A heat pipe apparatus having a sintered lattice wick structure includes a plurality of wicking walls having respective length, width and heights and spaced in parallel to wick liquid in a first direction along the respective lengths, the respective lengths being longer than the respective widths and the respective heights, the plurality of wicking walls being adjacent to one another and spaced apart to form vapor vents between them, a plurality of interconnect wicking walls to wick liquid between adjacent wicking walls in a second direction substantially perpendicular to the first direction, and a vapor chamber encompassing the sintered lattice wick structure, the vapor chamber having an interior condensation surface and interior evaporator surface, wherein the plurality of wicking walls and the plurality of interconnect wicking walls are configured to wick liquid in first and second directions and the vapor vents communicate vapor in a direction orthogonal to the first and second directions.