Atrial fibrillation originating from persistent left superior vena cava.
BACKGROUND
The left superior vena cava (LSVC) is the embryological precursor of the ligament of Marshall, which has been implicated in the initiation and maintenance of atrial fibrillation (AF). Rarely, the LSVC may persist and has been associated with some organized arrhythmias, though not with AF. We report 5 patients in whom the LSVC was a source of ectopy, initiating AF.


RESULTS
In 5 patients (4 men; age, 46+/-11 years) with symptomatic drug-refractory AF, ectopy from the LSVC resulting in AF was observed after pulmonary vein isolation. The ectopics were spontaneous in 2 and induced by isoproterenol in the others and preceded P-wave onset by 67+/-13 ms. During multielectrode or electroanatomic mapping, venous potentials were recorded circumferentially at the proximal LSVC near its junction with the coronary sinus (CS), but at the mid-LSVC level, they were recorded only on part of the circumference. The LSVC was electrically connected to the lateral left atrium (LA) and through the CS to the right atrium, with 4.1+/-2.3 CS-LSVC and 1.6+/-0.5 LA-LSVC connections per patient. Catheter ablation in the LSVC targeting these connections resulted in electrical isolation in 4 of the 5 patients without complications. After 15+/-10 months, the 4 patients with successful isolation, including 1 who had successful reablation for LA flutter, remained in sinus rhythm without drugs.


CONCLUSIONS
The LSVC can be the arrhythmogenic source of AF with connections to the CS and LA. Ablation of these connections resulted in electrical isolation.
Hsu
Li-Fern
LF
Hôpital Cardiologique du Haut-Lévèque, Bordeaux-Pessac, France. hsulifern@yahoo.com.sg
Jaïs
Pierre
P
Keane
David
D
Wharton
J Marcus
JM
Deisenhofer
Isabel
I
Hocini
Mélèze
M
Shah
Dipen C
DC
Sanders
Prashanthan
P
Scavée
Christophe
C
Weerasooriya
Rukshen
R
Clémenty
Jacques
J
Haïssaguerre
Michel
M
D000318:Adrenergic beta-Agonists; D000328:Adult; D001281:Atrial Fibrillation / Q000209:etiology* / Q000628:therapy; D018880:Atrial Premature Complexes / Q000209:etiology*; D006328:Cardiac Catheterization; D002304:Cardiac Pacing, Artificial; D017115:Catheter Ablation; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007545:Isoproterenol; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome; D014683:Vena Cava, Superior / Q000002:abnormalities* / Q000196:embryology / Q000601:surgery
D000318:Adrenergic beta-Agonists; D007545:Isoproterenol