The illness caused him to drop out of the play and then to retire from the stage .
In 1999 , while preparing for the opening of a play , Berggren suffered a heart ailment in which one of the valves began to malfunction .
The illness caused Berggren to drop out of the play and then to retire from the stage .
In 1999 , while preparing for the opening of a play , Berggren suffered a heart ailment in which one of the valves began to malfunction .