肺动脉高压合并阻塞性睡眠呼吸暂停患者的临床特点

目的:观察肺动脉高压合并阻塞性睡眠呼吸暂停(OSA)患者的临床特点。方法:对2016-04至2016-08期间,对我院肺血管病中心住院接受右心导管检查的65例肺动脉高压患者进行睡眠呼吸监测,记录患者的临床常规检查、睡眠呼吸监测和右心导管指标。根据呼吸暂停低通气指数(AHI)≥5诊断OSA,对比分析有无OSA患者的各项指标。结果:65例患者的平均年龄(41.98±15.26)岁,其中72.31%(47/65)的患者为女性。65例患者中有26例(40%)存在OSA,平均AHI为18.12±13.40。与无OSA患者比,有OSA患者年龄、男性患者比例、慢性血栓栓塞性肺动脉高压患者比例、肺部疾病或低氧性肺动脉高压患者比例、AHI、呼吸暂停指数(AI)、阻塞性呼吸暂停指数(o AI)、夜间低氧时间10%患者比例、动脉血氧饱和度(Sa O2)90%时间、体重指数(BMI)、纽约心脏协会(NYHA)心功能Ⅲ级患者比例、N末端B型利钠肽原(NT-pro BNP)水平均升高;平均血氧饱和度、最低血氧饱和度、动脉血氧分压(Pa O2)、6分钟步行试验距离(6MWD)、心指数(CI)均降低,差异均有统计学意义(P均0.05)。有无OSA患者的用药谱是相似的。结论:夜间低氧和OSA常见于肺动脉高压患者,高龄、高BMI和男性是肺动脉高压患者合并OSA的危险因素。合并OSA的肺动脉高压患者血氧分压尤其是夜间血氧分压更低,低氧时间更长且心功能损害较无OSA患者更严重。因此,对于肺动脉高压患者应进行睡眠呼吸监测,了解有无睡眠呼吸暂停以及低氧的存在。     

阻塞性睡眠呼吸暂停低通气综合征93例临床分析

目的通过检测阻塞性睡眠呼吸暂停低通气综合征(OSAHS)患者血清血管内皮生长因子(VEGF)质量浓度,探讨其与肺动脉高压的关系。方法选择2003-02~2004-09温州医学院附属第一医院收治的93例因打鼾就诊的患者,对18例单纯鼾症、39例轻中度及36例重度OSAHS患者于多导睡眠图(PSG)检测后次日晨7:00测定其血清VEGF质量浓度,并予超声心动图检测了其中31例OSAHS患者肺动脉压力。结果PSG检测结果显示与单纯鼾症组比,OSAHS组存在夜间低氧;且重度组比轻中度OSAHS组夜间低氧更严重(均有统计学意义)。与单纯鼾症组比较,VEGF质量浓度在重度OSAHS组中明显升高(P<0·05),并分别与衡量病情及夜间低氧情况指标呈正相关,与夜间最低经皮血氧饱和度(SpO2)呈负相关。结论中重度OSAHS患者存在夜间低氧饱和度,同时有VEGF增高。     

稳定期慢性阻塞性肺疾病患者夜间睡眠特点及长效抗胆碱能药物治疗的影响

目的:研究稳定期慢性阻塞性肺疾病(COPD)患者夜间睡眠的特点以及噻托溴铵粉吸入剂治疗对COPD患者肺功能及夜间睡眠的影响。方法:入选2010年9月至2011年8月18例中到重度肺功能受损的COPD患者,基线肺功能检查第1秒用力呼气容积(FEV1)在预计值参考范围的30%~80%,且支气管舒张实验阴性。其中男17例,女1例,年龄54~78(65.7±6.6)岁,平均体质量指数(BMI)为24.1±2.5(19.6~27.3)。入组后予以患者吸入皮质激素(ICS)单药洗脱2周后,予正规的ICS+长效抗胆碱支气管扩张剂(LAMA)治疗3个月。在基线期和3个月后分别进行肺功能及全夜多导睡眠图(PSG)检测。结果:稳定期无需氧疗的中重度肺功能损害COPD患者夜间低氧并不显著[呼吸紊乱指数(RDI)7.1±7.5,最低指脉搏氧饱和度(SpO2)83.9%±8.4%、SpO2低于90%的时间(7.4±12.2)min、平均SpO294.2%±2.4%],且与基础肺功能相关性不大,RDI主要仍与患者BMI相关(r=0.3,P=0.02),但睡眠期存在明显的微觉醒时间(平均微觉醒指数27.1±16.0)。经短期治疗前后肺功能[FEV1、用力肺活量(FVC)、残气量/肺总量比(RV/TLC)]及夜间睡眠低氧状况(夜间睡眠期RDI、最低SpO2、SpO2低于90%的时间、平均SpO2)变化不明显。但其中患者治疗后微觉醒指数明显下降(27.1±16.0比17.1±13.4,P=0.01)。结论:中重度肺功能损害的稳定期COPD患者夜间存在以微觉醒增多为特征的睡眠紊乱,LAMA治疗能提高COPD患者夜间睡眠质量;短期治疗对肺功能影响不大。     

阻塞性睡眠呼吸暂停影响右心心肺耦联系统的研究进展

阻塞性睡眠呼吸暂停(obstructive sleep apnea,OSA)是一种常见的睡眠呼吸紊乱性疾病,其特点是睡眠中上呼吸道塌陷从而出现反复的呼吸暂停或低通气。这种疾病伴随着夜间间歇性低氧、高碳酸血症、睡眠中断、打鼾和白天嗜睡等症状,其患病率在9%~38%之间,尤以中老年男性居多[1]。OSA通过促进交感神经系统激活、氧化应激、炎症反应、血管内皮功能受损等机制,导致动脉高压及心脏收缩和舒张功能障碍,增加了心血管疾病发生的风险[2]。由于夜间间断性低氧导致了OSA患者肺血管收缩和重构,肺动脉压力升高,右心室(right ventricular,RV)后负荷增加等一系列心肺耦联系统的损伤[3]。     

不同程度阻塞性睡眠呼吸暂停对非梗阻性肥厚型心肌病患者临床特征的影响

目的:研究阻塞性睡眠呼吸暂停(OSA)对非梗阻性肥厚型心肌病(HCM)患者临床特征的影响。方法:回顾性分析2010年2月至2018年12月间,我院诊断为非梗阻性HCM且行睡眠呼吸监测的患者共241例。记录患者的一般临床资料、超声心动图参数、睡眠呼吸监测参数等。根据呼吸暂停低通气指数(AHI)将患者分为无OSA组、轻度OSA组和中-重度OSA组,比较三组患者间的临床特点。结果:共有164例(68.0%)非梗阻性HCM患者合并OSA,中-重度OSA患者110例(45.6%)。三组患者年龄[(47.1±13.1)岁vs.(51.4±11.8)岁vs.(54.7±11.7)岁,P0.001]和体重指数[(24.5±3.3)kg/m~2 vs.(26.7±3.3)kg/m~2 vs.(27.7±4.1)kg/m~2,P0.001]均随着OSA严重程度增加而增加。与无OSA组和轻度OSA组患者相比,中-重度OSA组患者男性患者比例更高,合并高血压、高脂血症、吸烟史、冠心病和NYHA心功能分级Ⅱ～Ⅲ级的患者比例更高(P均0.05)。中-重度OSA组患者血清C反应蛋白水平高于无OSA组和轻度OSA组患者(P0.05)。三组患者左心室射血分数和左心室舒张末期内径差异均无统计学意义(P均0.05),但中-重度OSA组的左心房直径和升主动脉内径均显著大于无OSA组和轻度OSA组患者(P均0.05)。中-重度OSA组睡眠期间平均心率也显著高于无OSA组和轻度OSA组患者(P0.05)。Pearson相关分析显示,经过自然对数(ln)转换,ln(AHI+1)与左心房直径(r=0.176,P=0.006)和升主动脉内径(r=0.318,P=0.001)呈显著正相关。结论:OSA在非梗阻性HCM患者中非常常见,心血管代谢异常及心脏重构程度随OSA严重程度增加而增加,对该类患者应积极行睡眠呼吸监测筛查OSA。     

阻塞性睡眠呼吸暂停与冠心病的相关性及临床特点

目的了解国人阻塞性睡眠呼吸暂停(OSA)患者中冠心病(CAD)的发生率,并探讨两者之间关系和临床特点。方法对2009年01月-2010年6月以胸痛待查入住阜外医院心内科五区行冠状动脉造影(CAG)的患者,进行多导睡眠呼吸监测,收集其临床资料和常规生化指标。结果 257例患者入选,无OSA组、轻度OSA、中度OSA和重度OSA中,经CAG确诊CAD的患者分别为44.6%:60.0%:70.5%:72.1%(P0.01);Logistic回归分析,最低血氧饱和度与CAD的发生显著相关(P=0.024)。结论 CAD的发生率在OSA患者中明显增加,随着OSA的严重程度呈递增趋势;多元回归分析,OSA是冠心病的独立危险因素。     

阻塞性睡眠呼吸暂停患者体质量指数与夜间低氧血症的关系

目的 探讨阻塞性睡眠呼吸暂停(obstructive sleep apnea,OSA)患者体质量指数(BMI)与夜间低氧血症的关系.方法 回顾性分析1 899例经多导睡眠图(PSG)检查确诊为OSA患者(年龄为21～80岁),根据OSA患者BMI分正常体质量组(18.5 kg/m2≤BMI≤24 kg/m2)、超重组( 24 kg/m2＜BMI≤28 kg/m2)和肥胖组(BMI＞28 kg/m2),分析OSA患者的BMI、年龄与血氧饱和度＜90％时间占总睡眠时间百分比(TS90％)的相关性,比较不同体质量组OSA患者的TS90％差异.结果 OSA患者夜间TS90％与BMI呈正相关(r=0.421,P＜0.05),与年龄呈负相关(r=-0.087,P＜0.05).在年龄和AHI相似的情况下,其TS90％随着BMI的增加而加重,正常体质量组、超重组和肥胖组TS90％分别为(9.3±12.5)％、(10.0±10.0)％和(13.8±14.4)％,三组间差异有统计学意义(F =13,330,P=0.000).结论 伴有肥胖的OSA患者将加重夜间的低氧血症.     

阻塞性睡眠呼吸暂停患者呼吸事件相关觉醒与脉率升高的关系

目的探讨阻塞性睡眠呼吸暂停(OSA)患者呼吸事件相关觉醒与脉率升高的关系, 评估脉率升高能否作为觉醒的替代标志物。方法选取2021年1月至2022年8月就诊于天津医科大学总医院呼吸与危重症医学科睡眠中心进行多导睡眠监测(PSG)的80例患者[男性40例、女性40例、年龄18～63(37±13)岁]稳定的非快速眼动睡眠(NREM)的PSG记录, 比较每个呼吸事件相关觉醒开始前10 s的平均脉率、最低脉率和觉醒结束后10 s内的最高脉率, 同时分析觉醒指数与脉率升高指数(PRRI)以及ΔPR1(最高脉率-最低脉率)和ΔPR2(最高脉率-平均脉率)分别与呼吸事件持续时间、觉醒持续时间、脉搏血氧饱和度(SpO2)下降幅度和最低SpO2的相关性。对其中53例患者各选择NREM时10个不伴觉醒的事件和10个伴有觉醒的事件(按SpO2下降幅度进行匹配), 比较两组事件终止前后ΔPR。此外, 选取50例患者同步进行便携式睡眠监测(PM), 并分为非重度OSA组(n=22)和重度OSA组(n=28), 分别采用呼吸事件后ΔPR≥3、≥6、≥9、≥12次作为觉醒的替代标志物, 将ΔPR进行手动评分并整合到...     

高血压合并阻塞性睡眠呼吸暂停患者血清胱抑素C的危险因素

目的:探讨高血压合并阻塞性睡眠呼吸暂停(obstructive sleep apnea,OSA)患者血清胱抑素(CysC)的危险因素。方法:83例高血压患者行血生化和多导睡眠仪检测,根据多导睡眠仪的监测结果,符合OSA诊断的41例患者作为高血压合并OSA组,42例单纯高血压患者作为高血压组。结果:(1)高血压合并OSA组的体质量、体质量指数、颈围、腰围、腰臀比、收缩压、夜间缺氧事件总数、夜间缺氧事件总时间、睡眠呼吸暂停低通气指数(AHI)、空腹血糖、餐后2h血糖、CysC、总胆固醇、三酰甘油和低密度脂蛋白胆固醇均高于高血压组(P均0.05);(2)Pearson相关或Spearman相关分析显示,血清CysC与体质量、颈围、腰围、腰臀比、夜间缺氧事件总数、夜间缺氧事件总时间和AHI呈正相关(P均005);(3)多元线性逐步回归分析示仅夜间缺氧事件总数(β=0.484,P0.05)和AHI(β=0.481,P0.05)与血清CysC的相关性有统计学意义。结论:夜间缺氧事件总数和AHI是高血压合并OSA患者血清CysC的独立危险因素。     

恢复期新型冠状病毒肺炎患者合并阻塞性睡眠呼吸暂停的相关因素分析

目的探讨恢复期新型冠状病毒肺炎患者阻塞性睡眠呼吸暂停(OSA)的相关因素。方法本研究为病例对照研究。采用非随机抽样的方法纳入2020年3月12日至2020年4月23日因新型冠状病毒核酸长期阳性而连续转诊至武汉大学人民医院东院的107例患者为研究对象。根据是否合并OSA分为2组, 其中合并OSA组75例, 未合并OSA组32例, 收集所有患者的临床资料并进行睡眠监测, 应用SPSS 22.0统计软件比较2组临床资料的差异, 采用多因素logistic回归模型分析恢复期新型冠状病毒肺炎患者发生OSA的相关因素。结果纳入的107例患者呼吸暂停低通气指数为22.2(12.5, 31.0)次/h, 75例(70.1%)合并OSA。与未合并OSA组相比, 合并OSA组男性比例更高(2组男女比分别为43∶32比7∶25, χ²=11.32, P=0.001);合并OSA组高血压[45.3%(34/75)比18.8%(6/32)]、糖尿病[22.7%(17/75)比6.3%(2/32)]和冠状动脉粥样硬化性心脏病[13.3%(10/75)比0]的发病率均更高(χ²值分别为6.77、4.14、4.66, P值均<0.05);但2组的年龄比较差异无统计学意义[58.0(45.0, 67.0)岁比52.5(37.3, 60.8)岁, Z=1.73, P=0.084]。多因素logistic回归分析显示, 男性(RR=6.129, 95%CI:1.217~30.867, P=0.028)、STOP-Bang问卷(RR=28.569, 95%CI:3.633~224.681, P=0.001)、匹兹堡睡眠质量指数(RR=5.309, 95%CI:1.593~17.687, P=0.007)和高血压(RR=6.805, 95%CI:1.014~45.684, P=0.048)与恢复期新型冠状病毒肺炎患者合并OSA有关。结论 OSA是恢复期新型冠状病毒肺炎患者的常见合并症, 男性、STOP-Bang评分、匹兹堡睡眠质量指数以及高血压与恢复期新型冠状病毒肺炎患者合并OSA相关。     

阻塞性睡眠呼吸暂停与间质性肺疾病严重程度的临床分析

目的分析阻塞性睡眠呼吸暂停(OSA)合并间质性肺疾病(ILD)患者的临床资料,探讨OSA与ILD患者疾病严重程度的关系。 方法回顾性分析2010年2月至2019年12月于我院诊治的51例ILD合并OSA患者的临床资料,包括动脉血气分析、B型脑钠肽,以及睡眠呼吸监测、肺功能检查、心脏彩色多普勒超声检查等数据,采用Warrick评分方法评估ILD病变严重程度和范围。分析睡眠参数与ILD患者心肺功能、肺间质病变严重程度的关系,探索预测重度肺间质病变的相关指标。 结果ILD-OSA患者睡眠最低血氧饱和度与三尖瓣返流速率(TRV)负相关(r＝-0.415,P＝0.028),氧减指数与BNP正相关(rs＝0.409,P＝0.031),血氧饱和度低于90%的时间占总睡眠时间的比例(TST90)与肺动脉收缩压、TRV、BNP均呈正相关(rs＝0.505、0.584、0.455,P＝0.006、0.001、0.015),TST90与肺一氧化碳弥散量负相关(rs＝-0.458,P＝0.028)。二元Logistic回归分析显示,TST90与ILD重度肺间质病变有显著相关性(P＝0.036,OR＝1.025,95%CI＝1.002～1.049),TST90 1.8%为预测重度肺间质病变的最佳截断值,ROC分析曲线下面积为0.719(P＝0.013,95%CI＝0.564～0.875),敏感性为89.9%,特异性为53.6%。 结论睡眠间歇性低氧与ILD患者心肺功能、肺间质病变严重程度有一定相关性,TST90是ILD患者心肺功能差、肺间质病变程度重的独立相关性因素。     

The determinants of right ventricular function in patients with atrial septal defect

OBJECTIVE: The purpose of this study was to ascertain the determinants of right ventricular (RV) systolic and diastolic functions in patients with atrial septal defect. METHODS: Thirty-three patients with atrial septal defect having left to right shunt were enrolled in this study. RV function parameters were assessed echocardiographically. RV systolic function was assessed using tricuspid tissue Doppler S velocity (St). With regard to RV diastolic function parameters, E/A ratio, deceleration time (DT), E/Et ratio (Et = tissue Doppler E velocity), RV isovolumetric relaxation time (RVIVRT) were assessed. RV myocardial performance index (MPI) was calculated as an index of both systolic and diastolic function. Pulmonary artery stiffness (PAS) was also calculated. After echocardiography, right and left heart catheterization was performed. Mean pulmonary artery pressure (MPAP), mean right atrial pressure (MRAP), systemic flow (Qs), pulmonary flow (Qp), systemic vascular resistance (SVR), and pulmonary vascular resistance (PVR) were obtained using the data of invasive measurements. RESULTS: In multivariate analysis, MPAP was found to be the parameter closest related to RVIVRT (r = 0.73, p < 0.001) and E/Et (r = 0.66, p < 0.001), while PAS was found to be the parameter closest related to MPI (r = 0.53, p = 0.002). In addition, St velocity was found the only parameter related to PVR (r = -0.39) in univariate analysis. There was no relationship between QP/QS and any of the RV function parameters. CONCLUSION: The pulmonary vascular bed appears to be the predictor of the RV functions in patients with atrial left to right shunts, and the amount of the shunt seems to have no direct adverse influence on the RV functions.     

Impact of Pulmonary Artery Stiffness on Right Ventricular Function and Tricuspid Regurgitation after Successful Percutaneous Balloon Mitral Valvuloplasty: The Importance of Early Intervention

Aims: We assessed impact of pulmonary artery stiffness (PAS) on the long‐term right ventricular (RV) function and tricuspid regurgitation (TR) changes after percutaneous balloon mitral valvuloplasty (PBMV). Methods and Results: Using Doppler echocardiography, PAS was calculated by dividing maximal frequency shift of pulmonary flow by the acceleration time, and mitral area, RV function, and degree of TR severity were evaluated before, immediately after, 6 months, and 12 months after successful PBMV in 81 consecutive patients. Compared with control subjects patients with mitral stenosis (MS) had significant higher PAS (P < 0.001). The PAS was significantly lower in patients with progressive RV function improvement and regression of TR (P < 0.001). PAS was significantly correlated with the degree of pulmonary artery systolic pressure (PASP), tricuspid annular plane systolic excursion (TAPSE), and E/E'm ratio (P < 0.0001, <0.0001, and < 0.001, respectively). Multivariate regression analysis showed that the PAS is an independent predictor of TR regression and sustained RV functional improvement after successful PBMV (P < 0.0001). Conclusions: The changes in RV function and TR after successful PBMV were significantly correlated with the degree of PAS. Despite a sustained increase in mitral valve area, some patients showed no regression of TR, and progressive RV dysfunction suggests a significant role of PAS on RV function and the degree of TR regression in patients with MS suggests that PBMV must be performed early, utilizing PAS as a noninvasive parameter for proper timing for PBMV.     

Independent and additive prognostic value of right ventricular systolic function and pulmonary artery pressure in patients with chronic heart failure

OBJECTIVES: We sought a better understanding of the coupling between right ventricular ejection fraction (RVEF) and pulmonary artery pressure (PAP), as it might improve the accuracy of the prognostic stratification of patients with heart failure. BACKGROUND: Despite the long-standing view that systolic function of the right ventricle (RV) is almost exclusively dependent on the afterload that this cardiac chamber must confront, recent studies claim that RV function is an independent prognostic factor in patients with chronic heart failure. METHODS: Right heart catheterization was performed in 377 consecutive patients with heart failure. RESULTS: During a median follow-up period of 17 +/- 9 months, 105 patients died and 35 underwent urgent heart transplantation. Pulmonary artery pressure and thermodilution-derived RVEF were inversely related (r = 0.66, p < 0.001). However, on Cox multivariate survival analysis, no interaction between such variables was found, and both turned out to be independent prognostic predictors (p < 0.001). It was found that RVEF was preserved in some patients with pulmonary hypertension, and that the prognosis of these patients was similar to that of the patients with normal PAP. In contrast, when PAP was normal, reduced RV function did not carry an additional risk. CONCLUSIONS: These observations emphasize the necessity of combining the right heart hemodynamic variables with a functional evaluation of the RV when trying to define the individual risk of patients with heart failure.     

Early changes of cardiac structure and function in COPD patients with mild hypoxemia

BACKGROUND: COPD is often associated with changes of the structure and the function of the heart. Although functional abnormalities of the right ventricle (RV) have been well described in COPD patients with severe hypoxemia, little is known about these changes in patients with normoxia and mild hypoxemia. STUDY OBJECTIVES: To assess the structural and functional cardiac changes in COPD patients with normal Pa(O2) and without signs of RV failure. METHODS: In 25 clinically stable COPD patients (FEV1, 1.23 +/- 0.51 L/s; Pa(O2), 82 +/- 10 mm Hg [mean +/- SD]) and 26 age-matched control subjects, the RV and left ventricular (LV) structure and function were measured by MRI. Pulmonary artery pressure (PAP) was estimated from right pulmonary artery distensibility. RESULTS: RV mass divided by RV end-diastolic volume as a measure of RV adaptation was 0.72 +/- 0.18 g/mL in the COPD group and 0.41 +/- 0.09 g/mL in the control group (p < 0.01). LV and RV ejection fractions were 62 +/- 14% and 53 +/- 12% in the COPD patients, and 68 +/- 11% and 53 +/- 7% in the control subjects, respectively. PAP estimated from right pulmonary artery distensibility was not elevated in the COPD group. CONCLUSION: From these results, we conclude that concentric RV hypertrophy is the earliest sign of RV pressure overload in patients with COPD. This structural adaptation of the heart does not alter RV and LV systolic function.     

Aortic and pulmonary artery stiffness and cardiac function in children at risk for obesity

Objective: Childhood obesity is associated with cardiovascular risk factors. Being at risk for overweight has been defined as having a body mass index (BMI) between the 85th and 94th percentile for age and sex. In this study, we investigate the aortic and pulmonary artery stiffness and left and right ventricular function in children who are at risk for obesity Methods: Fifty-six children who were at risk for obesity (study group) and 40 children with a BMI between the 25th and 74th percentiles (controls) were studied. Fasting blood levels of glucose, total cholesterol, HDL cholesterol, triglycerides, and high sensitive C-reactive protein (CRP) were assessed in both groups. Left ventricular as well as right ventricular tissue Doppler was evaluated. Aortic and pulmonary artery stiffness (PAS) were a Results: Aortic stiffness and PAS were significantly increased in children who were at risk for obesity compared with control children (P < 0.001). The children who were at risk for obesity have subclinical left and right ventricular dysfunction (P < 0.001 and P < 0.001 for left and right isovolumetric relaxation time and <0.002 and 0.001 for left and right Tei index). The hs-CRP was significantly higher (P < 0.01) compared to controls. Waist circumference and hs-CRP (P < 0.001) were the main predictors of aortic and PAS. Conclusion: Children who were at risk for obesity have increased aortic and PAS, subclinical LV and RV dysfunction. These abnormalities were associated with increased hs-CRP. The data suggest that appropriate strategies for weight control are essential not only for obese children but also for those at risk for overweight.     

Mal-effects of obstructive sleep apnea on the heart

Objective

This study aims to examine the impact of chronic intermittent hypoxia on hearts in patients with obstructive sleep apnea (OSA).

Methods

Two hundred twenty patients were divided into groups based on (1) severity of the disease, (2) years of disease history, and (3) with or without secondary hypertension. All subjects underwent blood pressure measurements, polysomnogram monitoring, and cardiac Doppler ultrasound examinations.

Results

The left ventricular ejection fraction (LVEF), fractional shortening (FS), and the ratio of early to late diastolic filling (E/A) in patients with severe OSA were lower than in those with moderate OSA and in healthy controls. The inner diameters of the main pulmonary artery (inD of MPA), the inner diameters of the right cardiac ventricle (inD of RV), and the thickness of anterior wall of the right ventricle (TAW of RV) were increased in patients with severe OSA compared to those with moderate disease and worsened as a function of time with disease. The tissue Doppler imaging-derived Tei index and pulmonary artery systolic pressure were also increased along with the severity of OSA. LVEF and FS in patients who had suffered from OSA for >10?years were decreased compared with those suffering from OSA for a shorter time. LVEF and FS in patients with secondary hypertension were decreased significantly relative to non-hypertensive OSA patients and healthy controls. E/A was decreased in OSA patients whether they had secondary hypertension or not.

Conclusion

OSA affected the left ventricular diastolic function in the early stage of the disease. Extended exposure to OSA resulted in left ventricular dysfunction with increased hypertension. Right ventricle dysfunction and abnormalities became more severe as the disease progressed.     

Serum levels of vascular endothelial growth factor are elevated in patients with obstructive sleep apnea and severe nighttime hypoxia.

Obstructive sleep apnea (OSA) is associated with increased cardiovascular morbidity and mortality; however, some patients with OSA do not develop cardiovascular disease even in the presence of severe nocturnal oxygen desaturations. Vascular endothelial growth factor (VEGF) is a hypoxia-sensitive glycoprotein stimulating neoangiogenesis. We hypothesized that VEGF production is increased in OSA because of repetitive nocturnal hypoxia. Three different groups were investigated: 10 OSA patients with severe nighttime hypoxia (Group A), 10 OSA patients with moderate hypoxia (Group B), and 10 healthy volunteers (Group C). Serum levels of VEGF were measured by ELISA from peripheral venous blood samples obtained at 7 AM. Group A had significantly (p < 0.01) increased VEGF serum levels when compared with Group B and Group C (mean +/- SEM: 410 +/- 77 pg/ml versus 224 +/- 38 pg/ml and 245 +/- 61 pg/ml). The degree of nocturnal oxygen desaturation in OSA significantly correlated with the VEGF concentrations (r = 0.67, p < 0.01). In conclusion, serum levels of VEGF are elevated in severely hypoxic patients with OSA and are related to the degree of nocturnal oxygen desaturation. This might constitute an adaptive mechanism to counterbalance the emergence of OSA-related cardiovascular disease.     

New approaches to noninvasive assessment of pulmonary artery pressure

Direct measurement of pulmonary artery pressure (PAP) was performed in 36 patients; right ventricular (RV) isovolumic relaxation time (IRT) and RV systolic output acceleration time (AcT) values were assessed by pulsed Doppler and 2-M echocardiography. There was a fairly good correlation between RV IRT and systolic PAP (r = 0.898; SEE = 7.8 mmHg) and a somewhat weaker one between RV AcT and systolic PAP (r = -0.880; SEE = 8.37 mmHg). Correlation coefficients were the highest between systolic PAP and the [formula: see text] (r = 0.972; SEE = 4.14), and also between mean PAP and the 10-RV AcT/100 predictor: y = 158x + 6.7 (r = 0.951; SEE = 3.48 mmHg). With +/- 5 mmHg deviations, systolic PAP measurements were accurate in 78% and those of mean PAP in 98% of the patients. The double-blind assessment of the reproducibility of the suggested noninvasive PAP measurement was performed in 18 subsequent patients; the interstudy variability of the measurement was 0.88 +/- 0.94 mmHg and 1.22 +/- 1.23 mmHg (p > 0.05), whereas interobserver variability was 1.90 +/- 1.70 mmHg and 1.67 +/- 1.63 mmHg, respectively (p > 0.05). Thus, a combined use of the most informative intervals of RV cycle--IRT and AcT--contributes to the accuracy of noninvasive PAP measurement.