Pseudoblock of the Posterior Mitral Line and Perimitral Tachycardias

This paper sought to look at the standard criteria for mitral line block with endocardial and epicardial activation mapping. The study authors included 56 patients in whom posterior mitral line via radiofrequency ablation was performed. Results were compared with high-resolution activation mapping of the endocardium and epicardium. Mitral block was achieved in 91% of patients. Residual endocardial (27.2%) or epicardial (72.7%) connections were demonstrated using activation mapping. IN addition, mitral line block was achieved in 75% of patients by targeting insertion sites. The authors concluded that “standard criteria for posterior mitral line block may not distinguish block from pseudoblock.”


Barkagan M, et al. Circ Arrhyth Electrophysiol. 2019;doi:10.1161/CIRCEP.118.006933