Analisi di impatto sul budget di WatchmanTM, dispositivo per la prevenzione tromboembolica nei pazienti con fibrillazione atriale

Atrial fibrillation (AF) is a chronically progressing arrhythmia and an independent risk factor for stroke, leading to a five-fold increased risk of stroke. The available options for stroke prophylaxis are anticoagulant oral drugs, which include warfarin, used in stroke for several decades, the new generation of anticoagulant drugs (Xa inhibitors and direct thrombin inhibitors), anti-platelet drugs, generally recommended for patients in whom anticoagulants are contra-indicated, and left atrial appendage closure technologies implanted via a catheter-based delivery system, including WatchmanTM. The objective of this research is to estimate the 5-year budget impact for the Italian hospitals funded by the Italian National Health Service adopting WatchmanTM, comparing two scenarios: Scenario A, without the device, and Scenario B, with the device. A Budget Impact Model has been designed adopting a cohort approach, i.e. considering the whole eligible population and assessing the net impact of WatchmanTM (Scenario B versus Scenario A) on health care expenditure. The model has been populated with the relevant data, including the eligible population, the present and future prescribing mix—according to a clinical panel—the cost of the procedure, the cost of pharmacological therapies, follow-up costs, and the effects of thromboembolism and ictus. The eligible population is represented by patients with non-valvular atrial fibrillation, who are less than 85 years old and with a CHADS2 score ≥1. The budget impact has been firstly estimated for a sub-population of patients with atrial fibrillation, i.e. patients contraindicated or intolerant for chronic anticoagulant therapy. In fact, both the European and Italian Guidelines on atrial fibrillation management strongly support the use of left atrial occlusion in those patients who cannot be treated with this class of drugs. Then, the budget impact analysis has been performed for the overall eligible population of patients with atrial fibrillation. In the base-case, where data from clinical trials were used, if patients with high thromboembolic risk and contraindications to the use of long-term oral anticoagulant therapy are considered, the device would imply 145 million Euro savings in 5 years compared to treatment with antiplatelet drugs. A break-even point, when the cumulative costs of Scenario A (without the device) outbalance costs of Scenario B (with the device), is reached at the fifth year. The 5-year cumulative cost for Scenario A is over 3.1 billion Euros, while the same cost for Scenario B is under 3.0 billion Euros. When all eligible patients are included in the model, Scenario B (with WatchmanTM) would imply an additional cumulative cost of 95 million Euros in 5 years. The break-even point is reached at the seventh year, with the 5-year cumulative cost for Scenario A over the period close to 6.0 billion Euros, while for Scenario B this cost approximates 6.1 billion Euros. Using preliminary and more favourable data on the post-marketing risk-benefit profile of WatchmanTM, additional costs before the break-even point and savings after the break-even are, respectively, lower and higher than in the base-case. The budget impact analysis should be integrated with a cost-effectiveness analysis, to make decisions based on both value for money and long-term sustainability. Cost-effectiveness would incorporate the circumstance that WatchmanTM shows, if evidence from single trials is considered, a better profile with regard to overall mortality. A recent study shows that the Left Atrial Appendage (LAA) closure technology has, in comparison with warfarin, a lower cost per QALY than dabigatran versus warfarin.