OBJECTIVES: This paper aims at discussing hospital managers’ consideration of costs vs. tariffs (i.e. DRGs) when decisions on technological innovation have to be taken. To reach this goal, the paper takes a case-study approach, i.e. surgical ablation (SA) performed in concomitance with cardiac surgery procedures. METHODS: An observational, retrospective, multi-centre study was carried out. Three hospitals were selected based upon the volume of activity (i.e. >50 SA procedures/year). Patients (N=311) were enrolled during a 16-month period and recruited if they met inclusion criteria. Health care resource consumption was measured in detail through a bottom-up micro-costing approach. RESULTS: Direct and full costs of SA and of the concomitant cardiac surgery procedures were calculated per patient by using a standard costing approach.  Mean direct cost of surgical interventions (SA and the concomitant procedures) is €9,093 (range: 6,406- 14,746). While there is a large homogeneity among centres as to costs of SA (mean €1,889), significant differences (p<0.05) emerge in costs of concomitant interventions (mean €7,204) mainly because of different organisational patterns. CONCLUSIONS: Hospital managers are struggling to face the tension between scarcity of resources and increasing health care needs. Technological innovation opens new opportunities for hospital activities and patients’ health that however need to be assessed against its costs. Which cost (i.e. direct vs. full costing) is to be considered in the decision-making process however is still not clear. There is a tendency to consider full costing of new procedures and to decide whether they are financially sustainable by contrasting it to the relevant DRG(s). Nevertheless, it is here argued that firstly, direct costing better illustrates the true economic value of the innovative procedures and therefore should be primarily used, and secondly, financial hospital sustainability would need to be assessed based upon hospitals’ case-mix and not in silos.