A Blueprint for Multi-use Disease Modeling in Health Economics: Results from Two Expert-Panel Consultations

BACKGROUND

The current use of health economic decision models in HTA is mostly confined to single use cases, which may be inefficient and result in little consistency over different treatment comparisons, and consequently inconsistent health policy decisions, for the same disorder. Multi-use disease models (MUDMs) (other terms: generic models, whole disease models, disease models) may offer a solution. However, much is uncertain about their definition and application. The current research aimed to develop a blueprint for the application of MUDMs.

METHODS

We elicited expert opinion using a two-round modified Delphi process. The panel consisted of experts and stakeholders in health economic modelling from various professional backgrounds. The first questionnaire concerned definition, terminology, potential applications, issues and recommendations for MUDMs and was based on an exploratory scoping review. In the second round, the panel members were asked to reconsider their input, based on feedback regarding first-round results, and to score issues and recommendations for priority. Finally, adding input from external advisors and policy makers in a structured way, an overview of issues and challenges was developed during two team consensus meetings.

RESULTS

In total, 54 respondents contributed to the panel results. The term 'multi-use disease models' was proposed and agreed upon, and a definition was provided. The panel prioritized 10 potential applications (with comparing alternative policies and supporting resource allocation decisions as the top 2), while 20 issues (with model transparency and stakeholders' roles as the top 2) were identified as challenges. Opinions on potential features concerning operationalization of multi-use models were given, with 11 of these subsequently receiving high priority scores (regular updates and revalidation after updates were the top 2).

CONCLUSIONS

MUDMs would improve on current decision support regarding cost-effectiveness information. Given feasibility challenges, this would be most relevant for diseases with multiple treatments, large burden of disease and requiring more complex models. The current overview offers policy makers a starting point to organize the development, use, and maintenance of MUDMs and to support choices concerning which diseases and policy decisions they will be helpful for.

Implementation of Whole-Genome and Transcriptome Sequencing Into Clinical Cancer Care

PURPOSE

The combination of whole-genome and transcriptome sequencing (WGTS) is expected to transform diagnosis and treatment for patients with cancer. WGTS is a comprehensive precision diagnostic test that is starting to replace the standard of care for oncology molecular testing in health care systems around the world; however, the implementation and widescale adoption of this best-in-class testing is lacking.

METHODS

Here, we address the barriers in integrating WGTS for cancer diagnostics and treatment selection and answer questions regarding utility in different cancer types, cost-effectiveness and affordability, and other practical considerations for WGTS implementation.

RESULTS

We review the current studies implementing WGTS in health care systems and provide a synopsis of the clinical evidence and insights into practical considerations for WGTS implementation. We reflect on regulatory, costs, reimbursement, and incidental findings aspects of this test.

CONCLUSION

WGTS is an appropriate comprehensive clinical test for many tumor types and can replace multiple, cascade testing approaches currently performed. Decreasing sequencing cost, increasing number of clinically relevant aberrations and discovery of more complex biomarkers of treatment response, should pave the way for health care systems and laboratories in implementing WGTS into clinical practice, to transform diagnosis and treatment for patients with cancer.

Clinical utility of whole-genome sequencing in precision oncology

Precision diagnostics is one of the two pillars of precision medicine. Sequencing efforts in the past decade have firmly established cancer as a primarily genetically driven disease. This concept is supported by therapeutic successes aimed at particular pathways that are perturbed by specific driver mutations in protein-coding domains and reflected in three recent FDA tissue agnostic cancer drug approvals. In addition, there is increasing evidence from studies that interrogate the entire genome by whole-genome sequencing that acquired global and complex genomic aberrations including those in non-coding regions of the genome might also reflect clinical outcome. After addressing technical, logistical, financial and ethical challenges, national initiatives now aim to introduce clinical whole-genome sequencing into real-world diagnostics as a rational and potentially cost-effective tool for response prediction in cancer and to identify patients who would benefit most from 'expensive' targeted therapies and recruitment into clinical trials. However, so far, this has not been accompanied by a systematic and prospective evaluation of the clinical utility of whole-genome sequencing within clinical trials of uniformly treated patients of defined clinical outcome. This approach would also greatly facilitate novel predictive biomarker discovery and validation, ultimately reducing size and duration of clinical trials and cost of drug development. This manuscript is the third in a series of three to review and critically appraise the potential and challenges of clinical whole-genome sequencing in solid tumors and hematological malignancies.

Cost-effectiveness of a multidisciplinary lifestyle-enhancing treatment for inpatients with severe mental illness: the MULTI study V

Introduction

Economic evaluations of lifestyle interventions for people with mental illness are needed to inform policy makers and managers about implementing such interventions and corresponding reforms in routine mental healthcare.

Objectives

We aimed to evaluate changes in healthcare costs 18 months after the implementation of a multidisciplinary lifestyle-enhancing treatment for inpatients with severe mental illness (MULTI) versus treatment as usual (TAU).

Methods

In a cohort study (n=114; 65 MULTI, 49 TAU), we retrospectively retrieved cost data in Euros on all patient sessions, ward stay, medication use, and hospital referrals in the quarter year at the start of MULTI (Q1 2014) and after its evaluation (Q3 2015). We used linear regression analyses correcting for baseline values and differences between groups, calculated quality-adjusted life years (QALY) and deterministic incremental cost-effectiveness ratios, and performed probabilistic sensitivity analyses.

Results

Adjusted regression showed reduced total costs per patient per quarter year in favor of MULTI (B=-736.30, 95%CI: -2145.2–672.6). Corresponding probabilistic sensitivity analysis accounting for uncertainty surrounding the parameters showed MULTI was dominant over TAU with a saving in total costs of €417.48 (95%-CI: -2,873.2–2,042.1) against 0.06 improvement in QALY (95%-CI: -0.08–0.20). Costs saving estimates were statistically non-significant showing wide confidence intervals.

Conclusions

Regardless of cost savings, MULTI did not increase healthcare costs while improving QALY and additional previously observed health outcomes. This indicates that starting lifestyle interventions does not need to be hampered by costs. Potential societal and economic value may justify investment to support implementation and maintenance. Further research is needed to study this hypothesis.

Disclosure

No significant relationships.

Early technology assessment of using whole genome sequencing in personalized oncology

Introduction: Personalized medicine-based treatments in advanced cancer hold the promise to offer substantial health benefits to genetic subgroups, but require efficient biomarker-based patient stratification to match the right treatment and may be expensive. Standard molecular diagnostics are currently very heterogeneous, and tests are often performed sequentially. The alternative to whole genome sequencing (WGS) i.e. simultaneously testing for all relevant DNA-based biomarkers thereby allowing immediate selection of the most optimal therapy, is more costly than current techniques. In the current implementation stage, it is important to explore the added value and cost-effectiveness of using WGS on a patient level and to assess optimal introduction of WGS on the level of the healthcare system.Areas covered: First, an overview of current worldwide initiatives concerning the use of WGS in clinical practice for cancer diagnostics is given. Second, a comprehensive, early health technology assessment (HTA) approach of evaluating WGS in the Netherlands is described, relating to the following aspects: diagnostic value, WGS-based treatment decisions, assessment of long-term health benefits and harms, early cost-effectiveness modeling, nation-wide organization, and Ethical, Legal and Societal Implications.Expert opinion: This study provides evidence to guide further development and implementation of WGS in clinical practice and the healthcare system.

SAFE@HOME: Cost analysis of a new care pathway including a digital health platform for women at increased risk of preeclampsia

OBJECTIVE

To perform a cost analysis of the use of a new care pathway with a digital health platform for blood pressure telemonitoring for women at risk of preeclampsia.

STUDY DESIGN

This is a cost analysis of a case-control study with women with chronic hypertension, history of preeclampsia, maternal cardiac or kidney disease at intake of pregnancy. Antenatal care with a reduced visit schedule and a digital health platform (SAFE@HOME, n = 97) was compared to a retrospective control group (n = 133) with usual care without self-monitoring.

MAIN OUTCOME MEASURES

Costs per pregnancy (€) of healthcare consumption of antenatal clinic visits, ultrasound assessments, antenatal admissions, laboratory and other diagnostic tests, and societal costs such as traveling and work absence.

RESULTS

Baseline characteristics and perinatal outcomes were similar between both groups. A significant reduction of antenatal visits, ultrasounds and hypertension-related admissions was associated with use of the digital platform. In the SAFE@HOME group, costs of antenatal care, including the costs of the digital platform, were 19.7% lower compared to the control group (median €3616 [IQR 3071 - 5329] vs €4504 [IQR 3515-6923], p = 0.001). Total costs per pregnancy, including societal costs, were also reduced (€7485 [IQR 6338-10,173] vs €9150, [IQR 7546-12,286] p < 0.001). Each euro invested in the platform saved on average €8 of antenatal care resources.

CONCLUSION

The use of a digital platform for blood pressure and symptom monitoring in antenatal care for high-risk women is associated with lower costs compared to conventional care, while observed maternal and neonatal outcomes are similar.

Study protocol of a randomized, double-blind, placebo-controlled, multi-center trial to treat antipsychotic-induced weight gain: the Metformin-Lifestyle in antipsychotic users (MELIA) trial

BACKGROUND

Antipsychotic-induced Weight Gain (AiWG) is a debilitating and common adverse effect of antipsychotics. AiWG negatively impacts life expectancy, quality of life, treatment adherence, likelihood of developing type-2 diabetes and readmission. Treatment of AiWG is currently challenging, and there is no consensus on the optimal management strategy. In this study, we aim to evaluate the use of metformin for the treatment of AiWG by comparing metformin with placebo in those receiving treatment as usual, which includes a lifestyle intervention.

METHODS

In this randomized, double-blind, multicenter, placebo-controlled, pragmatic trial with a follow-up of 52 weeks, we aim to include 256 overweight participants (Body Mass Index (BMI) > 25 kg/m²) of at least 16 years of age. Patients are eligible if they have been diagnosed with schizophrenia spectrum disorder and if they have been using an antipsychotic for at least three months. Participants will be randomized with a 1:1 allocation to placebo or metformin, and will be treated for a total of 26 weeks. Metformin will be started at 500 mg b.i.d. and escalated to 1000 mg b.i.d. 2 weeks thereafter (up to a maximum of 2000 mg daily). In addition, all participants will undergo a lifestyle intervention as part of the usual treatment consisting of a combination of an exercise program and dietary consultations. The primary outcome measure is difference in body weight as a continuous trait between the two arms from treatment inception until 26 weeks of treatment, compared to baseline. Secondary outcome measures include: 1) Any element of metabolic syndrome (MetS); 2) Response, defined as ≥5% body weight loss at 26 weeks relative to treatment inception; 3) Quality of life; 4) General mental and physical health; and 5) Cost-effectiveness. Finally, we aim to assess whether genetic liability to BMI and MetS may help estimate the amount of weight reduction following initiation of metformin treatment.

DISCUSSION

The pragmatic design of the current trial allows for a comparison of the efficacy and safety of metformin in combination with a lifestyle intervention in the treatment of AiWG, facilitating the development of guidelines on the interventions for this major health problem.

TRIAL REGISTRATION

This trial was registered in the Netherlands Trial Register (NTR) at  https://www.trialregister.nl/trial/8440 as NTR NL8840 on March 8, 2020.

Case-studies of displacement effects in Dutch hospital care

BACKGROUND

Under a constrained health care budget, cost-increasing technologies may displace funds from existing health services. However, it is unknown what services are displaced and how such displacement takes place in practice. The aim of our study was to investigate how the Dutch hospital sector has dealt with the introduction of cost-increasing health technologies, and to present evidence of the relative importance of three main options to deal with cost-increases in health care: increased spending, increased efficiency, or displacement of other services.

METHODS

We conducted six case-studies and interviewed 84 professionals with various roles and responsibilities (practitioners, heads of clinical department, board of directors, insurers, and others) to investigate how they experienced decision making in response to the cost pressure of cost-increasing health technologies. Transcripts were analyzed thematically in Atlas.ti on the basis of an item list.

RESULTS

Direct displacement of high-value care due to the introduction of new technologies was not observed; respondents primarily pointed to increased spending and efficiency measures to accommodate the introduction of the cost-increasing technologies. Respondents found it difficult to identify the opportunity costs; partly due to limited transparency in the internal allocation of funds within a hospital. Furthermore, respondents experienced the entry of new technologies and cost-containment as two parallel processes that are generally not causally linked: cost containment was experienced as a permanent issue to level costs and revenues, independent from entry of new technologies. Furthermore, the way of financing was found important in displacement in the Netherlands, especially as there is a separate budget for expensive drugs. This budget pressure was found to be reallocated horizontally across departments, whereas the budget pressure of other services is primarily reallocated vertically within departments or divisions. Respondents noted that hospitals have reacted to budget pressures primarily through a narrowing in the portfolio of their services, and a range of (other) efficiency measures. The board of directors is central in these processes, insurers are involved only to a limited extent.

CONCLUSIONS

Our findings indicate that new technologies were generally accommodated by greater efficiency and increased spending, and that hospitals sought savings or efficiency measures in response to cumulative cost pressures rather than in response to single cost-increasing technologies.

MRI-guided pulmonary vein isolation for atrial fibrillation: what is good enough? An early health technology assessment

Next to anticoagulation, pulmonary vein isolation (PVI) is the most important interventional procedure in the treatment of atrial fibrillation (AF). Despite widespread clinical application of this therapy, patients often require multiple procedures to reach clinical success. In contrast to conventional imaging modalities, MRI allows direct visualisation of the ablation lesion. Therefore, the use of real-time MRI to guide cardiac electrophysiology procedures may increase clinical effectiveness. An essential aspect, from a decision-making point of view, is the effect on costs and the potential cost-effectiveness of new technologies. Generally, health technology assessment (HTA) studies are performed when innovations are close to clinical application. However, early stage HTA can inform users, researchers and funders about the ultimate clinical and economic potential of a future innovation. Ultimately, this can guide funding allocation. In this study, we performed an early HTA evaluate MRI-guided PVIs.

Methods

We performed an economic evaluation using a decision tree with a time-horizon of 1 year. We calculated the clinical effectiveness (defined as the proportion of patients that is long-term free of AF after a single procedure) required for MRI-guided PVI to be cost-effective compared with conventional treatment.

Results

Depending on the cost-effectiveness threshold (willingness to pay for one additional quality-of-life adjusted life year (QALY), interventional MRI (iMRI) guidance for PVI can be cost-effective if clinical effectiveness is 69.8% (at €80 000/QALY) and 77.1% (at €20 000/QALY), compared with 64% for fluoroscopy-guided procedures.

Conclusion

Using an early HTA, we established a clinical effectiveness threshold for interventional MRI-guided PVIs that can inform a clinical implementation strategy. If crucial technologies are developed, it seems plausible that iMRI-guided PVIs will be able to reach this threshold.

One-stop routing for surgical interventions: a cost-analysis of endoscopic groin repair

BACKGROUND

Single-visit (SV) totally extraperitoneal (TEP) inguinal hernia repair is an efficient service without impairment of safety or complication rate. Data on the economic impact of this approach are rare. The aim of this study was to compare the costs between the SV TEP and the regular TEP in an employed healthy population from a hospital and societal point of view.

METHODS

Retrospectively collected hospital costs and prospectively collected societal costs were obtained from patients treated between July 2016 and January 2018. Outcome measures consisted of all documented institutional care, productivity loss and medical consumption.

RESULTS

For analysing the hospital costs, a total of 116 SV patients were matched to 116 regular patients. The hospital costs of a mean SV patient were €1148.78 compared to €1242.84 for a regular patient, with a mean difference of €94.06. Prospective analyses of 50 SV patients and 50 regular patients demonstrated higher societal costs for a mean regular patient (€2188.33) compared to a mean SV patient (€1621.44). The mean total cost difference between a SV TEP repair and a regular TEP repair equalled €660.95 corresponding to a 19.3% decrease in costs.

CONCLUSIONS

This comprehensive cost-analysis showed that in an employed, healthy population, the SV TEP repair outprices the regular TEP repair, with savings of €660.95 per patient, reflecting a 19.3% decrease in costs. This routing is mainly interesting from a societal point of view as the difference is mainly impacted by a decrease in societal costs.

The effect of aerobic interval training and continuous training on exercise capacity and its determinants

Objective We aimed to investigate (1) the effects of aerobic interval training (AIT) and aerobic continuous training (ACT) on (sub)maximal exercise measures and its determinants including endothelial function, muscle strength and cardiac autonomic function, and (2) the relationship between exercise capacity and these determinants. Methods Two-hundred coronary artery disease (CAD) patients (58.4 ± 9.1 years) were randomized to AIT or ACT for 12 weeks. All patients performed a cardiopulmonary exercise test and endothelial function measurements before and after the intervention; a subpopulation underwent muscle strength and heart rate variability (HRV) assessments. Results The VO₂, heart rate and workload at peak and at first and second ventilatory threshold increased (P-time <0.001); the oxygen uptake efficiency slope (P-time <0.001) and half time of peak VO₂ (P-time <0.001) improved. Endothelial function and heart rate recovery (HRR) at 1 and 2 min improved (P-time <0.001), while measures of muscle strength and HRV did not change. Both interventions were equally effective. Significant correlations were found between baseline peak VO₂ and (1) quadriceps strength (r = 0.44; P < 0.001); (2) HRR at 2 min (r = 0.46; P < 0.001). Changes in peak VO₂ correlated significantly with changes in (1) FMD (ρ = 0.17; P < 0.05); (2) quadriceps strength (r = 0.23; P < 0.05); (3) HRR at 2 min (ρ = 0.18; P < 0.05) and Total power of HRV (ρ = 0.41; P < 0.05). Conclusions This multicentre trial shows equal improvements in maximal and submaximal exercise capacity, endothelial function and HRR after AIT and ACT, while these training methods seem to be insufficient to improve muscle strength and HRV. Changes in peak VO₂ were linked to changes in all underlying parameters.

Effects of aerobic interval training and continuous training on cellular markers of endothelial integrity in coronary artery disease: a SAINTEX-CAD substudy

In this large multicenter trial, we aimed to assess the effect of aerobic exercise training in stable coronary artery disease (CAD) patients on cellular markers of endothelial integrity and to examine their relation with improvement of endothelial function. Two-hundred CAD patients (left ventricular ejection fraction > 40%, 90% male, mean age 58.4 ± 9.1 yr) were randomized on a 1:1 base to a supervised 12-wk rehabilitation program of either aerobic interval training or aerobic continuous training on a bicycle. At baseline and after 12 wk, numbers of circulating CD34+/KDR+/CD45dim endothelial progenitor cells (EPCs), CD31+/CD3+/CXCR4+ angiogenic T cells, and CD31+/CD42b− endothelial microparticles (EMPs) were analyzed by flow cytometry. Endothelial function was assessed by flow-mediated dilation (FMD) of the brachial artery. After 12 wk of aerobic interval training or aerobic continuous training, numbers of circulating EPCs, angiogenic T cells, and EMPs were comparable with baseline levels. Whereas improvement in peak oxygen consumption was correlated to improvement in FMD (Pearson r = 0.17, P = 0.035), a direct correlation of baseline or posttraining EPCs, angiogenic T cells, and EMP levels with FMD was absent. Baseline EMPs related inversely to the magnitude of the increases in peak oxygen consumption (Spearman rho = −0.245, P = 0.027) and FMD (Spearman rho = −0.374, P = 0.001) following exercise training. In conclusion, endothelial function improvement in response to exercise training in patients with CAD did not relate to altered levels of EPCs and angiogenic T cells and/or a diminished shedding of EMPs into the circulation. EMP flow cytometry may be predictive of the increase in aerobic capacity and endothelial function.

Diet, exercise, and endothelial function in obese adolescents

BACKGROUND AND OBJECTIVES

Endothelial dysfunction is the first, although reversible, sign of atherosclerosis and is present in obese adolescents. The primary end point of this study was to investigate the influence of a multicomponent treatment on microvascular function. Additional objectives and end points were a reduced BMI SD score, improvements in body composition, exercise capacity, and cardiovascular risk factors, an increase in endothelial progenitor cells (EPCs), and a decrease in endothelial microparticles (EMPs).

METHODS

We used a quasi-randomized study with 2 cohorts of obese adolescents: an intervention group (n = 33; 15.4 ± 1.5 years, 24 girls and 9 boys) treated residentially with supervised diet and exercise and a usual care group (n = 28; 15.1 ± 1.2 years, 22 girls and 6 boys), treated ambulantly. Changes in body mass, body composition, cardiorespiratory fitness, microvascular endothelial function, and circulating EPCs and EMPs were evaluated after 5 months and at the end of the 10-month program.

RESULTS

Residential intervention decreased BMI and body fat percentage, whereas it increased exercise capacity (P < .001 after 5 and 10 months). Microvascular endothelial function also improved in the intervention group (P = .04 at 10 months; + 0.59 ± 0.20 compared with + 0.01 ± 0.12 arbitrary units). Furthermore, intervention produced a significant reduction in traditional cardiovascular risk factors, including high-sensitivity C-reactive protein (P = .012 at 10 months). EPCs were increased after 5 months (P = .01), and EMPs decreased after 10 months (P = .004).

CONCLUSIONS

A treatment regimen consisting of supervised diet and exercise training was effective in improving multiple adolescent obesity-related end points.

Aerobic interval training and continuous training equally improve aerobic exercise capacity in patients with coronary artery disease: the SAINTEX-CAD study

BACKGROUND

Exercise-based cardiac rehabilitation increases peak oxygen uptake (peak VO₂), which is an important predictor of mortality in cardiac patients. However, it remains unclear which exercise characteristics are most effective for improving peak VO₂ in coronary artery disease (CAD) patients. Proof of concept papers comparing Aerobic Interval Training (AIT) and Moderate Continuous Training (MCT) were conducted in small sample sizes and findings were inconsistent and heterogeneous. Therefore, we aimed to compare the effects of AIT and Aerobic Continuous Training (ACT) on peak VO₂, peripheral endothelial function, cardiovascular risk factors, quality of life and safety, in a large multicentre study.

METHODS

Two-hundred CAD patients (LVEF >40%, 90% men, mean age 58.4 ± 9.1 years) were randomized to a supervised 12-week cardiac rehabilitation programme of three weekly sessions of either AIT (90-95% of peak heart rate (HR)) or ACT (70-75% of peak HR) on a bicycle. Primary outcome was peak VO₂; secondary outcomes were peripheral endothelial function, cardiovascular risk factors, quality of life and safety.

RESULTS

Peak VO₂ (ml/kg/min) increased significantly in both groups (AIT 22.7 ± 17.6% versus ACT 20.3 ± 15.3%; p-time<0.001). In addition, flow-mediated dilation (AIT+34.1% (range -69.8 to 646%) versus ACT+7.14% (range -66.7 to 503%); p-time<0.001) quality of life and some other cardiovascular risk factors including resting diastolic blood pressure and HDL-C improved significantly after training. Improvements were equal for both training interventions.

CONCLUSIONS

Contrary to earlier smaller trials, we observed similar improvements in exercise capacity and peripheral endothelial function following AIT and ACT in a large population of CAD patients.

Endothelial progenitor cells and endothelial microparticles are independent predictors of endothelial function

OBJECTIVE

To examine the degree of microvascular endothelial dysfunction in relation to classical cardiovascular risk factors, arterial stiffness, and numbers of circulating endothelial progenitor cells (EPCs) and endothelial microparticles (EMPs), in obese and normal-weight children.

STUDY DESIGN

Cross-sectional study with 57 obese (15.2±1.4 years) and 30 normal-weight children (15.4±1.5 years). The principal outcome was microvascular endothelial function measured with peripheral arterial tonometry. Fasting blood samples were taken for biochemical analysis and EMPs (CD31+/CD42b- particles) and EPCs (CD34+/KDR+/CD45dim/- cells) flow cytometry. Characteristics between groups were compared by use of the appropriate independent samples test; a stepwise multiple regression analysis was used to determine independent predictors of microvascular endothelial function.

RESULTS

Microvascular endothelial function was significantly impaired in obese children and inversely correlated with body mass index Z scores (r=-0.249; P=.021) and systolic blood pressure (r=-0.307; P=.004). The number of EPCs was significantly lower in obese children and correlated with endothelial function (r=0.250; P=.022), and the number of EMPs was significantly greater in obese children and correlated inversely with endothelial function (r=-0.255; P=.021). Multivariate analysis revealed that systolic blood pressure and numbers of circulating EPCs and EMPs are important determinants of endothelial function.

CONCLUSION

Obese children demonstrate impaired endothelial microvascular function, increased arterial stiffness, fewer EPCs, and more EMPs. Besides systolic blood pressure, EPC and EMP counts independently predict the presence of microvascular endothelial dysfunction.

Long-term vascular responses to Resolute® and Xience V® polymer-based drug-eluting stents in a rabbit model of atherosclerosis

OBJECTIVES

To assess the late postinterventional response to iliac stenting in atheromatous rabbits using the Xience V everolimus-eluting stent (Xience V EES; Abbott Vascular) and the Resolute zotarolimus-eluting stent (Resolute ZES; Medtronic Vascular) with the MultiLink Vision bare metal stent (BMS; Abbott Vascular) as a reference.

BACKGROUND

Xience V EES and Resolute ZES were developed to overcome shortcomings of first-generation DES.

METHODS

Functional and microscopic changes were assessed by organ bath experiments and histopathologic examination. Gene expression was investigated using RT-PCR.

RESULTS

After 91 days, re-endothelialization was nearly complete (BMS: 93 ± 3%; Resolute ZES: 92 ± 2%; Xience V EES: 94 ± 3%; P = 0.10). Neointima thickness was similar in Resolute ZES (0.17 ± 0.08 mm) and BMS (0.17 ± 0.09 mm), and reduced in Xience V EES (0.03 ± 0.01 mm; P < 0.0001). Xience V EES had less peri-strut inflammation compared with BMS (P = 0.001) and Resolute ZES (P = 0.0001), while arterial segments distal to Xience V EES were more sensitive to acetylcholine than those distal to BMS and Resolute ZES (P = 0.02). Lectin-like oxidized receptor-1 was overexpressed in stented arteries (P < 0.001), whereas thrombomodulin was downregulated in Resolute ZES (P = 0.01) and BMS (P = 0.02) compared to unstented arteries of rabbits on regular chow. No significant changes were seen for vascular cell adhesion molecule-1, nitric oxide synthase 3, or endothelin-1.

CONCLUSIONS

At 3-month follow-up, nearly complete re-endothelialization was achieved for all stent groups. Xience V EES induced greater suppression of neointimal growth and peri-strut inflammation, higher vasorelaxation to acetylcholine, and expression of thrombomodulin at the level of unstented controls.

Exercise acutely reverses dysfunction of circulating angiogenic cells in chronic heart failure

AIMS

Recruitment of endothelial progenitor cells (EPCs) and enhanced activity of circulating angiogenic cells (CACs) might explain the benefits of exercise training in reversing endothelial dysfunction in chronic heart failure (CHF) patients. We studied baseline EPC numbers and CAC function and the effect of a single exercise bout.

METHODS AND RESULTS

Forty-one CHF patients (mild, n = 22; severe, n = 19) and 13 healthy subjects were included. Migratory activity of CACs was evaluated in vitro and circulating CD34+ and CD34+/KDR+ (EPC) cells were quantified by flow cytometry before and after cardiopulmonary exercise testing (CPET). Circulating stromal cell-derived factor-1alpha (SDF-1alpha) and vascular endothelial growth factor (VEGF) concentrations were measured. Both CAC migration as well as CD34+ cell numbers were significantly reduced in CHF, whereas CD34+/KDR+ cells were not different from controls. Endothelial dysfunction was related to impaired CAC migration (r = 0.318, P = 0.023). Cardiopulmonary exercise testing improved CAC migration in severe (+52%, P < 0.005) and mild CHF (+31%, P < 0.005), restoring it to levels similar to controls. Following CPET, SDF-1alpha increased in healthy controls and mild CHF (P < 0.005). Vascular endothelial growth factor, CD34+, and CD34+/KDR+ cell numbers remained unchanged.

CONCLUSION

The present findings reveal a potent stimulus of acute exercise to reverse CAC dysfunction in CHF patients with endothelial dysfunction.