Acoustic orbital angular momentum (OAM) provides a spatial degree of freedom for sound communication. Reliable demultiplexing with sparse receivers, however, remains limited by finite sampling, modal crosstalk, propagation loss, and channel mismatch. Existing receivers are commonly based on scalar pressure measurements and therefore do not directly exploit the local directional information contained in the particle-velocity field. Here we develop a Cartesian acoustic-vector-sensor (AVS) reception framework for acoustic OAM links. Co-located pressure and particle-velocity components are assembled into a whitened effective receiving matrix, enabling pressure-only, transverse-AVS, and full Cartesian-AVS reception to be compared under a unified noise and normalization convention. Numerical studies show that vector observations improve the detection geometry in the whitened receiver space, reduce the signal-to-noise ratio required to reach prescribed bit-error-rate targets, and enhance robustness against receiver offset, transmission-distance variation, finite pilot calibration, and transmitter or receiver amplitude-phase errors. A gap-aperture image-payload example further shows that full AVS reception reduces payload bit errors and improves binary image reconstruction. These results identify joint pressure-particle-velocity sensing as an effective receiver-side strategy for robust sparse-aperture acoustic OAM communication.