Jayer Chung

Left subclavian artery coverage during thoracic endovascular aortic repair and risk of perioperative stroke or death

INTRODUCTION Left subclavian artery (LSA) coverage during thoracic endovascular aortic repair (TEVAR) is often necessary due to anatomic factors and is performed in to up to 40% of procedures. Despite the frequency of LSA coverage during TEVAR, reported associations with risk of periprocedural stroke or death are inconsistent in reported literature. We examined the 2005-2008 American College of Surgeons National Surgical Quality Improvement Program Participant Use Data file to determine associations between LSA coverage during TEVAR and risk of perioperative stroke or death. METHODS Current procedural terminology (CPT) codes were used to identify patients undergoing TEVAR, LSA coverage, and subclavian revascularization. Patients undergoing coronary bypass, ascending aortic repair, abdominal aortic aneurysm repair, or nonvascular intra-abdominal procedures during the same operation were excluded. Perioperative stroke and mortality associations with LSA coverage were examined using logistic regression models for each outcome. Significance was assessed at α = 0.05, with univariable P < .05 required for multivariable model entry. RESULTS Eight hundred forty-five TEVAR procedures were identified, of which 52 patients were excluded due to additional major procedures performed with TEVAR. Seven hundred thirty-three of the remaining 793 procedures included CPT codes indicating primary placement of an initial thoracic endograft and form the basis of this analysis. LSA coverage occurred in 279 procedures (38%). Thirty-day stroke and mortality rates were 5.7% and 7.0%, respectively. LSA coverage was associated with increased 30-day risk of stroke in multivariable modeling (odds ratio [OR], 2.17 95% confidence interval [CI], 1.13-4.14; P = .019). Other significant multivariable risk factors for stroke included proximal aortic cuff placement during TEVAR (OR, 2.58; 95% CI, 1.30-5.16; P = .007) and emergency procedure status (OR, 3.60; 95% CI, 1.87-6.94; P < .001). No significant association between LSA coverage and perioperative mortality was identified (univariable OR, 1.70; 95% CI, 0.98-2.93; P = .0578). CONCLUSION LSA coverage during thoracic endovascular repair is associated with increased risk of perioperative stroke following TEVAR. Further evidence is needed to determine whether procedural modifications, including LSA revascularization, reduce the incidence of stroke associated with TEVAR.

Multidisciplinary care improves amputation-free survival in patients with chronic critical limb ischemia.

BACKGROUND This study was conducted to quantify the effect of multidisciplinary care (MDC) on amputation-free survival (AFS) and wound healing within a chronic critical limb ischemia (CLI) population. METHODS We performed a retrospective, single-center cohort study of consecutive CLI patients presenting to the Vascular Surgery Service. Patients who received initial and follow-up wound care from the MDC were compared with patients who received standard wound care (SWC). The MDC team consisted of vascular, plastic, and podiatric surgeons who jointly managed wound care and directed any other consults or services as deemed necessary. SWC consisted of an inconsistent mix of providers without a defined manager, including nurses, wound care midlevel providers, general surgeons, internists, or the patients themselves. The referring physician determined the allocation of patients. The primary outcome variable was AFS, with a secondary evaluation of wound healing. The effects of baseline demographics, comorbid medical conditions, laboratory values, ischemic lesion severity and location, Rutherford classification, and participation in MDC were assessed. Significant univariate predictors (P < .10) of AFS were entered into a multivariate Cox regression model and assessed at an α = .05. RESULTS Between August 2010 and June 2012, 146 CLI patients (91 male [63%]) were evaluated by the Vascular Surgery Service and were followed up for a median of 539 days (interquartile range 314-679 days). Ischemic tissue loss was present in 85 patients (38 at Rutherford category 5, and 47 at Rutherford category 6). Within this cohort, 51 (60%) had MDC, and 34 (40%) had SWC. Fifty-eight patients (68%) underwent revascularization (open in 17, endovascular in 35, and hybrid in 6), 14 (8%) were managed with primary major amputation, and 13 (15%) declined revascularization. AFS was superior for patients in the MDC arm vs the SWC arm (593.3 ± 53.5 days vs 281.0 ± 38.2 days; log-rank, P = .02). Wound-healing times favored the MDC arm over the SWC arm (444.5 ± 33.2 days vs 625.2 ± 126.5 days), although this was not statistically significant (log-rank, P = .74). Multivariate modelling revealed that independent predictors of major amputation or death, or both, were nonrevascularized patients (hazard ratio [HR], 3.76; 95% confidence interval [CI], 1.78-8.02; χ(2), P < .01), treatment by SWC (HR, 2.664; 95% CI, 1.23-5.77; χ(2), P = .012), and baseline nonambulatory status (HR, 1.89; 95% CI, 1.17-2.85; χ(2), P < .01). CONCLUSIONS MDC pathways for the management of a population of CLI patients improved AFS by greater than twofold and should be the standard of care for the CLI population. Baseline nonambulatory status and unrevascularized patients also predict worse AFS. Wound healing remains prolonged regardless of preoperative or postoperative wound care. Future study is required to evaluate the costs and functional outcomes for MDC in the management of CLI.

Surgeon education decreases radiation dose in complex endovascular procedures and improves patient safety

OBJECTIVE Complex endovascular procedures such as fenestrated endovascular aneurysm repair (FEVAR) are associated with higher radiation doses compared with other fluoroscopically guided interventions (FGIs). The purpose of this study was to determine whether surgeon education on radiation dose control can lead to lower reference air kerma (RAK) and peak skin dose (PSD) levels in high-dose procedures. METHODS Radiation dose and operating factors were recorded for FGI performed in a hybrid room over a 16-month period. Cases exceeding 6 Gy RAK were investigated according to institutional policy. Information obtained from these investigations led to surgeon education focused on reducing patient dose. Points addressed included increasing table height, utilizing collimation and angulation, decreasing magnification modes, and maintaining minimal patient-to-detector distance. Procedural RAK doses and operating factors were compared 8 months pre- (group A) and 8 months post- (group B) educational intervention using analysis of variance with Tukey pairwise comparisons and t-tests. PSD distributions were calculated using custom software employing input data from fluoroscopic machine logs. RESULTS Of 447 procedures performed, 300 FGIs had sufficient data to be included in the analysis (54% lower extremity, 11% thoracic endovascular aneurysm repair, 10% cerebral, 8% FEVAR, 7% endovascular aneurysm repair, 5% visceral, and 5% embolization). Twenty-one cases were investigated for exceeding 6 Gy RAK. FEVAR comprised 70% of the investigated cases and had a significantly higher median RAK dose compared with all other FGIs (P < .0001). There was no difference in body mass index between groups A and B; however, increasing body mass index was an indicator for increased RAK. PSD calculations were performed for the 122 procedures that focused on the thorax and abdomen (group A, 80 patients; group B, 42 patients). Surgeon education most strongly affected table height, with an average table height elevation of 10 cm per case after education (P < .0001). The dose index (PSD/RAK ratio) was used to track changes in operating practices, and it decreased from 1.14 to 0.79 after education (P < .0001). These changes resulted in an estimated 16% reduction in PSD. There was a trend toward a decrease in patient to detector distance, and the use of collimation increased from 25% to 40% (P < .001) for all cases; however, these did not result in a decrease in PSD. The number of cases that exceeded 6 Gy RAK did not change after education; however, the proportion of non-FEVAR cases that exceeded 6 Gy decreased from 40% to 20%. CONCLUSIONS Surgeon education on the appropriate use of technical factors during FGIs improved operating practice, reduced patient radiation dose, and decreased the number of non-FEVAR cases that exceeded 6 Gy. It is essential that vascular surgeons be educated in best operating practices to lower PSD; nonetheless, FEVAR remains a high-dose procedure.

Neoaortoiliac system (NAIS) Procedure for the treatment of the infected aortic graft

We aim to provide a thorough and current summary highlighting the use of autologous vein grafts during reconstruction of infected aortic grafts. Aortic graft infections, while rare, remain one of the most difficult problems that a vascular surgeon can encounter. Optimal management of patients with aortic graft infections requires a full understanding of all potential therapeutic interventions available. Reconstruction with autologous vein grafts is a technique that has evolved and has been refined during the past 2 decades, representing a major advance in the treatment of aortic graft infections. Thirty-day operative mortality is ≤ 10%, with 5-year mortality rates of 30% to 50%. Thirty-day major amputation rates range from 2% to 7.4%, with 5-year limb-salvage rates ranging between 89% and 96%. Early occlusion of the grafts are rare, with <4% undergoing thrombosis within the first 30 days; 5-year primary patency ranges from 75% to 91%, with secondary patency approaching 91% at 5 years. Recurrent infection is very rare, occurring in <2% of patients. Venous morbidity is similarly low, with fasciotomy rates of 12%, and only 15% of patients experiencing chronic venous insufficiency at 5 years. Aneurysmal degeneration is also exceptionally rare. Use of autologous vein grafts for in situ reconstruction of infected aortic grafts represents the standard of care in the treatment of aortic graft infections. With appropriate patient selection, centers with sufficient resources should be able to comparable outcomes.

Optimal medical therapy predicts amputation-free survival in chronic critical limb ischemia

OBJECTIVE Determine the proportion of patients with chronic critical limb ischemia (CLI) who failed to adhere to Trans-Atlantic Inter-Society Consensus II guidelines of medical therapy and to quantify the effect of baseline suboptimal medical management on amputation-free survival (AFS). METHODS The patients were identified from a prospectively maintained database of consecutive patients presenting with CLI to the Vascular Surgery service at a single hospital. The primary outcome variable was AFS. The effects of baseline demographics, comorbid medical conditions, ambulatory status, optimal medical management, and Rutherford classification were assessed. Significant univariate predictors (P < .10) of AFS were entered into a multivariate Cox proportional hazards model. RESULTS From August 1, 2010 through January 1, 2012, 98 patients (median age, 59.0; interquartile range, 53, 64 years; 58 men) were evaluated with rest pain (n = 40) or tissue loss (n = 58). Optimal medical management was identified in 31 (32%) patients at initial presentation. Compliance rates for the entire cohort were 61% for statin use, 69% for antiplatelet therapy, 56% for angiotensin-converting enzyme inhibitor use, and 53% for beta-blocker use. Significant univariate predictors of major amputation or death included: Rutherford classification (hazard ratio [HR], 1.56; 95% confidence interval [CI], 1.01-2.41; P = .04); nonambulatory status (HR, 2.17; 95% CI, 1.68-2.81; P < .01); unrevascularized patients (HR, 2.77; 95% CI, 1.32-5.85; P < .01); a history of tobacco abuse (HR, 1.49; 95% CI, 0.57-3.86; P = .09); a history of end-stage-renal disease (HR, 7.97; 95% CI, 3.10-20.52; P < .01); suboptimal medical management (HR, 4.25; 95% CI, 1.28-14.07; P = .02); and an absence of antiplatelet agents (HR, 1.94; 95% CI, 0.92-4.11; P = .08). Independent predictors of major amputation or death included: initial nonambulatory status (HR, 2.43; 95% CI, 1.03-2.05; P < .01); unrevascularized status (HR, 2.43; 95% CI, 1.76-3.34; P = .01); and suboptimal medical management at presentation (HR, 8.54; 95% CI, 2.05-35.65; P < .01). CONCLUSIONS Despite guidelines advocating the optimization of atherosclerotic risk factors, less than one-third of patients with CLI present with their risk factors optimally managed. Patients who are medically undertreated have an eight-fold risk of major amputation and/or death. The magnitude of the effect suggests that future trials and quality assessments should stratify outcomes by the quality of baseline medical management. Of the risk factors affecting AFS medical therapy optimization is the variable that can be most significantly improved by vascular surgeons and the medical community.

Risk factors for late mortality after endovascular repair of the thoracic aorta

OBJECTIVE This study was conducted to identify risk factors for late mortality after thoracic endovascular aortic repair (TEVAR). METHODS A retrospective analysis of consecutive TEVAR was conducted. Medical record review, telephone contact, or query of the Social Security Death Index was used to determine 30-day and late survival. Late mortality was assessed with respect to patient characteristics at the time of the initial treatment, preoperative laboratory values, pathology, clinical presentation, and treatment adjuncts. Significant univariate predictors of death were entered into a multivariate Cox proportional hazards model. RESULTS From 1998 to 2009, 252 patients (149 men; mean age, 68 years) underwent TEVAR for degenerative thoracic aortic aneurysm (TAA, n = 143), type B dissection (n = 62), mycotic aneurysm (n = 13), traumatic disruption (n = 12), penetrating ulcer or intramural hematoma (n = 10), anastomotic pseudoaneurysm (n = 4), or other pathology (n = 8). The 30-day mortality was 9.5%, with stroke or spinal cord injury in 5.6%. Mean follow-up was 22 +/- 22 months. Kaplan-Meier mean survival was 53 months. Predictors of late mortality by univariate analysis included age (P < .01), cardiac arrhythmia (P = .03), chronic obstructive pulmonary disease (P = .05), aneurysm diameter (P < .01), rupture (P < .01), debranching (P = .02), leukocytosis (white blood cell count > 10.0 x 10(3)/microL; P < .01), albumin, (P < .01), and creatinine > 1.7 mg/dL (P = .01). Multivariate predictors of mortality included rupture (hazard ratio [HR], 3.10; 95% confidence interval [CI], 1.02-9.44; P = .03), debranching (HR, 2.20; 95% CI, 1.09-4.24; P = .03), preoperative leukocytosis (HR, 1.23; 95% CI, 1.09-1.39; P = .001), and aneurysm diameter (HR, 1.02; 95% CI, 1.01-1.03; P = .04). Subgroup analysis of patients undergoing TEVAR for asymptomatic, nonruptured TAA demonstrated that debranching (HR, 2.47; 95% CI, 1.13-5.39; P = .02), White blood cell count (HR, 1.19; 95% CI, 1.01-1.40; P < .04), and aneurysm diameter (HR, 1.03; 95% CI, 1.01-1.05, P < .01) remain independently predictive of late mortality. CONCLUSIONS Preoperative leukocytosis, aneurysm diameter, and concurrent debranching independently predict late mortality irrespective of clinical presentation and may assist in risk stratification.

The need for improved risk stratification in chronic critical limb ischemia

Vascular surgeons are well acquainted with chronic critical limb ischemia (CLI), the most severe manifestation of peripheral arterial disease, with patients presenting with ischemic rest pain or ulcerations, or both. Epidemiologic data predict a burgeoning epidemic of CLI within the United States, commensurate with the increasing incidence and prevalence of atherosclerotic risk factors, especially age and diabetes. Untreated, the risk of major amputation (above the ankle) or death, or both, ranges between 20% and 40% at 1 year. Current open and endovascular therapies have imperfect results, diverse treatment options, and recommendations that are often conflicting and confuse physicians, industry, and patients alike. The best treatment options are ideally evaluated by prospective, randomized controlled trials. However, these have proven impractical in CLI because the rapid evolution of devices and techniques has outstripped the ability to measure outcomes and compare treatment options. Alternatively, risk-stratifying models have been proposed to allow physicians, patients, and industry to objectively evaluate new therapeutics and devices as they evolve. These models are developed from prospective cohorts to identify and quantify variables that can subsequently predict outcome in individual patients. The risk stratification models can also compare CLI outcomes between physicians and institutions, supporting quality assessments, and compensation decisions within Accountable Care Organizations under the Affordable Health Care Act (ACA). Widespread adoption of risk-stratification schemes has yet to occur, despite the critical need for such a tool in CLI, because present models lack optimal predictive ability and generalizability. The passage of the ACA amplifies the importance of developing an improved risk-stratification tool to ensure equitable quality assessments and compensation. This review presents current risk-stratification models for CLI with a summary of the respective strengths and limitations of each. Future research is needed to simplify and improve the accuracy and generalizability of risk stratification in CLI.

Midterm results of adjunctive neck therapies performed during elective infrarenal aortic aneurysm repair

OBJECTIVE This study evaluated the durability of adjunctive endovascular neck procedures, including aortic cuffs, Palmaz stents (Cordis, Miami Lakes, Fla), and high-pressure balloon angioplasty, at managing intraoperative proximal neck complications during endovascular aortic aneurysm repair (EVAR). METHODS This was a single-center retrospective review of EVARs. The primary outcome variable studied was survival free of a graft-related event (GRE). GRE was defined by the occurrence of one of the following: type I endoleak, sac enlargement, aneurysm rupture, death, or procedure related to the aortic neck. These outcome variables were assessed relative to the preoperative anatomic neck variables (neck length, diameter, degree of angulation, degree of circumferential thrombus, and presence of conicity), procedural variables (manufacturing type of graft, use of a Palmaz stent), and patient characteristics (age and presence of medical comorbidities). Outcomes were assessed by t tests, Pearson χ(2), and Kaplan-Meier analysis, when appropriate. RESULTS A total of 174 EVARs performed between January 2005 and December 2007 were evaluated. Fifty-six adjunctive procedures were performed, with a 97% primary-assisted exclusion rate. Patients who received an adjunctive therapy had similar freedom from a GRE compared with EVARs that did not require adjunctive therapy (35.5 ± 2.6 vs 34.8 ± 1.5 months, P = .31, log-rank test). Subset analysis identified a significant association between Palmaz stent placement at the time of EVAR and decreased freedom from GREs (hazard ratio, 2.87; 95% confidence interval, 1.21-6.77; P = .02). CONCLUSIONS Midterm results suggest that adjunctive therapies to manage intraoperative proximal neck complications do not compromise durability. The subset of patients requiring aortic neck Palmaz stent placement at the time of EVAR are among those at highest risk for subsequent GRE.

Assessing outcomes to determine whether symptoms related to hypertension justify renal artery stenting

OBJECTIVE The goal of the study was to determine the blood pressure (BP) response to renal artery stenting (RAS) for patients with hypertension urgency, hypertension emergency, and angina with congestive heart failure (angina/congestive heart failure [CHF]). METHODS Patients who underwent RAS for hypertension emergencies (n = 13), hypertension urgencies (n = 25), and angina/CHF (n = 14) were included in the analysis. By convention, hypertension urgency was defined by a sustained systolic BP ≥ 180 mm Hg or diastolic BP ≥ 120 mm Hg, while the definition of hypertension emergency required the same BP parameters plus hypertension-related symptoms prompting hospitalization. Patient-specific response to RAS was defined according to modified American Heart Association reporting guidelines. RESULTS The study cohort of 52 patients had a median age of 66 years (interquartile range 58-72). The BP response to RAS varied significantly according to the indication for RAS. Hypertension emergency provided the highest BP response rate (85%), while the response rate was significantly lower for hypertension urgency (52%) and angina/CHF (7%; P = .03). Only 1 of 14 patients with angina/CHF was a BP responder. Multivariate analysis showed that hypertension urgency or emergency were not independent predictors of BP response to RAS. Instead, the only independent predictor of a favorable BP response was the number of preoperative antihypertensive medications (odds ratio 7.5; 95% confidence interval 2.5-22.9; P = .0004), which is another indicator of the severity of hypertension. Angina/CHF was an independent predictor of failure to respond to RAS (odds ratio 118.6; 95% confidence interval 2.8-999.9; P = .013). CONCLUSIONS Hypertension urgency and emergency are clinical manifestations of severe hypertension, but the number of preoperative antihypertensive medications proved to be a better predictor of a favorable BP response to RAS. In contrast, angina/CHF was a predictor of failure to respond to stenting, providing further evidence against the practice of incidental stenting during coronary interventions.

Clinical significance of standing versus reversed trendelenburg position for the diagnosis of lower-extremity venous reflux in the great saphenous vein

Introduction Sonographic detection of incompetence in the deep and superficial veins requires proper patient positioning. Although these tests have been traditionally performed in the reversed Trendelenburg (RT) position, recent mandates from The Intersocietal Commission for the Accreditation of Vascular Laboratories and some insurance providers require that patients be evaluated for reflux in the standing position (SP). The purpose of this study was to determine whether performing venous duplex in the SP versus RT position adds information that affects patient treatment. Methods Twenty-eight subjects (25 women; mean age of 52 years) with signs and symptoms of venous insufficiency were evaluated prospectively with the use of ultrasound imaging and Doppler in the 5- to 8-MHz ranges. The great saphenous vein (GSV) was evaluated for each limb from below the knee to the saphenofemoral junction. Patients were initially evaluated at 15–25 degrees of RT position. Reflux was defined by reversal of flow for >0.5 seconds via use of the Valsalva and/or manual compression maneuvers. The GSV was measured in A-P diameter at the saphenofemoral junction and at the knee level. The subjects were then elevated to SP and measurements were repeated while the limb was in a nonweight-bearing position. Results A total of 52 limbs were evaluated for venous reflux in 28 study subjects. The mean lower-extremity CEAP score was 3 SD ± 3. Twenty-six (50%) GSVs were positive for venous reflux in the RT position. Of these GSVs, three were negative for reflux in SP. Twenty-seven (53%) GSVs were positive for venous reflux in SP; however, four of these GSVs were negative for reflux in RT. The median difference in reflux time from RT to SP was 0.15 seconds (interquartile range 0–3.8 seconds and 0–2.7seconds, respectively, p = 0.02). The mean difference in GSV diameter from RT to SP was 0.7 mm (±0.96 mm SD, p < 0.0001). These results changed the clinical course for one subject who did not have reflux in RT but did in SP (3.5%, p = 0.085). Conclusion The results from evaluating subjects in SP were not independently associated with a change in clinical outcome. However, 15% of GSVs negative for reflux in RT were positive for reflux in the SP. As a result, 3.5% of subjects in our study had a change in clinical course as the result of evaluation of the GSV in SP. This finding suggests that failure to identify GSV reflux in RT in patients with signs and symptoms of venous insufficiency may be an indication to evaluate the GSV in SP.