This study explores the effect of cell phone radiofrequency on the heart at three levels: The place of cell phone, presence of ischemic heart disease, and the gender. The results reported in this study show that the radiofrequency of cell phone interferes with the cardiac conduction and the voltage criteria properties in human beings presented with prolongation of QT intervals (measured and corrected). Moreover, the effect of radiofrequency of cell phone on heart is independently related to the gender effect.
The results reported in this study are contrary to those reported by others who found that the cell phone on the precordium in a state of off, on, and ringing did not show significant effects on the blood pressure, heart rate, P
-wave dispersion, QT dispersion, and QT-corrected dispersion parameters.[16
] Further, it was reported in a study that the electromagnetic field emitted by mobile Global System for Mobile Communication (GSM) phone did not interfere with the time or frequency of heart rate variability domain in humans.[9
The results of this study may be explained on the basis of the biological effects of electromagnetic energy radiated from mobile on human tissues. It is well known that the radiofrequency of mobile phone exerts three forms of effects on humans: Heating, interference with action potential of excitable tissue, and interference with electrophysiological machine record. The mobile phone radiates electromagnetic energy which is partly absorbed into the tissues. The slight heating, of maximum up to 0.3°C, may cause some alterations in the expression of genes and proteins.[17
] Exposure to radiofrequency electromagnetic field is associated with overproduction of reactive oxygen species in the brain of rat.[18
] Barth et al
. reported that the cognitive abilities neither impaired nor facilitated electromagnetic fields emitted by GSM and Universal Mobile.[19
] Neither heating nor overproduction of reactive oxygen species explain the cardiac effect of mobile in this study because the subjects were exposed to short duration of electromagnetic energy (40 sec). Yuasa et al
. reported that the radiofrequency of mobile phone has no short-term (30 min) effects on the healthy human somatosensory evoked potential of sensory cortex.[20
] In patients with ventricular tachycardia and/or fibrillation treated with transvenous pectoral implantable cardioverter defibrillators, the radiofrequency of mobile phones has no effects on the defibrillators’ function.[21
] On the other hand, it was reported that the mobile cells are a potential source of electromagnetic interference to ECG recording machine and are responsible for poor-quality ECG recordings.[22
] Literature survey did not show the effect of mobile phones on the QT interval of the ECG records in patients with cardiac diseases. Furthermore, the results of this study indicated that men are more vulnerable than women to the effect of mobile cell on the ECG parameters. Previous studies showed that the 900 MHz exposure did not appear to affect the concentrations or the circadian rhythm of prolactin, thyroid stimulating hormone, adrenocorticotrophic hormone, and testosterone hormone in men.[23
] One of the study limitations is the measurement of sex hormones in order to linkthe changes in their levels with the effect of mobile. Further studies are recommended to explore the effect of gender on the human susceptibility to the radiofrequency of mobile.
It can be concluded that the radiofrequency of cell phone prolonged the QT interval in human beings with or without ischemic heart disease and it interferes with voltage property of ECG records in patients with myocardial ischemia, of which female patients are immune from these effects.