Calculation of the cardiothoracic ratio from portable anteroposterior chest radiography

Cardiothoracic ratio (CTR), the ratio of cardiac diameter (CD) to thoracic diameter (TD), is a useful screening method to detect cardiomegaly, but is reliable only on posteroanterior chest radiography (chest PA). We performed this cross-sectional 3-phase study to establish reliable CTR from anteroposterior chest radiography (chest AP). First, CD(Chest PA)/CD(Chest AP) ratios were determined at different radiation distances by manipulating chest computed tomography to simulate chest PA and AP. CD(Chest PA) was inferred from multiplying CD(Chest AP) by this ratio. Incorporating this CD and substituting the most recent TD(Chest PA), we calculated the 'corrected' CTR and compared it with the conventional one in patients who took both the chest radiographies. Finally, its validity was investigated among the critically ill patients who performed portable chest AP. CD(Chest PA)/CD(Chest AP) ratio was {0.00099 × (radiation distance [cm])} + 0.79 (n = 61, r = 1.00, P < 0.001). The corrected CTR was highly correlated with the conventional one (n = 34, difference: 0.00016 ± 0.029; r = 0.92, P < 0.001). It was higher in congestive than non-congestive patients (0.53 ± 0.085; n = 38 vs 0.49 ± 0.061; n = 46, P = 0.006). Its sensitivity and specificity was 61% and 54%. In summary, reliable CTR can be calculated from chest AP with an available previous chest PA. This might help physicians detect congestive cardiomegaly for patients undergoing portable chest AP.     

Ultrasound M-mode assessment of diaphragmatic kinetics by anterior transverse scanning in healthy subjects

The purpose of this study was to set an effective standardized method to assess diaphragmatic kinetics by ultrasound. Forty healthy volunteers were submitted to a B- and M-mode ultrasound study using a convex transducer positioned in the subcostal anterior area for transverse scanning. Ultrasound examination was completed in 38/40 cases (95%), spending on average <10 min for examination. The resting and forced diaphragmatic excursions were 18.4 ± 7.6 and 78.8 ± 13.3 mm, respectively, unrelated to demographic or anthropometric parameters: intraobserver variability on three successive measurements resulted in 6.0% and in 3.9%, respectively. An inexperienced sonographer completed the ultrasound examination in 37/40 cases, spending on average >15 min, with significant, although marginal, interobserver variability (31.9% and 14.7% for resting and forced diaphragmatic excursion, respectively). Bedside ultrasonography by an anterior subcostal transverse scanning on semi-recumbent patient proves to be a safe, feasible, reliable, fast, relatively easy and reproducible way to assess diaphragm movement. (E-mail: americotesta@gmail.com)     

Effects of inspiratory muscle training in patients with heart failure

Aim

To investigate the effects of inspiratory muscle training (IMT) on functional capacity and balance, respiratory and peripheral muscle strength, pulmonary function, dyspnea, fatigue, depression, and quality of life in heart failure patients.

Methods

A prospective, randomized controlled, double-blinded study. Thirty patients with heart failure (NYHA II-III, LVEF<40%) were included. Sixteen patients received IMT at 40% of maximal inspiratory pressure (MIP), and 14 patients received sham therapy (15% of MIP) for 6 weeks. Functional capacity and balance, respiratory muscle strength, quadriceps femoris muscle strength, pulmonary function, dyspnea, fatigue, quality of life, and depression were evaluated.

Results

Functional capacity and balance, respiratory and peripheral muscle strength, dyspnea, depression were significantly improved in the treatment group compared with controls; quality of life and fatigue were similarly improved within groups (p < 0.05). Functional capacity (418.59 ± 123.32 to 478.56 ± 131.58 m, p < 0.001), respiratory (MIP = 62.00 ± 33.57 to 97.13 ± 32.63 cmH₂O, p < 0.001) and quadriceps femoris muscle strength (240.91 ± 106.08 to 301.82 ± 111.86 N, p < 0.001), FEV₁%, FVC% and PEF%, functional balance (52.73 ± 3.15 to 54.25 ± 2.34, p < 0.001), functional dyspnea (2.27 ± 0.88 to 1.07 ± 0.79, p < 0.001), depression (11.47 ± 7.50 to 3.20 ± 4.09, p < 0.001), quality of life, fatigue (42.73 ± 11.75 to 29.07 ± 13.96, p < 0.001) were significantly improved in the treatment group. Respiratory muscle strength (MIP = 78.64 ± 35.95 to 90.86 ± 30.23 cmH₂O, p = 0.001), FVC%, depression (14.36 ± 9.04 to 9.50 ± 10.42, p = 0.011), quality of life and fatigue (42.86 ± 12.67 to 32.93 ± 15.87, p = 0.008) were significantly improved in the control group.

Conclusion

The IMT improves functional capacity and balance, respiratory and peripheral muscle strength; decreases depression and dyspnea perception in patients with heart failure. IMT should be included effectively in pulmonary rehabilitation programs.     

Effectiveness of chest radiography,lung ultrasound and thoracic computed tomography in the diagnosis of congestive heart failure

Hydrostatic pulmonary edema is as an abnormal increase in extravascular water secondary to elevated pressure in the pulmonary circulation, due to congestive heart failure or intravascular volume overload. Diagnosis of hydrostatic pulmonary edema is usually based on clinical signs associated to conventional radiography findings. Interpretation of radiologic signs of cardiogenic pulmonary edema are often questionable and subject. For a bedside prompt evaluation, lung ultrasound (LUS) may assess pulmonary congestion through the evaluation of vertical reverberation artifacts, known as B-lines. These artifacts are related to multiple minimal acoustic interfaces between small water-rich structures and alveolar air, as it happens in case of thickened interlobular septa due to increase of extravascular lung water. The number, diffusion and intensity of B lines correlates with both the radiologic and invasive estimate of extravascular lung water. The integration of conventional chest radiograph with LUS can be very helpful to obtain the correct diagnosis. Computed tomography (CT) is of limited use in the work up of cardiogenic pulmonary edema, due to its high cost, little use in the emergencies and radiation exposure. However, a deep knowledge of CT signs of pulmonary edema is crucial when other similar pulmonary conditions may occasionally be in the differential diagnosis.     

甲磺酸伊马替尼致间质性肺炎1例并文献复习

目的 提高对甲磺酸伊马替尼所致间质性肺炎的认识,做到早期诊断和治疗,改善患者预后.方法 对北京大学首钢医院呼吸内科诊治的1例甲磺酸伊马替尼致间质性肺炎患者的临床资料进行回顾性分析,并进行相关文献复习.结果 患者女性,小肠间质瘤术后服用甲磺酸伊马替尼3个半月后出现水肿、呼吸困难,入院后胸部CT提示双肺弥漫分布的斑片影,BALF显示细胞总数升高(0.54×109/L),其中淋巴细胞56％.除外感染、自身免疫性疾病和其他药物因素,诊断甲磺酸伊马替尼导致的间质性肺炎,停止服用伊马替尼3周后患者呼吸困难无改善,后加用糖皮质激素治疗,激素治疗约2周后患者呼吸困难明显减轻,胸部CT双肺斑片影较前部分吸收,激素治疗4个月后复查胸部CT病变较前明显吸收,但遗留肺间质纤维化改变,停用激素治疗.随访患者未再服用甲磺酸伊马替尼,2年及5年后胸部CT较前无明显变化,3年后患者因小肠间质瘤复发再次手术切除.结论 服用甲磺酸伊马替尼后出现呼吸困难症状应考虑间质性肺炎可能,早期诊断、停药和应用糖皮质激素治疗可获得显著效果,停药后应长期随访患者基础疾病及肺部情况.通过这此例报道并进行文献复习有助于提高对甲磺酸伊马替尼所致间质性肺炎的认识.     

义诊在轻中度呼吸困难管理中的应用探讨

目的 探讨呼吸疾病义诊形式在轻中度呼吸困难管理中的价值及相关资料分析.方法 借助“世界哮喘日”与“世界COPD日”集中宣教契机,组织呼吸疾病义诊,服务轻中度呼吸困难人群并收集近5年来参加义诊者556人次的临床资料,包括年龄、体质量指数(BMI)、吸烟指数、肺功能(FVC％ pred、FEV1％ pred)、血压、心率、血氧饱和度、心率血压乘积(rate-pressure product,RPP)等,应用SPSS软件进行统计分析.结果 肺通气功能不全比例69.78％,以混合性通气功能障碍表现为主,FEV1％ pred中重度减退者可达45.10％;除BMI和心率外,其他指标均呈现出性别差异,即女性组FEV1％ pred、FVC％ pred(t值分别为2.244、2.459,P值均＜0.05)及SPO2(Z=-3.665,P＜0.01)高于男性组,差异有统计学意义;男性组年龄、收缩压、舒张压、吸烟指数显著高于女性组(Z值分别为-3.903、-2.969、-2.742、-11.481,P值均＜0.01);女性组RPP与FEV1％ pred呈负相关(r=-0.134,P＜0.05),与FVC％ pred呈显著负相关(r=-0.168,P＜0.01);而男性组RPP与FVC％ pred、FEV1％ pred均无明显相关性(r值分别为-0.102、-0.066,P值均＞0.05).结论 在近阶段尚无就医计划的轻中度呼吸困难人群管理中要重视性别差异,采用呼吸疾病义诊形式进行健康宣教,可使相应群体获益.     

Noninfectious pneumonitis with the use of mTOR inhibitors in breast cancer

The mammalian target of rapamycin (mTOR) inhibitor class of drugs represents the newest addition to the armamentarium of therapies for hormonally driven breast cancer. It has recently been shown that the addition of mTOR inhibitor everolimus to aromatase inhibitors in hormone receptor–positive breast cancers improves progression-free survival. However, a clinically significant toxicity associated with this class of drugs is the development of noninfectious pneumonitis (NIP). Although generally mild and manageable, everolimus-induced NIP requires prompt diagnosis and management. This article will provide a brief overview of data relating to dysregulation of the phosphatidylinositol-3-kinase/protein kinase B/mTOR pathway in breast cancer; review the literature relating to the efficacy and safety of mTOR inhibitors in breast cancer; and evaluate the incidence, severity, and optimal management of mTOR inhibitor–related NIP in breast cancer.     

氨基末端B型尿钠肽前体对心源性与呼吸源性呼吸困难的鉴别诊断价值

目的：探讨氨基末端B型尿钠肽前体（NT-proBNP）在急性心源性及呼吸源性呼吸困难鉴别诊断中的价值。方法：2007年10月-2008年10月收治的急性呼吸困难患者,根据病史、体格检查、胸片、心电图等作出初步诊断,分为3组。组A：由心衰引起（心源性）;组B：呼吸道疾患引起（呼吸源性）;组C1无法确定原因（两种疾病同时存在）。通过检测NT—proBNP水平以了解其对呼吸困难病因诊断的临床意义。并由2住心血管专业副主任以上医师综合住院期间做的心超LVEF值、血气分析、胸部CT,肺功能等检查结果。对治疗方案的疗效而作出明确诊断。结果：172例患者中,初诊为组A：59例;组B：41例;组C：72例。最后确诊：属于心源性呼吸困难有84例,NT—proBNP的均值为2993±183pg·mL^-1;呼吸源性为88例,NT—proB—NP的均值为986±149Pg·mL^-1.年龄在65岁以上者中,心源性呼吸困难组,NT-proBNP的均值为3274±174Pg·mL^-1,而呼吸源性呼吸困难组为1003±157Pg·mL^-1;65岁以下者中,心源性呼吸困难组,NT—proBNP的均值为2742±142pg·mL^-1,呼吸源性呼吸困难组为827±159pg·ml,两组比较均存在显著性差异（P〈0．01）。当选用NT—proBNP的切点值为50Pg·mL^-1时,其敏感性高达100％,但特异性只有9．41％,阳性预测值（PPV）为52．73％,阴性预测值（NPV）则高达100％,准确性为55．23％。当选用切点值为450pg·mL^-1时,其敏感性仍可达93．10％,特异性上升到61．180A,PPV为71．05％,NPV为89．66％,准确性为77．33％。结论：NT-proBNP浓度越高,诊断心源性呼吸困难的价值越大。但相与诊断心源性呼吸困难相比,NT—proBNP对排除心源性呼吸困难更有价值。     

血清N末端B型钠尿肽原在不明原因呼吸困难病因分析中的临床意义

目的探讨血清N末端B型钠尿肽原(NT-proBNP)在不明原因呼吸困难病因分析的临床意义。方法针对急诊入院不明原因呼吸困难的患者,应用电化学发光法检测患者血清NT-proBNP的浓度;详细追问病史、体格检查,结合心电图、心脏彩超、胸片、肺功能测定等相关检查,进一步明确患者呼吸困难的原因。结果心源性呼吸困难患者血清NT-proBNP浓度在829.20~18700.50 pg/ml间,NT-proBNP呈偏态分布,中位数水平分别为4474.80 pg/ml,非心源性呼吸困难患者血清NT-proBNP浓度在10.20~389.50 pg/ml间,NT-pro BNP呈偏态分布,中位数水平分别为174.20 pg/ml,两组患者血清NT-proBNP浓度中位数比较差异有统计学意义(P值0.05)。结论血清NT-proBNP浓度在鉴别心源性或非心源性呼吸困难中有重要意义。