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Introduction Left ventricular (LV) structure and function may be adversely affected by image and performance enhancing drug (IPED) use, however segmental myocardial function in resistance trained (RT) users has not been evaluated and may provide additional sub-clinical insight. We aimed to compare global and regional LV longitudinal strain (basal, mid and apical) and strain patterns between RT IPED users and RT non-user controls.Methods Utilising a cross-sectional design, male (n = 135) RT individuals (age 30 ± 7 years) were grouped based on IPED user status: current (CU; n = 99) and non-users (NU; n = 36). Participants completed an IPED questionnaire, resting blood pressure, anthropometric measurements, bioelectrical impedance analysis and transthoracic echocardiography with strain imaging. Peak longitudinal strain and post systolic shortening index (PSI; myocardial shortening after aortic valve closure) were measured globally and regionally using the 16-segment bullseye. Peak strain dispersion (PSD) was calculated as the standard deviation of the time-to-peak longitudinal strain for all segments. Basal to apical association was quantified by relative apical sparing (RELAPS; defined as average apical longitudinal strain divided by the average of the basal and mid longitudinal strain segments) and the septal longitudinal systolic apex-to-base strain ratio (SAB; defined as the ratio of the septal apical strain to the septal basal strain). Between group differences were analysed using an independent t-test or Mann-Whitney U test.Results Body mass (99.8 ± 15.0 kg vs 85.7 ± 15.3 kg, p < .0001) and FFM (82.0 ± 15.8 kg vs 69.1 ± 9.3 kg) were greater in CU than NU. Current users had a history of IPED use of 7 ± 5 years and over the last month, the average dose was 304 ± 322 mg.wk-1. GLS was lower (less negative) in CU than NU (-15 ± 2% vs -18 ± 2%, p < .001). Aside from the basal posterior segment (p = .053), all peak longitudinal strain segments were lower (less negative) in CU than NU (p < .05), see figure 1. Relative apical sparing (1.23 ± 0.24 vs 1.12 ± 0.17, p = .011) and SAB were significantly higher in CU than NU (1.72 ± 0.73 vs 1.35 ± 0.33, p = .001). PSD was higher in CU than NU (53 ± 23 ms vs 44 ± 11 ms, p = .003). Basal PSI was significantly greater in CU than NU (p < .05), with the exception of the basal posterior segment.Conclusions Resistance trained individuals using IPEDs demonstrated decreased (less negative) longitudinal strain with increased apical predominance and basal dyssnychrony compared to non-users. These findings may be a complex interaction between myocardial structure, collagen deposition and differences in basal susceptibility to pathological loading.Abstract 221 Figure 1Regional left ventricular longitudinal strain. *Denotes significance < 0.05. **Denotes significance < 0.001.Abstract 221 Figure 2Regional left ventricular post systolic shortening index. *Denotes significance < 0.05. ** Denotes significance < 0.001Abstract 221 Table 1Conventional left ventricular parametersVariableCurrent usersMean ± SDNon-usersMean ± SDp-valueLVEDd (mm)57 ± 652 ± 4<.0001LVEDdi (mm.kg-1/3)13.23 ± 1.3812.74 ± 0.930.050LVEDV (ml)168 ± 39135 ± 23<.001LVEDV index (mm.kg-1)2.11 ± 0.901.96 ± 0.380.295LVESV (ml)78 ± 2254 ± 14<.001LVESV index (mm.kg-1)0.97 ± 0.370.80 ± 0.160.001LVM (g)208 ± 87155 ± 32<.001LVM index (g.kg-1)3.17 ± 1.202.26 ± 0.48<.0001SV (ml)91 ± 2180 ± 16.002SV index (ml.kg-1)1.15 ± 0.561.16 ± 0.26.206EF (%)54 ± 559 ± 4<.001GLS (%)-15 ± 2-18 ± 2<.001Lateral S’ (m.s-1)10 ± 312 ± 4.013Medial S’ (m.s-1)8 ± 19 ± 1.039Average S’ (m.s-1)9 ± 210 ± 2.007PSD (ms)53 ± 2344 ± 11.003LVEDd LV end diastolic diameter, LVEDV LV end diastolic volume, LVESV LV end systolic volume, BSA body surface area, RWT relative wall thickness, MWT mean wall thickness, IVS interventricular septum, PW posterior wall, LVM LV mass, SV stroke volume, EF ejection fraction, GLS global longitudinal strain, PSD peak strain dispersion