Safety of Computed Tomographic Angiography in the Evaluation of Patients With Acute Stroke

Incidence of acute kidney injury in patients with acute ischaemic stroke undergoing CT angiography (CTA) and CT perfusion (CTP): a systematic review and meta-analysis

Background and purpose

We conducted a systematic review and meta-analysis to assess the incidence of acute kidney injury (AKI) in patients undergoing CT angiography (CTA) and CT perfusion (CTP) for acute ischaemic stroke (AIS). Concerns over contrast-induced nephropathy (CIN) often lead medical centres to mandate pre-imaging serum creatinine level assessments, causing unnecessary delays. We aim to confirm further the practice of conducting CTA/CTP without first testing creatinine.

Methods

We searched PubMed, Cochrane Central and Scopus from inception until March 2023 for studies reporting on AKI in patients with AIS receiving CTA/CTP. Outcomes of interest were (1) the odds of AKI in patients receiving CTA/CTP versus non-contrast CT and (2) the overall incidence of AKI and haemodialysis in patients with AIS undergoing CTA/CTP.

Results

Results were pooled using a random effects model. 13 studies were included (5 cohort and 8 single-arm studies) with 5104 patients in total, out of which 4347 patients received CTA/CTP and 757 patients received no contrast. In case-control studies, 4.8% (OR=0.66, 95% CI 0.35 to 1.22, Z=1.32, p=0.19) of patients who received CTA/CTP developed AKI, compared with 7.7% of patients in the control group. Temporary haemodialysis was required for two patients in the analysed studies.

Conclusions

Non-randomised evidence suggests that CTA/CTP is not associated with a statistically significant increase in the risk of AKI in patients with stroke. Further well-designed prospective studies are required to explore potential risk factors of CIN in specific patient populations such as diabetes mellitus and chronic kidney disease.

Minimal Imaging Requirements

The minimal requirements for imaging studies prior to endovascular treatment (EVT) of acute ischemic stroke are those that can provide the information necessary to determine the indication for treatment (treatment triage) and procedural strategies without being time-consuming. An important notion is to determine whether the patient can benefit from EVT. We should recognize that the perfect diagnostic imaging technique does not yet exist, and each has advantages and disadvantages. Generally, stroke imaging protocols to triage for EVT include the following three options: 1) non-contrast CT and CTA, 2) CT perfusion and CTA, and 3) MRI and MRA. It is not known if perfusion imaging or MRI is mandatory for patients with stroke presenting within 6 hours of onset, although non-contrast CT alone has less power to obtain the necessary information. Dual-energy CT can distinguish between post-EVT hemorrhage and contrast agent leakage immediately after EVT.

Best Practice Recommendations for Stroke Vascular Imaging During Iodinated Contrast Shortage

GE Healthcare© announced on April 19, 2022, that their main factory and distributor of iodinated contrast had experienced a temporary shutdown because of COVID-19 outbreak in Shanghai, China. This, along with other supply chain issues, led to a worldwide shortage of iodinated contrast agents, Omnipaque and Visipaque. Our Comprehensive Stroke Center was confronted with the cascading effect of this iodinated contrast material shortage. We took immediate steps to revise our protocols and processes to continue to provide high-quality care to our stroke patients. A multidisciplinary working group comprised of representatives of our stroke center, including vascular neurology, diagnostic neuroradiology, and neurovascular surgery, urgently met to brainstorm how to mitigate the shortage. We established parameters and local guidelines for the use of CT angiography, CT perfusion, and digital subtraction angiography for stroke patients. In this article, we propose "best practice" recommendations from a single Joint Commission approved Comprehensive Stroke Center that can be used as blueprint by other hospital systems when navigating potential future supply chain issues, to provide consistent high-quality stroke care.

Contrast-associated acute kidney injury in acute ischemic stroke patients following multi-dose iodinated contrast

BACKGROUND AND OBJECTIVE

lthough intravenous contrast in neuroimaging has become increasingly important in selecting patients for stroke treatment, clinical concerns remain regarding contrast-associated acute kidney injury (CA-AKI). Given the increasing utilization of CT angiography and/or perfusion coupled with cerebral angiography, the purpose of this study was to assess the association of CA-AKI and multi-dose iodinated contrast in acute ischemic stroke (AIS) patients.

MATERIALS AND METHODS

etrospective review of AIS patients at a comprehensive stroke center was performed from January 2018 to December 2019. Data collection included patient demographics, stroke risk factors, stroke severity, discharge disposition, modified Rankin Scale, contrast type/volume, and creatinine levels (baseline, 48-72 h). CA-AKI was defined as creatinine increase ≥ 25 % from baseline. Bivariate analyses and multivariable logistic regression models were implemented to compare AIS patients with multi-dose and single-dose contrast.

RESULTS

Of 440 AIS patients, 215 (48.9 %) were exposed to a single-dose contrast, and 225 (51.1 %) received multi-dose. In single-dose patients, CA-AKI at 48/72 h was 9.7 %/10.2 % compared to 8.0 %/8.9 % in multi-dose patients. Multi-dose patients were significantly more likely to receive a higher volume of contrast (mean 142.1 mL versus 80.8 mL; p < 0.001), but there was no significant difference in their creatinine levels or CA-AKI. NIHSS score (OR=1.08, 95 % CI=[1.04,1.13]), and patient transfer from another hospital (OR=3.84, 95 % CI=[1.94,7.62]) were significantly associated with multi-dose contrast.

CONCLUSIONS

No significant association between multi-dose iodinated contrast and CA-AKI was seen in AIS patients. Concerns of CA-AKI should not deter physicians from pursuing timely and appropriate contrast-enhanced neuroimaging that may optimize treatment outcomes in AIS patients.

Indian College of Radiology and Imaging (ICRI) Consensus Guidelines for the Early Management of Patients with Acute Ischemic Stroke: Imaging and Intervention

The medical science has witnessed significant change in the management of acute stroke patients as a result of recent advances in the field of stroke imaging and endovascular mechanical thrombectomy in addition to intravenous thrombolysis and optimization of stroke services in balance with available resources. Despite initial negative trials, we witnessed the publication of five multicenter randomized clinical trials showing superiority of the endovascular approach over standard medical management in patients with large vessel occlusion. The aim of this study is to provide comprehensive set of evidence-based recommendations regarding imaging and endovascular interventions in acute ischemic stroke patients.

Multimodality Imaging in Acute Ischemic Stroke

Stroke is the most common cause of mortality and morbidity worldwide. The prognosis of stroke depends upon the area affected and its early treatment. Time is of the essence in the care of stroke patients as it is estimated that approximately 1.9 million neurons, 14 billion synapses, and 12 km myelinated nerve fibers are lost per minute. Therefore, early diagnosis and prompt treatment are necessary. The primary goal of imaging in acute stroke is to diagnose the underlying cause, estimate the area affected, predict response towards thrombolytic therapy and to exclude the conditions mimicking stroke. With advancements in radiology, multiple imaging modalities are available for diagnosis and predicting prognosis. None of them is considered alone to be perfect. In this era of multimodality imaging, the decision of choosing appropriate techniques depends upon purpose and availability. Non-Contrast Computed Tomography is time effective, and helps in excluding other causes, Trans Cranial Doppler is time-effective and cost-effective with wide availability, however, is operator dependent and less sensitive. It holds a great future in sonothrombolysis. Magnetic Resonance Imaging is so far considered to be the most superior one in terms of early diagnosis, planning for interventional treatment and predicting the response of treatment. However, it is limited due to high cost and lack of availability. The current review gives a detailed account of all imaging modalities available for imaging stroke and their associated pros and cons.

Renal Safety of Multimodal Brain Imaging Followed by Endovascular Therapy

BACKGROUND AND PURPOSE

Contrast-enhanced noninvasive angiography and perfusion imaging are recommended to identify eligible patients for endovascular therapy (EVT) in extended time windows (>6 hours or wake-up). If eligible, additional intraarterial contrast exposure will occur during EVT. We aimed to study the renal safety in the DEFUSE 3 (Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke) population, selected with contrast-enhanced multimodal Imaging and randomized to EVT versus medical management.

METHODS

In the randomized DEFUSE 3 trial population, we compared changes in serum creatinine between baseline (before randomization) and 24 hours later. The primary outcome was the relative change in creatinine level between baseline and 24 hours in the EVT versus medical arm. The secondary outcome was a comparison between computed tomography (CT) versus magnetic resonance imaging selection in the EVT arm. The safety outcome was a comparison of the proportion of patients with criteria for contrast-associated kidney injury in the EVT versus medical arm and a comparison between CT versus magnetic resonance imaging selection in the EVT arm.

RESULTS

In the DEFUSE 3 population (n=182, age 69±13, 51% female), mean creatinine decreased from a baseline of 0.98±0.33 mg/dL to 0.88±0.28 mg/dL at 24 hours (P<0.001). There was no difference in change between treatment groups: relative to baseline, there was a 6.3% reduction in the EVT group versus 9.2% in the medical group, P=0.294. Absolute decrease -0.08±0.18 in EVT versus -0.12±0.18 in medical, P=0.135; Among patients treated with EVT, there was no difference in 24-hour creatinine level changes between patients who were selected with CT angiography/CT perfusion (-0.08±0.18) versus magnetic resonance imaging (-0.07±0.19), P=0.808 or 6.8% reduction versus 4.8%, P=0.696. In the EVT arm, contrast-associated kidney injury was encountered in 4 out of 91 (4.4%) versus 2/90 (2.2%) in the medical arm P=0.682. In the EVT arm, contrast-associated kidney injury was evenly distributed between magnetic resonance imaging (1/22, 4.6%) versus CT 3 out of 69 (4.4%), P=1.0.

CONCLUSIONS

Perfusion imaging before EVT was not associated with evidence of decline in renal function. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02586415.

Impact of creatinine screening on contrast-induced nephropathy following computerized tomography for stroke

OBJECTIVE

This study sought to evaluate rates of acute kidney injury in patients undergoing contrast-enhanced computerized tomography for acute stroke in the emergency department (ED) before and after the cessation of creatinine screening.

METHODS

This retrospective study compared ED patients receiving contrast-enhanced imaging for suspected acute stroke with and without protocolized creatinine screening. The primary outcome was CIN, defined as an increase in serum creatinine of 0.3 mg/dl within 48 hours or 50% above baseline within 7 days after contrast administration. Secondary outcomes consisted of CIN based on other definitions, renal impairment greater than 30 days from contrast administration, hemodialysis, and mortality. Outcomes were compared using difference of proportions and odds ratios with 95% confidence intervals.

RESULTS

This study included 382 subjects, with 186 and 196 in the screening and post-screening cohorts, respectively. No significant differences were observed for CIN (7.0% vs 7.1%, difference 0.1% [95% CI -5.6-5.1%], OR 1.02 [95% CI 0.47-2.24]), renal impairment greater than 30 days post-contrast (8.4% vs 7.5%, OR 0.88 [0.38-2.07]), or mortality (index visit: 4.8% vs 2.6%, OR 0.51 [0.17-1.57], 90-day follow-up: 6.7% vs 4.0%, OR 0.58 [0.22-1.53]). No patients from either group required hemodialysis.

CONCLUSIONS

The elimination of creatinine screening prior to obtaining contrast-enhanced computerized tomography in patients with suspected acute stroke did not adversely affect rates of CIN, hemodialysis, or mortality at a comprehensive stroke center.

Acute Kidney Injury after Endovascular Treatment in Patients with Acute Ischemic Stroke

Acute kidney injury (AKI) is often associated with the use of contrast agents. We evaluated the frequency of AKI, factors associated with AKI after endovascular treatment (EVT), and associations with AKI and clinical outcomes. We retrospectively analyzed consecutively enrolled patients with acute ischemic stroke who underwent EVT at three stroke centers in Korea. We compared the characteristics of patients with and without AKI and independent factors associated with AKI after EVT. We also investigated the effects of AKI on functional outcomes and mortality at 3 months. Of the 601 patients analyzed, 59 patients (9.8%) developed AKI and five patients (0.8%) started renal replacement therapy after EVT. In the multivariate analysis, diabetes mellitus (odds ratio (OR), 2.341; 95% CI, 1.283–4.269; p = 0.005), the contrast agent dose (OR, 1.107 per 10 mL; 95% CI, 1.032–1.187; p = 0.004), and unsuccessful reperfusion (OR, 1.909; 95% CI, 1.019–3.520; p = 0.040) were independently associated with AKI. The presence of AKI was associated with a poor functional outcome (OR, 5.145; 95% CI, 2.177–13.850; p < 0.001) and mortality (OR, 8.164; 95% CI, 4.046–16.709; p < 0.001) at 3 months. AKI may also affect the outcomes of ischemic stroke patients undergoing EVT. When implementing EVT, practitioners should be aware of these risk factors.

Contrast-Induced Acute Kidney Injury in Radiologic Management of Acute Ischemic Stroke in the Emergency Setting

BACKGROUND AND PURPOSE

The use of invasive cerebral angiography with CTA for active treatment of patients with suspected ischemic strokes has been increasing recently. This study aimed to identify the incidence of postcontrast acute kidney injury using baseline renal function when CTA and cerebral angiography were performed sequentially.

MATERIALS AND METHODS

This retrospective observational study evaluated adults (18 years of age or older) with ischemic stroke who underwent CTA and cerebral angiography sequentially between 2010 and 2018. The incidence of postcontrast acute kidney injury was determined using the baseline estimated glomerular filtration rate. The value of the baseline estimated glomerular filtration rate at which the occurrence of postcontrast acute kidney injury increased was also determined.

RESULTS

Postcontrast acute kidney injury occurred in 57/601 (9.5%) patients. Those with a baseline estimated glomerular filtration rate of <30 mL/min/1.73 m² showed a higher incidence of acute kidney injury. Age, chronic kidney disease, medication (nonsteroidal anti-inflammatory drugs, angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, β blockers, statins, and insulin) use following contrast media exposure, and serum albumin affected the incidence of postcontrast acute kidney injury. The incidence of postcontrast acute kidney injury increased when the baseline estimated glomerular filtration rate was <43 mL/min/1.73 m².

CONCLUSIONS

Patients with low baseline renal function had the highest incidence of postcontrast acute kidney injury after CTA and cerebral angiography, but no fatal adverse effects were documented. Thus, patients suspected of having a stroke should be actively managed with respect to neurovascular function.

Management of acute ischemic stroke

Stroke is the leading cause of long term disability in developed countries and one of the top causes of mortality worldwide. The past decade has seen substantial advances in the diagnostic and treatment options available to minimize the impact of acute ischemic stroke. The key first step in stroke care is early identification of patients with stroke and triage to centers capable of delivering the appropriate treatment, as fast as possible. Here, we review the data supporting pre-hospital and emergency stroke care, including use of emergency medical services protocols for identification of patients with stroke, intravenous thrombolysis in acute ischemic stroke including updates to recommended patient eligibility criteria and treatment time windows, and advanced imaging techniques with automated interpretation to identify patients with large areas of brain at risk but without large completed infarcts who are likely to benefit from endovascular thrombectomy in extended time windows from symptom onset. We also review protocols for management of patient physiologic parameters to minimize infarct volumes and recent updates in secondary prevention recommendations including short term use of dual antiplatelet therapy to prevent recurrent stroke in the high risk period immediately after stroke. Finally, we discuss emerging therapies and questions for future research.

Brain-kidney interaction: Renal dysfunction following ischemic stroke

Stroke is a leading cause of mortality and morbidity, with long-term debilitating effects. Accumulating evidence from experimental studies as well as observational studies in patients suggests a cross talk between the brain and kidney after stroke. Stroke may lead to kidney dysfunction which can adversely impact patient outcome. In this review article, we discuss the epidemiology and mechanisms of brain–kidney interaction following ischemic stroke. Specifically, we discuss the role of the central autonomic network, autoregulation, inflammatory and immune responses, the role of extracellular vesicles and their cargo microRNA, in mediating brain–kidney interaction following stroke. Understanding the bidirectional nature of interaction between the brain and kidney after cerebral injury would have clinical implications for the treatment of stroke and overall patient outcome.

Contrast-Associated Acute Kidney Injury in Endovascular Thrombectomy Patients With and Without Baseline Renal Impairment

Background and Purpose—

In ischemic stroke, baseline renal impairment is present in 20 to 35% of patients and may increase the risk of contrast-associated acute kidney injury (CA-AKI). We aimed to determine whether endovascular thrombectomy (EVT) patients with baseline renal impairment are at increased risk of CA-AKI.

Methods—

Consecutive EVT patients were identified from a prospective database. Patients were stratified by estimated glomerular filtration rate. The primary outcome was CA-AKI assessed at 24 to 72 hours following EVT, defined as an increase in serum creatinine of ≥26.5 µmol/L or 1.5× baseline serum creatinine. Secondary outcomes included requirement for renal replacement therapy and 3-month mortality.

Results—

Three hundred thirty-three EVT patients (201 men; mean±SD age 63.9±15.8 years) were included. The mean±SD iohexol contrast volume used in diagnostic and EVT imaging was 236±77 mL per patient. CA-AKI occurred in 11 (3.3%) patients; none required renal replacement therapy, but 4 of 11 (36.4%) had died by 3 months. Propensity score–adjusted logistic regression showed that estimated glomerular filtration rate <30 mL/(min·1.73 m 2 ) was a significant predictor of CA-AKI (odds ratio, 19.93; 95% CI, 2.33–170.74; P =0.006). The dose of contrast was not associated with an increased risk of CA-AKI ( P >0.05). Multiple logistic regression adjusted for potential confounders demonstrated that CA-AKI was independently associated with increased mortality (odds ratio, 4.68; 95% CI, 1.05–20.97; P =0.04).

Conclusions—

There is utility in obtaining baseline creatinine levels to identify patients at risk of CA-AKI and to establish a diagnosis of CA-AKI in patients with subsequent creatinine rises. However, contrast-requiring diagnostic imaging and EVT should not be delayed by waiting for the results of baseline renal function.

Guidelines for the Early Management of Patients With Acute Ischemic Stroke: 2019 Update to the 2018 Guidelines for the Early Management of Acute Ischemic Stroke: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association

Background and Purpose- The purpose of these guidelines is to provide an up-to-date comprehensive set of recommendations in a single document for clinicians caring for adult patients with acute arterial ischemic stroke. The intended audiences are prehospital care providers, physicians, allied health professionals, and hospital administrators. These guidelines supersede the 2013 Acute Ischemic Stroke (AIS) Guidelines and are an update of the 2018 AIS Guidelines. Methods- Members of the writing group were appointed by the American Heart Association (AHA) Stroke Council's Scientific Statements Oversight Committee, representing various areas of medical expertise. Members were not allowed to participate in discussions or to vote on topics relevant to their relations with industry. An update of the 2013 AIS Guidelines was originally published in January 2018. This guideline was approved by the AHA Science Advisory and Coordinating Committee and the AHA Executive Committee. In April 2018, a revision to these guidelines, deleting some recommendations, was published online by the AHA. The writing group was asked review the original document and revise if appropriate. In June 2018, the writing group submitted a document with minor changes and with inclusion of important newly published randomized controlled trials with >100 participants and clinical outcomes at least 90 days after AIS. The document was sent to 14 peer reviewers. The writing group evaluated the peer reviewers' comments and revised when appropriate. The current final document was approved by all members of the writing group except when relationships with industry precluded members from voting and by the governing bodies of the AHA. These guidelines use the American College of Cardiology/AHA 2015 Class of Recommendations and Level of Evidence and the new AHA guidelines format. Results- These guidelines detail prehospital care, urgent and emergency evaluation and treatment with intravenous and intra-arterial therapies, and in-hospital management, including secondary prevention measures that are appropriately instituted within the first 2 weeks. The guidelines support the overarching concept of stroke systems of care in both the prehospital and hospital settings. Conclusions- These guidelines provide general recommendations based on the currently available evidence to guide clinicians caring for adult patients with acute arterial ischemic stroke. In many instances, however, only limited data exist demonstrating the urgent need for continued research on treatment of acute ischemic stroke.

Risk of Acute Kidney Injury with Consecutive, Multidose Use of Iodinated Contrast in Patients with Acute Ischemic Stroke

Currently, CTA is the imaging technique most frequently used to evaluate acute ischemic stroke, and patients with intracranial large-vessel occlusion usually undergo endovascular treatment. This single-center, prospective, cohort study showed that consecutive, multidose use of contrast during CTA and DSA does not increase the incidence of acute kidney injury in patients with acute ischemic stroke, though acute kidney injury tended to have a higher incidence in the contrast multiexposure group (P = .172).

2018 Guidelines for the Early Management of Patients With Acute Ischemic Stroke: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association

BACKGROUND AND PURPOSE

The purpose of these guidelines is to provide an up-to-date comprehensive set of recommendations for clinicians caring for adult patients with acute arterial ischemic stroke in a single document. The intended audiences are prehospital care providers, physicians, allied health professionals, and hospital administrators. These guidelines supersede the 2013 guidelines and subsequent updates.

METHODS

Members of the writing group were appointed by the American Heart Association Stroke Council's Scientific Statements Oversight Committee, representing various areas of medical expertise. Strict adherence to the American Heart Association conflict of interest policy was maintained. Members were not allowed to participate in discussions or to vote on topics relevant to their relations with industry. The members of the writing group unanimously approved all recommendations except when relations with industry precluded members voting. Prerelease review of the draft guideline was performed by 4 expert peer reviewers and by the members of the Stroke Council's Scientific Statements Oversight Committee and Stroke Council Leadership Committee. These guidelines use the American College of Cardiology/American Heart Association 2015 Class of Recommendations and Levels of Evidence and the new American Heart Association guidelines format.

RESULTS

These guidelines detail prehospital care, urgent and emergency evaluation and treatment with intravenous and intra-arterial therapies, and in-hospital management, including secondary prevention measures that are appropriately instituted within the first 2 weeks. The guidelines support the overarching concept of stroke systems of care in both the prehospital and hospital settings.

CONCLUSIONS

These guidelines are based on the best evidence currently available. In many instances, however, only limited data exist demonstrating the urgent need for continued research on treatment of acute ischemic stroke.

Acute Kidney Injury After Computed Tomography: A Meta-analysis

STUDY OBJECTIVE

Computed tomography (CT) is an important imaging modality used in the diagnosis of a variety of disorders. Imaging quality may be improved if intravenous contrast is added, but there is a concern for potential renal injury. Our goal is to perform a meta-analysis to compare the risk of acute kidney injury, need for renal replacement, and total mortality after contrast-enhanced CT versus noncontrast CT.

METHODS

We searched MEDLINE (PubMed), the Cochrane Library, CINAHL, Web of Science, ProQuest, and Academic Search Premier for relevant articles. Included articles specifically compared rates of renal insufficiency, need for renal replacement therapy, or mortality in patients who received intravenous contrast versus those who received no contrast.

RESULTS

The database search returned 14,691 articles, inclusive of duplicates. Twenty-six unique articles met our inclusion criteria, with an additional 2 articles found through hand searching. In total, 28 studies involving 107,335 participants were included in the final analysis, all of which were observational. Meta-analysis demonstrated that, compared with noncontrast CT, contrast-enhanced CT was not significantly associated with either acute kidney injury (odds ratio [OR] 0.94; 95% confidence interval [CI] 0.83 to 1.07), need for renal replacement therapy (OR 0.83; 95% CI 0.59 to 1.16), or all-cause mortality (OR 1.0; 95% CI 0.73 to 1.36).

CONCLUSION

We found no significant differences in our principal study outcomes between patients receiving contrast-enhanced CT versus those receiving noncontrast CT. Given similar frequencies of acute kidney injury in patients receiving noncontrast CT, other patient- and illness-level factors, rather than the use of contrast material, likely contribute to the development of acute kidney injury.

Evaluation and Management of Atherosclerotic Carotid Stenosis

Medical therapies for the prevention of stroke have advanced considerably in the past several years. There can also be a role for mechanical restoration of the lumen by endarterectomy or stenting in selected patients with high-grade atherosclerotic stenosis of the extracranial carotid artery. Endarterectomy is generally recommended for patients with high-grade symptomatic carotid stenosis. Stenting is considered an option for patients at high risk of complications with endarterectomy. Whether revascularization is better than contemporary medical therapy for asymptomatic extracranial carotid stenosis is a subject of several ongoing randomized clinical trials in the United States and internationally.

Neurons Over Nephrons: Systematic Review and Meta-Analysis of Contrast-Induced Nephropathy in Patients With Acute Stroke

BACKGROUND AND PURPOSE

Because of the perceived risk of contrast-induced acute kidney injury (AKI), many centers require pre-imaging serum creatinine levels, potentially delaying care. We performed a systematic review and meta-analysis evaluating AKI rates in patients with acute ischemic stroke receiving computed tomographic angiography (CTA) and computed tomographic perfusion (CTP).

METHODS

We searched MEDLINE, EMBASE, and the Web of Science through December 2016 for studies reporting on AKI in patients with acute ischemic stroke receiving CTA/CTP. Using a random-effects model, estimates were pooled across studies. Outcomes of interest were (1) the odds of AKI in patients receiving CTA/CTP versus noncontrast computed tomography, (2) overall rate of AKI and hemodialysis in patients with acute ischemic stroke undergoing CTA/CTP, and (3) the odds of CTA/CTP-associated AKI among patients with and without chronic kidney disease.

RESULTS

Fourteen studies were included (6 case-control studies and 8 single-arm studies) with 5727 CTA/CTP and 981 noncontrast computed tomography patients. In case-control studies, AKI was significantly lower among CTA/CTP patients compared with noncontrast computed tomography patients (odds ratio=0.47; 95% confidence interval=0.33-0.68; P<0.01). Adjusting for baseline creatinine, there was no difference in AKI rates between groups (odds ratio=0.34; 95% confidence interval=0.10-1.21). The overall rate of AKI in CTA/CTP patients was 3% (95% confidence interval=2%-4%). The overall rate of hemodialysis in the CTA/CTP group was 0.07% (3 of 4373). There was no difference in AKI among CTA/CTP patients with and without chronic kidney disease (odds ratio=0.63; 95% confidence interval=0.34-1.12).

CONCLUSIONS

Nonrandomized evidence suggests that CTA/CTP are not associated with statistically significant increase in risk of AKI in patients with stroke, even those with known chronic kidney disease.