select login_name, session_id, host_name, host_process_id
from sys.dm_exec_sessions where host_process_id = XXXX AND session_id = YY

EXEC xp_readerrorlog 0, 1, N'kill', NULL, NULL, NULL, N'DESC'

LogDate                 ProcessInfo  Text
----------------------- ------------ ----------------------------------------------------------------------
2017-06-20 07:17:32.210 spid64       Process ID 62 was killed by hostname JOHNLAPPY, host process ID 7968.

(1 row(s) affected)



select login_name, session_id, host_name, host_process_id from sys.dm_exec_sessions where host_process_id = 7968 AND session_id = 62

login_name              session_id host_name  host_process_id
----------------------- ---------- ---------- ---------------
CONTOSOjohn.eisbrener  62         JOHNLAPPY  7968

(1 row(s) affected)