OBJECTIVE: To estimate the long-term economic and health impact of managing bradycardia due to sinoatrial node disease or atrioventricular block with a dual (DDD or DDDR) vs. single chamber ventricular pacemaker (VVI or VVIR). METHODS: A discrete event simulation was constructed to evaluate the outcomes over five years. During the simulation, each patient may develop post-operative complications, severe pacemaker syndrome leading to replacement of the VVI(R) with DDD(R), atrial fibrillation (which may become chronic and require anticoagulants), or have a stroke. A time for each event is sampled from the distribution of failure times specified by the individual's risk profile. Life expectancy was estimated and assumed the same with either device. Model risk functions are based on long-term randomized trials (Canadian Trial of Physiological Pacing and Mode Selection Trial in Sinus-Node Dysfunction). Probabilistic sensitivity analyses were performed for key input parameters. Direct medical costs are reported in 2004 Euros (€). Benefits and costs are discounted at 3% per year. RESULTS: Chronic atrial fibrillation was estimated to be 24% lower with DDD(R). Discounted costs over 5 years were about €10,000 per patient in either cohort, mean net additional cost of €106 with DDD(R). DDD(R) led to 0.09 additional QALY; a mean cost-effectiveness ratio of €1,177/QALY, with 21% of replications indicating dominance for DDD(R). Severe pacemaker syndrome requiring switch to DDD(R) occurred in 16.8% with VVI(R); the results are sensitive to the proportion that would seek replacement. CONCLUSION: Lower initial costs with VVI(R) were offset by second operations to switch to DDD(R) and costs of atrial fibrillation. Thus, dual chamber pacemakers are economically attractive in management of patients with bradycardia.