Intravascular Ultrasound Use in Peripheral Arterial and Deep Venous Interventions: Multidisciplinary Expert Opinion From SCAI/AVF/AVLS/SIR/SVM/SVS

Percutaneous revascularization is the primary strategy for treating lower extremity venous and arterial disease. Angiography is limited by its ability to accurately size vessels, precisely determine the degree of stenosis and length of lesions, characterize lesion morphology, or correctly diagnose postintervention complications. These limitations are overcome with use of intravascular ultrasound (IVUS). IVUS has demonstrated the ability to improve outcomes following percutaneous coronary intervention, and there is increasing evidence to support its benefits in the setting of peripheral vascular intervention. At this stage in its evolution, there remains a need to standardize the use and approach to peripheral vascular IVUS imaging. This manuscript represents considerations and consensus perspectives that emerged from a roundtable discussion including 15 physicians with expertise in interventional cardiology, interventional radiology, and vascular surgery, representing 6 cardiovascular specialty societies, held on February 3, 2023. The roundtable's aims were to assess the current state of lower extremity revascularization, identify knowledge gaps and need for evidence, and determine how IVUS can improve care and outcomes for patients with peripheral arterial and deep venous pathology.

Radioembolization plus Immune Checkpoint Inhibitor Therapy Compared with Radioembolization plus Tyrosine Kinase Inhibitor Therapy for the Treatment of Hepatocellular Carcinoma

PURPOSE

To investigate if combination therapy with immune checkpoint inhibitor (ICI) and yttrium-90 (90Y) radioembolization results in superior outcomes than those yielded by tyrosine kinase inhibitor (TKI) therapy and 90Y for the treatment of intermediate- to advanced-stage hepatocellular carcinoma (HCC).

METHODS

A retrospective review of patients presented at an institutional multidisciplinary liver tumor board between January 1, 2012 and August 1, 2023 was conducted. In total, 44 patients with HCC who underwent 90Y 4 weeks within initiation of ICI or TKI therapy were included. Propensity score matching was conducted to account for baseline demographic differences. Kaplan-Meier analysis was used to compare median progression-free survival (PFS) and overall survival (OS), and univariate statistics identified disease response and control rate differences. Duration of imaging response was defined as number of months between the first scan after therapy and the first scan showing progression as defined by modified Response Evaluation Criteria in Solid Tumors (mRECIST) or immune Response Evaluation Criteria in Solid Tumors (iRECIST). Adverse events were analyzed per Common Terminology Criteria for Adverse Events (CTCAE) version 5.0.

RESULTS

Patients in the 90Y+ICI therapy group had better objective response rates (ORRs) (89.5% vs 36.8%; P < .001) and disease control rates (DCRs) (94.7% vs 63.2%; P < .001) by mRECIST and iRECIST (ORR: 78.9% vs 36.8%; P < .001; DCR: 94.7% vs 63.2%; P < .001). Median PFS (8.3 vs 4.1 months; P = .37) and OS (15.8 vs 14.3 months; P = .52) were not statistically different. Twelve patients (63.1%) in the 90Y+TKI group did not complete systemic therapy owing to adverse effects compared with 1 patient (5.3%) in the 90Y+ICI group (P < .001). Grade 3/4 adverse events were not statistically different (90Y+TKI: 21.1%; 90Y+ICI: 5.3%; P = .150).

CONCLUSIONS

Patients with HCC who received 90Y+ICI had better imaging response and fewer regimen-altering adverse events than those who received 90Y+TKI. No significant combination therapy adverse events were attributable to radioembolization.

Developmental or Procedural Vena Cava Interruption and Venous Thromboembolism: A Review

The inferior vena cava (IVC) and superior vena cava are the main conduits of the systemic venous circulation into the right atrium. Developmental or procedural interruptions of vena cava might predispose to stasis and deep vein thrombosis (DVT) distal to the anomaly and may impact the subsequent rate of pulmonary embolism (PE). This study aimed to review the various etiologies of developmental or procedural vena cava interruption and their impact on venous thromboembolism. A systematic search was performed in PubMed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines per each clinical question. For management questions with no high-quality evidence and no mutual agreements between authors, Delphi methods were used. IVC agenesis is the most common form of congenital vena cava interruption, is associated with an increased risk of DVT, and should be suspected in young patients with unexpected extensive bilateral DVT. Surgical techniques for vena cava interruption (ligation, clipping, and plication) to prevent PE have been largely abandoned due to short-term procedural risks and long-term complications, although survivors of prior procedures are occasionally encountered. Vena cava filters are now the most commonly used method of procedural interruption, frequently placed in the infrarenal IVC. The most agreed-upon indication for vena cava filters is for patients with acute venous thromboembolism and coexisting contraindications to anticoagulation. Familiarity with different forms of vena cava interruption and their local and systemic adverse effects is important to minimize complications and thrombotic events.

Contemporary Management and Outcomes of Patients With High-Risk Pulmonary Embolism

BACKGROUND

Contemporary care patterns/outcomes in high-risk pulmonary embolism (PE) patients are unknown.

OBJECTIVES

This study sought to characterize the management of high-risk PE patients and identify factors associated with poor outcomes.

METHODS

A retrospective analysis of the PERT (Pulmonary Embolism Response Team) Consortium Registry was performed. Patients presenting with intermediate-risk PE, high-risk PE, and catastrophic PE (those with hemodynamic collapse) were identified. Patient characteristics were compared with chi-square testing for categorical covariates and Student's t-test for continuous covariates. Multivariable logistic regression was used to assess associations between clinical characteristics and outcomes in the high-risk population.

RESULTS

Of 5,790 registry patients, 2,976 presented with intermediate-risk PE and 1,442 with high-risk PE. High-risk PE patients were more frequently treated with advanced therapies than intermediate-risk PE patients (41.9% vs 30.2%; P < 0.001). In-hospital mortality (20.6% vs 3.7%; P < 0.001) and major bleeding (10.5% vs. 3.5%; P < 0.001) were more common in high-risk PE. Multivariable regression analysis demonstrated vasopressor use (OR: 4.56; 95% CI: 3.27-6.38; P < 0.01), extracorporeal membrane oxygenation use (OR: 2.86; 95% CI: 1.12-7.30; P = 0.03), identified clot-in-transit (OR: 2.26; 95% CI: 1.13-4.52; P = 0.02), and malignancy (OR: = 1.70; 95% CI: 1.13-2.56; P = 0.01) as factors associated with in-hospital mortality. Catastrophic PE patients (n = 197 [13.7% of high-risk PE patients]) had higher in-hospital mortality (42.1% vs 17.2%; P < 0.001) than those presenting with noncatastrophic high-risk PE. Extracorporeal membrane oxygenation (13.3% vs. 4.8% P < 0.001) and systemic thrombolysis (25% vs 11.3%; P < 0.001) were used more commonly in catastrophic PE.

CONCLUSIONS

In the largest analysis of high-risk PE patients to date, mortality rates were high with the worst outcomes among patients with hemodynamic collapse.

IN.PACT AV Access Randomized Trial of Drug-Coated Balloons for Dysfunctional Arteriovenous Fistulae: Clinical Outcomes through 36 Months

PURPOSE

To present the 36-month outcomes of the prospective randomized IN.PACT AV Access study of participants with obstructive de novo or restenotic native upper extremity arteriovenous dialysis fistula lesions treated with drug-coated balloon (DCBs) or standard percutaneous transluminal angioplasty (PTA) following successful high-pressure PTA.

MATERIALS AND METHODS

Participants at 29 international sites were randomized 1:1 to receive an IN.PACT AV DCB (n = 170) or undergo PTA (n = 160). The outcomes through 36 months included target lesion primary patency (TLPP) and access circuit primary patency (ACPP) (composites of clinically driven target lesion or access circuit revascularization and/or access circuit thrombosis), number of reinterventions, and serious adverse events involving the access circuit.

RESULTS

TLPP was 52.1% in the DCB group compared with 36.7% in the PTA group through 24 months and 43.1% in the DCB group compared with 28.6% in the PTA group through 36 months (both log-rank P < .001). ACPP was 39.4% in the DCB group compared with 25.3% in the PTA group through 24 months and 26.4% in the DCB group compared with 16.6% in the PTA group through 36 months (both log-rank P < .001). Cumulative incidence of access circuit thrombosis through 36 months was 8.2% in the DCB group compared with 18.3% in the PTA group (log-rank P = .040). Cumulative incidence of mortality through 36 months was 26.6% in the DCB group compared with 30.8% in the PTA group (log-rank P = .71).

CONCLUSIONS

This study demonstrated superior TLPP and ACPP with DCBs compared with PTA, with no difference in mortality through 3 years. Access circuit thrombosis was statistically significantly higher in the PTA group at 3 years.

Women are Not at Higher Risk for Reintervention or Major Amputation after Lower Extremity Atherectomy for Peripheral Artery Disease

BACKGROUND

Our objective was to compare short-term and long-term differences in reintervention-free and major amputation-free survival between female and male patients undergoing lower extremity atherectomy for peripheral artery disease.

METHODS

We analyzed lower extremity atherectomy procedures performed on 294 patients between January 2014 and September 2019. Reintervention was defined as either open bypass or endovascular procedure to the same region following the index operation. Kaplan-Meier (KM) survival analysis was performed to compare reintervention-free and major amputation-free survival between sexes. Multivariate logistic regression analyses were performed to determine the adjusted odds of reintervention and major amputation based on sex. We conducted subgroup analyses by anatomic region (femoropopliteal vs. tibial), indication (claudication vs. chronic limb-threatening ischemia (CLTI)), and balloon type (drug-coated balloon (DCB) versus plain balloon angioplasty (POBA)) across sexes.

RESULTS

Of the 294 patients, 125 (42.5%) were female. Compared to men, women receiving atherectomy were more likely to be Black (28.0% vs. 16.6%; P = 0.018), a nonsmoker (44.8% vs. 21.3%; P < 0.001), and present with CLTI (55.2% vs. 43.2%; P = 0.042). There were no differences in atherectomy region, lesion type, or balloon type between sexes. KM analysis showed similar 4-year reintervention-free survival (68.8% vs. 75.1%; P = 0.88) and major amputation-free survival (97.6% vs. 97.6%; P = 0.41) between sexes. Women and men had similar reintervention-free survival when grouped by femoropopliteal (67.9% vs. 70.8%; P = 0.69) or tibial (76.2% vs. 83.9%; P = 0.68) atherectomy region. Indication (claudication versus CLTI) did not affect reintervention-free survival in either women (64.5% vs. 69.6%; P = 0.28) or men (68.5% vs. 76.7%; P = 0.84). KM curves for DCB versus POBA were also similar between sexes and showed an early benefit in reintervention rate favoring DCB, which dissipated in both women (65.4% vs. 72.7%; P = 0.61) and men (75.5% vs. 78.4%; P = 0.18) by 3 years.

CONCLUSIONS

Compared to men, women demonstrate commensurate benefit from atherectomy for lower extremity revascularization. There were no differences seen in long-term reintervention or major amputation between sexes.

Predictors of pulmonary embolism in hospitalized patients with COVID-19

BACKGROUND

High venous thromboembolism (VTE) rates have been described in critically ill patients with COVID-19. We hypothesized that specific clinical characteristics may help differentiate hypoxic COVID-19 patients with and without a diagnosed pulmonary embolism (PE).

METHODS

We performed a retrospective observational case-control study of 158 consecutive patients hospitalized in one of four Mount Sinai Hospitals with COVID-19 between March 1 and May 8, 2020, who received a Chest CT Pulmonary Angiogram (CTA) to diagnose a PE. We analyzed demographic, clinical, laboratory, radiological, treatment characteristics, and outcomes in COVID-19 patients with and without PE.

RESULTS

92 patients were negative (CTA-), and 66 patients were positive for PE (CTA+). CTA + had a longer time from symptom onset to admission (7 days vs. 4 days, p = 0.05), higher admission biomarkers, notably D-dimer (6.87 vs. 1.59, p < 0.0001), troponin (0.015 vs. 0.01, p = 0.01), and peak D-dimer (9.26 vs. 3.8, p = 0.0008). Predictors of PE included time from symptom onset to admission (OR = 1.11, 95% CI 1.03-1.20, p = 0.008), and PESI score at the time of CTA (OR = 1.02, 95% CI 1.01-1.04, p = 0.008). Predictors of mortality included age (HR 1.13, 95% CI 1.04-1.22, p = 0.006), chronic anticoagulation (13.81, 95% CI 1.24-154, p = 0.03), and admission ferritin (1.001, 95% CI 1-1.001, p = 0.01).

CONCLUSIONS

In 158 hospitalized COVID-19 patients with respiratory failure evaluated for suspected PE, 40.8% patients had a positive CTA. We identified clinical predictors of PE and mortality from PE, which may help with early identification and reduction of PE-related mortality in patients with COVID-19.

Contextualizing the BEST-CLI Trial Results in Clinical Practice

Background

Chronic limb-threatening ischemia (CLTI) is associated with poor long-term outcomes. Although prompt revascularization is recommended, the optimal revascularization strategy remains uncertain. The BEST-CLI trial compared endovascular and open surgical revascularization for CLTI, but the generalizability of this study to the clinical population with CLTI has not been evaluated.

Methods

We included Medicare beneficiaries aged 65-85 years with CLTI who underwent revascularization and would be eligible for enrollment in BEST-CLI between 2016 and 2019. The primary exposure was type of revascularization (endovascular vs autologous graft [cohort 1] vs nonautologous graft [cohort 2]), and the primary outcome was a composite of major adverse limb events (MALE) and death. MALE included above-ankle amputation and major intervention, which was defined as new bypass of index limb, thrombectomy, or thrombolysis.

Results

A total of 66,153 patients were included in this study (10,125 autologous grafts; 7867 nonautologous grafts; 48,161 endovascular). Compared with those enrolled in BEST-CLI cohort 1, patients in this study were older (mean age, 73.5 ± 5.7 vs 69.9 ± 9.9 years), more likely to be female (38.3% [22,340/58,286] vs 28.5% [408/1434]), and presented with more comorbidities. Endovascular operators for the study population vs BEST-CLI cohort 1 were less likely to be surgeons (55.9% [26,924/48,148] vs 73.0% [520/708]) and more likely to be cardiologists (25.5% [5900/48,148] vs 14.5% [103/78]). When assessing long-term outcomes, the crude risk of death or MALE in this cohort was higher with surgery (56.6% autologous grafts vs 42.6% BEST-CLI cohort 1 at a median of follow-up 2.7 years; 51.6% nonautologous grafts vs 42.8% BEST-CLI cohort 2 at a median follow-up of 1.6 years) but similar with the endovascular cohort (58.7% Medicare vs 57.4% cohort 1 at 2.7 years; 47.0% Medicare vs 47.7% cohort 2 at 1.6 years). Of those who received endovascular treatment, the risk of incident major intervention was less than half in this cohort compared with the trial cohort (10.0% Medicare vs 23.5% cohort 1 at 2.7 years; 8.6% Medicare vs 25.6% cohort 2 at 1.6 years), although technical endovascular failures were not captured.

Conclusions

These results suggest that the findings of the BEST-CLI trial may not be applicable to the entirety of the Medicare population of patients with CLTI undergoing revascularization.

Below-the-Knee Stents and Scaffolds: A Comprehensive Review

Below-the-knee intervention of chronic limb-threatening ischemia is an area of increasing interest. Due to lower morbidity and possibly better clinical outcomes, endovascular techniques have become increasingly important in this patient population many of who have limited surgical options. This article serves as a review of existing stent and scaffolding devices utilized for infrapopliteal disease. The authors will additionally discuss current indications and review studies that are investigating novel materials used in treating infrapopliteal arterial disease.

Outcomes of Elective Compared to Non-Elective Fetal Reduction by Radiofrequency Ablation in Monochorionic Multifetal Pregnancies

INTRODUCTION

Higher order fetal gestation is associated with adverse pregnancy outcomes, and monochorionic (MC) pregnancies have unique complications. Multifetal pregnancy reduction (MPR) by radiofrequency ablation (RFA) may be used to optimize the outcomes of a single fetus. The purpose of this study was to determine whether pregnancy outcomes differ for elective reduction compared to reduction for medically complicated MC multifetal pregnancies.

METHODS

This was a retrospective cohort of patients with MC twins and higher order multiples who underwent MPR via RFA at a single institution between 2008 and 2021. Patients undergoing elective reduction were compared to patients undergoing reduction due to a complication of MC pregnancy. Pregnancy outcomes were evaluated.

RESULTS

Forty-eight patients who underwent RFA reduction between 2008 and 2021 were included in the analysis. Sixteen patients (33.3%) underwent elective RFA for MPR, and 32 (66.7%) underwent an RFA procedure for a complicated pregnancy. All pregnancies with RFA performed for elective indication had a continuing pregnancy (live birth rate 100%). There were no reported pregnancy losses within 4 weeks of the procedure when performed for a solely elective indication (n = 0) compared to 6.3% of complicated multifetal pregnancy (n = 2; 6.3%) (p = 0.001).

CONCLUSION

In this retrospective cohort study, elective reduction of MC twins using RFA was associated with no cases of fetal loss or PPROM within 4 weeks of the procedure and a 100% live birth rate.

Fertility after Transcatheter Arterial Embolization for Obstetric Hemorrhage: An Urban Health Care System Observational Study

OBJECTIVE

 This study aimed to investigate pregnancy rate, pregnancy outcomes, and resumption of menses after transcatheter arterial embolization (TAE) for obstetric hemorrhage (OH).

STUDY DESIGN

 Sixty-seven patients who underwent TAE for OH from 2006 to 2020 within an urban, multihospital health care system were identified retrospectively. Selected patients were interviewed by phone to complete a survey with a primary outcome of self-reported pregnancy in those seeking pregnancy. Secondary outcomes included pregnancy outcomes and resumption of menses. Univariate testing of association of pregnancy and miscarriage rate with embolic agent was performed using Fisher's exact test.

RESULTS

 Thirty-three of 50 patients (66%) meeting the inclusion criteria completed the survey on fertility, a median of 47 (range, 13-123) months after TAE for OH. Of the 13 patients who attempted pregnancy, there was a pregnancy rate of 77% and miscarriage rate of 38%. Those who delivered live newborns conceived spontaneously, carried to term, and delivered a healthy newborn via cesarean section at a weight appropriate for gestational age. Thirty (91%) patients resumed menstruation, and the majority with unchanged frequency. Most patients underwent bilateral uterine artery embolization with radial artery access (54%). The most common embolic agents used were gelfoam only (30%) and glue only (24%). There was no statistically significant association between embolic agent and pregnancy or miscarriage rate.

CONCLUSION

 Spontaneous pregnancy with live birth and resumption of menses can occur in a majority of patients after TAE for OH.

KEY POINTS

· Most patients who attempted pregnancy after TAE for OH achieved pregnancy.. · Most patients who became pregnant conceived spontaneously and delivered healthy newborns at term.. · Most patients resumed menstruation after TAE for OH.. · There was no significant association between type of embolic and pregnancy or miscarriage rate..

Catheter-Directed Thrombolysis for Acute Digit Ischemia in the Setting of Heterozygous Factor V Leiden Mutation: A Case Report and Review of Literature

CASE

We are reporting the successful treatment of a patient with a heterozygous factor V Leiden mutation who presented with spontaneous thrombotic ischemia of ring and small fingers. Microcatheter-directed administration of thrombolytics at the level of common and proper digital arteries resulted in the salvage of the ring finger to the level of the distal tuft and the entirety of the small finger.

CONCLUSION

Heterozygous factor V Leiden mutation is an extremely unusual etiology for thrombotic digital ischemia. This case report emphasizes the importance of correct diagnosis, timely intervention, and thrombolytic therapy using microcatheters to optimize digital rescue.

Radiation segmentectomy for curative intent of unresectable very early to early stage hepatocellular carcinoma (RASER): a single-centre, single-arm study

BACKGROUND

Unresectable solitary very early to early stage hepatocellular carcinoma is managed with ablation for curative intent. Radiation segmentectomy is a treatment option that delivers radioactive ⁹⁰yttrium (⁹⁰Y)-bound microspheres transarterially to a segment of liver. The aim of this study was to assess the safety and efficacy of radiation segmentectomy in patients with unresectable hepatocellular carcinoma deemed unfavourable for ablation.

METHODS

RASER was a single-centre, single-arm study that included adults (>18 years) with solitary hepatocellular carcinoma with unfavourable location for ablation, without metastasis or macrovascular invasion. Eligibility criteria included measurable disease 3 cm or less in diameter, Child-Pugh score A-B7, an Eastern Cooperative Oncology Group score of 0, and adequate haematological and organ function. The primary endpoint was target tumour response measured by mRECIST. Patients were followed up with imaging and office visits for up to 24 months. The trial is registered with ClinicalTrials.gov (NCT03248375), and is completed.

FINDINGS

Individuals were enrolled between Aug 3, 2016, and April 4, 2019, and the last patient follow-up occurred on March 31, 2021. Of the 44 individuals assessed for eligibility, 29 patients were included in the study. Initial target lesion complete response was observed in 24 (83%) of 29 patients, and partial response was observed in five (17%) of patients. All patients had an initial objective response and 26 (90%) individuals had a sustained complete response. Four (14%) patients had grade 3 leukopenia and two (7%) had grade 3 thrombocytopenia. There were two (7%) non-laboratory-related grade 3 adverse events (one arterial injury and one ascites). The most frequent (>10% patients) grade 1 or 2 adverse events were fatigue (nine [31%]); nausea, vomiting, or anorexia (seven [24%]); abdominal discomfort (six [21%]), leukopenia (nine [31%]), thrombocytopenia (four [14%]), increased alkaline phosphatase (four [14%]), increased alanine or aspartate aminotransferase (four [14%]), increased bilirubin (four [14%]), and decreased albumin (six [21%]). There was one death that was not treatment related.

INTERPRETATION

Radiation segmentectomy was efficacious, with a low proportion of high-grade adverse events in patients with unresectable very early to early stage hepatocellular carcinoma with suboptimal location for ablation. These results suggest that radiation segmentectomy should be further investigated as a potential curative treatment option for well selected patients.

FUNDING

Boston Scientific.

IN.PACT AV Access Randomized Trial: 12-month Clinical Results Demonstrating the Sustained Treatment Effect of Drug-Coated Balloons

PURPOSE

To present twelve-month outcomes of the IN.PACT AV Access Study, a prospective, single-blinded trial enrolling participants with obstructive de novo or restenotic native upper extremity arteriovenous dialysis fistula lesions treated with drug-coated balloon (DCB) or percutaneous transluminal angioplasty (PTA).

MATERIALS AND METHODS

After successful high-pressure PTA, participants at 29 international sites were randomized 1:1 to treatment with IN.PACT AV DCB (n=170) or standard uncoated PTA (n=160). Outcomes at 12 months include target lesion primary patency (TLPP), defined as freedom from clinically-driven target lesion revascularization or access circuit thrombosis, access circuit primary patency (ACPP), number of reinterventions, and adverse events involving the access circuit.

RESULTS

At 12 months, TLPP was 63.8% (90/141) in the DCB group compared to 43.6% (61/140) in the PTA group (p<0.001). The total number of reinterventions required to maintain TLPP through 360 days was 93 in the DCB group and 144 in the PTA group, a 35.4% reduction in reinterventions when DCB was used. Access circuit thrombosis was 2.9% (4/138) in the DCB group and 6.2% (8/129) in the PTA group (p=0.19). Time to TLPP was assessed using a multivariable analysis to identify factors associated with loss of patency. Treatment device was the independent predictor with the largest effect, with a hazard ratio of 0.42 (95%CI [0.29, 0.64]; p<0.001).

CONCLUSION

TLPP was statistically significantly higher in DCB compared to standard PTA at 12 months, demonstrating the sustained and superior effectiveness of this device for the treatment of dysfunctional arteriovenous dialysis fistulas.

Elective fetal reduction by radiofrequency ablation in monochorionic diamniotic twins decreases adverse outcomes compared to ongoing monochorionic diamniotic twins

BACKGROUND

Multifetal pregnancy reduction is a technique used to reduce the fetal number to mitigate the risks of adverse outcomes associated with multiple gestations. Monochorionic diamniotic twin pregnancies are subject to unique complications, contributing to adverse pregnancy outcomes. Thus, patients have an option to electively reduce 1 fetus to improve outcomes.

OBJECTIVE

This study aimed to compare outcomes of elective reduction of monochorionic diamniotic twins by radiofrequency ablation to planned ongoing monochorionic diamniotic twins.

STUDY DESIGN

We performed a retrospective review of 315 monochorionic diamniotic twin gestations that underwent first-trimester ultrasound within 1 institution. Planned electively reduced twins were compared with ongoing monochorionic diamniotic twins. All reductions were performed via radiofrequency ablation of the cord insertion site into the fetal abdomen. The primary outcome was preterm birth at <36 weeks' gestation. Secondary outcomes included gestational age at delivery; preterm birth at less than 37-, 34-, 32-, and 28-weeks' gestation; unintended loss; and adverse perinatal outcomes.

RESULTS

Among 315 monochorionic diamniotic pregnancies, 14 (4.4%) underwent elective multifetal pregnancy reduction, and 301 (95.6%) were planned ongoing twins. The mean gestational age of radiofrequency ablation in the elective multifetal pregnancy reduction group was 15.1±0.68 weeks. Patients who underwent elective multifetal pregnancy reduction had significantly higher maternal age (P<.01) and were more likely to be Asian (P<.01). Moreover, they were more likely to have undergone in vitro fertilization (P=.03) and chorionic villus sampling (P<.01). There was a significantly higher rate of term deliveries in the elective radiofrequency ablation group compared with ongoing twins (gestational age, 38 weeks [interquartile range, 36.1-39.1] vs 35.9 weeks [interquartile range, 34.0-36.9]; P<.01). Patients with ongoing pregnancies had a trend of increased rate of preterm birth at <36 weeks' gestation (odds ratio, 3.4; 95% confidence interval, 1.0-12.0; P=.06), a significantly increased risk of preterm birth at <37 weeks' gestation (odds ratio, 8.0; 95% confidence interval, 2.4-26.4; P<.01), and no difference at less than 34-, 32-, or 28- weeks' gestation. All patients who underwent elective radiofrequency ablation had successful pregnancies with no pregnancy losses or terminations. Of ongoing gestations, 36 required procedures, including 16 (5.3%) medically indicated radiofrequency ablation, 14 (4.6%) laser ablation, and 6 (1.9%) amnioreductions. Furthermore, 22 patients (7.3%) with planned ongoing twins had total pregnancy loss at <24 weeks' gestation. Notably, 12 patients (4.0%) had unintended loss of 1 fetus before 24 weeks' gestation in the ongoing pregnancy cohort, and 12 patients (4.0%) had unintended loss of both fetuses before 24 weeks' gestation. Moreover, 5 patients (1.7%) in the ongoing pregnancy group had intrauterine fetal demise at >24 weeks' gestation and 10 patients (3.3%) electively terminated both fetuses. There was no significant difference in loss rates between the 2 groups.

CONCLUSION

In this study of monochorionic diamniotic twins, patients who elected to undergo multifetal pregnancy reduction had significantly lower rates of preterm birth at <37 weeks and a lower trend of preterm birth at <36 weeks' gestation without an increased risk of pregnancy loss. Median gestational age at delivery was significantly higher in the elective multifetal pregnancy reduction group (38 weeks) than in the ongoing pregnancy group (35.9 weeks). Further research is needed to clarify if multifetal pregnancy reduction improves long-term outcomes.

Interhospital Transfer of Patients With Acute Pulmonary Embolism (PE): Challenges and Opportunities

Acute pulmonary embolism (PE) is associated with significant morbidity and mortality. The management paradigm for acute PE has evolved in recent years with wider availability of advanced treatment modalities ranging from catheter-directed reperfusion therapies to mechanical circulatory support. This evolution has coincided with the development and implementation of institutional pulmonary embolism response teams (PERT) nationwide and internationally. Because most institutions are not equipped or staffed for advanced PE care, patients often require transfer to centers with more comprehensive resources, including PERT expertise. One of the unmet needs in current PE care is an organized approach to the process of interhospital transfer (IHT) of critically ill PE patients. In this review, we discuss medical optimization and support of patients before and during transfer, transfer checklists, defined roles of emergency medical services, and the roles and responsibilities of referring and receiving centers involved in the IHT of acute PE patients.

Considerations for Patients With Peripheral Artery Disease During the COVID-19 Pandemic

New York City was one of the epicenters of the COVID-19 pandemic. The management of peripheral artery disease (PAD) during this time has been a major challenge for health care systems and medical personnel. This document is based on the experiences of experts from various medical fields involved in the treatment of patients with PAD practicing in hospitals across New York City during the outbreak. The recommendations are based on certain aspects including the COVID-19 infection status as well as the clinical PAD presentation of the patient. Our case-based algorithm aims at guiding the treatment of patients with PAD during the pandemic in a safe and efficient way.

Sources of Revenue Loss and Recovery in Radiology Practices During the Coronavirus Disease 2019 (COVID-19) Pandemic

Rationale and Objectives

This study seeks to quantify the financial impact of COVID-19 on radiology departments, and to describe the structure of both volume and revenue recovery.

Materials and Methods

Radiology studies from a large academic health system were retrospectively studied from the first 33 weeks of 2020. Volume and work relative value unit (wRVU) data were aggregated on a weekly basis for three periods: Presurge (weeks 1–9), surge (10–19), and recovery (20–33), and analyzed compared to the pre-COVID baseline stratified by modality, specialty, patient service location, and facility type. Mean and median wRVU per study were used as a surrogate for case complexity.

Results

During the pandemic surge, case volumes fell 57%, while wRVUs fell by 69% relative to the pre-COVID-19 baseline. Mean wRVU per study was 1.13 in the presurge period, 1.03 during the surge, and 1.19 in the recovery. Categories with the greatest mean complexity declines were radiography (−14.7%), cardiothoracic imaging (−16.2%), and community hospitals overall (−15.9%). Breast imaging (+6.5%), interventional (+5.5%), and outpatient (+12.1%) complexity increased. During the recovery, significant increases in complexity were seen in cardiothoracic (0.46 to 0.49), abdominal (1.80 to 1.91), and neuroradiology (2.46 to 2.56) at stand-alone outpatient centers with similar changes at community hospitals. At academic hospitals, only breast imaging complexity remained elevated (1.32 from 1.17) during the recovery.

Conclusion

Reliance on volume alone underestimates the financial impact of the COVID-19 pandemic as there was a disproportionate loss in high-RVU studies. However, increased complexity of outpatient cases has stabilized overall losses during the recovery.

Impact of COVID-19 social distancing regulations on outpatient diagnostic imaging volumes and no-show rates

Background

The coronavirus disease 2019 (COVID-19) pandemic has significantly impacted outpatient radiology practices, necessitating change in practice infrastructure and workflow.

Objective

The purpose of this study was to assess the consequences of social distancing regulations on 1) outpatient imaging volume and 2) no-show rates per imaging modality.

Methods

Volume and no-show rates of a large, multicenter metropolitan healthcare system outpatient practice were retrospectively stratified by modality including radiography, CT, MRI, ultrasonography, PET, DEXA, and mammography from January 2 to July 21, 2020. Trends were assessed relative to timepoints of significant state and local social distancing regulatory changes.

Results

The decline in imaging volume and rise in no-show rates was first noted on March 10, 2020 following the declaration of a state of emergency in New York State (NYS). Total outpatient imaging volume declined 85% from baseline over the following 5 days. Decreases varied by modality: 88% for radiography, 75% for CT, 73% for MR, 61% for PET, 80% for ultrasonography, 90% for DEXA, and 85% for mammography. Imaging volume and no-show rate recovery preceded the mask mandate of April 15, 2020, and further trended along with New York City's reopening phases. No-show rates recovered within 2 months of the height of the pandemic, however, outpatient imaging volume has yet to recover to baseline after 3 months.

Conclusion

The total outpatient imaging volume declined alongside an increase in the no-show rate following the declaration of a state of emergency in NYS. No-show rates recovered within 2 months of the height of the pandemic with imaging volume yet to recover after 3 months.

Clinical impact

Understanding the impact of social distancing regulations on outpatient imaging volume and no-show rates can potentially aid other outpatient radiology practices and healthcare systems in anticipating upcoming changes as the COVID-19 pandemic evolves.

Diagnosis and Treatment of Pulmonary Embolism During the Coronavirus Disease 2019 Pandemic: A Position Paper From the National PERT Consortium

The coexistence of coronavirus disease 2019 (COVID-19) and pulmonary embolism (PE), two life-threatening illnesses, in the same patient presents a unique challenge. Guidelines have delineated how best to diagnose and manage patients with PE. However, the unique aspects of COVID-19 confound both the diagnosis and treatment of PE, and therefore require modification of established algorithms. Important considerations include adjustment of diagnostic modalities, incorporation of the prothrombotic contribution of COVID-19, management of two critical cardiorespiratory illnesses in the same patient, and protecting patients and health-care workers while providing optimal care. The benefits of a team-based approach for decision-making and coordination of care, such as that offered by pulmonary embolism response teams (PERTs), have become more evident in this crisis. The importance of careful follow-up care also is underscored for patients with these two diseases with long-term effects. This position paper from the PERT Consortium specifically addresses issues related to the diagnosis and management of PE in patients with COVID-19.

Bilateral Renal Artery Thrombosis in a Patient With COVID-19

Reports of the incidence of acute kidney injury in patients with coronavirus disease 2019 (COVID-19) have varied greatly from 0.5% to as high as 39%, with onset generally within 7 days from time of admission. The nature of the kidney insult is acute tubular necrosis, immune cell infiltration, or rhabdomyolysis, as demonstrated in autopsy reports. Moreover, infection with COVID-19 has been associated with coagulation abnormalities, as well as complement-mediated generalized thrombotic microvascular injury. These patients have been found to have high D-dimer, fibrin degradation product, and fibrinogen values, an elevated international normalized ratio, normal partial thromboplastin time, and normal platelet count values. Renal artery thrombosis is a rare condition, the most common cause of which is atrial fibrillation. However, bilateral completely occlusive renal artery thrombosis is even rarer. We present a case of a patient with COVID-19 on systemic anticoagulation therapy who presented with a serum creatinine level of 6.04 mg/dL requiring the initiation of kidney replacement therapy and was found to have bilateral renal artery thrombosis.

Safety and Efficacy of Locoregional Treatment during Immunotherapy with Nivolumab for Hepatocellular Carcinoma: A Retrospective Study of 41 Interventions in 29 Patients

PURPOSE

To assess the safety of locoregional treatment (LRT) combined with nivolumab for intermediate and advanced hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

A single-center retrospective review included 29 patients undergoing 41 LRTs-transarterial chemoembolization or yttrium-90 transarterial radioembolization-60 days before or concurrently with nivolumab. Demographic, clinical, and laboratory values and adverse events were reviewed before and after nivolumab initiation and after each LRT. Treatment response and time to progression were assessed using Modified Response Evaluation Criteria in Solid Tumors. Clinical events, including nivolumab termination, death, and time of last follow-up, were assessed.

RESULTS

Over a median nivolumab course of 8.1 months (range, 1.0-30) with a median of 14.2 2-week cycles (range, 1-53), predominantly Child-Pugh A (22/29) patients-12 Barcelona Clinic Liver Cancer (BCLC) B and 17 BCLC C-underwent 20 transarterial chemoembolization and 21 transarterial radioembolization LRTs at a median of 67 days (range, 48-609) after nivolumab initiation. Ten patients underwent multiple LRTs. During a median follow-up of 11.5 months (range, 1.8-35.1), no grade III/IV adverse events attributable to nivolumab were observed. There were five instances of grade III/IV hypoalbuminemia or hyperbilirubinemia within 3 months after LRT. There were no nivolumab-related deaths, and 30-day mortality after LRT was 0%.

CONCLUSIONS

LRTs performed concurrently with nivolumab immunotherapy demonstrate an acceptable safety profile in patients with intermediate and advanced HCC.