Outcomes Of Critical Limb Ischemia Research Articles

Risks and outcomes of critical limb ischemia in hemodialysis patients: a prospective cohort study.

Peripheral arterial disease (PAD) is more common in patients receiving maintenance hemodialysis than in the general population. Critical limb ischemia (CLI), the most severe form of PAD, is associated with high amputation and mortality risk. However, few prospective studies are available evaluating this disease's presentation, risk factors and outcomes for patients receiving hemodialysis. The Hsinchu VA study, a prospective multicentre study, investigated the impact of clinical factors on cardiovascular outcomes of patients receiving maintenance hemodialysis from January 2008 until December 2021. We evaluated the presentations and outcomes of patients with newly diagnosed PAD and the correlations of clinical variables with newly diagnosed CLI. Of 1136 study participants, 1038 had no PAD on enrolment. After a median follow-up period of 3.3 years, 128 had newly diagnosed PAD. Of these, 65 presented with CLI, and 25 underwent amputation or died from PAD. Patients presenting with CLI had more below-the-knee (52%) and multi-level (41%) disease, and completely occluded segments (41%), and higher risk for amputation or PAD-related death compared with patients without CLI (27.7%vs 9.5%, P=.01). After multivariate adjustment, disability, diabetes mellitus, current smoking and atrial fibrillation were significantly associated with newly diagnosed CLI. Patients undergoing hemodialysis had higher rates of newly diagnosed CLI than the general population. Those with disabilities, diabetes mellitus, smoking and atrial fibrillation may require careful examination for PAD. Trial registration: Hsinchu VA study, ClinicalTrials.gov identifier: NCT04692636.

Differences Between Patients With Intermittent Claudication and Critical Limb Ischemia Undergoing Endovascular Intervention: Insights From the Excellence in Peripheral Artery Disease Registry.

There are limited data on differences in angiographic distribution of peripheral artery disease and endovascular revascularization strategies in patients presenting with intermittent claudication (IC) and critical limb ischemia (CLI). We aimed to compare anatomic features, treatment strategies, and clinical outcomes between patients with IC and CLI undergoing endovascular revascularization. We examined 3326 patients enrolled in the Excellence in Peripheral Artery Disease registry from 2006 to 2019 who were referred for endovascular intervention for IC (n=1983) or CLI (n=1343). The primary outcome was 1-year major adverse limb events, which included death, repeat target limb revascularization, or target limb amputation. Patients with CLI were older and more likely to have diabetes and chronic kidney disease and less likely to receive optimal medical therapy compared with IC. Patients with IC had higher femoropopliteal artery interventions (IC 87% versus CLI 65%; P<0.001), while below the knee interventions were more frequent in CLI (CLI 47% versus IC 12%; P<0.001). Patients with CLI were more likely to have multilevel peripheral artery disease (CLI 32% versus IC 15%, P<0.001). Patients with IC were predominantly revascularized with stents (IC 48% versus CLI 37%; P<0.001) while balloon angioplasty was more frequent in CLI (CLI 37% versus IC 25%; P<0.001). All-cause mortality was higher in patients with CLI (CLI 4% versus IC 2%; P=0.014). Major adverse limb event rates for patients with IC and CLI were 16% and 26%, respectively (P<0.001) and remained higher in CLI after multivariable adjustment of baseline risk factors. Patients with IC and CLI have significant anatomic, lesion, and treatment differences with significantly higher mortality and adverse limb outcomes in CLI. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01904851. Graphic Abstract: A graphic abstract is available for this article.

The association of malnutrition with mortality and amputation outcomes in critical limb ischemia: a systematic review

Abstract Introduction Critical limb ischemia (CLI) is a severe stage of peripheral arterial disease with high mortality. Malnutrition has been recognized as a potentially modifiable risk factor that may be prognostic of mortality and amputation outcomes in CLI. Great variability exists in the measurement of malnutrition including surrogate markers such as albumin level and body mass index (BMI) but also validated tools including geriatric nutritional risk index (GNRI) and controlling nutritional status (CONUT). Purpose To conduct a systematic review examining the association of malnutrition with mortality and amputation outcomes in patients with CLI. Methods A systematic literature search of AMED, CINAHL, Cochrane Library, Medline, Embase, Pubmed, Scopus, Web of Science, and Google Scholar was conducted through September 12, 2020. The review protocol was registered in PROSPERO. Only CLI patients were included. It was limited by adult human studies and those after 1982, when CLI was first defined. Eligible studies were randomized controlled trials, cohort studies, and case-control studies while case series, case reports, editorials, conference abstracts, and non-English studies were excluded. Malnutrition measured by albumin, BMI, or a validated malnutrition assessment tool was included. Outcomes of interest were mortality, any amputation, amputation free survival (AFS), major adverse limb events (MALE), major adverse cardiovascular events (MACE), or a composite of these. Two reviewers independently performed screening, data extraction, and quality assessment with a third independent reviewer resolving disagreements. Results 3290 initial studies were found. The final 33 eligible studies were from 7 countries published between 2002 to 2020. Of these 30 were retrospective cohort studies, three were prospective cohort studies, and none were randomized controlled trials. No studies were at serious or critical risk of bias by evaluation with ROBINS-I quality tool. The average sample size was 553 patients (range N=21–5110). The median age was 72 years and 67.1% were male. The prognostic association of malnutrition and outcomes varied by malnutrition tool used. Malnutrition as measured by the validated tools of GNRI and CONUT was associated with all mortality outcomes, except for GNRI and cardiovascular mortality. The malnutrition surrogate markers of albumin and BMI were only associated with mortality outcomes in 62.5–75% of results. The validated nutrition tools were also consistently prognostic of amputation outcomes in all results, whereas surrogate markers only in 62.5–67%. Overall malnutrition by validated tools was prognostic in 14/15 (93.3%) of results while surrogate markers in 29/42 (69%) of results. See table 1. Conclusion Malnutrition is prognostically associated with mortality and amputation outcomes in CLI. This association is most consistent when malnutrition is assessed by a validated tool. Funding Acknowledgement Type of funding sources: None.

Endothelial function in patients with critical and non-critical limb ischemia undergoing endovascular treatment.

Critical limb ischemia (CLI) is the most advanced stage of peripheral arterial disease. CLI patients, compared to non-CLI, achieve worse treatment outcomes and generate higher costs. The aim of the study was to compare endothelial function and clinical outcomes in CLI and non-CLI patients after percutaneous transluminal angioplasty (PTA). In this prospective, follow-up study, 30 CLI patients and 40 non-CLI patients underwent PTA. Endothelial function was assessed based on flow mediated dilatation (FMD), reactive-hyperemia index (RHI), while the ankle-brachial index, toe-brachial index and the Rutherford scale were used for peripheral artery disease progression evaluation. The results were assessed before PTA, as well as 1, 3, 6 and 12 months after the procedure. There were no differences at the baseline regarding to endothelial function between both groups. Neither FMD nor RHI changed after PTA in any of the groups, although there was a difference in median RHI value between CLI and non-CLI patients regarding the 1st and 6th month of the follow-up (RHI6-RHI1 = 0.08 in CLI and -0.15 in non-CLI; P = 0.01). The larger baseline intima-media thickness (IMT) in the CLI group allowed to predict a greater number of re-intervention (P = 0.01) and major adverse event rates (P = 0.03). CLI patients presented larger decrease in the Rutherford scale compared to non-CLI (P <0.001). Baseline IMT was predictive for re-interventions and major adverse event rates. Although neither of groups exhibited significant changes in endothelial function, we proved differences between them regarding to changes in RHI.

Neutrophil-to-lymphocyte ratio associated with an increased risk of mortality in patients with critical limb ischemia.

Association of the neutrophil-to-lymphocyte ratio (NLR) with mortality has not been comprehensively explored in critical limb ischemia (CLI) patients. We investigated the association between the NLR and clinical outcomes in CLI. We retrospectively enrolled consecutive CLI patients between 1/1/2013 and 12/31/2018. Receiver operating characteristic curve analysis determined NLR cutoffs for 1-year in-hospital, all-cause and cardiac-related mortality; major adverse cardiovascular events (MACEs); and major adverse limb events (MALEs). Among 195 patients (age, 74.0 years, SD: 11.5; 51.8% male; body mass index, 23.4 kg/m2, SD: 4.2), 14.4% exhibited acute limb ischemia. After 1 year, patients with NLR>8 had higher in-hospital mortality (21.1% vs. 3.6%, P<0.001), all-cause mortality (54.4% vs. 13.8%, P<0.001), cardiac-related mortality (28.1% vs. 6.5%, P<0.001), MACE (29.8% vs. 13.0%, P = 0.008), and MALE (28.1% vs. 13.0%, P = 0.021) rates than those with NLR<8. In multivariate logistic regression, NLR≥8 was significantly associated with all-cause (P<0.001) and cardiac-related (adjusted HR: 5.286, 95% CI: 2.075-13.47, P<0.001) mortality, and NLR≥6 was significantly associated with MALEs (adjusted HR: 2.804, 95% CI: 1.292-6.088, P = 0.009). Each increase in the NLR was associated with increases in all-cause (adjusted HR: 1.028, 95% CI: 1.008-1.049, P = 0.007) and cardiac-related (adjusted HR:1.027, 95% CI: 0.998-1.057, P = 0.073) mortality but not in-hospital mortality or MACEs. CLI patients with high NLRs had significantly higher risks of 1-year all-cause and cardiac-related mortality and MALEs. The NLR can be used for prognostic prediction in these patients.

Temporal trends and outcomes of critical limb ischemia among patients with chronic kidney disease.

There is a paucity of data on the outcomes and revascularization strategies for critical limb ischemia (CLI) among patients with chronic kidney disease (CKD). Hence, we conducted a nationwide analysis to evaluate the trends and outcomes of hospitalizations for CLI with CKD. The National Inpatient Sample database (2002-2015) was queried for hospitalizations for CLI. The trends of hospitalizations for CLI with CKD were reported, and endovascular versus surgical revascularization strategies for CLI with CKD were compared. The main study outcome was in-hospital mortality. The analysis included 2,139,640 hospitalizations for CLI, of which 484,224 (22.6%) had CKD. There was an increase in hospitalizations for CLI with CKD (Ptrend = 0.01), but a reduction in hospitalizations for CLI without CKD (Ptrend = 0.01). Patients with CLI and CKD were less likely to undergo revascularization compared with patients without CKD. CLI with CKD had higher rates of in-hospital mortality (4.8% vs 2.5%, adjusted odds ratio (OR) 2.01; 95% CI 1.93-2.11) and major amputation compared with no CKD. Revascularization for CLI with CKD was associated with lower rates of mortality (3.7% vs 5.3%, adjusted-OR 0.78; 95% CI 0.72-0.84) and major amputation compared with no revascularization. Compared with endovascular revascularization, surgical revascularization for CLI with CKD was associated with higher rates of in-hospital mortality (4.7% vs 2.7%, adjusted-OR 1.67; 95% CI 1.43-1.94). In conclusion, this contemporary observational analysis showed an increase in hospitalizations for CLI among patients with CKD. CLI with CKD was associated with higher in-hospital mortality compared with no CKD. Compared with endovascular therapy, surgical revascularization for CLI with CKD was associated with higher in-hospital mortality.

Gender Disparities in Presentation, Treatment, and Outcomes of Critical Limb Ischemia

Women with peripheral artery disease (PAD) experience higher rates of functional decline and may have worse clinical outcomes after invasive treatment for PAD compared to men. Despite this, women remain under-represented in contemporary PAD studies. We aim to use National Surgical Quality Improvement Program data to better understand differences in presentation, treatment, and short-term outcomes for women compared to men undergoing lower extremity (LE) revascularization for critical limb ischemia (CLI). We included 2018 patients. The National Surgical Quality Improvement Program database includes 30-day outcomes for inpatient operations at participating hospitals. Descriptive statistics and multivariable analyses were performed. There were a total of 32,902 LE interventions, of which 22,111 (67%) were for patients with CLI (rest pain or tissue loss). Women were significantly more likely to have CLI on presentation (71% vs 65%; P < .001) compared to men. In the cohort of patients undergoing LE intervention for CLI, women were more likely to be older (mean, 70 ± 12 years vs 68 ± 11 years; P < .001), black (25% vs 18%; P < .001), and hypertensive (86% vs 82%; P < .001), and less likely to be smokers (31% vs 38%; P < .001), on a statin medication (69% vs 71%; P < .001), or functionally independent (84% vs 89%; P < .001). Women were more likely to have a preoperative ankle-brachial index of <0.4 (20% vs 16%; P < .001) compared to men (Table I). Women with CLI were more likely to undergo endovascular intervention compared to men (44% vs 38%; P < .001) and were less likely to have distal/tibial artery revascularization (Table I). Women who underwent open operations had a higher risk of surgical site infection (odds ratio [OR], 1.45; 95% confidence interval [CI], 1.3-1.6) and 30-day reintervention (OR, 1.2; 95% CI, 1.01-1.4) compared to men (Table II). Men with CLI who underwent endovascular intervention were more likely to undergo a major amputation within 30 days compared to women (OR, 1.3; 95% CI, 1.1-1.6). Overall, women had a higher risk of postoperative myocardial infarction (MI) and death compared to men (OR, 1.2; 95% CI, 1.02-1.4). Women undergoing LE revascularization for CLI are older, present with more advanced ischemia, and are more likely to undergo endovascular intervention compared to men. Despite increased use of less invasive strategies to treat CLI, women have higher rates of 30-day death and MI. Women with cardiovascular risk factors may benefit from more aggressive screening and medical treatment for PAD in order to mitigate the negative consequences of CLI.Table IBaseline patient and operative characteristicsFemale n = 8441Male n = 13,670P valueAge in years, mean (SD)70 (12)68 (11)<.001Race<.001 White4964 (59%)8944 (65%) Black or African American2078 (25%)2416 (18%) Other/unknown1399 (17%)2310 (17%)Diabetes4536 (54%)7619 (56%).004Hypertension7238 (86%)11,262 (82%)<.001Dialysis828 (10%)1450 (11%).06Smoking2635 (31%)5121 (38%)<.001Preoperative aspirin6804 (81%)10,974 (81%).55Preoperative statin5763 (69%)9684 (71%)<.001Preoperative beta-blocker5104 (61%)8369 (62%).23Preoperative function status<.001 Independent7122 (84%)12,196 (89%) Partially dependent1148 (14%)1256 (9%) Totally dependent118 (1%)134 (1%)Preoperative ABI <0.41698 (20%)2239 (16%)<.001Prior ipsilateral intervention3401 (40.3%)5146 (37.6%)<.001Open Intervention4717 (56%)8531 (62%)<.001 Operation type<.001Femoral popliteal bypass2623 (56%)3997 (47%)Femoral distal bypass1521 (32%)3152 (37%)Popliteal distal bypass435 (9%)1060 (13%)Femoral endarterectomy51 (1%)105 (1%) Conduit<.001Single segment vein2309 (49%)4411 (52%)Prosthetic/spliced vein2270 (48%)3798 (45%)Endovascular intervention3724 (44%)5139 (38%)<.001 Operation type<.001Femoral/popliteal angioplasty/stent2831 (77%)3362 (66%)Tibial angioplasty/stent867 (23%)1739 (34%)Operative time in minutes, mean (SD)186 (117)200 (121)<.001ABI, Ankle-brachial index; SD, standard deviation. Open table in a new tab Table IIThirty-day outcomesOpenEndovascularFemale n = 4717Male n = 8531P valueFemale n = 3724Male n = 5139P valueMyocardial infarction183 (3.9%)287 (3.3%)0.1284 (2.3%)92 (1.8%).12Surgical site infection496 (10.5%)639 (7.5%)<.00151 (1.4%)61 (1.2%).45Reintervention290 (6.1%)449 (5.3%)0.034152 (4.1%)258 (5.0%).038Major amputation209 (4.4%)375 (4.4%)0.93162 (4.4%)296 (5.8%).003Death77 (1.6%)119 (1.4%)0.2855 (1.5%)69 (1.3%).60 Open table in a new tab

&lt;p&gt;One-Year Outcomes of Peripheral Endovascular Device Intervention in Critical Limb Ischemia Patients: Sub-Analysis of the LIBERTY 360 Study&lt;/p&gt;

BackgroundHigh-risk patients with advanced peripheral artery disease (PAD), including critical limb ischemia (CLI), are often excluded from peripheral endovascular device intervention clinical trials, leading to difficulty in translating trial results into real-world practice. There is a need for prospectively assessed studies to evaluate peripheral endovascular device intervention outcomes in CLI patients.MethodsLIBERTY 360 is a prospective, observational, multi-center study designed to evaluate the procedural and long-term clinical outcomes of peripheral endovascular device intervention in real-world patients with symptomatic lower-extremity PAD. One thousand two hundred and four patients were enrolled and stratified based on Rutherford Classification (RC): RC2-3 (N=501), RC4-5 (N=603), and RC6 (N=100). For this sub-analysis, RC5 and RC6 patients (RC5-6; N=404) were pooled and 1-year outcomes were assessed.ResultsProcedural complications rarely (1.7%) resulted in post-procedural hospitalization and 89.1% of RC5-6 patients were discharged to home. Considering the advanced disease state in RC5-6 patients, there was a high freedom from 1-year major adverse event rate of 65.5% (defined as target vessel revascularization, death to 30 days, and major target limb amputation). At 1 year, freedom from major amputation was 89.6%. Wounds identified at baseline on the target limb had completely healed in 172/243 (70.8%) of the RC5-6 subjects by 1 year. Additionally, the overall quality of life, as measured by VascuQoL, improved from baseline to 1 year.ConclusionLIBERTY investigated real-world PAD patients with independent oversight of outcomes. This analysis of LIBERTY RC5-6 patients demonstrates that peripheral endovascular device intervention can be successful in CLI patients, with low rates of major amputation and improvement in wound healing and quality of life through 1-year follow-up.LIBERTY 360, https://clinicaltrials.gov/ct2/show/NCT01855412, ClinicalTrials.gov Identifier: NCT01855412.

Trends in Hospitalization, Management, and Clinical Outcomes Among Veterans With Critical Limb Ischemia.

Contemporary patterns in management and outcomes of critical limb ischemia among United States veterans are unknown. We used Veterans Health Administration data to identify patients admitted for critical limb ischemia between 2005 and 2014. We examined temporal trends in incidence, management, and outcomes. A total of 20 938 veterans with critical limb ischemia were hospitalized between 2005 and 2014. Mean age was 67.8 years. Incidence decreased from 0.3 to 0.24 per 1000 persons from 2005 to 2013, P<0.01. During the study period, there was a temporal increase in use of revascularization within 90 days of hospitalization-endovascular (11.2% in 2005 to 18.4% in 2014), surgical (23.8% in 2005 to 26.4% in 2014), and hybrid (6.2% in 2005 to 13.1% in 2014, P value for trend <0.01). Statin prescriptions increased from 47.4% in 2005 to 60.9% in 2014 (P value for trend <0.01). There was a significant decline in risk-adjusted mortality (11.8% in 2005 to 9.7% in 2014) and major amputation (19.8% in 2005 to 12.9% in 2014; P value for trend <0.01 for both) at 90 days. In adjusted analyses, revascularization was associated with a lower risk of mortality (RR, 0.45 [95% CI, 0.41-0.50]; P<0.001) and major amputation at 90 days (RR, 0.23 [95% CI, 0.21-0.26]; P<0.001). Nearly half of the patients who underwent amputation did not receive an invasive vascular procedure within the preceding 90 days. There was large site-level variation in the use of revascularization (median rate, 41.7% [interquartile range, 12.5%-53.2%]). Differences in patient case-mix explained only 8% of site-level variation in receipt of revascularization. Over the past decade, use of revascularization increased among veterans with critical limb ischemia, which was accompanied by a reduction in mortality and major amputation. However, opportunities to further improve care in this high-risk population still remain.

TCT-571 Glasgow Prognostic Score Predicts the Clinical Outcomes in Critical Limb Ischemia With Tissue Loss After Endovascular Treatment

TCT-571 Glasgow Prognostic Score Predicts the Clinical Outcomes in Critical Limb Ischemia With Tissue Loss After Endovascular Treatment

IMPACT OF HYPERTENSION ON LONG-TERM CLINICAL OUTCOME IN PATIENTS WITH CRITICAL LIMB ISCHEMIA UNDERGOING BELOW-THE –KNEE INTERVENTION

Objective:Hypertension (HTN) is an independent predictors of adverse clinical outcomes in patients with coronary artery disease receiving percutaneous coronary intervention (PCI). However, the effects of HTN on long-term clinical outcomes in critical limb ischemia (CLI) undergoing are still unclear.

P3570Impact of nutritional status on clinical outcomes in critical limb ischemia with tissue loss after endovascular treatment

P3570Impact of nutritional status on clinical outcomes in critical limb ischemia with tissue loss after endovascular treatment

Impact of infection severity on clinical outcomes in critical limb ischemia with tissue loss after endovascular treatment.

Critical limb ischemia with infected wounds is known to have a poor prognosis and evaluation of infection severity using the Wound, Ischemia, and foot Infection classification system has been recommended. However, little is known about how infection severity influences the clinical outcomes of critical limb ischemia in patients with tissue loss. We investigated the impact of infection severity on the clinical outcomes in critical limb ischemia with tissue loss after endovascular treatment. In April 2007-August 2014, we enrolled 263 patients (328 limbs) who received endovascular treatment for critical limb ischemia with tissue loss. In the limbs examined, 369 individual wounds existed. We evaluated wound infection using the Infectious Disease Society of America (IDSA) classification. We also investigated wound healing rates at 12months and limb salvage and major amputation-free survival rates at 2years after endovascular treatment. Wound healing rates at 12months for class 0, 1, 2, and 3 were 89, 81, 58, and 33%, respectively (log rank P < 0.001). Limb salvage and major amputation-free survival rates at 2years were lower in patients with lower vs. higher IDSA classes (classes 0-3: limb salvage rate: 97, 90, 61, and 0%, respectively; P < 0.001; major amputation-free survival: 67, 61, 38, and 0%, respectively; P < 0.001). In Rutherford category 5, only wound healing rates at 12months and limb salvage and major amputation-free survival rates at 2years were stratified according to wound infection severity (wound healing rates: 87% in classes 0 and 1 and 65% in classes 2 and 3; P < 0.001; limb salvage rates: 93% in classes 0 and 1 and 69% in classes 0 and 2; P < 0.0001; major amputation-free survival rates: 61% in classes 0 and 1 and 46% in classes 2 and 3; P < 0.001). Wound infection severity affects clinical outcomes of critical limb ischemia with tissue loss, especially in critical limb ischemia with systemic inflammatory response syndrome. In Rutherford category 5, only clinical outcomes of critical limb ischemia were well-stratified according to infection severity. Wound infection affects clinical outcomes of patients with critical limb ischemia with tissue loss.

Abstract 728: The Neutrophil-to-lymphocyte Ratio is Associated With Amputation Free Survival in Critical Limb Ischemia

Introduction: Inflammation plays a key role in ischemic cardiovascular disease. The neutrophil-to-lymphocyte ratio (NLR) is an inexpensive marker for inflammation and correlates with outcomes in critical limb ischemia (CLI). Previous studies have suffered from low power due to low event rates, and show only limited adjustment for confounders. We examined in a prospective cohort whether the peripheral blood (PB) NLR predicts amputation-free-survival (AFS) and has additional predictive power over established risk factors. We also studied bone-marrow (BM) composition and plasma cytokines to elucidate the etiology of NLR alterations. Methods and Results: Data from CLI patients in the JUVENTAS Trial and ATHERO-EXPRESS registry were pooled (N=351). Median follow-up was 3.16 years during which 128 events (amputation or death) occurred. In patients that experienced an event, the PB NLR was elevated (Event: 4.2 (SD 2.8) vs No event: 3.0 (SD 1.9) p=&lt;0.001), the neutrophil count was higher (6.3 (SD 2.5) vs 5.5 (SD2.3) p=0.0003), and the lymphocyte count was lower (1.7 (SD 0.8) vs 2.1 (SD 0.8) p&lt;0.001). Cox regression showed that the hazard ratio (HR) for AFS was 1.6 (CI: 1.4-1.9), p=2*10 -8 . In a model adjusting for age, sex, diabetes mellitus, BMI, smoking, and GFR the NLR significantly predicted AFS, HR 1.4 (CI 1.2-1.7) p=0.0003. In a sub study in the JUVENTAS cohort, the PB NLR correlated with the BM NLR, but the BM NLR did not correlate with AFS. Additionally, the NLR correlated strongly with the inflammatory cytokines IL-6, IL-8, and CRP. Discussion and Conclusion: These results show that the NLR is an independent predictor of AFS in CLI. While most studies analyzed the NLR as a binary value, here we show a continuous correlation between the NLR and AFS, even when corrected for major confounders. We show that blood NLR is reflected in BM and correlates with inflammatory cytokines, indicating that our incidental measurements may reflect chronic inflammation-driven alterations in BM.

Analysis of IN.PACT DEEP trial on the association between changes in perfusion from pre- to postrevascularization and clinical outcomes in critical limb ischemia.

To quantify changes in ankle and toe pressure from pre- to post-endovascular revascularization for critical limb ischemia (CLI) and examine their association with major adverse limb events (MALE). Despite societal guidelines recommendation of routine hemodynamic surveillance following revascularization, little is known about hemodynamic assessment in CLI. Among the 358 patients with CLI from the international multicenter IN.PACT DEEP trial, ankle and toe pressures measurements were available at both baseline and after intervention in 270 and 44 patients, respectively. The change in ankle and toe pressures in response to endovascular revascularization and its association with 1-year MALE (target limb revascularization, amputation, or death) were examined using Kaplan-Meier curves and multivariable Cox proportional hazard analyses. Corresponding optimal cutoff points were also identified. The mean increase in ankle and toe pressures following revascularization was 33 and 13 mmHg, respectively. Patients with an improvement of ankle pressure >73 mmHg or toe pressure >1 mmHg had similarly the lowest incidence of MALE (23%), while the highest rate of MALE (50%) was found in those whose toe pressure failed to improve by at least 1 mmHg following intervention. In addition, an increase in ankle pressure >73 mmHg was numerically protective against MALE, and more importantly, an increase in toe pressure of >1 mmHg provided statistically significant protection from MALE (adjusted HR = 0.15, 95% CI: 0.04-0.57, P = 0.005). Improvements in toe pressure post revascularization are incremental and rarely normalize. Toe pressure, compared to ankle pressure, is more useful in CLI and predicts future MALE.

Surgeon, not institution, case volume is associated with limb outcomes after lower extremity bypass for critical limb ischemia in the Vascular Quality Initiative

ObjectiveStudies from large administrative databases have demonstrated associations between institutional case volume and outcomes after lower extremity bypass (LEB). We hypothesized that increased institutional and surgeon volume would be associated with improved outcomes after LEB. Using a national, prospectively collected clinical database, the objective of this study was to determine the effects of both surgeon and institutional volume on outcomes after LEB. MethodsThe Vascular Quality Initiative (VQI) was queried to identify all LEBs for critical limb ischemia or claudication between 2004 and 2014. Average annual case volume was calculated by dividing an institution's or surgeon's total LEB volume by the number of years they reported to the VQI. Institutional and surgeon volumes were analyzed as continuous variables to determine the impact of volume on major adverse cardiac events (MACEs), major adverse limb events (MALEs), graft patency, and amputation-free survival. Hierarchical regression models were used with cases clustered by surgeon and center. Time-dependent outcomes were evaluated with multivariable shared frailty Cox proportional hazards models. ResultsFrom 2004 to 2014, there were 14,678 LEB operations performed at 114 institutions by 587 surgeons. Average annual institutional volume ranged from 1.0 to 137.5 LEBs per year, with a median of 26.9 (interquartile range, 14-45.3). Average annual surgeon volume ranged from 1 to 52 LEBs per year with a median of 5.7 (interquartile range, 2.5-9.3). Institutional LEB volume was not associated with MACEs or MALEs or with loss of patency. However, average annual surgeon volume was independently associated with reduced MALEs and improved primary patency. Institutional and surgeon volume did not predict MACEs. ConclusionsIn contradistinction to previous studies, there was no relationship in this study between institutional LEB volume and outcomes after LEB. However, greater average annual surgeon volume was associated with improved primary patency and decreased risk of MALEs. Open LEB remains a safe and effective procedure for limb salvage. Limb-related outcomes in critical limb ischemia and claudication will be optimized if surgeons maintain adequate volume of LEB.

CRT-300.03 Role of Transthoracic Echocardiography in the Preoperative Evaluation of Patients with Critical Limb Ischemia Undergoing Surgical Bypass

Peripheral surgical bypass for treatment of critical limb ischemia (CLI) is associated with an increased 30-day cardiovascular event rate (8.8% MACE, 1.5% cardiac arrest, 4.7% myocardial infarction, 1.4% stroke and 2.7% death). The purpose of this study is to evaluate 30-day cardiac outcomes in CLI

Arteriographic Patterns of Atherosclerosis and the Association between Diabetes Mellitus and Ethnicity in Chronic Critical Limb Ischemia

Disparate outcomes in critical limb ischemia (CLI) persist between ethnicities. The contribution of modifiable factors versus intrinsic biologic differences remains unclear. Hence, we aimed to quantify the associations between ethnicity and anatomic patterns of arterial occlusive disease in CLI, adjusting for known atherosclerotic risk factors. We performed a retrospective, single-center review of consecutive patients presenting to the vascular surgery service with CLI. Arterial lesions were defined by location (aortoiliac=aorta and iliac arteries; femoral=common, profunda, and superficial femoral arteries; and popliteal-tibial=infrapopliteal and tibial arteries). Stenoses ≥50% were deemed hemodynamically significant. Associations between the patients' baseline arteriographic patterns, demographics, and medical comorbidities were defined using Kruskal-Wallis, χ2, and Mantel-Haenszel χ2 tests. Between August 2010 and January 2014, 286 CLI patients (n=172 male, n=176 tissue loss) were evaluated by the Vascular Surgery service. Two hundred seventy subjects had baseline arteriograms for analysis (black n=134, 50%; Hispanic n=78, 29%; Caucasian n=58, 21%.) All ethnicities presented most frequently with simultaneous disease in all infrainguinal segments (n=124, 46%). Of Hispanics, 30% (n=23) presented with isolated infrapopliteal disease, which was higher than any other ethnic group (P=0.02, χ2). Caucasians (n=8, 14%) presented more frequently with isolated aortoiliac occlusive disease than either Hispanics (n=0, 0%) or blacks (n=2, 1%; P=0.06). Diabetes mellitus was most prevalent among Hispanics (n=72, 85%) relative to blacks (n=77, 55%) and Caucasians (n=32, 52%; P<0.001, χ2). Median hemoglobin A1c (HbA1c) was also highest among Hispanics (7.3%, interquartile range [IQR] 6.2-9.9) versus blacks and Caucasians (6.6%, IQR 5.8-8.2 and 6.0%, IQR 5.6-7.6; P=0.002, Kruskal-Wallis). Tobacco abuse was most frequent among Caucasians (n=53, 87%) and blacks (n=113, 81%). Forty-eight (57%) of Hispanics abused tobacco (P=0.001, χ2.) Subgroup analysis of subjects stratified by baseline HbA1c revealed that there was no relationship between ethnicity and isolated infrapopliteal disease among subjects with HbA1c ≤8.8% (P=0.58, Mantel-Haenszel χ2). Conversely, patients with poorer glycemic control (HbA1c≥8.9%) were more frequently Hispanic and had a higher probability of having isolated infrapopliteal disease (P=0.005, Mantel-Haenszel χ2). Hispanic patients present more frequently with isolated infrapopliteal arterial disease relative to other ethnicities, which may contribute to disparate CLI outcomes. Isolated infrapopliteal disease appears to be driven mostly be poorer glycemic control rather than inherent biologic differences between ethnicities. Future studies aimed at understanding disparate outcomes due to race after lower extremity revascularization may benefit from stratification by the severity of diabetes mellitus. Understanding the distribution of atherosclerotic disease may improve the ability to predict outcomes in limb-threatening ischemia.

Diabetes Is Associated With Decreased Limb Survival in Patients With Critical Limb Ischemia: Pooled Data From Two Randomized Controlled Trials.

Although never assessed prospectively, diabetes mellitus (DM) is assumed to negatively affect the outcomes of critical limb ischemia (CLI). DM was highly prevalent in two recently conducted randomized controlled trials in CLI patients, the PADI (Percutaneous Transluminal Balloon Angioplasty [PTA] and Drug Eluting Stents for Infrapopliteal Lesions in Critical Limb Ischemia) and JUVENTAS (Rejuvenating Endothelial Progenitor Cells via Transcutaneous Intra-Arterial Supplementation) trials. To determine the implications of DM in a population of patients with infrapopliteal CLI, clinical outcomes were compared in patients with and without DM. Individual data from patients with CLI (Rutherford category ≥4) were pooled. Patients were considered to have DM when this diagnosis was reported in the hospital electronic medical records. Rates of major amputation (above ankle level) and major events (major amputation or death) were compared between CLI patients with and without DM. Hazard ratios (HRs) were calculated. Of a total of 281 patients, DM was present in 49.1%. The major amputation rate at 5 years of follow-up was higher in patients with DM than in patients without DM (34.1% vs. 20.4%, P = 0.015). The major event and death rate did not differ. The unadjusted HR of DM for the major amputation risk was 1.87 (95% CI 1.12-3.12). Model factors with significant HRs in the multivariate analysis were baseline Rutherford category (HR 1.95; 95% CI 1.24-3.06) and ankle-brachial index (ABI) >1.4 (HR 2.78; 95% CI 1.37-5.64). CLI patients with DM are at a significantly higher risk of major amputation than CLI patients without DM. This increased risk is associated with a higher prevalence of baseline ABI >1.4 and more severe ischemia at initial presentation in patients with DM.

Surgeon, Not Institution, Case Volume Is Associated With Limb Outcomes After Lower Extremity Bypass for Critical Limb Ischemia in the Vascular Quality Initiative

Studies from large administrative databases have demonstrated associations between institutional case volume and outcomes after lower extremity bypass (LEB). Using a national, prospectively collected clinical database, the objective of this study was to determine trends in the utilization of LEB and to determine the effects of both surgeon and institutional volume on outcome after LEB for critical limb ischemia (CLI). The Vascular Quality Initiative was queried to identify all LEB between 2004 and 2014. Average annual case volume was calculated by dividing an institution's or surgeon's total LEB volume by the number of years they reported to the Vascular Quality Initiative. Institutional and surgeon volumes were analyzed as continuous variables to determine the impact of volume on major adverse cardiac events, major adverse limb events, graft patency, and amputation-free survival. Hierarchical regression models were used with cases clustered by surgeon and center. Time-dependent outcomes were evaluated with multivariable shared frailty Cox proportional hazards models. From 2004 to 2014, 20,828 LEB operations were performed at 164 institutions by 791 surgeons. Average annual institutional volume ranged from 1.0 to 157.7 LEBs per year, with a median of 25.3 (interquartile range, 14-48.5). Average annual surgeon volume ranged from 1 to 57 LEBs per year with a median of 6.25 (interquartile range, 2.5-11). The median number of bypass operations per surgeon and center did not change appreciably over time; median surgeon and institution volumes were 9 and 33.5 in 2004 and 7 and 36.5 in 2014, respectively. Institutional LEB volume was not associated with major adverse cardiac or limb events or with loss of patency. However, average annual surgeon volume independently predicted major adverse limb events and primary patency (Table). Institutional and surgeon volume did not predict major adverse cardiovascular events. In contradistinction to previous studies, there was no relationship in this study between institutional LEB volume and outcomes after LEB for CLI. However, greater average annual surgeon volume was associated with improved primary patency and decreased risk of all adverse limb events. Open LEB remains a safe and effective procedure for limb salvage. Limb-related outcomes in CLI will be optimized if surgeons maintain adequate volume of LEB.