India, April 8 -- In sad news for fans of Lady Gaga, the American musician cancelled her Montreal concert just hours before taking the stage on April 6, after a respiratory infection worsened. The performance was part of her ongoing Mayhem Ball Tour, and marked her third scheduled show in the city. Announcing the cancellation, the 40-year-old wrote a note on Instagram (see inset left): "I'm so sorry to share that I'm unable to perform tonight and have to cancel the show. I've been fighting a respiratory infection for the past few days and doing everything I can to rest and recover, but it's gotten worse." The singer added that she was unable to deliver the standard that fans expect from her: "My doctor has strongly advised me not to perform today and to be honest, I don't think I could give you the quality of a performance today that you deserve." Calling the decision "heartbreaking", Gaga further shared, "I know how deeply disappointing this is. I truly could not feel worse about letting you down." The Montreal show followed two earlier performances in the city last week. The tour, which began in July last year, is currently slated to conclude on April 13 at Madison Square Garden in New York.htc...