Catheter ablation of atrial tachycardia originated from the
ostium of anomalous drainage between left interior pulmonary vein and
left atrial appendage
Atrial tachycardia (AT) from the
left atrium are well recognized. In most cases, such arrhythmias usually
occur in patients without structural heart disease; the common origin
was identified at mitral annulus, left atrial appendage (LAA) and
pulmonary vein
(PV)1,2.
However, there is no report about AT in patient with anomalous pulmonary
venous drainage. We report one case with focal AT originating from the
ostium of anomalous drainage between left interior PV (LIPV) and LAA.
Case report
An 18-year-old man with paroxysmal AT for six months was referred to our
center for catheter ablation. The echocardiogram did not suggest any
evidence of malformation or structural heart disease and showed a normal
left ventricular ejection fraction. The 24-Holter monitoring reveal high
burden of AT (84.6%) with prolonged sinus pauses (5.38sec) following
the self-termination of AT. The P wave of 12-lead electrocardiogram
(ECG) during the AT is shown in Figure 1B . This patient’s imaging
was obtained by multidetector computed tomography, and using
retrospective electrocardiographic gating (Somatom Definition and Force,
Siemens Medical System, Germany), the axial CT imaging show the
anomalous drainage between LIPV and LAA, and the dilatation of distal
LIPV and the stenosis of proximal LIPV were also observed (Figure
1A ).
The electrophysiology study was performed in the fasting state under
conscious sedation with administration of intravenous fentanyl. The
coronary sinus (CS) activation sequence demonstrated the AT originated
from left atrium (LA) using a 6F decapolar catheter (Diag, St. Jude
Medical Inc., St. Paul, MN, USA); After transseptal puncture,
intravenous heparin was administered to maintain an activated clotting
time of 250 to 350 seconds, an irrigated catheter (Navi-star, Biosense
Webster) was inserted into the LA for mapping and ablation using a CARTO
system. An activation map of the LA revealed that the site of earlier
activity during tachycardia was broad at the LAA ridge and LIPV inferior
ostium; however, the activation time at proximal ABL catheter was
earlier than the distal ABL catheter. We drag back the ABL catheter to
site of ABL34 and mapped the earliest activity with low contact force
(3g, Figure 1C ). The target activation preceded P wave by
39ms (Figure 2, left panel ), the AT elimination was achieved by
ablation at the site of earliest activity after 4 sec (Figure 2,
right panel ). Further inducibility testing with programed stimulation
and burst pacing from the CS was unable to induce any atrial arrhythmia
after successful ablation. The restructure of LA geometry showed the
anomalous drainage between the LIVP and LAA using CARTO system after the
ablation procedure (Figure 3A ). CARTO merge showed the ABL
catheter was located at edge of anomalous drainage between the LIVP and
LAA (Figure 3B ). During six months follow-up, the patient had no
recurrence, regular 24-Holter monitoring did not showed any sinus
pauses.