Contemporary outcomes for arterial reconstruction with non-saphenous vein cryo-preserved conduits.

OBJECTIVE: Cryopreserved (CP) products are utilized during challenging cases when autogenous or prosthetic conduit use is not feasible. Despite decades of experience with cadaveric greater saphenous vein (GSV), there is limited available data regarding the outcomes and patency of other CP products, specifically arterial and deep venous grafts. This study was designed to evaluate outcomes of non-GSV CP conduits in patients undergoing urgent, emergent, and elective arterial reconstruction at our institution. We hypothesized that non-GSV CP allografts have adequate patency and outcomes and are therefore a feasible alternative to GSV in settings where autologous graft is unavailable or prosthetic grafts are contraindicated. METHODS: This study was approved by the Institutional Review Board at our institution. We retrospectively reviewed charts of patients undergoing arterial reconstructions using CP conduits from 2010 to 2022. Data collected included demographics, comorbidities, smoking status, indications for surgery, indication for CP conduit use, anatomic reconstruction, urgency of procedure, and blood loss. Time-to-event outcomes included primary and secondary graft patency rates, follow-up amputations, and mortality; other complications included follow-up infection/reinfection and 30-day complications, including return to the operating room and perioperative mortality. Time-to-event analyses were evaluated using product-limit survival estimates. RESULTS: Of 96 identified patients receiving CP conduits, 56 patients received non-GSV conduits for 66 arterial reconstructions. The most common type of non-GSV CP product used was femoral artery (31 patients), followed by aorto-iliac artery (22 patients), and femoral vein (19 patients), with some patients receiving more than one reconstruction or CP product. Patients were mostly male (75%), with a mean age of 63.1 years and a mean body mass index of 26.7 kg/m2. Indications for CP conduit use included infection in 53 patients, hostile environment in 36 patients, contaminated field in 30 patients, tissue coverage concerns in 30 patients, inadequate conduit in nine patients, and patient preference in one patient. Notably, multiple patients had more than one indication. Most surgeries (95%) were performed in urgent or emergent settings. Supra-inguinal reconstructions were most common (53%), followed by extra-anatomic bypasses (47%). Thirty-day mortality occurred in 10 patients (19%). Fifteen patients (27%) required return to the operating room for indications related to the vascular reconstructions, with 10 (18%) cases being unplanned and five (9%) cases planned/staged. Overall survival at 6, 12, and 24 months was 80%, 68%, and 59%, respectively. Primary patency at 6, 12, and 24 months was 86%, 70%, and 62%, respectively. Amputation freedom at 6 months, 12 months, and 24 months was 98%, 95%, and 86%, respectively for non-traumatic indications. CONCLUSIONS: Non-GSV CP products may be used in complex arterial reconstructions when autogenous or prosthetic options are not feasible or available.

Prevalence of chronic opioid use in patients with peripheral arterial disease undergoing revascularization.

OBJECTIVE: Opiate use, dependence, and the associated morbidity and mortality are major current public health problems in the United States. Little is known about patterns of opioid use in patients with peripheral arterial disease (PAD). The purpose of this study was to identify the prevalence of chronic preoperative and postoperative prescription opioid use in patients with PAD. A secondary aim was to determine the demographic, comorbid conditions, and operative characteristics associated with chronic opioid use. METHODS: Using a single-institution database of patients with PAD undergoing open or endovascular lower extremity intervention from 2013 to 2014, data regarding opiate use and associated conditions were abstracted for analysis. Patients were excluded if they did not live in North Carolina or surgery was not for PAD. Preoperative (PreCOU) and postoperative chronic opioid use (PostCOU) were defined as consistent opioid prescription filling in the 3 months before and after the index procedure, respectively. Opioid prescription filling was assessed using the North Carolina Controlled Substance Reporting System. Demographics, comorbid conditions, other adjunct pain medication data, and operative characteristics were abstracted from our institutional electronic medical record. Associations with PreCOU were evaluated using the t test, Wilcoxon test, or two-sample median test (continuous), or the χ2 or Fisher exact tests (categorical). RESULTS: A total of 202 patients undergoing open (108; 53.5%) or endovascular (94; 46.5%) revascularization for claudication or critical limb ischemia were identified for analysis. The mean age was 64.6 years, and 36% were female. Claudication was the indication for revascularization in 26.7% of patients, and critical limb ischemia was the indication in 73.3% of patients. The median preoperative ankle-brachial index (ABI) was 0.50. Sixty-eight patients (34%) met the definition for PreCOU. PreCOU was associated with female gender, history of chronic musculoskeletal pain, benzodiazepine use, and self-reported illicit drug use. Less than 50% of patients reported use of non-opiate adjunct pain medications. No association was observed between PreCOU and pre- or postoperative ABI, or number of prior lower extremity interventions. Following revascularization, the median ABI was 0.88. PreCOU was not associated with significant differences in postoperative complications, length of stay, or mortality. Overall, 71 patients (35%) met the definition for PostCOU, 14 of whom had no history of preoperative chronic opiate use. Ten patients with PreCOU did not demonstrate PostCOU. CONCLUSIONS: Chronic opiate use was common in patients with PAD with a prevalence of approximately 35%, both prior to and following revascularization. Revascularization was associated with a termination of chronic opiate use in less than 15% of patients with PreCOU. Additionally, 10% of patients who did not use opiates chronically before their revascularization did so afterwards. Patients with PAD requiring intervention represent a high-risk group with regards to chronic opiate use. Increased diligence in identifying opioid use among patients with PAD and optimizing the use of non-narcotic adjunct pain medications may result in a lower prevalence of chronic opiate use and its attendant adverse effects.

Outpatient grip strength measurement predicts survival, perioperative adverse events, and nonhome discharge among patients with vascular disease.

OBJECTIVES: Frailty is associated with adverse outcomes among patients with vascular disease. Grip strength measurement is a comparatively simple, quick, and inexpensive screening test for weakness (a component of frailty) that is potentially applicable to clinical practice. We hypothesized that grip strength and categorical weakness are associated with clinical outcomes among patients with vascular disease. To test this hypothesis, we conducted a longitudinal cohort study evaluating associations between grip strength measured during outpatient clinic visits for vascular disease and clinical outcomes, including survival and perioperative outcomes. METHODS: Adult patients recruited from outpatient vascular surgery and/or vascular medicine clinics underwent dominant hand grip strength measurement using a hand dynamometer. Participants were categorized as weak based on grip strength, sex, and body mass index. Multivariable logistic models were used to evaluate perioperative outcomes. Mortality was evaluated using Cox proportional hazards models adjusted for sex, age, and operative intervention during follow-up. RESULTS: We enrolled 321 participants. The mean patients age was 69.0 ± 9.4 years, and 33% were women. Mean grip strength was 32.0 ± 12.1 kg, and 92 participants (29%) were categorized as weak. The median follow-up was 24.0 months. Adverse perioperative events occurred in 32 of 84 patients undergoing procedures. Grip strength was associated with decreased risk of perioperative adverse events (hazard ratio [HR], 0.41 per 12.7 kg increase; 95% confidence interval [CI], 0.20-0.85; P = .0171) in a model adjusted for open versus endovascular procedure (HR, 12.75 for open; 95% CI, 2.54-63.90; P = .0020) and sex (HR, 3.05 for male; 95% CI, 0.75-12.4; P = .120). Grip strength was also associated with a lower risk of nonhome discharge (HR, 0.34 per 12.7 kg increase; 95% CI, 0.14-0.82; P = .016) adjusted for sex (HR, 2.14 for male; 95% CI, 0.48-9.50; P = .31) and open versus endovascular procedure (HR, 10.36 for open; 95% CI, 1.20-89.47; P = .034). No associations between grip strength and length of stay were observed. Mortality occurred in 48 participants (14.9%) during follow-up. Grip strength was inversely associated with mortality (HR, 0.46 per 12.5 kg increase; 95% CI, 0.29-0.73; P = .0009) in a model adjusted for sex (HR, 5.08 for male; 95% CI, 2.1-12.3; P = .0003), age (HR, 1.04 per year; 95% CI, 1.01-1.08), and operative intervention during follow-up (HR, 1.23; 95% CI, 0.71-2.52). Categorical weakness was also associated with mortality (HR, 1.81 vs nonfrail; P = .048) in a model adjusted for age (HR, 1.06 per year; P = .002) and surgical intervention (HR, 1.36; 95% CI, 1.02-0.09; P = .331). CONCLUSIONS: Grip strength is associated with all-cause mortality, perioperative adverse events, and nonhome discharge among patients with vascular disease. These observations support the usefulness of grip strength as a simple and inexpensive risk screening tool for patients with vascular disease.

Thermal Tolerance May Slow, But Not Prevent, the Spread of Sargassum horneri (Phaeophyceae) along the California, USA and Baja California, MEX Coastline.

Biological invasions have become increasingly prevalent in marine ecosystems, modifying biodiversity and altering the way ecosystems function. Understanding how variation in environmental factors influences the success of non-native species, especially their early life stages, can be a crucial step in identifying habitats that are under threat of invasion, and in predicting how rapidly and far these species may spread once they arrive in novel habitats. The invasive marine macroalga Sargassum horneri was first observed in Long Beach Harbor, CA, USA in 2003, and has since spread throughout the Southern California Bight and along the Baja California Peninsula, MEX where it now forms dense stands on subtidal rocky reefs and displaces native habitat-forming macroalgae. We examined how variation in temperature, nutrients, and irradiance affect survival, growth, and development in S. horneri early life stages over a three-week period. Our experimental treatments consisted of orthogonally crossed temperatures (10, 15, 20, and 25°C), nutrient concentrations (ambient and nutrient-enriched seawater), and irradiances (50 and 500 µmol photons · m-2 · s-1 ). Overall, temperature exerted the greatest influence on S. horneri's germling and juvenile life stages, with moderate temperatures facilitating their greatest survival, growth, and development. In contrast, fewer germlings developed fully under the lowest or highest temperatures, and juvenile survival and growth were reduced, especially when combined with low irradiances. Together, our data suggest that ocean temperatures of or below 10˚C and of or above 25°C may slow, but likely not stop, S. horneri's northward and southward expansion along the California and Baja California coasts.

Variation in Photosynthetic Performance Relative to Thallus Microhabitat Heterogeneity in Lithothamnion australe (Rhodophyta, Corallinales) Rhodoliths.

Rhodoliths are free-living, coralline algae that create heterogeneous structure over sedimentary habitats. These fragile ecosystems are threatened by anthropogenic disturbances that reduce their size and three-dimensional structural complexity. We investigated how physical disturbance from boat moorings affects photosynthetic performance in the rhodolith Lithothamnion australe. Photosynthetic parameters were measured for intact rhodoliths and crushed rhodolith fragments of two sizes (ca. 1 and 2 cm diameter), while chlorophyll fluorescence was measured at the surface of rhodoliths of these two sizes, between the interior branches of the larger rhodoliths, and at the surface of 52 various sized (0.4-3.5 cm diameter) rhodoliths. Gross productivity and net productivity were 15% and 36% higher, respectively, in the smaller L. australe, while respiration was 10% higher in the larger individuals. Thallus crushing reduced gross productivity by 20% and 41%, and net productivity by 9% and 14% in the smaller and larger rhodoliths, respectively. It also reduced respiration by 33% and 60% in the smaller and larger rhodoliths, respectively. Fluorescence parameters were all greater at the surface of the larger L. australe than the smaller individuals, and greater at the surface than in the interior parts of the larger individuals. Across a range of rhodolith sizes, surface fluorescence parameters were at their maxima in 1.54 to 2.32 cm diameter individuals. These results show that L. australe's complex structure creates heterogeneity in photosynthesis and respiration between their surface and interior parts and among rhodolith sizes. This information can help predict how rhodoliths may respond to disturbance and environmental stressors.

Evaluation of Neuropathy, Glycemic Control, and Revascularization as Risk Factors for Future Lower Extremity Amputation among Diabetic Patients.

BACKGROUND: Diabetes mellitus is a major risk factor for progression to lower extremity amputation (LEA) due to progressive neuropathy and glycemia-induced vasculopathy. In this study, we evaluated risk factors for incident LEA type 2 diabetics during a randomized controlled trial and extended post-trial follow-up. METHODS: The Action to Control Cardiovascular Risk in Diabetes trial randomized 10,251 type 2 diabetics to intensive glycemic control (Hemoglobin A1c (HbA1c) target <6.0%) versus standard glycemic control (HbA1c target 7.0-7.9%). Using backward elimination logistic regression models, we examined relationships between neuropathy using the Michigan Neuropathy Screening Instrument (MNSI) and glycemic control and incident LEA during the clinical trial and subsequent follow-up. RESULTS: 9,746 patients were followed for a mean of 7.9 +/-3.1 (median 8.9) years after randomization. Ninety-eight (1%) participants underwent an incident LEA during the trial or post-trial follow-up period. Baseline demographics and traditional risk factors were examined by incident amputation status. Multivariable models revealed that abnormal 10 gm filament test (HR 4.50, 95% CI 2.92-6.95, P < 0.0001), presence of ulceration (HR 4.22, 95% CI 1.65-10.8, P = 0.0004), abnormal appearance on foot examination (HR 4.75, 95% CI 2.30-9.83, P < 0.0001), and mean postrandomization HbA1c (HR 1.65, 95% CI 1.35-2.00, P < 0.0001) were strongly predictive of LEA when accounting for other common risk factors for amputation. CONCLUSIONS: In this post hoc analysis of a large randomized controlled population of diabetic patients, we found that components of the MNSI score including presence of ulceration, abnormal appearance of the foot, and 10 gm filament monofilament scoring were strongly predictive of LEA. This adds a valuable clinical tool in the risk stratification of diabetic patients for LEA.

The Effects of Case Timing and Care Team Composition on Hospital Operating Room Costs for Endovascular Procedures.

BACKGROUND: The contemporary healthcare environment is complex with mounting pressures to perform greater procedural volumes with less support staff to minimize costs and maximize efficiency. This report details an analysis of routine endovascular procedures performed with dedicated vascular support staff during daytime hours compared to similar cases performed after hours with general operating room staff. METHODS: All lower extremity endovascular cases over a 37-month period were identified using Current Procedural Terminology codes from a query of our institutional database. Emergent/urgent cases and cases with associated open surgical procedures were excluded. Cases were divided according to the time of day and available clinical support structure according to procedure start time: specialty-specific daytime (SS) and general staff after hours for all others (AH). The resulting case list was examined by case type according to SS or AH designation and case types occurring disproportionately during either time frame were excluded to create a homogenous group of cases. Demographics, case specifics, and cost data were then obtained from the electronic health record and our enterprise cost data warehouse. Multivariable mixed linear modeling was used to examine component costs (i.e., anesthesia, supplies, etc.) and total costs controlling for a number of factors that could affect cost. RESULTS: Two hundred fifty-two routine endovascular-only procedures were examined in 232 patients (190 SS, 42 AH). No significant differences in procedure specifics were observed between the groups [number and location of access site(s), indication for procedure, type and number of interventions, etc.]. Multivariable analyses controlled for factors affecting costs. Costs associated with anesthesia (cost ratio 1.90, P = 0.001), operating room time costs (cost ratio 1.29, P = 0.03), and post anesthesia recovery (cost ratio 1.23, P = 0.004) were all significantly increased in AH cases compared to SS cases. The average total hospital cost for routine endovascular cases that performed AH was $8,095 compared to $5,636 for SS cases (cost ratio 1.44, P = 0.008). CONCLUSIONS: Performance of routine endovascular cases was associated with significantly less cost to the hospital system when performed by SS teams during regular hospital hours with a ∼30% increase in total cost associated with AH cases. In the current healthcare environment, investments in SS teams and process improvements are likely to be cost effective.

Rhodoliths holobionts in a changing ocean: host-microbes interactions mediate coralline algae resilience under ocean acidification.

BACKGROUND: Life in the ocean will increasingly have to contend with a complex matrix of concurrent shifts in environmental properties that impact their physiology and control their life histories. Rhodoliths are coralline red algae (Corallinales, Rhodophyta) that are photosynthesizers, calcifiers, and ecosystem engineers and therefore represent important targets for ocean acidification (OA) research. Here, we exposed live rhodoliths to near-future OA conditions to investigate responses in their photosynthetic capacity, calcium carbonate production, and associated microbiome using carbon uptake, decalcification assays, and whole genome shotgun sequencing metagenomic analysis, respectively. The results from our live rhodolith assays were compared to similar manipulations on dead rhodolith (calcareous skeleton) biofilms and water column microbial communities, thereby enabling the assessment of host-microbiome interaction under climate-driven environmental perturbations. RESULTS: Under high pCO2 conditions, live rhodoliths exhibited positive physiological responses, i.e. increased photosynthetic activity, and no calcium carbonate biomass loss over time. Further, whereas the microbiome associated with live rhodoliths remained stable and resembled a healthy holobiont, the microbial community associated with the water column changed after exposure to elevated pCO2. CONCLUSIONS: Our results suggest that a tightly regulated microbial-host interaction, as evidenced by the stability of the rhodolith microbiome recorded here under OA-like conditions, is important for host resilience to environmental stress. This study extends the scarce comprehension of microbes associated with rhodolith beds and their reaction to increased pCO2, providing a more comprehensive approach to OA studies by assessing the host holobiont.

Grip strength measurement for frailty assessment in patients with vascular disease and associations with comorbidity, cardiac risk, and sarcopenia.

OBJECTIVE: Frailty is associated with adverse events, length of stay, and nonhome discharge after vascular surgery. Frailty measures based on walking-based tests may be impractical or invalid for patients with walking impairment from symptoms or sequelae of vascular disease. We hypothesized that grip strength is associated with frailty, comorbidity, and cardiac risk among patients with vascular disease. METHODS: Dominant hand grip strength was measured during ambulatory clinic visits among patients with vascular disease (abdominal aortic aneurysm [AAA], carotid stenosis, and peripheral artery disease [PAD]). Frailty prevalence was defined on the basis of the 20th percentile of community-dwelling population estimates adjusted for age, gender, and body mass index. Associations between grip strength, Charlson Comorbidity Index (CCI), Revised Cardiac Risk Index (RCRI), and sarcopenia (based on total psoas area for patients with cross-sectional abdominal imaging) were evaluated using linear and logistic regression. RESULTS: Grip strength was measured in 311 participants; all had sufficient data for CCI calculation, 217 (69.8%) had sufficient data for RCRI, and 88 (28.3%) had cross-sectional imaging permitting psoas measurement. Eighty-six participants (27.7%) were categorized as frail on the basis of grip strength. Frailty was associated with CCI (odds ratio, 1.86; 95% confidence interval, 1.34-2.57; P = .0002) in the multivariable model. Frail participants also had a higher average number of RCRI components vs nonfrail patients (mean ± standard deviation, 1.8 ± 0.8 for frail vs 1.5 ± 0.7 for nonfrail; P = .018); frailty was also associated with RCRI in the adjusted multivariable model (odds ratio, 1.75; 95% confidence interval, 1.16-2.64; P = .008). Total psoas area was lower among patients categorized as frail vs nonfrail on the basis of grip strength (21.0 ± 6.6 vs 25.4 ± 7.4; P = .010). Each 10 cm2 increase in psoas area was associated with a 5.7 kg increase in grip strength in a multivariable model adjusting for age and gender (P < .0001). Adjusted least squares mean psoas diameter estimates were 25.5 ± 1.1 cm2 for participants with AAA, 26.7 ± 2.0 cm2 for participants with carotid stenosis, and 22.7 ± 0.8 cm2 for participants with PAD (P = .053 for PAD vs AAA; P = .057 for PAD vs carotid stenosis; and P = .564 for AAA vs carotid stenosis). CONCLUSIONS: Grip strength is useful for identifying frailty among patients with vascular disease. Frail status based on grip strength is associated with comorbidity, cardiac risk, and sarcopenia in this population. These findings suggest that grip strength may have utility as a simple and inexpensive risk screening tool that is easily implemented in ambulatory clinics, avoids the need for imaging, and overcomes possible limitations of walking-based measures. Lower mean psoas diameters among patients with PAD vs other diagnoses may warrant consideration of specific approaches to morphomic analysis.

Superior Lower Extremity Vein Graft Bypass Patency among Married Patients with Peripheral Artery Disease.

BACKGROUND: Outcome disparities associated with lower extremity bypass (LEB) for peripheral artery disease (PAD) have been identified but are poorly understood. Marital status may affect outcomes through factors related to health risk behaviors, adherence, and access to care but has not been characterized as a predictor of surgical outcomes and is often omitted from administrative data sets. We evaluated associations between marital status and vein graft patency following LEB using multivariable models adjusting for established risk factors. METHODS: Consecutive patients undergoing autogenous LEB for PAD were identified and analyzed. Survival analysis and Cox proportional hazards models were used to evaluate patency stratified by marital status (married versus single, divorced, or widow[er]) adjusting for demographic, comorbidity, and anatomic factors in multivariable models. RESULTS: Seventy-three participants who underwent 79 autogenous vein LEB had complete data and were analyzed. Forty-three patients (58.9%) were married, and 30 (41.1%) were unmarried. Compared with unmarried patients, married patients were older at the time of their bypass procedure (67.3 ± 10.8 years vs. 62.2 ± 10.6 years; P = 0.05). Married patients also had a lower prevalence of female gender (11.6% vs. 33.3%; P = 0.02). Diabetes, hypertension, hyperlipidemia, and smoking were common among both married and unmarried patients. Minimum great saphenous vein conduit diameters were larger in married versus unmarried patients (2.82 ± 0.57 mm vs. 2.52 ± 0.65 mm; P = 0.04). Twenty-four-month primary patency was 66% for married versus 38% for unmarried patients. In a multivariable proportional hazards model adjusting for proximal and distal graft inflow/outflow, medications, gender, age, race, smoking, diabetes, and minimum vein graft diameter, married status was associated with superior primary patency (hazard ratio [HR] = 0.33; 95% confidence limits [0.11, 0.99]; P = 0.05); other predictive covariates included preoperative antiplatelet therapy (HR = 0.27; 95% confidence limits [0.10, 0.74]; P = 0.01) and diabetes (HR = 2.56; 95% confidence limits [0.93-7.04]; P = 0.07). CONCLUSIONS: Marital status is associated with vein graft patency following LEB. Further investigation into the mechanistic explanation for improved patency among married patients may provide insight into social or behavioral factors influencing other disparities associated with LEB outcomes.

Gender-specific Differences in Great Saphenous Vein Conduit. A Link to Lower Extremity Bypass Outcomes Disparities?

BACKGROUND: Inferior lower extremity bypass (LEB) outcomes have been reported among women with peripheral arterial disease (PAD), but the mechanisms responsible for this disparity are unknown. Great saphenous vein (GSV) is considered the conduit of choice for LEB; GSV diameter is associated with graft patency and therefore is often used as a criterion for suitability for use as bypass conduit. We hypothesized that gender-based differences in GSV may contribute to LEB outcomes disparities. To explore this hypothesis, we performed a gender-based analysis of GSV anatomic characteristics among patients with PAD who were studied with duplex ultrasound vein mapping during evaluation for LEB. METHODS: Consecutive patients undergoing ultrasound vein mapping for planned LEB were analyzed. Minimum above- and below-knee GSV diameters were obtained in addition to demographic, procedural, and clinical data. Associations between gender and GSV diameter were evaluated using multivariate mixed models adjusting for anatomic location and within-patient correlation. RESULTS: One hundred five patients were analyzed. Mean patient age was 65 ± 11 years, 25% were women, and 78% were white. Mixed model estimates of minimum GSV diameters were 3.14 ± 0.09 mm above knee and 2.74 ± 0.09 below knee for men versus 3.23 ± 0.14 above-knee and 2.49 ± 0.14 below knee for women. A gender-based interaction between anatomic location and GSV diameter was identified, with women having a greater difference between above- and below-knee GSV diameters (or taper; mean difference of 0.73 ± 0.12 vs. 0.41 ± 0.17 mm; P = 0.017). CONCLUSIONS: GSV taper (difference between above- and below-knee diameters) is greater in women and may contribute to inferior patency after LEB with vein conduit, particularly for below-knee target vessels. Further research is necessary to evaluate specific hemodynamic effects of graft taper and links with other clinical endpoints. In addition to minimum diameter, vein graft taper may warrant consideration when planning LEB.

Endovascular Treatment of Chronic Mesenteric Ischemia in the Setting of Occlusive Superior Mesenteric Artery Lesions.

BACKGROUND: Endovascular intervention is considered the first-line treatment for chronic mesenteric ischemia (CMI) when feasible. Two-vessel revascularization is most definitive when celiac (CA) and superior mesenteric arteries (SMA) are diseased, but single-vessel intervention may be performed in patients with 2-vessel disease due to anatomic/technical factors. We evaluated anatomic predictors of clinical outcomes associated with endovascular treatment of CMI among patients with occlusive SMA lesions. METHODS: Patients with CMI treated with endovascular revascularization over 10 years were identified. Patients with SMA occlusions were selected for analysis. Between-group comparisons based on inclusion of an SMA revascularization were evaluated using t-test and chi-squared test. Freedom from symptomatic recurrence or repeat intervention was analyzed using proportional hazards regression. RESULTS: Fifty-four patients with CMI were analyzed. Sixteen (29.6%) patients had CA-only intervention, and 38 (70.4%) patients had SMA revascularization with or without CA intervention. No significant differences in demographics or comorbidity were identified between groups. In the CA-only intervention group, 8 of the 16 (50%) patients developed symptomatic recurrence compared with 8 of the 31 (21.1%) patients whose intervention included the SMA. Patients treated without SMA intervention also had decreased freedom from both symptomatic recurrence (hazard ratio [HR] 3.2, 95% confidence interval [CI] 1.2-8.6, P = 0.016) and repeat intervention (HR 5.5, 95% CI 1.8-16.3, P = 0.001). CONCLUSIONS: Among patients with CMI and occlusive SMA lesions, SMA revascularization appears to be the key determinant for symptomatic outcomes and repeat intervention. Patient counseling should include potential future need for surgical revascularization if endovascular SMA treatment cannot be accomplished.

Microvasculature and incident atrioventricular conduction abnormalities in the Multi-Ethnic Study of Atherosclerosis (MESA).

Abnormalities of the microvasculature are linked to major cardiac events, but their role in the development of atrioventricular conduction abnormalities (AVCA) is unknown. We examined the association between central retinal arteriolar equivalent (CRAE), a measure of the microvasculature, and incident AVCA. This analysis included 3975 participants free of AVCA at baseline from the Multi-Ethnic Study of Atherosclerosis (MESA). Incident AVCA was defined as a composite of new heart rate-adjusted PR interval ⩾ 200 ms (first-degree AV block) and advanced block (second-degree or complete AV block) detected from the MESA exam 5 electrocardiogram (ECG). CRAE was measured from retinal photographs at exam 2. Both ECGs and retinal photographs were collected using standardized methods and read and graded at central core labs. Incident AVCA were present in 7.4% (n=290) of the participants, of which 94% were first-degree AV block. Incident AVCA were increasingly more common in participants with narrower CRAE (4.6% in Q4, 6.4% in Q3, 7.0% in Q2 and 10.8% in Q1, p-value for trend < 0.0001). The socio-demographic and cardiovascular disease risk-adjusted odds of incident AVCA in the Q1 group (the group with the narrowest retinal arteriolar diameter) was nearly twice the odds in the Q4 group (OR: 1.68, 95% CI: 1.15-2.51). This association remained significant after adjustment for major ECG abnormalities and incident cardiovascular disease (Q1 vs Q4, OR: 1.65, 95% CI: 1.01-2.71). In conclusion, narrower retinal arteriolar caliber is associated with development of new AV conduction abnormalities.

Increased prevalence of preeclampsia among women undergoing procedural intervention for renal artery fibromuscular dysplasia.

BACKGROUND: Renal artery fibromuscular dysplasia (RA-FMD) has a higher prevalence among women and a presumed hormonal etiology. Although preeclampsia has a clinical presentation similar to symptomatic RA-FMD and occurs exclusively in women, associations between these 2 diseases have not been characterized. To explore epidemiologic associations between RA-FMD and preeclampsia, we administered a validated screening instrument for preeclampsia to a cohort of women with a history of pregnancy who had previously been treated with procedural intervention for symptomatic RA stenosis. METHODS: Women with a history of pregnancy who had previously undergone procedural intervention (including angioplasty and/or bypass) for symptomatic RA stenosis were identified from a prospectively maintained operative registry and screened for remote history of preeclampsia using a validated survey instrument. Univariable associations between RA-FMD and preeclampsia among participants with a history of pregnancy were evaluated using t-tests for continuous factors and chi-squared tests for dichotomous factors. Multivariable associations were evaluated using logistic regression models. RESULTS: A total of 144 women were identified who met the study inclusion criteria, including 94 with atherosclerotic RA stenosis and 50 with RA-FMD. Sixty-nine patients were contacted, 59 consented to participate, and 52 had a history of pregnancy (and therefore were at risk for preeclampsia). Participants completed the survey instrument at a mean of 7.1 ± 3.1 vs. 6.9 ± 3.6 years after RA procedural intervention, respectively. Survey responses indicated a history of preeclampsia in 19/52 (36.5%) of participants overall, including 14/27 (51.9%) with RA-FMD versus 5/20 (20.0%) with RA atherosclerosis (P = 0.02). Preeclampsia remained associated with FMD in a multivariable model adjusting for smoking status, age at time of surgery, and estimated glomerular filtration rate (odds ratio [OR] 9.51, 95% confidence interval [CI] 1.49-60.6, P = 0.017); age at the time of surgery (OR 2.78, 95% CI 1.04-7.42, P = 0.041) and estimated glomerular filtration rate (OR 3.31, 95% CI 1.29-8.52, P = 0.013) were also associated with FMD in the multivariable model. CONCLUSIONS: Women with a history of procedural intervention for symptomatic RA stenosis have an overall prevalence of preeclampsia which greatly exceeds that expected in the general population, and our results suggest that preeclampsia is specifically associated with RA-FMD. Further investigation is needed to characterize the mechanistic relationships between FMD and preeclampsia and may have potential to decrease related cardiovascular morbidity and mortality.

Loss of the hyaluronan receptor RHAMM prevents constrictive artery wall remodeling.

OBJECTIVE: Constrictive extracellular matrix (ECM) remodeling contributes significantly to restenosis after arterial reconstruction, but its molecular regulation is poorly defined. Hyaluronan (HA) accumulates within ECM at sites of injury where it is thought to facilitate smooth muscle cell (SMC) trafficking and collagen remodeling analogous to its role in cutaneous wound healing. SMC receptors for HA include receptor for hyaluronan-mediated motility (RHAMM), which mediates HA-induced migration. We hypothesized RHAMM would also mediate SMC-matrix interactions to alter the extent of constrictive remodeling. METHODS: We studied the role of RHAMM in SMC attachment to collagen, migration, and contraction of collagen gels using blocking antibodies and SMC from RHAMM -/- knockout mice. We then determined the role of RHAMM in constrictive artery wall remodeling by comparing changes in wall geometry in RHAMM -/- vs wild-type (WT) RHAMM +/+ controls 1 month after carotid ligation. RESULTS: HA increased SMC attachment to collagen-coated plates, but blocking RHAMM reduced adhesion (P = .025). RHAMM -/- SMC also demonstrated reduced adhesion (% adherent: 36.1 ± 2.2 vs 76.3 ± 1.9; P < .05). SMC contraction of collagen gels was enhanced by HA and further increased by RHAMM blockade (P < .01) or knockout (gel diameter, mm: RHAMM -/-, 6.7 ± 0.1 vs WT 9.8 ± 0.1; P < .01). RHAMM promoted constrictive remodeling in vivo as carotid artery size was significantly larger in knockout mice 1 month after ligation. Neointimal thickening, however, was not affected in RHAMM -/- (P = NS vs WT), but lumen size was significantly larger (lumen area, µm(2): 52.4 ± 1.4 × 10(3) vs 10.4 ± 1.8 × 10(3); P = .01) because artery size constricted less (external elastic lamina area, µm(2): RHAMM -/-, 92.4 ± 4.7 × 10(3) vs WT, 51.3 ± 5.9 × 10(3); P = .015). Adventitial thickening and collagen deposition were also more extensive in ligated RHAMM -/- carotids (adventitial thickness, µm: 218 ± 12.2 vs 109 ± 7.9; P = .01). CONCLUSIONS: HA activation of RHAMM significantly impacts SMC-ECM adhesive interactions and contributes to constrictive artery wall remodeling in mice. Strategies to block RHAMM at sites of vessel injury may prove useful in the prevention of clinical restenosis.

Anatomic characteristics and natural history of renal artery aneurysms during longitudinal imaging surveillance.

OBJECTIVE: Renal artery aneurysms (RAAs) are uncommon, and rates of growth and rupture are unknown. Limited evidence therefore exists to guide clinical management of RAAs, particularly small aneurysms that are asymptomatic. To further characterize the natural history of RAAs, we studied anatomic characteristics and changes in diameter during imaging surveillance. METHODS: Patients evaluated for native RAAs at a single institution during a 5-year period (July 2008 to July 2013) were identified and analyzed retrospectively. Patients with two or more cross-sectional imaging studies (computed tomography or magnetic resonance imaging) more than 1 month apart were included. Demographic and clinical data were collected from medical records, and anatomic data (including aneurysm diameter, calcification, and location) were obtained from electronic images. Changes in RAA diameters over time were evaluated by plots and Wilcoxon signed rank tests. RESULTS: Sixty-eight RAAs in 55 patients were analyzed. Median follow-up was 19.4 months (interquartile range, 11.2-49.0 months). Mean age at presentation was 61.8 ± 9.8 years, and 73% of patients were women. Hypertension was prevalent among 73% of patients. Multiple RAAs were present in 18% of patients, and 24% also had arterial aneurysms of other splanchnic or iliac vessels. The majority of RAAs were calcified and located at the main renal artery bifurcation. Mean initial aneurysm diameter was 16.0 ± 6.4 mm. Median annualized growth rate was 0.06 mm (interquartile range, -0.07 to 0.33 mm; P = .11). No RAA ruptures or acute symptoms occurred during surveillance, and 10.3% of RAAs were repaired electively. CONCLUSIONS: Risk of short-term RAA growth or rupture was low. These findings suggest that annual (or less frequent) imaging surveillance is safe in the majority of patients and do not support pre-emptive repair of asymptomatic, small-diameter RAAs.

Influence of computed tomography angiography reconstruction software on anatomic measurements and endograft component selection for endovascular abdominal aortic aneurysm repair.

OBJECTIVE: Three-dimensional (3D) centerline reconstruction of computed tomography angiography (CTA) images permits detailed anatomic characterization of abdominal aortic aneurysms and facilitates planning of endovascular repair. Although several programs for 3D CTA reconstruction and measurement are available, direct comparisons have not been published, and reliability between software platforms has not been characterized. We evaluated agreement between anatomic measurements obtained from 3D CTA reconstructions using three commercially available software programs and characterized concordance between the programs for endograft component selection. METHODS: Images from 92 CTA studies performed before abdominal aortic aneurysm repair were reconstructed and measured using three different software programs: independent reconstruction with proprietary software (Preview; M2S Inc, Lebanon, NH), surgeon-based reconstruction with proprietary software (AquariusNet Thin Client; TeraRecon Inc, San Mateo, Calif), and surgeon-based reconstruction with open-source software (Osirix MD; Pixmeo, Geneva, Switzerland). Agreement between outer wall diameter and length measurements obtained from centerline reconstructions created with each program was evaluated using scatter plots, intraclass correlation coefficients, and Bland-Altman plots. Concordance between aortic and iliac endograft component diameters selected from measurements with each program based on published instructions for use was examined using weighted κ statistics. RESULTS: Diameter measurements were generally similar between programs. Mean diameters at all locations were within ≤ 1 mm of one another, and mean length measurements were within ≤ 10 mm of one another for all pairwise comparisons. Intraclass correlations coefficients between programs for diameter measurements were comparable between programs (≥ 0.82 for all diameter comparisons and ≥ 0.88 for all length comparisons) and indicated good correlation. Pair-wise comparisons indicated similar rates of identical and adjacent size endograft component selection without an obvious trend toward superior agreement for any two programs. Rates of identical proximal endograft diameter selection ranged from 46% to 59%, whereas 89% to 100% of proximal endograft diameters selected between programs were within one adjacent (smaller or larger) size of each other. For iliac endograft selection, rates of identical component diameter selection between programs ranged from 36% to 69%, and 58% to 99% of selected iliac endograft diameters were within one adjacent size. CONCLUSIONS: Outer wall diameter and centerline length measurements obtained from 3D CTA reconstructions demonstrated good correlation between imaging analysis software programs, and graft diameter selections based on these measurements were reasonably similar. Comparable 3D CTA reconstruction measurements can be generated from independent and surgeon-based approaches using proprietary and open-source software, and the selection of a method to interpret images for endograft planning can be individualized according to operator experience and available resources while retaining sufficient accuracy.

Anatomic findings and outcomes associated with upper extremity arteriography and selective thrombolysis for acute finger ischemia.

OBJECTIVE: Limited evidence exists to guide clinical management of acute finger ischemia (AFI). To further inform diagnostic evaluation and decision making, we evaluated anatomic findings, procedural management, and amputation-free survival in an institutional cohort of patients with AFI. METHODS: Consecutive patients undergoing transfemoral upper extremity angiography for AFI were identified. Clinical, laboratory, and procedural data were collected retrospectively from medical records, and arteriograms were reviewed to characterize anatomic findings. Telephone interviews were used to determine long-term outcomes, and additional symptomatic assessments (Symptom Severity and Functional Status scale, the Cold Sensitivity Severity scale, and the McGill Pain Severity Scale) were available in a subgroup of patients. Outcomes included anatomic findings, use of thrombolysis, complications, and amputation-free survival. Descriptive statistics and survival analysis were used to evaluate results. RESULTS: Thirty-five patients (54% women) were analyzed with a median follow-up of 13.7 months. Symptom duration at time of presentation ranged from 1 to 28 days, and seven patients had tissue loss or gangrene, or both. Mean age was 47.7 ± 12.2 years. Baseline characteristics included smoking in 22 (65%), connective tissue disorder in 11 (31%), and history of repetitive hand trauma in 10 (29%). The most frequent anatomic location of arterial pathology identified during angiography was distal to the wrist (n = 32), including eight ulnar/radial aneurysms; upper arm (n = 3) and forearm (n = 8) lesions were less common. Sixteen patients were treated with catheter-directed thrombolysis, of which eight (50%) had interval anatomic improvement on repeat angiography. Procedure-related adverse events associated with angiography included bleeding (n = 3) and pseudoaneurysm (n = 1). Eleven of 35 patients had subsequent surgical revascularization at a median of 15 days after angiography. Estimated (standard error) amputation-free survival was 0.88 (0.07) at 1 month and 0.84 (0.08) at 6 months among patients without tissue loss or gangrene. Estimated 60-day amputation-free survival was 0.84 (standard error, 0.08). Overall amputation-free survival was similar between patients managed with vs without thrombolysis (P = .61), but subgroup analysis of those patients without tissue loss or gangrene at the time of presentation revealed a trend toward improved amputation-free survival with use of thrombolysis, with 60-day amputation-free survival of 0.92 vs 0.75 (P = .12). Persistent late symptoms were present in 17 patients (48.6%) at the last follow-up and were generally characterized as mild by functional and pain scale assessments. CONCLUSIONS: Angiography performed for AFI frequently identifies distal occlusive disease, and catheter-directed thrombolysis may expand revascularization options in select patients.