Prolonged postoperative mechanical ventilation was required by 10-20% of cardiac surgery subjects, who constitute a specific group that represents most of the postoperative mortality, which is associated with multiple organ failure and sepsis.

Hospital mortality was higher with prolonged QTc at prehospital-or-hospital admission, given equal Killip, TIMI and APACHE values. Discrimination of Killip, TIMI and APACHE values can be improved with prolonged QTc. Discrimination of a model including Killip, age and prolonged QTc is quite good. We have made a new simple prognostic scale with these variables.