Arthur Wexler, 49, a deputy director of VISTA, the domestic arm of ACTION, the federal volunteer serving agency, died of a heart attack Tuesday while vacationing with his family in Barbados.

"He fought to preserve the mission of VISTA and its service to poor people during politically unfavorable and neglectful times and devoted his life during the last to years to rebuilding and rekindling VISTA's impact on poor communities throughout the United States," VISTA Director Margery Tabankin said in a tribute to him.

As a deputy director, Mr. Wexler had been in charge of recruiting, training and directing more than 3,200 VISTA volunteers.

He began his career with VISTA in 1967, when its programs were part of the Office of Economic Opportunity. He became acting director of the division of plans and management in 1969 and the following year was named director of the plans administration and budget division. From 1972 to December 1975, when he was named deputy director, he was chief of the operations branch.

Mr. Wexler was born in Springfield, Ill. He earned a degree in political science from the University of California at Los Angeles in 1951, and a law degree from Loyola University there in 1961.

He then worked in the congressional liaison office of the State Department; was an aide to Jesse Unruh, the former speaker of the House in the California State Assembly, and a lawyer in private practice in Los Angeles.

Survivors include his wife, the former Dorothy Bradford, and two children, Dorothy and Jacob Winthrop, all of the home in Washington.

The family suggests that expressions of symphathy be in the form of contributions to the Arthur Wexler-VISTA Memorial Fund, ACTION, 806 Connecticut Ave. NW, Washington, D.C. 20525.