Idiopathic left ventricular arrhythmias originating adjacent to the left aortic sinus of valsalva: electrophysiological rationale for the surface electrocardiogram.
BACKGROUND
Idiopathic ventricular arrhythmias (VAs) may be amenable to catheter ablation within or adjacent to the left sinus of Valsalva (LSOV). However, features that discriminate these sites have not been defined. The purpose of this study was to determine the electrocardiographic and electrophysiological features of VAs originating within or adjacent to the LSOV.


RESULTS
We studied 48 consecutive patients undergoing successful catheter ablation of idiopathic VAs originating from the left coronary cusp (LCC, n = 29), aortomitral continuity (AMC, n = 10) and great cardiac vein or anterior interventricular cardiac vein (Epi, n = 9). A small r wave, or rarely an R wave, was typically observed in lead I during the VAs and pacing in these regions. An S wave in lead V5 or V6 occurred significantly more often during both the VAs and pacing from the AMC than during that from the LCC and Epi (p < 0.05 to 0.0001). For discriminating whether VA origins can be ablated endocardially or epicardially, the maximum deflection index (MDI = the shortest time to the maximum deflection in any precordial lead/QRS duration) was reliable for VAs arising from the AMC (100%), but was less reliable for LCC (73%) and Epi (67%) VAs. In 3 (33%) of the Epi VAs, the site of an excellent pace map was located transmurally opposite to the successful ablation site (LCC = 1 and AMC = 2).


CONCLUSIONS
The MDI has limited value for discriminating endocardial from epicardial VA origins in sites adjacent to the LSOV probably due to preferential conduction, intramural VA origins or myocardium in contact with the LCC.
Division of Cardiovascular Disease, University of Alabama at Birmingham, Birmingham, AL 35294-0019, USA. takumi-y@fb4.so-net.ne.jp
Takumi
T
Yamada
H Thomas
HT
McElderry
Taro
T
Okada
Yoshimasa
Y
Murakami
Harish
H
Doppalapudi
Naoki
N
Yoshida
Yukihiko
Y
Yoshida
Yasuya
Y
Inden
Toyoaki
T
Murohara
Andrew E
AE
Epstein
Vance J
VJ
Plumb
G Neal
GN
Kay
D000293:Adolescent; D000328:Adult; D000368:Aged; D018780:Body Surface Potential Mapping / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012850:Sinus of Valsalva; D017180:Tachycardia, Ventricular / Q000150:complications* / Q000175:diagnosis*; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis* / Q000209:etiology*; D055815:Young Adult