Heartbeat-aware convolutional neural network for R-peak detection of wearable device ECG data / 南方医科大学学报

OBJECTIVE@#To develop a method for R-peak detection of ECG data from wearable devices to allow accurate estimation of the physiological parameters including heart rate and heart rate variability.@*METHODS@#A fully convolutional neural network was applied to predict the R-peak heatmap of ECG data and locate the R-peak positions. The heartbeat-aware (HA) module was introduced to enable the model to learn to predict the heartbeat number and R-peak heatmap simultaneously, thereby improving the capability of the model for extraction of the global context. The R-R interval estimated by the predicted heartbeat number was adopted to calculate the minimum horizontal distance for peak positioning. To achieve real-time R-peak detection on mobile devices, the deep separable convolution was adopted to reduce the number of parameters and the computational complexity of the model.@*RESULTS@#The proposed model was trained only with ECG data from wearable devices. At a tolerance window interval of 150 ms, the proposed method achieved R peak detection sensitivities of 100% for both wearable device ECG dataset and a public dataset (i.e. LUDB), and the true positivity rates exceeded 99.9%. As for the ECG signal of a 10 s duration, the CPU time of the proposed method for R-peak detection was about 23.2 ms.@*CONCLUSION@#The proposed method has good performance for R-peak detection of both wearable device ECG data and routine ECG data and also allows real-time R-peak detection of the ECG data.

Variabilidad de la frecuencia cardiaca en pacientes con cardiopatía chagásica / Heart rate variability in patients with Chagas' heart disease

RESUMEN Se estima la prevalencia por Trypanosoma cruzi de 436.000 habitantes en Colombia, con casos anuales de 5.250, en población expuesta de 4.792.000 habitantes. La variabilidad de la frecuencia cardiaca (VFC) es la variabilidad en el tiempo, de un latido cardiaco, medido en un análisis de periodo temporal determinado. Su análisis permite determinar el equilibrio simpático-vagal de manera indirecta. Este estudio analizó las variables temporales y No lineales, en 19 pacientes Chagásicos y 19 controles, utilizándose un polígrafo de alta resolución y el software Kubios. La variable Desviación Estandar del Intervalo RR (SDRR) en la población control arrojó un promedio de 56,23(29,6ms vs 40,62(30,1ms, en los seropositivos; La Raíz Cuadrada del Promedio de la Suma de las Diferencias al Cuadrado de todos los intervalos Adyacentes (RMSSD) fue de 34,31(21,01ms y 31,94(37,33ms, para controles y Chagas, respectivamente. El número de los intervalos RR consecutivos, que difieren en más de 50ms entre sí (NN50), en controles 76,47(78,3 latidos vs 13,47(36,8 para seropositivos, que correspondió con el porcentaje de NN50 (pNN50) 12,3(13,3% y 2,64(6,0%, respectivamente, para el mismo orden de los grupos. Valores de Entropía Aproximada (ApEn) fueron 1,249(0,134, para controles y 0,959(0,325, para seropositivos y para la Entropía Muestral (SampEn) fue de 1,358(0,264 y 1,102(0,385, para controles y chagásicos, respectivamente. Se encontró mayor irregularidad de HRV en controles, que es reflejo de un mejor estado de salud.

ABSTRACT The prevalence by Trypanosoma cruzi of 436,000 inhabitants in Colombia is estimated, with annual cases of 5,250, in an exposed population of 4,792,000 inhabitants. Heart rate variability (HRV) is the time interval of a beat in a given time analysis. Its analysis allows to determine the sympathetic-vagal balance indirectly. This study analyzed the temporal and non-linear variables in 19 Chagasic patients and 19 controls, using a high-resolution polygraph and the Kubios software. The variable Standard Deviation of the RR Interval (SDRR) in the control population showed an average of 56.23±29.6ms vs 40.62±30.1ms in the seropositive; The Square Root of the Sum of the Square Differences of all Adjacent intervals (RMSSD) was 34.31±21.01ms and 31.94±37.33ms for controls and Chagas respectively. The number of consecutive RR intervals that differ by more than 50ms from each other (NN50) in controls 76.47±78.3 beats vs 13.47±36.8 for seropositives corresponding to the percentage of NN50 (pNN50) 12.3±13.3% and 2.64±6.0%, respectively for the same order of the groups. Approximate Entropy (ApEn) values were 1,249±0,134 for controls and 0,959±0,325 for seropositive, and for Sample Entropy (SampEn) it was 1,358±0,264 and 1,102±0,385 for controls and chagasics respectively. Greater irregularity of HRV was found in controls, which reflects a better state of health.

Yolk sac count matters

Yolk sac is the first anatomical structure identified within the gestational sac at 5+ weeks and is diagnostic of intrauterine pregnancy. It is attached through the yolk stalk with the intestinal cavity of the embryo and is supplied with blood vessels that transport nutritive yolk products to the developing embryo. It provides nutritive, metabolic, endocrine, immunological and haemopoietic functions. The poor quality and early regression of a yolk sac in presence of embryonic heart beats are more specific than the large size of a yolk sac in predicting pregnancy loss. Number of yolk sac is usually indicative of amnionicity, except in select reported cases of monoamniotic twins when two yolk sacs are present. Singleton pregnancies contain only one yolk sac as a rule. We have come across a case of elderly non-diabetic primi gravida where presence of one extra yolk sac has accelerated growth of single foetus by 8 days in early first trimester. We followed it up to 16 weeks of gestation when both yolk sacs disappeared. It was concluded that two yolk sacs conferred extra mileage of growth to the foetus due to doubled yolk sac functions, and this extra growth persisted throughout.

Analyzing approaches to mathematic modeling of heart sounds

The article introduces the findings of the analysis of the existing approaches to the development of mathematical models of acoustic heart phenomena. The analysis of mathematical methods that can be used to model heart sounds has been performed with the use of reference signals from the 3M Open Library (Littmann Library) and a set of signals obtained by the authors during their previous scientific efforts. The analysis findings have allowed revealing the approaches and methods that are most suitable for developing the mathematical models of human phonocardiograms (normal and pathological) for further research efforts meant to develop methods to single out heart beats against the high level of interference and creating intervalograms to characterize the heart rate at the current moments of time. In addition to the generation of model phonocardiograms, the article reviews the methods to analyze model and real-life phonocardiograms with the assessment of an input from random and deterministic components.

The relationship study on alexithymia and interoception in patents with panic disorder / 中华行为医学与脑科学杂志

Objective To explore the characteristics of alexithymia and interoception in patients with panic disorder(PD) and its relationship. Methods Thirty-seven patients with PD and 45 healthy con-trols who met the diagnostic criteria of DSM-Ⅳ were selected. Toronto Alexithymia Scale ( TAS) and state-trait anxiety inventory ( STAI) were used to assess the characteristics of alexithymia and anxiety symptoms respectively. The heartbeat perception levels were tested by the Mental Tracking Paradigm. Results The de-tection rate of alexithymia in patients with panic disorder was 37. 83% (14/37),but the rate in the normal control group was only 4. 44%(2/45),and the difference was statistically significant (χ2=14. 42,P<0. 05). The total score of TAS (55. 11±10. 99),factor Ⅰ (20. 62±6. 78) and factor Ⅱ (14. 68±3. 70) in the PD group were higher than those in the control group (42. 93± 9. 25,12. 82± 4. 99,11. 42±3. 04; F=20. 72, 31. 08,15. 31,P<0. 01). The levels of the heartbeat perception were higher in the PD group than that in the control group (0. 75±0. 15,0. 58±0. 19;t=4. 13,P<0. 05). In PD group,the score of STAI were positively correlated with TAS total score and factor Ⅰ and Ⅱ scores( r=0. 57,0. 61,0. 47;r=0. 54,0. 62,0. 39,P<0. 05). There was no significant correlation between the scores of STAI and the level of interoception. The mediating effect of interoception level on alexithymia and state anxiety was not significant while the mediating effect on alexithymia and trait anxiety was also not significant. Conclusions The alexithymia detection rate and interoception sensitivity in patients with panic disorder were higher than those of healthy people. There may be interaction between alexithymia and anxiety symptoms. Interoception may be a clinical feature of panic disorder.

Comparison of the effect of two different ways of cardiopulmonary resuscitation during cardiac arrest / 中国基层医药

Objective To compare the effect of two different types of cardiopulmonary resuscitation (CPR)in cardiac arrest.Methods 150 patients with cardiac arrest were selected.The patients were divided into two groups according to the random number table method,each group in 75cases.The patients in the control group were treated with CPR.The patients in the observation group were treated with CPR machine.The body temperature,hemoglobin concentration,hematocrit,arterial blood gas analysis and resuscitation were compared between the two groups after 10min and 30min.Results There were no statistically significant differences in body temperature,hemoglobin and hematocrit between the control group and the observation group at 10min and 30min after CPR (t10min =1.44,2.01,1.23,t30min =1.69,1.81,1.02,all P ＞ 0.05).There were no statistically significant differences in PaCO2 between the two groups at 10 min and 30 min after resuscitation (t =1.54,1.02,all P ＞ 0.05).The arterial blood pH[(7.02 ±0.14)],PaO2 [(16.29 ± 4.38) kPa],HCO3 [(5.66 ± 1.73) kPa] and SaO2 [(0.84 ± 0.05) ％] of the control group recovered 30 min were significantly lower than recovered 10 min (t =7.14,6.55,6.20,7.03,all P ＜ 0.05).The arterial blood pH[(7.11 ± 0.1)],PaO2 [(18.36 ± 4.55) kPa],HCO3 [(6.34 ± 2.15) kPa],SaO2 [(0.86 ±0.04) ％] of the observation group recovered 30 min were significantly lower than recovered 10 min (t =6.75,6.21,6.01,6.60,all P ＜0.05).The arterial blood pH,PaO2,HCO3 and SaO2 of the observation group were significantly higher than those in the control group at 10 min and 30 min,the differences were statistically significant (t10min =6.03,7.34,7.88,6.10,t30min =6.21,8.20,7.10,6.11,all P ＜ 0.05).The effective rate of CPR in the observation group was 69.33％,which was significantly higher than 46.67％ in the control group,the difference was statistically significant (x2 =9.34,P ＜ 0.05).Conclusion Compared with artificial heart and lung resuscitation,CPR machine is more effective for patients with heartbeat respiratory arrest.It is more effective in cycling support and can improve the efficacy of CPR and is worthy of clinical application.

Técnicas de procesamiento de la señal ECGAR aplicadas en el prototipo DIGICARDIAC / Techniques HRECG signal processing applied at DIGICARDIAC prototype

Este artículo reporta el desarrollo de la etapa de procesamiento de la señal electrocardiográfica implementada en el prototipo DIGICARDIAC. El prototipo DIGICARDIAC es un instrumento de uso médico que permite la adquisición simultánea de las doce derivaciones del electrocardiograma (ECG) estándar, con características de alta resolución (ECGAR). El software desarrollado, pretende agrupar algunos de los criterios expuestos por los investigadores e implementar algunas técnicas novedosas, en la detección del latido cardiaco y la medición de los intervalos QT y ST en la señal ECGAR adquirida con el sistema. En las pruebas de funcionamiento se comprobó la eficiencia del algoritmo. Los errores obtenidos en la detección del complejo QRS son inferiores al 0,1 % y en la medición del intervalo QT se obtuvo un error promedio del 1,89 % en las señales ECG de los pacientes control.

This paper reports the development stage of the electrocardiographic signal processing implemented at the prototype DIGICARDIAC. The DIGICARDIAC prototype is a medical instrument that allows the simultaneous acquisition of the twelve-lead electrocardiogram (ECG) standard, which features high resolution (HRECG). The software developed, aims to bring together some of the criteria set up by the researchers and implement some new techniques, in heartbeat detection and measurement of QT and ST intervals in the HRECG signal acquired with the system. The algorithm efficient was proved through tests of perfomance. The errors obtained in QRS complex detection are lower than 0,1% and measuring QT interval averaging 1.89% error in the ECG signals of the control patients was obtained.

Peritoneal ventilation for oxygenation of asphyxia rabbits / 中华创伤杂志

Objective To observe the oxygenation and heartbeat duration effect of peritoneal ventilation with oxygen on a rabbit asphyxia model so as to provide a basis for treatment of severe respiratory damage with peritoneal oxygenation technique. Methods Twenty-four New Zealand rabbits were randomized into control group,air group and oxygen group,eight rabbits per group.Trachea dissection and intubation,carotid artery and vein catheter and placement of peritoneal cavity in and out of air duct were performed.An asphyxia model was built by clamping the tracheal catheter and was administered with peritoneal ventilation (with air in air group and oxygen in oxygen group).Indices including blood gas and mean arterial pressure (MAP) before and at an interval of one minute after asphyxia and heartbeat duration were observed,and their differences between groups were compared. Results The arterial partial pressure of oxygen ( PaO2 ) in the oxygen group was higher than that in the control group within four minutes after asphyxia.The partial pressure of carbon dioxide ( PaCO2 ) [ (77.6 ± 11.2) mm Hg] in the oxygen group was significantly lower than (89.1 ± 10.1 )mm Hg in the control group at four minutes after asphyxia.The heartbeat duration [ (6.48 ± 0.89 ) minutes ] in the oxygen group was longer than (5.03 ± 0.51 ) minutes in the control group.MAP had no obvious changes in the three groups. Conclusion The transperitoneal ventilation with gaseous oxygen can alleviate the decrease of PaO2,increase of PaCO2 and prolong the duration of heartbeat in an asphyxia rabbit model.

Clinical fixing of heartbeat machine to the expended myodcardium patient's double-heartroomsdouble-heartrooms / 医疗卫生装备

This paper presents the knowledge on fixing the heartbeat machine to the patients in such aspects as fixing,testing,using,notice in fixing,etc.

Signal preprocessing of non-contact life parameters detection by radar technology / 医疗卫生装备

This paper introduces the means and characteristics of signal acquisition of the non-contact life parameters detection system as well as the design of preprocessor circuit.The results show that the preprocessor is designed reasonably,which can provide the computer with high quality signals.