Down the Wikipedia Rabbit Hole we go:
> During the initial run of [A Fish Called Wanda], a Danish audiologist named Ole Bentzen died while laughing during a screening, which led newspapers to report that he had died from laughter. The official cause of death was heart fibrillation, which may have been caused by an increased heart rate due to extended laughter. Cleese considered using the event for publicity, but ultimately decided it was in too bad taste.