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Long-term outcomes in the smoking claudicant after peripheral vascular interventions

OBJECTIVE

Emphasis on tobacco cessation, given the urgent and emergent nature of vascular surgery, is less prevalent than standard elective cases such as hernia repairs, cosmetic surgery, and bariatric procedures. The goal of this study is to determine the effect of active smoking on claudicating individuals undergoing peripheral vascular interventions (PVIs). Our goal is to determine if a greater emphasis on education should be placed on smoking cessation in nonurgent cases scheduled through clinic visits and not the Emergency Department.

METHODS

This study was performed using the multi-institution de-identified Vascular Quality Initiative/Medicare-linked database (Vascular Implant Surveillance and Interventional Outcomes Network [VISION]). Claudicants who underwent PVI for peripheral arterial occlusive disease between 2004 and 2019 were included in our study. Our final sample consisted of a total of 18,726 patients: 3617 nonsmokers (19.3%) (NSs), 9975 former smokers (53.3%) (FSs), and 5134 current smokers (27.4%) (CSs). We performed propensity score matching on 29 variables (age, gender, race, ethnicity, treatment setting [outpatient or inpatient], obesity, insurance, hypertension, diabetes, coronary artery disease, congestive heart failure, chronic obstructive pulmonary disease, chronic kidney disease, previous coronary artery bypass graft, carotid endarterectomy, major amputation, inflow treatment, prior bypass or PVI, preoperative medications, level of treatment, concomitant endarterectomy, and treatment type [atherectomy, angioplasty, stent]) between NS vs FS and FS vs CS. Outcomes were long-term (5-year) overall survival (OS), limb salvage (LS), freedom from reintervention (FR), and amputation-free survival (AFS).

RESULTS

Propensity score matching resulted in 3160 well-matched pairs of NS and FS and 3750 well-matched pairs of FS and CS. There was no difference between FS and NS in terms of OS (hazard ratio [HR], 0.94; 95% confidence interval [CI], 0.82-1.09; P = .43), FR (HR, 0.96; 95% CI, 0.89-1.04; P = .35), or AFS (HR, 0.90; 95% CI, 0.79-1.03; P = .12). However, when compared with CS, we found FS to have a higher OS (HR, 1.18; 95% CI, 1.04-1.33; P = .01), less FR (HR, 0.89; 95% CI, 0.83-0.96; P = .003), and greater AFS (HR, 1.16; 95% CI, 1.03-1.31; P = .01).

CONCLUSIONS

This multi-institutional Medicare-linked study looking at elective PVI cases in patients with peripheral artery disease presenting with claudication found that FSs have similar 5-year outcomes in comparison to NSs in terms of OS, FR, and AFS. Additionally, CSs have lower OS and AFS when compared with FSs. Overall, this suggests that smoking claudicants should be highly encouraged and referred to structured smoking cessation programs or even required to stop smoking prior to elective PVI due to the perceived 5-year benefit.

Preoperative Risk Factors Impacting Length of Stay After Transcarotid Artery Revascularization

BACKGROUND

Transcarotid artery revascularization (TCAR), using interoperative flow reversal is a unique, hybrid operation utilized in treating critical carotid artery stenosis. Over the past decade, TCAR has been increasingly used to treat asymptomatic carotid artery disease and has a similar risk profile to traditional carotid endarterectomy. Postoperative length of stay (LOS) has a significant impact on cost-effectiveness and quality outcomes in this expanded setting. The objective of this study is to develop a multivariate regression model to identify key preoperative variables and their impact factor on LOS after TCAR for asymptomatic carotid artery stenosis. We hypothesized that high-risk preoperative patient factors historically identified in carotid endarterectomy would similarly impact LOS after TCAR.

METHODS

A multi-institution, retrospective study of all adult patients undergoing TCAR with flow-reversal for intraoperative neuroprotection was performed using the Society for Vascular Surgery Vascular Quality Initiative (VQI) from January 2016 to August 2021. Patients with prolonged preoperative hospitalization (preoperative LOS ≥1 day) were excluded to enhance the capture of carotid artery stenosis as the index admission. Univariate analysis was done on preoperative factors against LOS using nonparametric statistical tests. A multivariate model was then constructed using a negative binomial regression. The study population was split into 80% "training" data for model formulation and 20% "test" data for model validation.

RESULTS

Thirteen thousand four hundred eighty-three patients undergoing TCAR for asymptomatic carotid stenosis met the study's inclusion criteria with a median postoperative LOS of 1.82 days. Factors in VQI found to have a significant effect on LOS and retained in the multivariate model were lesion type (restenosis versus atherosclerotic), age, gender, chronic obstructive pulmonary disease, preoperative beta blocker, calcific lesion burden, hypertension status, and race (P < 0.05). The model accurately predicted LOS after TCAR within 1 day for 86.04% and within 2 days for 94.51% of patients in the test population.

CONCLUSIONS

This large-scale analysis from 2016 to 2021 spans a considerable expansion in the practice of TCAR for asymptomatic carotid disease. All preoperative variables shown to significantly increase the postoperative LOS were derived from the VQI data set. As LOS is a measure of health-care efficiency and cost-effectiveness, this model can be used to identify patients at risk for increased postoperative LOS. It has the potential to be incorporated into a patient/physician decision support tool to optimize resource planning and patient selection for elective TCAR.

Size thresholds for repair of abdominal aortic aneurysms warrant reconsideration

BACKGROUND

The historical size threshold for abdominal aortic aneurysm (AAA) repair is widely accepted to be 5.5 cm for men and 5.0 cm for women. However, contemporary AAA rupture risks may be lower than historical benchmarks, which has implications for when AAAs should be repaired. Our objective was to use contemporary AAA rupture rates to inform optimal size thresholds for AAA repair.

METHODS

We used a Markov chain analysis to estimate life expectancy for patients with AAA. The primary outcome was AAA-related mortality. We estimated survival using Social Security Administration life tables and published contemporary AAA rupture estimates. For those undergoing repair, we modified survival estimates using data from the Vascular Quality Initiative and Medicare on complications, late rupture, and open conversion. We used this model to estimate the AAA repair size threshold that minimizes AAA-related mortality for 60-year-old average-health men and women. We performed a sensitivity analysis of poor-health patients and 70- and 80-year-old base cases.

RESULTS

The annual risk of all-cause mortality under surveillance for a 60-year-old woman presenting with a 5.0 cm AAA using repair thresholds of 5.5 cm, 6.0 cm, 6.5 cm, and 7.0 cm was 1.7%, 2.3%, 2.7%, and 2.8%, respectively. The corresponding risk for a man was 2.3%, 2.9%, 3.3%, and 3.4% for the same repair thresholds, respectively. For a 60-year-old average-health woman, an AAA repair size of 6.1 cm was the optimal threshold to minimize AAA-related mortality. Life expectancy varied by <2 months for repair at sizes from 5.7 cm to 7.1 cm. For a 60-year-old average-health man, an AAA repair size of 6.9 cm was the optimal threshold to minimize AAA-related mortality. Life expectancy varied by <2 months for repair at sizes from 6.0 cm to 7.4 cm. Women in poor health, at various age strata, had optimal AAA repair size thresholds that were >6.5 cm, whereas men in poor health, at all ages, had optimal repair size thresholds that were >8.0 cm.

CONCLUSIONS

The optimal threshold for AAA repair is more nuanced than a discrete size. Specifically, there appears to be a range of AAA sizes for which repair is reasonable to minmized AAA-related mortality. Notably, they all are greater than current guideline recommendations. These findings would suggest that contemporary AAA size thresholds for repair should be reconsidered.

Long-term outcomes after lower extremity bypass in the actively smoking claudicant

OBJECTIVE

Smoking is known to increase complications, including poor wound healing, coagulation abnormalities, and cardiac and pulmonary ramifications. Across specialties, elective surgical procedures are commonly denied to active smokers. Given the base population of active smokers with vascular disease, smoking cessation is encouraged but is not required the way it is for elective general surgery procedures. We aim to study the outcomes of elective lower extremity bypass (LEB) in actively smoking claudicants.

METHODS

We queried the Vascular Quality Initiative Vascular Implant Surveillance and Interventional Outcomes Network LEB database from 2003 to 2019. In this database we found 609 (10.0%) never smokers (NS), 3388 (55.3%) former smokers (FS), and 2123 (34.7%) current smokers (CS) who underwent LEB for claudication. We performed two separate propensity score matches without replacement on 36 clinical variables (age, gender, race, ethnicity, obesity, insurance, hypertension, diabetes, coronary artery disease, congestive heart failure, chronic obstructive pulmonary disease, chronic kidney disease, previous coronary artery bypass graft, carotid endarterectomy, major amputation, inflow treatment, preoperative medications and treatment type), one of FS to NS and a second analysis of CS to FS. Primary outcomes included 5-year overall survival (OS), limb salvage (LS), freedom from reintervention (FR), and amputation-free survival (AFS).

RESULTS

Propensity score matches resulted in 497 well-matched pairs of NS and FS. In this analysis we found no difference in terms of OS (HR, 0.93; 95% CI, 0.70-1.24; P = .61), LS (HR, 1.07; 95% CI, 0.63-1.82; P = .80), FR (HR, 0.9; 95% CI,0.71-1.21; P = .59), or AFS (HR, 0.93; 95% CI,0.71-1.22; P = .62). In the second analysis, we had 1451 well-matched pairs of CS and FS. There was no difference in LS (HR, 1.36; 95% CI,0.94-1.97; P = .11) or FR (HR, 1.02; 95% CI,0.88-1.19; P = .76). However, we did find a significant increase in OS (HR, 1.37; 95% CI,1.15-1.64, P <.001) and AFS (HR, 1.38; 95% CI,1.18-1.62; P < .001) in FS compared with CS.

CONCLUSIONS

Claudicants represent a unique nonemergent vascular patient population that may require LEB. Our study found that FS have better OS and AFS when compared with CS. Additionally, FS mimic nonsmokers at 5-year outcomes for OS, LS, FR, and AFS. Therefore, structured smoking cessation should be a more prominent part of vascular office visits before elective LEB procedures in claudicants.

Capturing the Complexity of Open Abdominal Aortic Surgery in the Endovascular Era

OBJECTIVE

Volume and quality benchmarks for open abdominal aortic surgery and particularly open aortic aneurysm repair (OAR) in the endovascular era are guided by the Society for Vascular Surgery (SVS) guidelines, but the Vascular Quality Initiative (VQI) OAR module fails to capture the full spectrum of complex OAR. We hypothesized that VQI-ineligible complex OAR is the dominant form of open repairs performed at a VQI-participating tertiary center.

METHODS

All OAR cases performed at a single tertiary care center from 2007 to 2020 were reviewed. The VQI OAR criteria were applied with exclusions (non-VQI) defined as concomitant renal bypass, clamping above the superior mesenteric artery (SMA) or celiac artery, repairs performed for trauma, anastomotic aneurysm, isolated iliac aneurysm, or infected aneurysms. Linear regression was used to assess temporal trends.

RESULTS

Among a total of 481 open abdominal aortic operations, 355 (74%) were OAR. The average annual OAR volume remained stable over 14 years (25 ± 6; P = .46). Non-VQI OAR comprised 54% of all cases and persisted over time (R² = .047, P = .46). Supra-celiac clamping (35%) was often necessary. The proportion of endograft explantation cases significantly increased over time from 4% in 2007 to 20% in 2019 (P = .01). Infectious indications represented 20% (n = 70) of cases. Visceral branch grafts were performed in 16% of all cases. OAR for ruptured aneurysm constituted 10% of cases. Thirty-day mortality was significantly higher in non-VQI vs. VQI-eligible OAR cases (10% vs. 4%; P = .04).

CONCLUSIONS

Complex OAR comprises a majority of OAR cases in a contemporary tertiary referral hospital, yet these cases are not accounted for in the VQI. Creation of a "complex OAR" VQI module would capture these cases in a quality-driven national registry and help to better inform benchmarks for volume and outcomes in aortic surgery.

Outcomes of Axillofemoral Bypass for Intermittent Claudication

OBJECTIVE

While endovascular therapy is often first-line treatment for medically refractory intermittent claudication (IC) caused by aorto-femoral disease, suprainguinal bypass is commonly performed. Although this is often aorto-femoral bypass (AoFB), axillo-femoral bypass (AxFB) is still sometimes performed despite limited data evaluating its utility in the management of IC. Our goal was to assess the safety and durability of AxFB performed for IC.

METHODS

The Vascular Quality Initiative (2009-2019) was queried for suprainguinal bypass performed for IC. Univariable and multivariable analyses were used to compare perioperative and one-year outcomes between AxFB and a comparison cohort of AoFB.

RESULTS

We identified 3,261 suprainguinal bypasses performed for IC: 436 AxFB and 2,825 AoFB. Overall, mean age was 61.4 ± 9.1 years, 58.8% of patients were male sex, and 59.7% currently smoked. Patients undergoing AxFB, compared with AoFB, were more often older, male, never-smokers, and ambulated with assistance (all P<.001). They more often had hypertension, diabetes, coronary artery disease, congestive heart failure, chronic obstructive pulmonary disease, end-stage renal disease, previous outflow peripheral endovascular interventions, and previous inflow or outflow bypass. AxFB, compared with AoFB, were more often uni-femoral (all P<.05). Patients undergoing AxFB, compared with AoFB, had shorter postoperative length of stay (median 4 vs. 6 days) and fewer perioperative pulmonary (3% vs. 7.9%) and renal complications (5.5% vs. 9.9%), but more perioperative ipsilateral major amputations (.9% vs. 0.04%) (all P<.05). There were no significant differences in perioperative myocardial infarction (2.8% vs. 2.7%), stroke (.7% vs. 1.1%), and death (1.8% vs. 1.7%) rates, respectively. At one year, Kaplan-Meier analysis demonstrated that the AxFB, compared with AoFB cohort, exhibited higher rates of death (7.3% vs. 3.6%, P=.002); graft occlusion or death (14.3% vs. 7.2%, P=.001); ipsilateral major amputation or death (12.5% vs. 5.6%, P<.001); and reintervention, amputation, or death (19% vs. 8.6%, P<.001). On multivariable analysis, AxFB was independently associated with increased risk of one-year reintervention, amputation, or death (HR 1.6, 95% CI 1.03-2.4, P=.04).

CONCLUSIONS

This retrospective analysis suggests that long-term complications were more frequent in patients who underwent AxFB as compared to AoFB, although patients treated with AxFB were at higher risk with more comorbidities. Since AxFB is associated with significant perioperative morbidity, mortality, and long-term complications, serious consideration should be given prior to its use for IC.

Prior Infrarenal Aortic Surgery is Not Associated with Increased Risk of Spinal Cord Ischemia Following Thoracic Endovascular Aortic Repair and Complex Endovascular Aortic Repair

OBJECTIVES

Patients with prior infrarenal aortic intervention represent an increasing demographic of patients undergoing thoracic endovascular aortic repair (TEVAR) and/or complex EVAR. Studies have suggested that prior abdominal aortic surgery is a risk factor for spinal cord ischemia (SCI). However, these results are largely based on single-center experiences with limited multi-institutional and national data assessing clinical outcomes in these patients. The objective of this study was to evaluate the effect of prior infrarenal aortic surgery on SCI.

METHODS

The Society for Vascular Surgery Vascular Quality Initiative database was retrospectively reviewed to identify all patients ≥18 years old undergoing TEVAR/complex EVAR from January 2012 to June 2020. Patients with previous thoracic or suprarenal aortic repairs were excluded. Baseline and procedural characteristics and postoperative outcomes were compared by group: TEVAR/complex EVAR with or without previous infrarenal aortic repair. The primary outcome was postoperative SCI. Secondary outcomes included postoperative hospital length of stay (LOS), bowel ischemia, renal ischemia, and 30-day mortality. Multivariate regression was used to determine independent predictors of postoperative SCI. Additional analysis was performed for patients undergoing isolated TEVAR.

RESULTS

A total of 9506 patients met the inclusion criteria: 8691 (91.4%) had no history of infrarenal aortic repair and 815 (8.6%) had previous infrarenal aortic repair. Patients with previous infrarenal repair were older with an increased prevalence of chronic kidney disease (p=0.001) and cardiovascular risk factors including hypertension, chronic obstructive pulmonary disease, and smoking history (p<0.001). These patients presented with larger maximal aortic diameters (6.06±1.47 cm versus 5.15±1.76 cm; p<0.001) and required more stent grafts (p<0.001) with increased intraoperative blood transfusion requirements (p<0.001), and longer procedure times (p<0.001). Univariate analysis demonstrated no difference in postoperative SCI, postoperative hospital LOS, bowel ischemia, or renal ischemia between the two groups. Thirty-day mortality was significantly higher in patients with prior infrarenal repair (p=0.001). On multivariate regression, prior infrarenal aortic repair was not a predictor of postoperative SCI, while aortic dissection (odds ratio [OR] 1.65; 95% confidence interval [CI] 1.26-2.16, p<0.001), number of stent grafts deployed (OR 1.45; 95% CI 1.30-1.62, p<0.001), and units of packed red blood cells transfused intraoperatively (OR 1.33; 95% CI 1.03-1.73, p=0.032) were independent predictors of SCI.

CONCLUSIONS

Although TEVAR/complex EVAR patients with prior infrarenal aortic repair constituted a sicker cohort with higher 30-day mortality, the rate of SCI was comparable to patients without prior repair. Previous infrarenal repair was not associated with risk of SCI.

Black patients have a higher burden of comorbidities but a lower risk of 30-day and 1-year mortality after thoracic endovascular aortic repair

BACKGROUND

Racial disparities in open thoracic aortic aneurysm repair have been well-documented, with Black patients reported to suffer from poor outcomes compared with their White counterparts. It is unclear whether these disparities extend to the less invasive thoracic endovascular aortic repair (TEVAR). This study aims to examine the clinical characteristics, perioperative outcomes, and 1-year survival of Black vs White patients undergoing TEVAR in a national vascular surgery database.

METHODS

The Vascular Quality Initiative database was retrospectively queried to identify all patients who underwent TEVAR between January 2011 and December 2019. The primary outcomes were 30-day mortality and 1-year survival after TEVAR. Secondary outcomes included various types of major postoperative complications. Multivariable logistic regression analyses were performed to identify predictors of 30-day mortality and perioperative complications. Multivariable Cox regression analysis was used to determine the predictors of 1-year survival.

RESULTS

A total of 2669 patients with TEVAR were identified in the Vascular Quality Initiative, of whom 648 were Black patients (24.3%). Compared with White patients, Black patients were younger and had a higher burden of comorbidities, including hypertension, diabetes, congestive heart failure, dialysis dependence, and anemia. Black patients were more likely to be symptomatic, present with aortic dissection, and undergo urgent or emergent repair. There was no statistically significant difference in 30-day mortality between Black and White patients (3.4% vs 4.9%; P = .1). After adjustment for demographics, comorbidities, and operative factors, Black patients were independently associated with a 56% decrease in 30-day mortality risk compared with their White counterparts (odds ratio, 0.44; 95% confidence interval [CI], 0.22-0.85; P = .01) and not associated with an increased risk of perioperative complications (odds ratio, 0.90; 95% CI, 0.68-1.17; P = .42). Black patients also had a significantly better 1-year overall survival (log-rank, P = .024) and were associated with a significantly decreased 1-year mortality (hazard ratio, 0.65; 95% CI, 0.47-0.91; P = .01) after adjusting for multiple clinical factors.

CONCLUSIONS

Although Black patients carried a higher burden of comorbidities, the racial disparities in perioperative outcomes and 1-year survival do not persist in TEVAR.

Use of data from the Vascular Quality Initiative registry to support regulatory decisions yielded a high return on investment

BACKGROUND

Real-world data (RWD) from the Society for Vascular Surgery Vascular Quality Initiative (VQI) registry has been used to support US Food and Drug Administration (FDA) regulatory decisions regarding vascular devices. The variables of cost and time needed for these registry-based studies have not been previously compared to traditional, independent, industry studies that would otherwise have been conducted to support regulatory decisions.

OBJECTIVES

To determine the potential value (cost and time saving and return on investment) created by device evaluation studies using the VQI registry infrastructure.

METHODS

We compared studies that used data from the VQI registry with estimated costs of independent industry studies (counterfactual studies) using an established model using design specifications determined by FDA reviewers.

RESULTS

We analyzed the initial six studies evaluating vascular devices for regulatory decisions using data from the VQI registry that generated evidence for four device manufacturers. Return on investment for these studies was estimated to be 143% and cost saving as 59% based on an actual per patient (with 5-year follow-up) cost of US$11K using VQI data versus US$26K from the counterfactual when averaged across all studies. Significant enrollment time savings (45%-71%) were also realized compared with industry-based estimates.

CONCLUSIONS

The use of RWD from the VQI registry in this study and the transcatheter valve treatment coordinated registry network in a prior study indicates that substantial value was added to device evaluation projects by the reuse of registry data, with additional potential savings if linked claims data can be used instead of costly long-term in-person follow-up.