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
目的研究动态心电图(DCG)心率变异性(HRV)指标与急性脑卒中(ACA)心脏自主神经功能、预后的关系。方法选取我院2023年8月至2024年8月收治的ACA患者80例(包含43例脑梗死和37例脑出血)作为ACA组,并选择同期于我院就诊的非ACA患者80例作为非...目的研究动态心电图(DCG)心率变异性(HRV)指标与急性脑卒中(ACA)心脏自主神经功能、预后的关系。方法选取我院2023年8月至2024年8月收治的ACA患者80例(包含43例脑梗死和37例脑出血)作为ACA组,并选择同期于我院就诊的非ACA患者80例作为非ACA组。两组患者均进行DCG检查,并记录两组的HRV指标[窦性心律RR间期的标准差(SDNN)、每5 min RR间期标准差(SDANN)、窦性RR间期的平方根(rMSSD)、相邻RR间期互差>50 ms的心跳数所占分析信息期间内心搏数百分比(PNN50)]。比较ACA组和非ACA组、不同类型ACA患者的HRV指标,并随访12个月,分析不同预后患者的HRV指标。结果ACA组的SDNN、SDANN、rMSSD、PNN50水平均低于非ACA组(P<0.05)。脑梗死和脑出血患者的SDNN、SDANN、rMSSD、PNN50水平对比无显著差异(P>0.05)。生存患者的SDNN、SDANN、rMSSD、PNN50水平均高于死亡患者(P<0.05)。结论HRV指标能在一定程度上评估ACA患者的心脏自主神经功能和预后,临床针对ACA患者应及时使用DCG进行监测,计算HRV指标,以便后续开展针对性治疗,改善预后情况。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。
文摘目的研究动态心电图(DCG)心率变异性(HRV)指标与急性脑卒中(ACA)心脏自主神经功能、预后的关系。方法选取我院2023年8月至2024年8月收治的ACA患者80例(包含43例脑梗死和37例脑出血)作为ACA组,并选择同期于我院就诊的非ACA患者80例作为非ACA组。两组患者均进行DCG检查,并记录两组的HRV指标[窦性心律RR间期的标准差(SDNN)、每5 min RR间期标准差(SDANN)、窦性RR间期的平方根(rMSSD)、相邻RR间期互差>50 ms的心跳数所占分析信息期间内心搏数百分比(PNN50)]。比较ACA组和非ACA组、不同类型ACA患者的HRV指标,并随访12个月,分析不同预后患者的HRV指标。结果ACA组的SDNN、SDANN、rMSSD、PNN50水平均低于非ACA组(P<0.05)。脑梗死和脑出血患者的SDNN、SDANN、rMSSD、PNN50水平对比无显著差异(P>0.05)。生存患者的SDNN、SDANN、rMSSD、PNN50水平均高于死亡患者(P<0.05)。结论HRV指标能在一定程度上评估ACA患者的心脏自主神经功能和预后,临床针对ACA患者应及时使用DCG进行监测,计算HRV指标,以便后续开展针对性治疗,改善预后情况。
