Atrial tachycardia with widely-split P waves may mimic a distinct faster atrial tachycardia with half the cycle length of the actual P-P interval.
A 57-year-old man with atrial tachycardia (AT) after cavo-tricuspid isthmus ablation underwent electrophysiological testing. Mapping revealed atrial activation with a cycle length exactly twice that of the P-P interval on electrocardiogram. Electroanatomic mapping revealed an AT focus near the left superior pulmonary vein, with inter-atrial conduction occurring in the lower septum and cavo-tricuspid isthmus conduction block. A propagation map demonstrated activation going down the left atrial posterior wall and right atrial free wall, generating different positive P waves in the inferior leads. The focal AT with inter- and intra-atrial conduction block exhibited widely-split P waves misinterpreted as a distinct AT.
Yamada
Takumi
T
Division of Cardiovascular Disease, University of Alabama at Birmingham, Birmingham, AL 35294-0019, USA. takumi-y@fb4.so-net.ne.jp
Doppalapudi
Harish
H
McElderry
H Thomas
HT
Kay
G Neal
GN
D000200:Action Potentials; D016275:Atrial Function; D018780:Body Surface Potential Mapping; D017115:Catheter Ablation; D003951:Diagnostic Errors; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D006329:Heart Conduction System / Q000503:physiopathology* / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D013617:Tachycardia, Supraventricular / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery; D013997:Time Factors