According to Qualcomm, Yes...

Audio performance on the Samsung Galaxy Note8 is greatly improved over previous generations with the inclusion of the Qualcomm Aqstic™ audio codec (WCD9341) and Qualcomm® aptX™ HD. The WCD9341 is the next-generation industry leading 40nm audio codec, which supports Hi-Fi quality audio with PCM up to 384kHz/32bit @ 130db dynamic range and THD+N @ -109db right out of the high-quality headphone jack. aptX HD delivers 24-bit audio over a Bluetooth wireless connection. As well as accepting a 24-bit audio input, 24-bit audio resolution is maintained by using an extra two bits in each of the four sub-bands of processing.)

However, it does not seem as if Samsung has enabled it. Opting instead to push their own UHD tech that only works with Samsung audio gear.

My new Sony WH1000XM2 headphones do NOT connect to the Note 8 in AptXHD (which the headphones do support), or even regular AptX for that matter, but rather standard A2DP SBC with Sony's own DSEE HX upscaler tech layered on top. When I connect them to my older Note 10.1 tablet, they do connect in AptX mode and the difference is audible if the source material is of high quality.

Presumably, the LDAC codec, plus the ability to manually select your supported codec will be supported when Oreo drops. My WH1000XM2's still sound good on the Note 8 and I only imagine it will get even better when improved bluetooth audio support arrives.