The Americans stretched their team-record win streak to 11 matches and claimed their fifth Gold Cup crown after previously taking the title in 1991, 2002, 2005 and 2007. Every edition of the event has been played on US soil.
"It's an unbelievable feeling," USA captain DaMarcus Beasley said. "I'm at a loss for words. I'm so excited. This is what it's about, winning championships together."
The decisive moment came when a USA centering pass was deflected toward the Panama goal. Onrushing Landon Donovan, the all-time national team goalscorer, raced for the ball and attracted the attention of Panama's defenders.
But the ball rolled past Donovan's outstretched foot and toward the far side of the yawning goal, where Shea raced forward and tapped it across the line.
"I tried to shoot it. It wasn't my finest moment," Donovan said. "But fortunately Brek was there to put it in.
"It has meant a lot to all of us. We had a dream and a goal and I think we once again showed the American experience."
Donovan has not played in a 2014 FIFA World Cup Brazil™ qualifier this year after having taken almost four months off between seasons for the Los Angeles Galaxy.
But the 31-year-old striker could be poised to return to the top squad for the next US FIFA World Cup qualifier on 6 September in Costa Rica and play a key role if the Americans, who top the qualifying table, reach Brazil 2014.
"We'll see for the World Cup," Donovan said. "We have a lot of guys who weren't here for the qualifying. We want to keep pushing each other and keep getting better and better."
Not all was good news for the US side, however, as Stuart Holden went off with a sprained knee.
Andreas Herzog served as the replacement coach in the match for USA coach Jurgen Klinsmann, the former German international star who was banned for the match after being sent off in the 87th minute of the semi-final against Honduras for complaining to the referee.
It was a loss to Mexico in the 2011 Gold Cup final that prompted USA Soccer to dump then-coach Bob Bradley, now the coach of Egypt, and hire Klinsmann.
Overall, the Americans are 12-2-2 this year and their win streak includes three FIFA World Cup qualifying triumphs and a friendly victory over Germany last month as well as an unbeaten Gold cup run.
The victory earns USA a spot in a two-team play-off against the winner of the 2015 Gold Cup. The winner of those contests will clinch a berth in the 2017 FIFA Confederations Cup.