No abstract available.
Syncope*

No abstract available.
Syncope*

No abstract available.
Syncope, Vasovagal*

No abstract available.
Syncope* ; Urination*

BACKGROUND: Oral beta-blocker is initially used to prevent the symptons in patients with vasovagal syncope or presyncope. But, beta-blocker treatment may actually cause worsening of symptoms in some patients. The purpose of the present study was to evaluate the efficacy of oral beta-blocker in preventing symptoms during repeat head-up tilt test in patients who had a positive response in initial head-up tilt test. METHOD: Patients. Among the 150 patients with unexplained syncope or presyncope who underwent head-up tilt from October 1994 to January 1996, forty-three patients, who were taking beta-blocker and underwent repeat head-up tilted test, were included in this study. Initial head-up tilt test. Each patients was tilted to the 70 degree upright position for 30 minutes. If the test was negative in the baseline tilt, intravenous isoproterenol was started at 1 (micro)g/min and then increased by 1 (micro)g/min every three minutes to al maximum of 5 (micro)g/min while maintaining 70 degree upright position. Repeat head-up tilt test. The test was repeated while each patients was taking atinolol. The repeat test was continued until reaching at the stage where each patient had a positive response in initial test. RESULTS: 1) In initial head-up tilt test, most (91%) of a positive response occured during isoproterenol provocation. 2) In repeat head-up tilt test on atenolol, thirty-four patients(79%) had a negative response. But nine patients(21%) still had a positive response. 3) Nonresponsive group showed younger age and shorter time period to a positive response in initial head-up tilt test than responsive group. CONCLUSION: It may be useful to assess the effectiveness of beta-blocker by repeat head-up tilt before deciding long term treatment, especially younger age group.
Adult* ; Atenolol ; Humans ; Isoproterenol ; Syncope* ; Syncope, Vasovagal*

No abstract available.
Diagnosis* ; Syncope, Vasovagal*

No abstract available.
Bradycardia ; Infarction ; Syncope

No abstract available.
Heart Arrest* ; Syncope*

Endocarditis ; Humans ; Syncope

PURPOSE: The purposes of this study were to determine short- and long-term fractal correlation behavior of heart rates during daily activity in patients with neurocardiogenic syncope. METHODS: Twenty five patients with histories of neurocardiogenic syncope episodes were included. Their analogue 24h ambulatory Holter electrocardiograms were analyzed. The tape was digitized and the digitized electrocardiograms were partioned into sections of one hour. Then their RR intervals were measured and 20,000 points of RRI were used. To quantify the fractal correlation behavior, we employed the detrended fluctuation analysis, and short-term(n16, alpha2) fractal scaling exponents were calculated. RESULTS: When compared to control, 24-hour average values of alpha1 and all alpha1 values at quarters of each day were significantly higher in patients with syncope. On the contrary, their 24-hour average value of alpha2 and all alpha2 values at quarters of each day were lower in patients with syncope. However, statistical significances were found in 24-hour average value of alpha2 and in alpha2 value at MN-6AM. CONCLUSION: In the syncope patients with neurocardiogenic syncope, short-term fractal scaling exponents of RR interval was significantly high throughout the day. Therefore, their RR intervals were smoother in the short term scale and had a tendency to continue in the same direction of increase or decrease, which may contribute to persistent decrease in heart rate during a syncopal attack.
Child* ; Electrocardiography ; Fractals* ; Heart Rate* ; Heart* ; Humans ; Syncope ; Syncope, Vasovagal*