Keywords:
Ablation procedures, Image manipulation / Reconstruction, CT, Cardiac, Dysplasias
Authors:
T. Ait Ali1, H. Nivet2, M. Salel2, G. Chevreau2, O. Corneloup1, V. Latrabe1, M. Montaudon1, F. Laurent1, H. Cochet1; 1Pessac/FR, 2Bordeaux/FR
Results
Clinical characteristics
Patient characteristics are summarized in Table 1.
All patients had definite ARVC diagnosis according to Task Force criteria.
Of note,
14 (88%) of the patients were implanted with ICDs precluding the use of MRI.
Electroanatomic mapping
All 16 patients were mapped endocardially,
and 13 were mapped epicardially.
The average number of mapping points was 626±335 and 575±279 on RV endocardium and epicardium,
respectively. The bipolar low voltage area was signicantly smaller on the endocardium than on the epicardium (46.6±28.6cm2 versus 115.3±32.2 cm2, P<0.05).
Local abnormal ventricular activities (LAVA) were found and targeted by ablation in all patients.
The number of LAVA sites was 17.3±19.6 on the endocardium,
and 29.0±21.2 on the epicardium.
Relationship between fat on MDCT and voltage
In all patients RV fat was successfully segmented,
mapped,
and integrated in 3D mapping systems.
The extent of fat was 15.6±4.6% of RV free wall.
Fat extent correlated with the extent of low voltage on the endocardium and epicardium (R=0.61,
P=0.012 and R=0.57,
P=0.042).
The agreement between fat and low voltage distributions was good on the epicardium (κ=0.69,
95%CI 0.54-0.84),
but lower on the endocardium (κ=0.41,
95%CI 0.27-0.56). The relationship between fat and low voltage is illustrated in Figure 2.
Relationship between fat on MDCT and ablation targets
Out of a total 653 LAVA sites,
520 (80%) were located within fat areas,
of which 466 (90%) were located less than 20mm from fat borders.
Although 133 (20%) LAVA sites were found outside fat,
125 (94%) of them were no farther than 20mm from its borders.
The relationship between fat and LAVA is illustrated in Figure 3.
In the whole population,
a total of 8 sustained VT circuits were hemodynamically tolerated and could therefore be mapped.
Of these,
7 (89%) were located within fat areas.