Faculty Bibliography

Introduction: The efficacy of MDCT-based-angiography in management of acute stroke and/or emergent-large-vessel-occlusion is well established. However, concern for contrast-induced nephropathy(CIN) especially in patients with major risk factors like Diabetes & Chronic kidney disease often delays rapid evaluation of ELVO patients. Many published studies report the overall incidence of CIN after administration of IV or IA iodinated contrast and highlight the direct correlation of dose on higher incidence of CIN. None, however, have examined impact of sequential IV-IA bolus for neuroangiographic evaluation on renal function in patients with DM and/or CKD. Methods: A retrospective study of our 2015-2017 stroke database of 168 patients was conducted to identify all patients with preexisting DM and/or CKD who developed CIN during their hospital course. We also reviewed the prevalence of dehydration (BUN/Cr <20), CHF and anemia (Hb <8 g/dL) for these patients on admission. Results: For all 168 patients; average IA, IV and cumulative IV-IA contrast (Omnipaque 350) doses within 24 hours were 89.9, 91.7 and 181.6 cc respectively. 68 patients had DM and/or CKD of which 3 developed CIN. Under the definition of >=25% increase in baseline Cr within 72-120 hours of receiving contrast, all 3 had CIN. However, under the definition of >=0.5 mg/dL increase in Cr within 72 hours, none had CIN. All 3 only had preexisting DM as risk factor and had age appropriate baseline Cr on admission. The baseline Cr for each of the 3 patients were 0.82, 1.17 & 0.47 mg/dL respectively while the elevated Cr were 1.03, 1.17 & 0.76 mg/dL respectively. All 3 returned to within baseline by discharge with no mortality or need for hemodialysis. Conclusions: There is low risk of developing CIN in high risk patients like CKD or DM following rapid sequential dual IV/IA contrast bolus in acute stroke patients and therefore should not delay rapid neuro-angiographic evaluation

Introduction: Most stroke/neuro-interventional centers require advanced biplane imaging for evaluation of complex cerebrovascular lesions. Purchasing such equipment is cost-prohibitive for many hospital systems. Additionally, operator-preference often prevents the use of other imaging platforms as a back up for acute neuro-interventional cases. However, most hospitals are often equipped with multiple single plane imaging platforms for IR & Cardiac purposes. Advanced single plane imaging in most catheterization labs provide reasonable penetration and field of view (FOV) for doing acute cases like mechanical thrombectomy. Methods: A retrospective review of our multi-center database of acute stroke patients treated with endovascular therapy was performed. 207 patients were categorized by type of imaging platform on which thrombectomy was performed and relevant angiographic and clinical data was gathered. Primary outcome was measured using angiographic outcome. This included comparisons between two groups of TICI scores: TICI 0-2A vs. TICI 2B-3 and TICI 2B vs. TICI 2C/3. Secondary outcome was safety which was reported as incidence of intracranial hemorrhage between the two groups Results: 146 biplane patients achieved scores of 2B or higher, meanwhile 12 biplane patients received scores of 2A or lower. 44 of 49 single plane patients achieved TICI scores of 2B-3 while 5 had scores of 0-2A, showing no significant difference (p > 0.05). In a second comparison, 97 biplane patients that had outcomes of 2C or 3, and 49 patients with outcomes of 2B; while 29 monoplane patients achieved a score of 2c or 3 and 15 with 2B (p > 0.05). For our secondary measure, ICH in the biplane group was 38/146 and in monoplane group was 9/49, the difference not being statistically significant (p > 0.05) Conclusions: There was no significant difference in safety or efficacy outcomes when comparing thrombectomies performed using biplane vs. monoplane imaging. Thrombectomies performed with either imaging system is equally safe and effective

Introduction: Subclavian steal syndrome (SSS) is usually due to stenosis of the Subclavian Artery (SA) proximal to the origin of the vertebral artery (VA). SSS with intact SA in patients with dialysis arterio-venous fistulas (AVF) has been occasionally reported[1-4]. We present a unique case of the same successfully treated with a covered stent. Methods: A 65-year-old male with DM, HTN, ESRD and left brachial artery- basilic vein fistula (2.27 L/min flow) had multiple admissions with vertebrobasilar symptoms in the setting of elevated BP. Repeated evaluations with CT/CTA/MRI were negative for steno-occlusive disease or infarction. Therefore, symptoms were attributed to hypertensive urgency. On his third presentation in 4 months, he had additional symptoms of left arm pain, weakness and numbness. Signs included left arm hyperemia, warmth and mild motor-sensory deficits. Results: MRA demonstrated reverse flow of blood in left VA with focal stenosis of proximal left SA. Angiogram showed a kinked LSA and rapid/ early shunting to the subcalvian vein. There was no ante-grade visualization of the LVA with reverse flow from the RVA via VB junction. However on compression of the shunt with a BP cuff, antegrade flow in LVA reappeared with disappearance of RVA-LVA steal. BP transduction revealed a 50-mmHg point difference across the kinked segment. Subsequently, proximal left SA was stented with a covered biliary stent resulting in disappearance in RVALVA & LSA-LSV shunts, reappearance of antegrade LVA flow and resolution of symptoms. Conclusions: High-flow AVF is an underdiagnosed cause of symptomatic SSS. We suggest determining AVF flow speeds in any hemodialysis patient who presents with symptoms of posterior circulation insufficiency and obtaining noninvasive vascular studies if flow exceeds 2 L/min or if there has been a recent increase in measured flow during hemodialysis. Obtaining vascular studies with and without fistula compression could be of additional diagnostic utility