2023 CiteScore: 0.7
pISSN: 0044-6025
eISSN: 1735-9694
Editor-in-Chief:
Ahmadreza Dehpour, PharmD, PhD
This journal is a member of, and subscribes to the principles of, the Committee on Publication Ethics (COPE).
Vol 38, No 3 (2000)
Exploration of the interlead QT variation (QT dispersion) introduced cardiologists to some new concepts including the deed to define a standard for lead selection in the measurement of QT interval and the reason or factors contributing to QT dispersion. Hoseever, still there dose not exist a generally acceptable standard for lead selection and the reason for the QT dispersion has not been given the importance it deserves. Only a few hypotheses have been suggested, none of which have been seriously experimented. Finding important factors cuusing QT dispersion can lead to a better understanding of its basics and more accurate usage of QT dispersion as and index in clinical practice. This paper examines the "Vector Cancellation Theory" on the basis that if "vector cancellation" affects the QT interval duration in different leads, the ncurest had to rhe mean QR.S axis must have the longest QT interval and vice versa. This was tested on the electrocardiograms taken from 34 people without cardiovascular problems. We came across a statistically significant inverse correlation between the QT interval in each limb lead and its angle to the ECG's mean QRS axis. Thus this study gives weight to the vector cancellation theory. And as the nearest lead to the Mean QRS Axis is likely to have the longest QT interval and given its practicality. It can be suggested as the standard lead for measuring QT internal in an electrocardiogram.
The effects of zinc and mercury on human erythrocyte acetylcholinestrase activity were studied. Blood used in this study was obtained from 24 apparently healthy individuals and after hemolysation, was treted with 3 diferent concentrations of zinc and mercury. Significant suppressions in acetylcholinestrase activity were recorded in treated samples by zinc and mercury. When compared to controls the remaining activity was found to be 53% with the highest concen.tration of zinc (2.1 mg/dl, p<0.01), 72% with the middle (1.4 mg/dl, p<0.01) and 85% with the lowest one (0.7 mg/dl, p<0.01). in the case of mercury, the remaining activity was found to be 55% with the highest concentration (8.4 ng/g , p<0.01 ), 72% with the middle (5.6 ng/g , p<0.01) and 79% with the lowest one (2.8 ng/g , p<0.01). mercury showed a good correlation between doses used and decreases in activity (r=0.98). zinc also showed a linear correlation ( r=0.99). the direct interaction of metal ions with acetylcholinestrase is proposed as a mechanism for depressed enzyme activity. It is concluded that zinc and mercury contamination during acetylcholinestrase measurement can be a source of error that must be taken in to account.
It has been well - established that common atrial flutter is due to intraatrial macroreentry and its reentry circuit locates in the right atrium. This reentry circuit has been characterized to involve an area of slow conduction identifiable electrophysiologically at the low posteroseptal right atrium and anatomical narrow isthmus snrrounded by the inferior vena capa, coronary sinus astium and tricuspid valve annulus. We performed radiofrequency catheter ablation for common atrial futter using anatomical approach in one patient. In this report, we discuss the efficacy of catheter ablative therapy and its results in our patient.
2023 CiteScore: 0.7
pISSN: 0044-6025
eISSN: 1735-9694
Editor-in-Chief:
Ahmadreza Dehpour, PharmD, PhD
This journal is a member of, and subscribes to the principles of, the Committee on Publication Ethics (COPE).
All the work in this journal are licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. |