Do Mobile Phones Pose a Potential Risk to Autonomic Modulation of the Heart?

Background: It has long been speculated that mobile phones may interact with the cardiac devices and thereby cardiovascular system may be a potential target for the electromagnetic fields emitted by the mobile phones. Therefore, the present study was designed to test possible effects of radiofrequency waves emitted by digital mobile phones on cardiac autonomic modulation by short‐time heart rate variability (HRV) analysis. Methods and Results: A total of 20 healthy young subjects were included to the study. All participants were rested in supine position at least for 15 minutes on a comfortable bed, and then time and frequency domain HRV parameters were recorded at baseline in supine position for 5 minutes. After completion of baseline records, by using a mobile GSM (Global System for Mobile Communication) phone, HRV parameters were recorded at turned off mode, at turned on mode, and at calling mode over 5 minutes periods for each stage. Conclusion: Neither time nor frequency domain HRV parameters altered significantly during off mode compare to their baseline values. Also, neither time nor frequency domain HRV parameters altered significantly during turned on and calling mode compared to their baseline values. Short‐time exposure to electromagnetic fields emitted by mobile phone does not affect cardiac autonomic modulation in healthy subjects. (PACE 2011; 34:1511–1514)     

Arterial stiffness and dipper/nondipper blood pressure status in women with preeclampsia

Introduction  The aim of this study was to investigate the clinical relevance of dipper status in women with preeclampsia by comparing arterial stiffness index (SI) values, and dipper and nondipper status. Methods  A total of 60 pregnant women in their third trimester were enrolled in the study. SI values were measured using a digital photoplethysmographic method (Pulse Trace System, Micro Medical Ltd., Gillingham, Kent, UK). Twenty-four-hour ambulatory blood pressure was measured by a SpaceLabs 90217 oscillometric device (SpaceLabs Inc., Redmond, WA, USA). Systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and pulse pressure (PP) were recorded. Those preeclamptic women whose mean nighttime blood pressure measurements were at least 10% lower compared with mean daytime measurements were classified as dipper status, and those with a decrease of less than 10% were classified as nondipper status. Results  Seventeen women were preeclamptic with a dipper status, 13 women had nondipper status preeclampsia, and 30 women were normotensive. SI values were significantly higher in preeclamptic women compared with normotensive women (8.8±1.2 m/s vs. 5.9±0.8 m/s, P<0.001), but SI values of preeclamptic women with dipper status and preeclamptic women with nondipper status did not differ significantly from each other (P=0.485). Conclusion  There was no significant difference in SI values between the dipper and nondipper preeclamptic groups. These results indicate that dipper and nondipper measurements may not be suitable for clinical follow-up of preeclamptic women.     

Effects of different dialysis modalities on cardiac autonomic dysfunctions in end-stage renal disease patients: one year prospective study

Cardiac autonomic dysfunction (CAD) is a common problem in patients with end-stage renal disease (ESRD) and may contribute to the risk of cardiac mortality. Long-term effects of dialysis modalities on CAD in ESRD patients are not clear. In this one-year prospective study, we studied the effects of different dialysis modalities on CAD in ESRD patients. The study consisted of 20 ESRD patients who had the indications for initiating dialysis therapy (13 hemodialysis and 7 CAPD patients) and 15 healthy controls (M/F: 5/10; age 30 +/- 4). In all the subjects, first at the beginning of study (in patient groups just before initiating dialysis therapy) and then after 12 months, we studied 24 hours ECG-Holter monitoring and heart rate variability parameters (time and frequency domain analysis parameters; SDNN: standard deviations of nn intervals, rMSSD: square root of the median of standard deviation, HRVI: heart rate variability index, LF/HF: low frequency/high frequency). In ESRD patients, before dialysis therapy, all the parameters of time domain analysis were significantly lower compared to control group (p = 0.001). In patient groups, after dialysis therapy (on the 12th month), significant improvement was observed in time domain analysis parameters (p = 0.001). When dialysis modalities were compared, the increase in the time domain analysis parameters was significantly greater in the CAPD group compared to hemodialysis (HD) group. Our findings suggest that CAD is frequent in ESRD patients, a dialysis therapy of 12 months can cause significant improvement on CAD and the ameliorative effect of CAPD is better than HD.     

QT dispersion in patients with polycystic ovary syndrome

Cardiac risk factors are observed more frequently in patients with polycystic ovary syndrome (PCOS). On the other hand, increased QT dispersion, which is a risk factor for cardiac arrhythmias and sudden death, has not been investigated in this syndrome. In this study, we evaluated QT dispersion in PCOS patients without overt heart disease. Thirty-six consecutive women with PCOS (mean age 24+/-5 years) and 36 healthy women of similar ages (mean age 24+/-4 years) participated in this study. PCOS was diagnosed if there were polycystic ovaries by ultrasound (enlarged ovaries with > or =8 cysts 2-8 mm in diameter), oligoamenorrhea (intermenstrual interval >35 days), hirsutism (Ferriman-Gallwey score, > or =7) and elevated serum levels of testosterone (> or =2.7 nmol/L). Electrocardiograms were recorded at a paper speed of 50 mm/s. QT intervals were manually measured by a cardiologist. All intervals were corrected for heart rate according to Bazett's formula: QTc interval=QT interval/square root of the RR interval. Mean values of body mass index, heart rate, and blood pressure were not significantly different between the two groups (P>0.05). No significant differences in QT intervals (maximum QT, minimum QT, QT dispersion, minimum corrected QT, maximum corrected QT, and corrected QT dispersion) were observed between the two groups (P>0.05). Our results suggest that the risk of ventricular arrhythmias or sudden cardiac death is not increased in PCOS patients.     

The effects of tonsillectomy and adenoidectomy on pulmonary arterial pressure in children

PURPOSE: It is well known that hypertrophic tonsils and adenoids may cause upper-airway obstruction. The aim of this study is to determine the mean pulmonary arterial pressure (mPAP) in children with hypertrophic tonsils and adenoids and to clarify whether tonsillectomy and adenoidectomy (T&A) has any effect on mean pulmonary arterial pressure of these children. MATERIALS AND METHODS: Fifty-two randomly selected children (36 male, 16 female) aged between 4 and 11 (mean 7.7+/-2.5) a with a diagnosis of upper-airway obstruction resulting from hypertrophied tonsils and adenoids were included in our study. Thirty-three children were assigned as controls with similar age and sex distribution with the study groups. Mean pulmonary arterial pressure was measured by using Doppler echocardiography preoperatively and mean 5.4+/-2.9 months postoperatively in all subjects. RESULTS: When the mean pulmonary arterial pressure values of study and control group compared preoperatively, the mean pulmonary arterial pressure levels of the children in the study group were significantly higher than the mean pulmonary arterial pressure levels of the children in the control group (P<.05) (study group mean PAP=23.13+/-7.68, control group mean PAP=16.11+/-7.24) (Levene's test, P<.05). When the preoperative and postoperative results were compared, it was found that there was a statistically significant decrease in mean pulmonary arterial pressures in these 52 children (preoperative mean PAP=23.13+/-7.68, postoperative mean PAP=17.00+/-6.99) (paired sample t test, P<.05). Twenty-seven of the 52 subjects in the study group were pulmonary hypertensive preoperatively. mPAPs of 18 of these children decreased to normal range yielding 9 subjects, and this was also found ststistically significant (McNemar test, P<.001). CONCLUSION: This study showed that obstructive adenoid and tonsillar hypertrophy causes higher mPAP values in children and revealed that T&A is an effective therapeutic measure in such patients.     

Doppler echocardiographic evaluation of ventricular function in patients with rheumatoid arthritis

 Cardiac involvement in rheumatoid arthritis (RA) has been reported previously. However, evaluation of ventricular function in this disease by the use of recently proposed Doppler echocardiographic methods has not been reported before. Thus, the aim of this study was to evaluate ventricular function by measurement of myocardial performance index (MPI) and transmitral flow propagation velocity (TFPV). Thirty-two patients with long-standing RA and 32 control subjects (mean ages 52 ± 11 and 50 ± 10 years, respectively) participated in this study. Systolic function was assessed by subjective evaluation of wall motion for both ventricles and by fractional shortening for the left ventricle (LV). LV diastolic function was evaluated by standard pulsed-wave Doppler echocardiography, MPI and TFPV. Right ventricular (RV) function was evaluated by MPI. No subject had signs or symptoms of clinically overt heart failure. Systolic function was normal in all subjects. Among the echocardiographic indices of LV diastolic function the peak E velocity, E velocity/A velocity ratio, isovolumetric relaxation time, MPI and TFPV in the RA group were significantly different from those of the controls (P < 0.05). However, we did not observe a significant difference in RV echocardiographic indices between the two groups. Our results show that there is LV diastolic dysfunction in patients with long-standing RA. The lack of a history of cardiotoxic antirheumatic drug use among our patients suggests that this abnormality is due to RA itself. Received: 11 March 2002 / Accepted: 2 October 2002     

Single dose nasal 17beta-estradiol administration reduces sympathovagal balance to the heart in postmenopausal women

AIM: Long-term estrogen replacement therapy has favorable results on autonomic cardiovascular functions in postmenopausal women. Although acute estrogen administration has beneficial modulations on autonomic tone in animal studies, there are still controversies about the effects of acute estrogen on autonomic modulation to the heart in humans. The aim of this double-blind study was to investigate the acute effects of intranasal 17beta-estradiol administration on autonomic control of heart rate. METHODS: Nineteen postmenopausal women with typical hormone profiles were crossover randomized to 300 micro g nasal 17beta-estradiol (Aerodiol, Servier, Chambray-les-Tours, France) or an identical placebo at least 5 days apart. Both time domain and frequency domain heart rate variability (HRV) parameters were obtained during controlled respiration (CR) and handgrip exercise (HGE), before and 45 min after 17beta-estradiol or placebo administration. RESULTS: Baseline HRV parameters were similar for each occasion. Time domain indices obtained after 17beta-estradiol administration were not significantly different from results obtained with the placebo. In frequency domain parameters, 17beta-estradiol administration resulted in a reduced low frequency to high frequency ratio (LF/HF ratio) when compared with the placebo during CR (0.72 +/- 0.09 vs 1.00 +/- 0.15, P < 0.05) but not during HGE (3.03 +/- 0.37 vs 2.86 +/- 0.30, P > 0.05). CONCLUSION: A single intranasal 17beta-estradiol administration acutely reduced sympathovagal balance to the heart during the course of parasympathetic maneuver in healthy postmenopausal women.     

The radiological findings of COVID-19

Background/aimAvailable information on the radiological findings of the 2019 novel coronavirus disease (COVID-19) is constantly updated. Ground glass opacities (GGOs) and consolidation with bilateral and peripheral distribution have been reported as the most common CT findings, but less typical features can also be identified. According to the reported studies, SARS-CoV-2 infection is not limited to the respiratory system, and it can also affect other organs. Renal dysfunction, gastrointestinal complications, liver dysfunction, cardiac manifestations, and neurological abnormalities are among the reported extrapulmonary features. This review aims to provide updated information for radiologists and all clinicians to better understand the radiological manifestations of COVID-19.Materials and methodsRadiological findings observed in SARS-CoV-2 virus infections were explored in detail in PubMed and Google Scholar databases.ResultsThe typical pulmonary manifestations of COVID-19 pneumonia were determined as GGOs and accompanying consolidations that primarily involve the periphery of the bilateral lower lobes. The most common extrapulmonary findings were increased resistance to flow in the kidneys, thickening of vascular walls, fatty liver, pancreas, and heart inflammation findings. However, these findings were not specific and significantly overlapped those caused by other viral diseases, and therefore alternative diagnoses should be considered in patients with negative diagnostic tests. Conclusion Radiological imaging plays a supportive role in the care of patients with COVID-19. Both clinicians and radiologists need to know associated pulmonary and extrapulmonary findings and imaging features to help diagnose and manage the possible complications of the disease at an early stage. They should also be familiar with CT findings in patients with COVID-19 since the disease can be incidentally detected during imaging performed with other indications.