title: Prolongation of QT interval and ventricular septal hypertrophy.
abstract: Long QT syndrome (LQTS) is a prime example of interplay between molecular biology, cellular physiology, and organ physiology. Both the congenital and acquired forms of LQTS are due to intrinsic and/or acquired abnormalities of the ionic currents responsible for cardiac repolarization. We analyzed the QTc interval, QRS axes and interventricular septal thickness (IVST) in 41 patients who had a prolonged QT interval on routine electrocardiography (ECG) (5 females and 36 males, mean age 65+/-13 years). The QRS axis of patients in the LQTS group (27+/-49 degrees) was significantly lower (p < 0.05) than in the control group (46+/-26 degrees). However, the IVST in the LQTS group (10+/-2 mm) was significantly thicker than in the control group (9+/-1 mm) (p < 0.05), while the WTd was not significantly different. The QTc interval in patients with ventricular septal hypertrophy (IVST > or = 12 min, 478.8+/-7.9 msec) was significantly longer (p < 0.05) than in the normal group (IVST < 12 mm, 472.1+/-17.5 msec). In conclusion, the results of this preliminary study suggest that prolongation of the QT interval on ECG should prompt screening for electrocardiographic evidence of ventricular hypertrophy in patients with this disease.
authors.affiliation: Department of Laboratory Medicine, Gunma University School of Medicine, Maebashi, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Kotajima
authors.forename: T
authors.initials: T
authors.lastname: Hirakata
authors.forename: T
authors.initials: T
authors.lastname: Kanda
authors.forename: T
authors.initials: T
authors.lastname: Yokoyama
authors.forename: Y
authors.initials: Y
authors.lastname: Hoshino
authors.forename: T
authors.initials: T
authors.lastname: Tanaka
authors.forename: J
authors.initials: J
authors.lastname: Tamura
authors.forename: R
authors.initials: R
authors.lastname: Nagai
authors.forename: I
authors.initials: I
authors.lastname: Kobayasii
mesh_terms: D000328:Adult; D000368:Aged; D004562:Electrocardiography; D005260:Female; D006346:Heart Septum / Q000000981:diagnostic imaging / Q000473:pathology*; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000000981:diagnostic imaging / Q000473:pathology*; D008133:Long QT Syndrome / Q000000981:diagnostic imaging / Q000209:etiology / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D014463:Ultrasonography