AIMS: This study sought to investigate electrocardiographic characteristics, electrophysiological features, and radiofrequency ablation in @entity1 with focal @entity591 ( @entity591 ) originating from the septal mitral annulus. METHODS AND RESULTS: In 13 @entity1 with @entity591 originating from the septal mitral annulus, activation mapping was performed to identify the earliest activation site. Successful ablation was performed through either a transseptal (n = 12) or a retrograde aortic approach (n = 1). As confirmed by electrogram recordings, fluoroscopy, and three-dimensional (3D) mapping, successful ablation sites were located in the anterior paraseptal, mid- to anteroseptal, and posterior septal mitral annulus in eight, three, and two @entity1 , respectively. Foci for all locations demonstrated a negative/positive appearance in lead V1. Mapping in the right atrium demonstrated that the earliest right atrial activation was near the septum (His-bundle region or proximal coronary sinus). The electrograms at the successful ablation sites were fractionated in 9 @entity1 , and presented with an atrial:ventricular ratio of <1 in all 13 @entity1 . There were no complications in any @entity1 and long-term success was achieved in 12 of 13 @entity1 during the 23    6 months following ablation. CONCLUSION: The area surrounding the septal mitral annulus, most commonly the anterior paraseptal, is an unusual, but important site of origin for focal @entity591 , which is associated with a distinctive P-wave morphology and atrial endocardial activation sequence. Radiofrequency ablation of @entity591 originating from the septal mitral annulus, through either a transseptal or a retrograde aortic approach appears to be safe and effective.

Focal XXXX originating from the septal mitral annulus: electrocardiographic and electrophysiological characteristics and radiofrequency ablation.

@entity1 :: ('9606', 'Species') :: ['patients'] @entity591 :: ('MESH:D013610', 'Disease') :: ['AT', 'atrial tachycardia']
@entity591 :: (MESH:D013610,Disease) :: ['atrial tachycardia']
