Valsalva动作鉴别二尖瓣舒张期血流频谱假性正常

目的探讨做Valsalva动作是否可以鉴别假性正常的二尖瓣口舒张期血流频谱。方法在平静时二尖瓣口舒张期血流频谱形态正常的对照组33例,年龄(61.4±9.9)岁和可能为假性正常的心肌缺血组19例(其中8例为经冠状动脉造影证实为一支以上冠状动脉主支近端狭窄＞75%,11例为陈旧性心肌梗塞,年龄(63.1±9.5)岁,比较两组在做Valsalva动作时的二尖瓣口舒张期血流频谱的E、A峰峰值流速,E/A,E峰减速时间(DT)和等容舒张期(IVRT)的变化。结果平静时两组间E、A、E/A和DT均无显著差异。假性正常组的IVRT略大于正常组(93±9)cm/s比(89±12)cm/s,P＜0.05。做Valsalva动作时,两组E、A峰均降低,正常组E峰减低幅度小于假性正常化组(－22±11)cm/s比(－30±9)cm/s,P＜0.01,而其A峰减低幅度大于假性正常化组(－9±14)cm/s比(－2±9)cm/s,P＜0.05,两组E/A出现显著差别,1.3±0.2比0.9±0.2,P＜0.01;两组DT(24±47)ms比(31±52)ms,P＝NS、IVRT(11±11)ms比(13±15)ms,P＝NS,变化幅度相近。结论做Valsalva动作,可以使二尖瓣口舒张期血流频谱正常组和假性正常组E、A、E/A发生不同的变化,可以用于两者鉴别。     

二尖瓣环运动斜率鉴别二尖瓣口舒张期血流频谱假性正常的临床研究

目的:探讨二尖瓣环运动斜率是否可以鉴别假性正常的二尖瓣口舒张期血流频谱。方法:二尖瓣口舒张期血流频谱形态正常的对照组25例,年龄(58.4±11.2)岁与彩超检查二尖瓣口舒张期血流频谱可能为假性正常,临床提示心肌缺血高度可疑左室舒张功能减退组23例(其中13例经冠状动脉造影证实一支以上冠状动脉主支近端狭窄>75％,10例为陈旧性心肌梗),年龄(64.1±8.6)岁的两组进行比较在四腔心切面上二尖瓣环舒张早期的运动斜率(Es),舒张晚期的运动斜率(As)及二者之比值(Es/As)。结果:两组间二尖瓣环在舒张早期,舒张晚期的运动斜率及二者之比值存在显著差异。假性正常组的舒张早期的运动斜率(Es),小于正常对照组(41±7.77)mm/s比(59±19.65)mm/s,P<0.05。舒张晚期的运动斜率(As)大于正常对照组(55±12.9)mm/8比(41±14.2)mm/s,P<0.05;而(Es/As)小于正常对照组(0.76±0.11)比(1.44±0.19),P<0.01。结论:用M型超声检测二尖瓣环舒张早期,舒张晚期的运动斜率及二者之比值可以鉴别二尖瓣口舒张期血流频谱假性正常。     

平静呼吸对正常人心内血流速度影响的超声心动图研究

目的　研究呼吸对心脏血流动力学的影响 ,为建立我国正常人呼吸性血流速度波动指数 (RVI)提供参考 ,验证呼吸影响心功能新假说。方法　 79名健康志愿者 ,采用AcusonSequoia 5 12和 12 8XP/10彩色电脑声像仪 ,记录各瓣口血流速度、同步心电图和呼吸曲线。不同呼吸相所测的各瓣口血流速度分别取平均值 ,计算RVI。结果　二尖瓣E峰血流速度和主动脉瓣血流速度在呼气相均高于吸气相 [( 83.79± 17.74)cm/svs ( 76.5 5± 15 .5 0 )cm/s ,P <0 .0 0 0 1;( 10 9.36± 14 .0 9)cm /svs ( 10 4.2 2± 13.75 )cm/s ,P <0 .0 0 0 1] ;三尖瓣E峰血流速度和肺动脉瓣血流速度在吸气相高于呼气相 [( 62 .19± 17.2 1)cm/svs ( 5 2 .79± 14 .10 )cm/s ,P <0 .0 0 0 1;( 89.80± 15 .78)cm/svs ( 84.76± 15 .0 3)cm /s ,P <0 .0 0 0 1]。二、三尖瓣 ,主、肺动脉瓣的RVI均值分别为8.39%、16.40 %、4.71%和 5 .73%。结论　平静呼吸对心脏血流动力学影响具有规律性。RVI可作为评定呼吸影响心功能的客观指标 ,为呼吸影响心功能假说提供了临床实验依据     

心肌组织多普勒技术结合M型超声评价急性下壁及前壁心肌梗死的右心室功能

目的　应用心肌组织多普勒 (TDI)技术结合M型超声测定三尖瓣环运动评价急性下壁及前壁心肌梗死 (心梗 )患者右心室整体功能。方法　正常对照组 2 5例 ,急性下壁心梗 2 5例 ,急性前壁心梗 2 3例。在标准心尖四腔心观二维图像指引下 ,采用M型超声记录三尖瓣环右室游离壁处运动曲线 ,测量收缩期、舒张早晚期运动幅度 ,采用TDI的频谱多普勒技术记录该处速度曲线 ,测量各期最大运动速度。结果　与对照组相比 ,急性下壁与前壁心梗患者三尖瓣环右室游离壁处收缩期及舒张早期运动幅度显著降低 ,最大收缩速度在下壁心梗显著降低 [(12 .9± 2 .7)cm /svs (15 .9± 2 .6)cm/s ,P <0 .0 1] ,在前壁心梗无下降 [(14 .5± 4.0 )cm/svs (15 .9± 2 .6)cm /s ,P >0 .0 5 ] ,两者舒张早期速度均显著降低 ,分别为 (12±3 .1)cm/s和 (13 .2± 3 .1)cm/s ,舒张早期与晚期速度比值也明显降低。结论　TDI频谱多普勒技术能反映急性心梗导致的右室舒缩功能减低 ,其与M型超声结合测定三尖瓣环运动有利于全面评价心梗后右室整体功能。     

彩色室壁运动技术定量评价陈旧心肌梗塞左室舒张功能

目的: 应用彩色室壁运动技术(CK) 定量评价存在收缩功能异常的陈旧心肌梗塞患者的左室局部和整体舒张功能。方法: 19 例心肌梗塞患者 (左室射血分数: 34.9±5.89% ) 和21 例正常人进行了CK 检测, 同时记录二尖瓣血流频谱。CK 测量参数: 左室壁各节段全舒张期及前1/3 舒张期心内膜位移(DEM, 1/3DEM), 前1/3 舒张期心内膜位移分数 (1/3DEMF); 全舒张期、前1/3 及后2/3 舒张期心内膜位移平均速度 (VDEM, 1/3 VDEM , 2/3VDEM)。二尖瓣血流频谱主要记录1/3 充盈分数 (1/3FF)。根据二维定性方法对运动正常、运动减弱和运动消失三种室壁运动状态CK 测量。结果: 运动正常节段: DEM8.89±1.21m m , VDEM2.30±0.76cm /s; 运动减弱节段: DEM4.56±0.53m m , VDEM1.89±0.35cm /s; 运动消失节段: DEM2.13±0.45m m , VDEM0.95±0.07cm /s; 三种不同室壁运动状态间的DEM、VDEM均存在显著性差异 (P< 0.0001)。运动正常节段的1/3VDEM 显著快于2/3VDEM (4.56±1.18cm /s vs 1.26±0.34cm /s, P< 0.0001); 运动减弱节段的1/3 VDEM 略快于2/3VDEM (2.14±0.66cm /s vs 1.76±0.47cm /s, P< 0.05); 而运动消失节段的1/3 VDEM显著低于2/3 VDEM (1.23±0.52cm /s vs 1.37±0.30cm /s, P<0.0001)。正常组的1/3FF和1/3DEMF (r=     

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     

冠状动脉血流与左室舒张功能关系的临床研究

目的:探讨冠状循环血流动力学改变与左室舒张功能的关系。方法:采用经胸和经食管超声心动图技术,测量15例正常人、10例冠心病人、20例左室心肌肥厚患者冠状动脉前降支血流频谱、二尖瓣和肺静脉血流频谱。结果:与正常对照组比较,冠心病组冠脉血流频谱舒张期峰值流速(PDV)和每分钟流量(Q)无差异,PDV和Q与左室舒张功能指标无相关性;左室心肌肥厚组PDV和Q明显增加(62.57±23.79cm/s vs 35.80±9.40cm/s,P<0.001;97.92±59.24ml/min vs 46.02±23.11ml/min,P<0.01),Q与二尖瓣血流频谱E/A比值负相关(r=-0.49,P<0.01),与肺静脉血流频谱R正相关(r=0.41,P<0.05)。结论:左室心肌肥厚患者静息时冠脉血流量增加,可能是心肌肥厚患者左室舒张功能减低的机理之一。     

血管内多普勒超声对Budd-Chiari综合征血流动力学障碍的研究

目的　研究Budd Chiari综合征 (BCS)患者血流动力学 (压力、血流速度及血流量 )障碍及其与正常对照的差异。方法　使用血管内多普勒导丝对 2 7例BCS患者下腔静脉 (IVC)和 (或 )肝右静脉 (RHV )介入治疗(PTA)前后血流速度及血流量的变化进行检测 ,并以 10例正常人的相应数据作为对照。结果　PTA前 ,BCS患者RHV和IVC的平均峰值流速 (APV)明显低于正常组 [RHV :( 5 .0 5± 3.6 9)cm/svs ( 14 .73± 4.5 2 )cm/s ,P <0 .0 0 1;IVC :( 3.0 2± 6 .87)cm /svs ( 2 3.6 7± 5 .38)cm /s ,P <0 .0 0 1]。PTA后 ,BCS患者APV显著增加至正常 ,但与对照组比较差异无显著性意义 [IVC :( 2 4.83± 11.34)cm /svs ( 2 3.6 7± 5 .38)cm/s ,P >0 .1;RHV :( 16 .13± 10 .5 6 )cm /svs ( 14 .73± 4.5 2 )cm/s ,P >0 .1) ] ;而血流量增加更明显 ,和对照组比较差异有显著性意义 [IVC :( 4 914 .79± 937.5 2 )ml/minvs ( 385 6 .96± 376 .92 )ml/min ,P <0 .0 1;RHV :( 90 2 .6 3± 5 12 .37)ml/minvs( 6 13.0 3± 2 0 8.5 6 )ml/min ,P <0 .0 1) ]。结论　BCS存在严重的血流动力学紊乱状态 ,PTA后IVC、RHV血流动力学指标大致恢复正常。     

弥漫性颅内压升高患者经颅多普勒超声频谱与参数的变化

目的:观察弥漫性颅内高压患者的经颅多普勒超声(TCD)频谱和参数的变化.方法:对66例弥漫性颅内高压患者进行TCD检测,同时测血压并腰穿测颅内压.结果:颅内压升高时,出现典型的TCD频谱(高阻力血流频谱、舒张期血流消失频谱).随着颅内压升高,舒张末期血流速度减慢(16.39±3.56)cm/s,血管脉动指数(2.25±0.45)及阻力指数(0.89±0.098)增大,与正常对照组比较差异有显著性(P＜0.05).颅内高压治疗后,舒张末期血流速度升高(26.36±4.26)cm/s,血管脉动指数(1.15±0.23)及阻力指数(0.62±0.088)降低,与治疗前及正常对照组比较差异有显著性(P＜0.05).结论:根据特征性TCD频谱和参数改变可间接推断颅内压变化.     

平静呼吸对左室充盈的影响及其机制的超声心动图研究

目的研究平静呼吸对二尖瓣血流的影响及其规律,进而探讨呼吸对左室充盈的影响,进一步验证呼吸影响心功能机制新假说。方法20例健康志愿者,同步记录二尖瓣血流速度曲线、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二尖瓣舒张早期E波与舒张晚期A波的血流速度比值以及VTI比值。结果二尖瓣舒张早期E波血流速度及VTI在吸气相低于呼气相(84.28cm/s±15.16cm/s,92.45cm/s±15.96cm/s,P<0.0001;16.27cm±3.70cm,17.73cm±3.91cm,P<0.0001);舒张晚期A波血流速度及VTI在吸气相低于呼气相(51.61cm/s±9.86cm/s,54.21cm/s±11.27cm/s,P<0.0001;9.86cm±1.55cm,10.48cm±2.00cm,P<0.0001);E波与A波的血流速度比值及VTI比值在吸气相低于呼气相(1.69±0.47,1.78±0.52,P=0.001;1.68±0.43,1.75±0.47,P=0.003)。结论平静呼吸对二尖瓣血流影响具有规律性:E波血流速度及VTI、A波血流速度及VTI、E波与A波血流速度比值及VTI比值均在吸气相低于呼气相。在利用二尖瓣血流频谱评价左室充盈时如能结合呼吸变化,则能提供更多信息。进一步验证了呼吸影响心功能机制新假说。     

Assessment of left ventricular systolic and diastolic function by Doppler tissue imaging in patients with preinfarction angina.

BACKGROUND: The aim of this study was assessment of left ventricular (LV) systolic and diastolic function by pulsed wave Doppler tissue imaging (DTI) in patients with or without preinfarction angina in acute myocardial infarction. METHODS: We prospectively evaluated 31 consecutive patients (4 women, 27 men; age 58 +/- 10 years) with a first acute myocardial infarction. LV systolic and diastolic function was assessed by classic methods and DTI on the third day during acute myocardial infarction. Patients were divided into 2 groups according to the presence (group 1; n = 10) or absence (group 2; n = 21) of preinfarction angina. Mitral inflow velocities and early diastolic mitral annular velocity (Em), late diastolic mitral annular velocity (Am), peak systolic mitral annular velocity, Em/Am, the ratio of early diastolic mitral inflow velocity (E) to Em, and myocardial performance index were calculated by DTI. RESULTS: Group 1 had significantly higher Em and Em/Am than group 2 (11.3 +/- 3.34 cm/s vs 7.4 +/- 2.07 cm/s, P <.0001; 1.01 +/- 0.38 cm/s vs 0.6 +/- 0.2 cm/s, P =.001, respectively). The E/Em ratio and myocardial performance index were significantly lower in group 1 than in group 2 (5.1 +/- 2.92 vs 8.10 +/- 3.15, P=.018; 0.49 +/- 0.15 vs 0.65 +/- 0.24, P =.042, respectively). Wall-motion score index was lower in those with preinfarction angina than in those without (1.6 +/- 0.36 vs 1.9 +/- 0.39; P =.04, respectively). Peak systolic mitral annular velocity and Am were not statistically different between groups (9.4 +/- 1.84 vs 8.3 +/- 2.03, P =.172; 11.7 +/- 3.07 vs 12.1 +/- 3.34, P =.72, respectively). There were no significant differences between the 2 groups regarding transmitral E velocity, atrial contraction mitral inflow velocity (A), E/A ratio, isovolumetric relaxation time, and deceleration time of the mitral E wave (P =.91, P =.08, P =.58, P =.81, and P =.71, respectively). CONCLUSION: LV diastolic function was better in patients with preinfarction angina than in patients without. This condition could not be detected by conventional mitral inflow Doppler velocities, but could be detected by DTI. This preliminary evidence shows that DTI is better than conventional mitral Doppler indices in the assessment of a favorable LV diastolic function in patients with preinfarction angina.     

Usefulness of early diastolic flow propagation velocity measured by color M-mode Doppler technique for the assessment of left ventricular diastolic function in patients with hypertrophic cardiomyopathy.

Flow propagation velocity (FPV) of left ventricular (LV) filling flow has been shown to be a useful index for the evaluation of LV diastolic function, which is relatively independent of preload in myocardial infarction and dilated cardiomyopathy, but the usefulness of FPV for hypertrophic cardiomyopathy (HCM) has not yet been determined. In 23 HCM patients and 26 control subjects, peak transmitral flow velocities in early diastole (E) and during atrial contraction (A), E/A ratio, deceleration time of E velocity, and isovolumic relaxation time were measured with the conventional Doppler technique, and FPV was measured from color M-mode Doppler images of LV filling flow. The time constant of LV isovolumic pressure decay (tau) was measured by a micro-manometer-tipped catheter in all HCM patients and 13 control subjects. Flow propagation velocity was significantly lower and deceleration time was significantly greater in HCM patients than in the control subjects, though no significant differences were observed in the other noninvasive indexes. Tau was significantly prolonged in HCM patients compared with that of control subjects (54+/-12 cm/s and 32 +/-7 cm/s, respectively; P<.0001). While the conventional indexes did not correlate with tau among the 36 patients in whom invasive studies were performed, FPV correlated well with tau (r = -0.76, P<.0001). Flow propagation velocity is a useful noninvasive index for the assessment of LV diastolic function in patients with HCM.     

心室功能评估中房室瓣环组织多普勒波形的测定

在诸多无创性评估心室功能的检测手段和方法中,多普勒组织成像(DTI)正得到临床的广泛应用,房室瓣环组织多普勒波形改变对心室功能的提示意义也逐渐受到重视.房室瓣环的运动代表了心肌纤维由基底部向心尖的运动,瓣环运动速度的测定可提供心室收缩期到舒张早期运动状态的信息.DTI获得的二尖瓣环收缩期运动速度波形可反映心梗缺血壁段引起的左室壁不协调性,并可用这些参数评价左室的整体收缩功能.三尖瓣环的DTI运动速度可以用于评价与下壁心梗相关的右室功能.因受前负荷变化的影响小,二尖瓣环DTI有助于鉴别二尖瓣的假阴性血流频谱,有助于无创性评估左室充盈压.一些影响房室瓣环DTI运动速度测定的因素目前难以消除,需结合其他多普勒参数和临床表现来分析.     

多普勒组织成像鉴别陈旧性心肌梗死患者舒张功能假性正常

目的 探讨应用多普勒组织成像（DTI）检测二尖瓣环舒张期运动速度可否鉴别陈旧性心肌梗死（OMI）患者舒张功能假性正常。 方法 OMI舒张功能假性正常患者68例，正常对照组50例，应用脉冲多普勒（PWD）分别测量二尖瓣口舒张早期峰值流速（E）、舒张晚期峰值流速（A）、E／A、E峰减速时间（DT）、左室等容舒张时间（IRT）、肺静脉收缩波（S）、舒张波（D）、S／D及心房收缩波（Ar）；转换DTI速度模式，测量左室侧壁缘二尖瓣环舒张早期运动峰值速度（Ea）、舒张晚期运动峰值速度（Aa）并计算Ea／Aa。 结果 OMI舒张功能假性正常患者与正常人的年龄和血流频谱E、A、E／A、IRT、D、S／D及二尖瓣环Aa测值比较无显著性差异（P〉0.05），DT缩短和S波降低具有显著性差异（P〈0．05），肺静脉血流Ar较正常人升高，而二尖瓣环Ea及Ea／Aa较比正常人明显减低，具有显著性差异（P〈0．01）。 结论 DTI检测二尖瓣环Ea及Ea／Aa比值可鉴别OMI患者舒张功能假性正常。     

Evaluation of left ventricular diastolic function by pulsed Doppler tissue imaging in mice.

BACKGROUND: Diastolic left ventricular (LV) function is commonly characterized by transmitral flow pattern in human beings. Recently, Doppler tissue imaging (DTI) was introduced to evaluate diastolic function. The aim of our study was to validate DTI in the evaluation of diastolic function in mice. METHODS: We measured indices of diastolic function using pulsed DTI, and transmitral Doppler and LV pressure and its maximal rate of decrease (LVdP/dt(min)), before and 4 weeks after aortic banding in C57BL/6 mice. RESULTS: Peak early diastolic velocity and ratio of peak early-to-late filling velocities, both measured by DTI, were significantly reduced after banding, thereby indicating diastolic dysfunction. Diastolic dysfunction was confirmed by impaired LV dP/dt(min), decreased transmitral early filling velocity, and transmitral early-to-late filling velocity ratio using transmitral Doppler. CONCLUSION: DTI detects diastolic dysfunction caused by chronic pressure overload in mice after aortic banding. DTI is suggested to be implemented as part of routine mouse echocardiography for evaluation of LV diastolic function.     

Differential effects of nebivolol and atenolol on transmitral diastolic filling parameters in patients with essential hypertension

INTRODUCTION: Impaired left ventricular (LV) diastolic relaxation, detected by pulsed Doppler echocardiography, is predictive of a higher incidence of major cardiovascular events in hypertensive patients. An improvement in LV diastolic function is an important goal of treatment. However, treatment of LV diastolic dysfunction remains empirical. The objective of our study was to compare the short-term effects of nebivolol and atenolol on Doppler diastolic filling parameters in hypertensive patients. METHODS: A total of 32 patients with mild-to-moderate hypertension were enrolled in the study. The patients were randomly assigned to receive treatment with either nebivolol (5 mg/day) or atenolol (50 mg/day) for 1 month. Diastolic filling parameters, with pulsed-wave Doppler transmitral flow velocities, were measured 1 day before and 1 month after treatment. RESULTS: Compared with baseline, both agents significantly decreased heart rate and blood pressure. However, there was no significant difference in pre-and post-treatment values between the nebivolol and atenolol groups. Both drugs significantly improved LV transmitral flow measured by early diastolic flow/atrial contraction signal (E/A) ratio, decreased deceleration time (DT) and isovolumetric contraction time (IVRT), but post-treatment improvement in E/A, DT and IVRT values was more significant with nebivolol compared with atenolol (P=0.05, P=0.05 and P=0.003, respectively). CONCLUSIONS: Although treatment with nebivolol or atenolol results in improved LV transmitral diastolic function filling parameters (E/A ratio, IVRT and DT), nebivolol has a greater effect compared with atenolol in patients with mild-to-moderate hypertension.     

Acute effects of smoking on diastolic function in healthy participants: Studies by conventional doppler echocardiography and doppler tissue imaging

The acute effects of smoking on left ventricular (LV) function were studied in 36 healthy participants (mean age 38 ± 10 years). The studies were made before and immediately and 30 minutes after smoking a cigarette. From apical 4- and 2-chamber views, the mitral annular velocities, determined by pulsed wave Doppler tissue imaging, were measured at 4 LV sites corresponding to the septum and the anterior, lateral, and inferior walls. A mean value from the 4 sites was used to assess LV function. The peak systolic, early diastolic, late diastolic, and the ratio of early to late diastolic velocities were recorded. In addition, other conventional Doppler echocardiographic diastolic parameters were also determined. Heart rate was increased immediately after smoking (from 67 ± 8 to 74 ± 10 bpm, P < .001). There was no change in systolic mitral annular velocity. Diastolic LV function was changed significantly immediately after smoking. The transmitral A wave increased (0.55 ± 0.1 vs 0.7 ± 0.1 m/s, P < .001), the transmitral E/A ratio decreased (1.5 ± 0.6 vs 1.1 ± 0.3, P < .001), and the transmitral E-wave deceleration time increased (186 ± 42 vs 211 ± 44 ms, P < .05). The diastolic myocardial velocity at the mitral annulus also changed significantly: the early diastolic velocity decreased (16 ± 3 vs 15 ± 3 cm/s, P < .001), the late diastolic velocity increased (10.9 ± 2.2 vs 12 ± 2.4 cm/s, P < .001), and the ratio of early to late diastolic annular velocities decreased (1.5 ± 0.5 vs 1.2 ± 0.4, P < .001). The changes in the transmitral flow velocities remained unaltered even 30 minutes afterward, although the heart rate returned to normal. The results were similar in both smokers and nonsmokers. Acute smoking of a cigarette influences LV diastolic function in healthy participants. The mechanism behind this effect cannot be explained only by changes in the heart rate or loading conditions. The mechanism is probably more complex. (J Am Soc Echocardiogr 2002;15:1232-7.)     

Tachycardia during the valsalva maneuver: a sign of normal diastolic filling pressures.

Alteration of the loading conditions during the Valsalva maneuver is a helpful ancillary method in the noninvasive assessment of diastolic filling of the heart by Doppler echocardiography. When tachycardia is induced by the maneuver, mitral inflow velocity curves may become uninterpretable because of E velocity (the initial early diastolic velocity on the transmitral flow velocity curve) and A velocity (the velocity at atrial contraction on the transmitral flow velocity curve) wave fusion. To determine the clinical significance of the E velocity and A velocity wave fusion, our study assessed the relation between the heart rate response induced by the Valsalva maneuver and the left ventricular filling pressures measured during cardiac catheterization. In all, 77 patients performed the maneuver during continuous hemodynamic and electrocardiographic monitoring. The ratio between the baseline R-R interval and the shortest R-R interval during the maneuver was calculated. A ratio value higher than 1.1 was predictive of a pre-A pressure of less than 18 mm Hg (94% positive predictive value). Reflex tachycardia during the Valsalva maneuver and subsequent fusion of the E velocity and A velocity waves on the mitral velocity curves is a sign of normal left ventricular filling pressures.     

多普勒组织成像评价高血压病患者左室舒张功能

目的　探讨应用多普勒组织成像 (DTI)技术检测二尖瓣环运动速度评估原发性高血压病左室舒张功能的应用价值。方法　应用DTI技术 ,对 5 6例原发性高血压病患者和 5 0例正常对照者二尖瓣环运动速度进行测定 ,并与常规多普勒超声心动图检查结果对照分析。结果　与正常组相比 ,高血压病患者收缩期DTI速度峰值 (S)差异无显著性意义 ,舒张早期DTI速度峰值 (Ve)显著减低 (P <0 .0 5 ) ,舒张晚期DTI速度峰值 (Va)无显著变化 ,舒张早期与舒张晚期DTI速度峰值的比值 (Ve Va)显著减低 (P <0 .0 5 )。Ve Va值与二尖瓣血流频谱E A值之间存在高度相关性。结论　DTI技术检测二尖瓣环舒张期运动速度参数可用于无创评价原发性高血压病左室舒张功能。