Non-Cartesian imaging can suffer from local blurring caused by concomitant fields and off-resonance. Concomitant fields are especially problematic when using prolonged non-Cartesian readouts with high gradient amplitudes at lower field strengths. We present a new reconstruction method, denoted MaxGIRF, for non-Cartesian imaging that corrects concomitant fields and trajectory errors without specialized hardware. The proposed method utilizes gradient impulse response functions to predict gradients waveforms which are in-turn used to estimate concomitant fields with analytic expressions. Image artifacts were successfully mitigated by the proposed method from 2D SE spiral imaging of the human brain acquired on a prototype 0.55T MRI system.