Abstract Funding Acknowledgements Type of funding sources: None. Background The distribution of J waves and the presence of organized left ventricular (LV) myocardial damage may be related in survivors of ventricular fibrillation (VF). Purpose To predict the presence of organized myocardial damage such as fibrotic or fat change on cardiac computed tomography (CT) using the distribution of J waves in survivors of VF. Methods We conducted a retrospective analysis of 21 survivors of VF (17 males; mean age, 61 ± 14 years) that were implanted with a cardioverter defibrillator and underwent cardiac CT. Results On ECG, 4 patients had atrial fibrillation and 15 had J waves. On CT, 13 patients had organized LV myocardial fibrotic and/or fat change in myocardium. The mean corrected QT interval was 453 ± 30 and 429 ± 48 msec in patients with and without myocardial fibrotic and/or fat change, respectively (P = 0.182). The distribution of J waves was as follows: 5 had J waves in II, III and aVF leads (one had myocardial fibrotic and/or fat change) and 2 had J waves in III lead (one had myocardial fibrotic and/or fat change). One patient each had J waves in V1 lead; V1,2 leads; II, III, aVF and V1-3 leads; I, III, aVF and V1 leads; II, III, aVF, aVL and V1-6 leads; II, III, aVF and V4,5 leads; II, III, aVF and V2-5 leads; and III and aVF leads. The first one did not have myocardial fibrotic and/or fat change and the remaining 6 had myocardial fibrotic and/or fat change. If the J waves reached to ≥1 of 3 LV inferior wall leads (II, III, aVF leads) (N = 13), 10 (77%) had LV myocardial fibrotic and/or fat change. If not (N = 8), 3(38%) had LV myocardial fibrotic and/or fat change (P = 0.071). If the J waves reached ≥2 of 3 LV inferior wall leads (N = 11), 9 (82%) had LV myocardial fibrotic and/or fat change. If not (N = 10), 4 (40%) had LV myocardial fibrotic and/or fat change (P = 0.049). If the J waves reached all three LV inferior wall leads (N = 10), 8 (80%) had LV myocardial fibrotic and/or fat change. If not (N = 11), 5 (46%) had LV myocardial fibrotic and/or fat change (P = 0.104). Conclusions In survivors of VF, if the J waves reached ≥2 of 3LV inferior wall leads, the frequency of organized LV myocardial fibrotic and/or fat change was significantly higher than those without. Furthermore, the distribution of J waves and the presence of myocardial fibrotic and/or fat change on CT may predict VF. Abstract Figure. CT fibrosis in VF survivors with HCM