Introduction: Primary angioplasty (PTCA) or intravenous thrombolysis are the recommended treatment of acute myocardial infarction. According to results of clinical investigations however primary PTCA provides a more favourable short-term as well as long-term prognosis. As this method is much more expensive we were interested in its cost-effectiveness as compared with cheaper intravenous thrombolysis.
Methods: We constructed an decision analysis model (programme DATA 3.5, TreeAge Software) to compare the strategy of primary PTCA and intravenous thrombolysis in acute myocardial infarction. Probabilities of clinical outcomes were obtained from a long-term randomized clinical trial (Zijlstra et al. NEJM, 1999). The relative risk of death in PTCA was 0.54, rehospitalization 0.52 and reinfarction 0.27. The costs of PTCA (100,000,- crowns), of streptokinase thrombolysis (4000,- crowns) and hospitalization (2820,- crowns) were estimated from costs of the catheterization laboratory and information obtained from health insurance companies. We assumed that the subsequent costs of treatment and quality of life after the first infarction were the same in both strategies. In patients with reinfarction we anticipated a reduced quality of life (coefficient of life quality 0.9). The average effect of treatment and costs of both strategies were evaluated in the course of five years. As an acceptable cost-effectiveness (ratio of difference in costs and effect) we considered costs up to 200,000,- crowns per one gained year of life.
Results: In the basic analysis we revealed that after 5 years the strategy of primary PTCA is more expensive (125,000,- crowns vs. 4500,- crowns) but has a greater effect, i.e. a longer life span (4.38 vs. 3.81) adjusted to quality of life). The cost-effectiveness (ratio of difference in costs and effect) expressing the costs of one gained year of life when using primary PTCA as compared with thrombolysis was despite the high cost of PTCA acceptable and amounted to 140,350,- crowns. Analysis of the sensitivity of the model confirmed the stability of favourable cost-effectiveness within a wide range of costs and therapeutic effect.
Conclusion: Primary PTCA is in acute myocardial infarction a cost-effective strategy) providing effect for an acceptable cost) despite the markedly higher costs of the procedure.