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1.
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.  相似文献   

2.
Respiratory variation of 25% or more in transmitral early diastolic filling (E) velocity is a well-recognized diagnostic feature of constrictive pericarditis (CP) that is useful for distinguishing it from restrictive cardiomyopathy. However, a subset of patients with CP do not exhibit the typical respiratory change. Recent data showed that mitral annular (E') velocity measured by Doppler tissue echocardiography (DTE) is markedly reduced in patients with restrictive cardiomyopathy whereas E' velocity is well-preserved in CP. This study evaluated the role of DTE for the diagnosis of CP when there is no characteristic respiratory variation of E velocity. From September 1999 to March 2001, 19 patients (17 men, 2 women; mean age, 57 +/- 13 years) with surgically confirmed CP underwent comprehensive echocardiography preoperatively, including pulsed wave and DTE examination with simultaneous recording of respiration. Nine (47%) of the 19 patients had less than 25% respiratory variation in E velocity. There was no significant difference in mitral inflow peak velocity, deceleration time, early-to-late ventricular filling ratio, and E' velocity between patients with and patients without respiratory variation of E velocity of 25% or more. Regardless of the presence or absence of a significant respiratory variation of E velocity, E' velocity was relatively normal (mean, 12 +/- 4 cm/s) in all patients with CP. In conclusion, E' velocity is well preserved in patients with isolated CP even when there is no characteristic respiratory variation of E velocity. Thus, when the respiratory variation in Doppler E velocity is blunted or absent during the evaluation of suspected CP in patients with restrictive mitral inflow velocity, preserved E' velocity shown by DTE should support the diagnosis of CP over a primary myocardial disease.  相似文献   

3.
Pulmonary venous flow as assessed by Doppler echocardiography is a current topic of investigation. Pulmonary venous flow has been used recently as part of a comprehensive assessment of left ventricular diastolic filling dynamics in restrictive myocardial diseases and constrictive pericarditis. Abnormalities of flow have been described in dilated cardiomyopathy, congenital heart disease, and arrhythmias. With the advent of transesophageal echocardiography, pulmonary venous flow can be readily obtained in all patients by pulsed-wave Doppler echocardiography. Recently, it has been used to assess the severity of mitral regurgitation and to estimate mean left atrial pressure. This article emphasizes the utility, physiology, and technique of measuring pulmonary venous flow with Doppler echocardiography in health and in disease.  相似文献   

4.
To evaluate the relation between left ventricular angiography and pulmonary venous flow velocity in native mitral valve regurgitation, 28 patients with sinus rhythm and valvular and/or coronary artery disease underwent transesophageal echocardiography within 24 hours after cardiac catheterization. Group I consisted of 17 patients, seven patients without (grade 0) and 10 patients with angiographically mild to moderate mitral regurgitation (grades 1 and 2). Group II consisted of 11 patients with angiographically severe mitral regurgitation (grades 3 and 4). Mitral regurgitation by transesophageal echocardiography was evaluated by measuring the regurgitant jet sizes and color-guided pulsed Doppler pulmonary venous flow velocities. Multivariate analysis revealed that the most powerful predictor (p less than 0.001) of angiographically severe (grades 3 and 4) mitral regurgitation was reversed systolic flow into the left upper pulmonary vein (sensitivity 82%, specificity 100%, positive predictive value 100%). If this variable was excluded from analysis, jet area and jet length (p less than 0.001) were the next best predictors for angiographically severe mitral regurgitation. Mean values of systolic peak pulmonary venous flow velocities were significantly lower in patients from group II, 13.0 +/- 11.1 cm/s versus 43.4 +/- 20.6 cm/s (group I) with p less than 0.005. This finding was also true for systolic time velocity integral, 1.3 +/- 1.3 cm (group II) versus 7.8 +/- 5.3 cm (group I) with p less than 0.005.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

5.
BACKGROUND: In most primary myocardial diseases, early diastolic mitral annulus velocity (E') decreases with disease progression. To our knowledge, constrictive pericarditis (CP) is the only condition without this phenomenon. OBJECTIVE: This study was performed to evaluate the diagnostic and pathophysiologic role of mitral annulus velocity in patients with CP. METHODS: In all, 17 patients with CP (9 men; mean age 46.5 +/- 14.3 years), 8 patients with cardiac tamponade (Tamp) (2 men; mean age 44.5 +/- 15.0 years), and age- and sex-matched control subjects for CP and Tamp were recruited for the study. Early mitral inflow velocity and E' were obtained while simultaneously recording respiration. In 8 patients with CP and in all patients with Tamp, these measurements were repeated after the relief of constrictive physiology or after pericardiocentesis. RESULTS: In patients with CP, E' was significantly higher than it was for control subjects (12.9 +/- 3.0 cm/s vs 9.8 +/- 2.4 cm/s, P <.01). An E' of 2 cm/s higher than the predicted normal E' could differentiate patients with CP from control subjects with a sensitivity of 76% and specificity of 82%. In 12 of 17 patients (71%), inspiratory E' was higher than expiratory E'-the opposite of mitral inflow variation. In 8 patients, E' decreased significantly after the relief of constrictive physiology (13.8 +/- 2.5 cm/s vs 9.3 +/- 3.1 cm/s, P <.05). In contrast, E' in the Tamp group was significantly lower than in the control group (6.8 +/- 1.6 cm/s vs 10.2 +/- 2.5 cm/s, P <.01), did not show significant respiratory variation, and increased significantly after pericardiocentesis (6.8 +/- 1.6 cm/s vs 9.5 +/- 3.0 cm/s, P <.05). CONCLUSION: E' is exaggerated in CP, which is helpful for diagnosis. The opposite phenomenon was noted in Tamp, a dissimilarity that might contribute to different hemodynamics.  相似文献   

6.
目的 应用组织多普勒技术定量评价缩窄性心包炎(CP)患者手术治疗后心脏收缩、舒张功能改变。 方法 选取已确诊为CP且择期接受CP心包剥脱术的患者22例,于手术前及术后1个月分别行超声检查,存储心尖四腔心、心尖两腔心及心尖部左心室长轴切面组织多普勒二维图像,以定量组织多普勒技术分析并记录二尖瓣环各部位及三尖瓣环侧壁收缩期及舒张期峰值运动速度(S'、E'),分别计算各个节段S'、E'及三尖瓣环的平均速度作为二尖瓣环的总体运动速度。 结果 CP患者术后1个月左心室变大(P<0.001),左心房(P=0.011)及右心房(P=0.004)呈不同程度缩小,左心室射血分数增高(P=0.021);三尖瓣环、二尖瓣环左心室侧壁及室间隔S'、E'均有不同程度减低(P均<0.05),三尖瓣环、二尖瓣环S'、E'峰亦有不同程度减低(P均<0.01)。 结论 CP患者术后左心室射血分数增加,心脏各腔室发生趋于正常的重构;术后短期内切除心包瓣环部位S'及E'较术前减低,表明左心室壁纵向运动速度减低。  相似文献   

7.
目的 评价彩色多普勒超声对缩窄性心包炎 (CP)与限制型心肌病 (RCM )的鉴别诊断价值。方法 应用彩色多普勒超声观察CP、RCM二尖瓣口、三尖瓣口、肺静脉及肝静脉血流状况 ,并用脉冲多普勒取样 ,记录其频谱随呼吸而发生的速率和时间变化 ,并与正常组进行对照。结果 在呼气与吸气时 ,CP组二尖瓣、三尖瓣舒张期速率峰值 (EM,ET)与正常组比较差异有显著性意义 (P <0 .0 5 ) ,且EM 随呼吸变化平均 >3 0 % ,而RCM和正常组平均 <5 % ;收缩期CP组二尖瓣、三尖瓣反流发生率明显低于RCM组 ,且程度较轻 ;CP组吸气与呼气时 ,分别发生肺静脉收缩期血流速率 (S)或舒张期血流速率 (D)值增大 ,而RCM组变化不明显 ;CP和RCM组肝静脉频谱D值和S值随呼吸呈不同的变化 ,而正常组受呼吸变化影响较小。结论 彩色多普勒血流显像技术为CP和RCM的鉴别提供了客观依据。如综合多项多普勒频谱征象并加以全面比较、分析 ,则具有相当的诊断和鉴别诊断价值及较高的敏感性和特异性  相似文献   

8.
Fifty-eight of 61 consecutive patients undergoing transesophageal echo-Doppler echocardiography provided excellent signals to permit assessment of pulmonary venous blood low patterns. Normal antegrade pulmonary venous flow during ventricular systole was biphasic and was characterized by a short, low velocity (28 +/- 17 cm/sec), early systolic jet (P1), and longer, higher velocity (41 +/- 23 cm/sec), late systolic jet (P2). Antegrade pulmonary venous flow during ventricular diastole (P3) was of moderate velocity (34 +/- 17 cm/sec) and was monophasic; during atrial contraction there was transient, low velocity (-17 +/- 11 cm/sec) and reversal of flow (P4). The early systolic antegrade venous flow (P1) was absent or reversed in rhythm disorders, which interrupted normal synchronized atrioventricular activation. These rhythm disorders also were associated with diminished peak flow velocities during late systole (P2). Abnormalities in systolic left ventricular function and mitral regurgitation also had this effect. Diastolic flow velocities (P3) remained constant, except in patients with mitral regurgitation. In these patients diastolic peak flows were significantly increased above normal. In cases of atrial fibrillation or ventricular pacing the late diastolic reversal of flow resulting from atrial contraction (P4) was absent. Conclusions: Transesophageal echo-Doppler echocardiography gives high quality signals of pulmonary venous inflow to help assess function of the left ventricle and left atrium. Multiple factors affect the patterns. This study suggests caution in the interpretation of abnormal patterns, particularly of reduced systolic pulmonary vein flow in the presence of left ventricular dysfunction, atrial fibrillation, ventricular pacing, and mitral regurgitation.  相似文献   

9.
Although cardiac dysfunction in hereditary hemochromatosis (HHC) can be evaluated by conventional echocardiography, findings are often not specific. To test the hypothesis that the assessment of (1) conventional Doppler left ventricular filling indexes and (2) intrinsic elastic properties of the myocardium by Doppler tissue echocardiography can both enhance the accuracy of echocardiographic diagnosis of cardiac involvement in HHC, a group of 18 patients with HHC (mean age 50 +/- 17 years) and 22 age-matched healthy subjects were studied. The following indexes were characteristic for HHC: (1) the duration of atrial reversal measured from pulmonary venous flow (ms) was longer (118 +/- 20 vs 90 +/- 16; P <.001); (2) systolic lateral mitral, early-diastolic medial mitral, and early-diastolic lateral tricuspid annular velocities were reduced by 23%, 31%, and 13%, respectively; (3) late-diastolic mean myocardial velocity and myocardial velocity gradient (MVG) were also reduced by 22% and 34%, respectively. Late-isovolumic relaxation (late-IVR) MVG (s(-1)) was positive in HHC as opposed to negative in healthy subjects (1.72 +/- 0.85 vs -0.89 +/- 1.15; P <.001) indicating impaired early-diastolic subepicardial relaxation in HHC. The assessment of atrial reversal flow duration, the difference in duration between A-wave and atrial reversal flow, and the presence of positive late IVR-MVG findings were the most accurate variables to differentiate patients with HHC from healthy subjects (80%, 67%, 94% sensitivity and 90%, 95%, 86% specificity, respectively).  相似文献   

10.
Previous studies that have validated Doppler indexes of mitral inflow have used pulsed wave sample volume locations either at the level of the mitral valve anulus or at the tips of the mitral valve leaflets. Although significant differences between absolute values for peak velocities and velocity time integrals at these sample volume locations have previously been reported, no information exists that has compared changes in inflow profiles after an intervention to improve left ventricular filling. To address this question, 13 patients with severe pulmonary hypertension (mean pulmonary artery pressure, 50 +/- 13 mm Hg) caused by chronic thromboembolic disease were studied with use of Doppler echocardiography immediately before and after surgical reduction of pulmonary hypertension (pulmonary vascular resistance decreased from 916 +/- 413 to 233 +/- 89 dynes.sec.cm5). This clinical model has been shown to have abnormal mitral inflow velocity profiles that improve markedly after surgery. Doppler measures of early and late peak velocities were significantly lower both before and after surgery when sampling at the mitral anulus compared with the leaflet tips, although late filling parameters and the deceleration of early flow velocity tended to differ little. With surgery, the significant increase in peak early velocity and the ratio of early to late velocity was present regardless of the sample volume location (peak E at leaflet tips, 47.1 +/- 16.0 to 68.9 +/- 15.4 [p less than 0.001], and at anulus, 40.7 +/- 11.3 to 56.2 +/- 14.6 cm/sec [p less than 0.001]; peak E/A at leaflet tips, 0.95 +/- 0.4 to 1.55 +/- 0.9, and at anulus, 0.78 +/- 0.3 to 1.32 +/- 0.7 [both p less than 0.02]).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

11.
The purpose of this study was to assess whether transthoracic Doppler echocardiography and serum natriuretic peptide levels could predict mean pulmonary capillary wedge pressure (PCWP) in patients with chronic atrial fibrillation. We examined mitral flow velocity and pulmonary venous flow (PVF) velocity patterns in 32 patients with chronic atrial fibrillation. Plasma A-type and B-type natriuretic peptide (ANP, BNP, respectively) levels in the peripheral vein were measured. Significant correlations were observed between mean PCWP and the following: peak velocity (r = 0.51) and deceleration time (r = -0.65) of the mitral flow; peak velocity (r = 0.64) and deceleration time (r = -0.80) of the PVF; BNP (r = 0.60); and ANP (r = 0.36). Stepwise multiple linear regression analysis selected PVF deceleration time and mitral flow deceleration time as independent predictors of PCWP. A cutoff value of PVF deceleration time of < or =150 ms and a mitral flow deceleration time of < or =100 ms predicted a mean PCWP of > or =18 mm Hg, with a sensitivity of 100% and 80% and a specificity of 96% and 85%, respectively. In conclusion, PVF deceleration time and mitral flow deceleration time obtained from transthoracic Doppler echocardiography are more accurate predictors of mean PCWP than values obtained with natriuretic peptides in patients with chronic atrial fibrillation.  相似文献   

12.
目的探讨超声心动图检测慢性阻塞性肺病(COPD)患者左心室功能和COPD病程的可行性。方法采用Sequoia512彩色超声诊断仪,记录21例COPD患者及50名健康人自然呼吸时二尖瓣口E峰、A峰血流速度,同步记录心电图和呼吸曲线,计算二尖瓣舒张早期E峰血流速度呼吸性波动指数(RVI)及E峰与A峰血流速度比值(E/A)呼吸变化率。结果两组均表现为E峰血流速度、E/A吸气相低于呼气相(P〈0.001);COPD组A峰血流速度吸气相与呼气相差异无统计学意义(P=0.076),而健康对照组A峰血流速度吸气相低于呼气相(P〈0.001)。COPD组二尖瓣E峰血流速度RVI及E/A呼吸变化率均较对照组增大(P=0.002)。结论自然呼吸对COPD患者二尖瓣血流影响具有规律性,进一步验证了呼吸影响心功能机制新假说,同时也为利用多普勒技术评价COPD患者左室功能损害程度和肺实质病变严重程度的进一步研究提供更多信息。  相似文献   

13.
缩窄性心包炎肝静脉血流多普勒频谱变化特征   总被引:1,自引:0,他引:1  
目的探讨缩窄性心包炎肝静脉血流多普勒频谱变化特征.方法应用彩色多普勒超声心动图检测了30例缩窄性心包炎患者肝静脉血流多普勒频谱变化,并与31例正常人及20例肺动脉高压者对比观察.结果缩窄性心包炎组肝静脉血流多普勒频谱 s波较正常组及肺动脉高压组明显降低;d波与正常组无明显差异,但较肺动脉高压组明显增高;s/d比值较两组显著减低,若以该比值<1作为判断缩窄性心包炎的标准,敏感性为78%,特异性达95%.结论肝静脉血流多普勒频谱变化可作为评价缩窄性心包炎的一种方法.  相似文献   

14.
AIM: To specify effectiveness of different methods for assessment of diastolic function in patients with pre-dialysis chronic renal failure (CRF). MATERIAL AND METHODS: Forty non-diabetic pre-dialysis CRF patients (20 males and 20 females, mean age 51 +/- 11 years) were studied. Serum creatinine was 209.3 +/- 117.4 mcmol/l. 19 patients had chronic heart failure (CHF) of NYHA class I-III. M-mode echocardiography and Doppler echocardiography were performed. Transmitral and pulmonary venous flows were assessed by Doppler echocardiography and the flow propagation velocity (Vp) was estimated by color M-mode Doppler echocardiography. The ratio of peak E-wave velocity of transmitral flow to Vp (E/Vp) was calculated. All the patients had preserved systolic function (ejection fraction > 45%). RESULTS: Interpretation of transmitral flow was difficult in 16 (40.0%) patients. During Valsalva's manoeuvre the E-wave peak velocities, the A-wave velocities and the ratio E/A were decreasing. However, we did not reveal any correlation between E/A and NYHA class of heart failure (r = 0.18; p = 0.32). Interpretation of pulmonary venous flow was possible only in 24 (60.0%) patients. Vp estimation by color M-mode Doppler echocardiography improved evaluation of diastolic function in 15 of 16 patients with problems of transmitral flow assessment. A negative correlation was revealed between NYHA class and Vp (r = -0.39; p = 0.013) and a positive correlation was between NYHA class and E/Vp (r = 0.45; p = 0.004). CONCLUSION: Vp assessed by color M-mode Doppler echocardiography improves the diagnosis of diastolic dysfunction in patients with chronic renal insufficiency. This method has an advantage over pulmonary venous flow investigation. The Valsalva's manoeuvre is low-effective for differential diagnosis of transmitral flow types.  相似文献   

15.
In certain patients, pulmonary venous flow pattern obtained by the pulsed wave Doppler during transesophageal echocardiography shows a notching on the atrial reversal (A) wave. However, the incidence or the mechanism of this notched A wave has not been described. After transthoracic echocardiographic evaluation for the chamber sizes, wall thickness, and left-ventricular function, transesophageal echocardiography was performed in 100 patients with in sinus rhythm. Discernible pulmonary venous A wave was observed in 46 patients. Among these 46 patients, notched A wave was observed in 11 (31%). In 4 patients with notched A wave, left-atrial pressure waveforms could be obtained during mitral balloon valvuloplasty. In all these patients, left-atrial pressure waveforms showed prominent c waves. In 2 patients, transesophageal echocardiography was repeated after mitral balloon valvuloplasty. Late peak of the notched A wave decreased with the decrease in the magnitude of rise in left-atrial c wave. Among the transthoracic echocardiographic parameters, patients with notching (n = 11) had significantly larger left atriums than patients without notching (n = 35)(49.3 +/- 6.2 vs 37.3 +/- 4.4 mm, P <.0001). There were no significant differences in left-ventricular dimensions, wall thickness, and ejection fraction. In conclusion, notched pulmonary venous A wave indicates the presence of left-atrial c wave; and presence of left-atrial c wave may represent decreased left-atrial compliance.  相似文献   

16.
本文应用双平面经食管多普勒测定了20例正常人和38例二尖瓣返流(MR)患者的肺静脉血流频谱,旨在评价不同程度MR对肺静脉(PV)回流的影响。结果表明:①与正常组相比,明显MR组PV收缩期峰值流速及流速积分显著降低(P<0.02),而舒张期峰值流速及流速积分显著升高(P<0.05及0.02),且随着MR程度的加重,上述改变更趋明显;②38例MR患者中,24例记录到PV收缩期负向波,其中轻度MR4例(33.3%),中度MR7例(70%),重度MR13例(81.2%),房颤及窦性心律的MR患者出现PV负向波的例数无明显差异(12/19对10/19,P=0.37);③MR时,PV收缩期负向波流速与MR返流束面积和长度正相关(r分别为0.51及0.41,P=0.001和0.014),而与MR最大返流速度及返流压差不相关(P>0.05)。结论:MR对肺静脉血流具有重要影响,主要是使肺静脉在收缩期的回流减慢甚至出现倒流,后者尤常见于重度MR者,因此测定肺静脉血流频谱有助于对MR严重性的估价  相似文献   

17.
Left ventricular(LV) diastolic dysfunction with preserved LV systolic function is common among patients with hypertension, especially with LV hypertrophy. Doppler echocardiography is one of the most useful clinical tools for the evaluation of diastolic function. Mitral inflow and pulmonary venous flow velocities are used not only for the assessment of diastolic function but also for predicting prognosis. Recently, tissue Doppler echocardiography has been also applied to evaluate diastolic function. Accurate assessment of diastolic function has been demonstrated by measuring both mitral annulus and mitral inflow velocity. In this article, We review the diagnosis of diastolic dysfunction by Doppler echocardiography using mitral inflow velocity, pulmonary venous flow velocity and mitral annulus velocity measured by tissue Doppler imaging.  相似文献   

18.
肺静脉血流频谱评价冠心病患者左心室舒张功能的价值   总被引:5,自引:0,他引:5  
目的:应用彩色多普勒超声心动图研究冠心病患者肺静脉血流频谱对左心室舒张功能的价值。方法:用彩色多普勒超声心动图检测冠心病患者和相同年龄组正常人各45例的右上肺静脉血流频谱峰值(Sp、Dp、ap)及其速度时间积分(Si、Di、ai),与所检测的二尖瓣口血流频谱峰值(Ep、Ap)、速度时间积分(Ei、Ai)及等容舒张时间相比较,将结果对比分析。结果:冠心病组ap、ai较正常组显著增大,Si、Dp、Di和Dp/ap、Di/ai值明显减小,ap、ai增大幅度与左室舒张功能明显相关。二尖瓣口血流频谱测值一般反映了左室舒张功能状态,但对几例出现的“伪正常”频谱表现难以明确评价。结论:肺静脉血流可直观反映冠心病患者左心房内的压力状态,其频谱特征与二尖瓣口血流频谱结合评价左室舒张功能较用二尖瓣口血流频谱一种方法更加准确可靠。  相似文献   

19.
BACKGROUND: Cardioversion by direct current (DC) and other methods can cause atrial "stunning." There are case reports of acute pulmonary edema after DC cardioversion, but whether acute ventricular dysfunction is a general consequence of DC cardioversion is unknown. We have investigated whether DC cardioversion acutely affects myocardial velocity assessed by Doppler tissue imaging. METHODS: 40 patients (30 with atrial fibrillation and 10 with atrial flutter) undergoing elective DC cardioversion underwent transthoracic echocardiography with Doppler tissue imaging before and immediately after cardioversion, and after follow-up. Peak systolic velocity was derived for 6 ventricular segments using Doppler tissue imaging. RESULTS: Immediately after DC cardioversion of atrial fibrillation, peak systolic velocity decreased in basal lateral (4.3 +/- 2.0-3.3 +/- 1.7 cm/s, P <.001), mitral annulus-septal (3.8 +/- 1.0-3.5 +/- 0.9, P <.05), mitral annulus-lateral (4.9 +/- 1.6-4.1 +/- 1.7, P <.001), and tricuspid annular (7.8 +/- 2.0-7.0 +/- 1.2, P <.03) segments, even though left ventricular ejection fraction was unchanged. In contrast, for the atrial flutter group there were no significant changes in peak systolic velocity in any segment post-DC cardioversion. Follow up studies were performed after sustained in sinus rhythm in both atrial fibrillation and atrial flutter groups. For both groups, increased peak systolic velocity was found in all 6 segments on follow-up (all P <.05). CONCLUSIONS: DC cardioversion causes subclinical, acute reversible reduction in left ventricular peak systolic velocity in patients with atrial fibrillation. The causes of this reduction in myocardial contractile velocity and the circumstances in which acute dysfunction become clinically significant warrant further investigation.  相似文献   

20.
目的探讨二尖瓣狭窄(二狭)患者下腔静脉回流入右房状态。方法用彩色多普勒超声心动图对74例二狭患者及32例对照者沿胸骨右缘纵切探查下腔静脉口的最大内径及血流速度。结果对照组、二狭并轻度三尖瓣返流者(Ⅰ组)、二狭并中度三尖瓣返流者(Ⅱ组)及二狭并重度三尖瓣返流者(Ⅲ组)四组的下腔静脉口内径有显著差异(分别为20.1±2.4mm、17.0±5.9mm、16.1±6.2mm及27.8±10.2mm)。但四组的下腔静脉口峰值血流速度及平均血流速度无明显的差别。简单线性相关分析发现二狭非重度三尖瓣返流者(Ⅰ组、Ⅱ组)的下腔静脉口内径与其峰值血流速度之间呈明显的负相关关系(r=-0.62,P<0.01),且下腔静脉口内径与左房内径亦呈明显负相关关系(r=-0.71,P<0.01)。结论二狭患者增大的左房可引起下腔静脉口的静脉回流减少  相似文献   

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