Aims Paroxysmal atrial fibrillation (PAF) is common, often silent, and can be difficult to detect. Echocardiographic parameters assessing left atrial (LA) remodelling correlated with atrial fibrosis in permanent AF, but less is known about earlier stages such as PAF. We aimed to evaluate whether 2D and 3D echocardiographic (2DE and 3DE) assessment of LA anatomy and function is able to identify patients with PAF.Methods and results This case control study included 102 patients without overt heart disease, 44 patients with PAF. Anatomical remodelling was assessed using indexed maximal, minimal, and preatrial contraction volumes. Reservoir, conduit, and pump functions were assessed by volume and strain methods. All parameters were assessed by 2DE and 3DE and were compared between the two groups. Receiver-operating characteristic curves were constructed for each parameter for PAF prediction. PAF patients had bigger LA volumes than non-PAF group. Using 3DE, all atrial functions were impaired in the PAF group, regardless of the parameters used (all P < 0.05), whereas using 2DE, conduit function did not reach significant difference. Areas under the curve (AUCs) for 3D parameters were higher than those for equivalent 2DE parameters. PAF was best predicted by LA minimal indexed volume assessed by 2DE or 3DE (AUC 0.82 and 0.86, respectively) and 3D-LA ejection fraction and area strain (AUC = 0.82 and 0.81, respectively).Conclusion Anatomical and functional LA remodelling assessed by 2DE and 3DE is independently and strongly associated with PAF, suggesting that these parameters can help identify PAF.