Clegg A J, Scott D A, Loveman E, Colquitt J, Hutchinson J, Royle P, Bryant J
Southampton Health Technology Assessments Centre, Wessex Institute for Health Research and Development, University of Southampton, UK.
Health Technol Assess. 2005 Nov;9(45):1-132, iii-iv. doi: 10.3310/hta9450.
To assess the clinical and cost-effectiveness of left ventricular assist devices (LVADs) as a bridge to heart transplantation (BTT), as a bridge to myocardial recovery (BTR) or as a long-term chronic support (LTCS) for people with end-stage heart failure (ESHF).
For the systematic review, electronic databases and bibliographies of related publications plus experts and manufacturers. For the economic evaluations, data originated from the systematic review of clinical and cost-effectiveness, UK hospitals, device manufacturers and expert opinion.
For the systematic review, studies were selected and assessed against a set of rigorous criteria; data were then synthesised using a narrative approach through subgroup analysis based on the indication for treatment, type of LVAD and quality of studies. The economic evaluation developed two models to evaluate the use of LVADs, first as a BTT and second as LTCS for patients suffering from ESHF.
Sixteen studies assessed the clinical effectiveness of LVADs as a BTT. Despite the poor methodological quality of the evidence, LVADs appeared beneficial compared to other treatment options (i.e. inotropic agents or usual care) or to no care (i.e. the natural history of ESHF) improving the survival of people with ESHF during the period of support and following heart transplantation. Patients supported by an LVAD appeared to have an improved functional status compared with those on usual care and experienced an improvement in their quality of life from before device implantation to the period during support. Serious adverse events are a risk for patients with an LVAD. With a scarcity of evidence directly comparing different devices, it is difficult to identify specific devices as the most clinically effective. The HeartMate LVAD is the only device that has evidence comparing it with the different alternatives, appearing to be more clinically effective than inotropic agents and usual care and as clinically effective as the Novacor device. Second generation devices, such as Jarvik 2000 and MicroMed Debakey LVADs, are early in their development but show considerable promise that should be assessed through long-term studies. Evidence of the clinical effectiveness of LVADs as a BTR was limited to seven non-comparative observational studies that appeared to show that the LVADs were beneficial in providing support until myocardial recovery. It was not possible to assess whether the LVADs are more effective than other alternatives or specific devices. No evidence was found on the quality of life or functional status of patients and limited information on adverse events was reported. Six studies assessed the clinical effectiveness of LVADs as an LTCS and from these it was evident that LVADs provided benefits in terms of improved survival, functional status and quality of life. Nineteen studies assessed the costs and cost-effectiveness of LVADS for people with ESHF, with the majority being simple costing studies and very few studies of the cost-effectiveness of LVADs. With no relevant cost-effectiveness studies available, an economic evaluation for BTT and LTCS was developed. The economic evaluation has shown that neither LVAD indication considered, that is, BTT and LTCS, is a cost-effective use. For the HeartMate LVAD used as a BTT the cost per QALY was pound 65,242. In the less restrictive indication, LTCS, where LVADs are not just given to patients awaiting transplantation, the analysis has shown that LTCS is not cost-effective. The baseline cost per QALY of the first-generation HeartMate LVAD was pound 170,616. One- and multi-way sensitivity analysis had limited effect on the cost per QALY. A hypothetical scenario based on the cost of a second-generation MicroMed DeBakey device illustrated that a 60% improvement in survival over first-generation devices was necessary before the incremental cost-effectiveness approached pound 40,000 per QALY.
Although the review showed that LVADs are clinically effective as a BTT with ESHF, the economic evaluation indicated that they are not cost-effective. With the limited and declining availability of donor hearts for transplantation, it appears that the future of the technology is in its use as an LTCS. Further research is needed to examine the clinical effectiveness of LVADs for people with ESHF, assessing patient survival, functional ability, quality of life and adverse events. Evaluations of the clinical effectiveness of LVADs should include economic evaluations, as well as data on quality of life, utilities, resources and costs. A systematic review of the epidemiology of ESHF should be undertaken to assess its potential impact.
评估左心室辅助装置(LVAD)作为终末期心力衰竭(ESHF)患者心脏移植(BTT)的桥梁、心肌恢复(BTR)的桥梁或长期慢性支持(LTCS)的临床效果和成本效益。
对于系统评价,电子数据库、相关出版物的参考文献以及专家和制造商。对于经济评估,数据来源于临床和成本效益的系统评价、英国医院、设备制造商和专家意见。
对于系统评价,根据一系列严格标准选择和评估研究;然后通过基于治疗指征、LVAD类型和研究质量的亚组分析,采用叙述性方法综合数据。经济评估开发了两个模型来评估LVAD的使用,第一个是作为BTT,第二个是作为ESHF患者的LTCS。
16项研究评估了LVAD作为BTT的临床效果。尽管证据的方法学质量较差,但与其他治疗选择(即强心剂或常规治疗)或不治疗(即ESHF的自然病程)相比,LVAD似乎有益,可提高ESHF患者在支持期间和心脏移植后的生存率。与接受常规治疗的患者相比,接受LVAD支持的患者功能状态似乎有所改善,并且从装置植入前到支持期间生活质量有所提高。严重不良事件是LVAD患者面临的风险。由于直接比较不同装置的证据稀缺,难以确定哪种特定装置在临床上最有效。HeartMate LVAD是唯一有证据将其与不同替代方案进行比较的装置,似乎比强心剂和常规治疗在临床上更有效,与Novacor装置临床效果相当。第二代装置,如Jarvik 2000和MicroMed Debakey LVAD,尚处于早期开发阶段,但显示出相当大的前景,应通过长期研究进行评估。LVAD作为BTR的临床效果证据仅限于7项非对照观察性研究,这些研究似乎表明LVAD在提供支持直至心肌恢复方面有益。无法评估LVAD是否比其他替代方案或特定装置更有效。未发现关于患者生活质量或功能状态的证据,报告的不良事件信息有限。6项研究评估了LVAD作为LTCS的临床效果,从中可以明显看出LVAD在提高生存率、功能状态和生活质量方面具有益处。19项研究评估了ESHF患者使用LVAD的成本和成本效益,大多数是简单的成本核算研究,很少有LVAD成本效益研究。由于没有可用的相关成本效益研究,因此针对BTT和LTCS进行了经济评估。经济评估表明,所考虑的两种LVAD适应证,即BTT和LTCS,都不是具有成本效益的使用方式。对于用作BTT的HeartMate LVAD,每获得一个质量调整生命年(QALY)的成本为65,242英镑。在限制较少的适应证LTCS中,LVAD不仅给予等待移植的患者,分析表明LTCS不具有成本效益。第一代HeartMate LVAD的每QALY基线成本为170,616英镑。单向和多向敏感性分析对每QALY成本的影响有限。基于第二代MicroMed DeBakey装置成本的假设情景表明,在增量成本效益接近每QALY 40,000英镑之前,生存率需要比第一代装置提高60%。
尽管综述表明LVAD作为ESHF患者的BTT在临床上有效,但经济评估表明它们不具有成本效益。由于可用于移植的供体心脏数量有限且不断减少,该技术的未来似乎在于其作为LTCS的应用。需要进一步研究以检查LVAD对ESHF患者的临床效果,评估患者生存率、功能能力、生活质量和不良事件。LVAD临床效果评估应包括经济评估以及生活质量、效用、资源和成本数据。应进行ESHF流行病学的系统评价以评估其潜在影响。