Publications

OBJECTIVE: Centralized aortic hubs frequently exist in competitive markets, which have at times demonstrated inferior surgical outcomes. Here we evaluate the impact of local market competition specifically on complex aortic surgical outcomes.

METHODS: A retrospective review included all Vascular Quality Initiative (VQI) patients between 2013 and 2022 undergoing index complex endovascular aortic repair, thoracic endovascular aortic repair, or open aortic repair. Market competition was defined by the Herfindahl-Hirschman index (HHI), using surgeon-level market share within blinded VQI regions or metropolitan statistical areas (MSAs). A higher HHI indicates lower competition. Multivariable logistic 30-day mortality models and Cox survival models were used to examine the association between HHI and outcomes. A sensitivity analysis further adjusted for complexity among all complex and routine aortic surgical patients in the Vascular Implant Surveillance and Interventional Outcomes Network from 2017 to 2019, using generalized estimating equations with MSA-level clustering.

RESULTS: The VQI contained 10,868 complex aortic surgical patients, with 4372 additional patients in MSA-based Vascular Implant Surveillance and Interventional Outcomes Network sensitivity analysis. The median patient age was 75 years. Of these patients, 68.4% were male, with a greater number of patients in high competition regions (51.3%) and MSAs (34.6%) vs medium and low competition locales. Comorbidities and aneurysm diameter were broadly similar across HHI intervals. Lower 30-day mortality was observed in high competition regions (high, 23.7%; medium, 25.9%; low, 25.9%; P = .03). In multivariable logistic models, medium regional competition was associated with greater 30-day mortality odds vs high competition (odds ratio [OR], 1.39; 95% CI, 1.21-1.60; P < .001), with a trend toward increased mortality for low competition (OR, 1.20; 95% CI, 0.98-1.45; P = .07). MSA-based sensitivity analyses demonstrated a similar trend for medium competition MSAs (OR, 1.25; 95% CI, 0.98-1.58; P = .07), without significant relationship for low-competition MSAs. Regional interval was not associated with any long-term mortality difference.

CONCLUSIONS: More competitive regions demonstrate lower 30-day mortality after complex aortic surgery but equivalent long-term survival. Further efforts should focus on drivers of this difference to widen access to high-quality complex aortic care.

We discuss generalizability analyses under a partially nested trial design, where part of the trial is nested within a cohort of trial-eligible individuals, while the rest of the trial is not nested. This design arises, for example, when only some centers participating in a trial are able to collect data on nonrandomized individuals, or when data on nonrandomized individuals cannot be collected for the full duration of the trial. Our work is motivated by the Necrotizing Enterocolitis Surgery Trial, which compared initial laparotomy versus peritoneal drain for infants with necrotizing enterocolitis or spontaneous intestinal perforation. During the first phase of the study, data were collected from randomized individuals as well as consenting nonrandomized individuals; during the second phase of the study, however, data were only collected from randomized individuals, resulting in a partially nested trial design. We propose methods for generalizability analyses with partially nested trial designs. We describe identification conditions and propose estimators for causal estimands in the target population of all trial-eligible individuals, both randomized and nonrandomized, in the part of the data where the trial is nested while using trial information spanning both parts. We evaluate the estimators in a simulation study and provide an illustration using the Necrotizing Enterocolitis Surgery Trial study.

The optimal treatment of patients with diffuse large B-cell lymphoma (DLBCL) or Hodgkin lymphoma (HL) with preexisting cardiomyopathy is uncertain. An anonymous, electronic survey was distributed by e-mail to three US lymphoma cooperative groups, two community hospitals, and twelve academic medical systems, and distributed at one international lymphoma meeting. Fifty hematology-oncology providers caring for patients with lymphoma were included. In response to a vignette of a 67-yo with Stage III DLBCL with LVEF of 40-45%, 15 (30%) would use non-anthracycline regimens, 13 (26%) R-CHOP with liposomal doxorubicin instead of doxorubicin, 11 (22%) R-CHOP without modification and 6 (12%) R-CHOP with a continuous doxorubicin infusion. In a second vignette of a patient with HL in remission after frontline treatment with doxorubicin cumulative dose 300 mg/m2, 16 (32%) would order an echocardiogram after treatment. There was substantial variability in preferred treatment regimens with preexisting cardiomyopathy and in cardiac monitoring after anthracycline.

OBJECTIVE: Despite advances in the management of chronic limb-threatening ischemia (CLTI), a large proportion of these patients are not candidates for traditional revascularization and may be destined for major amputation. Given this medically complex and no-option patient population, deep venous arterialization (DVA) has been recently revitalized as a limb salvage technique, whereby an arteriovenous fistula in the lower leg is created to supply more oxygenated blood via the venous system to the foot. Recently, PROMISE II (Percutaneous Deep Vein Arterialization for the Treatment of Late-Stage Chronic Limb-Threatening Ischemia) demonstrated a 6-month amputation-free survival (AFS) rate of 66% after DVA. With this trial in mind, our study aimed to evaluate the real-world outcomes of this procedure.

METHODS: The study population included all patients undergoing a DVA from January 1, 2021, through December 31, 2023 among fee-for-service beneficiaries identified in the Medicare Fee-for-Service Carrier Claims file. DVA procedures were identified using Current Procedural Terminology code 0620T. Outcomes included limb salvage, freedom from major adverse limb events (defined as major amputation or ipsilateral reintervention), survival, and AFS. Cumulative incidences for outcomes that include death were estimated from traditional Kaplan-Meier methods; for non-death end points, outcomes were estimated from the cumulative incidence function, accounting for the competing risk of death.

RESULTS: Between 2021 and 2023, 134 patients underwent a DVA for CLTI. Among these, the median age was 70 years and the majority of patients were male (66%), White (63%), and had tissue loss (72%), hypertension (99%), hyperlipidemia (96%), chronic kidney disease (89%), and diabetes (83%). After a DVA for CLTI, the 6-month and 1-year AFS incidences were 42% and 33%, respectively. One-year incidences of limb salvage, freedom from major adverse limb events, and survival were 53%, 36%, and 65%, respectively.

CONCLUSIONS: Among patients with no traditional options for revascularization, our data demonstrate that DVA is a procedure that is, by its nature, performed on high-risk individuals who continue to have a high risk of limb loss and mortality. Importantly, AFS in our analysis was notably worse than that reported in PROMISE II and, as such, raises questions about the generalizability of this procedure in real world practice. Further investigation is needed regarding patient selection criteria for and the clinical usefulness of the DVA procedure.

BACKGROUND: The Best Endovascular vs Best Surgical Therapy in Patients with Critical Limb Ischemia (BEST-CLI) trial reported the superiority of surgical bypass compared with endovascular intervention for the treatment of chronic limb-threatening ischemia (CLTI) in patients deemed suitable for either; however, the generalizability of these findings to the broader CLTI population is in question. Herein, we analyzed perioperative (30-day) outcomes from the National Surgical Quality Improvement Project (NSQIP) for CLTI interventions.

METHODS: The NSQIP-Vascular targeted database was queried from 2014 to 2019, contemporaneous with BEST-CLI, for patients undergoing CLTI intervention. Surgical bypass groups included saphenous vein (OPEN-GSV) or alternative conduit (OPEN-Other) and were compared to the endovascular (intervention group) (ENDO). Inverse Probability weighting with regression adjustment assessed 30-day outcomes including perioperative death (POD), major amputation, major adverse limb events (MALE, major reintervention and/or amputation), composite MALE or POD, and major adverse cardiovascular events (MACE, myocardial infarction, or stroke). Results were provided as risk ratio (RR).

RESULTS: Of the total cohort, 6780 (34.1%) were in the OPEN-GSV group, 4201 (21.1%) in OPEN-Other, and 8887 (44.7%) in ENDO. Compared to OPEN-GSV, ENDO exhibited a higher risk for major amputation (RR, 1.38; P = .002), higher risk of MALE (RR, 1.23; P = .004), lower risk of MACE (RR, 0.48; P < .001), and similar risk for all other outcomes. Compared to OPEN-Other, ENDO exhibited a lower risk of MACE (RR, 0.49; P < .001) and POD (RR, 0.76; P = .040) and was similar for all other outcomes.

CONCLUSIONS: These data demonstrate a higher rate of early amputation and MALE among those who underwent ENDO vs OPEN-GSV. Conversely, early limb events were similar between ENDO and OPEN-Other. Both OPEN-GSV and OPEN-Other were associated with a higher risk of 30-day MACE. OPEN-Other was associated with a higher risk of MACE. These data highlight the importance of patient selection to optimize overall patient outcomes in CLTI.

Endovascular renal denervation (RDN) is a catheter-based, procedural therapy for the treatment of hypertension that was approved by the US Food and Drug Administration (FDA) in November 2023. Early studies suggest that endovascular RDN reduces blood pressure (BP) in patients with hypertension. However, BP response to RDN is highly variable, optimal patient selection remains uncertain, and the procedure's high cost remains a significant challenge. The purpose of this review is to comprehensively examine the literature regarding the mechanism by which endovascular RDN reduces BP and the safety and effectiveness of RDN, and to discuss key considerations for selecting appropriate patients for endovascular RDN. Relevant studies in the field were identified from PubMed using search terms including 'renal denervation' and 'renal denervation for hypertension.' In conclusion, clinical trials have demonstrated a statistically significant BP-lowering effect of endovascular RDN, which based on multiple trials with long-term follow-up, appears to persist over several years with low complication rates. More research is needed to understand which patients benefit most from endovascular RDN and to evaluate the long-term outcomes, including the impact of endovascular RDN on cardiovascular events.

Pulmonary embolism (PE) is a life-threatening condition characterised by occlusion of the pulmonary vasculature, with a global incidence of approximately 1 in 1,000 patients. While pharmacological therapy remains the cornerstone of PE management, selected patients may benefit from catheter-directed treatments due to their potential for rapid symptom relief and swift haemodynamic stabilisation. Catheter-directed thrombolysis and catheter-directed mechanical thrombectomy are current treatment options, though their availability is still limited. This review provides a practical outlook on catheter-directed therapies for PE, outlining optimal procedural planning, device selection, technical execution, evaluation of results, and management of complications.

Endovascular operators experience elevated rates of occupational orthopedic injuries and persistent radiation exposure with current lead shielding. Novel shielding systems eliminate the need to wear lead aprons while also mitigating occupational radiation exposure, but real-world evidence of their efficacy remains needed. This study evaluated consecutive endovascular procedures requiring fluoroscopy at U.S. and international institutions following installation of a commercially available portable shielding system consisting of interlocking radiation-attenuating acrylic and soft shielding components. Live dosimeters were placed at the left shoulder of the main and assistant operators for quantification of radiation exposure. In total, 1,712 endovascular procedures performed by 671 operators at 153 sites (19% non-U.S.). In 1,712 (99.4%), radiation exposure was recorded. A majority of procedures (83.6%) were coronary interventions including diagnostic angiography (43.8%), nonchronic total occlusion PCI (27.6%), and chronic total occlusion PCI (6.7%). Median fluoroscopy time was 7.7 mins (IQR 3.9 to 15.3 min), and median radiation exposure to the main operator and first assistant was 2 μSv and 1 μSv. This was comparable to historical measurements of under-lead radiation exposure. In conclusion, the Rampart system effectively reduced radiation exposure in real-world practice, enabling a safe lead-free procedure lab.