健康成人上腔静脉血流频谱特点的观察

目的探讨健康成人上腔静脉(SVC)血流频谱的特点及随呼吸运动的变化规律。方法健康成人志愿者均取平卧位,采用彩色多普勒超声仪经右侧锁骨上窝探测上腔静脉,记录平静呼吸时上腔静脉的频谱曲线,测量同一呼吸周期中频谱曲线各波峰值及速度时间积分(VTI),计算其呼吸变化率。结果经右锁骨上窝SVC长轴切面获取SVC多普勒图像较为清晰。所有所得SVC血流频谱中,S波与D波的波幅均远大于心室收缩期反向波VR波和心房收缩期反向波AR波。平静呼吸时上腔静脉频谱主波变化明显(P<0.05),吸气时增大,呼气时减小(P<0.05),整个呼吸周期S波峰值大于D波,VR波与AR波变化不明显(P>0.05)。主波速度时间积分的呼气相变化率小于吸气相变化率,差异明显(P<0.05),D波速度时间积分的呼气相及吸气相变化率大于S波的变化率(P<0.05)。结论经右锁骨上窝探测SVC血流频谱可获得清晰图像,自主呼吸对SVC血流频谱形态及各波峰参数有一定影响。     

健康成人上腔静脉血流频谱特点的观察

目的探讨健康成人上腔静脉（SVC）血流频谱的特点及随呼吸运动的变化规律。方法健康成人志愿者均取平卧位，采用彩色多普勒超声仪经右侧锁骨上窝探测上腔静脉，记录平静呼吸时上腔静脉的频谱曲线，测量同一呼吸周期中频谱曲线各波峰值及速度时间积分（VTI），计算其呼吸变化率。结果经右锁骨上窝svc长轴切面获取svc多普勒图像较为清晰。所有所得svc血流频谱中，S波与D波的波幅均远大于心室收缩期反向波VR波和心房收缩期反向波AR波。平静呼吸时上腔静脉频谱主波变化明显（P〈0．05），吸气时增大，呼气时减小（P〈O．05），整个呼吸周期S波峰值大于D波，VR波与AR波变化不明显（P〉0．05）。主波速度时间积分的呼气相变化率小于吸气相变化率，差异明显（P〈0．05），D波速度时间积分的呼气相及吸气相变化率大于s波的变化率（P〈0．05）。结论经右锁骨上窝探测SVC血流频谱可获得清晰图像，自主呼吸对SVC血流频谱形态及各波峰参数有一定影响。     

健康成人上腔静脉血流频谱特点的观察

目的 探讨健康成人上腔静脉(SVC)血流频谱的特点及随呼吸运动的变化规律.方法 健康成人志愿者均取平卧位.采用彩色多普勒超声仪经右侧锁骨上窝探测上腔静脉,记录平静呼吸时上腔静脉的频谱曲线.测量同一呼吸周期中频谱曲线各波峰值及速度时间积分(VTI),计算其呼吸变化率.结果 经右锁骨上窝SVC长轴切面获取SVC多普勒图像较为清晰.所有所得SVC血流频谱中,S波与D波的波幅均远大于心室收缩期反向波VR波和心房收缩期反向波AR波.平静呼吸时上腔静脉频谱主波变化明显(P＜0.05),吸气时增大,呼气时减小(P＜0.05),整个呼吸周期S波峰值大于D波,VR波与AR波变化不明显(P＞0.05).主波速度时间积分的呼气相变化率小于吸气相变化率,差异明显(P＜0.05),D波速度时间积分的呼气相及吸气相变化率大于S波的变化率(P＜0.05).结论 经右锁骨上窝探测SVC血流频谱可获得清晰图像,自主呼吸对SVC血流频谱形态及各波峰参数有一定影响.     

健康新西兰兔上腔静脉的二维超声及多普勒血流频谱分析

目的 利用二维、彩色及频谱多普勒超声对健康新西兰兔上腔静脉(SVC)内径及血流频谱进行分析,探讨其正常值范围。 方法 健康成年新西兰兔84只,经双侧锁骨上窝切面显示SVC长轴,同步连接呼吸曲线及心电图,获取SVC管腔内径及血流频谱,分析双侧SVC内径及多普勒血流频谱。 结果 经锁骨上窝SVC长轴切面获取其二维、彩色及多普勒图像成功率为100%。二维超声测量吸气末右侧SVC内径[(0.29±0.06)cm]大于左侧SVC内径[(0.20±0.04)cm,P＜0.01]。频谱多普勒显示S波、D波的血流速度峰值吸气相较呼气相增高(P＜0.01);VR波、AR波的血流速度峰值吸气相与呼气相相比差异无统计学意义(P均＞0.05)。 结论 经锁骨上窝长轴切面能获得较满意的SVC二维、彩色及频谱多普勒图像;兔双侧SVC的内径存在差异;兔SVC的血流频谱随呼吸周期呈规律性变化。     

上腔静脉综合征患者的上腔静脉多普勒血流频谱分析

目的 :利用多普勒超声观察上腔静脉综合征 (SVCS)患者上腔静脉 (SVC)血流频谱形态变化 ,探讨其频谱特征。方法 :对 48例 SVCS患者和 42例健康志愿者经右锁骨上窝及心尖五腔切面行多普勒超声检查。使用仪器为 Acuson XP/10及 Sequoia512彩色电脑声像仪 ,同步连接心电图及呼吸信号记录仪。结果 :48例 SVCS患者外压型 3 8例 ,腔内型 9例 ,其它 1例。外压型因狭窄程度不同 ,SVC频谱形态及血流速度不同 ,14例外压伴轻度狭窄者 SVC频谱呈全填充状 ,但 S波、D波清晰可辨 ;19例外压伴中度狭窄者频谱呈宽带、连续性、全填充状 ,收缩期S波、舒张期 D波难以分辨 ;5例外压伴重度狭窄及 9例腔内型者 ,血流频谱均呈低幅宽带、连续性、全填充状频谱。外压伴轻中度狭窄、伴重度狭窄时 SVC峰值速度分别为 (198.0± 2 6.0 9) cm/s,(2 5.3 4± 19.47) cm/s(与对照组比较 P=0 .0 0 0 )。腔内型血流速度为 (16.4± 6.91) cm/s(与对照组比较 P=0 .0 0 0 )。其它 1例为 SVC术后瘢痕性狭窄 ,SVC血流速度加快。 48例患者平静呼吸状态下 ,SVC血流频谱峰值速度受呼吸运动影响减小。结论 :不同原因及狭窄程度的 SVCS其频谱形态及流速在心动周期及呼吸周期中表现不同 ,该特征性变化为超声诊断 SVCS提供重要依据。     

多普勒超声评价兔上腔静脉阻塞血流动力学变化的实验研究

目的应用多普勒超声技术研究实验性兔VX2肿瘤性上腔静脉阻塞(SVCO)时,上腔静脉(SVC)的血流动力学变化,探讨多普勒血流频谱特征.方法在超声引导下将VX2瘤组织悬液接种到SVC前壁前部的软组织内,建立SV-CO动物模型.对14只实验兔于接种后12天,每隔2天经右锁骨上窝切面超声检测SVC血流变化,测量相关指标,并与接种前的超声测值比较.结果随着肿瘤生长对SVC产生压迫,SVC受压和/或破坏,彩色多普勒显示SVC腔内逐渐出现五彩加速血流,至病变晚期血流信号反而减弱;频谱多普勒记录到病变早中期S波、D波血流速度分别为(78.25±14.97)cm/s、(59.68±13.16)cm/s,晚期各波速度分别为(33.71±15.90)cm/s、(33.55±20.03)cm/s.与晚期比较,在早中期SVC各波速度加快(P＜0.001).结论兔SVCO时SVC彩色及频谱多普勒呈现典型狭窄图像,其多普勒图像特征与临床SV-CO有较好的一致性.     

正常成人颈内静脉多普勒血流频谱分析

目的　利用多普勒超声对正常成人不同年龄段颈内静脉血流动力学进行分析 ,探讨其血流频谱变化与呼吸、心动周期的关系。方法　对随机选取的 12 0名成年健康志愿者沿颈总动脉外侧探测颈内静脉 ,在二维切面的基础上获取其血流频谱 ,测定不同心动周期及呼吸周期中颈内静脉血流动力学指标。结果　在心动周期中 ,颈内静脉血流频谱呈现收缩期S波、舒张期D波和舒张期A波 ;在平静呼吸状态下 ,受检者吸气相和呼气相S波速率分别为 (2 7.17± 19.88)cm/s、(19.0 4± 14 .2 6)cm/s ,D波速率分别为(17.43± 12 .78)cm/s、(12 .70± 10 .57)cm /s ,吸气相速率较呼气相速率快 (均P <0 .0 0 1) ,呼吸周期中A波速率无明显变化 [(6.3 8± 6.3 2 )cm/s、(7.59± 7.42 )cm /s,P >0 .0 5] ;60岁以上组S和D波血流速率较 2 0～ 60岁组血流速度低 (P <0 .0 5)。结论　正常颈内静脉血流频谱由 3个波组成 ,频谱形态随心动周期、呼吸周期呈规律性变化 ;年龄因素影响颈内静脉多普勒血流速率 ;建立了正常成人颈内静脉多普勒血流速率参数的正常值     

呼吸运动对健康成年人上腔静脉多普勒频谱影响研究

目的 探讨健康成年人上腔静脉（SVC）频谱各波峰值及速度时间积分（VTI）随生理呼吸变化的规律。方法 经右侧锁骨上窝切面探查44名健康成年人的SVC,记录呼吸周期中SVC主波流速最大的频谱曲线和流速最小的频谱曲线各波峰值及VTI,计算各波峰值及VTI随呼吸的最大变化率,结果 用统计软件Spss11．0行多组均数差别多重比较的方差分析。结果 健康成年人SVC频谱各波峰值及VTI随生理呼吸的变化有一定的规律：S波与D波之间、VR波与AR波之间峰值速度的吸气变化率（ICR）及呼气变化率（ECR）无显著差异（P〉0．05）。S波、D波峰值速度ICR大于ECR（P〈0．05）;VR波、AR波峰值速度的ECR与ICR无显著差异（P〉0．05）。S波与D波之间VTI的ECR与ICR差异显著（P〈0．05）,D波VTI的ICR及ECR均比S波大;VR波、AR波的VTI之间差异显著（P〈0．05）,AR波ICR大于VR波,VR波ECR大于AR波。S波、D波、AR波VTI的ICR均大于ECR（P〈0．05）,VR波VTI的ECR大于ICR（P〈0．05）。结论 健康成年人SVC频谱各波峰值及VTI随生理呼吸出现规律性变化,对这种变化规律的认知,有助于SVC超声检查临床应用价值的深入研究。     

正常成年人上腔静脉的二维超声检测

目的探讨上腔静脉(SVC)最佳超声检测途径,获取较客观的SVC形态学指标。方法对随机选取的56例健康志愿者行经右锁骨上窝及心尖五腔、剑下四腔切面基础上的SVC超声探查,测量平静呼吸状态下各切面SVC内径及可见长度。结果56例受试者右锁骨上窝、胸骨旁心尖五腔及剑下四腔切面SVC显示率分别是,96.43%、89.3%、82.1%,显示长度分别是(56.49±7.91)mm、(28.29±5.83)mm、(22.05±4.37)mm。吸气相内径分别是(16.00±2.11)mm、(13.71±2.34)mm、(11.43±2.05)mm,呼气相内径分别是(9.41±1.63)mm、(8.91±1.78)mm、(6.61±1.14)mm。结论右锁骨上窝切面及心尖五腔切面SVC显示满意率较高,可对SVC行全程检测。SVC内径随呼吸周期呈规律性变化。     

平静呼吸对肺静脉血流的影响及其机制的超声心动图研究

目的 研究平静呼吸对肺静脉血流的影响及其规律，进一步验证呼吸影响心功能机制新假说，探讨肺静脉血流速度随呼吸变化对评价左心室舒张功能潜在的意义。方法 20名健康志愿者，采用Sequoia 512超声仪，同步记录右上肺静脉血流速度频谱、心电图和呼吸曲线。连续测量5个呼吸周期吸气相和呼气相血流速度及速度时间积分（VTI），取平均值。分别计算吸气相和呼气相肺静脉收缩期S波与舒张期D波的速度比值以及VTI比值。结果 肺静脉收缩期S波血流速度及VTI于吸气相和呼气相之间变化不显著（P=0．221；P=0．090）；舒张期D波血流速度及VTI在吸气相低于呼气相（均P〈0．001）；S波与D波血流速度比值及VTI比值在吸气相高于呼气相（均P〈0．001）。结论 平静呼吸对肺静脉血流影响具有规律性：S波血流速度及VTI于吸气相和呼气相之间变化不显著；D波血流速度及VTI在吸气相低于呼气相；S波与D波血流速度比值及VTI比值在吸气相高于呼气相，其中血流速度比值在吸气相〉1，而在呼气相可〉1，也可≤1。进一步验证了呼吸影响心功能机制新假说。利用肺静脉频谱评价左室舒张功能时如能结合呼吸的影响则可能提供更多信息。     

健康成年新西兰兔肺动脉、肺静脉血流频谱分析及右心系统压力检测

目的 利用超声心动图及右心导管测量新西兰兔肺动脉、肺静脉频谱指标及右心系统压力指标,了解其频谱特点及右心系统压力的正常值范围。 方法 选择健康成年新西兰兔24只,用彩色多普勒超声诊断系统测量其肺动脉、肺静脉频谱,并同步记录心电图及呼吸曲线。通过右心导管记录并测量其右心房、右心室、肺动脉的收缩压及舒张压。 结果 频谱多普勒结果显示新西兰兔肺静脉频谱的峰值血流速度吸气相与呼气相的差异均无统计学意义(P均>0.05),肺动脉频谱峰值血流速度吸气相高于呼气相,差异有统计学意义(P<0.001)。右心导管压力测值结果显示新西兰兔肺动脉收缩压范围为16.07~23.99 mmHg、肺动脉舒张压为11.18~19.22 mmHg。 结论 超声心动图可清晰显示新西兰兔肺动脉、肺静脉血流;其肺动脉血流频谱随呼吸周期呈规律性变化。     

呼吸对右心衰竭患者三尖瓣反流速度和肺动脉压测定的影响

目的 探讨平静呼吸对右心衰竭患者三尖瓣反流速度和肺动脉收缩压测定的影响.方法 选取32例右心衰竭患者(病例组)和28例右心功能正常而三尖瓣反流患者(对照组)行超声心动图检查.观测三尖瓣反流速度,根据反流法计算肺动脉收缩压,比较两组吸气相与呼气相之间的差异.结果 病例组三尖瓣反流速度、肺动脉收缩压吸气相均小于呼气相(P＜0.001);对照组三尖瓣反流速度、肺动脉收缩压吸气相与呼气相比较差异无统计学意义.结论 使用超声心动图估测肺动脉收缩压时,应注意平静呼吸对右心衰竭患者三尖瓣反流速度和肺动脉收缩压测定的影响,尽量在呼气末或呼气末屏气状态下进行.     

Reversal of the pattern of respiratory variation of Doppler inflow velocities in constrictive pericarditis during mechanical ventilation.

BACKGROUND: Spontaneous inspiration causes a characteristic decrease of the mitral valve (MV) and pulmonary venous (PV) flow velocities obtained by Doppler echocardiography in patients with constrictive pericarditis (CP). This has been explained by the decrement it causes in the intrathoracic pressure. Positive pressure ventilation (PPV) causes an increment of intrathoracic pressure with mechanical inspiration. Therefore the pattern of respiratory variation produced during PPV may differ from that seen during spontaneous breathing. OBJECTIVE: Our goal was to describe the effect of PPV on the pattern and magnitude of respiratory variation of MV and PV flow velocities in CP. METHODS: We performed intraoperative pulsed Doppler transesophageal echocardiography on 15 patients (13 men, mean age 52+/-15 years) with CP after general anesthesia and before sternotomy and pericardial stripping. The peak velocity and time-velocity integral (TVI) of the mitral inflow E and A waves and the PV systolic and diastolic waves were measured at onset of inspiration and expiration for 3 to 6 respiratory cycles. Respiratory phase was monitored with a heat-sensitive nasal thermistor. The percent change in Doppler flow velocities from mechanical inspiration (INS) to mechanical expiration (EXP) was calculated with the formula %change = INS - EXP / INS x 100. RESULTS: The peak velocity of the mitral inflow E wave was significantly higher during mechanical inspiration than expiration (57 +/-14.5 versus 47+/-13.9 cm/s, P<.001). This represented a percent change of 18%+/-7.9% from expiration to inspiration. The mean TVI of the mitral inflow E was also higher during mechanical inspiration than expiration (P = .02). The peak velocity of the PV D wave was higher during mechanical inspiration than expiration (39+/-17.8 versus 28+/-14.7 cm/s, P<.001). This represented a mean percent change of 28%+/-13.8%. The mean value of the TVI for the PV D wave was also significantly greater during mechanical inspiration than expiration (P <.05). CONCLUSIONS: Positive pressure ventilation reverses the pattern of respiratory variation of the MV and PV flow velocities in CP. The percent change in the peak velocities of the MV and PV flows produced by PPV is the same range reported in CP during spontaneous breathing.     

Effect of respiration on the spectral Doppler wave of the right hepatic vein in right lobe living donor liver transplant recipients.

OBJECTIVE: The purpose of this study was to evaluate the effect of respiration on the spectral Doppler wave of the right hepatic vein (RHV) in right lobe living donor liver transplant (LDLT) recipients. METHODS: A spectral Doppler wave of the RHV was obtained from 23 consecutive right lobe LDLT recipients who had no complications and from 26 healthy subjects during free breathing, breath holding at expiration, and breath holding at inspiration. To assess the RHV flow quantitatively, the venous periodicity index (VPI) was calculated as follows: VPI=(V(F)-V(R))/V(F), where V(F) was the measured peak forward velocity, and V(R) was the measured peak reversed velocity. The mean VPIs of the RHV obtained in the 3 respiratory states were compared by repeated measures analysis of variance. Spectral Doppler waves of the RHV were categorized as triphasic with or without reversed flow, biphasic, or monophasic and were compared among the 3 respiratory states. RESULTS: In both right lobe LDLT recipients and healthy subjects, the mean VPIs of the RHV obtained during breath holding at inspiration were significantly lower than those during free breathing (P<.001) and breath holding at expiration (P<.001). The wave pattern during breath holding at inspiration was monophasic in 7 (30.4%) right lobe LDLT recipients and 3 (11.5%) healthy subjects, whereas the monophasic pattern was not seen during free breathing or breath holding at expiration in any of these subjects. CONCLUSIONS: Breath holding at inspiration significantly reduces the periodicity of RHV flow and can make otherwise pulsatile RHV flow monophasic in right lobe LDLT recipients without postoperative complications as well as in healthy individuals.     

Doppler systemic venous flow patterns: Changes in children with mild/moderate pulmonic stenosis

To determine the usefulness of systemic venous flow patterns in patients with mild/moderate right ventricular hypertension, 17 patients with isolated mild/moderate pulmonic stenosis and 17 age-matched normal children were evaluated with pulsed Doppler echocardiography. Tricuspid valve, superior vena caval, and hepatic vein pulsed Doppler recordings were obtained with simultaneous respirometry and electrocardiography. Peak velocities and velocity-time integrals were measured for Doppler signals corresponding with ventricular systole, ventricular diastole, ventricular end systole, and atrial systole. The groups were similar in weight, heart rate, tricuspid inflow Doppler echocardiograms, and cardiac indexes. Compared with normal subjects, patients showed changes in respiratory variation for some superior vena caval and hepatic vein indexes. In addition, hepatic vein measurements made at ventricular end systole were significantly lower and measurements made at atrial systole were significantly higher in patients than in normal subjects. These changes in systemic venous flow patterns may provide a sensitive indicator of early right-sided heart dysfunction.     

模拟低血容量对健康青年男性上腔静脉及三尖瓣血流速度的影响

目的探讨上腔静脉及三尖瓣血流速度曲线中各波速度及其相关比值在评价容量反应性中的应用价值。方法用超声心动图方法记录16名健康青年男性在模拟低血容量情况[最大-60mmHg（1mmHg=0．133kPa）的阶梯式递增下体负压作用]下上腔静脉及三尖瓣的流速曲线，测量各波速度，计算其相关比值，并进行统计学分析。结果下体负压作用下，上腔静脉流速曲线中的心室收缩波和心房收缩反向波速度与下体负压水平有较好的相关性，相关系数分别为-0．744和-0．771，P〈0．001。结论上腔静脉流速曲线中心室收缩波和心房收缩反向波速度在评价容量反应性中有一定应用价值。