Comprehensive Analysis of Neurologic Complications following Transradial Cerebral Angiography

Patient Demographics

We conducted a retrospective analysis of prospectively collected data from a single institution between January 2018 and December 2020. Excluding cases of transfemoral diagnostic cerebral angiography, a total of 1902 consecutive transradial diagnostic cerebral angiography cases were included. Neurologic complications occurred in 19 cases (1.0%). The exclusion criteria were 1) spinal angiography or venography, 2) transradial angiography with therapeutic procedures, and 3) emergency angiography for hemorrhagic stroke. For patients without neurologic complications, only their initial examination was considered. In cases in which multiple cerebral angiographies were performed before or after experiencing a neurologic complication, only the examination in which the first such complication occurred was included.

After applying the exclusion criteria, 1679 cases were eligible for inclusion and were categorized into 2 groups based on the occurrence of neurologic complications (1660 cases in the control group and 19 cases in the neurologic complication group). Clinical and radiologic data were collected from electronic medical records and a prospectively maintained transradial diagnostic cerebral angiography database. Our study on neurologic complications following transradial cerebral angiography encompassed 4 critical dimensions: quantifying their occurrence rate, exploring associated risk factors, detailing their clinical manifestations, and characterizing their distinct DWI patterns.

This observational cohort study adhered to the principles outlined in the Strengthening the Reporting of Observational Studies in Epidemiology statement for observational studies (Supplemental Data).⁹ The study was conducted in accordance with the Declaration of Helsinki, approved by our institutional review board, and granted a waiver for informed consent (subject number: HC22RASI0094).

Definition of Predictive Factors Contributing to Neurologic Complications

Predictive factors for neurologic complications after transradial cerebral angiography were classified and analyzed based on clinical, angiographic, and anatomic criteria. The specific factors collected are outlined in the Table. Clinical factors included patient demographics (sex, age); procedure indications (aneurysm, atherosclerotic cerebrovascular disease, Moyamoya disease, vascular malformation, dissection, tumor); medical history (hypertension, diabetes mellitus, dyslipidemia, chronic kidney disease, cardiac disease, prior stroke, smoking); and laboratory parameters (hemoglobin, white blood cell count, platelet count, blood urea nitrogen, creatinine, coagulation profiles—prothrombin time, activated partial thromboplastin time, and lipid panels—total cholesterol, triglycerides, high-density lipoprotein, and low-density lipoprotein). Atherosclerotic cerebrovascular disease includes transient ischemic attack, ischemic stroke, intracranial atherosclerotic stenosis (ICAS), and extracranial atherosclerotic stenosis. Laboratory data were taken from the most recent values available on the day of angiography or before the procedure. Abnormal values were defined as any result outside the reference range, regardless of whether above or below normal limits. The number of cases with abnormal values was recorded. Clinical factors also included prior interventions, such as a history of extracranial or intracranial stent placements, prior craniotomies, and the number of DSA procedures previously conducted.

Angiographic factors included the duration of the procedure, the number of vessels examined, the number of selective angiographies performed, and whether a 3D rotational angiography was conducted.

Anatomic factors covered the type of aortic arch, the angulation of the right subclavian artery (SCA), and stenosis in both extracranial arteries (including the right SCA, proximal ICA, and vertebral artery orifice [VAO]) and intracranial arteries. The definitions of anatomic factors are as follows: 1) the type of aortic arch was classified into 3 groups according to the classification by Casserly et al¹⁰; 2) the angulation of the right subclavian artery was categorized as normal, tortuosity, kinking, or looping according to the modified criteria of Weibel and Fields¹¹ and Metz et al¹² (angulation was defined as angle between vessel segment: tortuosity ≥60°, kinking 30°–60°, looping <30°); and 3) the degree of stenosis in both extracranial and intracranial arteries, excluding the proximal ICA, was measured by using the Warfarin-Aspirin Symptomatic Intracranial Disease method,¹³ with stenosis defined as >50%. For the proximal ICA, stenosis was assessed by using the NASCET method,¹⁴ also defined as >50%. Anatomic data were collected from contrast-enhanced MRA or CTA performed within 3 months of the procedure.

Definition of Neurologic Complications and DWI Patterns

The study investigated the characteristics of neurologic complications following transradial cerebral angiography including frequency, onset timing, symptoms, duration, and prognosis. Neurologic complications were defined as any alteration in the patient’s neurologic status after cerebral angiography, confirmed by identifying cerebral infarction on DWI. DWI was conducted only when symptoms of neurologic complications emerged to confirm the presence of lesions. Complications were classified as transient, reversible, or persistent based on symptom duration. Transient complications were those that resolved within 24 hours after the examination. Reversible complications persisted for more than 24 hours but resolved within 7 days. Persistent complications were those that extended beyond 7 days. Patients were admitted on a 2-night, 3-day schedule, allowing for structured preprocedural preparation and postprocedural monitoring. When neurologic complications occurred, the hospital stay was extended based on clinical need. For asymptomatic patients, a follow-up visit was conducted 1 month after the angiography to confirm the absence of delayed symptom onset. For symptomatic patients, the prognosis was evaluated by using the mRS score obtained 3 months after the onset of neurologic complications.

The study also analyzed the distribution and patterns of lesions on DWI in cerebral infarction cases following transradial cerebral angiography. DWI was categorized into cortical/subcortical, white matter/perforator, territorial, and mixed patterns based on anatomic and physiologic features. The distribution of DWI lesions was classified by the affected vascular territories, including the anterior cerebral artery (ACA), MCA, posterior cerebral artery (PCA), and vertebrobasilar artery (VBA). Lesions spanning 2 or more vascular territories were classified as “Multiple.” The study also investigated the multiplicity of lesions and their characteristics, defining multiplicity as the presence of multiple diffusion-restricted lesions on DWI, whether confined to a single vascular territory or spread across several. If multiple lesions were present, they were classified as bilateral or unilateral, depending on whether they involved 1 or both hemispheres. For unilateral lesions, dominance was examined to identify the predominant lateralization, indicating a preference for either the right or left hemisphere. Additionally, bicirculation involvement, defined as the simultaneous presence of lesions in both anterior and posterior circulations, was assessed.

Radial Angiography Technique

The angiographic method of TRA used in our study mirrored those in previous research.^1,5 All patients scheduled for angiography were admitted to the hospital the day before the procedure for thorough preparation. To lower the risk of ischemic complications, aspirin 100 mg and Plavix 75 mg were administered daily for 1 week before the procedure at the discretion of the attending physician. The radial artery served as the access point for all transradial angiography cases. A 5F Glidesheath Slender (Terumo Interventional Systems) 7 cm introducer sheath, a 5F Radifocus Glidecath Simmons/Sidewinder type 2 catheter (Cook), and a 0.035-inch Radifocus guidewire (Terumo Interventional Systems) were the primary tools used. After local anesthesia with 1% lidocaine, the radial artery was punctured by using a 20-gauge needle with a modified Seldinger technique. Once the 5F introducer sheath was in place, a nitroglycerine solution (1 mg/mL; 1 mL mixed in 49 mL of normal saline) was infused through the side port of the introducer to prevent radial artery spasm. A dose of 2000 IU of IV heparin was administered systemically, unless contraindicated due to underlying medical conditions, to prevent thrombosis. Continuous catheter flushing with heparinized saline was routinely used in all cases to maintain patency and prevent thromboembolic events. Iodixanol 320 mg/mL (Visipaque, GE Healthcare), a nonionic, dimeric, water-soluble contrast medium, was used for angiography. The technique for folding the Simmons catheter curve was consistent with the conventional method, involving catheter placement in the descending thoracic aorta or folding the Simmons catheter curve within the ascending aorta.¹⁵ All cerebral angiography procedures were performed by attending physicians or by fellows under direct attending supervision.

Statistical Analysis

In line with findings observed in studies of transfemoral cerebral angiography,^16,17 neurologic complications following transradial angiography are infrequent. To address potential bias stemming from the limited sample size, a case-control matching analysis was performed. Cases and controls were matched at a 1:4 ratio to ensure a well-balanced comparison by using the greedy algorithm and a macro developed by Kosanke and Bergstralh.¹⁸ The variables used for matching included demographic and clinical covariates such as age, sex, history of hypertension, diabetes mellitus, dyslipidemia, chronic kidney disease, heart disease, ischemic stroke, smoking status, and antiplatelet medication use. For age, a match was defined as a difference of 5 years or less. Descriptive statistics for demographic characteristics were calculated both before and after matching. Before matching, comparative analyses of patient and angiographic characteristics were done by using the χ² test or Fisher exact test for categoric variables and an independent t test for continuous variables. After matching, McNemar test was used for categoric variables, and paired t tests for continuous variables. Continuous variables were presented as mean ± standard deviation or median (first and third quartiles), and categoric variables as frequencies and percentages.

The association between neurologic complications following transradial cerebral angiography and predictive angiographic factors was evaluated by using conditional logistic regression, accounting for the matched design. ORs and their 95% CIs were calculated. Statistical tests were 2-sided, and P values < .05 were considered significant. All analyses, including matching analysis, were performed by using SAS Version 9.4 (SAS Institute).