PO-03-107 MYOCARDIAL SCAR CHARACTERISTICS BY 3D-LGE CANNOT FULLY EXPLAIN DIFFERENT ARRHYTHMIC EVENT RATES IN PRIMARY AND SECONDARY PREVENTION OF SUDDEN CARDIAC DEATH

There is a noticeable difference in the incidence of ventricular arrythmias among patients receiving defibrillator devices (ICD or CRT-D) for primary vs. secondary prevention sudden cardiac death (SCD). The underlying reasons this remain to be fully explained. To assess differences myocardial scar characteristics between who had implanted scenarios, and their correlation with arrhythmic events. In single center retrospective study, underwent late gadolinium enhancement (LGE) MRI clinical purposes before implantation an ICD CRT-D were included. Patients channelopathies (n=2) inappropriate imaging quality (n=7) excluded. We used ADAS software perform characterization 3D-LGE datasets all but 16 patients, which 2D used. endpoint was composite appropriate therapy (appropriate shock ATP), sustained tachycardia SCD. A total 116 (mean age 66±14 years, 81% male) included, 40 (35%) prevention. During median follow-up 28 months (IQR 16-24), 23 events identified (18 therapy, 9 shocks ATP; 2 SCD; 3 VT), 7 (30.4%) group, (69.6%) group. event rate significantly higher setting (15.0 per 100 persons-year [95% CI 7.7 – 22.4] 4.1 1.1 7.1]; p < 0.001). Despite LVEF group (41 ± 14% 30 13%; p-value 0.001), no statistically significant found regarding tissue characteristics, namely borderzone (BZ) mass, channel largest number channels heterogeneity (BZ mass / ratio) Table. prevention, both groups. These findings suggest that risk unlikely explained solely by anatomical substrate, support greater role interplay substrate transient triggers.Tabled 1Primary PreventionSecondary Preventionp-valueScar + BZ (g)26.2 13.3 - 35.0)23.7 11.4 33.4)p = 0.322Scar percentage (%)18.0 11.0 27.0)17.0 9.0 26.0)p 0.545BZ (g)17.7 11.1 24.2)14.8 8.8 22.0)p 0.350BZ (%)13.0 8.0 18.0)11.0 6.0 17.0)p 0.677Scar (g)6.6 3.4 11.0)6.9 2.0 10.3)p 0.693Scar (%)4.0 9.0)5.0 1.0 8.0)p 0.695Scar heterogeneity2.4 1.7 3.9)2.7 1.5 4.4)p 0.797Total (g)3.0 0.7 4.9)1.8 0.0 5.0)p 0.215Biggest (g)1.4 0.5 2.5)0.8 3.0)p 0.163Number channels3.0 5.0)3.0 0.520BZ, Borderzone Open table new tab