTP CBF < 30% may overestimate infarct core volume, especially in patients imaged in the very early time window and with fast complete reperfusion. Therefore, the CTP CBF technique may exclude patients who would benefit from endovascular treatment.

Yield of atrial fibrillation detection with Textile Wearable Holter from the acute phase of stroke: Pilot study of Crypto-AF registry

BACKGROUND We describe the feasibility of monitoring with a Textile Wearable Holter (TWH) in patients included in Crypto AF registry. METHODS We monitored cryptogenic stroke patients from stroke onset (<3days) continuously during 28days. We employed a TWH composed by a garment and a recorder. We compared two garments (Lead and Vest) to assess rate of undiagnosed Atrial Fibrillation (AF) detection, monitoring compliance, comfortability (1 to 5 points), skin lesions, and time analyzed. We describe the timing of AF detection in three periods (0-3, 4-15 and 16-28days). RESULTS The rate of undiagnosed AF detection with TWH was 21.9% (32 out of 146 patients who completed the monitoring). Global time compliance was 90% of the time expected (583/644h). The level of comfortability was 4 points (IQR 3-5). We detected reversible skin lesions in 5.47% (8/146). The comfortability was similar but time compliance (in hours) was longer in Vest group 591 (IQR [521-639]) vs. Lead 566 (IQR [397-620]) (p=0.025). Also, time analyzed was more prolonged in Vest group 497 (IQR [419-557]) vs. Lead (336h (IQR [140-520]) (p=0.001)). The incidence of AF increases from 5.6% (at 3days) to 17.5% (at 15th day) and up to 20.9% (at 28th day). The percentage of AF episodes detected only in each period was 12.5% (0-3days); 21.7% (4-15days) and 19% (16-28days). CONCLUSIONS 28days Holter monitoring from the acute phase of the stroke was feasible with TWH. Following our protocol, only five patients were needed to screen to detected one case of AF.

Prosthetic Valve Thrombosis in the Acute Phase of the Stroke: Relevance of Detection and Follow-Up

BACKGROUND Stroke may be the first symptom of prosthetic valve thrombosis (PVT); therefore, rapid diagnosis and therapy are crucial. We aimed to evaluate the prevalence, main predictors, and long-term clinical evolution of patients with PVT in the acute phase of stroke. METHODS We studied consecutive acute ischemic stroke patients with prosthetic heart valves who underwent emergent transesophageal echocardiography (TEE) during a 5-year period. Two groups were defined depending on the presence of PVT (PVT or non-PVT groups). Baseline characteristics, TEE findings, and international normalized ratios (INRs) at the stroke event were registered. Follow-up visits and TEE control examinations were performed. RESULTS Sixty-seven patients were registered. TEE was performed within the first week in 85% of patients (n = 57). PVT was diagnosed in 41.8% of cases (n = 28). Clinical severity and baseline INR level showed no differences when the PVT and non-PVT groups were compared. The presence of PVT was associated with the mitral valve location as compared with the aortic valve location (75% versus 25%, P = .003), the presence of spontaneous echocontrast (64.3% versus 35.9%, P = .022), and low ejection fraction (66.7% versus 32.7%, P = .019). The PVT group showed a trend toward higher percentage of recurrence (10.7% versus 2.5%, P = .102) in the follow up period (mean follow-up 25 months). CONCLUSIONS The detection of PVT in the acute stroke phase was relevant, as the stroke recurrence rate was considerable. Therefore, all patients with prosthetic heart valve should undergo emergent TEE.