Gender-specific Differences in Great Saphenous Vein Conduit. A Link to Lower Extremity Bypass Outcomes Disparities?

Contemporary National Incidence and Outcomes of Acute Limb Ischemia

INTRODUCTION

Acute Limb Ischemia (ALI) is a morbid and deadly diagnosis. However, existing epidemiologic studies describing ALI predate the introduction of the Affordable Care Act in 2010 and direct oral anticoagulants in 2011. Thus, we synergized the National Inpatient Sample (NIS) and United States (U.S.) Census to define contemporary trends in the incidence, treatment, and outcomes of ALI in the US.

METHODS

We included emergent admissions of adults with primary diagnosis of lower extremity ALI in survey-weighted NIS data (2005-2020). Mann-Kendal trend test evaluated ALI incidence (primary outcome), anticoagulation usage, insurance coverage, revascularization type, and in-hospital amputation/death. Multivariable logistic regression quantified covariate associations with in-hospital amputation/death.

RESULTS

Of 582,322,862 estimated hospitalizations in the NIS, 227,440 met inclusion criteria (mean age 68.80 years, 49.94% women, 76.66% White). ALI incidence peaked in 2006 (7.16/100,000 person-years) but has declined since 2015 to 4.16/100,000 person-years in 2020 (ptrend=.008). Endovascular revascularization, anticoagulation, and Medicaid coverage increased, while self-pay insurance decreased (ptrend<.05). Amputation rates significantly decreased from 8.04% to 6.54% (ptrend=.01) while death rate remained at 5.59% (ptrend=.16) over the study period. Pre-hospitalization anticoagulation was associated with decreased amputation (aOR=0.74 [95%CI 0.65-0.84]) and death (aOR=0.50 [95%CI 0.43-0.57]). When controlling for covariates, women had a higher risk of death (aOR=1.17 [95%CI 1.07-1.27], p<.0001), while Black patients had a higher risk of amputation (aOR=1.24 [95%CI 1.10-1.41], p<.0001).

CONCLUSIONS

Our U.S. population based epidemiological study demonstrates that ALI incidence and in-hospital amputation rates are decreasing, while mortality remains unchanged. We further highlight the ongoing need for ALI investigation specifically as it relates to access to care, antithrombotic therapy use, treatment strategy, and strategies to combat gender and racial disparities.

Long-Term Outcomes of Vein Adjuncts in Distal Infrainguinal Bypass

INTRODUCTION

Autologous vein is recommended for infrainguinal bypass due to improved freedom from occlusion compared to prosthetic graft. In patients without adequate vein, vein adjunct at the distal anastomosis has been suggested to improve patency in small studies. This study aimed to determine if performance of a distal vein adjunct was associated with improved freedom from occlusion in below knee popliteal and tibial bypasses compared to prosthetic bypass alone.

METHODS

A retrospective review of the Vascular Quality Initiative Infrainguinal Bypass database was conducted. Patients undergoing prosthetic-only and prosthetic with vein adjunct were compared. Inclusion criteria included age >18 years, and bypass to below knee popliteal or tibial vessels. Exclusion criteria included autologous vein conduits and prior interventions. Groups were further divided into below knee popliteal and tibial subgroups.

RESULTS

A cohort of 3,939 patients underwent bypass to the below knee popliteal artery, with 287 (7.3%) receiving vein adjunct. More patients were male (68.8 vs 57.8%, p<.001) and had higher rates of CHF (21.1 vs 16.0%, p=.040) within the below knee popliteal group. Two-year bypass occlusion was decreased in patients receiving vein adjuncts (11.6 vs 17.1%, p=.004). A cohort of 2,378 patients underwent tibial bypass, with 473 (19.9%) receiving vein adjunct. Within the tibial group, patients were similar in age, BMI, race, comorbidities, and indications. Bypass occlusion (24.8 vs. 17.6%, p=.005) and amputation (20.5 vs. 15.9%, p=.048) rates at two years were worse for patients who did not receive a distal vein adjuncts to tibial arteries.

CONCLUSION

Distal vein adjuncts are associated with improved freedom from occlusion, amputation, MALEs, and overall survival when compared to bypasses performed with prosthetic graft alone for tibial bypasses within the VQI. Vein adjunct was not associated with improved freedom from occlusion in below knee popliteal bypasses. Consideration should be given to utilization of a distal vein adjunct to improve prosthetic bypass longevity and limb salvage for patients requiring tibial bypasses.

Coronary artery bypass surgery versus percutaneous interventions for women with multivessel coronary artery disease

OBJECTIVE

To compare outcomes in women undergoing percutaneous coronary intervention (PCI) and coronary artery bypass graft (CABG) surgery.

DESIGN

This retrospective, propensity-score matched cohort study from the New York State cardiac registry (2012-2018) included all women with multivessel coronary artery disease undergoing PCI with everolimus-eluting stents (EES) and CABG surgery. The primary outcome was all-cause mortality. The key secondary outcome was major adverse cardiac events, defined as the composite of all-cause mortality, myocardial infarction, and stroke.

RESULTS

PCI with EES was associated with a higher 6-year risk of mortality (25.75% vs 23.57%; adjusted hazard ratio [AHR], 1.29; 95% confidence interval [CI], 1.14-1.45). PCI also was associated with a higher rate of the composite outcome of death, myocardial infarction, and stroke (36.58% vs 32.89%; AHR, 1.28; 95% CI, 1.17-1.41), as well as myocardial infarction (14.94% vs 9.12%; AHR, 1.84; 95% CI, 1.56-2.17), but not stroke (7.07% vs 7.62%; AHR, 0.83; 95% CI, 0.67-1.03). Repeat revascularization rates also were higher for women undergoing PCI (21.53% vs 11.57%; AHR, 1.88; 95% CI, 1.63-2.17). There was no difference in mortality between the 2 interventions when PCI patients received complete revascularization or had noncomplex lesions and for women without diabetes.

CONCLUSIONS

For women with multivessel coronary artery disease, CABG surgery is associated with lower 6-year mortality, myocardial infarction, and repeat revascularization rates compared to PCI with EES.

Integrative multiomics analysis of neointima proliferation in human saphenous vein: implications for bypass graft disease

Introduction

Human saphenous veins (SV) are widely used as grafts in coronary artery bypass (CABG) surgery but often fail due to neointima proliferation (NP). NP involves complex interplay between vascular smooth muscle cells (VSMC) and fibroblasts. Little is known, however, regarding the transcriptomic and proteomic dynamics of NP. Here, we performed multi-omics analysis in an ex vivo tissue culture model of NP in human SV procured for CABG surgery.

Methods and results

Histological examination demonstrated significant elastin degradation and NP (indicated by increased neointima area and neointima/media ratio) in SV subjected to tissue culture. Analysis of data from 73 patients suggest that the process of SV adaptation and NP may differ according to sex and body mass index. RNA sequencing confirmed upregulation of pro-inflammatory and proliferation-related genes during NP and identified novel processes, including increased cellular stress and DNA damage responses, which may reflect tissue trauma associated with SV harvesting. Proteomic analysis identified upregulated extracellular matrix-related and coagulation/thrombosis proteins and downregulated metabolic proteins. Spatial transcriptomics detected transdifferentiating VSMC in the intima on the day of harvesting and highlighted dynamic alterations in fibroblast and VSMC phenotype and behavior during NP. Specifically, we identified new cell subpopulations contributing to NP, including SPP1 + , LGALS3 + VSMC and MMP2 + , MMP14 + fibroblasts.

Conclusion

Dynamic alterations of gene and protein expression occur during NP in human SV. Identification of the human-specific molecular and cellular mechanisms may provide novel insight into SV bypass graft disease.

Sex-Related Disparities in Acute Limb Ischemia Treatment Outcomes

BACKGROUND

Although a substantial impetus behind disparities research in healthcare exists, those that are sex-related within vascular surgery outcomes are largely unexplored. Consequently, published guidelines lack specificity when it comes to treating male and female patients with vascular disease. Disparities related to patients suffering from chronic limb-threatening ischemia have been broached, although no extensive studies assessing disparities in acute limb ischemia treatment outcomes have come to the forefront. In this study, our aim is to identify and quantify sex-related disparities as they pertain to interventions for acute limb ischemia.

METHODS

Using the TriNetX global research network, we conducted a multicenter query across 48 healthcare organizations spanning 5 countries for patients treated for acute limb ischemia. We determined the number of male and female patients that received one of the following interventions: open revascularization, percutaneous mechanical thrombectomy, or catheter-directed thrombolysis and/or adjunctive endovascular procedures. Propensity score matching was performed to account for comorbidities. Risk of adverse outcomes within 30 days was calculated for each sex, including reintervention, major amputation, and death. Risk of adverse outcomes was then compared between treatment groups of the same sex and between sexes. Type-I errors were reduced through utilization of the Holm-Bonferroni method to correct P values.

RESULTS

Within our study, we noted several important findings. Females were more likely to receive catheter-directed thrombolysis and/or adjunctive endovascular procedures (P = 0.001) than males. There were no significant differences in the rates of open revascularization or percutaneous mechanical thrombectomy between males and females. Overall, females were more likely to die within 30 days (P < 0.0001) and greater number of males required reintervention within 30 days (P < 0.0001). Analyzing outcomes within individual treatment groups, females undergoing open revascularization or catheter-directed thrombolysis and/or adjunctive endovascular intervention demonstrated a profound increase in mortality within 30 days of intervention (P = 0.0072 and P = 0.0206, respectively), but these differences were not reflected in the percutaneous mechanical thrombectomy group. Limb salvage rates in females were higher than males overall although there were no significant sex differences within any treatment groups specifically.

CONCLUSIONS

In conclusion, there was a significantly higher risk of death in females across all treatment groups in the studied timeframe. Limb salvage rates were higher for females in the open revascularization (OR) treatment group, while males were more likely to require a reintervention across all treatment groups. By evaluating these disparities, we can provide greater insight into personalized treatment for patients presenting with acute limb ischemia.

Correlations between ultrasound, tomographic, and intraoperative measurements of the great saphenous vein used as an arterial graft

Background

The great saphenous vein is the major superficial vein of the lower limb, and also the most often used as arterial graft material for lower limb revascularization. Prior knowledge of the quality of the vein can guide choice of therapeutic strategy, avoiding surgery that is doomed to failure. Discrepancies between intraoperative findings of the quality of the great saphenous vein and imaging tests are also frequently observed.

Objectives

To evaluate the diameter of the great saphenous vein using two imaging methods (Duplex Ultrasound and Computed Tomography) and the gold-standard (intraoperative direct measurement of the vein), comparing the results.

Methods

Prospective, observational study of data obtained during routine medical procedures performed by the Vascular Surgery team.

Results

41 patients were evaluated, with a 12-month follow-up. 27 (65.85%) were male and mean age was 65.37 years. 19 (46.34%) patients had femoropopliteal grafts and 22 (53.66%) had distal grafts. Preoperative saphenous vein internal diameters measured with the patient supine were on average 16.4% smaller on CT and 33.8% smaller on US than the external diameters measured after intraoperative hydrostatic dilatation. There were no statistical differences in measurements when sex, weight, and height were considered.

Conclusions

Saphenous vein diameters were underestimated by preoperative US and CT scans when compared to intraoperative measurements. Thus, in patients undergoing graft planning for revascularization, the choice of conduit should take this data into consideration, so that use of the saphenous vein is not ruled out unnecessarily during planning.

Sex Differences in Trends and In-Hospital Outcomes Among Patients With Critical Limb Ischemia: A Nationwide Analysis

Background Critical limb ischemia (CLI) represents the most severe form of peripheral artery disease and is associated with significant mortality and morbidity. Contemporary data comparing the sex differences in trends, revascularization strategies, and in-hospital outcomes among patients with CLI are scarce. Methods and Results Using the National Inpatient Sample database years 2002 to 2015, we identified hospitalizations for CLI. Temporal trends for hospitalizations for CLI were evaluated. The differences in demographics, revascularization, and in-hospital outcomes between both sexes were compared. Among 2 400 778 CLI hospitalizations, 43.6% were women. Women were older and had a higher prevalence of obesity, hypertension, heart failure, and prior stroke. Women were also less likely to receive any revascularization (34.7% versus 35.4%, P<0.001), but the trends of revascularization have been increasing among both sexes. Revascularization was associated with lower in-hospital mortality among women (adjusted odds ratio [OR], 0.76; 95% CI, 0.71-0.81) and men (adjusted OR, 0.69; 95% CI, 0.65-0.73). On multivariable analysis adjusting for patient- and hospital-related characteristics as well as revascularization, women had a higher incidence of in-hospital mortality, postoperative hemorrhage, need for blood transfusion, postoperative infection, ischemic stroke, and discharge to facilities compared with men. Conclusions In this nationwide contemporary analysis of CLI hospitalizations, women were older and less likely to undergo revascularization. Women had a higher incidence of in-hospital mortality and bleeding complications compared with men. Sex-specific studies and interventions are needed to minimize these gaps among this high-risk population.

Arterial diameter and the gender disparity in stroke thrombectomy outcomes

BACKGROUND

Compared with males, females consistently fare worse following mechanical thrombectomy for large vessel ischemic strokes. Understanding why this gender disparity occurs may guide improvements in future treatment strategies. In this study, we aim to determine whether gender differences in cerebral arterial diameter correlate with clinical outcomes following stroke thrombectomy.

METHODS

We performed an observational study of consecutive acute ischemic stroke patients undergoing mechanical thrombectomy at a single, urban tertiary care medical center. Catheter angiographic images were used to manually measure proximal segment arterial diameters in a standardized fashion. Medical record review was used to obtain relevant independent and dependent variables.

RESULTS

Ninety two patients (42 females) between June 2013 and August 2016 met inclusion criteria. Internal carotid artery (ICA) terminus diameters for males and females were 3.08 mm (SD=0.46) and 2.81 mm (SD=0.45), respectively (P=0.01). M1 segment middle cerebral artery (MCA) diameters for males and females were 2.47 mm (SD=0.30) and 2.18 mm (SD=0.31), respectively (P<0.0001). 48% of patients in the upper MCA caliber tertile attained a favorable mRS 90 day value compared with 35% in each of the lower and middle tertiles (P=0.51). Larger MCA diameters correlated with favorable discharge disposition (P=0.21).

CONCLUSIONS

These results provide limited evidence that males have larger cerebral arterial diameters than females and that larger arterial diameters may improve the odds for favorable clinical outcomes. If future studies validate these findings, arterial diameter may become a relevant variable in the design of improved thrombectomy strategies.