Are "pink puffers" more breathless than "blue bloaters"?

Breathlessness, disability, and exercise tolerance were assessed in 26 patients with severe chronic airflow limitation (forced expiratory volume in one second (FEV1) less than or equal to 1 litre) divided into two groups--15 patients who were normocapnic (pressure of arterial carbon dioxide (Paco2) less than 5.5 kPa (less than 41.4 mm Hg)), and 11 patients who were hypercapnic (Paco2 greater than 6 kPa (greater than than 45.1 mm Hg)). The two groups were well matched for spirometric values (FEV1 0.59 1 and 0.62 1, respectively). All of the hypercapnic patients could improve blood gas tensions towards normal by hyperventilation. There were no significant differences in visual analogue scores of breathlessness during treadmill exercise, disability (oxygen-cost diagram, dyspnoea grade), or exercise tolerance (six-minute walk, maximal consumption of oxygen during bicycle ergometry, distance walked to exhaustion in progressive treadmill test). The findings show that the "fight" to maintain normal blood gas tensions in the face of severe airflow limitation does not have an appreciable cost in terms of disability.     

双心室起搏对慢性心力衰竭患者心肺功能的影响

目的　观察双心室起搏对慢性心力衰竭患者心肺功能的影响。方法　慢性心力衰竭伴室内传导阻滞患者 9例 ,全部植入三腔双心室起搏器 ,比较双心室起搏前后患者超声心动图、心肺功能的变化。结果　双心室同步起搏后 ,患者左室射血分数由术前 (2 1.6± 6 .7) %增加到 (2 7.3± 5 .2 ) % (术后 3月 ,P <0 .0 5 )、(2 9.5± 5 .4 ) % (术后 6月 ,P <0 .0 5 ) ,6分钟步行距离由术前 (32 0± 97)m增加到 (384± 10 3)m(术后 3月 ,P <0 .0 1)、(4 13± 110 )m(术后 6月 ,P <0 .0 1) ,峰值氧耗量、摄氧效率斜率及每分通气量 /每分二氧化碳产生量斜率较术前均有显著增加。生活质量评分分别改善 30 % (术后 3月 ,P <0 .0 1)、2 8% (术后 6月 ,P <0 .0 1)。结论　双心室起搏能有效改善慢性心衰患者心肺功能 ,增加运动能量 ,提高生活质量     

常规剂量氨茶碱对中老年人运动能力和氧耗量的影响

探讨静脉注射常规剂量氨茶碱对正常中老年人运动肺功能的影响。方法１４例正常中老年人分别于静脉注射０．２５ｇ氨茶碱前后，作症状限制性运动肺功能检查。结果氨茶碱能显著增加静息时分时通气量，呼吸频率及心率，但对运动能力和最大运动负荷时的分时通气量、氧耗量和通气方式等均不产生明显的影响。     

轻度贫血对学龄儿童体力工作能力的影响

本文报告29对轻度贫血和非贫血儿童在平板机运动试验条件下的最大运动耐受时间,耗氧量、心率和运动后血乳酸浓度。结果表明,轻度贫血组儿童最大耐受时间、最大耗氧量均低于非贫血组。运动后血乳酸高于非贫血组。经一个月补铁治疗后,贫血组最大耐受时间提高0.9分钟,血乳酸降至非贫血组水平,但最大耗氧量无显著性变化。由此说明轻度贫血对学龄儿童体力工作能力有一定的影响。     

冠状动脉慢血流患者运动实验后心率恢复分析

目的探讨冠状动脉慢血流(CSFP)患者在运动负荷实验后3min内的心率恢复(HRR)变化及意义。方法选取42例CSFP患者(CSFP组)及26名健康者(对照组),均进行心电图运动负荷试验,记录静息心率、峰值心率及运动后3min内的心率,计算运动停止后1、2、3min时的心率与运动中峰值心率的绝对差值(分别为HRR1、HRR2、HRR3),及心率恢复的校正值(HRR1%、HRR2%、HRR3%)。结果两组间静息心率、峰值心率、心率储备、预测储备心率、HRR2、HRR2%、HRR3、HRR3%及代谢当量(METs)、运动时间的差异均无统计学意义(P值均>0.05)。CSFP组的HRR1、HRR1%均显著低于对照组(P值均<0.01)。结论 CSFP患者HRR较健康者降低,推测此类患者存在自主神经调节异常的早期改变。     

Exercise-induced bronchoconstriction in adults with asthma--comparison between running and cycling and between cycling at different air conditions

The bronchial response to cycling and running was compared in six adult asthmatic persons. The effects of different air conditions during cycling regarding the induction of bronchoconstriction was studied. The exercise consisted of 6 minutes' work at an intensity of 80-85% of maximal heart rate. Heart rate, oxygen consumption and ventilation were measured to check that the exercise level was the same in all tests. Peak expiratory flow (PEF) was used to test for bronchoconstriction. Bicycling and treadmill running were performed under indoor conditions and bicycling while breathing cold, dry air (-18 degrees C) and room-tempered humid air (60% RH), respectively. No difference in bronchoconstriction was found between cycling and running under indoor conditions. However, bicycling exercise with inhalation of cold dry air provoked more bronchoconstriction than when inhalating humid air (PEF reductions of 19.4+/-6% and 6.1+/-2%, respectively). No differences were found between the exercise modes in heart rate, oxygen consumption, ventilation per minute, respiratory rate, carbon dioxide elimination or subjective ratings of perceived exertion and breathlessness. It is concluded that it is not the type of exercise, but the ventilation demand and humidity of the inspired air that are the main determinants of the occurrence and degree of bronchoconstriction.     

The 6-minute walk: a new measure of exercise capacity in patients with chronic heart failure

Cycle and treadmill exercise tests are unsuitable for elderly, frail and severely limited patients with heart failure and may not reflect capacity to undertake day-to-day activities. Walking tests have proved useful as measures of outcome for patients with chronic lung disease. To investigate the potential value of the 6-minute walk as an objective measure of exercise capacity in patients with chronic heart failure, the test was administered six times over 12 weeks to 18 patients with chronic heart failure and 25 with chronic lung disease. The subjects also underwent cycle ergometer testing, and their functional status was evaluated by means of conventional measures. The walking test proved highly acceptable to the patients, and stable, reproducible results were achieved after the first two walks. The results correlated with the conventional measures of functional status and exercise capacity. The authors conclude that the 6-minute walk is a useful measure of functional exercise capacity and a suitable measure of outcome for clinical trials in patients with chronic heart failure.     

平板运动试验时QTc离散度变化的分析

目的分析平板运动试验所致心肌缺血时QTc离散度(QTcd)的变化.方法观测207例平板运动试验阳性患者的运动前、运动中2 min、4 min、6 min及运动后2 min、4 min的QTcd并与200例运动试验阴性患者作比较.结果平板运动试验阳性组运动中、运动后QTcd值均明显增大,与阴性组比较有显著差异(P＜0.001);而运动试验阴性组运动前后QTcd变化小(P＞0.05).同时,运动试验阳性组心律失常发生率增高(40.09%),伴随症状增多(29.95%).结论通过平板运动试验观测QTcd变化,可作为评价冠心病的一项可靠、易行指标.     

6分钟步行试验的运动强度和临床应用价值研究

目的：研究6分钟步行试验中的运动强度,并探讨其临床应用价值。方法：16名志愿者先进行6分钟步行试验（6MWT）,测量每位受试者的6分钟步行距离（D）、做功（W）和结束时的摄氧量（VO2-6MWT）,再按Bruce方案进行极量心肺运动试验（ CPET）,检测每位受试者极量运动时的峰值摄氧量（ VO2-peak）和无氧阈（ AT）,CPET和6 MWT均采用便携式K4 B2气体分析仪实时检测气体交换参数,以获得 VO2-6 MWT、VO2-peak 和 AT。结果：（1）6MWT中16名受试者的摄氧量由运动初始的8．15ml上升到28．42ml,前1分钟上升较快,后5分钟基本进入平台期。（2）6分钟步行距离（6MWD）与6MWT结束时的摄氧量（ VO2-6MWT）成线性正相关;而VO2-6MWT与 CPET测得的AT无统计学差异。结论：对于健康受试者来说,6 MWT是无氧阈水平的运动试验,它能够反映受试者日常生活活动能力,也可能反映其有氧运动能力。     

运动试验心率快速增加与冠状动脉病变分析

目的探讨活动平板运动试验早期心率快速增加与冠状动脉病变的关系。方法选择临床拟诊冠心病患者340例,2周内进行活动平板运动试验与冠状动脉造影检查,根据冠状动脉造影结果分为冠心病组和非冠心病组者,与活动平板运动试验开始后的运动15秒心率、第1分钟心率增加量对照分析。结果冠心病组运动15秒心率、第1分钟心率明显高于非冠心病组（P〈0.01）;随着冠状动脉病变严重程度的增加,运动15秒心率、第1分钟心率逐渐增大,组间比较差异均有统计学意义（P〈0.01）;相关性分析显示运动15秒心率、第1分钟心率与ST段压低值及冠状动脉病变严重程度均呈正相关;运动最大代谢当量与ST段压低及冠状动脉病变严重程度呈负相关。结论冠心病患者运动15秒心率及第1分钟心率增大可反映心肌缺血及冠状动脉病变程度。     

外周动脉疾病患者踏车运动干预疗效的临床研究

目的:研究踏车运动对外周动脉疾病(peripheral arterial disease,PAD)患者功能恢复及远期预后的影响。方法:选取2010年5月~2011年4月于我院(50例)、遵义医学院附属医院(30例)、湖南省湘乡市人民医院(40例)心血管内科就诊的PAD患者共120例,并将其随机分为研究组和对照组。研究组实施6个月踏车运动运动干预,对照组则不接受,并分别于开始前及结束后记录踏车运动表现以及肱动脉流量介导的血管内皮功能等指标,其它PAD常规药物治疗两组相同。结果:(1)实施踏车运动干预6个月后,与对照组相比:研究组6分钟步行距离有显著增加(P<0.01);患者能够耐受的最长踏车时间及距离显著增加(P<0.01);肱动脉血流介导内皮舒张功能(FMD)显著改善(P<0.01)。结论:踏车运动干预可增加6分钟步行距离;延长最长踏车时间和距离;改善肱动脉血流介导的血管内皮功能。     

平板运动试验诱发心律失常的特点及对原有心律失常的影响

目的探讨平板运动试验诱发心律失常的特点,以及对原有心律失常的影响。方法对4643例患者应用标准Bruce方案进行次极量平板运动试验,同步监测血压和12导联心电图,记录运动前、运动中及恢复期的血压和心电图。结果运动前原有心律失常176例,运动诱发心律失常504例。心律失常的发生与性别无关(P=0.318),运动试验阳性者心律失常发生率(20.8%)明显高于阴性者(13.8%),P<0.001。在运动中发生的心律失常多于恢复期,但无统计学意义(P>0.05)。运动前原有心律失常在运动中消失的比例室性心律失常(66.7%)明显多于房性心律失常(34.0%),P=0.002;而运动诱发的房性和室性心律失常多在恢复期消失(分别为73.08%和66.47%)。结论运动诱发的心律失常以室性心律失常最为常见,且大多可在恢复期消失,因此应高度重视恢复期的心电监测(至少10min)。     

无氧代谢阈值在心功能评价中的应用

４３例健康人和１７５例心脏病患者作心－肺运动试验，以评价心功能不全的程度。采用自行车运动递增负荷试验，通过监测每分钟换气量（ＶＥ）、氧摄取量（ＶＯ２）和二氧化碳排出量（ＶＣＯ２）来确定无氧代谢阈值（ＡＴ）。同时也测定峰值ＶＯ２（ＰＶＯ２）和％ＡＴ。ＡＴ［ｍｌ／（ｍｉｎ·ｋｇ）］和ＰＶＯ２［ｍｌ／（ｍｉｎ·ｋｇ）］随年龄增大而下降，男性上述值均高于女性。％ＡＴ值（从年龄和性别预测的ＡＴ值经校正后的ＡＴ百分数）在心功能不全组随ＮＹＨＡ级别增高而降低；心功能Ⅰ、Ⅱ、Ⅲ级分别为８５．３％±１０．３％、７４．７％±１４．１％和５８．８％±１２．８％。１２例间隔３ｈ所测ＡＴ值重复性好（ｒ＝０．８５）。结果表明，心－肺运动试验的指标，特别是ＡＴ可以用作评价心功能不全的客观指标及其心功能不全治疗的效果。     

运动试验早期心率快速增加的临床意义

目的:探讨心电图平板运动试验早期心率的快速增加与冠状动脉(冠脉)病变的关系.方法:选择245例进行了心电图平板运动试验与冠状动脉造影的胸痛患者,根据冠脉造影结果,分为冠心病组和非冠心病组,冠心病组中又进一步分为单支病变、双支病变及三支病变组,对比分析各组平板运动试验开始后第1分钟心率的增加量(AHR1ninute).结果:冠心病组AHR1ninute明显高于非冠心病组(P＜0.01);随着冠脉病变严重度的增加AHR1ninute逐渐增大,组间差异均有显著性(P＜0.05);相关分析显示AHR1ninute与ST段压低值及冠脉病变严重度均呈正相关(r=0.252,0.470,P＜0.01).结论:冠心病患者AHR1ninute增大,△AHR1ninute可作为反映心肌缺血及冠脉病变程度的指标之一.     

Transcutaneous oxygen tension during exercise in patients with claudication

Transcutaneous oxygen tension (TcPO2) was monitored during maximal exercise in 10 patients with stable moderate to severe claudication. The TcPO2 fell by 16% at the onset of claudication and 32% at the maximum walking distance. On resting this decrease reached a maximum of 66% roughly four minutes after exercise. This was followed by a steady recovery. The percentage changes were reproducible in each patient and were appreciably different from the TcPO2 exercise profiles of normal healthy volunteers. TcPO2 monitoring during exercise is a simple, reproducible, cheap, and useful technique for assessing claudication and compares favourably with other techniques used to quantify this condition.     

Heart rate recovery and treadmill exercise score as predictors of mortality in patients referred for exercise ECG

CONTEXT: Both attenuated heart rate recovery following exercise and the Duke treadmill exercise score have been demonstrated to be independent predictors of mortality, but their prognostic value relative to each other has not been studied. OBJECTIVE: To assess the associations among abnormal heart rate recovery, treadmill exercise score, and death in patients referred specifically for exercise electrocardiography. DESIGN AND SETTING: Prospective cohort study conducted in an academic medical center between September 1990 and December 1997, with a median follow-up of 5.2 years. PATIENTS: A total of 9454 consecutive patients (mean [SD] age, 53 [11] years; 78% male) who underwent symptom-limited exercise electrocardiographic testing. Exclusion criteria included age younger than 30 years, history of heart failure or valvular disease, pacemaker implantation, and uninterpretable electrocardiograms. MAIN OUTCOME MEASURES: All-cause mortality, as predicted by abnormal heart rate recovery, defined as failure of heart rate to decrease by more than 12/min during the first minute after peak exercise, and by treadmill exercise score, defined as (exercise time) - (5 x maximum ST-segment deviation) - (4 x treadmill angina index). RESULTS: Three hundred twelve deaths occurred in the cohort. Abnormal heart rate recovery and intermediate- or high-risk treadmill exercise score were present in 20% (n = 1852) and 21% (n = 1996) of patients, respectively. In univariate analyses, death was predicted by both abnormal heart rate recovery (8% vs 2% in patients with normal heart rate recovery; hazard ratio [HR], 4.16; 95% confidence interval [CI], 3.33-5.19; chi(2) = 158; P<.001) and intermediate- or high-risk treadmill exercise score (8% vs 2% in patients with low-risk scores; HR, 4.28; 95% CI, 3.43-5.35; chi(2) = 164; P<.001). After adjusting for age, sex, standard cardiovascular risk factors, medication use, and other potential confounders, abnormal heart rate recovery remained predictive of death (among the 8549 patients not taking beta-blockers, adjusted HR, 2.13; 95% CI, 1.63-2.78; P<.001), as did intermediate- or high-risk treadmill exercise score (adjusted HR, 1. 49; 95% CI, 1.15-1.92; P =.002). There was no interaction between these 2 predictors. CONCLUSIONS: In this cohort of patients referred specifically for exercise electrocardiography, both abnormal heart rate recovery and treadmill exercise score were independent predictors of mortality. Heart rate recovery appears to provide additional prognostic information to the established treadmill exercise score and should be considered for routine incorporation into exercise test interpretation. JAMA. 2000;284:1392-1398.     

曲美他嗪对慢性心力衰竭患者血浆N-端脑利钠肽前体的影响及疗效观察

目的评价曲美他嗪对慢性心力衰竭患者血浆N-端脑利钠肽前体（yr—proBNP）的影响及疗效。方法将78例慢性心力衰竭患者随机分为两组。治疗组在常规组的基础上加曲美他嗪治疗。观察两组临床疗效、治疗前后血浆NT—proBNP浓度和6分钟步行试验（6MWr）。结果治疗组疗效明显优于常规组（P〈0．05）。与治疗前比较,治疗组血浆NT—proBNP下降幅度和6MWT上升幅度大于常规组,有显著性差异（P〈O．05）。结论曲美他嗪能降低慢性心力衰竭患者血浆NT-proBNP浓度,改善患者心功能,提高患者运动耐力和生存质量,值得临床推广。     

间质性肺疾病患者运动能力及运动时呼吸困难评价研究

目的探索间质性肺疾病(ILD)患者的运动负荷表现,为临床上应用运动负荷试验判定间质性肺疾病患者的预后和生活质量评价等提供理论依据。方法对36例间质性肺疾病患者和20位正常人进行了静态肺功能检查和运动负荷试验,测定了每分钟氧摄取量(VO2)、血氧饱和度(SpO2)和呼吸困难勃氏分级指数(BS)等指标。结果ILD患者与正常人比较明显运动中和最大运动时BS增加,SpO2明显下降,ILD患者VO2max小于正常人。结论ILD患者最大运动能力降低,运动中发生低氧血症,呼吸困难明显是主要运动限制因素。     

食管心房调搏心脏负荷试验QT离散度对冠心病的诊断价值

目的: 研究QT离散度(QTd)在食管心房调搏心脏负荷试验时是否随着心肌缺血的诱发而增大。方法: 分冠心病组和正常对照组,分别观察两组负荷试验前、负荷试验中最高心率时、负荷试验后即刻和2 min的QTd。结果: 冠心病组调搏最高心率时、调搏后即刻及2 min的QTd较调搏前显著增大(P<0.01),而对照组较调搏前无明显增大(P>0.05)。结论: 食管心房调搏心脏负荷试验中QTd增加可以作为诊断冠心病心肌缺血的有效指标。     

慢性阻塞性肺病极量运动后气体交换参数变化

目的：探讨慢性阻塞性肺病（ＣＯＰＤ）患者极量运动后气体交换参数的恢复及其受氨茶碱的影响。方法：２６例ＣＯＤＰ患者与２２名正常男性分别于静脉注射０．２５ｇ氨茶碱前后作极量运动试验。连续测量运动及其恢复期气体交换参数，并计算气体交换参数恢复半衰期和恢复程度。结果：极量运动后，ＣＯＰＤ患者气体交换参数恢复的半衰期较正常对照明显延长；在运动停止１０ｍｉｎ时，呼吸各参数恢复程度均在９５％以上，与正常人无明显