Repetitive monomorphic ventricular tachycardia originating from the aortic sinus cusp: electrocardiographic characterization for guiding catheter ablation.
OBJECTIVE
We sought to investigate the electrocardiographic (ECG) characteristics for guiding catheter ablation in patients with repetitive monomorphic ventricular tachycardia (RMVT) originating from the aortic sinus cusp (ASC).


BACKGROUND
Repetitive monomorphic ventricular tachycardia can originate from the right ventricular outflow tract (RVOT) and ASC in patients with a left bundle branch block (LBBB) morphology and an inferior axis.


METHODS
Activation mapping and ECG analysis was performed in 15 patients with RMVT or ventricular premature contractions. The left main coronary artery (LMCA) was cannulated as a marker and for protection during radiofrequency delivery if RMVT originated from the left coronary ASC.


RESULTS
During arrhythmia, the earliest ventricular activation was recorded from the superior septal RVOT in eight patients (group 1) and from the ASC in the remaining seven patients (group 2). The indexes of R-wave duration and R/S-wave amplitude were significantly lower in group 1 than in group 2 (31.8+/-13.5% vs. 58.3+/-12.1% and 14.9+/-9.9% vs. 56.7+/-29.5%, respectively; p < 0.01), despite similar QRS morphology. In five patients from group 2, RMVT originated from the left ASC, with a mean distance of 12.2+/-3.2 mm (range 7.3 to 16.1) below the ostium of the LMCA. In the remaining two patients, the RMVT origin was in the right ASC. All arrhythmias were successfully abolished. None of the patients had recurrence or complications during 9+/-3 months of follow-up.


CONCLUSIONS
On the surface ECG, RMVT from the ASC has a QRS morphology similar to that of RVOT arrhythmias. The indexes of R-wave duration and R/S-wave amplitude can be used to differentiate between the two origins. Radiofrequency ablation can be safely performed within the left ASC with a catheter cannulating the LMCA.
Ouyang
Feifan
F
II. Med. Abteilung, Allgemeines Krankenhaus St. Georg, Hamburg, Germany. Ouyangfeifan@aol.com
Fotuhi
Parwis
P
Ho
Siew Yen
SY
Hebe
Joachim
J
Volkmer
Marius
M
Goya
Masahiko
M
Burns
Mark
M
Antz
Matthias
M
Ernst
Sabine
S
Cappato
Riccardo
R
Kuck
Karl Heinz
KH
D000293:Adolescent; D000328:Adult; D000368:Aged; D018780:Body Surface Potential Mapping; D002037:Bundle-Branch Block / Q000150:complications / Q000601:surgery; D017115:Catheter Ablation; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008131:London; D008297:Male; D008875:Middle Aged; D012850:Sinus of Valsalva / Q000503:physiopathology / Q000601:surgery; D017180:Tachycardia, Ventricular / Q000150:complications* / Q000601:surgery