title: Pronounced ST-segment depression during paroxysmal supraventricular tachycardia.
abstract: To determine the clinical significance of ST-segment depression observed in paroxysmal supraventricular tachycardia (PSVT), we evaluated the 12-lead electrocardiogram (ECG) during spontaneous PSVT in 54 patients (27 men and 27 women: mean age +/- SD; 47 +/- 18 years), who came to our clinic for the treatment of PSVT. Coronary angiography was performed in 16 patients (16 to 74 years; mean = 50 +/- 18) and treadmill exercise testing was performed in 21 patients. A cardiac electrophysiological study was carried out in 24 patients. During PSVT, ST-segment score was calculated as the sum of the ST-segment depression in 12 leads. The correlations between the ST-segment score, PSVT rate and age of the patient were analyzed as follows: The most significant positive correlation was observed between the ST-segment score and the PSVT rate (r = 0.615, p < 0.000001). The next most significant correlation was found between the PSVT rate and the age of the patient (r = -0.500, p = 0.00011). A negative correlation was also observed between the ST-segment score and the age of the patient (r = -0.429, p = 0.0012). In 13 of 16 patients, coronary angiography did not reveal any significant (> or = 75% in area) stenosis. Exercise testing induced significant ST-segment depression in 3 patients, of whom two had significant coronary artery lesions. PSVT was due to atrioventricular reentry via an overt (n = 3) or concealed accessory pathway (n = 15), atrioventricular nodal reentry (n = 5) and sinus node reentry (n = 1). In conclusion, patients with a faster PSVT rate revealed more pronounced ST-segment depression than did those with a slower PSVT rate, possibly reflecting the modified repolarization process instead of coronary artery involvement.
authors.affiliation: Department of Cardiology, Koshigaya Hospital, Dokkyo University School of Medicine, Saitama, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Takayanagi
authors.forename: H
authors.initials: H
authors.lastname: Hoshi
authors.forename: M
authors.initials: M
authors.lastname: Shimizu
authors.forename: T
authors.initials: T
authors.lastname: Inoue
authors.forename: Y
authors.initials: Y
authors.lastname: Sakai
authors.forename: S
authors.initials: S
authors.lastname: Morooka
authors.forename: Y
authors.initials: Y
authors.lastname: Takabatake
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D017023:Coronary Angiography; D004562:Electrocardiography; D004594:Electrophysiology; D005080:Exercise Test; D005260:Female; D006321:Heart / Q000503:physiopathology; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D013614:Tachycardia, Paroxysmal / Q000000981:diagnostic imaging / Q000503:physiopathology*; D013617:Tachycardia, Supraventricular / Q000000981:diagnostic imaging / Q000503:physiopathology*