Selection of aortic valve replacement versus transcatheter aortic valve replacement in high-risk patients: a Markov model

Transcription

1 Selection of aortic valve replacement versus transcatheter aortic valve replacement in high-risk patients: a Markov model Hemal Gada, MD, MBA and Thomas H Marwick, MD, PhD Department of Cardiovascular Medicine Cleveland Clinic Cleveland, OH, USA August 30, 2011 The presenters have no disclosures.

2 Background Transcatheter aortic valve replacement (TAVR) has transformed management of severe AS in candidates of unacceptable risk for AVR The application of TAVR will expand into situations of high (but not prohibitive) clinical risk To date, there has not been significant consideration of cost related to TAVR versus AVR

3 Objective We sought to compare the relative costeffectiveness of TAVR and AVR in high-risk surgical candidates using a decision-analytic model

4 Methods Model Development We used a Markov model with Monte Carlo simulations to study a hypothetical cohort of 10,000 patients through a number of health states that arose as consequence of undergoing TAVR versus AVR The simulation was initiated at age 80 Cycle length was 1 year We assessed incremental cost-effectiveness ratio (ICER) using: Lifetime cost of both interventions Quality-adjusted life years (QALY)

5 Methods Markov Model Severe Aortic Stenosis Screened for TAVR AVR and peri-procedural risks Stroke Heart Failure Post-AVR or TAVR Complications TAVR and peri-procedural risks Dead

6 Methods Model Development Society of Thoracic Surgeons (STS) score and European System for Cardiac Operative Risk Evaluation (EuroSCORE) were used to determine comparable groups of patients We informed the model using the limited data available in the literature 5 post-marketing transfemoral Edwards-Sapien registries or studies 5 studies that have evaluated outcomes in patients with high STS score and/or logistic EuroSCORE receiving tissue AVR

7 Methods States and Transitions AVR TAVR Peri-operative events Death 9.13±3.73% 5.84±3.19% TAVR Access Site Complications N/A 21.15±8.36% Stroke Peri-operative 3.74±1.00% 3.70±1.64% Follow-up events Death 22.47±5.93% 22.23±4.41% Heart Failure 11.3% Stroke Post-operative 2.1±0.7% 7.83±1.98% Post-AVR/TAVR Complications 4.8±0.7% Reoperation 0.24% 1.15±1.25% Complication mortality TAVR Access Site Complications N/A 11.8% Post-AVR/TAVR Complications 25.89% Stroke Peri-operative 11±2%

8 Methods - Costs Mean Cost ($/yr;±se) Heart failure Yearly costs after diagnosis: $10,832 Stroke $14,155±453 (acute treatment) Annual follow-up costs: $14,561±14,690 TAVR $49,106±1283 Cost of additional work-up: $374±500 Annual follow-up costs: $336 AVR $49,106±1283 Annual follow-up costs: $99 1 st 5 years Annual follow-up costs: $336 thereafter TAVR Access Site Complications Post-AVR/TAVR Complications $3,392±1000 Yearly costs: $300

9 Methods Utilities Condition Utility Value Heart failure 0.67±0.01 Stroke 0.455±0.01 Post-AVR 0.69 Post-TAVR 0.62±0.31 TAVR Access Site Complications -1 QAL week Post-AVR/TAVR Complications 0.67±0.01

10 Results AVR Cost ($) AVR QALYs TAVR Cost ($) TAVR QALYs ICER ($/QALY) Reference Case (50% suitability for TAVR) 10% suitability for TAVR 100% suitability for TAVR PARTNER A Scenario Analysis 20, , ,958 20, , ,640 20, , ,914 21, , ,792

11 Incremental Cost ($) Results Monte Carlo Analysis Incremental Cost-Effectiveness Plane Slope = $100K/QALY 50% 2.4% Incremental Effectiveness (QALYs)

12 Results Variables that make the most impact Probability Death AVR: 0 to 0.40 Probability Death TAVR: 0 to 0.40 Probability Early Death AVR: 0 to 0.20 Probability Stroke AVR: 0 to 0.15 Probability Stroke TAVR: 0 to 0.15 Probability Early Death TAVR: 0 to 0.20 Probability Early Stroke AVR: 0 to 0.10 Probability Early Stroke TAVR: 0 to 0.10 QALYs

13 Probability of Early Death TAVR Sensitivity Analysis Peri-operative death (AVR vs TAVR) AVR TAVR Probability of Early Death AVR

14 QALYs QALYs Sensitivity Analysis Annual probability of stroke post-tavr AVR TAVR AVR TAVR Probability Stroke TAVR Probability Stroke TAVR

15 Key Assumptions and Limitations Incorporation of retrospective and prospective, registry and trial data may meld risks of patients with different risk profiles Impact of post-avr complications is oversimplified Long-term stroke and heart failure mortality is assumed that of the post-avr/tavr population Unknown contribution of significant comorbidities to model outcome Analysis takes into account only costs reimbursed to the healthcare provider, not costs to the payor

16 Conclusion TAVR may provide net health benefits at acceptable cost in selected high-risk patients among whom AVR is the current procedure of choice

17

18 Backup Slides

19 Survival Results Monte Carlo Analysis Comparative Survival 1 0,9 0,8 0,7 0,6 0,5 0,4 0,3 TAVR AVR 0,2 0, Time (years)

20 Methods Model Development There are 5 post-marketing Edwards-Sapien registries or studies, only one of which is a randomized-controlled trial PARTNER (Cohort A and B) PARTNER-EU SOURCE Multicenter Canadian Milan Experience There are 5 studies that have evaluated outcomes in patients with high STS score and/or logistic EuroSCORE receiving tissue AVR Grossi et al; Ann Thorac Surg 2008;85:102-7 Kalavrouziotis et al; JCTS 2009;4:1-8 Lontyev et al; Ann Thorac Surg 2009;87: Thourani et al; Ann Thorac Surg 2011;91:49-55 PARTNER (Cohort A)