1348
This study tested the hypothesis that sodium channel blocking drugs selectively prolong the late potential , or terminal low amplitude signal , portion of the signal - averaged QRS complex and that prolongation of the late potential would correlate with slowing of ventricular tachycardia .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: GENE 
Text: {0} 
Answer:
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