Next to anticoagulation, pulmonary vein isolation (PVI) is the most important interventional procedure in the treatment of atrial fibrillation (AF). Despite widespread clinical application of this therapy, patients often require multiple procedures to reach clinical success. In contrast to conventional imaging modalities, MRI allows direct visualisation of the ablation lesion. Therefore, the use of real-time MRI to guide cardiac electrophysiology procedures may increase clinical effectiveness. An essential aspect, from a decision-making point of view, is the effect on costs and the potential cost-effectiveness of new technologies. Generally, health technology assessment (HTA) studies are performed when innovations are close to clinical application. However, early stage HTA can inform users, researchers and funders about the ultimate clinical and economic potential of a future innovation. Ultimately, this can guide funding allocation. In this study, we performed an early HTA evaluate MRI-guided PVIs.MethodsWe performed an economic evaluation using a decision tree with a time-horizon of 1 year. We calculated the clinical effectiveness (defined as the proportion of patients that is long-term free of AF after a single procedure) required for MRI-guided PVI to be cost-effective compared with conventional treatment.ResultsDepending on the cost-effectiveness threshold (willingness to pay for one additional quality-of-life adjusted life year (QALY), interventional MRI (iMRI) guidance for PVI can be cost-effective if clinical effectiveness is 69.8% (at €80 000/QALY) and 77.1% (at €20 000/QALY), compared with 64% for fluoroscopy-guided procedures.ConclusionUsing an early HTA, we established a clinical effectiveness threshold for interventional MRI-guided PVIs that can inform a clinical implementation strategy. If crucial technologies are developed, it seems plausible that iMRI-guided PVIs will be able to reach this threshold.