scholarly journals Predictors of the development of cardiac arrhythmias in women after induction of superovulation in vitro fertilization

2020 ◽  
Vol 10 (5) ◽  
pp. 57-65
Author(s):  
Victoria V. Vakareva ◽  
Marina V. Avdeeva ◽  
Larisa V. Scheglova ◽  
Sergey A. Bondarev ◽  
Pavel B. Voronkov
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Cardiovascular System ◽  
Functional State ◽  
Blood Pressure Monitoring ◽  
Myocardial Oxygen Demand ◽  
Heart Rate Variability Analysis ◽  
Supraventricular Arrhythmias ◽  
Rate Profile

The article presents the results of a clinical and instrumental examination of 80 healthy women (average age 32,313,57 years) in order to assess the heart rhythm disturbances after induction of superovulation duringin vitrofertilization. All women were examined twice before and after induction of superovulation during extracorporeal fertilization. Clinical and instrumental examination included: electrocardiography at rest; echocardiography; 24-hour ECG monitoring with heart rate variability analysis; 24-hour blood pressure monitoring. Induction of superovulation is associated with a significant increase in mean daily HR max (р0,01), and consequently with an increase in myocardial oxygen demand. It has been established that induction of superovulation contributes to the development of supraventricular arrhythmias (р0,01) and an increase in episodes of apnea/hypnea (р0,01). Regression analysis revealed predictors of supraventricular arrhythmias after induction of superovulation, including adverse circadian heart rate profile, adverse circadian blood pressure profile, impaired autonomic regulation of heart activity (р0,01). It was shown that the appearance of rhythm disturbances is associated with both the initial functional state of the cardiovascular system and its response to the induction of superovulation. It was established a correlation between the estradiol concentration and the increase of daily average heart rate after induction of superovulation (r=0,30,р0,05), apnea/hypnea index after induction of superovulation (r=0,34,р0,05). Conclusion. Superovulation induction may exacerbate existing chronic cardiovascular diseases. Due to the adverse effect of superovulation induction on the daily heart rate profile, women need to evaluate the functional state of the cardiovascular system duringinvitrofertilization planning. This will prepare the woman for the upcoming procedure and avoid adverse reactions from the cardiovascular system in response to stimulation of superovulationin vitrofertilization.

Bifurcation in a Simple Model of the Cardiovascular System

2000 ◽  
Vol 39 (02) ◽  
pp. 118-121 ◽  
Author(s):  
S. Akselrod ◽  
S. Eyal
Keyword(s):  
Nonlinear Dynamics ◽  
Blood Pressure ◽  
Heart Rate ◽  
Fixed Point ◽  
Cardiovascular System ◽  
Modified Model ◽  
Mayer Waves ◽  
Sustained Oscillations ◽  
Human Cardiovascular System ◽  
Physiological Values

Abstract:A simple nonlinear beat-to-beat model of the human cardiovascular system has been studied. The model, introduced by DeBoer et al. was a simplified linearized version. We present a modified model which allows to investigate the nonlinear dynamics of the cardiovascular system. We found that an increase in the -sympathetic gain, via a Hopf bifurcation, leads to sustained oscillations both in heart rate and blood pressure variables at about 0.1 Hz (Mayer waves). Similar oscillations were observed when increasing the -sympathetic gain or decreasing the vagal gain. Further changes of the gains, even beyond reasonable physiological values, did not reveal another bifurcation. The dynamics observed were thus either fixed point or limit cycle. Introducing respiration into the model showed entrainment between the respiration frequency and the Mayer waves.

The Involvement of Platelets and the Coronary Vasculature in Collagen-Induced Sudden Death in Rabbits

1985 ◽  
Vol 53 (01) ◽  
pp. 070-074 ◽  
Author(s):  
G Mallarkey ◽  
G M Smith
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Platelet Count ◽  
Sudden Death ◽  
Myocardial Ischaemia ◽  
Plasma Levels ◽  
Sodium Citrate ◽  
Plasma Samples ◽  
Calcium Entry Blockers

SummaryThe mechanism of collagen-induced sudden death in rabbits was studied by measuring blood pressure (BP), heart rate, ECG, the continuous platelet count and the plasma levels of thromboxane B2 (TxB2) and 6-keto prostaglandin Fia (6-keto PGF1α). Death was preceded by myocardial ischaemia and a sharp fall in BP which occurred before any fall in platelet count was observed. The calcium entry blockers (CEBs), verapamil, nifedipine and PY 108-068 protected the rabbits from sudden death without any significant effect on the decrease in the platelet count or increase in plasma TxB2 levels. 6-keto PGF1α could not be detected in any plasma samples. Indomethacin and tri-sodium citrate also protected the rabbits but significantly reduced the fall in platelet count and plasma TxB2. In vitro studies on isolated aortae indicated that verapamil non-specifically inhibited vasoconstriction induced by KC1, adrenaline and U46619 (a thromboxane agonist). It is concluded that CEBs physiologically antagonize the vasoconstricting actions of platelet-derived substances and that it is coronary vasoconstriction that is primarily the cause of death.

Cardiovascular Effects of Micromeria graeca (L.) Benth. ex Rchb in Normotensive and Hypertensive Rats

2020 ◽  
Vol 20 (8) ◽  
pp. 1253-1261
Author(s):  
Mourad Akdad ◽  
Mohamed Eddouks
Keyword(s):  
Blood Pressure ◽  
Cardiovascular System ◽  
Arterial Blood Pressure ◽  
Antihypertensive Activity ◽  
Computer Assisted ◽  
Hypertensive Rats ◽  
Vasorelaxant Effect ◽  
Arterial Blood

Aims: The present study was performed in order to analyze the antihypertensive activity of Micromeria graeca (L.) Benth. ex Rchb. Background: Micromeria graeca (L.) Benth. ex Rchb is an aromatic and medicinal plant belonging to the Lamiaceae family. This herb is used to treat various pathologies such as cardiovascular disorders. Meanwhile, its pharmacological effects on the cardiovascular system have not been studied. Objective: The present study aimed to evaluate the effect of aqueous extract of aerial parts of Micromeria graeca (AEMG) on the cardiovascular system in normotensive and hypertensive rats. Methods: In this study, the cardiovascular effect of AEMG was evaluated using in vivo and in vitro investigations. In order to assess the acute effect of AEMG on the cardiovascular system, anesthetized L-NAME-hypertensive and normotensive rats received AEMG (100 mg/kg) orally and arterial blood pressure parameters were monitored during six hours. In the sub-chronic study, rats were orally treated for one week, followed by blood pressure assessment during one week of treatment. Blood pressure was measured using a tail-cuff and a computer-assisted monitoring device. In the second experiment, isolated rat aortic ring pre-contracted with Epinephrine (EP) or KCl was used to assess the vasorelaxant effect of AEMG. Results: Oral administration of AEMG (100 mg/kg) provoked a decrease of arterial blood pressure parameters in hypertensive rats. In addition, AEMG induced a vasorelaxant effect in thoracic aortic rings pre-contracted with EP (10 μM) or KCl (80 mM). This effect was attenuated in the presence of propranolol and methylene blue. While in the presence of glibenclamide, L-NAME, nifedipine or Indomethacin, the vasorelaxant effect was not affected. Conclusion: This study showed that Micromeria graeca possesses a potent antihypertensive effect and relaxes the vascular smooth muscle through β-adrenergic and cGMP pathways.

Cardiovascular Responses to Muscle Stretching: A Systematic Review and Meta-analysis

2021 ◽  
Author(s):  
Ewan Thomas ◽  
Marianna Bellafiore ◽  
Ambra Gentile ◽  
Antonio Paoli ◽  
Antonio Palma ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Cardiovascular System ◽  
Vascular Function ◽  
Meta Analysis ◽  
Random Effect ◽  
Cardiovascular Responses ◽  
Qualitative Description ◽  
Cross Sectional ◽  
Quantitative Synthesis

AbstractThe aim of this study will be to review the current body of literature to understand the effects of stretching on the responses of the cardiovascular system. A literature search was performed using the following databases: Scopus, NLM Pubmed and ScienceDirect. Studies regarding the effects of stretching on responses of the cardiovascular system were investigated. Outcomes regarded heart rate(HR), blood pressure, pulse wave velocity (PWV of which baPWV for brachial-ankle and cfPWV for carotid-femoral waveforms), heart rate variability and endothelial vascular function. Subsequently, the effects of each outcome were quantitatively synthetized using meta-analytic synthesis with random-effect models. A total of 16 studies were considered eligible and included in the quantitative synthesis. Groups were also stratified according to cross-sectional or longitudinal stretching interventions. Quality assessment through the NHLBI tools observed a “fair-to-good” quality of the studies. The meta-analytic synthesis showed a significant effect of d=0.38 concerning HR, d=2.04 regarding baPWV and d=0.46 for cfPWV. Stretching significantly reduces arterial stiffness and HR. The qualitative description of the studies was also supported by the meta-analytic synthesis. No adverse effects were reported, after stretching, in patients affected by cardiovascular disease on blood pressure. There is a lack of studies regarding vascular adaptations to stretching.

Ambulatory Blood Pressure Recordings in Children and Adolescents

PEDIATRICS ◽  
1994 ◽  
Vol 94 (2) ◽  
pp. 180-184
Author(s):  
Gregory A. Harshfield ◽  
Bruce S. Alpert ◽  
Derrick A. Pulliam ◽  
Grant W. Somes ◽  
Dawn K. Wilson
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Systolic Blood Pressure ◽  
Ambulatory Blood Pressure ◽  
Reference Data ◽  
Blood Pressure Monitoring ◽  
Age Groups ◽  
Specific Reference ◽  
Pressure Monitoring ◽  
Black And White

Objective. To provide reference data for ambulatory blood pressure monitoring (ABPM) and to determine the influence of age, sex, and race on these values. Methods. ABPM was performed on 300 healthy, normotensive boys and girls between the ages of 10 and 18 years, including 160 boys and 140 girls, of whom 149 were white and 151 were black. Mean systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) while awake and during sleep were calculated for black and white boys and girls aged 10 to 12 years, 13 to 15 years, and 16 to 18 years. Results. Boys compared with girls 10 to 12 years of age had higher mean (±SD) SBP (115 ± 9 vs 112 ± 9 mm Hg; P < .01) and DBP (67 ± 7 vs 65 ± 5 mm Hg; P < .01) while awake. Boys compared to girls 13 to 15 years of age had higher SBP while awake (116 ± 11 vs 112 ± 8 mm Hg; P < .01). Boys compared with girls 16 to 18 years of age had higher SBP while awake (125 ± 12 vs 111 ± 9 mm Hg; P < .01) and during sleep (116 ± 11 vs 106 ± 9 mm Hg). Comparisons within sex showed similar changes with age for boys and girls. Blacks compared with whites 13 to 15 years of age had higher SBP during sleep (109 ± 11 vs 105 ± 10 mm Hg; P < .01), and blacks compared with whites 16 to 18 years of age had higher DBP during sleep (66 ± 7 vs 58 ± 6 mm Hg; P < .01). Comparisons across age groups within race showed that blacks 16 to 18 years of age had higher SBP during sleep than blacks 10 to 12 years of age (109 ± 11 vs 104 ± 10 mm Hg), and higher DBP during sleep (66 ± 7 mm Hg; P < .01) than blacks 10 to 12 years of age (61 ± 7 mm Hg; P < .01) and 13 to 15 years of age (61 ± 8; P < .01 mm Hg). The changes with age were not significant for white subjects. Conclusion. These results provide age-specific reference data for ABPM in youths. These values differ by sex (boys more than girls) and race (Blacks more than Whites).

scholarly journals Rhythmic Breath Holding and Its Effect on Arterial Blood Pressure and Its Correlation With Blood Gases

2020 ◽  
Author(s):  
Bharti Bhandari ◽  
Manisha Mavai ◽  
Yogendra Raj Singh ◽  
Bharati Mehta ◽  
Omlata Bhagat
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Cardiovascular System ◽  
Arterial Blood Pressure ◽  
Blood Gases ◽  
Total Power ◽  
Breath Holding ◽  
Single Episode ◽  
Arterial Blood ◽  
Maximum Inspiration

A single episode of breath-holding (BH) is known to elevate the blood pressure, and regular breathing exercise lowers the blood pressure. This prompted us to investigate how a series of BH epochs would affect the cardiovascular system. To observe arterial blood pressure (ABP) and heart rate (HR) changes associated with a series of “BH epochs” following maximum inspiration and maximum expiration and find the underlying mechanisms for the change by autonomic activity. Thirty-five healthy young adults were instructed to hold their breath repetitively, for 5 minutes, in two patterns, one following maximum inspiration and other following maximum expiration. ABP and ECG (for Heart Rate Variability) were continuously recorded at rest and during both the maneuvers. Capillary blood gases (BG) were zanalyzed at baseline and at the breakpoint of the last epoch of BH. ABP rose significantly at the breakpoint during both the maneuvers. No change in HR was observed. There was significant fall in PO2 from 94.7 (4.1) mmHg at baseline to 79.1 (9.0) mmHg during inspiratory and 76.90 (12.1) mmHg during expiratory BH. Similarly, SPO2 decreased from 96.3 (1.9) % at baseline to 95.4 (1.5) % and 94.5 (2.7) % during inspiratory and expiratory BH, respectively. Rise in PCO2 from 39.5(3.1) mmHg at baseline to 42.9 (2.7) mmHg and 42.1 (2.8) mmHg during inspiratory and expiratory BH respectively was observed. There was no significant correlation between blood gases and arterial blood pressure. Among HRV parameters, a significant decrease in SDNN, RMSSD, HFnu, total power and SD1/SD2 and the significant increase in LFnu, LF/HF and SD2 were observed during both BH patterns. Rhythmic BH patterns affect the cardiovascular system in similar way as a single episode of BH. Sympathetic overactivity could be the postulated mechanism for the same. © 2019 Tehran University of Medical Sciences. All rights reserved. Acta Med Iran 2019;57(8):492-498.

Implantable and self-powered blood pressure monitoring based on a piezoelectric thinfilm: Simulated, in vitro and in vivo studies

Nano Energy ◽  
2016 ◽  
Vol 22 ◽  
pp. 453-460 ◽  
Author(s):  
Xiaoliang Cheng ◽  
Xiang Xue ◽  
Ye Ma ◽  
Mengdi Han ◽  
Wei Zhang ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Blood Pressure Monitoring ◽  
In Vivo Studies ◽  
Pressure Monitoring ◽  
Self Powered
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