Many Nights at the Opera Involve Emergency Room

When the tenor Gary Lehman slid down the raked stage into the prompter’s box on Tuesday night during Wagner’s “Tristan und Isolde” at the Metropolitan Opera, stopping the show at the start of Act III, he entered a storied history of midperformance mishaps at the opera.

“Tristan und Isolde” has long been a magnet for trouble. Ludwig Schnorr von Carolsfeld, the first Tristan, died of a heart attack in Munich in 1865, at 29, within weeks of the premiere, leaving the first Isolde — his wife, Malvina — a widow.

In 1959, when each of three possible Tristans announced, one after another, that he was too ill to perform at the Met, Rudolf Bing, the opera’s legendary general manager, persuaded each to sing one of the three acts.

after singing the line “You can only live so long” from a ladder minutes into the Met premiere of Janacek’s “Makropulos Case” in 1996, Richard Versalle fell 10 feet to the stage, having suffered a fatal heart attack at 63