Modelling costs of interventional pulmonary embolism treatment: implications of US trends for a European healthcare system.

AIMS: Catheter-directed treatment (CDT) of acute pulmonary embolism (PE) is entering a growth phase in Europe following a steady increase in the USA in the past decade, but the potential economic impact on European healthcare systems remains unknown. METHODS AND RESULTS: We built two statistical models for the monthly trend of proportion of CDT among patients with severe (intermediate- or high-risk) PE in the USA. The conservative model was based on admission data from the National Inpatient Sample (NIS) 2016-20 and the model reflecting increasing access to advanced treatment from the PERT™ national quality assurance database registry 2018-21. By applying these models to the forecast of annual PE-related hospitalizations in Germany, we calculated the annual number of severe PE cases and the expected increase in CDT use for the period 2025-30. The NIS-based model yielded a slow increase, reaching 3.1% (95% confidence interval 3.0-3.2%) among all hospitalizations with PE in 2030; in the PERT-based model, increase would be steeper, reaching 8.7% (8.3-9.2%). Based on current reimbursement rates, we estimated an increase of annual costs for PE-related hospitalizations in Germany ranging from 15.3 to 49.8 million euros by 2030. This calculation does not account for potential cost savings, including those from reduced length of hospital stay. CONCLUSION: Our approach and results, which may be adapted to other European healthcare systems, provide a benchmark for healthcare costs expected to result from CDT. Data from ongoing trials on clinical benefits and cost savings are needed to determine cost-effectiveness and inform reimbursement decisions.

Risk of Mortality Related to Recurrent Limb Events After Endovascular Revascularization of the Superficial Femoral Artery for Peripheral Artery Disease: The Boston Femoral Artery Endovascular Revascularization Outcomes (Boston FAROUT) Study.

Endovascular revascularization of the superficial femoral artery (SFA) may lead to recurrent ischemic syndromes, revascularization, or amputation. The impact of these events on mortality is unknown. We followed all patients having SFA endovascular revascularization for claudication or chronic limb-threatening ischemia in 2 cardiovascular (CV) divisions in Boston, Massachusetts. Any recurrent limb event after the initial SFA revascularization included recurrent claudication (67%), limb ulceration or gangrene (13%), repeat endovascular revascularization (61%), surgical revascularization (15%), or major (9%) or minor amputation (8%). We linked data to the National Death Index to ascertain cause of death grouped into CV mortality, or non-CV mortality. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) from Cox proportional hazards and sub-HRs from Fine-Gray competing risks analyses were clustered by patient. Overall, there were 202 patients with 253 index limb endovascular procedures. A recurrent limb event occurred in 123 limbs (49%) and 93 patients (46%). Patients with and without recurrent limb events had similar numbers of deaths over follow-up (76 [62%] vs 71 [55%], respectively). In multivariable models, recurrent limb event was not related to all-cause death (HR 0.92, 95% CI 0.64 to 1.33), CV death (HR 1.29, 95% CI 0.72 to 1.30), or non-CV death (HR 0.65, CI 0.39 to 1.07). Competing risk analyses suggested male gender and chronic limb-threatening ischemia were more strongly related to CV death, and chronic kidney more strongly related to disease to non-CV death. In conclusion, recurrent limb events, which contribute to patient morbidity, do not increase the risk of all-cause or cause-specific mortality, and should not discourage repeat revascularization to relieve symptoms or ischemia.

Patient and limb outcomes 10 years after endovascular revascularization of the superficial femoral artery for peripheral artery disease: The Boston Femoral Artery Endovascular Revascularization Outcomes (Boston FAROUT) study.

BACKGROUND: We aimed to describe patient and limb outcomes in the decade after endovascular revascularization for chronic lower-extremity peripheral artery disease (PAD). METHODS: We assessed outcomes in patients having endovascular revascularization of the superficial femoral artery in two centers between 2003 and 2011 and followed for a median 9.3 (25-75%: 6.8, 11.1) years. Outcomes included death, myocardial infarction, stroke, repeat limb revascularizations, and amputations. We used competing risks analysis with clustering by patient to determine the hazard ratios (HR) and 95% CI for patients, and procedural characteristics for cause of death, cardiovascular events, and major adverse limb events (MALE). RESULTS: There were 253 index limb revascularizations in 202 patients followed for a median 9.3 years. Patients had intensive medical treatment with 90% on statins and 80% on beta-blockers. During follow up there were 57 (28%) cardiovascular deaths and 62 (31%) noncardiovascular deaths. Of the 253 limbs, 227 (90%) were free of MALE over follow up and 93 (37%) had MALE or minor repeat revascularization. In multivariable models, cardiovascular death significantly associated with critical limb ischemia (HR = 3.21, 95% CI = 1.84, 5.61) and noncardiovascular death with chronic kidney disease (HR = 2.69, 95% CI = 1.68, 4.30), and smoking (HR = 2.75, 95% CI = 1.01, 7.52). MALE or minor repeat revascularization associated with critical limb ischemia (HR = 1.43, 95% CI = 0.84, 2.43), smoking (HR = 2.49, 95% CI = 1.26, 4.90), and lesion length > 200 mm (HR = 1.51, 95% CI = 0.98, 2.33). CONCLUSIONS: Among patients with intensive medical therapy, the risk of noncardiovascular death was high and similar to cardiovascular death. Endovascular intervention can have acceptable long-term results. Future studies should evaluate strategies to reduce both cardiovascular and noncardiovascular deaths.

A Multimodality Imaging Approach to Defining Risk in Patients With Acute Pulmonary Embolism.

BACKGROUND: Morbidity and mortality for acute pulmonary embolism (PE) remain high. Therapies such as catheter-directed thrombolysis may improve outcomes, but these are generally reserved for higher-risk patients. Imaging may help guide the use of the newer therapies, but current guidelines focus more on clinical factors. Our goal was to create a risk model that incorporated quantitative echocardiographic and computed tomography (CT) measures of right ventricular (RV) size and function, thrombus burden, and serum biomarkers of cardiac overload or injury. METHODS: This was a retrospective study of 150 patients evaluated by a PE response team. Echocardiography was performed within 48 hours of diagnosis. Computed tomography measures included RV/left ventricular (LV) ratio and thrombus load (Qanadli score). Echocardiography was used to obtain various quantitative measures of RV function. We compared characteristics of those who met the primary endpoint (7-day mortality and clinical deterioration) to those who did not. Receiver operating curve analysis was used to assess the performance of different combinations of clinically relevant features and the association with adverse outcomes. RESULTS: Fifty-two percent of patients were female, with age 62 ± 17 years, systolic blood pressure 123 ± 25 mm Hg, heart rate 98 ± 19, troponin 3.2 ± 35 ng/dL, and b-type natriuretic peptide (BNP) 467 ± 653. Fourteen (9.3%) were treated with systemic thrombolytics, 27 (18%) underwent catheter-directed thrombolytics, 23 (15%) were intubated or required vasopressors, and 14 (9.3%) died. Patients who met the primary endpoint (44%) versus those who did not (56%) had lower RV S' (6.6 vs 11.9 cm/sec; P < .001) and RV free wall strain (-10.9% vs -13.6%; P = .005), higher RV/LV ratio on CT, and higher serum BNP and troponin levels. Receiver operating curve analysis demonstrated an area under the curve of 0.89 for a model that included RV S', RV free wall strain and tricuspid annular plane systolic excursion/RV systolic pressure ratio from echo, thrombus load and RV/LV ratio from CT, and troponin and BNP levels. CONCLUSION: A combination of clinical, echo, and CT findings that reflect the hemodynamic effects of the embolism identified patients with adverse events related to acute PE. Optimized scoring systems that focus on reversible abnormalities attributable to PE may allow more appropriate triaging of intermediate- to high-risk patients with PE for early interventional strategy.

Endovascular Ultrasound Renal Denervation to Treat Hypertension: The RADIANCE II Randomized Clinical Trial.

Importance: Two initial sham-controlled trials demonstrated that ultrasound renal denervation decreases blood pressure (BP) in patients with mild to moderate hypertension and hypertension that is resistant to treatment. Objective: To study the efficacy and safety of ultrasound renal denervation without the confounding influence of antihypertensive medications in patients with hypertension. Design, Setting, and Participants: Sham-controlled, randomized clinical trial with patients and outcome assessors blinded to treatment assignment that was conducted between January 14, 2019, and March 25, 2022, at 37 centers in the US and 24 centers in Europe, with randomization stratified by center. Patients aged 18 years to 75 years with hypertension (seated office systolic BP [SBP] ≥140 mm Hg and diastolic BP [DBP] ≥90 mm Hg despite taking up to 2 antihypertensive medications) were eligible if they had an ambulatory SBP/DBP of 135/85 mm Hg or greater and an SBP/DBP less than 170/105 mm Hg after a 4-week washout of their medications. Patients with an estimated glomerular filtration rate of 40 mL/min/1.73 m2 or greater and with suitable renal artery anatomy were randomized 2:1 to undergo ultrasound renal denervation or a sham procedure. Patients were to abstain from antihypertensive medications until the 2-month follow-up unless prespecified BP criteria were exceeded and were associated with clinical symptoms. Interventions: Ultrasound renal denervation vs a sham procedure. Main Outcomes and Measures: The primary efficacy outcome was the mean change in daytime ambulatory SBP at 2 months. The primary safety composite outcome of major adverse events included death, kidney failure, and major embolic, vascular, cardiovascular, cerebrovascular, and hypertensive events at 30 days and renal artery stenosis greater than 70% detected at 6 months. The secondary outcomes included mean change in 24-hour ambulatory SBP, home SBP, office SBP, and all DBP parameters at 2 months. Results: Among 1038 eligible patients, 150 were randomized to ultrasound renal denervation and 74 to a sham procedure (mean age, 55 years [SD, 9.3 years]; 28.6% female; and 16.1% self-identified as Black or African American). The reduction in daytime ambulatory SBP was greater with ultrasound renal denervation (mean, -7.9 mm Hg [SD, 11.6 mm Hg]) vs the sham procedure (mean, -1.8 mm Hg [SD, 9.5 mm Hg]) (baseline-adjusted between-group difference, -6.3 mm Hg [95% CI, -9.3 to -3.2 mm Hg], P < .001), with a consistent effect of ultrasound renal denervation throughout the 24-hour circadian cycle. Among 7 secondary BP outcomes, 6 were significantly improved with ultrasound renal denervation vs the sham procedure. No major adverse events were reported in either group. Conclusions and Relevance: In patients with hypertension, ultrasound renal denervation reduced daytime ambulatory SBP at 2 months in the absence of antihypertensive medications vs a sham procedure without postprocedural major adverse events. Trial Registration: ClinicalTrials.gov Identifier: NCT03614260.

Stent imaging on a clinical dual-source photon-counting detector CT system-impact of luminal attenuation and sharp kernels on lumen visibility.

OBJECTIVES: To assess the impact of scan modes and reconstruction kernels using a novel dual-source photon-counting detector CT (PCD-CT) on lumen visibility and sharpness of different stent sizes. METHODS: A phantom containing six balloon-expandable stents (2.5 to 9 mm diameter) in silicone tubing was scanned on a PCD-CT with standard (0.6 mm and 0.4 mm thicknesses) and ultra-high-resolution (0.2 mm thickness) modes. With the use of increasing contrast medium concentrations, densities of 0, 200, 400, and 600 HU were achieved. Standard-resolution scans were reconstructed using increasing sharpness kernels, using both polyenergetic quantitative soft tissue "conventional" ((Qr40c(0.6 mm), Qr40c(0.4 mm), Qr72c(0.2 mm)) and vascular (Bv) virtual monoenergetic reconstructions (Bv44m(0.4 mm), Bv60m(0.4 mm)) at 70 keV. In-stent lumen visibility, sharpness (max. ΔHU of the stent measured in profile plots), and in-stent noise (standard deviation of HU) were measured. RESULTS: In-stent lumen visibility was highest for Qr72c(0.2 mm) (86.5 ± 2.8% to 88.3 ± 2.6%) and in Bv60m(0.4 mm) reconstructions (77.3 ± 2.9 to 82.7 ± 2.5%). Lumen visibility was lowest in the smallest stent (2.5 mm) ranging from 54.1% in Qr40c(0.6 mm) to 74.1% in Qr72c(0.2 mm) and highest in the largest stent (9 mm) ranging from 93.8% in Qr40c(0.6 mm) to 99.1% in the Qr72c(0.2 mm) series. Lumen visibility decreased by 2.1% for every 200-HU increase in lumen attenuation. Max. ΔHU between stents and stent lumen was highest in Qr72c(0.2 mm) (ΔHU 892 ± 504 to 1526 ± 517) and Bv60m(0.4 mm) series (ΔHU 480 ± 357 to 1030 ± 344). Improvement of lumen visibility and sharpness in UHR and Bv60m(0.4 mm) series was strongest in smaller stent sizes. CONCLUSION: UHR acquisition mode and sharp reconstruction kernels on a novel PCD-CT system significantly improve in-stent lumen visibility and sharpness-especially for smaller stent sizes. KEY POINTS: • In-stent lumen visibility and sharpness of stents significantly improve using sharp reconstruction kernels (Bv60) and ultra-high-resolution mode in photon-counting detector computed tomography. • The observed improvement of stent-lumen visibility was highest in smaller stent sizes.

Inari large-bore mechanical thrombectomy in intermediate-high risk submassive PE patients: Case series and literature review.

Pulmonary embolism (PE) is one of the most common causes of cardiovascular (CV) mortality worldwide. Owing to the associated morbidity and mortality with other treatment modalities, including systemic thrombolysis, a discernible change in the era of acute pulmonary embolism management has been reported. Catheter-directed thrombectomy using the FlowTriever system (Inari Medical; Irvine, CA, USA) was shown to reduce endpoints of interest in patients with acute intermediate-high risk PE and was associated with rapid hemodynamic improvement. In this report, we describe our experience with three cases of patients presenting with submassive PE, whereby immediate pulmonary artery pressure improvement was evident in all cases after successful mechanical thrombectomy. Our experience supports the use of FlowTriever mechanical thrombectomy for the treatment of submassive PE in clinical practice, with a call for further research to establish associated benefits.

Quiescent-Interval Slice-Selective MRA Accurately Estimates Intravascular Stent Dimensions Prior to Intervention in Patients With Peripheral Artery Disease.

BACKGROUND: Quiescent-interval slice-selective (QISS) magnetic resonance angiography (MRA) is a non-contrast alternative for the pre-procedural assessment of patients with peripheral artery disease (PAD). However, the feasibility of pre-procedural stent size estimation using QISS MRA would merit investigation. PURPOSE: To evaluate the feasibility of QISS MRA for pre-procedural stent size estimation in PAD patients compared to computed tomography angiography (CTA). STUDY TYPE: Retrospective. SUBJECTS: Thirty-three PAD patients (68 ± 9 years, 18 men, 15 women). FIELD STRENGTH/SEQUENCE: Two-dimensional balanced steady-state free precession QISS MRA at 1.5 T and 3 T. ASSESSMENT: All patients received QISS MRA and CTA of the lower extremity run-off followed by interventional digital subtraction angiography (DSA). Stenotic lesion length and diameter were quantified (AMF and AVS with 3 and 13 years of experience in cardiovascular imaging, respectively) to estimate the dimensions of the stent necessary to restore blood flow in the treated arteries. Measured dimensions were adjusted to the closest stent size available. STATISTICAL TESTS: The Friedman test with subsequent pairwise Wilcoxon signed-rank test was used to compare the estimated stent dimensions between QISS MRA, CTA, and the physical stent size used for intervention. Intra-class correlation (ICC) analysis was performed to assess inter-reader agreement. Significant differences were considered at P < 0.05. RESULTS: No significant difference was observed between estimated stent diameter by QISS MRA or CTA compared to physical stent diameter (8.9 ± 2.9 mm, 8.8 ± 3.0 mm, and 8.8 ± 3.8 mm, respectively; χ2  = 1.45, P = 0.483). There was a significant underestimation of stent length for both QISS MRA and CTA, compared to physical stent length (45.8 ± 27.8 mm, 46.4 ± 29.3 mm, and 50.4 ± 34.0 mm, respectively; χ2  = 11.96) which could be corrected when measurements were adjusted to the next available stent length (χ2  = 2.38, P = 0.303). Inter-reader assessment showed good to excellent agreement between the readers (all ICC ≥0.81). DATA CONCLUSION: QISS MRA represents a reliable method for pre-procedural lesion assessment and stent diameter and length estimation in PAD patients. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

Comparison of 2D and 3D quiescent-interval slice-selective non-contrast MR angiography in patients with peripheral artery disease.

OBJECTIVE: To evaluate the potential clinical benefit of the superior spatial resolution of 3D prototype thin-slab stack-of-stars (tsSOS) quiescent-interval slice-selective (QISS) MRA over standard 2D-QISS MRA for the detection peripheral artery disease (PAD), using computed tomography angiography (CTA) as reference. MATERIALS AND METHODS: Twenty-three patients (70 ± 8 years, 18 men) with PAD who had previously undergone run-off CTA were prospectively enrolled. Patients underwent non-contrast MRA using 2D-QISS and tsSOS-QISS at 1.5 T. Eighteen arterial segments were evaluated for subjective and objective image quality (normalized signal-to-noise, nSNR), vessel sharpness, and area under the curve (AUC) for > 50% stenosis detection. RESULTS: Overall subjective image quality ratings for the entire run-off were not different between tsSOS-QISS and 2D-QISS (3 [3; 4] vs 4 [3; 4], respectively; P = 0.813). Sharpness of primary branch vessels demonstrated improved image quality using tsSOS-QISS compared with 2D-QISS (4 [3; 4] vs 3 [2; 3], P = 0.008). Objective image quality measures were not different between 2D-QISS and tsSOS-QISS (nSNR 5.0 ± 1.9 vs 4.2 ± 1.8; P = 0.132). AUCs for significant stenosis detection by tsSOS-QISS and 2D-QISS were 0.877 and 0.856, respectively (P = 0.336). DISCUSSION: The prototype 3D tsSOS-QISS technique provides similar accuracy in patients with PAD to a standard commercially available 2D-QISS technique, indicating that the use of relatively thick slices does not limit the diagnostic performance of 2D-QISS. However, subjective image quality for branch vessel depiction is improved using the 3D approach.

Aggressive Therapy for Acute Pulmonary Embolism: Systemic Thrombolysis and Catheter-Directed Approaches.

Venous thromboembolism (VTE) is the third most common cause of cardiovascular disease after myocardial infarction and stroke. Population-based studies estimate that up to 94,000 new cases of pulmonary embolism (PE) occur in the United States annually with an increasing incidence with age. Mortality from PE is the greatest in the first 24 hours, with a decreased survival extending out 3 months. Thus, acute PE is a potentially fatal illness if not recognized and treated in a timely manner. Contemporary management includes systemic anticoagulation, thrombolysis, catheter-based procedures, and surgical embolectomy. This article reviews current clinical evidence and societal guidelines for the use of systemic and catheter-directed thrombolysis for treatment of acute PE.

Diagnostic accuracy of non-contrast quiescent-interval slice-selective (QISS) MRA combined with MRI-based vascular calcification visualization for the assessment of arterial stenosis in patients with lower extremity peripheral artery disease.

OBJECTIVES: The proton density-weighted, in-phase stack-of-stars (PDIP-SOS) MRI technique provides calcification visualization in peripheral artery disease (PAD). This study sought to investigate the diagnostic accuracy of a combined non-contrast quiescent-interval slice-selective (QISS) MRA and PDIP-SOS MRI protocol for the detection of PAD, in comparison with CTA and digital subtraction angiography (DSA). METHODS: Twenty-six prospectively enrolled PAD patients (70 ± 8 years) underwent lower extremity CTA and 1.5-T or 3-T PDIP-SOS/QISS MRI prior to DSA. Two readers rated image quality and graded stenosis (≥ 50%) on QISS MRA without/with calcification visualization. Sensitivity, specificity, and area under the curve (AUC) were calculated against DSA. Calcification was quantified and compared between MRI and non-contrast CT (NCCT) using paired t test, Pearson's correlation, and Bland-Altman analysis. RESULTS: Image quality ratings were significantly higher for CTA compared to those for MRA (4.0 [3.0-4.0] and 3.0 [3.0-4.0]; p = 0.0369). The sensitivity and specificity of QISS MRA, QISS MRA with PDIP-SOS, and CTA for ≥ 50% stenosis detection were 85.4%, 92.2%, and 90.2%, and 90.3%, 93.2%, and 94.2%, respectively, while AUCs were 0.879, 0.928, and 0.923, respectively. A significant increase in AUC was observed when PDIP-SOS was added to the MRA protocol (p = 0.0266). Quantification of calcification showed significant differences between PDIP-SOS and NCCT (80.6 ± 31.2 mm3 vs. 88.0 ± 29.8 mm3; p = 0.0002) with high correlation (r = 0.77, p < 0.0001) and moderate mean of differences (- 7.4 mm3). CONCLUSION: QISS MRA combined with PDIP-SOS MRI provides improved, CTA equivalent, accuracy for the detection of PAD, although its image quality remains inferior to CTA. KEY POINTS: • Agreement in stenosis detection rate using non-contrast quiescent-interval slice-selective MRA compared to DSA improved when calcification visualization was provided to the readers. • An increase was observed in both sensitivity and specificity for the detection of ≥ 50% stenosis when MRI-based calcification assessment was added to the protocol, resulting in a diagnostic accuracy more comparable to CTA. • Quantification of calcification showed statistical difference between MRI and non-contrast CT; however, a high correlation was observed between the techniques.

Comparison of 4 Acute Pulmonary Embolism Mortality Risk Scores in Patients Evaluated by Pulmonary Embolism Response Teams.

Importance: The risk of death from acute pulmonary embolism can range as high as 15%, depending on patient factors at initial presentation. Acute treatment decisions are largely based on an estimate of this mortality risk. Objective: To assess the performance of risk assessment scores in a modern, US cohort of patients with acute pulmonary embolism. Design, Setting, and Participants: This multicenter cohort study was conducted between October 2016 and October 2017 at 8 hospitals participating in the Pulmonary Embolism Response Team (PERT) Consortium registry. Included patients were adults who presented with acute pulmonary embolism and had sufficient information in the medical record to calculate risk scores. Data analysis was performed from March to May 2020. Main Outcomes and Measures: All-cause mortality (7- and 30-day) and associated discrimination were assessed by the area under the receiver operator curve (AUC). Results: Among 416 patients with acute pulmonary embolism (mean [SD] age, 61.3 [17.6] years; 207 men [49.8%]), 7-day mortality in the low-risk groups ranged from 1.3% (1 patient) to 3.1% (4 patients), whereas 30-day mortality ranged from 2.6% (1 patient) to 10.2% (13 patients). Among patients in the highest-risk groups, the 7-day mortality ranged from 7.0% (18 patients) to 16.3% (7 patients), whereas 30-day mortality ranged from 14.4% (37 patients) to 26.3% (26 patients). Each of the risk stratification tools had modest discrimination for 7-day mortality (AUC range, 0.616-0.666) with slightly lower discrimination for 30-day mortality (AUC range, 0.550-0.694). Conclusions and Relevance: These findings suggest that commonly used risk tools for acute pulmonary embolism have modest estimating ability. Future studies to develop and validate better risk assessment tools are needed.

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.

Permanent inferior vena cava filters offer greater expected patient utility at lower predicted cost.

OBJECTIVE: Retrievable inferior vena cava (IVC) filters were first approved for use in the United States in 2003 to address the long-term complications of migration, thrombosis, fracture, and perforation observed with permanent IVC filter implantation. Although Food and Drug Administration approval of retrievable IVC filters includes permanent implantation, the incidence of complications from long-term implantation appears to be greater than that reported with existing permanent IVC filters. Also, only a small fraction of such retrievable IVC filters are ever retrieved. The purpose of the present study was to determine the threshold retrieval rate at which the use of retrievable IVC filters could be justified. METHODS: A Markov decision tree was constructed comparing retrievable and permanent IVC filters regarding their effectiveness and cost. A review of the reported data provided outcome probabilities, and the Tufts Medical Center Cost-Effectiveness Analysis Registry was the source of the utility values for the various potential outcomes. Medicare reimbursement rates served as a proxy for costs. A sensitivity analysis was performed for various parameters, primarily to determine the retrieval rate threshold at which the use of retrievable IVC filters would outperform the use of permanent IVC filters. RESULTS: Base case analysis demonstrated a greater predicted effectiveness for permanent compared with retrievable IVC filter implantation (5.41 quality-adjusted life-years [QALY] vs 5.33 QALY) at a lower cost ($2070 vs $4650). Monte Carlo simulation at 10,000 iterations confirmed the expected utility (5.4 ± 3.0 QALY vs 5.3 ± 3.0 QALY; P = .0002) and cost ($1900 ± $7400 vs $4800 ± 9900; P < .0001) to be statistically superior for permanent IVC filters. A sensitivity analysis for the filter retrieval rate demonstrated that the strategy of using a retrievable IVC filter was never preferable for utility or cost. The superiority of permanent IVC filter placement for effectiveness and cost persisted, regardless of anticipated patient-predicted annual mortality. A two-way sensitivity analysis for both IVC filter removal rate and annual patient mortality confirmed the superiority of permanent IVC filter placement at all levels. CONCLUSIONS: The predicted effectiveness of permanent IVC filters was greater and the predicted cost lower than those for retrievable IVC filters, regardless of the IVC filter retrieval rate. This interpretation of existing reported data using Markov decision analysis modeling supports the argument that unless the long-term complication rate of retrievable IVC filters can be significantly improved, their use should be abandoned in favor of currently available permanent IVC filters.

Free-Breathing Fast Low-Angle Shot Quiescent-Interval Slice-Selective Magnetic Resonance Angiography for Improved Detection of Vascular Stenoses in the Pelvis and Abdomen: Technical Development.

OBJECTIVES: Balanced steady-state free precession-based quiescent-interval slice-selective (bSSFP QISS) magnetic resonance angiography (MRA) is accurate for the noncontrast evaluation of peripheral arterial disease (PAD); however, drawbacks include the need for breath-holding when imaging the abdomen and pelvis, and sensitivity to off-resonance artifacts. The purpose of this study was to evaluate the image quality and diagnostic accuracy in the pelvis and abdomen of free-breathing fast low-angle shot-based QISS (FLASH QISS) techniques in comparison to bSSFP QISS in patients with PAD, using computed tomographic angiography as the reference. MATERIALS AND METHODS: Twenty-seven patients (69 ± 10 years, 17 men) with PAD were enrolled in this institutional review board-approved, Health Insurance Portability and Accountability Act-compliant prospective study between April and December 2018. Patients underwent noncontrast MRA using standard bSSFP QISS and prototype free-breathing radial-FLASH and Cartesian-FLASH QISS at 3 T. A subset of patients (n = 22) also underwent computed tomographic angiography as the reference standard. Nine arterial segments per patient were evaluated spanning the abdomen, pelvis, and upper thigh regions. Objective (signal intensity ratio and relative standard deviation) and subjective image quality (4-point scale) and stenosis (>50%) were evaluated by 2 readers and compared using one-way analysis of variance, Wilcoxon, and McNemar tests, respectively. RESULTS: A total of 179 vascular segments were available for analysis by all QISS techniques. No significant difference was observed among bSSFP, radial-FLASH, and Cartesian-FLASH QISS techniques in signal intensity ratio (P = 0.428) and relative standard deviation (P = 0.220). Radial-FLASH QISS demonstrated the best image quality (P < 0.0001) and the highest interreader agreement (κ = 0.721). The sensitivity values of bSSFP, radial-FLASH, and Cartesian-FLASH QISS for the detection of greater than 50% stenosis were 76.0%, 84.0%, and 80.0%, respectively, whereas specificity values were 97.6%, 94.0%, and 92.8%, respectively. Moreover, FLASH QISS consistently reduced off-resonance artifacts compared with bSSFP QISS. CONCLUSIONS: Free-breathing FLASH QISS MRA techniques provide improved image quality and sensitivity, high specificity, and reduced off-resonance artifacts for vascular stenosis detection in the abdomen and pelvis.

Rate of major adverse renal or cardiac events with iohexol compared to other low osmolar contrast media during interventional cardiovascular procedures.

OBJECTIVE: This study assessed the rate of major adverse renal or cardiac events (MARCE) when iohexol is used during interventional cardiovascular procedures compared to other low osmolar contrast media (LOCMs). BACKGROUND: Interventional cardiovascular procedures are often essential for diagnosis and treatment, the risk of MARCE should be considered. METHODS: Data were derived from the Premier Hospital Database January 1, 2010 through September 30, 2015. Patient encounters with an inpatient primary interventional cardiovascular procedure with a single LOCM (iohexol, ioversol, ioxilan, ioxaglate, or iopamidol) were included. The primary outcome was a composite endpoint of MARCE, which included: renal failure with dialysis, acute kidney injury (AKI) with or without dialysis, contrast induced AKI, acute myocardial infarction, angina, stent occlusion/thrombosis, stroke, transient ischemic attack, or death. Multivariable regression analysis was performed using the hospital fixed-effects specification to assess the relationship between MARCE and iohexol compared to other LOCMs, while controlling for patient demographics, comorbid conditions and reason for hospitalization. As a sensitivity analysis, direct comparisons of iohexol were made to other LOCMs. RESULTS: A total of 458,091 inpatient encounters met inclusion criteria of which 26% used iohexol and 74% used other LOCMs. Results of multivariable modeling revealed no differences in MARCE rates between iohexol and other LOCMs. When direct comparisons of iohexol vs. ioversol and iopamidol were modeled, no differences in MARCE nor the renal component of MARCE were found. CONCLUSIONS: In this retrospective multicenter study, there were no differences in MARCE events with iohexol compared to other LOCMs during inpatient interventional cardiovascular procedures.

Treatment of submassive and massive pulmonary embolism: a clinical practice survey from the second annual meeting of the Pulmonary Embolism Response Team Consortium.

There is a paucity of robust clinical trial data to guide the treatment of acute pulmonary embolism (PE) thus the clinical guidelines rely heavily on expert opinion. Pulmonary Embolism Response Teams (PERT) have been developed to streamline the care of patients with acute PE. We conducted a survey among 100 experts in the field of PE during the second annual meeting of the PERT Consortium. Respondents were queried with respect to their demographic information, clinical practice questions and clinical vignettes. Clinical practice questions were focused questions about the risk stratification and treatment of patients with acute submassive PE, anticoagulation strategies for patients receiving thrombolysis and the use of inferior vena cava filters. Clinical vignettes were designed to assess participants' preferred choice of treatment for a variety of commonly encountered clinical scenarios. Among physicians affiliated with a PERT, there is overall agreement with regards to the criteria used for risk classification of patients with PE and its application to patients in the provided clinical vignettes. In contrast, there is substantial variability in the treatment strategies of patients presenting with commonly encountered clinical scenarios. The results of this survey highlight the need for more clinical trial data along with accepted algorithms for treatment of acute PE. In the absence of this, PERTs can facilitate multidisciplinary discussions in order to standardize treatment and provide evidence-based therapies to patients with acute PE.

Iso-osmolar contrast media and adverse renal and cardiac events after percutaneous cardiovascular intervention.

AIM: To assess the relationship between type of contrast media (CM), iso-osmolar contrast media (IOCM) or low-osmolar contrast media (LOCM), and major adverse renal and cardiovascular events (MARCE). MATERIALS & METHODS: Coronary or peripheral angioplasty visits were stratified into CM cohorts: IOCM or LOCM. Multivariable regression analysis used hospital fixed effects to assess the relationship between MARCE events and type of CM. RESULTS: Among 333,533 visits (357 hospitals), the incidence of MARCE was 7.41%. After controlling for observable and unobservable time invariant within-hospital characteristics, administration of IOCM versus LOCM was associated with a 0.69% absolute and 9.32% relative risk reduction in MARCE rate. CONCLUSION: Our study indicates that as compared with LOCM, IOCM may be associated with reduction of MARCE events in coronary or peripheral angioplasty patients.

The effect of major adverse renal cardiovascular event (MARCE) incidence, procedure volume, and unit cost on the hospital savings resulting from contrast media use in inpatient angioplasty.

OBJECTIVE: To determine the net economic impact of switching from low-osmolar contrast media (LOCM) to iso-osmolar contrast media (IOCM; iodixanol) in patients undergoing inpatient coronary or peripheral angioplasty in the United States (US). METHODS: A budget impact model (BIM) was developed from a hospital perspective. Nationally representative procedural and contrast media prevalence rates, along with MARCE (major adverse renal cardiovascular event) incidence and episode-related cost data were derived from Premier Hospital Data (October 2014 to September 2015). A previously estimated relative risk reduction in MARCE associated with IOCM usage (9.3%) was applied. The higher cost of IOCM was included when calculating the net impact estimates at the aggregate, hospital type, and per hospital levels. One-way (±25%) and probabilistic sensitivity analyses identified the model's most important inputs. RESULTS: Based on weighted analysis, 513,882 US inpatient angioplasties and 35,610 MARCE cases were estimated annually. Switching to an "IOCM only" strategy from a "LOCM only" strategy increases contrast media cost, but prevents 2,900 MARCE events. The annual budget impact was an estimated saving of $30.71 million, aggregated across all US hospitals, $6,316 per hospital, or $60 per procedure. Net savings were maintained across all univariate sensitivity analyses. While MARCE/event-free cost differential was the most important factor driving total net savings for hospitals in the Northeast and West, procedural volume was important in the Midwest and rural locations. CONCLUSIONS: Switching to an "IOCM only" strategy from a "LOCM only" approach yields substantial net global savings to hospitals, both at the national level and within hospital sub-groups. Hospital administrators should maintain awareness of the factors that are likely to be more influential for their hospital and recognize that purchasing on the basis of lower contrast media cost may result in higher overall costs for patients undergoing inpatient angioplasty.