Windsor Ting

Endovascular treatment of visceral artery aneurysms.

Visceral artery aneurysms, although uncommon, can present with life-threatening hemorrhage. The increasing use of imaging studies has allowed for earlier identification and intervention of these aneurysms, thus avoiding the high morbidity and mortality associated with rupture. The treatment options for visceral artery aneurysms range from conventional open surgical repair to minimally invasive techniques using covered stents or embolization materials. Anatomic features and patient selection determine which treatment option would result in the most durable treatment and outcome. This article reviews our experience with the endovascular treatment of visceral artery aneurysms.

The effect of a hospitalist comanagement service on vascular surgery inpatients

OBJECTIVE Vascular surgery patients have increased medical comorbidities that amplify the complexity of their care. We assessed the effect of a hospitalist comanagement service on inpatient vascular surgery outcomes. METHODS We divided 1059 patients into two cohorts for comparison: 515 between January 2012 and December 2012, before the implementation of a hospitalist comanagement service, and 544 between January 2013 and October 2013, after the initiation of a hospitalist comanagement service. Nine vascular surgeons and 10 hospitalists participated in the hospitalist comanagement service. End points measured were in-hospital mortality, length of stay (LOS), 30-day readmission rates, visual analog scale pain scores (0-10), inpatient adult safety assessments using the Agency for Healthcare Research and Quality (AHRQ) Patient Safety Indicators, and resident perceptions assessed by survey. RESULTS The in-hospital mortality rate decreased from 1.75% to 0.37% after the implementation of the hospitalist comanagement service (P = .016), with a decrease in the observed-to-expected ratio from 0.89 to 0.22. The risk-adjusted in-hospital mortality decreased from 1.56% to 0.0008% (P = .003). Mean LOS was lower in the base period, at 5.1 days vs 5.5 days (P < .001), with an observed-to-expected ratio of 0.83 and 0.78, respectively. The risk-adjusted LOS increased from 4.2 days to 4.3 days (P < .001). The overall 30-day readmission rate was unchanged, at 23.1% compared with 22.8% (P = .6). The related 30-day readmission rate was also similar, at 11.5% compared with 11.4% (P = .5). Patients reporting no pain during hospitalization increased from 72.8% before the hospitalist comanagement service to 77.8% after (P = .04). Reports of moderate pain decreased from 14% to 9.6% (P = .016). Mild and severe pain scores were similar between the two groups. Adult safety measured by AHRQ demonstrated a decrease from three to zero patients in the number of deaths among surgical patients with treatable complications (P = .04). Most house staff reported that the comanagement program had a positive effect on patient care and education. CONCLUSIONS The hospitalist comanagement service has resulted in a significant decrease in in-hospital mortality rates, patient safety, as measured by AHRQ, and improved pain scores. Resident surveys demonstrated perceived improvement in patient care and education. Continued observation will be necessary to assess the long-term effect of the hospitalist comanagement service on quality metrics.

Preoperative inflammatory status as a predictor of primary patency after femoropopliteal stent implantation

Objective: The purpose of this study was to evaluate the impact of preoperative inflammatory status, as determined by complete blood count test parameters, on 12‐ and 24‐month patency of femoropopliteal stenting for peripheral arterial disease. Methods: We retrospectively analyzed baseline clinical and angiographic data among 138 patients (median age, 73 years; 46% female) from 2005 to 2014 at our institution with preoperative complete blood count test values and information of patency for at least 12 months after first‐time femoropopliteal stenting. Patients were stratified into tertiles on the basis of preoperative blood counts to evaluate associations with in‐stent restenosis (ISR) leading to loss of primary patency, defined by a Doppler velocity ratio ≥2.5:1, computed tomography angiography demonstrating ≥50% luminal narrowing within the stent, or reintervention. Results: Univariate analysis determined that the 81 patients (59%) who experienced ISR within 12 months had significantly higher preoperative white blood cell (WBC), platelet, neutrophil, and lymphocyte counts than the 57 patients (41%) whose stents remained patent for longer than 12 months (8.7 vs 6.7 [P < .001], 246 vs 184 [P < .001], 5.7 vs 4.7 [P = .001], and 1.8 vs 1.2 [P = .004], respectively). Compared with patients in the lower WBC tertile (n = 45) who had a median patency of 19.4 months, those in the upper WBC tertile (n = 44) had a median patency of only 7.0 months and a 3.3‐fold increased risk for ISR after adjusting for age, sex, lesion type, TransAtlantic Inter‐Society Consensus II score, tibial vessel runoff, antiplatelet therapy, presence of diabetes, critical limb ischemia, adjunct procedures, hyperlipidemia, and end‐stage renal disease in multivariate analysis (P < .001). Compared with patients in the lower platelet tertile (n = 45) who had a median patency of 16.9 months, those in the upper platelet tertile (n = 47) had a median patency of 7.1 months and a 2.7‐fold increased adjusted risk (P = .001). Compared with patients in the lower neutrophil tertile (n = 33) who had a median patency of 14.3 months, those in the upper neutrophil tertile (n = 33) had a median patency of 6.2 months and a 3.2‐fold increased adjusted risk (P = .001). After adjusting for covariates, patients divided into tertiles by lymphocyte counts exhibited no significant differences for ISR. Conclusions: Routine preoperative tests that determine baseline inflammatory status may provide strong clinical utility in assessing potential risk stratification of patients for ISR after femoropopliteal stenting. Circulating WBCs, platelets, and neutrophils may be important inflammatory mediators of ISR.

Magnetic Resonance Imaging in Proximal Venous Outflow Obstruction

BACKGROUND Proximal venous outflow obstruction (PVOO) in the abdomen and pelvis is increasingly recognized as an important contributor to venous disease of the lower extremity. There are currently no guidelines regarding a noninvasive screening tool for PVOO, although magnetic resonance venography (MRV) is commonly used in many practices. The objective of this study was to determine the value and utility of MRV in diagnosis and screening for PVOO. METHODS This retrospective study consisted of 46 consecutive patients, all of whom presented with signs and/or symptoms of PVOO and were evaluated with MRV followed by intravascular ultrasound (IVUS) and venography. Of these 46 patients suspected to have PVOO based on clinical evaluation, 24 patients had PVOO confirmed with IVUS and venography and PVOO was not observed on IVUS and venography in the remaining 22 patients. The MRV of these 46 patients was retrospectively reviewed in a blinded fashion and then correlated with IVUS and venography by 1 vascular surgeon. A scoring system was developed to define the types of radiography findings that were observed: normal, suspicious, and abnormal. RESULTS When compared with IVUS and multiplane venography, the interpretation of MRV had a sensitivity of 100% and a specificity of 22.7%. The positive predictive value of MRV was 58.5%, and the negative predictive value was 100%. CONCLUSIONS The high sensitivity (100%) and low specificity (22.7%) of MRV suggest that it can be a screening tool at best, used only to rule out PVOO; it cannot be used to confirm PVOO, given its a 41.5% false positive rate. Thus, the development of a different, noninvasive diagnostic test that can more accurately assess patients with suspected PVOO during the initial evaluation of their lower-extremity venous disease should be explored.

A Review of Superficial Femoral Artery Angioplasty and Stenting

Introduction: Peripheral arterial disease (PAD) of the superficial femoral artery (SFA) is the most common cause of intermittent claudication. Several endovascular treatment options exist; the most frequent are angioplasty or angioplasty with stent placement. The aim of this review is to clarify the role of angioplasty alone vs. angioplasty with stent placement. Methods: A literature review was conducted reviewing the topic of SFA angioplasty and SFA angioplasty with stenting. Three notable randomized trials were included in addition to other available studies on the topic. Results: When a residual stenosis or flow limiting dissection is visualized, stenting is clearly necessary. Current literature favors the use angioplasty for short (~4 cm) SFA stenoses or occlusions due to comparable patency and results. Primary stenting using Nitinol stents may be a superior initial treatment for intermediate (6-8 cm) and long (>10 cm) length lesions. In these intermediate and long length lesions, the use of stents appears to reduce the restenosis rates and improves patency. Conclusion: Angioplasty works best for short SFA stenoses or occlusions. However, angioplasty with stenting using is likely superior initial treatment for intermediate and long length lesions.

Bilateral May-Thurner syndrome refractory to iliac aneurysm repair

Venous complications of iliac artery aneurysms are rare. We report the case of bilateral iliac aneurysms that resulted in iliac vein outflow obstruction despite endovascular aneurysm repair. In our patient, bilateral iliac vein stenting resulted in symptom resolution.

Outcomes of using endovascular aneurysm repair with active fixation in complex aneurysm morphology

Objective The ideal treatment option for patients with complex aneurysm morphology remains highly debated. The aim of this study was to investigate the impact of endovascular aneurysm repair (EVAR) with active fixation on outcomes in patients with complex aneurysm morphology. Methods There were 340 consecutive patients who underwent EVAR using active fixation devices, 234 with active infrarenal fixation (AIF; Gore Excluder; W. L. Gore & Associates, Flagstaff, Ariz) and 106 with active suprarenal fixation (ASF; 85 Medtronic Endurant [Medtronic, Santa Rosa, Calif] and 21 Cook Zenith [Cook Medical, Bloomington, Ind]). Demographics, comorbidities, anatomic features, and outcomes were analyzed for patients receiving devices with active fixation. Outcomes of using active fixation in necks with <15‐mm neck lengths, >60‐degree infrarenal neck angle (&bgr;), >30‐mm infrarenal neck diameter, severe aortic neck calcification or thrombus, and nonstraight neck morphology were evaluated. Results Of the 340 patients, 106 (78 men; mean age, 74.5 ± 9.3 years at the time of surgery) received implants with ASF and 234 (191 men; mean age, 74.6 ± 8.9 years at the time of surgery) received implants with AIF. In comparing AIF and ASF devices, patients in the suprarenal fixation group had significantly shorter follow‐up time (25 ± 17 months vs 44.3 ± 32 months; P < .0001). Patients in the ASF group had shorter aortic neck lengths (25.5 ± 15.1 mm vs 28.6 ± 14.9 mm; P = NS) and significantly larger infrarenal neck diameters (25.9 ± 6.3 mm vs 23.4 ± 3.2 mm; P < .0001) and aneurysm diameters (59.9 ± 11.6 mm v. 55.9 ± 10.0 mm; P = .002). Outcomes were similar between groups, with no significant differences in reintervention, proximal endoleak, sac growth, abdominal aortic aneurysm‐related death, or rupture. Of the complex anatomic neck features investigated, neck diameter >30 mm and nonstraight neck morphology had the highest rates of reintervention in ASF devices. Conclusions In cases of hostile infrarenal neck morphology, ASF appears to be used more frequently. Our data suggest that ASF may be useful for certain patients but may be unfavorable for others, such as those with wide necks or several difficult neck features. Nevertheless, further research is needed to evaluate more optimal treatment options, such as fenestrated EVAR, branched EVAR, and endovascular adjuncts such as EndoAnchors (Aptus Endosystems, Sunnyvale, Calif), in dealing with high‐risk anatomic characteristics that may not be optimally managed with standard EVAR devices with active fixation.

Secondary Interventions After Iliac Vein Stenting for Chronic Proximal Venous Outflow Obstruction

Background: Iliac stent placement is an increasingly common procedure in the treatment of chronic proximal venous outflow obstruction (PVOO), but secondary interventions after vein stent placement remain poorly characterized. Our goals were to identify the incidence, indications, operative findings, and outcomes of secondary interventions after the primary iliac vein stent procedure in a single institution. Methods: We retrospectively reviewed the clinical history of 490 patients (42.41% male; mean age, 60.77 years [range, 18-92 years]; 93.28% follow-up with a mean follow-up of 308.59 days) who underwent iliac stent placement (Wallstent; Boston Scientific, Marlborough, Mass) for PVOO between October 2013 and June 2016. We specifically evaluated the clinical presentation, intraoperative findings, and outcomes among those patients who required a secondary intervention after an initial iliac vein stent procedure. Results: Secondary interventions after an initial stent placement were identified in 50 of 490 patients (10.2%; mean age, 61.54 years [range, 19-92 years]; 58% female [n 1⁄4 29]). Among these 50 patients, 56% (n 1⁄4 28) of secondary interventions were due to recurrence of symptoms after the initial stent surgery, 24% (n 1⁄4 12) were due to the development of new symptoms, and 20% (n 1⁄4 10) were due to persistence of symptoms. Intraoperative findings during the secondary intervention included migration of the stent (8% [n 1⁄4 4]), acute deep venous thrombosis/thrombosis (12% [n 1⁄4 6]), an additional lesion (ie, stenosis in a native iliac vein proximal or distal to the original lesion; 50% [n 1⁄4 25]), stenosis within the stent (stent stenosis without finding of thrombus or isolated, focal intrastent thrombosis; 16% [n 1⁄4 8]), impairment of flow of the contralateral vessel from the previous stent (12% [n 1⁄4 6]), and no finding (2% [n 1⁄4 1]). The types of secondary interventions were placement of a new stent (80% [n 1⁄4 40]), isolated balloon angioplasty alone (6% [n 1⁄4 3]), and catheter PMT (14% [n 1⁄4 7]). Significant symptomatic improvement was observed after the secondary intervention in 90% of patients (n 1⁄4 45); 2% (n 1⁄4 1) of patients experienced only a transient improvement, and 8% of patients (n 1⁄4 4) reported no improvement in their symptoms. Conclusions: This study establishes a secondary intervention rate of 10% after iliac vein stent placement for chronic PVOO, identifies discrete and definable intraoperative findings as targets for quality improvement, and indicates that secondary interventions after vein stent placement are associated with a good outcome.

PC138 Not All Vascular Surgery Readmissions Are Created Equal

Objectives: We investigated the risk factors associated with and causes of readmission of patients following an inpatient vascular surgery stay. Methods: A total of 1000 randomly selected patients who were admitted to the vascular surgery inpatient service between 2011 and 2014 were retrospectively identified; of these, 28 patients were excluded due to missing data points. Readmissions were measured both 30 days and 1 year after discharge from the initial hospital stay. The readmissions were characterized as planned/unplanned and related/unrelated. Planned readmissions were defined as readmissions scheduled at the time of the initial admission. Related readmissions were defined as readmissions clinically related to the initial admission. Predictors for readmission were analyzed using c tests and t-tests. Differences in types of readmission were analyzed using binomial tests and c goodness of fit tests. Results: The overall all-cause 30-day readmission rate was 23.3%, and the overall all-cause 1-year readmission rate was 53.8%. Compared to nonreadmitted patients, readmitted patients were more likely to be diabetic (69%), hypertensive (92%), hyperlipidemic (66%), former or active smokers (62%), and associated with other cardiovascular comorbidities (87%; P < .01, Table I). There were no differences in age or sex between readmitted and nonreadmitted patients. Of the 30-day readmissions, related/unplanned readmissions were the most common (P < .001) and constituted 36.7% of all 30-day readmissions (Table II). Of the 1-year readmissions, unrelated/unplanned readmissions occurred most frequently (38.4%; P < .001), although related/unplanned readmissions also contributed significantly, contributing to 25.8% of all 1-year readmissions (Table II). Major causes of related/unplanned readmissions included surgical site infection, healing problems, and failure of surgery. Other top causes for readmissions included amputation, wound débridement, and angioplasty/stenting for related/planned readmissions; peripheral intervention of alternate vascular bed for unrelated/planned readmissions; and exacerbation of an acute medical comorbidity, acute infection, or acute traumatic injury for unrelated/unplanned readmissions. Conclusions: Theoretically, related/unplanned readmissions are the most preventable type. Identifying the causes of these readmissions may allow us to reduce overall readmission rates. In our cohort, between 2011 and 2014, a total of 226 patients were readmitted within 30 days of their inpatient vascular surgery stay. If the 83 (36.7%) related/unplanned readmissions could have been prevented, the overall 30-day readmission rate could have been reduced from 23.3% to as low as 14.7%.