Final answer:
Ludwig's angina can lead to asphyxia due to airway obstruction caused by swelling, making it the most immediate life-threatening result of the infection.
Step-by-step explanation:
Ludwig's angina is a type of serious skin infection that occurs in the mouth floor and can rapidly become life-threatening. This condition can lead to asphyxia if the swelling associated with the infection obstructs the airway, thus impeding breathing and resulting in respiratory distress or suffocation. While heart failure, convulsions, paralysis of muscles of respiration, and pyemia are all serious health concerns, asphyxia is the most immediate threat posed by Ludwig's angina due to the potential for airway obstruction.