Fenestrated repair improves perioperative outcomes but lacks a hospital volume association for complex abdominal aortic aneurysms.

BACKGROUND: Complex abdominal aortic aneurysms (AAAs) have traditionally been treated with an open surgical repair (OSR). During the past decade, fenestrated endovascular aneurysm repair (FEVAR) has emerged as a viable option. Hospital procedural volume to outcome relationship for OSR of complex AAAs has been well established, but the impact of procedural volume on FEVAR outcomes remains undefined. This study investigated the outcomes of OSR and FEVAR for the treatment of complex AAAs and examined the hospital volume-outcome relationship for these procedures. METHODS: A retrospective review of a statewide vascular surgery registry was queried for all patients between 2012 and 2018 who underwent elective repair of a juxtarenal/pararenal AAA with FEVAR or OSR. The primary outcomes were 30-day mortality, myocardial infarction, and new dialysis. Secondary end points included postoperative pneumonia, renal dysfunction (creatine concentration increase of >2 mg/dL from preoperative baseline), major bleeding, early procedural complications, length of stay, and need for reintervention. To evaluate procedural volume-outcomes relationship, hospitals were stratified into low- and high-volume aortic centers based on a FEVAR annual procedural volume. To account for baseline differences, we calculated propensity scores and employed inverse probability of treatment weighting in comparing outcomes between treatment groups. RESULTS: A total of 589 patients underwent FEVAR (n = 186) or OSR (n = 403) for a complex AAA. After adjustment, OSR was associated with higher rates of 30-day mortality (10.7% vs 2.9%; P < .001) and need for dialysis (11.3% vs 1.8; P < .001). Postoperative pneumonia (6.8% vs 0.3%; P < .001) and need for transfusion (39.4% vs 10.4%; P < .001) were also significantly higher in the OSR cohort. The median length of stay for OSR and FEVAR was 9 days and 3 days, respectively. For those who underwent FEVAR, endoleaks were present in 12.1% of patients at 30 days and 6.1% of patients at 1 year, with the majority being type II. With a median follow-up period of 331 days (229-378 days), 1% of FEVAR patients required a secondary procedure, and there were no FEVAR conversions to an open aortic repair. Hospitals were divided into low- and high-volume aortic centers based on their annual FEVAR volume of complex AAAs. After adjustment, hospital FEVAR procedural volume was not associated with 30-day mortality or myocardial infarction. CONCLUSIONS: FEVAR was associated with lower perioperative morbidity and mortality compared with OSR for the management of complex AAAs. Procedural FEVAR volume outcome analysis suggests limited differences in 30-day morbidity, although long-term durability warrants further research.

Ambulatory venous pressure, air plethysmography, and the role of calf venous pump in chronic venous disease.

BACKGROUND: Ambulatory venous pressure (AMVP) records pressure dynamics with calf exercise. Air plethysmography (APG) measures related volume detail. APG has been suggested as a noninvasive surrogate for AMVP. We examine the correlations between APG and AMVP parameters and the role of "calf pump failure" in chronic venous disease (CVD). METHODS: A total of 8456 limbs in 4610 patients investigated for CVD during a 20-year period were analyzed. APG and AMVP data were available in 4599 limbs for calculation of Pearson correlation coefficient; 1347 of these limbs had significant iliac vein stenosis, proven by intravascular ultrasound. Venn diagrams are used to explore overlapping incidence of APG and AMVP abnormalities. RESULTS: APG calf volume and reflux (venous volume, venous filling index) showed progressively significant deterioration with advancing Clinical, Etiology, Anatomy, and Pathophysiology (CEAP) clinical class, anatomic extent of reflux (superficial, deep, perforator), and reflux severity (axial reflux, segmental score). Notably, calf ejection volume increased in a nearly linear fashion (R = 0.71) to venous volume such that residual volume fraction (RVF) remained normal even in the worst of these categories. AMVP too progressively deteriorated with clinical disease and reflux severity. Venous filling time was the key parameter as the pressure drop alone was abnormal in only 4% of the limbs analyzed. There was no correlation between RVF and AMVP (R = 0.22) or between AMVP and many other APG parameters. Venn distribution showed only minor overlap (30%) between AMVP and key APG abnormalities overall, but the overlap increases from 40% to 70% in advanced clinical and reflux categories. AMVP was rarely abnormal (7%) when APG was normal. Median AMVP was normal in calf pump failure categories, however defined (subnormal ejection fraction, RVF, or both). Median AMVP is normal in venous obstruction without reflux, while AMVP abnormalities are associated three to seven times more with reflux than with obstruction. CONCLUSIONS: APG (venous filling index) is a useful index of reflux. Calf pump ejection is a powerful and plastic compensatory mechanism, and calf pump failure is rare. Ambulatory venous hypertension is dominantly associated with reflux and less with obstruction. AMVP too worsens with clinical and reflux severity categories. However, there is little correlation between APG and AMVP parameters as APG measures volume and AMVP measures pressure, each in its own domain, and the volume-pressure curve is nonlinear. AMVP may be omitted in routine clinical testing if APG is normal, as the yield (7%) will be very low. AMVP reflects venous hypertension, the end stage in CVD. AMVP should be used to identify such cases when APG is abnormal.

Open Mesenteric Interventions Are Equally Safe as Endovascular Interventions and Offer Better Midterm Patency for Chronic Mesenteric Ischemia.

BACKGROUND: Endovascular (EV) techniques are being advocated as the preferred method for mesenteric interventions because of their safety profile. However, midterm and long-term results are thought to be inferior to open interventions. We sought to compare our institutional experience with treatment of acute and chronic mesenteric ischemia (AMI and CMI, respectively) using EV and open techniques. METHODS: The medical records of open and EV mesenteric procedures performed at a single center were queried from 2002 to 2012. Demographic, perioperative, and follow-up data were extracted and analyzed. RESULTS: Thirty-eight patients underwent EV mesenteric interventions, whereas 77 patients underwent open revascularization. The demographic and perioperative characteristics for patients were similar. Most EV procedures (89.2%) comprised stenting, whereas open procedures included 25 (32.1%) antegrade bypasses, 38 (48.7%) retrograde bypasses, 8 (10.3%) thromboembolectomies, and 7 (9%) transaortic endarterectomies. Postoperative complications, overall 30-day morbidity and mortality were not significantly different in the open and EV groups for AMI or CMI. Thirty-day mortality in AMI (n = 34) was 38.2% (EV: 45.5% vs. open: 34.8%; P = nonsignificant). There was no mortality in either group for CMI patients. Mean follow-up was much longer for the open procedures (34.9 vs. 12.7 months, P = 0.004). Primary and secondary patency rates were better for open revascularization for CMI patients. CONCLUSIONS: Open revascularizations are equally safe as EV interventions for AMI and CMI. Patency of open revascularization for CMI is better than EV procedures at midterm follow-up.

Evolution in the Management of Aberrant Subclavian Arteries and Related Kommerell Diverticulum.

BACKGROUND: Various options have been described to treat aberrant subclavian arteries and associated Kommerell diverticulum. We describe our experience with the management of this entity over a 15-year period. METHODS: Twenty-two patients underwent repair of aberrant subclavian arteries and associated Kommerell diverticulum. Indications for intervention included a large Kommerell diverticulum (n = 18), dysphagia lusoria (n = 12), rupture (n = 4), type B aortic dissection (n = 4), thoracic aortic aneurysm (n = 2), and coarctation (n = 1). Patients were treated with either open surgery (n = 9) or an endovascular approach (n = 13). For the open surgical patients, hypothermic circulatory arrest (n = 7) or left heart bypass (n = 2) was used. For those patients undergoing an endovascular approach (n = 13), carotid to subclavian arterial bypasses were performed preoperatively in 11 patients and intraoperatively in 2 patients. Bilateral revascularization was more frequently performed with endovascular repair compared with open surgery (69% vs 22%, p = 0.01). RESULTS: Early outcomes included in-hospital mortality (n = 1), stroke (n = 1), and permanent spinal cord ischemia (n = 1) after endovascular approaches, and renal failure requiring dialysis (n = 1) and need for tracheostomy (n = 1) after open repair. The frequency of endovascular repair increased after the commercialization of thoracic endovascular aortic repair in 2005 from 33% to 63%. Four patients developed type I (n = 1) or type II (n = 3) endoleaks, of which 1 required reintervention. Median hospital stay was 7 days (interquartile range 4 to 17). Five-year survival was 81.8%. No late aortic ruptures occurred and 3 patients required late reintervention; 1 after an open and 2 after an endovascular approach. Dysphagia lusoria was relieved in all patients except for 1 in the open repair and 1 in the endovascular group. CONCLUSIONS: Aberrant subclavian arteries and associated Kommerell diverticulum can be treated with acceptable rates of mortality and morbidity. The evolution toward an endovascular approach did not appear to affect late outcomes, suggesting that the choice of treatment should be based on patient-specific anatomy and associated comorbidities.

Outcomes after late explantation of aortic endografts depend on indication for explantation.

BACKGROUND: With the growing prevalence of endovascular repair for abdominal aortic aneurysm (AAA), the number of patients requiring graft explantation is increasing. Therefore, knowledge related to outcomes after explantation may lead to improvement in surgical options. In this study we compare our experience with explantation of aortic endografts, based on indication. METHODS: The medical records of all aortic procedures performed at our center were queried during the period from 2002 to 2012. Relevant data from patients needing explantation of aortic endografts were analyzed using Fisher's exact test, t-test, and Kaplan-Meier analysis. RESULTS: Thirty-nine patients underwent aortic endograft explantation (64.1% men). Mean age was 71.9 years with a mean aneurysm size of 6.8 cm (range 3.5-10.7 cm). Hypertension (97.4%), hyperlipidemia (76.9%), and history of smoking (82%) were the most prevalent risk factors. Mean time to explant was 41.7 months (range 2.2-118.4 months). The primary explant indication was endoleak in 27 (69.2%) and infection in 12 (30.8%) patients. The endoleak group consisted of 13 type I, 8 type II, 1 type III, 4 endotension, 1 rupture, and 4 patients with multiple endoleaks. Seven patients were symptomatic, whereas 2 had ruptured aneurysms. Half of the patients in the infection group required supraceliac clamping for explantation. Operative blood loss (P = 0.08) and need for transfusion (P = 0.005) were significantly higher in the infection group. Thirty-day morbidity was 51.8% for the endoleak group and 83% for the infection group (P = 0.08). There were only 2 deaths in the cohort within 30 days, both in the infection group. Twenty-seven patients were alive at a mean follow-up of 1.9 years (range 0.1-8.4 years). CONCLUSIONS: Endograft explantation is a challenging operation with high morbidity and mortality. Furthermore, patients with an infectious etiology have significantly worse outcomes than those requiring explantation for endoleaks.

Diagnosis, prevention, and treatment of claudication.

Lower extremity chronic ischemia due to atherosclerosis represents the continuum of peripheral arterial disease, encompassing intermittent claudication, rest pain, and tissue loss. Traditionally, the indication for invasive intervention has been critical limb ischemia as a means to prevent amputation. This article highlights claudication and reviews its diagnosis, available treatment modalities, and preventative measures.

Surgical treatment of Kommerell's diverticulum and other saccular arch aneurysms.

BACKGROUND: Saccular aneurysms of the aortic arch are rare, and their surgical repair is challenging with potentially significant morbidity and mortality. METHODS: We examined our experience over a 3-year period with nine consecutive patients that include nine hybrid repairs with initial extra-anatomic carotid and/or subclavian bypass and subsequent endovascular exclusion of the saccular arch aneurysm. RESULTS: Three patients presented with dysphagia from aberrant right subclavian arteries with aneurysm at the origin of the artery, two had asymptomatic aneurysms at the origin of the left subclavian, and four patients had isolated saccular aneurysms of the arch, three of whom presented with thoracic pain. A total of 16 extra-anatomic bypasses were done in the nine patients. Ten endografts and one nitinol plug were used for exclusion in the nine hybrid cases. There were no perioperative deaths, no strokes, or myocardial infarction events. During follow-up, two patients (22%) were found to have type II endoleaks, but no reinterventions were required. Symptoms resolved in six patients, whereas persistent dysphagia and pain occurred in one. CONCLUSIONS: Repair of saccular aneurysms of the aortic arch by hybrid approach can be done with minimal morbidity and mortality and a reasonable rate of symptom resolution.

Post-operative diabetes insipidus after endoscopic transsphenoidal surgery.

Diabetes insipidus (DI) after endoscopic transsphenoidal surgery (ETSS) can lead to increased morbidity, longer hospital stays, and increased medication requirements. Predicting which patients are at high risk for developing DI can help direct services to ensure adequate care and follow-up. The objective of this study was to review our institution's experience with ETSS and determine which clinical/laboratory variables are associated with DI in this patient population. The authors wanted to see if there was an easily determined single value that would help predict which patients develop DI. This represents the largest North American series of this type. We retrospectively reviewed the charts of patients who had undergone ETSS for resection of sellar and parasellar pathology between 2006 and 2011. We examined patient and tumor characteristics and their relationship to postoperative DI. Out of 172 endoscopic transsphenoidal surgeries, there were 15 cases of transient DI (8.7%) and 14 cases of permanent DI (8.1%). Statistically significant predictors of postoperative DI (p < 0.05) included tumor volume and histopathology (Rathke's cleft cyst and craniopharyngioma). Significant indicators of development of DI were postoperative serum sodium, preoperative to postoperative change in sodium level, and urine output prior to administration of 1-deamino-8-D-arginine vasopressin. An increase in serum sodium of ≥2.5 mmol/L is a positive marker of development of DI with 80% specificity, and a postoperative serum sodium of ≥145 mmol/L is a positive indicator with 98% specificity. Identifying perioperative risk factors and objective indicators of DI after ETSS will help physicians care for patients postoperatively. In this large series, we demonstrated that there were multiple perioperative risk factors for the development of DI. These findings, which are consistent with other reports from microscopic surgical series, will help identify patients at risk for diabetes insipidus, aid in planning treatment algorithms, and increase vigilance in high risk patients.

A systematic update on the state of novel anticoagulants and a primer on reversal and bridging.

BACKGROUND: Current prevention and treatment of venous thromboembolism (VTE) includes familiar agents that have been in use for many years, including unfractionated heparin, low-molecular-weight heparin (LMWH), and vitamin K antagonists (VKAs). A number of novel oral anticoagulants are currently developed or are in stages of development to either replace VKAs in concert with initial heparin or LMWH, or to replace both heparin/LMWH and VKAs totally as monotherapy. These agents hold the promise of not requiring monitoring, being safer in terms of bleeding risk than current agents, and being of equal or improved efficacy compared with established anticoagulants. METHODS: In the following report, we systematically review the oral agents currently approved or closest to approval for both VTE and atrial fibrillation treatment, focusing on the treatment of VTE: dabigatran, rivaroxaban, and apixaban. RESULTS: Findings of clinical use and comparisons to standard care of these agents are summarized in depth, by succinctly reviewing all major randomized controlled trials. Mechanistic and functional differences are reviewed, as Dabigatran targets activated factor II (factor IIa), while rivaroxaban and apixaban target activated factor X (factor Xa). We also discuss the inability at the present time to reliably reverse the anticoagulant effects of these agents, provide a suggested strategy for reversal, and finally discuss an approach to bridging these agents when other procedures are required while currently taking one of these three agents. CONCLUSIONS: These agents, while still with many unanswered questions, demonstrate great promise in the prevention and treatment of VTE.

Post-endovascular aneurysm repair patient outcomes and follow-up are not adversely impacted by long travel distance to tertiary vascular surgery centers.

BACKGROUND: To determine whether patient adherence to follow-up and patient outcomes after endovascular aneurysm repair (EVAR) are affected by the distance between a patient's residence and a tertiary care treatment center. METHODS: A retrospective review of 136 consecutive patients undergoing EVAR at the New Mexico Veterans Affairs Medical Center over a 7-year period was conducted. Patients were stratified as living within a 100-mi radius of the treatment center (group 1) and those living outside this radius (group 2). Follow-up included clinic visits and computed tomography scans at 1 month after discharge, every 6 months for 2 years, and then yearly. Incomplete follow-up was defined if two or more consecutive appointments were missed. Survival and graft-related complication rates were analyzed for both the patient groups. RESULTS: Of the 136 patients, 10 patients died from nonaneurysm-related causes less than 1 year after their EVAR procedures, and hence were not a part of the study. Of the surviving patients, 44% lived within a 100-mi radius of the treatment center (group 1), and 56% outside this 100-mi radius (group 2). The mean patient follow-up time was 52.1 ± 25.9 months. Of the surviving patients, 15% had inadequate follow-up, yet there was no significant difference in the adequacy of follow-up for patients in group 1 compared with group 2. The incidence of major complications, defined as aneurysm rupture, conversion to open repair, myocardial infarction, and stroke, was not statistically different in group 1 versus group 2 (5.0% vs. 11.8%, p = 0.23). Of the five patients (3.7%) who died as a result of abdominal aortic aneurysms related causes, three were in group 1 and two in group 2. CONCLUSIONS: Distance from a tertiary care center is not a limiting factor in patient adherence to follow-up, patient graft-related morbidity, or patient survival, likely because of the Albuquerque VA Medical Center's electronic tracking of patients and provision of travel vouchers.

A review of clinical trials and registries in descending thoracic aortic aneurysms.

Aortic disease is a significant pathology, as it represents the 12(th) leading cause of overall death. Aneurysms of the descending thoracic aorta pose a small but significant part of this pathology. Traditional open descending thoracic aortic aneurysm (TAA) repair continues to be performed despite relatively high morbidity and mortality rates. As endovascular therapy to treat vascular disease has evolved, a paradigm shift has occurred such that likely most isolated TAAs are now repaired with an endovascular approach. Multiple, prospective trials have been performed comparing open and endovascular TAA repair with three company sponsored trials documenting clinical equipoise. In these studies, endovascular thoracic aortic aneurysm repair (ETAR) was mostly compared with historic controls or open repair from centers of excellence. While the trials all indicate that 30-day peri-operative morbidity and mortality is lower in the ETAR group, these trials were not designed to determine which patient is best served by an open versus an endovascular approach. In addition, long-term follow-up data is limited. Registry data of patients undergoing ETAR seems to mirror that of the aforementioned clinical trials and indicates acceptable morbidity and mortality profiles when compared to published open TAA repair results. Future prospective studies focused on patient selection likely will never be performed, as most believe the benefits of ETAR outweigh the lack of long term follow up data. This review will focus on repair of TAA, specifically clinical trial and registry data comparing open and endovascular repair.