Wahl collapsed in the press box while covering Argentina's World Cup quarter-final victory over the Netherlands. Medical staff attempted CPR, but the 48-year-old sadly passed away.
His wife, Dr Celine Gounder, has now revealed the cause of his death.
Speaking to CBS Mornings on Wednesday, she said: "He had an autopsy done here in New York by the New York City medical examiner's office, and it showed that he had an aortic aneurysm that ruptured.
"It's just one of these things that had been likely brewing for years, and for whatever reason it happened at this point in time."
Since his passing, tributes to Wahl have flooded in from across the footballing community.
U.S soccer wrote in a statement: "The entire US soccer family is heartbroken to learn that we have lost Grant Wahl. Fans of soccer and journalism of the highest quality knew we could always count on Grant to deliver insightful and entertaining stories about our game and its major protagonists: teams, players, coaches and the many personalities that make soccer unlike any sport.
"Here in the United States, Grant's passion for soccer and commitment to elevating its profile across our sporting landscape played a major role in helping to drive interest in, and respect for, our beautiful game.
"As important, Grant's belief in the power of the game to advance human rights was, and will remain, an inspiration to all. Grant made soccer his life's work, and we are devastated that he and his brilliant writing will no longer be with us."
World Cup organisers also paid tribute to Wahl by placing a memorial in his assigned seat for England's quarter-final clash with France.
In addition, his image was projected onto the big screens at the Al Bayt Stadium before the game.
Wahl's wife added that the tributes paid to her husband have helped her find strength in the tragedy.
"To know that he was loved by so many people makes me feel a little less alone. It's like a warm hug when you really need it," Gounder said.