A brazed plate heat exchanger (30) is provided for transferring heat between a first fluid (32) and a second fluid (34), with the first fluid (32) being pressurized to a relatively high pressure. The heat exchanger includes plate pairs (41), with each pair (41) defining a plurality of flow channels (56) for the first fluid (32). Each of the flow channels (56) has a hydraulic diameter less than 1 mm. Reinforcements (62) are provided between each of the plate pairs (41) and are aligned with inlet and outlet openings (46,48) to define inlet and outlet manifolds (50,52) for the first fluid (32).