The Karvonen formula, which is widely used to estimate exercise intensity, contains maximum heart rate, H Rmax, as a variable. This study employed pedaling experiments to assess which of the proposed formulas for calc...The Karvonen formula, which is widely used to estimate exercise intensity, contains maximum heart rate, H Rmax, as a variable. This study employed pedaling experiments to assess which of the proposed formulas for calculating H Rmaxwas the most suitable for use with the Karvonen formula. First, two kinds of experiments involving an ergometer were performed: an all-in-one-day experiment that tested eight pedaling loads in one day, and a one-load-per-day experiment that tested one load per day for eight days.A comparison of the data on 7 subjects showed that the all-in-one-day type of experiment was better for assessing H Rmaxformulas,at least for the load levels tested in our experiments. A statistical analysis of the experimental data on 47 subjects showed two of the H Rmaxformulas to be suitable for use in the Karvonen formula to estimate exercise intensity for males in their 20 s. In addition, the physical characteristics of a person having the greatest impact on exercise intensity were determined.展开更多
Aim:Myasthenia gravis(MG)is a neuromuscular transmission disorder caused by acetylcholine receptor autoantibodies.Cardiac autonomic dysfunctions were rarely reported in patients with MG.Functional cardiac abnormalitie...Aim:Myasthenia gravis(MG)is a neuromuscular transmission disorder caused by acetylcholine receptor autoantibodies.Cardiac autonomic dysfunctions were rarely reported in patients with MG.Functional cardiac abnormalities were variable and reported in patients at severe stages of the disease and with thymoma.We investigated cardiac functions in patients with MG using Ambulatory 24‑h electrocardiographic Holter‑Monitoring.Methods:This study included 20 patients with MG with a mean age of 28.45±8.89 years and duration of illness of 3.52±1.15 years.The standard Holter reports include data for heart‑rate,ventricular ectopies(VEs),supraventricular ectopies(SVEs),heart-rate variability(HRV),ST,QT,atrial fibrillation and T‑wave alternans.Results:VEs,SVEs and ST‑T changes were reported in 55%,40%and 20%of patients respectively.Compared with healthy subjects(n=20),HRV components including SDNN,SDANN,SDNN Index,RMS‑SD and pNN50(P=0.001 for all)were reduced in patients indicating sympathetic and parasympathetic autonomic dysfunctions.HRV abnormalities were reported in 30-60%of patients.No significant correlations were identified between SDNN,RMS‑SD,pNN50,and duration of illness.Conclusion:Depressed HRV may be an early manifestation of autonomic neuropathy in patients with MG even in milder stages of the disease.This information is useful in rating disease progression and the efficacy of therapeutic interventions.展开更多
目的探讨基于24 h动态心电图及动态血压监测对原发性高血压患者心房颤动(atrial fibrillation,AF)发生风险的预测价值。方法回顾性分析2021年3月至2024年3月郑州市第七人民医院心内科就诊的原发性高血压患者170例,根据诊断分为AF组38例,...目的探讨基于24 h动态心电图及动态血压监测对原发性高血压患者心房颤动(atrial fibrillation,AF)发生风险的预测价值。方法回顾性分析2021年3月至2024年3月郑州市第七人民医院心内科就诊的原发性高血压患者170例,根据诊断分为AF组38例,非AF组132例。通过24 h动态心电图和动态血压监测获取心率变异性(heart rate variability,HRV)和血压变异性(blood pressure variability,BPV)指标,包括24 h全部正常窦性心搏间期的标准差(24-hour standard deviation of normal-to-normal intervals,24 h SDNN)、每5 min节段SDNN的平均值(standard deviation of normal-to-normal intervals index,SDNN指数)、每5 min节段平均正常窦性心搏间期的标准差(standard deviation of the average normal-to-normal intervals index,SDANN指数)、相邻正常窦性心搏间期差值的均方根(root mean square of successive differencesr,rMSSD)、24 h收缩压标准差(24-hour systolic blood pressure standard deviation,24 h-SSD)、24 h舒张压标准差(24-hour diastolic blood pressure standard deviation,24 h-DSD)、24 h收缩压变异系数(24-hour systolic blood pressure coefficient of variation,24 h-SCV)。结果AF组24 h SDNN、SDNN指数、SDANN指数、rMSSD明显低于非AF组,24 h-SSD、24 h-DSD、24 h-SCV明显高于非AF组,差异有统计学意义(P<0.01)。24 h SDNN、SDNN指数、SDANN指数和rMSSD为AF发生的保护因素,24 h-SSD、24 h-DSD和24 h-SCV为AF发生的危险因素(P<0.01)。HRV+BPV指标预测的ROC曲线下面积为0.971(95%CI:0.911~0.995)。结论24 h动态心电图联合动态血压监测可有效预测原发性高血压患者AF发生风险。展开更多
基金supported by Health Science Center Foundation,Japan
文摘The Karvonen formula, which is widely used to estimate exercise intensity, contains maximum heart rate, H Rmax, as a variable. This study employed pedaling experiments to assess which of the proposed formulas for calculating H Rmaxwas the most suitable for use with the Karvonen formula. First, two kinds of experiments involving an ergometer were performed: an all-in-one-day experiment that tested eight pedaling loads in one day, and a one-load-per-day experiment that tested one load per day for eight days.A comparison of the data on 7 subjects showed that the all-in-one-day type of experiment was better for assessing H Rmaxformulas,at least for the load levels tested in our experiments. A statistical analysis of the experimental data on 47 subjects showed two of the H Rmaxformulas to be suitable for use in the Karvonen formula to estimate exercise intensity for males in their 20 s. In addition, the physical characteristics of a person having the greatest impact on exercise intensity were determined.
文摘Aim:Myasthenia gravis(MG)is a neuromuscular transmission disorder caused by acetylcholine receptor autoantibodies.Cardiac autonomic dysfunctions were rarely reported in patients with MG.Functional cardiac abnormalities were variable and reported in patients at severe stages of the disease and with thymoma.We investigated cardiac functions in patients with MG using Ambulatory 24‑h electrocardiographic Holter‑Monitoring.Methods:This study included 20 patients with MG with a mean age of 28.45±8.89 years and duration of illness of 3.52±1.15 years.The standard Holter reports include data for heart‑rate,ventricular ectopies(VEs),supraventricular ectopies(SVEs),heart-rate variability(HRV),ST,QT,atrial fibrillation and T‑wave alternans.Results:VEs,SVEs and ST‑T changes were reported in 55%,40%and 20%of patients respectively.Compared with healthy subjects(n=20),HRV components including SDNN,SDANN,SDNN Index,RMS‑SD and pNN50(P=0.001 for all)were reduced in patients indicating sympathetic and parasympathetic autonomic dysfunctions.HRV abnormalities were reported in 30-60%of patients.No significant correlations were identified between SDNN,RMS‑SD,pNN50,and duration of illness.Conclusion:Depressed HRV may be an early manifestation of autonomic neuropathy in patients with MG even in milder stages of the disease.This information is useful in rating disease progression and the efficacy of therapeutic interventions.
文摘目的:带状疱疹后神经痛(postherpetic neuralgia,PHN)是一种带状疱疹老年患者严重而痛苦的并发症,与高交感神经活动有关,通过脊髓电刺激(spinal cord stimulation,SCS)置入可有效缓解PHN。近年来,心率变异性(heart rate variability,HRV)分析作为自主神经系统(autonomic nervous system,ANS)可靠、客观的反馈指标,被广泛应用于慢性疼痛的评估中。本研究旨在探讨SCS置入对PHN患者HRV的临床影响及其与疼痛结局的相关性。方法:回顾性选取2023年11月至2024年3月在中南大学湘雅三医院疼痛科符合纳入标准的患者28例。所有患者均接受SCS置入治疗,获取SCS置入前后的HRV数据,包括连续24 h所有正常至正常(心搏)间隔的标准差(standard deviation of normal-to-normal intervals,SDNN)、差值的均方根(root mean square of successive interval differences,RMSSD)、差值的标准差(standard deviation of successive differences,SDSD)、相邻R-R间期差值>50 ms的个数所占百分比(percentage of adjacent normal-to-normal intervals that differ by more than 50 milliseconds, PNN50)、低频段功率(low-frequency power, LF)、高频段功率(high-frequency power, HF)、 LF和HF比值(LF/HF)及5 min内所有频率总功率(total power,TP)。采用单因素线性回归分析探讨SCS治疗前后HRV指标的相关性。结果:SCS置入后,患者的HRV时域指标SDNN、RMSSD、SDSD、PNN50及频域指标LF、HF、TP均显著增加(均P<0.05),LF/HF值的变化差异无统计学意义(P>0.05)。SCS治疗对疼痛缓解、负面情绪改善、精神压力下降均有积极作用(均P<0.05)。不同节段SCS置入存在差异,胸椎T8以下节段置入SCS后患者的SDNN、LF、HF显著降低(均P<0.05)。相关性分析显示,患者疼痛评分与SDNN具有显著相关性,HRV时域指标SDSD、RMSSD、PNN50间存在显著相关性(均P<0.05),频域指标间相关性较低,且HRV时域与频域指标的变化呈协同促进趋势。结论:PHN患者疼痛结局与自主神经活动存在同步变化,SCS置入可改善PHN患者的HRV稳定性,有利于心脏节律的稳定。HRV测量可作为PHN患者ANS活动的证据。
文摘目的探讨基于24 h动态心电图及动态血压监测对原发性高血压患者心房颤动(atrial fibrillation,AF)发生风险的预测价值。方法回顾性分析2021年3月至2024年3月郑州市第七人民医院心内科就诊的原发性高血压患者170例,根据诊断分为AF组38例,非AF组132例。通过24 h动态心电图和动态血压监测获取心率变异性(heart rate variability,HRV)和血压变异性(blood pressure variability,BPV)指标,包括24 h全部正常窦性心搏间期的标准差(24-hour standard deviation of normal-to-normal intervals,24 h SDNN)、每5 min节段SDNN的平均值(standard deviation of normal-to-normal intervals index,SDNN指数)、每5 min节段平均正常窦性心搏间期的标准差(standard deviation of the average normal-to-normal intervals index,SDANN指数)、相邻正常窦性心搏间期差值的均方根(root mean square of successive differencesr,rMSSD)、24 h收缩压标准差(24-hour systolic blood pressure standard deviation,24 h-SSD)、24 h舒张压标准差(24-hour diastolic blood pressure standard deviation,24 h-DSD)、24 h收缩压变异系数(24-hour systolic blood pressure coefficient of variation,24 h-SCV)。结果AF组24 h SDNN、SDNN指数、SDANN指数、rMSSD明显低于非AF组,24 h-SSD、24 h-DSD、24 h-SCV明显高于非AF组,差异有统计学意义(P<0.01)。24 h SDNN、SDNN指数、SDANN指数和rMSSD为AF发生的保护因素,24 h-SSD、24 h-DSD和24 h-SCV为AF发生的危险因素(P<0.01)。HRV+BPV指标预测的ROC曲线下面积为0.971(95%CI:0.911~0.995)。结论24 h动态心电图联合动态血压监测可有效预测原发性高血压患者AF发生风险。
