Association of stroke or death with severity of carotid lesion calcification in patients undergoing carotid artery stenting

OBJECTIVE

Carotid artery stenting (CAS) for heavily calcified lesions is controversial due to concern for stent failure and increased perioperative stroke risk. However, the degree to which calcification affects outcomes is poorly understood, particularly in transcarotid artery revascularization (TCAR). With the precipitous increase in TCAR use and its expansion to standard surgical-risk patients, we aimed to determine the impact of lesion calcification on CAS outcomes to ensure its safe and appropriate use.

METHODS

We identified patients in the Vascular Quality Initiative who underwent first-time transfemoral CAS (tfCAS) and TCAR between 2016 and 2021. Patients were stratified into groups based on degree of lesion calcification: no calcification, 1% to 50% calcification, 51% to 99% calcification, and 100% circumferential calcification or intraluminal protrusion. Outcomes included in-hospital and 1-year composite stroke/death, as well as individual stroke, death, and myocardial infarction outcomes. Logistic regression was used to evaluate associations between degree of calcification and these outcomes.

RESULTS

Among 21,860 patients undergoing CAS, 28% patients had no calcification, 34% had 1% to 50% calcification, 35% had 51% to 99% calcification, and 3% had 100% circumferential calcification/protrusion. Patients with 51% to 99% and circumferential calcification/protrusion had higher odds of in-hospital stroke/death (odds ratio [OR], 1.3; 95% confidence interval [CI], 1.02-1.6; P = .034; OR, 1.9; 95% CI, 1.1-2.9; P = .004, respectively) compared with those with no calcification. Circumferential calcification was also associated with increased risk for in-hospital myocardial infarction (OR, 3.5; 95% CI, 1.5-8.0; P = .003). In tfCAS patients, only circumferential calcification/protrusion was associated with higher in-hospital stroke/death odds (OR, 2.0; 95% CI, 1.2-3.4; P = .013), whereas for TCAR patients, 51% to 99% calcification was associated with increased odds of in-hospital stroke/death (OR, 1.5; 95% CI, 1.1-2.2; P = .025). At 1 year, circumferential calcification/protrusion was associated with higher odds of ipsilateral stroke/death (12.4% vs 6.6%; hazard ratio, 1.64; P = .002).

CONCLUSIONS

Among patients undergoing CAS, there is an increased risk of in-hospital stroke/death for lesions with >50% calcification or circumferential/protruding plaques. Increasing severity of carotid lesion calcification is a significant risk factor for stroke/death in patients undergoing CAS, regardless of approach.

Risk of Stroke, Death, and Myocardial Infarction Following Transcarotid Artery Revascularization vs Carotid Endarterectomy in Patients With Standard Surgical Risk

Importance

Carotid artery stenting has been limited to use in patients with high surgical risk; outcomes in patients with standard surgical risk are not well known.

Objective

To compare stroke, death, and myocardial infarction outcomes following transcarotid artery revascularization vs carotid endarterectomy in patients with standard surgical risk.

Design, Setting, and Participants

This retrospective propensity-matched cohort study was conducted from August 2016 to August 2019 with follow-up until August 31, 2020, using data from the multicenter Vascular Quality Initiative Carotid Artery Stent and Carotid Endarterectomy registries. Patients with standard surgical risk, defined as those lacking Medicare-defined high medical or surgical risk characteristics and undergoing transcarotid artery revascularization (n = 2962) or carotid endarterectomy (n = 35 063) for atherosclerotic carotid disease. In total, 760 patients were excluded for treatment of multiple lesions or in conjunction with other procedures.

Exposures

Transcarotid artery revascularization vs carotid endarterectomy.

Main Outcomes and Measures

The primary outcome was a composite end point of 30-day stroke, death, or myocardial infarction or 1-year ipsilateral stroke.

Results

After 1:3 matching, 2962 patients undergoing transcarotid artery revascularization (mean [SD] age, 70.4 [6.9] years; 1910 [64.5%] male) and 8886 undergoing endarterectomy (mean [SD] age, 70.0 [6.5] years; 5777 [65.0%] male) were identified. There was no statistically significant difference in the risk of the primary composite end point between the 2 cohorts (transcarotid 3.0% vs endarterectomy 2.6%; absolute difference, 0.40% [95% CI, -0.43% to 1.24%]; relative risk [RR], 1.14 [95% CI, 0.87 to 1.50]; P = .34). Transcarotid artery revascularization was associated with a higher risk of 1-year ipsilateral stroke (1.6% vs 1.1%; absolute difference, 0.52% [95% CI, 0.03 to 1.08]; RR, 1.49 [95% CI, 1.05 to 2.11%]; P = .02) but no difference in 1-year all-cause mortality (2.6% vs 2.5%; absolute difference, -0.13% [95% CI, -0.18% to 0.33%]; RR, 1.04 [95% CI, 0.78 to 1.39]; P = .67).

Conclusions and Relevance

In this study, the risk of 30-day stroke, death, or myocardial infarction or 1-year ipsilateral stroke was similar in patients undergoing transcarotid artery revascularization compared with those undergoing endarterectomy for carotid stenosis.

Outcomes after transcarotid artery revascularization stratified by preprocedural symptom status

OBJECTIVE

Previous studies on carotid endarterectomy and transfemoral carotid artery stenting demonstrated that perioperative outcomes differed according to preoperative neurologic injury severity, but this has not been assessed in transcarotid artery revascularization (TCAR). In this study, we examined contemporary perioperative outcomes in patients who underwent TCAR stratified by specific preprocedural symptom status.

METHODS

Patients who underwent TCAR between 2016 and 2021 in the Vascular Quality Initiative were included. We stratified patients into the following groups based on preprocedural symptoms: asymptomatic, recent (symptoms occurring <180 days before TCAR) ocular transient ischemic attack (TIA), recent hemispheric TIA, recent stroke, or formerly symptomatic (symptoms occurring >180 days before TCAR). First, we used trend tests to assess outcomes in asymptomatic patients versus those with an increasing severity of recent neurologic injury (recent ocular TIA vs recent hemispheric TIA vs recent stroke). Then, we compared outcomes between asymptomatic and formerly symptomatic patients. Our primary outcome was in-hospital stroke/death rates. Multivariable logistic regression was used to adjust for demographics and comorbidities across groups.

RESULTS

We identified 18,477 patients undergoing TCAR, of whom 62.0% were asymptomatic, 3.2% had a recent ocular TIA, 7.6a % had recent hemispheric TIA, 18.0% had a recent stroke, and 9.2% were formerly symptomatic. In patients with recent symptoms, we observed higher rates of stroke/death with increasing neurologic injury severity: asymptomatic 1.1% versus recent ocular TIA 0.8% versus recent hemispheric TIA 2.1% versus recent stroke 3.1% (Ptrend < .01). In formerly symptomatic patients, the rate of stroke/death was higher compared with asymptomatic patients, but this difference was not statistically significant (1.7% vs 1.1%; P = .06). After risk adjustment, compared with asymptomatic patients, there was a higher odds of stroke/death in patients with a recent stroke (odds ratio [OR], 2.8; 95% confidence interval [CI], 2.1-3.7; P < .01), a recent hemispheric TIA (OR, 2.0; 95% CI, 1.3-3.0; P < .01), and former symptoms (OR, 1.6; 95% CI, 1.1-2.5; P = .02), but there was no difference in stroke/death rates in patients with a recent ocular TIA (OR, 0.9; 95% CI, 0.4-2.2; P = .78).

CONCLUSIONS

After TCAR, compared with asymptomatic status, a recent stroke and a recent hemispheric TIA were associated with higher stroke/death rates, whereas a recent ocular TIA was associated with similar stroke/death rates. In addition, a formerly symptomatic status was associated with higher stroke/death rates compared with an asymptomatic status. Overall, our findings suggest that classifying patients undergoing TCAR as symptomatic versus asymptomatic may be an oversimplification and that patients' specific preoperative neurologic symptoms should instead be used in risk assessment and outcome reporting for TCAR.

Association of Adoption of Transcarotid Artery Revascularization With Center-Level Perioperative Outcomes

IMPORTANCE

Transcarotid artery revascularization (TCAR) may serve as a safer alternative to carotid endarterectomy (CEA) for certain patients with carotid artery stenosis.

OBJECTIVE

To determine the center-level association of TCAR adoption with overall perioperative outcomes for TCAR and CEA combined at centers performing both procedures.

DESIGN, SETTING, AND PARTICIPANTS

This comparative-effectiveness research was conducted with a difference-in-difference analysis using retrospective data from 2015 to 2019 from the Vascular Quality Initiative registry, a consortium of more than 400 centers in North America. Included patients underwent TCAR or CEA for carotid artery stenosis. Patients who underwent transfemoral carotid stenting were excluded. Data were analyzed from December 2019 through August 2020.

EXPOSURES

Center-level adoption of TCAR vs not.

MAIN OUTCOMES AND MEASURES

The rate of major adverse cardiovascular events (MACE), a composite of in-hospital stroke, myocardial infarction, or death at 30 days, was measured.

RESULTS

Among 86 027 patients who underwent revascularization for carotid artery stenosis, 7664 patients (8.9%) underwent TCAR (mean [SD] age, 73.1 [9.6] years; 2788 [36.4%] women; 6938 White patients [90.6%]; and 3741 patients with symptoms [48.8%]) and 78 363 patients (91.1%) underwent CEA (mean [SD] age, 70.6 [9.2] years; 30 928 [39.5%] women; 70 663 White patients [90.2%]; and 37 883 patients with symptoms [48.3%]). The number of centers performing both TCAR and CEA increased from 15 centers in 2015 to 247 centers in 2019, a more than 16-fold increase. The proportion of all carotid procedures that were TCARs increased from 90 of 12 276 (0.7%) in 2015 to 2718 of 15 956 (17.0%) in 2019, a 24-fold increase. Overall, the crude rate of MACE was similar for TCAR and CEA (178 patients [2.3%] after TCAR vs 1842 patients [2.4%] after CEA; P = .91). However, the rate of MACE over time decreased for CEA (406 of 16 404 patients [2.5%] in 2015 vs 189 of 10 097 patients [1.9%] in 2019; P for trend < .001). The rate of MACE over time decreased for TCAR as well, but the change was not statistically significant (4 of 128 patients [3.1%] in 2016 vs 59 of 2718 patients [2.2%] in 2019; P for trend = .07). Difference-in-difference analysis demonstrated that centers that adopted TCAR had a 10% decrease in the likelihood of MACE at 12 months after TCAR adoption vs if those centers had continued to perform CEA alone (odds ratio, 0.90; 95% CI, 0.81-0.99; P = .04).

CONCLUSIONS AND RELEVANCE

This comparative-effectiveness study of a cohort of patients who underwent TCAR or CEA found that availability of TCAR at a hospital was associated with a decrease in the likelihood of perioperative MACE after carotid revascularization.

Vascular Quality Initiative risk score for 30-day stroke or death following transcarotid artery revascularization

OBJECTIVE

Transcarotid artery revascularization (TCAR) using a flow-reversal neuroprotection system has gained popularity for the endovascular treatment of carotid artery atherosclerotic disease owing to its lower risk of stroke or death compared with transfemoral carotid artery stenting. However, specific risk factors associated with stroke or death complications after TCAR have yet to be defined.

METHODS

All patients undergoing TCAR for the treatment of asymptomatic or symptomatic atherosclerotic carotid disease were identified between September 2016 and September 2019 in the Vascular Quality Initiative TCAR Surveillance Project. Our primary outcome was 30-day stroke or death. We created a risk model for 30-day stroke or death using multivariable fractional polynomials and internally validated the model using bootstrapping.

RESULTS

During the study period 7633 patients underwent TCAR, of which 4089 (53.6%) were treated for symptomatic and 3544 (46.4%) for asymptomatic disease. The average age of patients undergoing TCAR was 73.3 ± 9.1 years and 63.7% were male. Stroke or death events within 30 days of the index operation occurred in 153 patients (2.0%). Factors independently associated with a higher odds of 30-day stroke or death included the severity of presenting stroke symptoms (cortical transient ischemic attack, odds ratio [OR], 2.17 [95% confidence interval (CI), 1.21-3.90; P = .009]; stroke, OR, 3.30; 95% CI, 2.25-4.85; P < .001), advancing age (OR, 1.03 per year; 95% CI, 1.01-1.06; P = .003), and history of unstable angina or myocardial infarction within the past 6 months (OR, 2.20; 95% CI, 1.29-3.77; P = .004), moderate or severe congestive heart failure (OR, 2.44; 95% CI, 1.31-4.55; P = .005), chronic obstructive pulmonary disease (on medications, OR, 1.61 [95% CI, 1.06-2.43; P = .024]; on home oxygen, OR, 2.52 [95% CI, 1.44-4.41; P = .001]), and prior ipsilateral carotid endarterectomy (OR, 1.56; 95% CI, 1.09-2.25; P = .016), whereas preoperative P2Y₁₂ use was associated with a lower odds of 30-day stroke or death (OR, 0.57; 95% CI, 0.39-0.85; P = .005). A 30-point risk prediction model created based on these criteria produced a C statistic of 0.72 and Hosmer-Lemeshow goodness of fit of 0.97. Internal validation demonstrated good discrimination with a bias corrected area under the receiver operating characteristic curve of 0.70 with a calibration slope of 1.00.

CONCLUSIONS

This Vascular Quality Initiative TCAR risk score calculator can be used to estimate the risk of stroke or death within 30 days of the procedure. Because TCAR is commonly used to treat patients with high surgical risk for carotid endarterectomy, this risk score will help to guide treatment decisions in patients being considered for TCAR.

Risk factors and impact of postoperative hypotension after carotid artery stenting in the Vascular Quality Initiative

OBJECTIVE

Hypotension is a frequent complication of carotid artery stenting (CAS). Although common, its occurrence is unpredictable, and association with adverse events has not been well defined. The aim of this study was to identify predictors of postoperative hypotension after CAS and the association with stroke/transient ischemic attack (TIA), major adverse cardiac events (MACEs), increased length of stay (LOS), and in-hospital mortality.

METHODS

This is a retrospective analysis of all CAS procedures, including transfemoral CAS (TF-CAS) and transcarotid artery revascularization (TCAR), performed in the Vascular Quality Initiative between 2003 and 2018. The primary study end point was postoperative hypotension, defined as hypotension treated with continuous infusion of a vasoactive agent for ≥15 minutes. Secondary end points included any postoperative neurologic events (stroke/TIA), MACEs (myocardial infarction, congestive heart failure, and dysrhythmias), prolonged LOS (>1 day), and in-hospital mortality. Patients' demographics predictive of hypotension were determined by multivariable logistic regression, and a risk score was developed for correlation with outcomes.

RESULTS

During the time period of study, 24,699 patients underwent CAS; 19,716 (80%) were TF-CAS, 3879 (16%) were TCAR, and 1104 (4%) were not defined. Fifty-six percent were for symptomatic disease, 75% were for a primary atherosclerotic lesion, and 72% were performed under local or regional anesthesia. Postoperative hypotension occurred in 15% of TF-CAS and 14% of TCAR patients (P = .50). Patients with hypotension (vs no hypotension) had higher rates of stroke/TIA (7.3% vs 2.6%; P < .001), MACEs (9.6% vs 2.1%; P < .001), prolonged LOS (65% vs 28%; P < .001), and in-hospital mortality (2.9% vs 0.7%; P < .001). By multivariable analysis, risk factors associated with hypotension included an atherosclerotic (vs restenotic) lesion (odds ratio, 2.2; 95% confidence interval, 2.0-2.4; P < .001), female sex (1.3 [1.2-1.4]; P < .001), positive stress test result (1.3 [1.2-1.4]; P < .001), age 70 to 79 years (1.1 [1.1-1.3]; P < .002), age >80 years (1.2 [1.1-1.4]; P < .001), history of myocardial infarction or angina (1.3 [1.2-1.4]; P < .001), and an urgent (vs elective) procedure (1.1 [1.0-1.2]; P < .01). A history of hypertension was protective (0.9 [0.8-0.9]; P < .02). A normalized risk score for hypotension was created from the multivariable model. Increasing risk scores correlated directly with rates of adverse events, including postoperative stroke/TIA, MACEs, increased LOS, and increased in-hospital mortality.

CONCLUSIONS

Hypotension after CAS is associated with adverse neurologic and cardiac events as well as with prolonged LOS and in-hospital mortality. A scoring tool may be valuable in stratifying patients at risk. Interventions aimed at preventing postoperative hypotension may improve outcomes with CAS.

Clinical impact of sex on carotid revascularization

BACKGROUND

The impact of sex in the management of carotid disease is unclear in the current literature. Therefore, we evaluated the effect of sex on perioperative outcomes following carotid endarterectomy (CEA) and carotid artery stenting (CAS).

METHODS

We included patients who underwent CEA or CAS between 2012 and 2017 in the Vascular Quality Initiative database. Our primary outcome was perioperative stroke/death. Secondary outcomes were in-hospital stroke, 30-day mortality, and in-hospital MI. We compared perioperative outcomes between female and male patients, stratified by treatment modality and symptom status, and used multivariable regression to account for differences in baseline characteristics.

RESULTS

A total of 83,436 patients underwent either a CEA (71,383) or CAS (12,053). Asymptomatic and symptomatic CEA females were less likely to be on a preoperative antiplatelet agent, when compared to males. Females overall, were less likely to be on a preoperative statin and more likely to have chronic obstructive pulmonary disease. Within the CAS cohort, females were more likely to have a previous ipsilateral CEA. There were no differences between males and females in major adverse events following CEA for asymptomatic disease. Following CEA for symptomatic disease, there was no difference in stroke/death rate or in-hospital stroke. However, females experienced a higher 30-mortality after adjustment (univariate: 1.0% vs 0.7%, P = .04; adjusted: odds ratio [OR], 1.4:1.02-1.94). Following CAS for asymptomatic disease, females experienced a higher rate of perioperative stroke/death (2.9% vs 1.9% P = .02; OR, 1.5: 1.05-2.03) and in-hospital stroke (2.1% vs 1.2% P = .01; OR, 1.8: 1.20-2.60). There were no differences in outcomes for symptomatic females vs males undergoing CAS.

CONCLUSIONS

Females with carotid disease less frequently receive optimal medical treatment with antiplatelet agents and statins. This is an important target area for quality improvement issue in both females and males. Furthermore, among symptomatic CEA patients the female sex is associated with higher mortality and among asymptomatic CAS patients, females experience higher rates of stroke/death. These findings suggest that careful patient selection is necessary in the treatment of female patients. Quality improvement projects should be created to further investigate and eliminate the disparities of optimal medical management between the sexes.

Association of Transcarotid Artery Revascularization vs Transfemoral Carotid Artery Stenting With Stroke or Death Among Patients With Carotid Artery Stenosis

Importance

Several trials have observed higher rates of perioperative stroke following transfemoral carotid artery stenting compared with carotid endarterectomy. Transcarotid artery revascularization with flow reversal was recently introduced for carotid stenting. This technique was developed to decrease stroke risk seen with the transfemoral approach; however, its outcomes, compared with transfemoral carotid artery stenting, are not well characterized.

Objective

To compare outcomes associated with transcarotid artery revascularization and transfemoral carotid artery stenting.

Design, Setting, and Participants

Exploratory propensity score-matched analysis of prospectively collected data from the Vascular Quality Initiative Transcarotid Artery Surveillance Project and Carotid Stent Registry of asymptomatic and symptomatic patients in the United States and Canada undergoing transcarotid artery revascularization and transfemoral carotid artery stenting for carotid artery stenosis, from September 2016 to April 2019. The final date for follow-up was May 29, 2019.

Exposures

Transcarotid artery revascularization vs transfemoral carotid artery stenting.

Main Outcomes and Measures

Outcomes included a composite end point of in-hospital stroke or death, stroke, death, myocardial infarction, as well as ipsilateral stroke or death at 1 year. In-hospital stroke was defined as ipsilateral or contralateral, cortical or vertebrobasilar, and ischemic or hemorrhagic stroke. Death was all-cause mortality.

Results

During the study period, 5251 patients underwent transcarotid artery revascularization and 6640 patients underwent transfemoral carotid artery stenting. After matching, 3286 pairs of patients who underwent transcarotid artery revascularization or transfemoral carotid artery stenting were identified (transcarotid approach: mean [SD] age, 71.7 [9.8] years; 35.7% women; transfemoral approach: mean [SD] age, 71.6 [9.3] years; 35.1% women). Transcarotid artery revascularization was associated with a lower risk of in-hospital stroke or death (1.6% vs 3.1%; absolute difference, -1.52% [95% CI, -2.29% to -0.75%]; relative risk [RR], 0.51 [95% CI, 0.37 to 0.72]; P < .001), stroke (1.3% vs 2.4%; absolute difference, -1.10% [95% CI, -1.79% to -0.41%]; RR, 0.54 [95% CI, 0.38 to 0.79]; P = .001), and death (0.4% vs 1.0%; absolute difference, -0.55% [95% CI, -0.98% to -0.11%]; RR, 0.44 [95% CI, 0.23 to 0.82]; P = .008). There was no statistically significant difference in the risk of perioperative myocardial infarction between the 2 cohorts (0.2% for transcarotid vs 0.3% for the transfemoral approach; absolute difference, -0.09% [95% CI, -0.37% to 0.19%]; RR, 0.70 [95% CI, 0.27 to 1.84]; P = .47). At 1 year using Kaplan-Meier life-table estimation, the transcarotid approach was associated with a lower risk of ipsilateral stroke or death (5.1% vs 9.6%; hazard ratio, 0.52 [95% CI, 0.41 to 0.66]; P < .001). Transcarotid artery revascularization was associated with higher risk of access site complication resulting in interventional treatment (1.3% vs 0.8%; absolute difference, 0.52% [95% CI, -0.01% to 1.04%]; RR, 1.63 [95% CI, 1.02 to 2.61]; P = .04), whereas transfemoral carotid artery stenting was associated with more radiation (median fluoroscopy time, 5 minutes [interquartile range {IQR}, 3 to 7] vs 16 minutes [IQR, 11 to 23]; P < .001) and more contrast (median contrast used, 30 mL [IQR, 20 to 45] vs 80 mL [IQR, 55 to 122]; P < .001).

Conclusions and Relevance

Among patients undergoing treatment for carotid stenosis, transcarotid artery revascularization, compared with transfemoral carotid artery stenting, was significantly associated with a lower risk of stroke or death.

In-hospital outcomes of transcarotid artery revascularization and carotid endarterectomy in the Society for Vascular Surgery Vascular Quality Initiative

OBJECTIVE

Transcarotid artery revascularization (TCAR) with flow reversal offers a less invasive option for carotid revascularization in high-risk patients and has the lowest reported overall stroke rate for any prospective trial of carotid artery stenting. However, outcome comparisons between TCAR and carotid endarterectomy (CEA) are needed to confirm the safety of TCAR outside of highly selected patients and providers.

METHODS

We compared in-hospital outcomes of patients undergoing TCAR and CEA from January 2016 to March 2018 using the Society for Vascular Surgery Vascular Quality Initiative TCAR Surveillance Project registry and the Society for Vascular Surgery Vascular Quality Initiative CEA database, respectively. The primary outcome was a composite of in-hospital stroke and death.

RESULTS

A total of 1182 patients underwent TCAR compared with 10,797 patients who underwent CEA. Patients undergoing TCAR were older (median age, 74 vs 71 years; P < .001) and more likely to be symptomatic (32% vs 27%; P < .001); they also had more medical comorbidities, including coronary artery disease (55% vs 28%; P < .001), chronic heart failure (20% vs 11%; P < .001), chronic obstructive pulmonary disease (29% vs 23%; P < .001), and chronic kidney disease (39% vs 34%; P = .001). On unadjusted analysis, TCAR had similar rates of in-hospital stroke/death (1.6% vs 1.4%; P = .33) and stroke/death/myocardial infarction (MI; 2.5% vs 1.9%; P = .16) compared with CEA. There was no difference in rates of stroke (1.4% vs 1.2%; P = .68), in-hospital death (0.3% vs 0.3%; P = .88), 30-day death (0.9% vs 0.4%; P = .06), or MI (1.1% vs 0.6%; P = .11). However, on average, TCAR procedures were 33 minutes shorter than CEA (78 ± 33 minutes vs 111 ± 43 minutes; P < .001). Patients undergoing TCAR were also less likely to incur cranial nerve injuries (0.6% vs 1.8%; P < .001) and less likely to have a postoperative length of stay >1 day (27% vs 30%; P = .046). On adjusted analysis, there was no difference in terms of stroke/death (odds ratio, 1.3; 95% confidence interval, 0.8-2.2; P = .28), stroke/death/MI (odds ratio, 1.4; 95% confidence interval, 0.9-2.1, P = .18), or the individual outcomes.

CONCLUSIONS

Despite a substantially higher medical risk in patients undergoing TCAR, in-hospital stroke/death rates were similar between TCAR and CEA. Further comparative studies with larger samples sizes and longer follow-up will be needed to establish the role of TCAR in extracranial carotid disease management.

Variation in timing and type of groin wound complications highlights the need for uniform reporting standards

BACKGROUND

Groin wound infections represent a substantial source of patients' morbidity and resource utilization. Definitions and reporting times of groin infections are poorly standardized, which limits our understanding of the true scope of the problem and potentially leads to event under-reporting. Our objective was to investigate the timing and variation of groin wound complications after vascular surgery.

METHODS

We reviewed all patients who underwent vascular surgery with a groin incision at our institution during 2013 (N = 256; 32% female; mean age, 68.8 years). We analyzed patient- and procedure-level variables. Our primary outcome was any groin complication within 180 days. We classified groin-related events as major (hospital readmission or reoperation for groin wound) or minor (wound opened in clinic, initiation of antibiotics specifically for a groin wound, or new groin hematoma or wound drainage).

RESULTS

The Kaplan-Meier estimated rate of groin complications at 180 days was 23% (n = 53/256); 29 (54%) were major and 24 (46%) were minor. The Kaplan-Meier 30-day event rate was 13% for any complication and only 3% for major complications, indicating that most events occurring within the first 30 days did not require readmission or reoperation. By 180 days, the overall complication rate rose to 23% and the major event rate to 14%, indicating that nearly all complications occurring after 30 days required readmission or reoperation. Those with a groin complication more commonly had tissue loss (23% vs 12%; P = .05), underwent infrainguinal bypass (42% vs 22%; P=.004), had a redo incision (32% vs 18%; P = .03), and had a longer operation (77% vs 65% surgery >200 minutes; P = .07). There were no significant differences in patients' comorbidities, skin closure, dressing type, prosthetic implants, hemostatic agents, or discharge status.

CONCLUSIONS

Whereas >20% of patients suffered a groin complication, nearly half of these events occurred after 30 days. Standardized reporting measures limited to 30-day events or infection definitions that are limited to the need for antibiotic use may misrepresent the true infection rate and thus highlight the need for uniform reporting standards.

Regional variation in patient outcomes in carotid artery disease treatment in the Vascular Quality Initiative

OBJECTIVE

Quality metrics were developed to improve outcomes after carotid artery revascularization; however, few studies have evaluated regional differences in perioperative outcomes. This study aimed to evaluate regional variation in mortality and perioperative outcomes after carotid endarterectomy (CEA) and carotid artery stenting (CAS).

METHODS

We identified all patients who underwent CEA or CAS from 2009 to 2016 in the Vascular Quality Initiative. Patients were analyzed on the basis of their symptom status. We assessed variation in perioperative outcomes using χ² analysis, Fisher exact test, and t-test, where appropriate.

RESULTS

A total of 78,467 carotid interventions were identified; 85% were CEAs, with 69% of those asymptomatic. Within CAS, 39% were asymptomatic. Perioperative stroke/death varied across regions within both CAS groups (asymptomatic, 0%-5.8% [P = .03]; symptomatic, 2.4%-8.1% [P = .1]), and several regions did not meet the American Heart Association (AHA) guidelines of 3% for asymptomatic patients and 6% for symptomatic patients, which persisted after risk adjustment. For CEA, the stroke/death rates fell within the standards set by the AHA guidelines in all regions for both the unadjusted and risk-adjusted models; however, there was significant regional variation in the cohorts (asymptomatic, 0.9%-3.1% [P < .01]; symptomatic, 1.3%-4.9% [P < .01]). Variation in 30-day mortality was significant in symptomatic patients (asymptomatic: CEA, 0%-1.3% [P = .2], CAS, 0%-2.4% [P = .2]; symptomatic: CEA, 0%-1.8% [P < .01], CAS, 0%-4.6% [P = .01]). Rates of in-hospital stroke, postoperative myocardial infarction, prolonged length of stay (>2 days), and use of intravenous blood pressure medications all varied significantly across the regions. After CEA, there was significant variation in the rates of cranial nerve injuries (asymptomatic, 0.9%-4.9% [P < .01]; symptomatic, 1.5%-7.7% [P < .01]), return to the operating room (asymptomatic, 0.9%-3.4% [P < .01]; symptomatic, 0.6%-3.4% [P = .02]), and discharge on antiplatelet and statin (asymptomatic, 75%-87% [P < .01]; symptomatic, 78%-91% [P < .01]). After CAS, significant variation was found in the rates of access site complications (asymptomatic, 2.3%-18.2% [P < .01]; symptomatic, 1.4%-16.9% [P < .01]) and discharge on dual antiplatelet therapy (asymptomatic, 79%-94% [P < .01]; symptomatic, 83%-93% [P < .01]).

CONCLUSIONS

Unwarranted regional variation exists in outcomes after carotid artery revascularization across the regions of the VQI. Significant variation was seen in a number of outcomes for which quality metrics currently exist, such as length of stay and discharge medications. In addition, after CAS, several regions failed to meet the AHA guidelines for stroke and death. Given these results, quality improvement projects should be targeted to improve adherence to current guidelines to promote best practices.

Factors affecting operative time and outcome of carotid endarterectomy in the Vascular Quality Initiative

OBJECTIVE

Prior studies have suggested a relationship between operative (Op) time and outcome after major vascular procedures. This study analyzed factors associated with Op time and outcome after carotid endarterectomy (CEA) in the Vascular Quality Initiative (VQI) registry.

METHODS

Elective, primary CEAs without high anatomic risk or concomitant procedures from 2012 to 2015 in the VQI were analyzed (N = 26,327, performed by 1188 surgeons from 249 centers). Multivariable analysis was used to identify patient, procedure, and surgeon factors associated with Op time and major adverse events (MAEs), categorized as either technical (ipsilateral stroke, cranial nerve injury, reoperation) or cardiac (myocardial infarction, congestive heart failure, dysrhythmia requiring treatment, surgical site infection, and death).

RESULTS

The mean CEA Op time in the VQI was 114 minutes, with the mean Op time for individual surgeons ranging from 37 to 305 minutes. Procedural factors and the surgeon's volume were responsible for much of the variation in overall Op time (patient factors that reflected demographics and comorbidities each added 5.9 to 6.8 minutes; procedural factors, such as patch angioplasty and completion duplex ultrasound, each added 5.5 to 16.4 minutes; the lowest quartile of the surgeon's annual case volume added 24 minutes). Chi-pie analysis demonstrated that patient factors accounted for 17% of variability in Op time; procedural factors, 44%; and the surgeon's annual volume, 39%. Increasing Op time was highly associated with increased rates of MAEs (P < .001 for cardiac, technical, and death rates). Based on hierarchical multiple logistic regression, cardiac complications were independently associated with increased Op time (comparing surgeons in highest quartile of Op time with those in the lowest: odds ratio, 2.16 for cardiac MAE; 95% confidence interval, 1.59-2.95; P < .001) but not with the surgeon's annual volume. Technical complications were independently associated with a surgeon's low volume (comparing surgeons with the highest annual case volume by quartile against the lowest: odds ratio, 1.25 for technical MAE; 95% confidence interval, 1.06-1.48; P < .001) but not with Op time.

CONCLUSIONS

Op time for elective, primary CEAs varies substantially across surgeons in the VQI. Increased Op time is associated with a surgeon's lower annual CEA volume in addition to patient variables and techniques employed. Cardiac complications after CEA are associated with longer Op time, whereas technical complications are associated with a surgeon's low annual volume.

Regional variation in patient selection and treatment for carotid artery disease in the Vascular Quality Initiative

OBJECTIVE

Previous studies involving large administrative data sets have revealed regional variation in the demographics of patients selected for carotid endarterectomy (CEA) and carotid artery stenting (CAS) but lacked clinical granularity. This study aimed to evaluate regional variation in patient selection and operative technique for carotid artery revascularization using a detailed clinical registry.

METHODS

All patients who underwent CEA or CAS from 2009 to 2015 were identified in the Vascular Quality Initiative (VQI). Deidentified regional groups were used to evaluate variation in patient selection, operative technique, and perioperative management. χ² analysis was used to identify significant variation across regions.

RESULTS

A total of 57,555 carotid artery revascularization procedures were identified. Of these, 49,179 patients underwent CEA (asymptomatic: median, 56%; range, 46%-69%; P < .01) and 8376 patients underwent CAS (asymptomatic: median, 36%; range, 29%-51%; P < .01). There was significant regional variation in the proportion of asymptomatic patients being treated for carotid stenosis <70% in CEA (3%-9%; P < .01) vs CAS (3%-22%; P < .01). There was also significant variation in the rates of intervention for asymptomatic patients older than 80 years (CEA, 12%-27% [P < .01]; CAS, 8%-26% [P < .01]). Preoperative computed tomography angiography or magnetic resonance angiography in the CAS cohort also varied widely (31%-83%; P < .01), as did preoperative medical management with combined aspirin and statin (CEA, 53%-77% [P < .01]; CAS, 62%-80% [P < .01]). In the CEA group, the use of shunt (36%-83%; P < .01), protamine (32%-89%; P < .01), and patch (87%-99%; P < .01) varied widely. Similarly, there was regional variation in frequency of CAS done without a protection device (1%-8%; P < .01).

CONCLUSIONS

Despite clinical benchmarks aimed at guiding management of carotid disease, wide variation in clinical practice exists, including the proportion of asymptomatic patients being treated by CAS and preoperative medical management. Additional intraoperative variables, including the use of a patch and protamine during CEA and use of a protection device during CAS, displayed similar variation in spite of clear guidelines. Quality improvement projects could be directed toward improved adherence to benchmarks in these areas.

Below-Knee Amputation Failure and Poor Functional Outcomes Are Higher Than Predicted in Contemporary Practice

OBJECTIVE

The perceived functional benefit of below-knee amputation (BKA) must be carefully weighed against the need for potential reinterventions. This study sought to examine the contemporary clinical and functional outcomes of patients undergoing BKA in the endovascular era.

METHODS

All patients who underwent BKA from January 2008 to December 2014 at a single tertiary medical center were retrospectively reviewed. Demographics, comorbidities, ambulation status, and transcutaneous oximetry (TcPO2) values were recorded. Study end points included freedom from conversion to above-knee amputation (AKA), freedom from conversion to AKA or death, BKA healing, and ambulation. Statistical modeling was performed to determine associations with BKA failure.

RESULTS

Over the study interval, 130 limbs underwent BKA in 120 patients. Transcutaneous oximetry studies were obtained in 65% (n = 85). Thirty-eight percent (n = 46) of all BKA patients went on to heal and ambulate. Twenty-five percent (n = 33) required reintervention, 24 with conversion to AKA, and 9 with BKA revision. One-year freedom from conversion to AKA was 76% and was decreased among those with lower TcPO2 levels (60% TcPO2 <40 vs 81% TcPO2 ≥40; P = .04). One-year composite freedom from conversion to AKA/death was 60% and was decreased among those with lower TcPO2 readings (39% TcPO2 <40 vs 69% TcPO2 ≥40; P = .01).

CONCLUSION

Despite a perceived functional bias toward knee salvage at the time of major amputation, most patients failed to postoperatively ambulate. Those with decreased TcPO2 levels (<40 mm Hg) have a 2-fold higher risk of AKA conversion or death, while nearly one-fourth of all BKA patients will succumb to the same fate irrespective of TcPO2. This suggests that many BKA patients in the endovascular era fail to derive the perceived benefit of knee salvage at the time of their index amputation. These findings highlight the need for careful patient selection and for a shared decision-making model in this frail population.

The Prevalence and Regional Variation of Major Depressive Disorder Among Patients With Peripheral Arterial Disease in the Medicare Population

Background:

Current evidence suggests an association between coronary artery disease and major depressive disorder (MDD). Data to support a similar association between peripheral arterial disease (PAD) and MDD are more limited. This study examines the prevalence and regional variation of both PAD and MDD in a large contemporary patient sample.

Methods:

All Medicare claims, part A and B, from January 2009 until December 2011 were queried using diagnosis codes specific for a previously validated clinical algorithm for PAD and major depression. Codes for PAD included those specific to cerebrovascular disease, abdominal aortic aneurysm, and peripheral vascular disease. Peripheral arterial disease prevalence, major depression prevalence, and coprevalence rates were determined, respectively. Regional variation of both conditions was determined using zip code data to identify potential endemic areas of disease intensity for both diagnoses.

Results:

Over the study interval, the percentage of Medicare beneficiaries with a diagnosis of PAD remained relatively constant (3.0%-3.7%, n = 0.85-1.06 million in part A and 17.4%-17.5%, n = 4.82-4.93 million in part B), and MDD showed a similar trend (1.6%-2.7%, n = 0.46-0.79 million in part A and 6.1%-6.7%, n = 1.69-1.90 million in part B). The observed rate of MDD in those with an established diagnosis of PAD was 5-fold higher than those without PAD in part A claims (1.8-fold in part B claims). Moreover, there was a significant linear geographic correlation among patients with PAD and MDD ( r = .54, P ≤ .01).

Conclusions:

This study documents a correlation between PAD and MDD and may, therefore, identify an at-risk population susceptible to inferior clinical outcomes. Significant regional variation exists in the prevalence of PAD and MDD, though there appear to be specific endemic regions notable for both disorders. Accordingly, health-care resource allocation toward endemic regions may help improve population health among this at-risk cohort.

Dual antiplatelet therapy reduces stroke but increases bleeding at the time of carotid endarterectomy

OBJECTIVE

Controversy persists regarding the perioperative management of clopidogrel among patients undergoing carotid endarterectomy (CEA). This study examined the effect of preoperative dual antiplatelet therapy (aspirin and clopidogrel) on in-hospital CEA outcomes.

METHODS

Patients undergoing CEA in the Vascular Quality Initiative were analyzed (2003-2014). Patients on clopidogrel and aspirin (dual therapy) were compared with patients taking aspirin alone preoperatively. Study outcomes included reoperation for bleeding and thrombotic complications defined as transient ischemic attack (TIA), stroke, or myocardial infarction. Secondary outcomes were in-hospital death and composite stroke/death. Univariate and multivariable analyses assessed differences in demographics and operative factors. Propensity score-matched cohorts were derived to control for subgroup heterogeneity.

RESULTS

Of 28,683 CEAs, 21,624 patients (75%) were on aspirin and 7059 (25%) were on dual therapy. Patients on dual therapy were more likely to have multiple comorbidities, including coronary artery disease (P < .001), congestive heart failure (P < .001), and diabetes (P < .001). Patients on dual therapy were also more likely to have a drain placed (P < .001) and receive protamine during CEA (P < .001). Multivariable analysis showed that dual therapy was independently associated with increased reoperation for bleeding (odds ratio [OR], 1.71; 95% confidence interval [CI], 1.20-2.42; P = .003) but was protective against TIA or stroke (OR, 0.61; 95% CI, 0.43-0.87; P = .007), stroke (OR, 0.63; 95% CI, 0.41-0.97; P = .03), and stroke/death (OR, 0.66; 95% CI, 0.44-0.98; P = .04). Propensity score matching yielded two groups of 4548 patients and showed that patients on dual therapy were more likely to require reoperation for bleeding (1.3% vs 0.7%; P = .004) but less likely to suffer TIA or stroke (0.9% vs 1.6%; P = .002), stroke (0.6% vs 1.0%; P = .04), or stroke/death (0.7% vs 1.2%; P = .03). Within the propensity score-matched groups, patients on dual therapy had increased rates of reoperation for bleeding regardless of carotid symptom status. However, asymptomatic patients on dual therapy demonstrated reduced rates of TIA or stroke (0.6% vs 1.5%; P < .001), stroke (0.4% vs 0.9%; P = .01), and composite stroke/death (0.5% vs 1.0%; P = .02). Among propensity score-matched patients with symptomatic carotid disease, these differences were not statistically significant.

CONCLUSIONS

Preoperative dual antiplatelet therapy was associated with a 40% risk reduction for neurologic events but also incurred a significant increased risk of reoperation for bleeding after CEA. Given its observed overall neurologic protective effect, continued dual antiplatelet therapy throughout the perioperative period is justified. Initiating dual therapy in all patients undergoing CEA may lead to decreased neurologic complication rates.

Use of a glucose management service improves glycemic control following vascular surgery: an interrupted time-series study

BACKGROUND

The optimal method for obtaining good blood glucose control in noncritically ill patients undergoing peripheral vascular surgery remains a topic of debate for surgeons, endocrinologists, and others involved in the care of patients with peripheral arterial disease and diabetes. A prospective trial was performed to evaluate the impact of routine use of a glucose management service (GMS) on glycemic control within 24 hours of lower-extremity revascularization (LER).

METHODS

In an interrupted time-series design (May 1, 2011-April 30, 2012), surgeon-directed diabetic care (Baseline phase) to routine GMS involvement (Intervention phase) was compared following LER. GMS assumed responsibility for glucose management through discharge. The main outcome measure was glycemic control, assessed by (1) mean hospitalization glucose and (2) the percentage of recorded glucose values within target range. Statistical process control charts were used to assess the impact of the intervention.

RESULTS

Clinically important differences in patient demographics were noted between groups; the 19 patients in the Intervention arm had worse peripheral vascular disease than the 19 patients in the Baseline arm (74% critical limb ischemia versus 58%; p = .63). Routine use of GMS significantly reduced mean hospitalization glucose (191 mg/dL Baseline versus 150 mg/dL Intervention, p < .001). Further, the proportion of glucose values in target range increased (48% Baseline versus 78% Intervention, p = .05). Following removal of GMS involvement, measures of glycemic control did not significantly decrease for the 19 postintervention patients.

CONCLUSIONS

Routine involvement of GMS improved glycemic control in patients undergoing LER. Future work is needed to examine the impact of improved glycemic control on clinical outcomes following LER.

Outcomes of lower extremity revascularization among the hemodialysis-dependent

OBJECTIVE

Optimal patient selection for lower extremity revascularization remains a clinical challenge among the hemodialysis-dependent (HD). The purpose of this study was to examine contemporary real world open and endovascular outcomes of HD patients to better facilitate patient selection for intervention.

METHODS

A regional multicenter registry was queried between 2003 and 2013 for HD patients (N = 689) undergoing open surgical bypass (n = 295) or endovascular intervention (n = 394) for lower extremity revascularization. Patient demographics and comorbidities were recorded. The primary outcome was overall survival. Secondary outcomes included graft patency, freedom from major adverse limb events, and amputation-free survival (AFS). Multivariate analysis was performed to identify independent risk factors for death and amputation.

RESULTS

Among the 689 HD patients undergoing lower extremity revascularization, 66% were male, and 83% were white. Ninety percent of revascularizations were performed for critical limb ischemia and 8% for claudication. Overall survival at 1, 2, and 5 years survival remained low at 60%, 43%, and 21%, respectively. Overall 1- and 2-year AFS was 40% and 17%. Mortality accounted for the primary mode of failure for both open bypass (78%) and endovascular interventions (80%) at two years. Survival, AFS, and freedom from major adverse limb event outcomes did not differ significantly between revascularization techniques. At 2 years, endovascular patency was higher than open bypass (76% vs 26%; 95% confidence interval [CI], 0.28-0.71; P = .02). Multivariate analysis identified age ≥80 years (hazard ratio [HR], 1.9; 95% CI, 1.4-2.5; P < .01), indication of rest pain or tissue loss (HR, 1.8; 95% CI, 1.3-2.6; P < .01), preoperative wheelchair/bedridden status (HR, 1.5; 95% CI, 1.1-2.1; P < .01), coronary artery disease (HR, 1.5; 95% CI, 1.2-1.9; P < .01), and chronic obstructive pulmonary disease (HR, 1.4; 95% CI, 1.1-1.8; P = .01) as independent predictors of death. The presence of three or more risk factors resulted in predicted 1-year mortality of 64%.

CONCLUSIONS

Overall survival and AFS among HD patients remains poor, irrespective of revascularization strategy. Mortality remains the primary driver for these findings and justifies a prudent approach to patient selection. Focus for improved results should emphasize predictors of survival to better identify those most likely to benefit from revascularization.

Lesion complexity drives the cost of superficial femoral artery endovascular interventions

OBJECTIVE

Patients who undergo endovascular treatment of superficial femoral artery (SFA) disease vary greatly in lesion complexity and treatment options. This study examined the association of lesion severity and cost of SFA stenting and to determine if procedure cost affects primary patency at 1 year.

METHODS

A retrospective record review identified patients undergoing initial SFA stenting between January 1, 2010, and February 1, 2012. Medical records were reviewed to collect data on demographics, comorbidities, indication for the procedure, TransAtlantic Inter-Society Consensus (TASC) II severity, and primary patency. The interventional radiology database and hospital accounting database were queried to determine cost drivers of SFA stenting. Procedure supply cost included any item with a bar code used for the procedure. Associations between cost drivers and lesion characteristics were explored. Primary patency was determined using Kaplan-Meier survival curves and a log-rank test.

RESULTS

During the study period, 95 patients underwent stenting in 98 extremities; of these, 61% of SFA stents were performed for claudication, with 80% of lesions classified as TASC II A or B. Primary patency at 1 year was 79% for the entire cohort. The mean total cost per case was $10,333. Increased procedure supply cost was associated with adjunct device use, the number of stents, and TASC II severity. Despite higher costs of treating more complex lesions, primary patency at 1 year was similar at 80% for high-cost (supply cost >$4000) vs 78% for low-cost (supply cost <$4000) interventions.

CONCLUSIONS

SFA lesion complexity, as defined by TASC II severity, drives the cost of endovascular interventions but does not appear to disadvantage patency at 1 year. Reimbursement agencies should consider incorporating disease severity into reimbursement algorithms for lower extremity endovascular interventions.

Domains that Determine Quality of Life in Vascular Amputees

BACKGROUND

Although patients with critical limb ischemia (CLI) commonly undergo major limb amputation, the quality of life (QOL) of this group remains poorly described. Therefore, we sought to describe which domains vascular amputees consider important in determining their health-related QOL.

METHODS

We performed 4 focus groups in patients who had major lower extremity amputations resulting from CLI. They were conducted at 4 distinct centers across the United States to ensure broad geographic, socioeconomic, and ethnic representation.

RESULTS

Of 26 patients (mean age, 64 years), 19 (73%) were Caucasian, 6 (23%) were African American, and 1 (4%) was Native American. Nearly, three-quarter of patients were men (n = 19, 73%) and had a high-school education or more (n = 19, 73%). Overall, 8 (31%) were double amputees and 17 (65%) had diabetes. Time since amputation varied across patients and ranged from 3 months to more than 27 years (mean, 4.3 years). Patients stated that their current QOL was determined by impaired mobility (65%), pain (60%), progression of disease in the remaining limb (55%), and depression/frustration (54%). Across 26 patients, more than half (n = 16, 62%) described multiple prior revascularization procedures. Although most felt that their physician did his/her best to salvage the affected leg (85%), a sizable minority would have preferred an amputation earlier in their CLI treatment course (27%). Furthermore, when asked how their care might have been improved, patients reported that facilitating peer support (88%), more extensive rehabilitation and prosthetist involvement (71%), earlier mention of amputation as a possible outcome (54%), and the early discontinuation of narcotics (54%) were potential areas of improvement.

CONCLUSIONS

Although QOL in vascular amputees seems primarily determined by mobility impairment, pain, and emotional perturbation, our focus groups identified that physician-controlled factors such as the timing of amputation, informed decision making, and postamputation support may also play an important role. The assessment of patient preferences regarding maintenance of mobility at the cost of increased pain versus relief of pain with amputation at a cost of diminished mobility is central to shared decision making in CLI treatment.

Outcomes of carotid endarterectomy versus stenting in comparable medical risk patients

OBJECTIVE

In medically high-risk patients the choice between carotid artery stenting (CAS) and carotid endarterectomy (CEA) can be difficult. The purpose of this study was to compare risk-stratified outcomes of CAS and CEA.

METHODS

Patients who underwent isolated primary CEA (n = 11,336) or primary CAS (n = 544) at 29 centers in the Vascular Study Group of New England were analyzed (2003-2013); patients with previous ipsilateral CEA or CAS, or concomitant coronary artery bypass graft were excluded. A medical risk score based on predicted 5-year mortality was developed for each patient using a Cox proportional hazards model. Patients in the highest risk score quartile were termed high-risk (vs normal-risk for the other three quartiles). Medically high-risk patients had a 5-year survival of 65% and comprised 23% of CEA and 25% of CAS patients. Risk-stratified outcomes were compared within neurologically symptomatic and asymptomatic patients.

RESULTS

Among asymptomatic patients, rates of in-hospital stroke and/or death were not different between CAS and CEA in normal and high-risk cohorts, ranging from 0.7% in normal-risk CEA patients to 1.6% in high-risk CAS patients. In symptomatic patients, significantly worse outcomes were seen with CAS compared with CEA in normal-risk and high-risk patients. Normal-risk symptomatic patients had a stroke or death rate of 1.3% with CEA, but 5.2% with CAS (P < .01). In high-risk symptomatic patients, the stroke or death rate was 1.5% with CEA and 9.3% with CAS (P < .01). No significant differences were seen between asymptomatic CEA and CAS within risk strata across secondary outcome measures of stroke, death, or myocardial infarction, and ipsilateral stroke, major stroke, or death. However, symptomatic high-risk CAS patients had significantly greater rates of all secondary outcomes compared with CEA except death, and symptomatic normal-risk CAS patients had only significantly greater rates of death and stroke, death, or myocardial infarction.

CONCLUSIONS

In the Vascular Study Group of New England, asymptomatic normal- and high-risk patients do equally well after CEA or CAS. However, normal- and high-risk symptomatic patients have substantially worse outcomes with CAS compared with CEA. High medical risk alone might be an insufficient indication for CAS in symptomatic patients.

Designation as "unfit for open repair" is associated with poor outcomes after endovascular aortic aneurysm repair

BACKGROUND

Endovascular aortic aneurysm repair (EVAR) is often offered to patients with abdominal aortic aneurysms (AAAs) considered preoperatively to be unfit for open AAA repair (oAAA). This study describes the short- and long-term outcomes of patients undergoing EVAR with AAAs <6.5 cm who are considered unfit for oAAA.

METHODS AND RESULTS

We analyzed elective EVARs for AAAs <6.5 cm diameter in the Vascular Study Group of New England (2003-2011). Patients were designated as fit or unfit for oAAA by the treating surgeon. End points included in-hospital major adverse events and long-term mortality. We identified patient characteristics associated with being unfit for open repair and predictors of survival using multivariable analyses. Of 1653 EVARs, 309 (18.7%) patients were deemed unfit for oAAA. These patients were more likely to have advanced age, cardiac disease, chronic obstructive pulmonary disease, and larger aneurysms at the time of repair (54 versus 56 mm, P=0.001). Patients unfit for oAAA had higher rates of cardiac (7.8% versus 3.1%, P<0.01) and pulmonary (3.6 versus 1.6, P<0.01) complications and worse survival rates at 5 years (61% versus 80%; log rank P<0.01) compared with those deemed fit for oAAA. Finally, patients designated as unfit for oAAA had worse survival, even adjusting for patient characteristics and aneurysm size (hazard ratio, 1.6; 95% confidence interval, 1.2-2.2; P<0.01).

CONCLUSIONS

In patients with AAAs <6.5 cm, designation by the operating surgeon as unfit for oAAA provides insight into both short- and long-term efficacy of EVAR. Patients unable to tolerate oAAA may not benefit from EVAR unless their risk of AAA rupture is very high.

Functional outcomes following catheter-based iliac vein stent placement

OBJECTIVES

Although previous reports have demonstrated the efficacy of catheter-directed thrombolytic therapy and iliac vein stent placement for the management of iliofemoral deep vein thrombosis (DVT), functional outcomes remain undefined. The purpose of this study was to determine midterm outcomes and functional quality of life among patients treated with iliac vein stenting.

METHODS

Records of all the patients treated with iliac vein stent placement between March 2004 and March 2011 were examined for primary patency, assisted primary patency, and secondary patency. Midterm functional outcomes were measured quantitatively, including ongoing symptoms and return to work status.

RESULTS

Over the study interval, 32 patients (33 limbs) underwent iliac vein stent placement. In all, 72% (n = 23) of these patients were female, with an average age of 43 years. In all, 78% (n = 25) of the patients were diagnosed with acute DVT, 89% of which occurred in the left leg. Catheter-directed thrombolysis was utilized in 92% (23 of 25) of the patients with acute DVT. All patients treated with thrombolysis and stent placement presented with pain and edema in the affected limb. One-year primary, assisted primary, and secondary patencies were 75%, 96%, and 96%, respectively. Freedom from reintervention at 1 year was 83%. Treatment was associated with a sustained significant reduction in pain (91% vs 6%, P < .001) and edema (97% vs 12%, P < .001) at a mean follow-up of 29 months (range 5-83 months), at which time 89% of the patients reported to be at their pre-DVT functional status.

CONCLUSIONS

Aggressive therapy of symptomatic iliac vein stenosis or occlusion with venography, catheter-directed thrombolysis, and iliac vein stent placement provides durable patency and freedom from reintervention. Most patients can anticipate good functional recovery with decreased pain, decreased edema, and high likelihood of returning to work.

Perioperative management with antiplatelet and statin medication is associated with reduced mortality following vascular surgery

OBJECTIVE

Many patients undergoing vascular surgical procedures are not on appropriate medical therapy. This study sought to examine the variation and impact of antiplatelet (AP) and statin therapy on early and late mortality in patients undergoing vascular surgery in our region.

METHODS

We studied all patients (n = 14,489) undergoing elective carotid endarterectomy (n = 6978), carotid stenting (n = 524), and suprainguinal (n = 763) and infrainguinal bypass (n = 3053), as well as patients with known coronary risk factors undergoing open (n = 1044) and endovascular (n = 2127) abdominal aortic aneurysm repair from 2005 to 2012 in the Vascular Study Group of New England. Optimal medical management was defined as treatment with both AP and statin agents, preoperatively and at discharge. We analyzed temporal, procedural, and center variation of medication use. Multivariable analyses were used to determine the adjusted impact of AP and statin therapy on 30-day mortality and 5-year survival.

RESULTS

Optimal medical management improved over the study interval (55% in 2005 to 68% in 2012; P trend < .01) with carotid interventions having the highest rates of optimal medications use (carotid artery stenting, 78%; carotid endarterectomy, 74%) and abdominal aortic aneurysm repair in patients with known cardiac risk factors having the lowest (open, 57%; endovascular aneurysm repair, 56%). Optimal medication use varied by center as well (range, 40%-86%). Preoperative AP and statin use was associated with reduced 30-day mortality (odds ratio, 0.76; 95% confidence interval [CI], 0.5-1.05; P = .09). AP and statin prescription at discharge was additive in survival benefit with improved 5-year survival (hazard ratio, 0.5; 95% CI, 0.4-0.7; P < .01) that was consistent across procedure types. Patients prescribed AP and statin at discharge had 5-year survival of 79% (95% CI, 77%-81%) compared with only 61% (95% CI, 52%-68%; P < .001) for patients on neither medication.

CONCLUSIONS

AP and statin therapy preoperatively and at discharge was associated with reduced 30-day mortality and an absolute 18% improved 5-year survival after vascular surgery. However, one-third of patients are suboptimally managed in real world practice. This demonstrates an opportunity for quality improvement that can substantially improve survival after vascular surgery.

Growing impact of restenosis on the surgical treatment of peripheral arterial disease

Background

Patients with peripheral arterial disease often experience treatment failure from restenosis at the site of a prior peripheral endovascular intervention (PVI) or lower extremity bypass (LEB). The impact of these treatment failures on the utilization and outcomes of secondary interventions is poorly understood.

Methods and Results

In our regional vascular quality improvement collaborative, we compared 2350 patients undergoing primary infrainguinal LEB with 1154 patients undergoing secondary infrainguinal LEB (LEB performed after previous revascularization in the index limb) between 2003 and 2011. The proportion of patients undergoing secondary LEB increased by 72% during the study period (22% of all LEBs in 2003 to 38% in 2011, P<0.001). In‐hospital outcomes, such as myocardial infarction, death, and amputation, were similar between primary and secondary LEB groups. However, in both crude and propensity‐weighted analyses, secondary LEB was associated with significantly inferior 1‐year outcomes, including major adverse limb event‐free survival (composite of death, new bypass graft, surgical bypass graft revision, thrombectomy/thrombolysis, or above‐ankle amputation; Secondary LEB MALE‐free survival = 61.6% vs primary LEB MALE‐free survival = 67.5%, P=0.002) and reintervention or amputation‐free survival (composite of death, reintervention, or above‐ankle amputation; Secondary LEB RAO‐free survival = 58.9% vs Primary LEB RAO‐free survival 64.1%, P=0.003). Inferior outcomes for secondary LEB were observed regardless of the prior failed treatment type (PVI or LEB).

Conclusions

In an era of increasing utilization of PVI, a growing proportion of patients undergo LEB in the setting of a prior failed PVI or surgical bypass. When caring for patients with peripheral arterial disease, physicians should recognize that first treatment failure (PVI or LEB) affects the success of subsequent revascularizations.

The financial implications of endovascular aneurysm repair in the cost containment era

OBJECTIVE

Endovascular aneurysm repair (EVAR) is associated with significant direct device costs. Such costs place EVAR at odds with efforts to constrain healthcare expenditures. This study examines the procedure-associated costs and operating margins associated with EVAR at a tertiary care academic medical center.

METHODS

All infrarenal EVARs performed from April 2011 to March 2012 were identified (n = 127). Among this cohort, 49 patients met standard commercial instruction for use guidelines, were treated using a single manufacturer device, and billed to Medicare diagnosis-related group (DRG) 238. Of these 49 patients, net technical operating margins (technical revenue minus technical cost) were calculated in conjunction with the hospital finance department. EVAR implant costs were determined for each procedure. DRG 238-associated costs and length of stay were benchmarked against other academic medical centers using University Health System Consortium 2012 data.

RESULTS

Among the studied EVAR cohort (age 75, 82% male, mean length of stay, 1.7 days), mean technical costs totaled $31,672. Graft implants accounted for 52% of the allocated technical costs. Institutional overhead was 17% ($5495) of total technical costs. Net mean total technical EVAR-associated operating margins were -$4015 per procedure. Our institutional costs and length of stay, when benchmarked against comparable centers, remained in the lowest quartile nationally using University Health System Consortium costs for DRG 238. Stent graft price did not correlate with total EVAR market share.

CONCLUSIONS

EVAR is currently associated with significant negative operating margins among Medicare beneficiaries. Currently, device costs account for over 50% of EVAR-associated technical costs and did not impact EVAR market share, reflecting an unawareness of cost differential among surgeons. These data indicate that EVAR must undergo dramatic care delivery redesign for this practice to remain sustainable.

Clinical relevance of cranial nerve injury following carotid endarterectomy

OBJECTIVES

The benefit of carotid endarterectomy (CEA) may be diminished by cranial nerve injury (CNI). Using a quality improvement registry, we aimed to identify the nerves affected, duration of symptoms (transient vs. persistent), and clinical predictors of CNI.

METHODS

We identified all patients undergoing CEA in the Vascular Study Group of New England (VSGNE) between 2003 and 2011. Surgeon-observed CNI rate was determined at discharge (postoperative CNI) and at follow-up to determine persistent CNI (CNIs that persisted at routine follow-up visit). Hierarchical multivariable model controlling for surgeon and hospital was used to assess independent predictors for postoperative CNI.

RESULTS

A total of 6,878 patients (33.8% symptomatic) were included for analyses. CNI rate at discharge was 5.6% (n = 382). Sixty patients (0.7%) had more than one nerve affected. The hypoglossal nerve was most frequently involved (n = 185, 2.7%), followed by the facial (n = 128, 1.9%), the vagus (n = 49, 0.7%), and the glossopharyngeal (n = 33, 0.5%) nerve. The vast majority of these CNIs were transient; only 47 patients (0.7%) had a persistent CNI at their follow-up visit (median 10.0 months, range 0.3-15.6 months). Patients with perioperative stroke (0.9%, n = 64) had significantly higher risk of CNI (n = 15, CNI risk 23.4%, p < .01). Predictors for CNI were urgent procedures (OR 1.6, 95% CI 1.2-2.1, p < .01), immediate re-exploration after closure under the same anesthetic (OR 2.0, 95% CI 1.3-3.0, p < .01), and return to the operating room for a neurologic event or bleeding (OR 2.3, 95% CI 1.4-3.8, p < .01), but not redo CEA (OR 1.0, 95% CI 0.5-1.9, p = .90) or prior cervical radiation (OR 0.9, 95% CI 0.3-2.5, p = .80).

CONCLUSIONS

As patients are currently selected in the VSGNE, persistent CNI after CEA is rare. While conditions of urgency and (sub)acute reintervention carried increased risk for postoperative CNI, a history of prior ipsilateral CEA or cervical radiation was not associated with increased CNI rate.

Abstract 323: Regional Variation in Patient Selection for Endovascular vs. Open Abdominal Aortic Aneurysm Repair

Objective: The purpose of this study was to analyze the factors that influence the choice of endovascular (EVAR) vs. open (OAAA) strategies for AAA repair, and examine how this decision varies between centers performing AAA repair in New England.

Methods: We examined prospectively collected data from 2,940 elective infrarenal AAA repairs (985 OAAAs and 1,955 EVARs) performed in 18 centers (2003-2011). All patients were anatomically acceptable candidates for either EVAR or OAAA. We identified pre-operative patient characteristics associated with treatment with EVAR (vs. OAAA repair), adjusting for year. The observed to expected ratio for EVAR utilization was compared across centers.

Results: Overall, EVAR utilization increased from 51% of all repairs in 2003 to 84% of all repairs in 2011 (p<0.001). EVAR utilization varied across centers, from 25 % of all repairs in one center , to 100% of all repairs in other centers (p<0.001). In multivariable analysis, factors associated with choosing EVAR for were increasing age over 65 (HR 1.6, p<0.01), male gender (HR 1.6, p<0.01), diabetes (HR 1.5, p=0.02), CAD (HR 1.5, p=0.01), CHF (HR 2.6, p<0.01), and COPD (HR 1.5, p<0.01). Even after adjustment for these factors, three centers performed EVAR at rates lower than expected (based on patient characteristics alone), and two centers performed EVAR at rates higher than expected ( p<0.05, Figure). In chi-pie analysis, 53 % of the observed variability in EVAR utilization was attributable to center variation and year of repair, while 47% was attributable to differences in patient characteristics.

Conclusion: Hospital practice patterns and adaption to technology influence the decision to perform EVAR more than patient characteristics, and many patients eligible for EVAR still undergo open repair in certain centers. Patients and providers interested in EVAR, irrespective of their anatomy, should seek out repair at centers most likely to perform these procedures.

Optimal selection of asymptomatic patients for carotid endarterectomy based on predicted 5-year survival

OBJECTIVE

Although carotid endarterectomy (CEA) is performed to prevent stroke, long-term survival is essential to ensure benefit, especially in asymptomatic patients. We examined factors associated with 5-year survival following CEA in patients with asymptomatic internal carotid artery (ICA) stenosis.

METHODS

Prospectively collected data from 4114 isolated CEAs performed for asymptomatic stenosis across 24 centers in the Vascular Study Group of New England between 2003 and 2011 were used for this analysis. Late survival was determined with the Social Security Death Index. Cox proportional hazard models were used to identify risk factors for mortality within the first 5 years after CEA and to calculate a risk score for predicting 5-year survival.

RESULTS

Overall 3- and 5-year survival after CEA in asymptomatic patients were 90% (95% CI 89%-91%) and 82% (95% CI 81%-84%), respectively. By multivariate analysis, increasing age, diabetes, smoking history, congestive heart failure, chronic obstructive pulmonary disease, poor renal function (estimated glomerular filtration rate <60 or dialysis dependence), absence of statin use, and worse contralateral ICA stenosis were all associated with worse survival. Patients classified as low (27%), medium (68%), and high risk (5%) based on number of risk factors had 5-year survival rates of 96%, 80%, and 51%, respectively (P < .001).

CONCLUSIONS

More than four out of five asymptomatic patients selected for CEA in the Vascular Study Group of New England achieved 5-year survival, demonstrating that, overall, surgeons in our region selected appropriate patients for carotid revascularization. However, there were patients selected for surgery with high risk profiles, and our models suggest that the highest risk patients (such as those with multiple major risk factors including age ≥ 80, insulin-dependent diabetes, dialysis dependence, and severe contralateral ICA stenosis) are unlikely to survive long enough to realize a benefit of prophylactic CEA for asymptomatic stenosis. Predicting survival is important for decision making in these patients.