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Our results reveal how ECG , the novel I ( Na ) agonist , may act as a promising candidate in clinical applications on cardiac arrhythmias .
 Chemical: ECG; Chemical: Na
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: ECG; Chemical: Na