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These patients had Q - T prolongation and recurrent syncope due to polymorphous ventricular tachycardia .
 Q - T prolongation, syncope, ventricular tachycardia
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Disease, Chemical 
Text: {0} 
Answer:
 Q - T prolongation, syncope, ventricular tachycardia