Can flat-detector CT after successful endovascular treatment predict long-term outcome in patients with large vessel occlusion? An Alberta Stroke Programme Early CT Score-based study

PURPOSE

Recent studies postulate a high prognostic value of the Alberta Stroke Programme Early CT Score (ASPECTS) applied on non-contrast whole-brain flat-detector CT (FDCT) after successful endovascular treatment (EVT). The aim of this study was the evaluation of long-term patient outcome after endovascular treatment using postinterventional FDCT.

METHODS

Using a local database (Stroke Research Consortium in Northern Bavaria, STAMINA), 517 patients with successful endovascular treatment (modified Thrombolysis in Cerebral Infarction (mTICI) ≥ 2B) due to acute ischaemic stroke (AIS) and large vessel occlusion (LVO) of the anterior circulation were recruited retrospectively. In all cases, non-contrast FDCT after EVT was analysed with special focus at ASPECTS. These results were correlated with the functional outcome in long-term (modified Rankin Scale (mRS) shift from pre-stroke to 90 days after discharge).

RESULTS

A significant difference in FDCT-ASPECTS compared to the subgroup of favourable vs. unfavourable outcome (Δ mRS) (median ASPECTS 10 (10-9) vs. median ASPECTS 9 (10-7); p = 0,001) could be demonstrated. Multivariable regression analysis revealed FDCT-ASPECTS (OR 0.234, 95% CI - 0.102-0.008, p = 0.022) along with the NHISS at admission (OR 0.169, 95% CI 0.003-0.018, p = 0.008) as independent factors for a favourable outcome. Cut-off point for a favourable outcome (Δ mRS) was identified at an ASPECTS ≥ 8 (sensitivity 90.6%, specificity 35%).

CONCLUSION

For patients with LVO and successful EVT, FDCT-ASPECTS was found to be highly reliable in predicting long-term outcome.

The butterfly effect: improving brain cone-beam CT image artifacts for stroke assessment using a novel dual-axis trajectory

BACKGROUND

Cone-beam computed tomography (CBCT) imaging of the brain can be performed in the angiography suite to support various neurovascular procedures. Relying on CBCT brain imaging solely, however, still lacks full diagnostic confidence due to the inferior image quality compared with CT and various imaging artifacts that persist even with modern CBCT.

OBJECTIVE

To perform a detailed evaluation of image artifact improvement using a new CBCT protocol which implements a novel dual-axis 'butterfly' trajectory.

METHODS

Our study included 94 scans from 47 patients who received CBCT imaging for assessment of either ischemia or hemorrhage during a neurovascular procedure. Both a traditional uni-axis 'circular' and novel dual-axis 'butterfly' protocol were performed on each patient (same-patient control). Each brain scan was divided into six regions and scored out of 3 based on six artifacts originating from various physics-based and patient-based sources.

RESULTS

The dual-axis trajectory produces CBCT images with significantly fewer image artifacts than the traditional circular scan (whole brain average artifact score, AS: 0.20 vs 0.33), with the greatest improvement in bone beam hardening (AS: 0.13 vs 0.78) and cone-beam artifacts (AS: 0.04 vs 0.55).

CONCLUSIONS

Recent developments in CBCT imaging protocols have significantly improved image artifacts, which has improved diagnostic confidence for stroke and supports a direct-to-angiography suite transfer approach for patients with acute ischemic stroke.

Clinical Comparison of FD-CT and MS-CT in Aneurysmal Subarachnoid Haemorrhage: A Single Center Experience

Single-center comparison of postinterventional multislice computed tomography (MS-CT) and flat-detector computed tomography (FD-CT) in patients with subarachnoid haemorrhage (SAH) and endovascularly treated cerebral aneurysms with a focus on detection of posttherapeutical complications. Patients with endovascularly treated aneurysmal SAH undergoing both MS-CT and FD-CT within 24 h after intervention were included. Datasets were compared regarding image quality (IQ) as well as qualitative (detection of SAH, intracerebral haemorrhage [ICH], intraventricular haemorrhage [IVH], external ventricular drain [EVD] position, acute obstructive hydrocephalus [AOH]) and quantitative (cella media distance [CMD], modified Graeb score [GS]) parameters. 410 patients with endovascularly treated aneurysmal SAH were included. IQ was equal between MS-CT and FD-CT. FD-CT allowed equal detection of SAH and ICH in comparison to MS-CT. FD-CT allowed excellent detection of IVH and delineation of EVD position with strong agreement to MS-CT findings. FD-CT allowed equal detection of AOH in comparison to MS-CT. There was no significant difference of CMD and GS between FD-CT and MS-CT. Postinterventional FD-CT yields equivalent diagnostic value in patients with endovascular treated SAH as MS-CT. Enabling reliable detection of SAH-associated complications within the angiosuite, FD-CT might be an efficient and safe imaging modality in these clinical emergencies.

Advances in cerebral perfusion imaging techniques in acute ischemic stroke

The application of cerebral perfusion imaging has demonstrated significant assessment benefits and an ability to establish an appropriate triage of patients with acute ischemic stroke (AIS) and large artery occlusion (LAO) in the extended time window. Computed tomography perfusion (CTP) and magnetic resonance imaging (MRI) are routinely used to determine the ischemic core, as well as the tissue at risk, to aid in therapeutic decision-making. However, the time required to transport patients to imaging extends the door-to-reperfusion time. C-arm cone-beam CT (CBCT) is a novel tomography technology that combines 2D radiography and 3D CT imaging based on the digital subtraction angiography platform. In comparison with CT or MRI perfusion techniques, CBCT combined with catheterized angiogram or therapy can serve as a "one-stop-shop" for the diagnosis and treatment of AIS, and greatly reduce the door to reperfusion time. Here, we review the current evidence on the efficacy and theoretical basis of CBCT, as well as other perfusion techniques, with the purpose to assist clinicians to establish an effective and repaid workflow for patients with AIS and LAO in clinical practice.

Reference-free learning-based similarity metric for motion compensation in cone-beam CT

Purpose. Patient motion artifacts present a prevalent challenge to image quality in interventional cone-beam CT (CBCT). We propose a novel reference-free similarity metric (DL-VIF) that leverages the capability of deep convolutional neural networks (CNN) to learn features associated with motion artifacts within realistic anatomical features. DL-VIF aims to address shortcomings of conventional metrics of motion-induced image quality degradation that favor characteristics associated with motion-free images, such as sharpness or piecewise constancy, but lack any awareness of the underlying anatomy, potentially promoting images depicting unrealistic image content. DL-VIF was integrated in an autofocus motion compensation framework to test its performance for motion estimation in interventional CBCT.Methods. DL-VIF is a reference-free surrogate for the previously reported visual image fidelity (VIF) metric, computed against a motion-free reference, generated using a CNN trained using simulated motion-corrupted and motion-free CBCT data. Relatively shallow (2-ResBlock) and deep (3-Resblock) CNN architectures were trained and tested to assess sensitivity to motion artifacts and generalizability to unseen anatomy and motion patterns. DL-VIF was integrated into an autofocus framework for rigid motion compensation in head/brain CBCT and assessed in simulation and cadaver studies in comparison to a conventional gradient entropy metric.Results. The 2-ResBlock architecture better reflected motion severity and extrapolated to unseen data, whereas 3-ResBlock was found more susceptible to overfitting, limiting its generalizability to unseen scenarios. DL-VIF outperformed gradient entropy in simulation studies yielding average multi-resolution structural similarity index (SSIM) improvement over uncompensated image of 0.068 and 0.034, respectively, referenced to motion-free images. DL-VIF was also more robust in motion compensation, evidenced by reduced variance in SSIM for various motion patterns (σ_DL-VIF = 0.008 versusσ_{gradient entropy} = 0.019). Similarly, in cadaver studies, DL-VIF demonstrated superior motion compensation compared to gradient entropy (an average SSIM improvement of 0.043 (5%) versus little improvement and even degradation in SSIM, respectively) and visually improved image quality even in severely motion-corrupted images.Conclusion: The studies demonstrated the feasibility of building reference-free similarity metrics for quantification of motion-induced image quality degradation and distortion of anatomical structures in CBCT. DL-VIF provides a reliable surrogate for motion severity, penalizes unrealistic distortions, and presents a valuable new objective function for autofocus motion compensation in CBCT.

Novel flat-panel cone-beam CT compared to multi-detector CT for assessment of acute ischemic stroke: A prospective study

PURPOSE

Cone beam CT (CBCT) imaging assessment of acute ischemic stroke (AIS) patients with large-vessel occlusion (LVO) in the angiosuite may improve stroke workflow and decrease time to recanalization. In order for this workflow to gain widespread acceptance, current CBCT imaging needs further development to improve image quality. Our study aimed to compare the image quality of a new CBCT protocol performed directly in the angiosuite with imaging from multidetector CT as a gold standard.

METHODS

AIS patients with an LVO who were candidates for endovascular treatment were prospectively included in this study. Following conventional multidetector CT (MDCT), patients underwent unenhanced cone beam CT (XperCT, Philips) imaging in the angiosuite, using two different protocols: a standard 20.8 s XperCT and/or an improved 10.4 s XperCT protocol. Images were evaluated using both qualitative and quantitative methods.

RESULTS

We included 65 patients in the study. Patients received CBCT imaging prior to endovascular treatment; 18 patients were assessed with a standard 20.8 s protocol scans and 47 with a newer 10.4 s scan. The quantitative analysis showed that the mean contrast-to-noise ratio (CNR) was significantly higher for the newer 10.4 s protocol compared with the 20.8 s protocol (2.08 +/- 0.64 vs. 1.15 +/- 0.27, p < 0.004) and the mean image noise was significantly lower for the 10.4 s XperCTs when compared with the 20.8 s XperCTs (6.30 +/- 1.34 vs. 7.82 +/- 2.03, p=<0.003). Qualitative analysis, including 6 measures of image quality, demonstrated that 74.1 % of the 10.4 s XperCT scans were ranked as 'Acceptable' for assessing parenchymal imaging in AIS patients(scoring 3-5 points on a 5-point Likert-scale), compared with 32.4 % of the standard 20.8 s XperCT and 100 % of the MDCT scans. Compared to the MDCT studies, 83 % of the 10.4 s XperCT scans were deemed sufficient image quality for a direct-to-angiosuite selection, compared to only 11 % for the standard 20.8 s scans. The largest image quality improvements included grey/white matter differentiation (59 % improvement), and reduction of image noise and artefacts (63 % & 50 % improvement, respectively).

CONCLUSIONS

Continued advances in cone-beam CT allow marked improvements in image quality for the assessment of brain parenchyma, which supports a direct-to-angiosuite approach for AIS patients eligible for thrombectomy treatment.

Radioprotection of eye lens using protective material in neuro cone-beam computed tomography: Estimation of dose reduction rate and image quality

PURPOSE

In cerebral angiography, for diagnosis and interventional neuroradiology, cone-beam computed tomography (CBCT) scan is frequently performed for evaluating brain parenchyma, cerebral hemorrhage, and cerebral infarction. However, the patient's eye lens is more frequently exposed to excessive doses in these scans than in the previous angiography and interventional neuroradiology (INR) procedures. Hence, radioprotection for the lenses is needed. This study selects the most suitable eye lens protection material for CBCT from among nine materials by evaluating the dose reduction rate and image quality.

METHODS

To determine the dose reduction rate, the lens doses were measured using an anthropomorphic head phantom and a real-time dosimeter. For image quality assessment, the artifact index was calculated based on the pixel value and image noise within various regions of interest in a water phantom.

RESULTS

The protective materials exhibited dose reduction; however, streak artifacts were observed near the materials. The dose reduction rate and the degree of the artifact varied significantly depending on the protective material. The dose reduction rates were 14.6%, 14.2%, and 26.0% when bismuth shield: normal (bismuth shield in the shape of an eye mask), bismuth shield: separate (two separate bismuth shields), and lead goggles were used, respectively. The "separate" bismuth shield was found to be effective in dose reduction without lowering the image quality.

CONCLUSION

We found that bismuth shields and lead goggles are suitable protective devices for the optimal reduction of lens doses.

C-arm CT imaging with the extended line-ellipse-line trajectory: first implementation on a state-of-the-art robotic angiography system

Three-dimensional cone-beam imaging has become valuable in interventional radiology. Currently, this tool, referred to as C-arm CT, employs a circular short-scan for data acquisition, which limits the axial volume coverage and yields unavoidable cone-beam artifacts. To improve flexibility in axial coverage and image quality, there is a critical need for novel data acquisition geometries and related image reconstruction algorithms. For this purpose, we previously introduced the extended line-ellipse-line trajectory, which allows complete scanning of arbitrary volume lengths in the axial direction together with adjustable axial beam collimation, from narrow to wide depending on the targeted application. A first implementation of this trajectory on a state-of-the-art robotic angiography system is reported here. More specifically, an assessment of the quality of this first implementation is presented. The assessment is in terms of geometric fidelity and repeatability, complemented with a first visual inspection of how well the implementation enables imaging an anthropomorphic head phantom. The geometric fidelity analysis shows that the ideal trajectory is closely emulated, with only minor deviations that have no impact on data completeness and clinical practicality. Also, mean backprojection errors over short-term repetitions are shown to be below the detector pixel size at field-of-view center for most views, which indicates repeatability is satisfactory for clinical utilization. These repeatability observations are further supported by values of the Structural Similarity Index Metric above 94% for reconstructions of the FORBILD head phantom from computer-simulated data based on repeated data acquisition geometries. Last, the real data experiment with the anthropomorphic head phantom shows that the high contrast features of the phantom are well reconstructed without distortions as well as without breaks or other disturbing transition zones, which was not obvious given the complexity of the data acquisition geometry and the major variations in axial coverage that occur over the scan.

Flat-panel detector CT assessment in stroke to reduce times to intra-arterial treatment: A study of multiphase computed tomography angiography in the angiography suite to bypass conventional imaging

BACKGROUND

Bypassing the emergency department and the computed tomography suite by directly transporting to the neuroangiography suite for imaging assessment and treatment may shorten reperfusion times while maintaining proper patient selection.

OBJECTIVE

To determine whether flat-panel detector multiphase computed tomography angiography protocol is associated with reduced treatment times and a similar safety profile as the standard imaging protocol.

METHODS

Single-center prospective study of consecutive patients with anterior circulation large vessel occlusion strokes transferred to our facility for consideration of endovascular therapy from May 2016 to December 2017. Those with basilar strokes and/or presenting to the emergency department were excluded. Patients were categorized into two groups: (1) flat-panel detector CT assessment in stroke to reduce times to intra-arterial treatment group, with patients transferred directly to the suite for multiphase computed tomography angiography; and (2) patients undergoing standard protocol including computed tomography ± computed tomography angiography/CT perfusion. The groups were matched for age, baseline National Institute of Health Stroke Scale, and pretreatment glucose. Baseline characteristics, time metrics, and outcomes were compared.

RESULTS

Out of 419 patients who underwent endovascular therapy over the study period, 210 patients fit inclusion criteria, with 54 (25.7%) in the flat-panel detector CT assessment in stroke to reduce times to intra-arterial treatment group. After matching, 49 flat-panel detector CT assessment in stroke to reduce times to intra-arterial treatment/control pairs were generated and analyzed. Baseline characteristics were well balanced. Flat-panel detector CT assessment in stroke to reduce times to intra-arterial treatment patients had significantly shorter median door-to-puncture (33 [26.5-47] vs. 55 [44.5-66] min, p < 0.001), door-to-reperfusion (85 [57.5-115.5] vs. 110 [80-153], p = 0.005) and picture-to-puncture (18 [13.5-22.5] vs. 42 [32-47.5] min, p < 0.001) times. There were no differences in rates of successful reperfusion (modified thrombolysis in cerebral infarction 2b-3, 95.9% vs. 100%, p = 0.5), parenchymal hematomas type-2 (4.1% vs. 2%, p = 1.00), good outcome (90-day modified Rankin Scale 0-2, 44.9% vs. 40.8%, p = 0.68), and 90-day mortality (14.3% vs. 22.4%, p = 0.30).

CONCLUSION

Directly transferring patients to angiography and using multiphase computed tomography angiography to determine the eligibility for endovascular therapy is safe and may result in a significant reduction in treatment times. Future larger studies are warranted.

Utility of Immediate Postprocedural Cone Beam Computed Tomography Scan in the Detection of Ischemic and Hemorrhagic Complications in Pediatric Neurointerventional Surgery

BACKGROUND

Cone beam computed tomography (CBCT) imaging is used commonly in neurointerventional surgery for rapid intraprocedural assessment and planning of intracranial interventions. Our goal was to evaluate the ability of immediate postprocedural CBCT scan in assessing potential complications in pediatric patients.

METHODS

A retrospective review was completed to include all pediatric patients at our hospital with an immediate postprocedural CBCT scan with the Artis Q system. Demographic, clinical, and imaging data were examined. CBCT images were reviewed by 3 independent neurointerventionalists to assess ventricular system/subarachnoid spaces, gray-white differentiation, and ischemia or hemorrhage if present. Each assessment was rated qualitatively on a 4-point scale and was compared with conventional computed tomography (cCT) scan when available. Interrater reliability was assessed and radiation dose data were reviewed.

RESULTS

Thirty-five patients were included with an average age of 11.0 ± 5.1 years (median, 10.9; range, 1.1-18 years). Of the patients, 54.3% were boys; 34.3% were Hispanic and 34.3% were non-Hispanic white. Diagnoses included a variety of vascular pathologies. CBCT scan had a mean score of 2.69 ± 0.54 out of 3 for ventricular and subarachnoid space assessment with a combined interrater reliability of 0.82, 1.71 ± 1.38 for hemorrhage with a combined interrater reliability of 1.00, and 0.52 ± 0.60 for gray-white differentiation with a combined interrater reliability of 0.79.

CONCLUSIONS

Immediate postprocedural CBCT images were adequate to detect ventricular size/subarachnoid spaces changes and large volume hemorrhage compared with cCT scan in pediatric patients. However, there are limitations using immediate CBCT images to detect small volume hemorrhage and ischemic changes.

Diagnosing Early Ischemic Changes with the Latest-Generation Flat Detector CT: A Comparative Study with Multidetector CT

BACKGROUND AND PURPOSE

One-stop management of mechanical thrombectomy-eligible patients with large-vessel occlusion represents an innovative approach in acute stroke treatment. This approach reduces door-to-reperfusion times by omitting multidetector CT, using flat detector CT as pre-mechanical thrombectomy imaging. The purpose of this study was to compare the diagnostic performance of the latest-generation flat detector CT with multidetector CT.

MATERIALS AND METHODS

Prospectively derived data from patients with ischemic stroke with large-vessel occlusion and mechanical thrombectomy were analyzed in this monocentric study. All included patients underwent multidetector CT before referral to our comprehensive stroke center and flat detector CT in the angiography suite before mechanical thrombectomy. Diagnosis of early ischemic signs, quantified by the ASPECTS, was compared between modalities using cross tables, the Pearson correlation, and Bland-Altman plots. The predictive value of multidetector CT- and flat detector CT-derived ASPECTS for functional outcome was investigated using area under the receiver operating characteristic curve analysis.

RESULTS

Of 25 patients, 24 (96%) had flat detector CT with sufficient diagnostic quality. Median multidetector CT and flat detector CT ASPECTSs were 7 (interquartile range, 5.5-9 and 4.25-8, respectively) with a mean period of 143.6 ± 49.5 minutes between both modalities. The overall sensitivity was 85.1% and specificity was 83.1% for flat detector CT ASPECTS compared with multidetector CT ASPECTS as the reference technique. Multidetector CT and flat detector CT ASPECTS were strongly correlated (r = 0.849, P < .001) and moderately predicted functional outcome (area under the receiver operating characteristic curve, 0.738; P = .007 and .715; P = .069, respectively).

CONCLUSIONS

Determination of ASPECTS on flat detector CT is feasible, showing no significant difference compared with multidetector CT ASPECTS and a similar predictive value for functional outcome. Our findings support the use of flat detector CT for emergency stroke imaging before mechanical thrombectomy to reduce door-to-groin time.

Optimized Management of Endovascular Treatment for Acute Ischemic Stroke

This manuscript describes a streamlined protocol for the management of patients with acute ischemic stroke, which aims at the minimization of time from hospital admission to reperfusion. Rapid restoration of cerebral blood flow is essential for the outcomes of patients with acute ischemic stroke. Endovascular treatment (EVT) has become the standard of care to accomplish this in patients with acute stroke due to large vessel occlusion (LVO). To achieve reperfusion of ischemic brain regions as fast as possible, all in-hospital time delays have to be carefully avoided. Therefore, management of patients with acute ischemic stroke was optimized with an interdisciplinary standard operating procedure (SOP). Stroke neurologists, diagnostic as well as interventional neuroradiologists, and anesthesiologists streamlined all necessary processes from patient admission and diagnosis to EVT of eligible patients. Target times for every step were established. Actually achieved times were prospectively recorded along with clinical data and imaging scores for all endovascularly treated stroke patients. These data were regularly analyzed and discussed in interdisciplinary team meetings. Potential issues were evaluated and all staff involved was trained to adhere to the SOP. This streamlined patient management approach and enhanced interdisciplinary collaboration reduced time from patient admission to reperfusion significantly and was accompanied by a beneficial effect on clinical outcomes.

Interfacility Transfer Directly to the Neuroangiography Suite in Acute Ischemic Stroke Patients Undergoing Thrombectomy

BACKGROUND AND PURPOSE

In patients identified at referring facilities with acute ischemic stroke caused by a large vessel occlusion, bypassing the emergency department (ED) with direct transport to the neuroangiography suite may safely shorten reperfusion times.

METHODS

We conducted a single-center retrospective review of consecutive patients transferred to our facility for consideration of endovascular therapy. Patients were identified as admitted directly to the neuroangiography suite (DAN), transferred to the ED before intra-arterial therapy (ED-IA), and transferred to the ED but did not receive IA therapy (ED-IV).

RESULTS

A retrospective review of a prospectively maintained database of transfer patients between January 2013 and October 2016 with large vessel occlusions identified 108 ED-IV patients and 261 patients who underwent mechanical thrombectomy (DAN=111 patients and ED-IA=150 patients). There were no differences in baseline characteristics among the 3 groups. The median computed tomography ASPECTS (Alberta Stroke Program Early CT Score) was lower in the ED-IV group versus the ED-IA and DAN groups (8 versus 9; P=0.001). In the DAN versus ED-IA cohort, there were comparable rates of TICI2b/3 recanalization and access to recanalization time. There was significantly faster hospital arrival to groin access time in the DAN cohort (81 minutes versus 22 minutes; P=0.001). Functional independence at 90 days was comparable in the DAN versus ED-IA cohorts but worse in the ED-IV group (43% versus 44% versus 22%; P=0.001).

CONCLUSIONS

DAN is safe, feasible, and associated with faster times of hospital arrival to recanalization. The clinical benefit of this approach should be assessed in a prospective randomized trial.

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.