Loay Kabbani

Clinical utility of carotid duplex ultrasound prior to cardiac surgery

OBJECTIVE Clinical utility and cost-effectiveness of carotid duplex examination prior to cardiac surgery have been questioned by the multidisciplinary committee creating the 2012 Appropriate Use Criteria for Peripheral Vascular Laboratory Testing. We report the clinical outcomes and postoperative neurologic symptoms in patients who underwent carotid duplex ultrasound prior to open heart surgery at a tertiary institution. METHODS Using the combined databases from our clinical vascular laboratory and the Society of Thoracic Surgery, a retrospective analysis of all patients who underwent carotid duplex ultrasound within 13 months prior to open heart surgery from March 2005 to March 2013 was performed. The outcomes between those who underwent carotid duplex scanning (group A) and those who did not (group B) were compared. RESULTS Among 3233 patients in the cohort who underwent cardiac surgery, 515 (15.9%) patients underwent a carotid duplex ultrasound preoperatively, and 2718 patients did not (84.1%). Among the patients who underwent carotid screening vs no screening, there was no statistically significant difference in the risk factors of cerebrovascular disease (10.9% vs 12.7%; P = .26), prior stroke (8.2% vs 7.2%; P = .41), and prior transient ischemic attack (2.9% vs 3.3%; P = .24). For those undergoing isolated coronary artery bypass grafting (CABG), 306 (17.8%) of 1723 patients underwent preoperative carotid duplex ultrasound. Among patients who had carotid screening prior to CABG, the incidence of carotid disease was low: 249 (81.4%) had minimal or mild stenosis (<50%); 25 (8.2%) had unilateral moderate stenosis (50%-69%); 10 (3.3%) had bilateral moderate stenosis; 9 (2.9%) had unilateral severe stenosis (70%-99%); 5 (1.6%) had contralateral moderate stenosis; 2 (0.7%) had bilateral severe stenosis; 4 (1.3%) had unilateral occluded with contralateral less than 50% stenosis, 1 (0.3%) had unilateral occluded with contralateral (70%-99%) stenosis; and 1 had bilateral occluded carotid arteries. Primary outcomes of patients who underwent isolated CABG showed no difference in the perioperative mortality (2.9% vs 4.3%; P = .27) and stroke (2.9% vs 2.6%; P = .70) between patients undergoing preoperative duplex scanning and those who did not. Primary outcomes of patients who underwent open heart surgery also showed no difference in the perioperative mortality (5.1% vs 6.9%; P = .14) and stroke (2.6% vs 2.4%; P = .85) between patients undergoing preoperative duplex scanning and those who did not. Operative intervention of severe carotid stenosis prior to isolated CABG occurred in 2 of the 17 patients (11.8%) identified who underwent carotid endarterectomy with CABG. CONCLUSIONS In this study, the correlation between preoperative duplex-documented high-grade carotid stenosis and postoperative stroke was low. Prudent use of preoperative carotid duplex ultrasound should be based on the presence of cerebrovascular symptoms and the type of open heart surgery.

Self-assembled Collagen-Fibrin Hydrogel Reinforces Tissue Engineered Adventitia Vessels Seeded with Human Fibroblasts

Efforts for tissue engineering vascular grafts focuses on the tunica media and intima, although the tunica adventitia serves as the primary structural support for blood vessels. In surgery, during endarterectomies, surgeons can strip the vessel, leaving the adventitia as the main strength layer to close the vessel. Here, we adapted our recently developed technique of forming vascular tissue rings then stacking the rings into a tubular structure, to accommodate human fibroblasts to create adventitia vessels in 8 days. Collagen production and fibril cross-linking was augmented with TGF-β and ascorbic acid, significantly increasing tensile strength to 57.8 ± 3.07 kPa (p = 0.008). Collagen type I gel was added to the base fibrin hydrogel to further increase strength. Groups were: Fibrin only; 0.7 mg/ml COL; 1.7 mg/ml COL; and 2.2 mg/ml COL. The 0.7 mg/ml collagen rings resulted in the highest tensile strength at 77.0 ± 18.1 kPa (p = 0.015). Culture periods of 1–2 weeks resulted in an increase in extracellular matrix deposition and significantly higher failure strength but not ultimate tensile strength. Histological analysis showed the 0.7 mg/ml COL group had significantly more, mature collagen. Thus, a hydrogel of 0.7 mg/ml collagen in fibrin was ideal for creating and strengthening engineered adventitia vessels.

Postoperative urinary retention in men is common after carotid endarterectomy and is associated with advanced age and prior urinary tract infection.

OBJECTIVE This study was undertaken to analyze the occurrence of postoperative urinary retention (POUR) after carotid endarterectomy (CEA) and determine whether there are any associated modifiable risk factors. CEA was chosen to minimize the confounding effects of known risk factors for POUR, including immobilization, regional and severe pain, and neuroaxial anesthesia. METHODS This was a retrospective record review of 186 male patients undergoing CEA between 2007 and 2011. Demographic, comorbidities, and operative characteristics were compared. Continuous variables are reported as median and interquartile range (IQR) and categoric variables as frequencies and proportions. Pearson χ(2) or Mann-Whitney U tests compared categoric and continuous variables, respectively. Logistic regression was used to examine univariate and multivariate odds of POUR. Multivariate analysis controlled for known predictors of urinary retention. Association with other complications was examined with the Pearson correlation coefficient. RESULTS POUR occurred in 34 patients (18.3%). Median age and history of urinary tract infection (UTI) were significantly associated with POUR: median age was 73.0 years (IQR, 67-80 years) for those with POUR vs 69.5 years (IQR, 63-76 years) for those without (P = .047); 17.6% of patients with a history of UTI developed POUR vs 5.9% without (P = .023). These findings persisted on multivariate analysis controlling for known predictors of POUR (body mass index, history of diabetes, benign prostate hyperplasia, and prior prostate surgery): median age (odds ratio, 1.05; 95% confidence interval, 1-1.1) and history of UTI (odds ratio, 4.16; 95% confidence interval, 1.23-14.05; P = .022). The occurrence of POUR was significantly correlated with postoperative UTI: 18.8% with POUR vs 0.7% without (Pearson r = 0.369; P < .001). CONCLUSIONS POUR requiring bladder catheterization after CEA predisposes patients to postoperative UTI and is more common in older patients and those with a history of UTI. CEA patients lack inherent risk factors for POUR and would be a useful population for prospective studies involving POUR.

PC180. Superficial Femoral Artery Balloon Angioplasty Stent Implantation-Outcome Stratified by Type of Follow-up Evaluation: Arterial Duplex Imaging versus Ankle-Brachial Index Only

Results: Clinical case 2 describes a 48-year-old woman with a history of Takayasus arteritis, prior proximal descending thoracic aorta to infrarenal abdominal aortic bypass and bypass to the left renal artery for mid-aortic syndrome, and atrophic right kidney presented with severe hypertension, fluid overload, and hyperkalemia, and a creatinine of 5.8 mg/dL requiring urgent dialysis. She was anuric and dialysis dependent. Magnetic resonance angiography revealed occlusion of the left renal artery bypass which originated from the aortic bypass graft and collateral filling of the left kidney with differential areas of perfusion (Fig 2). She underwent redo aortic graft to left renal artery bypass 18 days after her initial presentation. Upon discharge, she was no longer dialysis dependent and her creatinine has normalized. Conclusions: Two patients presenting with dialysis dependent acute renal failure underwent delayed renal artery revascularization, greater than 14 days from their presentation. Complete renal recovery with return to baseline renal function was observed in these patients. In select patients, delayed renal artery revascularization (>48 hours of warm ischemic time) is controversial, but can be associated with complete renal recovery and freedom from dialysis.

Benefit of Arterial Duplex Ultrasound Stent Imaging After Superficial Femoral Artery Stent Implantation: Impact of Surveillance Method on Postprocedural Outcome

Objective: In-stent stenosis is a frequent complication of superficial femoral artery (SFA) endovascular intervention and can lead to stent occlusion or symptom recurrence. Arterial duplex ultrasound stent imaging (ADSI) can be used in the surveillance for recurrent stenosis; however, its uniform application is controversial. In this study, we aimed to determine, in patients undergoing SFA stent implantation (SI), whether surveillance with ADSI yielded a better outcome than in those with only anklebrachial index (ABI) follow-up. Methods: We performed a retrospective analysis of all patients undergoing SFA SI for occlusive disease at a tertiary care referral center between 2009 and 2016. The patients were divided into those with ADSI (ADSI group) and those with ABI follow-up only (ABI group). Life-table analysis comparing stent patency, major adverse limb event (MALE), limb salvage, and mortality between groups was performed. Results: There were 248 patients with SFA SI included, 160 in the ADSI group and 88 in the ABI group. Groups were homogeneous regarding clinical indication (claudication/critical limb ischemia, ADSI 39%/61% vs ABI 38%/62%; P 1⁄4 .982) and TransAtlantic Inter-Society Consensus classification (A/B/C/D for ADSI 17%/45%/16%/22% and ABI 21%/43%/16%/20%; P 1⁄4 .874). Primary patency (PP) was similar between groups at 12, 36, and 56 months (ADSI, 65%/43%/32%; ABI, 69%/34%/34%; P 1⁄4 .770), whereas ADSI patients showed an improved assisted PP (84%/68%/54%) vs ABI (76%/38%/38%; P 1⁄4 .008) and secondary patency (Fig 1). There was a greater freedom from MALE in the ADSI group (91%/76%/64%) vs the ABI group (79%/46%/46%; P < .001) at 12, 36, and 56 months of followup. ADSI patients were more likely to undergo an endovascular procedure as their initial post-SFA SI intervention (P 1⁄4 .001), whereas ABI patients were more likely to undergo an amputation (P < .001; Fig 2). Conclusions: In SFA SI, patients with ADSI follow-up demonstrate an advantage in assisted PP and secondary patency and are more likely to undergo an endovascular reintervention. These factors likely effected a

Contrast-induced nephropathy after peripheral vascular intervention: Long-term renal outcome and risk factors for progressive renal dysfunction

Objective Contrast‐induced nephropathy (CIN) is a frequently used quality outcome marker after peripheral vascular interventions (PVIs). Whereas the factors associated with CIN development have been well documented, the long‐term renal effects of CIN after PVI are unknown. This study was undertaken to investigate the long‐term (1‐year) renal consequences of CIN after PVI and to identify factors associated with renal function deterioration at 1‐year follow‐up. Methods From 2008 to 2015, patients who had PVI at our institution (who were part of a statewide Vascular Interventions Collaborative) were queried for those who developed CIN. CIN was defined by the Collaborative as an increase in serum creatinine concentration of at least 0.5 mg/dL within 30 days after intervention. Preprocedural dialysis patients or patients without postprocedural creatinine values were excluded. Preprocedural, postprocedural, and 1‐year serum creatinine values were abstracted and used to estimate glomerular filtration rate (GFR). &Dgr;GFR was defined as preprocedural GFR minus 1‐year GFR. Univariate and multivariate analyses for &Dgr;GFR were performed to determine factors associated with renal deterioration at 1 year. Results From 2008 to 2015, there were 1323 PVIs performed; 881 patients met the inclusion criteria. Of these, 57 (6.5%) developed CIN; 47% were male, and 51% had baseline chronic kidney disease. CIN resolved by discharge in 30 patients (53%). Using multivariate linear regression, male sex (P = .027) and congestive heart failure (P = .048) were associated with 1‐year GFR decline. Periprocedural variables related to 1‐year GFR decline included percentage increase in 30‐day postprocedural creatinine concentration (P = .025), whereas CIN resolution by discharge (mean, 13.1 days) was protective for renal function at 1 year (P = .02). A post hoc analysis was performed with 50 PVI patients (randomly selected) who did not develop CIN, comparing their late renal function with that of the CIN group stratified by the periprocedural 30‐day variables. Patients with CIN resolution at discharge had similar 1‐year renal outcomes to non‐CIN patients, whereas the CIN‐persistent (at discharge) patients had greater renal deterioration at 1 year compared with non‐CIN patients (P = .016). Conclusions Male sex and congestive heart failure are risk factors for further renal function decline in patients developing CIN after PVI. The magnitude and duration of increase in creatinine concentration (CIN persistence at discharge) correlated with late progressive renal dysfunction in CIN patients, suggesting that early‐resolving CIN is relatively benign.

RS04. Natural History of Progression of Carotid Artery Stenosis

neurologic complications. Propensity score analysis was performed to verify the role of EMB in CBT surgery. Results: The number of CBT patients and CBT operations rapidly increased in recent years. The population was composed of 132 patients (74 males and 58 females) with 142 CBTs resected. Tumor classification was Shamblin I in 29 tumors, Shamblin II in 61, and Shamblin III in 52. Of these, 97 tumors underwent EMB, and significantly decreased vascularization was achieved in 99.0%. Intraoperatively, rupture of the internal carotid artery occurred in 29patients (20.4%) andwas successfully reconstructed in 28 patients (96.4%) and ligated in one patient (3.6%). After surgery, a transient cranial deficitwas identified in 44patients (31%), and strokewas found in four patients (2.8%). During a mean follow-up of 60.7 months, seven patients (4.9%) were lost to follow-up, and a permanent nerve deficit was found in 18 (13.3%). Multivariate regression analysis revealed that the incidence of neurologic complications was associated with Shamblin group III (P1⁄4 .005 for in-hospital complication; P1⁄4 .001 for permanent neurologic complication) and high-lying tumors (P1⁄4 .047 for in-hospital complication; P 1⁄4 .101 for permanent neurologic complication). In comparison with the non-EMBgroup, the EMBgroupdidnot exhibit decreased rates of in-hospital neurologic complications (9 vs 15; P1⁄4 .151) or persistent neurologic complications (4 vs 6; P 1⁄4 .502) but had decreased operation times (100.0 minutesvs 183.0minutes;P< .001) andblood loss (65mLvs 100mL;P1⁄4 .039). Conclusions: Surgical resection of CBTs is the gold standard. The rate of neurologic complications is acceptable. Shamblin group III and highlying tumors were vulnerable to neurologic complications. EMB did not decrease the risks of neurologic complications, although it decreased operation times and blood loss.

IP231 Kidney Transplant Increases the Risk of Ipsilateral Critical Limb Ischemia

Proposal of a Multicentric-Based Score for Graft Patency in Below-knee Femoropopliteal Bypass With Heparin-Bonded ePTFE Graft in Patients With Critical Limb Ischemia Walter Dorigo, Gabriele Piffaretti, Raffaele Pulli, Paolo Ottavi, Patrizio Castelli, Carlo Pratesi. University of Florence, Florence, Italy; Insubria University, Varese, Italy; University of Bari, Bari, Italy; Terni Hospital, Terni, Italy