Long-Term Mortality Predictors Using a Machine-Learning Approach in Patients With Chronic Limb-Threatening Ischemia After Peripheral Vascular Intervention

BACKGROUND

Patients with chronic limb-threatening ischemia (CLTI) face a high long-term mortality risk. Identifying novel mortality predictors and risk profiles would enable individual health care plan design and improved survival. We aimed to leverage a random survival forest machine-learning algorithm to identify long-term all-cause mortality predictors in patients with CLTI undergoing peripheral vascular intervention.

METHODS AND RESULTS

Patients with CLTI undergoing peripheral vascular intervention from 2017 to 2018 were derived from the Medicare-linked VQI (Vascular Quality Initiative) registry. We constructed a random survival forest to rank 66 preprocedural variables according to their relative importance and mean minimal depth for 3-year all-cause mortality. A random survival forest of 2000 trees was built using a training sample (80% of the cohort). Accuracy was assessed in a testing sample (20%) using continuous ranked probability score, Harrell C-index, and out-of-bag error rate. A total of 10 114 patients were included (mean±SD age, 72.0±11.0 years; 59% men). The 3-year mortality rate was 39.1%, with a median survival of 1.4 years (interquartile range, 0.7-2.0 years). The most predictive variables were chronic kidney disease, age, congestive heart failure, dementia, arrhythmias, requiring assisted care, living at home, and body mass index. A total of 41 variables spanning all domains of the biopsychosocial model were ranked as mortality predictors. The accuracy of the model was excellent (continuous ranked probability score, 0.172; Harrell C-index, 0.70; out-of-bag error rate, 29.7%).

CONCLUSIONS

Our random survival forest accurately predicts long-term CLTI mortality, which is driven by demographic, functional, behavioral, and medical comorbidities. Broadening frameworks of risk and refining health care plans to include multidimensional risk factors could improve individualized care for CLTI.

Evaluation of short-term mortality in patients with Medicare undergoing endovascular interventions for chronic limb-threatening ischemia

INTRODUCTION

Patients with chronic limb-threatening ischemia (CLTI) have high mortality rates after revascularization. Risk stratification for short-term outcomes is challenging. We aimed to develop machine-learning models to rank predictive variables for 30-day and 90-day all-cause mortality after peripheral vascular intervention (PVI).

METHODS

Patients undergoing PVI for CLTI in the Medicare-linked Vascular Quality Initiative were included. Sixty-six preprocedural variables were included. Random survival forest (RSF) models were constructed for 30-day and 90-day all-cause mortality in the training sample and evaluated in the testing sample. Predictive variables were ranked based on the frequency that they caused branch splitting nearest the root node by importance-weighted relative importance plots. Model performance was assessed by the Brier score, continuous ranked probability score, out-of-bag error rate, and Harrell's C-index.

RESULTS

A total of 10,114 patients were included. The crude mortality rate was 4.4% at 30 days and 10.6% at 90 days. RSF models commonly identified stage 5 chronic kidney disease (CKD), dementia, congestive heart failure (CHF), age, urgent procedures, and need for assisted care as the most predictive variables. For both models, eight of the top 10 variables were either medical comorbidities or functional status variables. Models showed good discrimination (C-statistic 0.72 and 0.73) and calibration (Brier score 0.03 and 0.10).

CONCLUSION

RSF models for 30-day and 90-day all-cause mortality commonly identified CKD, dementia, CHF, need for assisted care at home, urgent procedures, and age as the most predictive variables as critical factors in CLTI. Results may help guide individualized risk-benefit treatment conversations regarding PVI.

Long-Term Patient Outcomes After Femoropopliteal Peripheral Vascular Intervention in Patients With Intermittent Claudication

BACKGROUND

In patients with intermittent claudication (IC), short-term amputation rates from clinical trial data following lower extremity femoropopliteal (FP) peripheral vascular intervention (PVI) are <1% with unknown longer-term rates.

OBJECTIVES

The aim of this study was to identify revascularization and amputation rates following PVI in the FP segment and to assess 4-year amputation and revascularization rates after FP PVI for IC.

METHODS

From 2016 to 2020, 19,324 patients undergoing FP PVI for IC were included from the PINC AI Healthcare Database and evaluated by treatment level (superficial femoral artery [SFA], popliteal artery [POP], or both). The primary outcome was index limb amputation (ILA) assessed by Kaplan-Meier estimate. The secondary outcomes were index limb major amputation and repeat revascularization. HRs were estimated using Cox proportional hazard regression.

RESULTS

The 4-year index limb amputation rate following FP PVI was 4.3% (95% CI: 4.0-4.7), with a major amputation rate of 3.2% (95% CI: 2.9-3.5). After POP PVI, ILA was significantly higher than SFA alone (7.5% vs 3.4%) or both segment PVI (5.5%). In multivariate analysis, POP PVI was associated with higher ILA rates at 4 years compared with isolated SFA PVI (HR: 2.10; 95% CI: 1.52-2.91) and index limb major amputation (HR: 1.98; 95% CI: 1.32-2.95). Repeat FP revascularization rates were 15.2%; they were highest in patients undergoing both SFA and POP PVI (18.7%; P < 0.0001) compared with SFA (13.9%) and POP (17.1%) only.

CONCLUSIONS

IC patients undergoing FP PVI had 4-year rates of index limb repeat revascularization of 16.7% and ILA rates of 4.3%. Further risk factors for amputation requires further investigation.

Comparison of Outcomes Following Transcatheter Aortic Valve Replacement Requiring Peripheral Vascular Intervention or Alternative Access

Background Peripheral vascular intervention (PVI) is occasionally required to facilitate delivery system insertion or to treat vascular complications during transfemoral transcatheter aortic valve replacement (TF-TAVR). However, the impact of PVI on outcomes is not well understood. Therefore, we aimed to compare outcomes between TF-TAVR with versus without PVI and between TF-TAVR with PVI versus non-TF-TAVR. Methods and Results We retrospectively reviewed 2386 patients who underwent TAVR with a balloon-expandable valve at a single institution from 2016 to 2020. The primary outcomes were death and major adverse cardiac/cerebrovascular event (MACCE), defined as death, myocardial infarction, or stroke. Of 2246 TF-TAVR recipients, 136 (6.1%) required PVI (89% bailout treatment). During follow-up (median 23.0 months), there were no significant differences between TF-TAVR with and without PVI in death (15.4% versus 20.7%; adjusted HR [aHR], 0.96 [95% CI, 0.58-1.58]) or MACCE (16.9% versus 23.0%; aHR, 0.84 [95% CI, 0.52-1.36]). However, compared with non-TF-TAVR (n=140), TF-TAVR with PVI carried significantly lower rates of death (15.4% versus 40.7%; aHR, 0.42 [95% CI, 0.24-0.75]) and MACCE (16.9% versus 45.0%; aHR, 0.40 [95% CI, 0.23-0.68]). Landmark analyses demonstrated lower outcome rates following TF-TAVR with PVI than non-TF-TAVR both within 60 days (death 0.7% versus 5.7%, P=0.019; MACCE 0.7% versus 9.3%; P=0.001) and thereafter (death 15.0% versus 38.9%, P=0.014; MACCE 16.5% versus 41.3%, P=0.013). Conclusions The need for PVI during TF-TAVR is not uncommon, mainly due to the bailout treatment for vascular complications. PVI is not associated with worse outcomes in TF-TAVR recipients. Even when PVI is required, TF-TAVR is associated with better short- and intermediate-term outcomes than non-TF-TAVR.

Risk of Contrast-Associated Acute Kidney Injury in Patients Undergoing Peripheral Angiography with Carbon Dioxide Compared to Iodine-Containing Contrast Agents: A Systematic Review and Meta-Analysis

The aim of this systematic review was to summarise the comparative evidence on the risk of contrast-associated acute kidney injury (CA-AKI) with CO₂ or iodinated contrast medium (ICM) for peripheral vascular interventions. We searched Ovid MEDLINE, Cochrane Library, Embase, Epistemonikos, PubMed-similar-articles, clinical trial registries, journal websites, and reference lists up to February 2022. We included studies comparing the risk of CA-AKI in patients who received CO₂ or ICM for peripheral angiography with or without endovascular intervention. Two reviewers screened the references and assessed the risk of bias of the included studies. We extracted data on study population, interventions and outcomes. For the risk of CA-AKI as our primary outcome of interest, we calculated risk ratios (RRs) with a 95% confidence interval (CI) and performed random-effects meta-analyses. We identified three RCTs and five cohort studies that fully met our eligibility criteria. Based on a random-effects meta-analysis, the risk of CA-AKI was lower with CO₂ compared to ICM (8.6% vs. 15.2%; RR, 0.59; 95% CI 0.33-1.04). Only limited results from a few studies were available on procedure and fluoroscopy time, radiation dose and CO₂-related adverse events. The evidence suggests that the use of CO₂ for peripheral vascular interventions reduces the risk of CA-AKI compared to ICM. However, due to the relevant residual risk of CA-AKI with the use of CO₂, other AKI risk factors must be considered in patients undergoing peripheral vascular interventions.

Temporal trends and outcomes of peripheral artery disease revascularization and amputation among the HIV population

OBJECTIVE

With antiretroviral therapy, people with HIV (PWH) are developing age-related diseases, including peripheral arterial disease (PAD). This study examined frequency and outcomes of peripheral vascular intervention (PVI) and primary amputation in PWH.

DESIGN

We used the National Inpatient Sample (NIS) database to examine demographics, comorbidities, and temporal trends among PVI and primary amputation admissions by HIV status from 2012 to 2018.

METHODS

Inverse probability of treatment weighting was used to calculate adjusted odds of in-hospital death and amputation. Cost of hospitalization and length of stay were compared by HIV status and revascularization approach.

RESULTS

Of the 347 824 hospitalizations for PVI/amputation, 0.6% were PWH, which was stable over time. PWH had more renal and hepatic disease, whereas uninfected individuals had more traditional PAD risk factors. 55.2% of HIV+ admissions were endovascular compared with 49.3% in HIV- admissions, and 28.9% of the HIV+ admissions were elective compared with 42.1% among HIV-. HIV status did not impact amputation following PVI. In-hospital death was similar between groups following PVI or primary amputation. PWH had lower costs of hospitalization and a trend towards shorter hospital stays.

CONCLUSION

Although PWH are developing more age-related chronic illnesses, the number of PAD-associated procedures has remained flat. Despite being younger with fewer traditional PAD risk factors, PWH had higher rates of unplanned PVI admissions and endovascular revascularization but similar in-hospital outcomes. These findings suggest PWH have different risk factors for PAD and are likely underdiagnosed and undertreated, whereas those who are treated have similar outcomes to the general population.

Cardiovascular and Limb Events Following Endovascular Revascularization Among Patients ≥65 Years Old: An American College of Cardiology PVI Registry Analysis

Background We aimed to characterize the occurrence of major adverse cardiovascular and limb events (MACE and MALE) among patients with peripheral artery disease (PAD) undergoing peripheral vascular intervention (PVI), as well as associated factors in patients with chronic limb threatening ischemia (CLTI). Methods and Results Patients undergoing PVI in the American College of Cardiology's (ACC) National Cardiovascular Data Registry's PVI Registry who could be linked to Centers for Medicare and Medicaid Services data were included. The primary outcomes were MACE, MALE, and readmission within 1 month and 1 year following index CLTI-PVI or non-CLTI-PVI. Cox proportional hazards regression was used to identify factors associated with the development of the primary outcomes among patients undergoing CLTI-PVI. There were 1758 (49.7%) patients undergoing CLTI-PVI and 1779 (50.3%) undergoing non-CLTI-PVI. By 1 year, MACE occurred in 29.5% of patients with CLTI (n=519), and MALE occurred in 34.0% of patients with CLTI (n=598). By 1 year, MACE occurred in 8.2% of patients with non-CLTI (n=146), and MALE occurred in 26.1% of patients with non-CLTI (n=465). Predictors of MACE at 1 year in CLTI-PVI included end-stage renal disease on hemodialysis, congestive heart failure, prior CABG, and severe lung disease. Predictors of MALE at 1 year in CLTI-PVI included treatment of a prior bypass graft, profunda femoral artery treatment, end-stage renal disease on hemodialysis, and treatment of a previously treated lesion. Conclusions Patients ≥65 years old undergoing PVI experience high rates of MACE and MALE. A range of modifiable and non-modifiable patient factors, procedural characteristics, and medications are associated with the occurrence of MACE and MALE following CLTI-PVI.

Intravascular ultrasound in peripheral venous and arterial interventions: A contemporary systematic review and grading of the quality of evidence

Although angiography has been the primary imaging modality used in peripheral vascular intervention, this technique has major limitations due to the evaluation of three-dimensional vessels in two dimensions. Intravascular ultrasound (IVUS) is an important adjunctive tool that can address some of these limitations. This systematic review assesses the appropriateness of IVUS as an imaging modality for guiding peripheral intervention through evidence collection and clinical appraisal of studies. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a cohort of 48 studies (29 arterial; 19 venous) detailing IVUS use in peripheral vascular intervention were extracted. Qualitative assessment of the studies evaluated pre- and postprocedure efficacy of IVUS and revealed that IVUS-guided peripheral intervention in arterial and venous diagnosis and treatment was superior to other imaging techniques alone. Each study in the cohort was further assessed for reliability and validity using the Oxford Centre for Evidence Based Medicine (CEBM) level of evidence scale. The majority of both arterial (79.3%) and venous (73.7%) studies received a 2b rating, the second highest level of evidence rating. The evidence to date indicates that IVUS results in better clinical outcomes overall and should be more widely adopted as an adjunctive imaging modality during peripheral intervention. (PROSPERO Registration No.: CRD42021232353).

Contemporary Outcomes of Limb-Salvage Procedures Using Vascular Quality Initiative-Medicare Linked Data: Racial and Ethnic Disparities Persist

INTRODUCTION

Several reports have shown that ethnic and racial minorities with chronic limb-threatening ischemia (CLTI) are more likely to undergo major amputation. Whether this disparity is driven by limited access to care, statistical discrimination or biological factors remains a matter of debate. We sought to study the effect of race/ethnicity on short and long-term outcomes of limb-salvage procedures among patients with new onset CLTI.

METHODS

We identified all patients who underwent first time (open or endovascular) revascularization for CLTI between January 2010 and December 2016 in the Vascular Quality Initiative-Medicare linked database. These patients were divided into non-Hispanic whites (NHW) and racial/ethnic minority (REM) groups. Early end points included length of stay and operative mortality, while 2-year outcomes included major amputation, freedom from subsequent revascularization, number of limb salvage reinterventions and all-cause mortality. A sub-analysis comparing NHWs to Hispanics and NHWs to blacks was also performed.

RESULTS

Of 16,249 presenting with CLTI, 73.9% were non-Hispanic whites. Racial/ethnic minority patients were younger (mean age, 69.9 ± 11.3 years vs 74.2 ± 10.5 years; P < .001) and more likely to be female (45.9% vs 37.7%; P < .001). Other baseline differences included a higher rate of smoking history, coronary artery disease, chronic obstructive pulmonary disease and chronic kidney disease among non-Hispanic whites, whereas racial/ethnic minority patients were more likely to have diabetes and hypertension and more likely to present with tissue loss (78% vs 76.6%; P =.04). Preoperative ankle-brachial index and procedure type (endovascular vs open) were similar between the groups. On multivariable analysis, NHW's had a 13% increase in length of stay and a 25% decrease in operative mortality. In regard to 2-year outcomes, limb salvage estimates were 86% for the NHW group versus 77.1% for the REM group; P < .001. Comparison between the two groups showed similar rates of freedom from subsequent revascularization (67.9% vs 67.1%; P =.2). REM patients achieved higher rates of overall survival (70.3% vs 68.4%; P =.01) when compared to their white counterparts. Patients in the REM group were more likely to undergo more than two limb salvage reinterventions during follow-up (14.2% vs 8.6%; P < .001). After adjusting for potential confounders, REM patients had significantly higher odds of major amputation at 2 years (adjusted hazard ratio, 1.49; 95% confidence interval, 1.36-1.63; P < .001) CONCLUSIONS: In this Vascular Quality Initiative-Medicare matched study, racial and ethnic minority patients continue to face a higher major amputation risk despite having equivalent attempts at limb salvage. Further studies identifying risk factors and evaluating intervention strategies that may be more effective in preventing amputation in this particular population are warranted.

Development and validation of a predictive model for bleeding after peripheral vascular intervention: A report from the National Cardiovascular Data Registry Peripheral Vascular Interventions Registry

OBJECTIVES

To develop a model to predict risk of in-hospital bleeding following endovascular peripheral vascular intervention.

BACKGROUND

Peri-procedural bleeding is a common, potentially preventable complication of catheter-based peripheral vascular procedures and is associated with increased mortality. We used the National Cardiovascular Data Registry (NCDR) Peripheral Vascular Interventions (PVI) Registry to develop a novel risk-prediction model to identify patients who may derive the greatest benefit from application of strategies to prevent bleeding.

METHODS

We examined all patients undergoing lower extremity PVI at 76 NCDR PVI hospitals from 2014 to 2017. Patients with acute limb ischemia (n = 1600) were excluded. Major bleeding was defined as overt bleeding with a hemoglobin (Hb) drop of ≥ 3 g/dl, any Hb decline of ≥ 4 g/dl, or a blood transfusion in patients with pre-procedure Hb ≥ 8 g/dl. Hierarchical multivariable logistic regression was used to develop a risk model to predict major bleeding. Model validation was performed using 1000 bootstrapped replicates of the population after sampling with replacement.

RESULTS

Among 25,382 eligible patients, 1017 (4.0%) developed major bleeding. Predictors of bleeding included age, female sex, critical limb ischemia, non-femoral access, prior heart failure, and pre-procedure hemoglobin. The model demonstrated good discrimination (optimism corrected c-statistic = 0.67), calibration (corrected slope = 0.98, intercept of -0.04) and range of predicted risk (1%-18%).

CONCLUSIONS

Post-procedural PVI bleeding risk can be predicted based upon pre- and peri-procedural patient characteristics. Further studies are needed to determine whether this model can be utilized to improve procedural safety through developing and targeting bleeding avoidance strategies.

Should Interventional Cardiologists Super-Subspecialize?: Moving From Patient Selection to Operator Selection

The field of interventional cardiology has expanded rapidly. As a result, four evolving areas have evolved - peripheral vascular interventions, structural heart interventions, adult congenital heart intervention, and chronic total occlusion. The complexity of these procedures and the number of devices available has grown rapidly. In addition, the professional and public expectations of procedural success and of minimizing case-avoidance have also grown. Specific issues include volume-outcome relationships, maintaining currency and proficiency, accessibility to specialized procedures, and the need to maintain a fundamental level of expertise in acute coronary interventions.

Access Site Complications of Peripheral Endovascular Procedures: A Large, Prospective Registry on Predictors and Consequences

PURPOSE

The purpose of this study was to investigate predictors and consequences of acute vascular access site complications (ASCs) related to peripheral endovascular diagnostic or interventional procedures. Despite improvement of puncture techniques, access site-related morbidity and mortality is still considerable.

MATERIALS AND METHODS

A total of 5263 participants who underwent 5385 endovascular procedures at a single center were consecutively included in this prospective, observational study. Primary outcomes were ASCs defined as composite of puncture site hematoma, pseudoaneurysm, arteriovenous fistula, and overt puncture site bleeding on the first day after procedure.

RESULTS

ASCs occurred in 16.6% of peripheral endovascular procedures (78.6% hematomas, 18.9% pseudoaneurysms, 1.4% arteriovenous fistulas, 1.1% overt bleedings). Independent predictors were advanced age [odds ratio (OR) per 10 years: 1.12, p=0.004], female sex (OR men, 0.77; p=0.001), lysis (OR 3.56; p<0.001), periprocedural heparin (OR 5000 IU, 1.96; p=0.001; OR >5000 IU, 3.56; p=0.02), time to access (OR per 10 seconds, 1.01; p<0.001), sheath size (OR per French, 1.59; p<0.001), brachial artery access (OR vs retrograde transfemoral, 4.58; p<0.001), and compression only (OR Angio-Seal, 0.57, p=0.02; ProGlide, 0.36, p<0.001; FemoSeal, 0.57, p<0.001). Treatment was required in 20.2% and prolonged hospitalization in 17.7% of ASC. Three participants died from access site-related bleeding.

CONCLUSION

ASCs after peripheral endovascular procedures are associated with advanced age, female sex, periprocedural antithrombotic medication, brachial artery access, postinterventional bleeding, and nonuse of vascular closure devices.

Preclinical study testing feasibility and technical requirements for successful telerobotic long distance peripheral vascular intervention

BACKGROUND

Robotic-assisted endovascular surgery enables us to perform interventions from long distances. This study evaluates the workflow and telecommunication requirements of telerobotic peripheral vascular interventions.

METHODS

Ten superficial femoral artery cases were performed by the operator being 44 miles away from the interventional suite, with an endovascular robotic system, on a high-fidelity endovascular simulator. Procedural success, technical success, fluoroscopy time, residual stenosis, contrast dose and network delay were registered. Communication success was assessed after each procedure on a scale from 1 (unacceptable) to 5 (ideal).

RESULTS

Procedural success and technical success were 100% and 80%, respectively. The mean residual stenosis, fluoroscopy time and contrast dose were 1.7 ± 5.25%, 6.5 ± 1.8 min and 58.8 ± 14.8 ml. The mean network latency was 38.9 ± 3.5 ms. Median communication success scores were 4.5 (min: 4, max: 5) reported by both the operator and the bedside technician on a scale of 1 (unacceptable) to 5 (ideal).

CONCLUSION

With a stable network connection and good communication protocol, a high success rate was achieved for remote robotic-assisted peripheral vascular intervention in an ex vivo model.

Orbital atherectomy for treating calcified iliac artery disease to enable large bore device delivery: A case series report

The current standard of care for the treatment of flow-limiting calcific iliac artery disease is balloon angioplasty and subsequent stent placement. However, the presence of calcified lesions may prevent adequate stent expansion or impede the delivery of large bore devices, such as those for transcatheter aortic valve replacement or endovascular aneurysm repair implants. Plaque modification through vessel preparation with orbital atherectomy may enable stent expansion and subsequent proper large device delivery with low rates of procedural complications. A retrospective, single center, case series of 13 subjects treated with orbital atherectomy in iliac arteries to enable large bore device delivery was conducted. Patients were selected for treatment based on iliac artery disease or inability to deliver devices. The procedural complication rate was defined as the composite of flow-limiting dissection, perforation, slow flow, vessel closure, spasm, embolism, and thrombosis. Technical success was assessed as angiographic luminal gain and subsequent successful delivery of large bore devices through the treatment area, as well as freedom from procedural complications. Orbital atherectomy vessel preparation of severely calcified iliac artery lesions resulted in adequate stent expansion safely and enabled delivery of rigid/large profile devices. Further studies are warranted to evaluate patient selection criteria, as well as long-term efficacy and safety rates of orbital atherectomy in the iliac artery.

Differences in risk factors and resource utilization for women undergoing percutaneous coronary intervention and lower extremity peripheral vascular intervention

OBJECTIVE

To investigate the differences in risk factors and in-hospital outcomes for women undergoing percutaneous coronary intervention (PCI) and peripheral vascular intervention (PVI).

BACKGROUND

The clinical impact of coronary artery disease (CAD) and peripheral artery disease (PAD) is well characterized and is associated with high morbidity and mortality. There is lack of data comparing risk factors and in-hospital outcomes for PCI and PVI, particularly in women.

METHODS

Only female hospitalizations (age ≥ 18 years) who underwent PCI or PVI from 2005 to 2014 were identified using appropriate International Classification of Diseases-Ninth Revision, Clinical Modification codes from the National Inpatient Sample database. Charlson's Comorbidity Index (CCI) was selected as the primary endpoint of the study. Coprimary endpoint was the cost of hospitalizations associated with PCI or PVI.

RESULTS

Of the 2,461,328 female hospitalizations that were included, 85.6% (N = 2,105,236) underwent PCI and 14.4% (N = 356,092) received PVI. Compared to PCI, PVI hospitalizations were 3.2 years older (p < .001) and consisted of significantly more hospitalizations above 80 years of age (26.5% vs. 18.6%; p < .001). Hospitalizations with CCI ≥3 were significantly higher in the PVI cohort (29.1% vs. 24%; p < .001). CCI in women increased during the study period for both groups. PVI hospitalizations had a significantly longer length of stay (3 days vs. 2 days; p < .001) and cost of hospitalization ($23,610 vs. $20,571; p < .001), compared to PCI. Finally, the mean cost of hospitalizations increased during the study period for PCI and PVI.

CONCLUSION

Women hospitalized for PVI had a greater risk-profile and resource utilization as demonstrated by the longer length of stay and higher cost compared to PCI.

Loss to follow-up 1 year after lower extremity peripheral vascular intervention is associated with worse survival

Loss to follow-up (LTF) has been associated with worse outcomes after procedures. We sought to identify differences in lower extremity peripheral vascular intervention (PVI) patients with and without LTF, and to determine if LTF impacted survival. Patients in the PVI registry of the Vascular Quality Initiative (VQI) were included (n = 39,342), where t-test and chi-squared analysis were used to compare those with and without LTF. Multivariable logistic regression was used to identify factors associated with LTF while Cox regression analysis was applied to compare survival among those with and without LTF. The overall 1-year follow-up rate was 91.6%. LTF patients were more often male, Hispanic, of black race, and had a higher rate of diabetes, coronary artery disease, congestive heart failure, and dialysis. LTF patients had a higher prevalence of critical limb ischemia, underwent popliteal or distal intervention, and were intervened upon urgently. There was also a higher rate of postoperative complications, and a lower rate of technical success for LTF patients. After controlling for center effects, the independent variables associated with LTF included male sex, age, diabetes, dialysis dependence, ASA class 3 or greater, as well as complications requiring admission. Preoperative aspirin, preadmission home living status, prior carotid intervention, and discharge aspirin were protective against LTF. Adjusted survival analysis showed decreased survival in LTF, with those returning face-to-face surviving longer than those with phone follow-up. Efforts should be focused on understanding these differences to improve follow-up rates and help improve overall survival.

Peripheral vascular interventional advances in 2017

Aim of this review is to inform major clinical trials in peripheral vascular interventions in the year of 2017.

The association of race with quality of health in peripheral artery disease following peripheral vascular intervention: The Q-PAD Study

Black patients have a higher prevalence of peripheral artery disease (PAD) than white patients, and also tend to have a greater extent and severity of disease, and poorer outcomes. The association of race with quality of health (QOH) after peripheral vascular intervention (PVI), however, is less well-known. In our study, we hypothesized that after PVI, black patients experience worse QOH than white patients. We retrospectively assessed racial differences in health status using responses to the Peripheral Arterial Questionnaire (PAQ) at baseline (pre-PVI) and up to 6 months following PVI among 387 patients. We used the PAQ summary score (which includes physical limitation, symptoms, social function and quality of life) as a measure of QOH. We compared QOH scores at baseline and at follow-up after PVI between black ( n=132, 34.1%) and white ( n=255, 65.9%) patients. We then computed the change in score from baseline to follow-up for each patient (the delta) and compared the median delta between the two groups. Multivariable regression was used to model the delta QOH after controlling for factors associated with race or with the delta QOH. There was no significant difference in mean QOH by race either at baseline ( p=0.09) or at follow-up ( p=0.45). There was no significant difference in the unadjusted median delta by race (white 25.3 vs black 21.5, p=0.28) and QOH scores improved significantly at follow-up in both groups, albeit the improvement was marginally lower in black compared with white patients after adjustment for baseline confounders ( b = -6.6, p=0.05, 95% CI -13.2, -0.11).

The Development of Robotic Technology in Cardiac and Vascular Interventions

Robotic technology has been used in cardiovascular medicine for over a decade, and over that period its use has been expanded to interventional cardiology and percutaneous coronary and peripheral vascular interventions. The safety and feasibility of robotically assisted interventions has been demonstrated in multiple studies ranging from simple to complex coronary lesions, and in the treatment of iliofemoral and infrapopliteal disease. These studies have shown a reduction in operator exposure to harmful ionizing radiation, and the use of robotics has the intuitive benefit of alleviating the occupational hazard of operator orthopedic injuries. In addition to the interventional operator benefits, robotically assisted intervention has the potential to also be beneficial for patients by allowing more accurate lesion length measurement, stent placement, and patient radiation exposure; however, more investigation is required to elucidate these benefits fully.

Use of Embolic Protection Devices in Peripheral Interventions

The use of embolic protection devices (EPDs) when treating coronary saphenous vein bypass grafts, performing carotid arterial stenting and treating acute coronary syndromes is well accepted. We will review currently available devices and approaches to reduce distal embolisation, first discussing their uses in carotid interventions and then in vertebral and peripheral vascular interventions.

Bivalirudin versus unfractionated heparin during peripheral vascular interventions: A Propensity-matched Study

OBJECTIVES

This study aimed to compare the association of access site complications and the use of unfractionated heparin versus bivalirudin during subinguinal peripheral vascular intervention.

BACKGROUND

Compared to unfractionated heparin, bivalirudin has been associated with fewer bleeding complications in patients undergoing percutaneous coronary intervention but more ischemic events. The safety and efficacy of direct thrombin inhibitors in peripheral vascular interventions is not well defined.

METHODS

We compared the incidence of in-hospital access site complications and discharge status among patients in the multicenter, prospective Vascular Quality Initiative registry who underwent peripheral vascular intervention between August 2007 and January 2014 using bivalirudin or unfractionated heparin. Propensity score matching was used to obtain a balanced cohort of 1,524 patients in each treatment group.

RESULTS

Patients treated with bivalirudin had a significantly lower incidence of access site hematomas (2.4% vs. 3.9%, P = 0.018), shorter post-procedural hospitalization (1.0 vs. 1.2 days, P < 0.001) and lower rates of discharge to a nursing home or rehabilitation center rather than home (7.61% vs. 9.73%, P = 0.034) when compared with unfractionated heparin-treated patients. The incidence of in-hospital access site occlusion, distal embolization, and mortality did not differ significantly between groups.

CONCLUSIONS

Patients who received bivalirudin had lower rates of access site hematoma, shorter length of stay, and improved discharge status compared with unfractionated heparin during hospitalization for peripheral vascular intervention. Randomized comparisons of these agents are needed to confirm these findings. © 2016 Wiley Periodicals, Inc.

Review of Currently Available GP IIb/IIIa Inhibitors and Their Role in Peripheral Vascular Interventions

The glycoprotein IIb/IIIa (GP IIb/IIIa) antagonists are the most recent additions to the antiplatelet agents available to the interventional radiologist. The currently available GP IIb/IIIa antagonists are abciximab, eptifibatide, and tirofiban. These medications have demonstrated excellent safety and efficacy in the setting of coronary arterial interventions. The fundamental benefit of the GP IIb/IIIa antagonists lies in their unique mechanism of action: the ability to prevent platelet aggregation, thrombus formation, and distal thromboembolism while preserving initial platelet binding to damaged vascular surfaces. A paucity of data exists regarding the role of GP IIb/IIIa inhibitors in peripheral vascular interventions. The GP IIb/IIIa antagonists would theoretically provide excellent antiplatelet therapy in patients undergoing any of a variety of endovascular interventions during which thrombosis or thromboembolism may endanger distal perfusion in patients with peripheral vascular disease. The goal of this summary is to review the indications for use, pharmacology, and evidence for efficacy of the GP IIb/IIIa antagonists in hopes of translating these data for application in the peripheral arterial circulation. Further research is necessary to determine how these agents may be safely used in combination with other anticoagulants or with stents, efficacy compared with standard regimens, success at preventing distal thromboembolism, and cost effectiveness.