Post-introduction observation of transcatheter aortic valve implantation in Galicia (Spain)

HEALTH TECHNOLOGY ASSESSMENTS REPORTING COST-EFFECTIVENESS OF TRANSCATHETER AORTIC VALVE IMPLANTATION

Objectives: Made available since 2002, transcatheter aortic valve implantation (TAVI) is a minimally invasive new intervention which can provide significant survival improvement to patients with aortic stenosis. However, TAVI is expensive and currently not reimbursed by many governments. Some governments and institutions have been conducting health technology assessments (HTAs) to inform their reimbursement decisions. The aim of the present study is to review HTAs that have relied on a cost-effectiveness analysis to inform reimbursement decisions of TAVI.

Methods: A systematic literature review was conducted among published literature as well as reports released by HTA agencies. Predetermined inclusion and exclusion criteria, following the Preferred Reporting System for Systematic Reviews and Meta-Analysis guidelines, were used to select relevant HTAs. The selected papers were assessed against the Consolidated Health Economic Evaluation Reporting Standards.

Results: HTAs on TAVI from three countries were available for this review: Canada, Belgium, and the United Kingdom. All three HTAs used the Placement of Aortic Transcatheter Valve (PARTNER) trial data with Markov models to estimate the incremental cost effectiveness ratio. The three HTAs recommended conditional reimbursement for TAVI for otherwise inoperable patients. The HTAs did not use clear methods to estimate the health-related utility which ultimately affected their cost-effectiveness results. The UK HTA showed the best value for money (US$20,416 per quality-adjusted life-year).

Conclusion: All studies found TAVI to be more costly and less effective for high-risk patients suitable for surgery, whereas TAVI was consistently found to be cost effective for otherwise inoperable patients.

In vitro study of coronary flow occlusion in transcatheter aortic valve implantation

BACKGROUND

Transcatheter aortic valve implantation (TAVI) has been developed recently for patients with high morbidities and who are believed to be not tolerate standard surgical aortic valve replacement. Nevertheless, the TAVI is associated with complications such as potential obstruction of coronary ostia, mitral valve insufficiency, and stent migration although it seems promising. Impairment of the coronary blood flow after TAVI is catastrophic and it was believed to be associated with the close position of the coronary orifice and the aortic leaflets and valve stent. However, few data was available as to the anatomic relationship between valve stent and aortic root anatomic structures including the coronary arterial ostia, aortic leaflets.

METHODS

The aortic roots were observed in 40 hearts specimens. The width of aortic leaflet, height of aortic sinus annulus to the sinutubular junction (STJ), distance between aortic sinus annulus to its corresponding coronary ostia, and coronary arterial ostia to its corresponding STJ level were measured. Moreover, the relationships of valve stent, aortic leaflets and coronary ostia before/post stent implantation and after the open of aorta were evaluated respectively.

RESULTS

Approximate three quarters of the coronary ostia were located below the STJ level. The mean distances from left, right and posterior aortic sinus annulus to the related STJ level was comparable, which was 18.5±2.7, 18.9±2.6, 18.7±2.6 mm, respectively. Meanwhile, the height of left and right aortic sinus annulus to its corresponding coronary ostia was 16.6±2.8 and 17.2±3.1 mm for left and right side respectively.

CONCLUSIONS

Most of the coronary ostia were located below the STJ level and could be covered by the leaflets. This highlights the need of modified stents to prevent occlusion of coronary flow after TAVI.