Post myocardial ischemia-associated torsades de pointes in a patient carrying a KCNQ1 G643S variant.
Polymorphic ventricular tachycardia, which occurs during the subacute phase of myocardial infarction (MI) or ischemia and is not related to ongoing ischemia, has recently been reported. It has characteristics of typical pause-dependent torsades de pointes (TdP) following excessive QT prolongation (post MI/ischemia-associated TdP). We describe a male patient with post MI/ischemia-associated TdP. The patient experienced recurrent TdP with excessive QT prolongation 2 days after transient myocardial ischemia. Genetic screening of the major LQTS-causing genes identified a KCNQ1 G643S variant. This gene variant could be a genetic predisposition to the development of TdP during the subacute phase of MI/ischemia.
Department of Medicine and Biological Science, Gunma University Graduate School of Medicine, Maebashi. tnakajim@med.gunma-u.ac.jp
Tadashi
T
Nakajima
Yoshiaki
Y
Kaneko
Akihiro
A
Saito
Tadanobu
T
Irie
Toshimitsu
T
Kato
Tatsuya
T
Iso
Masahiko
M
Kurabayashi
D000368:Aged; D020022:Genetic Predisposition to Disease; D014644:Genetic Variation / Q000235:genetics*; D006801:Humans; D051657:KCNQ1 Potassium Channel / Q000235:genetics*; D008133:Long QT Syndrome / Q000150:complications / Q000175:diagnosis; D008297:Male; D017202:Myocardial Ischemia / Q000150:complications* / Q000235:genetics*; D016171:Torsades de Pointes / Q000209:etiology* / Q000235:genetics*
D051657:KCNQ1 Potassium Channel; C496909:KCNQ1 protein, human