542
Using a nested case - control design , 477 cases of bradyarrhythmia requiring a permanent pacemaker were matched ( 1 : 4 ) to 1 , 908 controls .
 Disease: bradyarrhythmia
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Disease, Chemical 
Text: {0} 
Answer:
 Disease: bradyarrhythmia