CREATE TABLE table_name_83 (heat_points INTEGER, date VARCHAR(255), result VARCHAR(255), game VARCHAR(255))
What is the average Heat Points, when Result is "Loss", when Game is greater than 72, and when Date is "April 21"?
    
SQL: SELECT AVG(heat_points) FROM table_name_83 WHERE result = "loss" AND game > 72 AND date = "april 21"