Longer Operative Time for Lower Extremity Bypass Surgery is Associated With Inferior Outcomes.

INTRODUCTION: This study aims to assess the association of operative time with the postoperative length of stay and unplanned return to the operating room in patients undergoing femoral to below knee popliteal bypasses, stratified by autologous vein graft or polytetrafluoroethylene (PTFE). MATERIALS AND METHODS: A retrospective analysis of vascular quality initiative database (2003-2021). The selected patients were grouped into the following: vein bypass (group I) and PTFE (group II) patients. Each group was further stratified by a median split of operative time (i.e., 210 min for autologous vein and 155 min for PTFE) to study the outcomes. The outcomes were assessed by univariate and multivariate approach. RESULTS: Of the 10,902 patients studied, 3570 (32.7%) were in the autologous vein group, while 7332 (67.3%) were in the PTFE group. Univariate analysis revealed autologous vein and PTFE graft recipients that had increased operative times were associated with a longer mean postoperative length of stay and a higher incidence of all-cause return to the operating room. In PTFE group, patients with prolonged operative times were also found to be associated with higher incidence of major amputation, surgical site infection, and cardiovascular events, along with loss of primary patency within a year. CONCLUSIONS: For patients undergoing femoral to below knee popliteal bypasses using an autologous vein or PTFE, longer operative times were associated with inferior outcomes. Mortality was not found to be associated with prolonged operative time.

The implications of surgeon case volume and hospital volume on outcomes of aortobifemoral bypasses in obese patients.

BACKGROUND: Aortobifemoral (ABF) bypass is the gold standard for treating symptomatic aortoiliac occlusive disease. In the era of heightened interest in the length of stay (LOS) for surgical patients, this study aims to investigate the association of obesity with postoperative outcomes at the patient, hospital, and at surgeon levels. METHODS: This study used the Society of Vascular Surgery Vascular Quality Initiative suprainguinal bypass database from 2003 to 2021. The selected study cohort was divided into obese patients (body mass index ≥30) (group I) and nonobese patients (body mass index <30) (group II). Primary outcomes of the study included mortality, operative time, and postoperative LOS. Univariate and multivariate logistic regression analyses were performed to study the outcomes of ABF bypass in group I. Operative time and postoperative LOS were transformed into binary values by median split for regression analysis. A P value of .05 or less was deemed statistically significant in all the analyses of this study. RESULTS: The study cohort consisted of 5392 patients. In this population, 1093 were obese (group I) and 4299 were nonobese (group II). Group I was found to have more females with higher rates of comorbid conditions, including hypertension, diabetes mellitus, and congestive heart failure. Patients in group I had increased odds of prolonged operative time (≥250 minutes) and an increased LOS (≥6 days). Patients in this group also had a higher chance of intraoperative blood loss, prolonged intubation, and required vasopressors postoperatively. There was also an increased odds of postoperative decline in renal function in the obese population. Patients with prior history of coronary artery disease, hypertension, diabetes mellitus, and urgent or emergent procedures were found to be risk factors for a LOS of more than 6 days in obese patients. An increase in the surgeons' case volume was associated with lesser odds of an operative time of 250 minutes or more; however, no significant impact was found on postoperative LOS. Hospitals where 25% or more of ABF bypasses were performed on obese patients were also more likely to have LOS of less than 6 days after ABF operations, compared with hospitals where less than 25% of ABF bypasses were performed on obese patients. Patients undergoing ABF for chronic limb-threatening ischemia or acute limb ischemia had a longer LOS and increased operative times. CONCLUSIONS: ABF bypass in obese patients is associated with prolonged operative times and a longer LOS than in nonobese patients. Obese patients operated by surgeons with more cases of ABF bypasses have shorter operative times. A hospital's increasing proportion of obese patients was related to a decreased LOS. These findings support the known volume-outcome relationship that, with a higher surgeon case volume and increased proportion of obese patients in a hospital, there is an improvement in outcomes of obese patients undergoing ABF bypass.

Patients from distressed communities are more likely to be symptomatic at endovascular aneurysm repair and have an increased risk of being lost to long-term follow-up.

BACKGROUND: Endovascular aortic aneurysm repair (EVAR) has become the preferred modality to repair abdominal aortic aneurysms (AAAs). However, the effect of the distressed communities index (DCI) on the outcomes of EVAR is still unknown. In the present study, we investigated the effect of DCI on the postoperative outcomes after EVAR. METHODS: The Society for Vascular Surgery Vascular Quality Initiative database was used for the present study. Patients who had undergone EVAR from 2003 to 2021 were selected for analysis. The study cohort was divided into two groups according to their DCI score. Patients with DCI scores ranging from 61 to 100 were assigned to group I (DCI >60), and those with DCI scores ranging from 0 to 60 were assigned to group II (DCI ≤60). The primary outcomes included the 30-day and 1-year mortality and major adverse cardiovascular events at 30 days. Regression analyses were performed to study the postoperative outcomes. P values ≤ .05 were deemed statistically significant for all analyses in the present study. RESULTS: A total of 60,972 patients (19.5% female; 80.5% male) had undergone EVAR from 2003 to 2021. Of these patients, 18,549 were in group I (30.4%) and 42,423 in group II (69.6%). The mean age of the study cohort was 73 ± 8.9 years. Group I tended to be younger (mean age, 72.6 vs 73.7 years), underweight (3.5% vs 2.5%), and African American (10.8% vs 3.5%) and were more likely to have Medicaid insurance (3.6% vs 1.9%; P < .05 for all). Group I had had more smokers (87.3% vs 85.3%), a higher rate of comorbidities, including hypertension (84.5% vs 82.9%), diabetes (21.7% vs 19.7%), coronary artery disease (30.3% vs 28.6%), chronic obstructive pulmonary disease (36.9% vs 31.8%), and moderate to severe congestive heart failure (2.6% vs 2%; P < .05 for all). The group I patients were more likely to undergo EVAR for symptomatic AAAs (11.1% vs 7.9%; P < .001; adjusted odds ratio [aOR], 1.25; 95% confidence interval [CI], 1.15-1.37; P < .001) with a higher risk of mortality at 30 days (aOR, 3.98; 95% CI, 2.23-5.44; P < .001) and 1 year (aOR, 1.74; 95% CI, 1.43-2.13; P < .001). A higher risk of being lost to follow-up (28.9% vs 26.3%; P < .001) was also observed in group I. CONCLUSIONS: Patients from distressed communities who require EVAR tended to have multiple comorbidities. These patients were also more likely to be treated for symptomatic AAAs, with a higher risk of mortality. An increased incidence of lost to long-term follow-up was also observed for this population. Surgeons and healthcare systems should consider these outcomes and institute patient-centered approaches to ensure equitable healthcare.

Fenestrated endovascular abdominal aortic aneurysm repair in octogenarians is associated with higher mortality and an increased incidence of nonhome discharge.

OBJECTIVE: Fenestrated endovascular abdominal aortic aneurysm repair (FEVAR) has been increasingly becoming the endovascular treatment of choice for patients with juxtarenal abdominal aortic aneurysms with an infrarenal neck, not suitable for traditional endovascular abdominal aortic aneurysm repair. Older patients are at a high risk of developing complications after elective procedures. A review of the literature showed mixed results for FEVAR in the elderly patient population. In the present study, we investigated the occurrence of mortality (both short and long term), discharge destination, and other postoperative outcomes in the octogenarian population who had undergone FEVAR for the management of abdominal aortic aneurysms in a large, national surgical database. METHODS: A retrospective analysis of patients who had undergone FEVAR in the Society for Vascular Surgery Vascular Quality Initiative database was performed from July 2010 to June 2019. The study cohort excluded patients aged <18 years and concomitant procedures for snorkeling of visceral branches of the aorta. The final selected cohort was divided into two patient groups: group I, patients aged <80 years (nonoctogenarians); and group II, patients aged ≥80 years (octogenarians). The primary outcomes were mortality at 30 days (short term), 6 months, and 1 year (long term) and the discharge destination. The secondary outcomes included postoperative length of stay, intensive care unit stay, postoperative major cardiac events, and the need for intervention. Computation of models to measure the outcomes and identify the risk factors contributing to mortality at 30 days and discharge to a nonhome destination was performed using multiple logistic regression analyses. Cox proportional hazards regression analysis was performed to study the long-term mortality in the patient groups. RESULTS: A total of 5507 patients had undergone FEVAR in the 9-year period in the Society for Vascular Surgery Vascular Quality Initiative database (group I, nonoctogenarians, n = 4424 [80.3%]; group II, octogenarians, n = 1156 [19.7%]). Octogenarians were more likely to be women, white, Medicare insured, and hypertensive. This group also had lower rates of former or current smokers, a lower glomerular filtration rate, a lower incidence of late-stage chronic kidney disease, and an aneurysm diameter >5.5 cm. Greater estimated blood loss and longer procedures were also noted in the octogenarian group compared with the nonoctogenarian group. Multiple logistic regression analysis showed that octogenarians had had greater mortality at 30 days (7.3%; adjusted odds ratio [aOR], 1.21; 95% confidence interval [CI], 1.0-1.45; P = .044), 6 months (13.7%; aOR, 1.52; 95% CI, 1.24-1.81; P < .001), and 1 year (17.5%; aOR, 1.67; 95% CI, 1.34-2.07; P < .001). The present analysis to measure the discharge destination showed that octogenarians had a greater risk of discharge to nonhome destinations (26.7%; aOR, 1.50; 95% CI, 1.24-1.81; P < .001). Octogenarians had a lower risk of ≥2 days of an intensive care unit stay (aOR, 0.76; 95% CI, 0.67-0.91; P < .001) but a greater risk of experiencing dysrhythmia (10.1%; aOR, 1.32; 95% CI, 1.01-7.1; P = .036) following the procedure compared with the nonoctogenarians. CONCLUSIONS: In our retrospective analysis of a large, national surgical database, we found that of the patients undergoing FEVAR to manage juxtarenal abdominal aortic aneurysms, octogenarians had greater mortality and a greater risk of being discharged to nonhome locations compared with nonoctogenarians.

A prospective community engagement initiative to improve clinical research participation in patients with peripheral artery disease.

OBJECTIVE: Patients diagnosed with peripheral artery disease are difficult to recruit into clinical trials. However, there is currently no high-quality, patient-centered information explaining why peripheral artery disease patients choose to participate or not participate in clinical research studies. METHODS: The current study was a prospective community engagement initiative that specifically asked patients with and without peripheral artery disease: (1) what motivates them to participate in clinical research studies, (2) their willingness to participate in different research procedures, (3) the barriers to participation, (4) preferences about study design, and (5) demographic and disease-related factors influencing participation. Data were gathered through focus groups (n = 19, participants aged 55-79 years) and mailed questionnaires (n = 438, respondents aged 18-85 years). RESULTS: More than half of the respondents stated that they would be willing to participate in a study during evening or weekend time slots. Peripheral artery disease patients (n = 45) were more willing than those without peripheral artery disease (n = 360) to participate in drug infusion studies (48% versus 18%, p < 0.001) and trials of investigational drugs (44% versus 21%, p < 0.001). Motivating factors and barriers to participation were largely consistent with previous studies. CONCLUSION: Adults in our geographic region are interested in participating in clinical research studies related to their health; they would like their doctor to tell them what studies they qualify for and they prefer to receive a one-page advertisement that has color pictures of the research procedures. Peripheral artery disease patients are more willing than those without peripheral artery disease to participate in drug infusion studies, trials of investigational drugs, microneurography, and spinal/epidural infusions.

Factors associated with symptomatic postoperative myocardial infarction after endovascular aneurysm repair.

OBJECTIVE: Endovascular aneurysm repair (EVAR) has now become the most common operation to treat abdominal aortic aneurysms (AAAs). One of the perceived benefits of EVAR over open AAA repair is reduced incidence of perioperative cardiac complications and mortality. The purpose of this study was to determine risk factors associated with postoperative myocardial infarction (POMI) in patients who have undergone EVAR. METHODS: Data were obtained from the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database for the years 2012 to 2015 in the Participant Use Data File. All patients in the database who underwent EVAR during this time were identified. These patients were then divided into two groups: those with POMI and those without. Bivariate analysis was done for preoperative, intraoperative, and postoperative risk factors, followed by multivariable analysis to determine associations of independent variables with POMI. A risk prediction model for POMI was created to accurately predict incidence of POMI after EVAR. RESULTS: A total of 7702 patients (81.3% male, 18.7% female) were identified who underwent EVAR from 2011 to 2015. Of these patients, 110 (1.4%) had POMI and 7592 (98.6%) did not. Several risk factors were related to an increased risk of POMI, including dependent functional health status, need for lower extremity revascularization, longer operation time, and ruptured AAA (P < .05, all).On multivariable analysis, the following factors were found to have significant associations with POMI: return to operating room (odds ratio [OR], 1.84; confidence interval [CI], 1.10-3.09; P = .020), ruptured AAA (OR, 1.87; CI, 1.18-2.95; P = .008), pneumonia (OR, 1.94; CI, 1.01-3.73; P = .048), age >80 years (compared with <70 years; OR, 2.30; CI, 1.36-3.86; P = .002), unplanned intubation (OR, 4.07; CI, 2.31-7.18; P < .001), and length of hospital stay >6 days (OR, 8.43; CI, 4.75-14.94; P < .001). The risk prediction model showed that in the presence of all these risk factors, the incidence of POMI was 58.3%. The incidence of cardiac arrest and death was significantly higher for patients with POMI compared with patients without POMI (cardiac arrest, 11.9% vs 1.3%; death, 10.2% vs 1.1%). CONCLUSIONS: In patients who undergo EVAR, the risk of POMI is increased for those who are older, who present with a ruptured AAA, who have pneumonia, who have unplanned intubation, and who have prolonged hospital stay. Patients who suffer from POMI have higher risk of having cardiac arrest and death.

Peripheral revascularization attenuates the exercise pressor reflex and increases coronary exercise hyperemia in peripheral arterial disease.

Peripheral arterial disease (PAD) is associated with augmented blood pressure (BP) and impaired coronary blood flow responses to exercise, which may increase cardiovascular risk. We investigated the effects of leg revascularization on the BP and coronary blood flow responses to exercise in PAD. Seventeen PAD patients (11 men, 66 ± 2 yr) performed single-leg plantar flexion exercise 24 h before and 1 mo following leg revascularization. BP and heart rate (HR) were measured continuously, and rate pressure product (systolic BP × HR) was calculated as an index of myocardial oxygen demand. Coronary blood velocity was obtained by transthoracic Doppler echocardiography in 8/17 subjects. The mean BP response to plantar flexion exercise was attenuated by leg revascularization (pre-revascularization: 15 ± 4 vs. post-revascularization: 7 ± 3 mmHg, P = 0.025). The HR response to plantar flexion was also attenuated following leg revascularization (pre-revascularization: 9 ± 1 vs. post-revascularization: 6 ± 1 beats/min, P = 0.006). The change in coronary blood velocity with exercise was greater at the post-revascularization visit: 4 ± 1 vs. pre-revascularization: -1 ± 2 cm/s ( P = 0.038), even though the change in rate pressure product was not greater following revascularization in these subjects (pre-revascularization: 2,796 ± 871 vs. post-revascularization: 1,766 ± 378 mmHg·beats/min, P = 0.082). These data suggest that leg revascularization alters reflex control of BP, HR, and coronary blood flow in response to exercise in patients with PAD. NEW & NOTEWORTHY We found that peripheral revascularization procedures lowered exercise blood pressure and improved coronary blood flow in patients with peripheral arterial disease.

Blood pressure and calf muscle oxygen extraction during plantar flexion exercise in peripheral artery disease.

Peripheral artery disease (PAD) is an atherosclerotic vascular disease that affects 200 million people worldwide. Although PAD primarily affects large arteries, it is also associated with microvascular dysfunction, an exaggerated blood pressure (BP) response to exercise, and high cardiovascular mortality. We hypothesized that fatiguing plantar flexion exercise that evokes claudication elicits a greater reduction in skeletal muscle oxygenation (SmO2) and a higher rise in BP in PAD compared with age-matched healthy subjects, but low-intensity steady-state plantar flexion elicits similar responses between groups. In the first experiment, eight patients with PAD and eight healthy controls performed fatiguing plantar flexion exercise (from 0.5 to 7 kg for up to 14 min). In the second experiment, seven patients with PAD and seven healthy controls performed low-intensity plantar flexion exercise (2.0 kg for 14 min). BP, heart rate (HR), and SmO2 were measured continuously using near-infrared spectroscopy (NIRS). SmO2 is the ratio of oxygenated hemoglobin to total hemoglobin, expressed as a percent. At fatigue, patients with PAD had a greater increase in mean arterial BP (18 ± 2 vs. vs. 10 ± 2 mmHg, P = 0.029) and HR (14 ± 2 vs. 6 ± 2 beats/min, P = 0.033) and a greater reduction in SmO2 (-54 ± 10 vs. -12 ± 4%, P = 0.001). However, both groups had similar physiological responses to low-intensity, nonpainful plantar flexion exercise. These data suggest that patients with PAD have altered oxygen uptake and/or utilization during fatiguing exercise coincident with an augmented BP response.NEW & NOTEWORTHY In this laboratory study, patients with peripheral artery disease performed plantar flexion exercise in the supine posture until symptoms of claudication occurred. Relative to age- and sex-matched healthy subjects we found that patients had a higher blood pressure response, a higher heart rate response, and a greater reduction in skeletal muscle oxygenation as determined by near-infrared spectroscopy. Our data suggest that muscle ischemia contributes to the augmented exercise pressor reflex in peripheral artery disease.

Coronary Exercise Hyperemia Is Impaired in Patients with Peripheral Arterial Disease.

BACKGROUND: Peripheral arterial disease (PAD) is an atherosclerotic vascular disease that affects over 200 million people worldwide. The hallmark of PAD is ischemic leg pain and this condition is also associated with an augmented blood pressure response to exercise, impaired vascular function, and high risk of myocardial infarction and cardiovascular mortality. In this study, we tested the hypothesis that coronary exercise hyperemia is impaired in PAD. METHODS: Twelve patients with PAD and no overt coronary disease (65 ± 2 years, 7 men) and 15 healthy control subjects (64 ± 2 years, 9 men) performed supine plantar flexion exercise (30 contractions/min, increasing workload). A subset of subjects (n = 7 PAD, n = 8 healthy) also performed isometric handgrip exercise (40% of maximum voluntary contraction to fatigue). Coronary blood velocity in the left anterior descending artery was measured by transthoracic Doppler echocardiography; blood pressure and heart rate were monitored continuously. RESULTS: Coronary blood velocity responses to 4 min of plantar flexion exercise (PAD: Δ2.4 ± 1.2, healthy: Δ6.0 ± 1.6 cm/sec, P = 0.039) and isometric handgrip exercise (PAD: Δ8.3 ± 4.2, healthy: Δ16.9 ± 3.6, P = 0.033) were attenuated in PAD patients. CONCLUSION: These data indicate that coronary exercise hyperemia is impaired in PAD, which may predispose these patients to myocardial ischemia.

Revisional bariatric surgery: who, what, where, and when?

BACKGROUND: Revisional bariatric surgery (RBS) outcomes have been poorly characterized. We compared the RBS and primary bariatric surgery (PBS) outcomes at the Penn State Milton S. Hershey Medical Center in the United States. METHODS: A total of 72 RBS cases from 2000 to 2007 were reviewed and grouped by indication: failure of weight loss, gastrojejunal complications, or other. The RBS patients were compared with the 856 PBS patients who underwent Roux-en-Y gastric bypass. The mean follow-up time was 12.6 ± 1.2 months for the RBS group and 16 ± 0.5 months for the PBS group. Weight loss was analyzed as the kilograms lost and patients with ≥ 50% excess body weight loss (EBWL). Outcomes included mortality, leaks, surgical site infections, and length of stay. RESULTS: The weight loss was 23 ± 2.8 kg after RBS and 41.3 ± 0.7 kg after PBS (P <.05 versus PBS). The post-RBS weight loss varied by surgical indication: failure of weight loss, 27.1 ± 2 kg; gastrojejunal complications, 8.7 ± 3.4 kg; and other 23.5 ± 10.6 kg. Also, 29% of the RBS patients had ≥ 50% excess body weight loss (versus the prerevision weight) and 61% (versus the initial weight) compared with 52.7% after PBS. Only age ≤ 50 years was associated with ≥ 50% excess body weight loss after RBS for the failure of weight loss group. No RBS patients died. However, leaks, surgical site infections, and length of stay were increased after RBS. CONCLUSION: The results of our study have shown that weight loss after RBS varies with the surgical indication and is affected by age >50 years. Although the RBS patients had decreased weight loss and increased complications compared with the PBS patients, ≥ 50% EBWL was achieved by a significant number of RBS patients.

Nuclear factor-kappaB mediates the inhibitory effects of tumor necrosis factor-alpha on growth hormone-inducible gene expression in liver.

TNF inhibits serine protease inhibitor 2.1 (Spi 2.1) and IGF-I gene expression by GH in CWSV-1 hepatocytes. The current study describes construction of a GH-inducible IGF-I promoter construct and investigates mechanisms by which TNF and nuclear factor-kappaB (NFkappaB) inhibit GH-inducible gene expression. CWSV-1 cells were transfected with GH-inducible Spi 2.1 or IGF-I promoter luciferase constructs, incubated with TNF signaling inhibitors (fumonisin B1 for sphingomyelinase and SP600125 for c-Jun N-terminal kinase), treated with or without TNF, and then stimulated with recombinant human GH. The 5- to 6-fold induction of Spi 2.1 and IGF-I promoter activity by GH was inhibited by TNF. Neither fumonisin B1 nor SP600125 prevented the inhibitory effects of TNF on GH-inducible promoter activity. Dominant-negative inhibitor-kappaBalpha (IkappaBalpha) expression vectors (IkappaBalphaS/A or IkappaBalphaTrunc), p65 and p50 expression vectors, and p65 deletion constructs were used to investigate the NFkappaB pathway. IkappaBalphaS/A and IkappaBalphaTrunc ameliorated the inhibitory effects of TNF on GH-inducible Spi 2.1 and IGF-I promoter activity. Cotransfection of CWSV-1 cells with expression vectors for p65 alone or p50 and p65 together inhibited GH-inducible Spi 2.1 and IGF-I promoter activity. Cotransfection with a C-terminal p65 deletion (1-450) enhanced GH-inducible promoter activity, whereas the N-terminal deletion (31-551) was inhibitory for IGF-I but not Spi 2.1. Cycloheximide did not antagonize the inhibitory effects of TNF on GH-inducible IGF-I expression. We conclude the inhibitory effects of TNF on GH-inducible promoter activity are mediated by NFkappaB, especially p65, by a mechanism that does not require protein synthesis.