BACKGROUND & AIMS: :Myocardial substrate metabolism provides the energy needed for cardiac contraction and relaxation. The normal adult heart uses predominantly fatty acids (FAs) as its primary fuel source. However, the heart can switch and use glucose (and to a lesser extent, ketones, lactate, as well as endogenous triglycerides and glycogen), depending on the metabolic milieu and superimposed conditions. FAs are not a wholly better fuel than glucose, but they do provide more energy per mole than glucose. Conversely, glucose is the more oxygen-efficient fuel. Studies in animal models of heart failure (HF) fairly consistently demonstrate a shift away from myocardial fatty acid metabolism and toward glucose metabolism. Studies in humans are less consistent. Some show the same metabolic switch away from FA metabolism but not all. This may be due to differences in the etiology of HF, sex-related differences, or other mitigating factors. For example, obesity, insulin resistance, and diabetes are all related to an increased risk of HF and may complicate or contribute to its development. However, these conditions are associated with increased FA metabolism. This review will discuss aspects of human heart metabolism in systolic dysfunction as measured by the noninvasive, quantitative method-positron emission tomography. Continued research in this area is vital if we are to ameliorate HF by manipulating heart metabolism with the aim of increasing energy production and/or efficiency.

背景与目标： : 心肌底物代谢提供心脏收缩和舒张所需的能量。正常的成人心脏主要使用脂肪酸 (FAs) 作为其主要燃料来源。然而，心脏可以切换和使用葡萄糖 (在较小程度上，酮，乳酸，以及内源性甘油三酯和糖原)，这取决于代谢环境和叠加条件。FAs并不是比葡萄糖更好的燃料，但它们确实比葡萄糖每摩尔提供更多的能量。相反，葡萄糖是氧气效率更高的燃料。对心力衰竭 (HF) 动物模型的研究相当一致地表明，从心肌脂肪酸代谢转向葡萄糖代谢。对人类的研究不太一致。有些人显示出与FA代谢相同的代谢开关，但并非全部。这可能是由于HF的病因差异，性别相关差异或其他缓解因素所致。例如，肥胖，胰岛素抵抗和糖尿病都与HF风险增加有关，并可能使其复杂化或促进其发展。然而，这些情况与FA代谢增加有关。这篇综述将讨论通过无创，定量方法-正电子发射断层扫描测量的收缩功能障碍中人体心脏代谢的各个方面。如果我们要通过控制心脏代谢以增加能量产生和/或效率来改善HF，那么在该领域的持续研究至关重要。

BACKGROUND & AIMS: :Pressure-volume analysis has provided critical insight into ventricular mechanics, and it has elucidated the underlying mechanisms of heart failure (HF). Renewed interest in ventriculovascular coupling, the interaction of the left ventricle and the arterial system, has developed from recent investigations focusing on the importance of heart rate control in systolic HF, blood pressure lability in the elderly, and acute pulmonary edema in patients with HF and a normal ejection fraction. These data suggest that abnormal ventriculovascular coupling may be an additional pathophysiologic mechanism underlying the development of HF with a normal ejection fraction and may provide a target for novel therapies.

背景与目标： : 压力-容积分析为心室力学提供了重要的见解，并阐明了心力衰竭 (HF) 的潜在机制。最近的研究对心室血管耦合，左心室与动脉系统的相互作用产生了新的兴趣，这些研究的重点是心率控制在收缩期HF中的重要性，老年人的血压不平和急性肺水肿。HF和正常的射血分数。这些数据表明，异常的心室血管耦合可能是射血分数正常的HF发展的另一种病理生理机制，并可能为新型疗法提供靶标。

BACKGROUND & AIMS: :The purpose of the present trial was to evaluate safety, tolerability, and effect on systolic blood pressure (SBP) of SER100 in a small group of patients with isolated systolic hypertension (ISH) in treatment with at least 1 antihypertensive drug. Eligible patients were randomized to either SER100 (10 mg) or placebo in a crossover design, and 2 doses were given subcutaneously (SC), 8 hours apart, on 2 consecutive days. On all treatment days patients were monitored with an ambulatory blood pressure measurement device for 12 daytime hours. Seventeen patients completed treatment. There were no serious or severe adverse events. Relative to placebo SER100 induced an average reduction of SBP during the 2 treatment days of 7.0 mm Hg (P = 0.0032), whereas the average reduction of diastolic blood pressure (DBP) over the same period was 3.8 mm Hg (P = 0.0011). For patients with ISH, this short-term cross-over study of SC SER100 demonstrated an acceptable safety profile and consistent, significant lowering of SBP and DBP. As initial clinical proof of concept for a new class of drugs, a nociceptin agonist peptide, the results were encouraging and warrant further research.

背景与目标： : 本试验的目的是评估一小群接受至少1种降压药治疗的单纯收缩期高血压 (ISH) 患者中SER100的安全性，耐受性和对收缩压 (SBP) 的影响。符合条件的患者在交叉设计中随机分配至SER100 (10 mg) 或安慰剂，并在连续2天的时间间隔8小时皮下注射2剂 (SC)。在所有治疗日中，使用动态血压测量设备对患者进行了12个白天的监测。17名患者完成了治疗。没有严重或严重的不良事件。相对于安慰剂SER100，在2个治疗日期间SBP平均降低7.0毫米Hg (P = 0.0032)，而同期舒张压 (DBP) 的平均降低为3.8毫米Hg (P = 0.0011)。对于ISH患者，SC SER100的这项短期交叉研究显示出可接受的安全性以及SBP和DBP的持续显着降低。作为一类新型药物 (伤害肽激动剂肽) 的初步临床概念证明，结果令人鼓舞，值得进一步研究。

BACKGROUND & AIMS: :Acute respiratory failure is followed by decreased left ventricular performance probably due to the right ventricle dilatation induced by pulmonary hypertension and intraventricular septal shift to the left. An anacrotic notch on the upstroke slope of the carotid curve was detected in 22 of 36 hemodynamic studies with simultaneous ECG, PCG and external pulse carotid curve recording in 7 burned patients with acute respiratory failure. Comparing the values (x +/- SEM) obtained in group with notch and in group without notch, PAPs, PAPm, PVRI were higher (56 +/- 2.30 mmHg; 32 +/- 0.99 mm Hg; 543 +/- 56.8 dyn x s/cm5/m2 versus 32 +/- 1.08 mm Hg; 20 +/- 0.9 mm Hg; 173 +/- 14.7 dyn x s/cm5/m2) and CI and LVSWI were lower (2.6 +/- 0.17 l/min/m2; 25.8 +/- 2.41 g x m/m2; versus 3.8 +/- 0.26 l/min/m2; 38.3 +/- 2.82 g x m/m2) in group with notch. As it is shown by 11 paired measurements where the notch disappeared immediately after starting vasodilator therapy PAPs, PAPm, PVRI decreased (from 54 +/- 3.1, 35 +/- 0.8 mm Hg, 498 +/- 64.1 dyn x s/cm5/m2 to 35 +/- 0.8, 21 +/- 1.1 mmHg, 189 +/- 18.4 dyn x s/cm5/m2 respectively) and heart performance improved. Since the left ventricle contractility (characterized by EF, PCWP, ICT) was normal in both groups, our findings suggest that critically high PAPs values (over 40 mmHg) cause a septal bulging at the beginning of the systole which in turn narrows the left ventricle outflow tract. Regarding to the clinical importance of the deteriorated biventricular function at the critically high PAPs evidenced by notch phenomenon on carotid curve but measurable only by indwelling pulmonary arterial catheterization always being a source of infection, the noninvasive parameters as independent variables were entered into canonical discriminant analysis. The ratio of the correctly classified cases was 89%.

背景与目标： : 急性呼吸衰竭后，左心室性能下降，可能是由于肺动脉高压和室间隔向左移位引起的右心室扩张。在36项血流动力学研究中，有22项同时记录了7例急性呼吸衰竭烧伤患者的ECG，PCG和外脉冲颈动脉曲线，在颈动脉曲线的上冲程斜率上检测到一个明显缺口。比较notch组和无notch组的值 (x/- SEM)，PAPm，PVRI较高 (56/- 2.30 mmHg; 32/-0.99毫米Hg; 543 +/- 56.8 dyn x s/cm5/m2与32 +/-1.08毫米Hg; 20 +/-0.9毫米Hg; 173 +/- 14.7 dyn x s/cm5/m2) 和CI和LVSWI较低 (2.6 +/- 0.17 l/min/m2; 25.8/- 2.41g x m/m2; 与3.8/- 0.26 l/min/m2相比; 38.3/- 2.82g x m/m2)。如11对测量结果所示，在开始血管扩张治疗后，PAPs、PAPm、PVRI立即消失 (从54 +/- 3.1、35 +/-0.8毫米Hg、498 +/- 64.1 dyn x s/cm5/m2降至35 +/- 0.8，分别为21/- 1.1 mmHg，189/- 18.4 dyn x s/cm5/m2) 和心脏性能得到改善。由于两组的左心室收缩力 (以EF，PCWP，ICT为特征) 均正常，因此我们的发现表明，极高的PAPs值 (超过40 mmHg) 会导致收缩期开始时间隔膨胀，从而使左心室变窄流出道。关于在颈动脉曲线上的notch现象证明但仅通过留置肺动脉导管才能测量的临界高PAPs上的双心室功能恶化的临床重要性始终是一个传染源，将非侵入性参数作为独立变量输入到典型判别分析中。正确分类的病例比例为89%。

BACKGROUND & AIMS: :Astaxanthin has strong antioxidant properties. We conducted a prospective pilot study on heart failure (HF) patients with left ventricular (LV) systolic dysfunction to investigate improvements in cardiac function and exercise tolerance in relation to suppression of oxidative stress by 3-month astaxanthin supplementation. Oxidative stress markers-serum Diacron reactive oxygen metabolite (dROM), biological antioxidant potential (BAP), and urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) concentrations, LV ejection fraction (LVEF), and 6-min walk distance (6MWD) were assessed before and after 3-month astaxanthin supplementation. Finally, the data of 16 HF patients were analyzed. Following 3-month astaxanthin supplementation, dROM level decreased from 385.6 ± 82.6 U.CARR to 346.5 ± 56.9 U.CARR (p = 0.041) despite no changes in BAP and urinary 8-OHdG levels. LVEF increased from 34.1 ± 8.6% to 38.0 ± 10.0% (p = 0.031) and 6MWD increased from 393.4 ± 95.9 m to 432.8 ± 93.3 m (p = 0.023). Significant relationships were observed between percent changes in dROM level and those in LVEF. In this study, following 3-month astaxanthin supplementation, suppressed oxidative stress and improved cardiac contractility and exercise tolerance were observed in HF patients with LV systolic dysfunction. Correlation between suppression of oxidative stress and improvement of cardiac contractility suggests that suppression of oxidative stress by astaxanthin supplementation had therapeutic potential to improve cardiac functioning.

背景与目标： : 虾青素具有很强的抗氧化性能。我们对患有左心室 (LV) 收缩功能障碍的心力衰竭 (HF) 患者进行了一项前瞻性初步研究，以研究与补充3个月虾青素抑制氧化应激有关的心功能和运动耐力的改善。氧化应激标志物-血清Diacron活性氧代谢物 (dROM)，生物抗氧化潜能 (BAP) 和尿中8-羟基-2 '-脱氧鸟苷 (8-OHdG) 浓度，左室射血分数 (LVEF) 和6分钟步行距离 (6MWD) 在补充虾青素3个月之前和之后进行评估。最后，对16例心衰患者的资料进行分析。补充虾青素3个月后，尽管BAP和尿8-OHdG水平没有变化，但dROM水平从385.6 ± 82.6 U.CARR降至346.5 ± 56.9 U.CARR (p = 0.041)。LVEF从34.1 ± 8.6% 增加到38.0 ± 10.0% (p = 0.031)，6MWD从393.4 ± 95.9 m增加到432.8 ± 93.3 m (p = 0.023)。观察到dROM水平的百分比变化与LVEF的百分比变化之间存在显着关系。在这项研究中，在LV收缩功能障碍的HF患者中，在补充虾青素3个月后，观察到氧化应激受到抑制，心脏收缩力和运动耐力得到改善。抑制氧化应激与改善心脏收缩力之间的相关性表明，补充虾青素抑制氧化应激具有改善心脏功能的治疗潜力。

BACKGROUND & AIMS: This study evaluates long-term ( > 10 years since surgery) right ventricular (RV) systolic function in patients who had previously undergone intraatrial baffle surgery for transposition of the great arteries. Studies suggest these patients are clinically stable and lead satisfactory lifestyles, but long-term ventricular performance is not known. Radionuclide angiocardiography was used to estimate RV ejection fraction in 58 patients a mean of 14 years after the Mustard operation. Repeat studies were performed in 32 patients. The absolute RV ejection fraction of 0.53 +/- 0.10 in our patients did not differ from normal values. Nine patients had a value < 0.42, placing them > 2 SDs below normal. Repeat RV ejection fraction decreased from 0.54 +/- 0.11 to 0.51 +/- 0.11 (p < 0.1) in 32 patients, and > 0.10 in 6. Thus, RV ejection fraction was abnormal in 9 of 58 patients (16%) evaluated > 10 years after a Mustard operation. Repeat studies demonstrate worsening in at least 6 of 32 patients (19%). These postoperative Mustard patients require continued evaluation, even in the absence of overt symptomatology.

背景与目标： 这项研究评估了先前接受过大动脉转位的房内挡板手术的患者的长期 (自手术以来> 10年) 右心室 (RV) 收缩功能。研究表明，这些患者临床稳定，生活方式令人满意，但长期心室性能尚不清楚。放射性核素心血管造影用于估计芥末手术后平均14年的58例患者的RV射血分数。对32例患者进行了重复研究。在我们的患者中，0.53 +/- 0.10的RV绝对射血分数与正常值没有差异。9名患者的值 <0.42，使他们> 2 SDs低于正常。32例患者的RV射血分数从0.54 +/- 0.11降至0.51 +/- 0.11 (p <0.1)，6例患者> 0.10。因此，在芥末手术后10年以上评估的58名患者 (16% 名) 中有9名RV射血分数异常。重复研究表明32例患者中至少有6例 (19% 例) 恶化。即使没有明显的症状，这些术后芥末患者也需要继续评估。

BACKGROUND & AIMS: OBJECTIVE:The objective of this study is to determine the reference ranges for filling time (FT) and systolic-to-diastolic time index (SDI) of the left ventricle (LV) by using spectral Doppler, and FT' and SDI' of the LV, right ventricle, and interventricular septum (IVS) by using tissue Doppler of the fetal heart. STUDY DESIGN:This prospective and cross-sectional study included 360 low-risk singleton pregnancies between 20 and 36 + 6 weeks of gestation. The SDI/SDI' is the sum of the ejection time, isovolumic contraction time, and isovolumic relaxation time (IRT) divided by the FT. We measured FT/FT' from the beginning of the opening click of the E wave of the mitral valve to the closing click of the A wave of the mitral valve. We used regression analysis to obtain the best-fit model polynomial equation for the parameters. Additionally, we assessed intra- and inter-observer reproducibility by using concordance correlation coefficient (CCC). RESULTS:There was a weak correlation among FT LV (r = 0.31, p < 0.0001), SDI LV (r = -0.23, p < 0.0001), and gestational age (GA). Additionally, there was a very weak positive correlation among FT' RV (r = 0.09, p = 0.0001), FT' LV (r = 0.07, p < 0.0001), FT' IVS (r = 0,08, p < 0.0001), and GA. In contrast, there was a very weak negative correlation among SDI' LV (r=-0.09, p < 0.0001), SDI' IVS (r=-0.05, p < 0.0021), and GA. There was no significative correlation between SDI' RV (r=-0.06, p < 0.081) and GA. Poor/very poor intra- and inter-observer reliability was observed for all the parameters (CCC = 0.19-0.79), whereas moderate intra- and inter-observer agreement was observed for all parameters (CCC = 0.37-0.72). CONCLUSIONS:The reference ranges for FT and SDI were determined by using spectral and tissue Doppler of the fetal heart and showed a poor reproducibility.

背景与目标：

BACKGROUND & AIMS: Systolic time intervals were measured noninvasively in 12 healthy control subjects (hemoglobin 12 to 15 Gm. per cent) and 32 cases of chronic anemia without underlying cardiovascular disease. It was found that in mild anemia (hemoglobin above 7 Gm. per cent), where cardiac output is known to be normal, the systolic time intervals were also normal. In severe anemia (hemoglobin below 7 Gm. per cent), where cardiac output is known to be high, the systolic time intervals showed the pattern usually associated with high cardiac output, i.e., increased left ventricular ejection time (LVET) and decreased pre-ejection period (PEP) and PEP/LVET ratio, only when congestive failure was absent. In severe anemia with congestive failure, the LVET was decreased, and PEP and PEP/LVET ratio were increased--the pattern associated with impaired myocardial performance, even though cardiac output is known to be high in such cases also.

背景与目标： 在12名健康对照受试者 (血红蛋白12至15 Gm。%) 和32例无潜在心血管疾病的慢性贫血患者中，无创测量了收缩时间间隔。发现在轻度贫血 (血红蛋白高于7 Gm。%) 中，已知心输出量正常，收缩时间间隔也正常。在严重贫血 (血红蛋白低于7 Gm。%) 中，已知心输出量很高，收缩期时间间隔显示出通常与高心输出量相关的模式，即，仅当没有充血性心力衰竭时，左心室射血时间 (LVET) 增加，射血前期 (PEP) 和PEP/LVET比率降低。在患有充血性衰竭的严重贫血中，LVET降低，PEP和PEP/LVET比率增加-这种模式与心肌功能受损有关，即使在这种情况下心输出量也很高。

BACKGROUND & AIMS: BACKGROUND:severity assessment in community-acquired pneumonia (CAP) is important as it is associated with significant mortality. In this study, we compared a previously suggested severity assessment rule for CAP- SOAR (systolic blood pressure, oxygenation, age and respiratory rate)- against the CURB-65 criteria. METHODS:we conducted a prospective study in three hospitals in Norfolk and Suffolk, UK. Consecutive patients with CAP were scored for severity with CURB-65 (n = 190), and SOAR (when there was sufficient information, n = 112). Mortality data was collected at 6 weeks. RESULTS:there were 100 males (53%). The age range was 18-101 years (mean 72 years, median 76 years). Sixty-five (34%) had severe pneumonia by CURB-65, and 56 patients out of 112 (50%) had severe pneumonia by SOAR. Patients with severe CAP were significantly more likely to be older, female, and to have higher urea levels and a lower PaO(2):FiO(2) ratio on admission. There were a total of 54 deaths during follow-up (33 of these in the SOAR-categorised group). There were 32 deaths (50%) in the severe and 22 deaths (18%) in the non-severe groups by CURB-65. There were 23 deaths (70%) in the severe and 22 deaths (30%) in the non-severe groups by SOAR. For CURB-65, sensitivity, specificity, positive and negative predictive values were 60.6, 72.2, 47.6 and 81.4%. For SOAR, the respective values were 69.7%, 58.2, 41.1 and 82.1%. CONCLUSION:SOAR had demonstrably better sensitivity, but lower specificity compared with CURB-65 in this patient cohort. SOAR might be more suitable for assessing disease severity as an alternative or adjunct to CURB-65, particularly in the elderly.

背景与目标：

BACKGROUND & AIMS: BACKGROUND:In patients with chronic heart failure, physical evaluation and clinical judgment may be inadequate for prognostic stratification. HYPOTHESIS:Information obtained with simple bedside tests would be helpful in patient management. METHODS:We report on 142 outpatients with systolic heart failure seen at our heart failure unit from 2007 to 2010 (ages 69.4 ± 8.9 years; ejection fraction [EF] 30.6 ± 6.1%; 43% with implanted defibrillators and/or resynchronization devices). At their first visit, we assessed levels of brain natriuretic peptide (BNP) (pg/mL), evaluated transthoracic conductance (TFC) (1/kΩ) by transthoracic bioimpedance, and performed echocardiography. RESULTS:Four-year mortality was 21.2%. At multivariate analysis, surviving and deceased subjects did not differ regarding New York Heart Association, age, gender, heart failure etiology, or EF at index visit. Patients who died had higher BNP and TFC (BNP = 884 ± 119 pg/mL vs 334 ± 110 pg/mL; TFC = 50 ± 8/kΩ vs 37 ± 7/kΩ, both P < 0.001]. Patients with BNP < 450 pg/mL and TFC < 40/kΩ had a 2.1% 4-year mortality, compared to 46.5% mortality of patients having BNP ≥ 450 pg/mL and TFC ≥ 40/kΩ. BNP ≥ 450 pg/mL and TFC ≥ 40/kΩ showed high sensitivity (91%) and specificity (88%)in identifying patients who died at follow-up. CONCLUSIONS:The combined use of BNP and impedance cardiography during the first assessment of a patient in a heart failure unit identified those carrying a worse medium-term prognosis. This approach could help the subsequent management of patients, allowing better clinical and therapeutic strategies.

背景与目标：

BACKGROUND & AIMS: Previous studies have suggested a potential association of elevated blood pressure (BP) and the development of diabetic neuropathy for individuals with insulin-dependent diabetes mellitus. In this study, we examined an association between BP and vibratory thresholds (assessment modality of large sensory nerve fiber function) for 33 participants with non-insulin-dependent diabetes mellitus. There were 19 women and 14 men aged 58 +/- 7 (mean +/- SD) years, with diabetes duration of 7 +/- 6 years and a body mass index of 29 +/- 5 kg/m2. None of the individuals were taking any medications that lower BP and all were negative for the presence of microalbuminuria. Vibratory thresholds were determined at three visits using a two-alternative, forced-choice procedure. BP was assessed by 24-h ambulatory BP monitoring. As expected, vibratory thresholds were higher for men than for women (6.3 +/- 4 v 4.2 +/- 3 vibration units) but there was no statistical difference after controlling for height. In multivariate analyses with vibratory thresholds as the dependent variable, duration of diabetes (P < 0.01), age (P < .01) and systolic BP (SBP) (P < .01) explained approximately 70% of the overall variability of the gender-specific (ie, female) model. The variability was similar (ie, 70% to 73%) no matter which SBP measure was available for modeling. In terms of diastolic blood pressure (DBP) measures, only the percentage of abnormal readings (ie, > 90 mm Hg) for day DBP was found to be independently associated with vibratory thresholds for women. The association of BP and large sensory nerve fiber dysfunction for nonnephropathic diabetic women found in this cross-sectional study warrants further investigation.

背景与目标： 先前的研究表明，对于胰岛素依赖型糖尿病患者，血压升高 (BP) 与糖尿病神经病变的发展可能相关。在这项研究中，我们检查了33名非胰岛素依赖型糖尿病参与者的BP与振动阈值 (大感觉神经纤维功能的评估方式) 之间的关联。有19名女性和14名男性，年龄58/- 7 (平均/- SD) 岁，糖尿病持续时间为7/- 6年，体重指数为29/-5千克/m2。没有人服用任何降低血压的药物，并且所有药物均对微量白蛋白尿的存在呈阴性。使用两种选择的强制选择程序在三次访问时确定振动阈值。通过24小时动态血压监测评估血压。如预期的那样，男性的振动阈值高于女性 (6.3/- 4 v 4.2/- 3振动单位)，但在控制身高后没有统计学差异。在以振动阈值为因变量的多变量分析中，糖尿病持续时间 (P <0.01)，年龄 (P < .01) 和收缩压 (SBP) (P < .01) 解释了性别特异性 (即女性) 模型总体变异性的大约70%。无论哪种SBP测量可用于建模，变异性都是相似的 (即，70% 73%)。就舒张压 (DBP) 测量而言，仅发现日间DBP的异常读数 (即> 90毫米Hg) 的百分比与女性的振动阈值独立相关。在这项横断面研究中发现的非肾病性糖尿病妇女的BP与大感觉神经纤维功能障碍的关系值得进一步研究。

BACKGROUND & AIMS: :In adults with congenital heart disease and a systemic right ventricle, subaortic ventricular systolic dysfunction is common. Echocardiographic assessment of systolic right ventricular (RV) function in these patients is important but challenging. The aim of the present study was to assess the reliability of conventional echocardiographic RV functional parameters to quantify the systolic performance of a subaortic right ventricle. We compared 56 contemporary echocardiograms and cardiac magnetic resonance studies in 37 adults, aged 26.9 ± 7.4 years, with complete transposition and a subaortic right ventricle. The fractional area change (FAC), lateral tricuspid annular plane systolic excursion, lateral RV systolic motion velocities by tissue Doppler, RV myocardial performance index, and the rate of systolic RV pressure increase (dp/dt) measured across the tricuspid regurgitant jet were assessed by echocardiography and correlated with the cardiac magnetic resonance-derived RV ejection fraction (EF). The mean RVEF was 48.0 ± 7.8%. FAC (r(2) = 0.206, p = 0.001) and dp/dt (r(2) = 0.173, p = 0.009) significantly correlated with RVEF, and the other nongeometric echocardiographic parameters failed to show a significant correlation with RVEF by linear regression analysis. FAC <33% and dp/dt <1,000 mm Hg/s identified a RVEF of <50% with a sensitivity of 77% and 69% and a specificity of 58% and 87%, respectively. In conclusion, in patients with a systemic right ventricle, routine nongeometric echocardiographic parameters of RV function correlated weakly with cardiac magnetic resonance-derived EF. RV FAC and the measurement of the rate of systolic RV pressure increase (dp/dt) should be preferentially used to assess systemic systolic function in adult patients with a subaortic right ventricle.

背景与目标： : 在患有先天性心脏病和全身性右心室的成年人中，主动脉下心室收缩功能障碍很常见。超声心动图评估这些患者的收缩期右心室 (RV) 功能很重要，但具有挑战性。本研究的目的是评估常规超声心动图RV功能参数的可靠性，以量化主动脉下右心室的收缩性能。我们比较了37例年龄在26.9 ± 7.4岁，完全转位和主动脉下右心室的成年人的56例当代超声心动图和心脏磁共振研究。组织多普勒的分数面积变化 (FAC)，外侧三尖瓣环形平面收缩偏移，外侧RV收缩运动速度，RV心肌性能指数，并通过超声心动图评估三尖瓣反流射流测得的收缩期RV压力升高率 (dp/dt)，并与心脏磁共振衍生的RV射血分数 (EF) 相关。平均RVEF为48.0 ± 7.8%。FAC (r(2) = 0.206，p = 0.001) 和dp/dt (r(2) = 0.173，p = 0.009) 与RVEF显著相关，其他非几何超声心动图参数未能通过线性回归分析显示与RVEF显著相关。FAC <33% 和dp/dt <1,000毫米Hg/s确定了 <50% 的RVEF，分别具有77% 和69% 的敏感性以及58% 和87% 的特异性。总之，在全身性右心室患者中，常规的RV功能非几何超声心动图参数与心脏磁共振衍生的EF相关性较弱。RV FAC和收缩期RV压力升高率 (dp/dt) 的测量应优先用于评估成年主动脉下右心室患者的全身收缩功能。

BACKGROUND & AIMS: :Clinical trials have demonstrated improved outcomes with cardiac resynchronization therapy in patients with heart failure and electrical evidence of dyssynchrony. There has been intense effort at developing imaging markers of dyssynchrony with the aim of improved risk stratification. However, these efforts have not been fruitful to date. This article discusses mechanisms of cardiac dyssynchrony, reviews clinical data supporting resynchronization therapy, and addresses the lack of convincing evidence to support the use of noninvasive imaging measures of dyssynchrony in improving patient management.

背景与目标： : 临床试验表明，心脏再同步化治疗可改善心力衰竭和不同步电证据的患者的预后。为了改善风险分层，人们一直在努力开发不同步的成像标记物。然而，这些努力迄今没有取得成果。本文讨论了心脏不同步的机制，回顾了支持再同步化治疗的临床数据，并解决了缺乏令人信服的证据来支持使用不同步的非侵入性成像措施来改善患者管理的问题。

BACKGROUND & AIMS: BACKGROUND:Hypoxia affects myocardial oxygen supply resulting in subclinical cardiac dysfunction in obstructive sleep apnea (OSA) patients, with cardiovascular complications being associated with increased oxidative burst (OB). The aims of our study were to assess left ventricular (LV) dynamic myocardial deformation and diastolic reserve at rest and upon exercise, along with OB determination in this patients subset. METHODS:Conventional echocardiography, Doppler myocardial imaging and LV 2D speckle tracking echocardiography were performed in 55 OSA patients with preserved LV ejection fraction (EF) and 35 age and sex-comparable healthy controls. Peripheral OB levels were evaluated by flow cytometry. RESULTS:Despite comparable LVEF, LV global longitudinal strain (GLS) was significantly reduced in OSA at rest (- 13.4 ± 3.8 vs - 18.4 ± 3.3 in controls, P <  0.001) and at peak exercise (- 15.8 ± 2.6 vs - 23.4 ± 4.3, P <  0.001). Systolic pulmonary artery pressure (sPAP) and E/E' ratios increase during effort were higher in OSA than in controls (ΔsPAP 44.3% ± 6.4 vs 32.3% ± 5.5, P <  0.0001, and ΔE/E' 87.5% ± 3.5 vs 25.4% ± 3.3, P <  0.0001, respectively). The best correlate of E/E' at peak stress was peak exertion capacity (r = - 0.50, P <  0.001). OB was also increased in OSA patients (P = 0.001) but, unlike OSA severity, was not associated with LV diastolic dysfunction. CONCLUSIONS:Evaluation of diastolic function and myocardial deformation during exercise is feasible through stress echocardiography. OSA patients with preserved LVEF show subclinical LV systolic dysfunction, impaired LV systolic and diastolic reserve, reduced exercise tolerance, and increased peripheral levels of OB. Therapy aimed at increasing LV diastolic function reserve might improve the quality of life and exercise tolerability in OSA patients.

背景与目标：

BACKGROUND & AIMS: :The effect of nose breathing on the systolic blood pressure was examined in ten healthy men. Nose breathing was increased above normal by exercise and tested by maximum bicycle ergometry. When the anterior part of the nose was dilated with Nozovent the nasal airflow increased by on average 29%. In this condition, all ten men could cycle at maximum load without mouth breathing and there was a significantly lower increase (13 mmHg) in the systolic blood pressure than when the nasal dilator was not used. The reason for this lower blood pressure increase is unknown. The hypothesis is put forward, however, that facilitated nose breathing decreases the respiratory work, which in turn lowers the systolic blood pressure during exercise.

背景与目标： : 在10名健康男性中检查了鼻子呼吸对收缩压的影响。通过运动和最大自行车测功测试，鼻子呼吸增加到正常以上。当鼻子的前部用Nozovent扩张时，鼻气流平均增加29%。在这种情况下，所有十名男性都可以在最大负荷下循环而无需张口呼吸，并且收缩压的升高幅度 (13 mmHg) 明显低于不使用鼻扩张器时。血压降低的原因尚不清楚。然而，提出了这样的假设，即促进鼻子呼吸会减少呼吸工作，进而降低运动期间的收缩压。