N末端脑钠肽对急性呼吸困难病因诊断的价值

目的探讨N-末端脑钠肽(Nt-ProBNP)在鉴别心源性和非心源性呼吸困难的临床价值,特别是鉴别舒张性心力衰竭(DHF)与慢性阻塞肺疾病(COPD)的价值。方法比较分析明确诊断的96例急性呼吸困难患者中心源性呼吸困难患者(56例)和非心源性呼吸困难患者(40例)的Nt-ProBNP水平,同时对25例DHF和28例COPD急性发作期的Nt-ProBNP、心脏彩超的左室射血分数(LVEF)、二尖瓣舒张早晚期流速峰值比(E/A)、E峰减速时间(DT),收缩期肺动脉压(SPAP)、肺功能(FEV1)进行分析比较。结果心源性呼吸困难患者Nt-ProBNP水平明显高于非心源性呼吸困难组[(4121.05±3326.24)pg/mlvs(729.16±524.06)pg/ml,P0.01];DHF患者Nt-ProBNP水平明显高于COPD亚组[(3853.97±2125.05)pg/mlvs(514.67±428)pg/ml,P0.01]。结论测Nt-ProBNP简便、快捷,可作为鉴别急性呼吸困难患者有临床价值的观察指标。特别对老年多发的、常见的、临床又难以判断的COPD与DHF的诊断有一定指导意义。     

高原地区慢性阻塞性肺疾病患者体重对呼吸困难的影响

目的探讨高原慢性阻塞性肺疾病(COPD)低体重(UW)和正常体重(NW)患者肺功能、呼吸肌力量和血气与呼吸困难的关系.方法对高原地区COPD缓解期体重指数(BMI)＜21kg/m2的36例和BMI在21～26kg/m2的32例两组患者测定一秒钟用力呼吸气容积(FEV1)占预计值百分比(FEV1%预计值)、FEV1/用力肺活量(FVC)比值(FEV1/FVC)、口腔最大吸气压(PImax)、最大呼气压(PEmax)、最大跨膈压(Pdimax)、呼吸肌力量指数(RMS)、动脉血氧分压(PaO2)和二氧化碳分压(PaCO2),并评估了呼吸困难等级.结果UW组平均BMI(17.8±1.2)kg/m2显著低于NW组(23.2±1.4)kg/m2,P＜0.01.UW组呼吸困难平均等级(3.9±0.9)显著高于NW组(2.9±0.7),P＜0.01.两组FEV1%预计值、FEV1/FVC差异无显著性(P＞0.05).UW组PaO2(53.7±6.2)mmHg显著低于、PaCO2(37.5±3.6)mmHg显著高于NW组[分别为(57.2±6.5)mmHg、(35.2±3.4)mmHg],P均＜0.05.UW组PImax(48.2±14.4)cmH2O、PEmax(62.7±16.2)cmH2O、Pdimax(54.3±15.6)cmH2O和RMS(55.5±15.1)cmH2O较NW组显著降低[分别为(61.7±15.9)cmH2O、(72.4±18.5)cmH2O、(66.9±17.2)cmH2O、(67.1±16.5)cmH2O](P＜0.01或P＜0.05).呼吸困难等级与PImax、PEmax、Pdimax、RMS、FEV1%预计值、FEV1/FVC呈显著负相关(P均＜0.01).结论高原地区COPD低体重患者呼吸困难较正常体重患者严重,其原因与营养不良所致的呼吸肌力量降低有重要关系.     

Clinical significance of bendopnea in heart failure—Systematic review and meta-analysis

BackgroundBendopnea is a symptom mediated by increased ventricular filling pressure during bending forward. Presence of bendopnea in patients can be easily evaluated without additional maneuver in several countries whose norms, habits, culture, and occupation relates to a higher frequency of bending forward. This information may prove valuable in routine clinical practice. We aimed to analyze the latest evidence on bendopnea in order to further define the clinical significance of this symptom.MethodsWe performed a comprehensive search on bendopnea in heart failure from inception up until January 2019 through PubMed, EuropePMC, EBSCOhost, Cochrane Central Database, and ClinicalTrials.gov.ResultsThere were 283 patients (31.76%) who have bendopnea, and a total of 891 patients from six studies were included. Bendopnea was associated with the presence of dyspnea [odds ratio (OR) 69.70 (17.35–280.07); <0.001], orthopnea [OR 3.02 (2.02–4.52); <0.001], paroxysmal nocturnal dyspnea [OR 2.76 (1.76–4.32); <0.001], and abdominal fullness [OR 7.50 (4.15–13.58); <0.001]. Association with elevated jugular venous pressure was shown in two studies. New York Heart Association (NYHA) functional class IV was more prevalent in patients with bendopnea [OR 7.58 (4.35–13.22); <0.001]. Bendopnea was also associated with increased mortality [OR 2.21 (1.34–3.66); 0.002].ConclusionBendopnea is associated with the presence of several signs and symptoms. This study also showed that bendopnea is one of the signs and symptoms of advanced heart failure associated with increased mortality. However, owing to the limited number of studies, further investigation is needed before drawing a definite conclusion.     

Predictors of Respiratory Decline Following Stereotactic Ablative Radiotherapy to Multiple Lung Tumors

IntroductionStereotactic ablative radiotherapy (SABR) is highly effective at controlling early stage primary lung cancer and lung metastases. Although previous studies have suggested that treating multiple lung tumors with SABR is safe, post-treatment changes in respiratory function have not been analyzed in detail.Patients and MethodsWe retrospectively identified patients with 2 or more primary lung cancers or lung metastases treated with SABR and analyzed clinical outcomes and predictors of toxicity. We defined a composite respiratory decline endpoint to include increased oxygen requirement, increased dyspnea scale, or death from respiratory failure not owing to disease progression.ResultsA total of 86 patients treated with SABR to 203 lung tumors were analyzed. A total of 21.8% and 41.8% of patients developed composite respiratory decline at 2 and 4 years, respectively. When accounting for intrathoracic disease progression, 12.7% of patients developed composite respiratory decline at 2 years. Of the patients, 7.9% experienced grade 2 or greater radiation pneumonitis. No patient- or treatment-related factor predicted development of respiratory decline. The median overall survival was 46.9 months, and the median progression-free survival was 14.8 months. The cumulative incidence of local failure was 9.7% at 2 years.ConclusionAlthough our results confirm that SABR is an effective treatment modality for patients with multiple lung tumors, we observed a high rate of respiratory decline after treatment, which may be owing to a combination of treatment and disease effects. Future studies may help to determine ways to avoid pulmonary toxicity from SABR.     

Diastolic function is associated with quality of life and exercise capacity in stable heart failure patients with reduced ejection fraction

Exercise capacity and quality of life (QOL) are important outcome predictors in patients with systolic heart failure (HF), independent of left ventricular (LV) ejection fraction (LVEF). LV diastolic function has been shown to be a better predictor of aerobic exercise capacity in patients with systolic dysfunction and a New York Heart Association (NYHA) classification ≥II. We hypothesized that the currently used index of diastolic function E/e'' is associated with exercise capacity and QOL, even in optimally treated HF patients with reduced LVEF. This prospective study included 44 consecutive patients aged 55±11 years (27 men and 17 women), with LVEF<0.50 and NYHA functional class I-III, receiving optimal pharmacological treatment and in a stable clinical condition, as shown by the absence of dyspnea exacerbation for at least 3 months. All patients had conventional transthoracic echocardiography and answered the Minnesota Living with HF Questionnaire, followed by the 6-min walk test (6MWT). In a multivariable model with 6MWT as the dependent variable, age and E/e'' explained 27% of the walked distance in 6MWT (P=0.002; multivariate regression analysis). No association was found between walk distance and LVEF or mitral annulus systolic velocity. Only normalized left atrium volume, a sensitive index of diastolic function, was associated with decreased QOL. Despite the small number of patients included, this study offers evidence that diastolic function is associated with physical capacity and QOL and should be considered along with ejection fraction in patients with compensated systolic HF.     

Effects of Home‐based Training at Dyspnea Threshold in Children Surgically Repaired for Congenital Heart Disease

The present investigation was aimed at assessing the effect of home‐based training on cardiorespiratory responses in children surgically corrected for congenital heart impairment using dyspnea threshold (DT) as training intensity. A group of 23 children aged 15 ± 1.4 years who had undergone surgical correction for congenital heart disease (CHD group) and 12 healthy children used as a control group performed an exercise protocol during which aerobic capacity, ventilatory threshold (VT), and DT were assessed. Afterwards, the CHD group was divided into two subgroups: trained and untrained subjects. Training sessions over a period of 2 months were performed at an intensity corresponding to DT by the CHD trained group. Dyspnea was scored according to a visual analog scale during the warm up, at each exercise stage, and during the recovery period. DT was located on the oxygen uptake/dyspnea curve when a sudden increase in the dyspnea score occured, while VT was defined according to the methodology previously employed by Beaver and colleagues. The results showed that children who had undergone surgery for CHD had reduced aerobic capacity. No significant difference was observed between VT and DT in children corrected for CHD. These two thresholds were highly related. Home‐based training at DT did not strongly improve aerobic capacity nor did it influence the relationship between VT and DT. Further studies should be conducted to confirm these preliminary findings, particularly when aerobic capacity is improved by training.     

Dysfonction microcirulatoire coronaire et 2D strain à la dobutamine chez un patient dyspnéique

Microcirculatory dysfunction despite the absence of angiographically obvious significant coronary artery disease may potentially generate symptomatic myocardial ischemia; comprehensive assessment both noninvasive and invasive could prove to be of critical interest. We report the case of a 54-year old patient referred for an exertion dyspnea that proved to be caused by both micro and microvascular dysfunction. We present key elements for diagnosis, functional evaluation and management and demonstrate the potential role of speckle tracking imaging in that setting.