James Harden and Isiah Thomas are tied for the most assists in a game with 45+ points, with 17 assists.

Interpreted as:

Highest assisting regular-season game with 45+ points by a player

	NAME	AST	PTS	DATE	TM		OPP	MIN	REB	STL	BLK	FGM	FGA	FG%	3PM	3PA	3P%	FTM	FTA	FT%	TS%	OREB	DREB	TOV	PF	+/-
1	James Harden J. Harden	17	53	12/31/2016	HOU	vs	NYK	42	16	0	0	14	26	53.8	9	16	56.3	16	18	88.9	78.1	3	13	8	2	+13
2	Isiah Thomas I. Thomas	17	47	12/13/1983	DET	@	DEN	52	5	4	1	18	34	52.9	1	2	50.0	10	19	52.6	55.5	2	3	2	5
3	Trae Young T. Young	16	49	3/1/2019	ATL	vs	CHI	56	8	1	1	17	33	51.5	6	13	46.2	9	11	81.8	64.7	1	7	9	2	-9
4	Luka Dončić L. Dončić	15	45	1/29/2024	DAL	vs	ORL	43	9	2	0	12	23	52.2	3	8	37.5	18	21	85.7	69.8	0	9	4	4	+3
5	Luka Dončić L. Dončić	15	50	12/25/2023	DAL	@	PHX	44	6	4	3	15	25	60.0	8	16	50.0	12	12	100.0	82.6	1	5	4	2	+16
6	Gail Goodrich G. Goodrich	15	47	3/9/1969	PHX	vs	SDR	46	8			16	32	50.0				15	18	83.3	58.9				3
7	Luka Dončić L. Dončić	14	45	2/27/2024	DAL	@	CLE	41	9	3	0	17	29	58.6	6	11	54.5	5	5	100.0	72.1	0	9	1	1	+13
8	Trae Young T. Young	14	45	11/30/2023	ATL	@	SAS	40	4	2	0	15	29	51.7	2	9	22.2	13	16	81.3	62.4	0	4	2	1	-1
9	Trae Young T. Young	14	56	1/3/2022	ATL	@	POR	37	4	0	0	17	26	65.4	7	12	58.3	15	15	100.0	85.9	1	3	4	1	+10
10	Trae Young T. Young	14	45	1/26/2020	ATL	vs	WAS	39	6	1	0	13	24	54.2	6	11	54.5	13	16	81.3	72.5	1	5	5	2	+22
11	Kenny Anderson K. Anderson	14	45	4/15/1994	NJN	vs	DET	48	8	4	0	12	26	46.2	1	4	25.0	20	23	87.0	62.3	4	4	3	3
12	Nate Archibald N. Archibald	14	52	1/9/1973	KCO	vs	NYK	53	3			18	28	64.3				16	17	94.1	73.3				1
13	Nate Archibald N. Archibald	14	51	11/18/1972	KCO	vs	HOU	48	1			17	34	50.0				17	18	94.4	60.8				4
14	Wilt Chamberlain W. Chamberlain	14	53	3/18/1968	PHI	vs	LAL	48	32			24	29	82.8				5	10	50.0	79.3				0
15	Oscar Robertson O. Robertson	14	46	2/15/1967	CIN	vs	NYK	47	5			15	28	53.6				16	17	94.1	64.8				3
16	Luka Dončić L. Dončić	13	45	12/15/2024	DAL	@	GSW	38	11	3	2	16	23	69.6	6	11	54.5	7	9	77.8	83.5	2	9	3	1	+18
17	Trae Young T. Young	13	48	2/9/2020	ATL	vs	NYK	48	1	2	0	13	30	43.3	6	13	46.2	16	16	100.0	64.8	0	1	7	1	+10
18	Damian Lillard D. Lillard	13	50	1/26/2020	POR	vs	IND	38	6	1	0	14	23	60.9	8	12	66.7	14	16	87.5	83.2	0	6	1	0	+19
19	James Harden J. Harden	13	54	11/26/2018	HOU	@	WAS	47	8	3	0	17	32	53.1	7	15	46.7	13	15	86.7	69.9	1	7	11	4	+7
20	James Harden J. Harden	13	56	11/5/2017	HOU	vs	UTA	35	2	2	0	19	25	76.0	7	8	87.5	11	12	91.7	92.5	0	2	7	3	+25
21	James Harden J. Harden	13	51	1/27/2017	HOU	@	PHI	39	13	2	1	16	28	57.1	6	11	54.5	13	14	92.9	74.6	1	12	5	4	+13
22	Gilbert Arenas G. Arenas	13	45	12/18/2009	WAS	@	GSW	43	3	0	1	15	25	60.0	4	10	40.0	11	16	68.8	70.2	1	2	5	2	+17
23	Tracy McGrady T. McGrady	13	46	2/23/2003	ORL	@	NJN	45	10	0	2	16	27	59.3	3	8	37.5	11	13	84.6	70.3	0	10	4	0	+7
24	Antoine Walker A. Walker	13	47	1/17/2001	BOS	@	SAC	45	5	4	1	16	29	55.2	9	14	64.3	6	10	60.0	70.4	0	5	5	3	-5
25	Michael Jordan M. Jordan	13	47	4/13/1989	CHI	@	IND	46	11	4	2	17	30	56.7	0	1	0.0	13	14	92.9	65.0	2	9	4	3