The pair are three-time Grand Slam winners, but for Heliovaara it's a last-eight appearance in New York just for the second time in his career after 2022, while Patten has never reached the stage before.
Despite the unchartered territory as a duo, victory over Cabral and Tracy is their third two-set win of the competition so far, and they are yet to be forced into a tiebreak.
The number one seeds' great form was on display from the off in the third round, as they forced a loss of serve in the very first game, and though they had to save four break points in a mammoth eighth game, they had done enough for the 6-4 win in the first set.
One break was all they needed in the second set, too, forcing the loss at the second time of asking to go 4-3 ahead. The Portuguese and American duo missed the chance to break back in game 10, but Heliovaara and Patten took the next three points to win the set 6-4 and the match 2-0 in one hour and 10 minutes.
In the quarter-finals, the world number one pair will face the seventh seeds, Guido Andreozzi of Argentina and Manuel Guinard of France, in what is sure to be a tough end to the competition, with seeds one to seven all making it through to the last eight.