Site of service influence on stent use for hemodialysis access interventions.

OBJECTIVE: With rising health care spending in the United States, the Centers for Medicare and Medicaid Services (CMS) in recent years attempted to use reimbursement rates to influence use of less expensive care sites for covered patients, such as ambulatory surgery centers (ASCs) and office-based laboratories (OBLs), in lieu of hospital service sites. It has been suggested that cost savings have not been realized because of more procedures being performed by physicians with ownership interests in nonhospital facilities. CMS adopted massive reimbursement changes for 2019 OBL and ASC-based procedures, which reduced dialysis access angioplasty reimbursement in the ASC setting by 50%, whereas facility reimbursement for stenting increased by 33% above prior levels. The clinical utility of adjunctive stenting in treating dialysis access stenosis remains controversial and highly discretionary. As a vascular group performing such procedures in both a hospital and nonhospital facility in which we have equity interest, we reviewed our use of stents in dialysis access procedures both in the hospital and in the ASC/OBL to determine whether site of service affected stent use. METHODS: A retrospective review of a prospectively maintained database was performed from 2014 to 2018. All patients undergoing dialysis access angiography with angioplasty and adjunctive stent placement at our OBL (later ASC) and our primary hospital were included in the study. RESULTS: There were 961 angioplasty or stent procedures performed for dialysis accesses between the two sites, 564 (58.7%) in the hospital setting and 397 (41.3%) at the OBL/ASC. There was a significant difference in race and age between the two sites, with younger, minority patients more frequently being treated in the hospital and older, white patients more likely to be treated in the ambulatory setting; 153 (27.1%) underwent adjunctive stent placement in the hospital and 127 (32.0%) in the ambulatory setting (P = .09). CONCLUSIONS: Whereas financial incentives have not yet had an appreciable influence on stent use for dialysis access within previous reimbursement paradigms, the dramatic changes recently adopted by CMS may well alter this dynamic and could lead to substantially higher overall costs without proven clinical advantage. Interventionalists may be incentivized to add stents when performing balloon angioplasty in ASCs. With high failure and reintervention rates and increasingly expensive adjuncts (drug-coated balloons and stents, covered stents), the cost implications of attempts to incentivize interventionalists toward a specific type of procedure or site of care are substantial, and unintended negative consequences are likely to occur.

Lateral femoral bypass for prosthetic arterial graft infections in the groin.

OBJECTIVE: Prosthetic arterial graft infections (PAGIs) in the groin pose significant challenges in terms of revascularization options and risk of limb loss as well as associated morbidities. Although obturator canal bypass (OCB) has been suggested for revascularization of the extremity in these cases, moderate success rates and technical challenges have limited widespread use. Our study analyzed lateral femoral bypass (LFB) as an alternative approach for the treatment of groin PAGIs. METHODS: This is a retrospective review of a prospectively maintained database of patients who underwent LFB for groin PAGIs at a single center from 2000 to 2017. Patients' data including demographics, comorbidities, perioperative complications, graft patency, and need for reintervention were used. Patients were observed after LFB with duplex ultrasound surveillance in an accredited noninvasive vascular laboratory every 3 months during the first year, followed by every 6 months for the second year and yearly thereafter. After isolation of the infected wound with sterile dressings, remote proximal and distal arterial exposure incisions were made. LFBs were tunneled under the inguinal ligament and lateral to the infected wound from an uninvolved inflow artery or bypass graft to an uninvolved outflow vessel. RESULTS: A total of 19 LFBs were performed in 16 patients (mean age, 69 ± 12.6 years). Three LFBs were performed urgently for acute bleeding. Choice of conduit included 6 (31.6%) autogenous vein grafts, 10 (52.6%) cadaveric grafts, 2 (10.5%) rifampin-soaked Dacron grafts, and 1 (5.3%) polytetrafluoroethylene graft. Average follow-up was 33 months (range, 0-103 months). Major adverse events occurring within 30 days of the operation included one (5.3%) death and one (5.3%) graft excision for pseudoaneurysm. Primary patency and primary assisted patency at 12 and 24 months were 73% and 83%, respectively. One patient required an amputation 17 months after surgery after failure of repeated revascularization attempts. Overall limb salvage was 93.8% during this follow-up period. CONCLUSIONS: In this series, LFB for management of groin PAGIs demonstrated higher patency and limb salvage rates compared with previous reports of OCB. Diligent postoperative duplex ultrasound surveillance is critical to the achievement of limb salvage and maintenance of graft patency. These results suggest that LFB, which is technically less complex than OCB, should be considered the first choice for revascularization in select cases of PAGIs involving the groin.

Outcomes of Brachial Artery Access for Endovascular Interventions.

BACKGROUND: A percutaneous brachial artery (BA) approach is a suitable or even favorable alternative to femoral artery access when performing certain endovascular interventions. However, this approach may have a higher complication rate compared to femoral artery access. We analyzed our results using percutaneous BA approach for noncardiac endovascular interventions. METHODS: Between January 1, 2003 and December 31, 2017, BA access was used in 157 cases performed on 136 patients. The procedures included 102 (65%) therapeutic interventions and 55 (35%) diagnostic studies. The vessels studied or treated included lower extremity arteries (48), the aorta and iliac arteries (45), mesenteric arteries (45), failing arterial revascularizations (24), renal arteries (9), subclavian arteries (8), carotid arteries (2), and visceral aneurysms (2), or in conjunction with endovascular aneurysm repair (EVAR), fenestrated EVAR, or thoracic EVAR (8). More than 1 vessel was studied or treated in 34 cases. Sheath sizes included 5F in 38 (24%) cases, 6F in 93 (59%) cases, and 7F in 26 (17%) cases. Percutaneous puncture was utilized in 142 (90.4%) cases and planned surgical exposure with primary closure of the BA in 15 (9.6%) cases (10, 7F; 4, 6F; 1, 5F). Manual compression was used for hemostasis at the conclusion of all percutaneous cases. RESULTS: There were 2 (1.3%; 2/157 cases) deaths in the perioperative period, one due to myocardial infarction and the other from mesenteric ischemia. Access site complications occurred in 10.6% (15/142) of percutaneous cases, which required open surgical repair for bleeding (8) and BA thrombosis (7). There was an increased risk of complications with increasing sheath size in the percutaneous approach: 5.4% (2/37), 12.4% (11/89), and 12.5% (2/16) for 5F, 6F, and 7F sheaths, respectively (P = 0.49). None of the 15 patients who underwent surgical treatment suffered long-term vascular or neuropathic complications. CONCLUSIONS: In our experience, percutaneous BA access was associated with a 10% complication rate with an increased risk of complications associated with increasing sheath size. There was approximately the same incidence of bleeding as thrombosis. For patients who require 6 or 7F sheaths via a BA approach, we recommend more liberal use of open surgical exposure and primary BA repair.

Celiac artery stent placement for coronary ischemia.

INTRODUCTION: The use of endovascular technology for mesenteric interventions has become an increasingly accepted treatment modality. We present an unusual case of celiac artery stent placement for coronary ischemia. CASE DESCRIPTION: A 66-year-old male with a history most notable for coronary artery disease and coronary artery bypass grafting (CABG) x 3 utilizing left internal mammary artery to left anterior descending, radial artery to first diagonal and his right gastroepiploic artery (GEA) to posterior descending artery presented with chest pain. His work-up included a cardiac catheterization that revealed a 90% stenosis at the origin of the celiac axis. A subsequent computerized tomography angiogram confirmed this and noted moderate stenosis of his superior mesenteric artery (SMA) as well as severe inferior mesenteric artery (IMA) stenosis. The patient was taken for mesenteric angiography by vascular surgery at which time he underwent balloon-expandable stent placement in the celiac axis. The patient tolerated this procedure well and was noted to have an improvement in his symptoms postoperatively. DISCUSSION: Use of arterial conduits for CABG have proven to be superior to vein. Long-term viability of the GEA as a conduit is dependent in part on the patency of mesenteric circulation. Our findings demonstrate a viable endovascular treatment option for angina pectoris secondary to mesenteric stenosis in this unique patient population.

Duplex ultrasound diagnosis of failing stent grafts placed for occlusive disease.

OBJECTIVE: We previously showed that duplex ultrasound (DU) imaging is beneficial in the diagnosis of failing vein and prosthetic grafts performed for arterial occlusive disease. The purpose of this study was to evaluate whether DU imaging can reliably diagnose failing stent grafts (ie, covered stents) placed for arterial occlusive disease. METHODS: Between July 1, 2005, and June 30, 2013, we placed 142 stent grafts in 92 arterial segments (1.5 stent grafts/stenotic artery) for lower extremity occlusive disease in patients who also underwent at least one DU surveillance study documenting a patent stent graft. Stent grafts were placed in 29 iliac and 52 femoropopliteal arteries and in 11 failing infrainguinal bypass grafts. Stent grafts used were Viabahn (W. L. Gore and Associates Inc, Flagstaff, Ariz) in 116 (82%), Wallgraft (Boston Scientific, Natick, Mass) in 23 (16%), Fluency (C. R. Bard Inc, Tempe, Ariz) in 2 (1%), and iCast (Atrium, Hudson, NH) in 1 (1%). Mean follow-up was 16 months (range, 1 week-86 months). Postoperative DU surveillance was performed in our Intersocietal Accreditation Commission accredited noninvasive vascular laboratory at 1 week, then every 3 months the first year, and every 6 months thereafter. DU measured peak systolic velocities (PSVs) and velocity ratio of adjacent PSVs (Vr) every 5 cm within the stent graft and adjacent arteries. RESULTS: We retrospectively classified the following factors as "abnormal DU findings:" focal PSVs >300 cm/s, uniform PSVs <50 cm/s throughout the graft, and a Vr >3.0. Fifteen of 20 patients with one or more of these abnormal DU findings underwent prophylactic intervention (n = 8) or occluded without intervention (n = 7), whereas only two of 72 with normal DU findings occluded (P = .0001). Excluding the eight patients who underwent prophylactic intervention, seven of 12 patients with abnormal DU findings occluded without intervention vs two of 72 with normal DU findings (P = .0001). CONCLUSIONS: These findings suggest that follow-up DU surveillance can predict failure of stent grafts placed for lower extremity occlusive disease. Focal PSVs >300 cm/s, Vr >3.0, and most importantly, uniform PSVs <50 cm/s throughout the stent graft were statistically reliable markers for predicting stent graft thrombosis.

Completion Arteriogram Following Carotid Endarterectomy Yields Lower Perioperative Stroke Rate.

Introduction: Completion imaging following carotid endarterectomy (CEA) remains controversial. We present our experience performing routine completion arteriography (CA). Methods: A retrospective review of our prospectively maintained institutional database was performed for patients undergoing isolated CEA. Results: 1439 isolated CEAs with CA were performed on 1297 patients. CEA was for asymptomatic lesions in 70% (1003) of cases. There were no complications related to arteriography. An abnormal arteriogram documented significant abnormalities in the internal carotid artery (ICA) and prompted revision in 1.7% (24/1439) of cases: 20 unsatisfactory distal endpoints of the endarterectomy (12 residual stenoses, 7 intimal flaps, and 1 dissection), 3 kinks or stenoses within the body of the patch, and 1 thrombus. Of the 20 distal endpoint lesions, stent deployment was used in 17 cases and patch revision in 3 cases. The other 4 cases were treated by patch angioplasty (3) or thrombectomy (1). None suffered a perioperative stroke. The overall 30-day stroke, death, and combined stroke/death rate for the 1439 patients in our series was 1.5% (22), .5% (7), and 1.9% (27), respectively. The combined stroke/death rate for asymptomatic lesions was 1.1% (11/1003) and for symptomatic lesions was 2.5% (11/436). Of the 22 strokes in the entire series (all with normal CA), 15 were non-hemorrhagic strokes ipsilateral to the CEA; 14 were confirmed to have widely patent endarterectomy sites by CT-A (13) or re-exploration and repeat arteriography (1). The occluded site was re-explored and underwent thrombectomy, but no technical problems were identified. The remaining strokes were hemorrhagic (4 reperfusion syndrome and 1 surgical site bleeding) or contralateral to the CEA (2). Conclusion: Although not all patients in this series who underwent intraoperative revision due to abnormal CA might have suffered a stroke, performing this simple and safe study may have halved our overall perioperative stroke rate from 3.2% to 1.5%.

Comparison of inflammatory response during on-pump and off-pump coronary artery bypass surgery.

PURPOSE: On-pump coronary artery bypass graft (CABG) surgery has been traditionally associated with a higher magnitude of inflammatory response than off-pump CABG. However with the development of polymer-coated biocompatible extracorporeal circuits, we wanted to see if cardiopulmonary bypass still played an important role in triggering this inflammatory response. METHODS: In this prospective observational study, 33 patients undergoing CABG surgeries (25 on-pump and 8 off-pump patients) were studied. Serial plasma cytokine (TNF IL-6, IL-10) and procalcitonin concentrations were measured at different time-points during and after the surgery. Demographic and baseline clinical data, intra-operative management details and post-operative complications were also collected from the patients' charts. RESULTS: Plasma levels of all 4 mediators increased during surgery and returned towards normal postoperatively. There were no differences between groups for any mediator at any time-point. CONCLUSIONS: We conclude that with the use of recent polymer-coated biocompatible extracorporeal circuits, the inflammatory response triggered by on-pump CABG becomes very similar in magnitude and pattern to that triggered by off-pump CABG. Thus, the surgical procedure contributes to most of the inflammatory response, with the extra-corporeal circuit having minimal to no effect on this response.

Preload responsiveness is associated with increased interleukin-6 and lower organ yield from brain-dead donors.

OBJECTIVE: Brain death induces dramatic changes in hemodynamics. Ischemic injury and inflammation resulting from inadequate resuscitation might influence organ yield for transplantation. Using functional hemodynamic monitoring in brain-dead organ donors, we test the hypothesis that donor preload (fluid) responsiveness is associated with increased inflammatory response and lower organ yield for transplantation. DESIGN: Prospective, observational, pilot study. SETTING: A large intensive care unit of a university hospital in the United States. PATIENTS: Twenty-one brain-dead organ donors between July 2006 and April 2007. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Following declaration of brain death, we collected data on donor demographics, mechanism of brain death, and number of organs procured and transplanted. Functional hemodynamics were monitored using pulse contour analysis technique. Plasma tumor necrosis factor, interleukin-6, and interleukin-10 concentrations were measured at study enrollment, after 4 hrs, and immediately before organ procurement for transplantation. Preload responsiveness (pulse pressure variation >13%) was observed in 48% of donors (mean +/- sd pulse pressure variation, 19.2% +/- 4.8%). Plasma interleukin-6 and tumor necrosis factor concentrations at study enrollment were greater in preload responsive donors: mean concentrations of interleukin-6 in preload responsive vs. unresponsive donors were 5420 +/- 9102 vs. 378 +/- 631 pg/mL (p = .009), and mean concentrations of tumor necrosis factor were 60.5 +/- 103.6 vs. 15.7 +/- 10.1 pg/mL (p = .048). Preload responsive compared with unresponsive donors had significantly increased interleukin-6 (p = .013) and tumor necrosis factor (p = .044) concentrations over time. Fewer organs were transplanted from preload responsive donors: mean organs transplanted from preload responsive vs. unresponsive donors were 1.8 +/- 0.9 vs. 3.7 +/- 2.5 (p = .034). In multivariable regression, older donor age (p = .028) and increased plasma interleukin-6 concentration (p = .035) were significantly associated with lower number of organs transplanted. CONCLUSIONS: Preload responsiveness is common in brain-dead organ donors and is associated with higher inflammatory response and lower organ yield. A controlled trial of preload optimization is warranted in brain-dead donors.

Giant renal vein aneurysm.

A 37-year-old asymptomatic man presented with incidentally identified intra-abdominal venous aneurysms. Workup, which included venography, demonstrated an absent segment of the inferior vena cava between the inferior right and superior left renal vein, resulting in a 4.4-cm right renal vein aneurysm, dilated common iliac veins, and left external iliac vein aneurysm. Collateralization was robust. Given the limited natural history data and complexities of open reconstruction, we opted to observe this asymptomatic patient with serial imaging, which demonstrated no interval change. We present our case and a review of the literature pertaining to intra-abdominal venous aneurysms.

Persistent Hypoglossal Artery: Challenges Associated With Carotid Revascularization.

Anomalous connections between the anterior and posterior cranial circulation are rare embryologic entities. A persistent hypoglossal artery has a reported incidence of 0.03% to 0.09% and has been linked to intracranial aneurysms, atherosclerosis, and posterior circulation ischemia. Identification of this anomaly is essential prior to carotid artery revascularization given the technical challenges and added risks with intervention. We report a case of an 80-year-old female with progression of carotid stenosis in the setting of a persistent hypoglossal artery. We provide a review of the literature and discuss the technical challenges of carotid revascularization in this patient.

Increased plasma interleukin-6 in donors is associated with lower recipient hospital-free survival after cadaveric organ transplantation.

OBJECTIVES: Brain death induces a massive inflammatory response. However, the influence of this inflammatory response on organ procurement, transplantation, and recipient outcome is unknown. We describe the inflammatory response characteristics in brain-dead organ donors and examine associations with organ transplantation and recipient survival. We test the hypothesis that increased inflammatory response is associated with fewer organs transplanted and decreased recipient survival. DESIGN: Prospective, observational, cohort study. SETTING: Two large intensive care units of tertiary care university hospitals in the United States. PATIENTS: We recruited 30 consecutive brain-dead organ donors and 78 recipients between April 11, 2004, and November 23, 2004; recipients were followed through May 2005. Following declaration of brain death, we collected data on donor demographics, mechanism of brain death, number of organs procured and transplanted, and recipient characteristics. Plasma cytokines (tumor necrosis factor, interleukin-6, interleukin-10) were measured in donors at baseline following study enrollment, every hour for the first 4 hrs, and immediately before organ procurement for transplantation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We examined the relationships among clinical characteristics, demographics, and cytokine response in donors and their influence on organ procurement and transplantation using multivariable regression and recipient's 6-month hospital-free survival using a Cox proportional hazards regression. One hundred-eighteen organs were procured from 30 donors, and 91 (77%) were transplanted (mean of three organs transplanted per donor). All cytokines were increased following brain death. Older age in donors was significantly associated with lower number of organs transplanted (p < .001). Higher plasma interleukin-6 concentrations in donors before organ procurement was significantly associated with lower 6-month hospital-free survival in recipients (hazard ratio 1.77; 95% confidence interval, 1.17-2.69, p < .007). CONCLUSIONS: Among brain-dead organ donors, older age donors contribute fewer organs for transplantation, and increased donor interleukin-6 level before organ procurement is associated with lower recipient six-month hospital-free survival.

Use of a small intestine submucosa extracellular matrix patch in repeated carotid endarterectomy.

Various patches have been described in the literature for patients undergoing carotid endarterectomy. In the present report, the authors present the case of a 71-year-old woman who had bilateral carotid endarterectomies 17 years earlier and greater than 80% restenosis of the right internal carotid artery. The patient underwent a repeated right carotid endarterectomy using a small intestine submucosa extracellular matrix patch for closure of the arteriotomy. Given the unique biologic properties of the small intestine submucosa patch and the technical advantages associated with its use for patch angioplasty, further studies to define its efficacy are warranted.