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1.
The present study evaluated the prevalence of mechanical inter- and intraventricular dyssynchrony in patients with heart failure and preserved left ventricular (LV) ejection fraction (LVEF). We studied 138 patients with heart failure (age 67+/-11 years; 76% men); 60 patients had preserved LVEF (>40%). Using conventional Doppler echocardiography, an interventricular mechanical delay>or=40 ms was defined as interventricular dyssynchrony. Using pulse-wave tissue Doppler imaging, the time from the beginning of the QRS complex to onset of systolic motion was measured in 4 basal LV segments. A dispersion of >or=60 ms was defined as intraventricular dyssynchrony. The prevalence of inter- and intraventricular dyssynchrony was lower in patients with preserved LVEF than in those with reduced LVEF (17% vs 41%, p<0.01 for interventricular dyssynchrony, 18% vs 36%, p<0.01 for intraventricular dyssynchrony). However, patients with preserved LVEF and a QRS width>or=120 ms had higher values for the parameters for inter- and intraventricular dyssynchrony than patients with a QRS width<120 ms (interventricular mechanical delay 33+/-20 vs 20+/-16 ms, p<0.05; tissue Doppler imaging dispersion 42+/-26 vs 33+/-22 ms, p<0.05). In patients with a QRS width>or=120 ms, the prevalence of inter- and intraventricular dyssynchrony was comparable for patients with preserved and reduced LVEF (42% vs 55%, p=NS for interventricular dyssynchrony and 45% vs 46%, p=NS for intraventricular dyssynchrony). In conclusion, the prevalence of inter- and intraventricular dyssynchrony was low (17% and 18%, respectively) in patients with heart failure and preserved LVEF. However, in the presence of a QRS width of >or=120 ms, this prevalence increased to almost 50%, comparable to that for patients with heart failure and reduced LVEF and a QRS width of >or=120 ms.  相似文献   

2.
OBJECTIVES: The purpose of this study was to determine the prevalence of systolic and diastolic dyssynchrony in diastolic heart failure (DHF) patients and identify the effects of medical therapy. BACKGROUND: The prevalence of systolic and diastolic dyssynchrony in DHF patients is unknown with no data on the effects of medical therapy on dyssynchrony. METHODS: Patients presenting with DHF (n = 60; 61 +/- 9 years old, 35 women) underwent echocardiographic imaging simultaneous with invasive measurements. An age-matched control group of 35 subjects and 60 patients with systolic heart failure (SHF) were included for comparison. Systolic and diastolic dyssynchrony were assessed by tissue Doppler and defined using mean and SD values in the control group. RESULTS: Systolic dyssynchrony was present in 20 patients (33%) with DHF and 24 patients (40%) with SHF and was associated in both groups with significantly worse left ventricular (LV) systolic and diastolic properties (p < 0.05 vs. control group and patients without systolic dyssynchrony). Diastolic dyssynchrony was present in 35 patients (58%) with DHF and 36 patients (60%) with SHF and had significant inverse correlations with mean wedge pressure and time constant of LV relaxation. In DHF patients, medical therapy resulted in significant shortening of diastolic time delay (39 +/- 23 ms to 28 +/- 20 ms; p = 0.02) but no significant change in systolic interval (p = 0.15). Shortening of diastolic time delay correlated well with tau shortening after therapy (r = 0.85; p < 0.001). CONCLUSIONS: Systolic dyssynchrony occurs in 33% of DHF patients, and diastolic dyssynchrony occurs in 58%. Medical therapy results in significant shortening of the diastolic intraventricular time delay which is closely related to improvement in LV relaxation.  相似文献   

3.
BACKGROUND: Echocardiographic examination is essential for clinical assessment of patients after cardiac resynchronisation therapy (CRT). AIM: To assess the benefit of CRT in patients with end-stage heart failure at long-term follow-up. METHODS: 28 patients with end-stage heart failure, NYHA class >or= III (>or= II in patients with indications for implantable cardioverter defibrillator and echocardiographic signs of ventricular mechanical systolic dyssynchrony), left ventricular ejection fraction (LVEF) <35%, QRS duration >120 ms and left bundle branch block morphology received a biventricular device. Standard colour Doppler echocardiography examination was performed at baseline, and then every 6 months, up to 2 years. Parameters of systolic and diastolic LV function, mitral insufficiency and right ventricular (RV) pressure were evaluated. RESULTS: Following CRT, a statistically significant improvement of LV dimensions (p<0.05), and LVEF (p<0.001) was recorded. CRT also resulted in a mitral regurgitation decrement (p<0.01). Interventricular mechanical delay was shortened (p=0.0005). After 2 years, non-significant worsening of LV dimensions was observed. At long-term follow-up CRT did not result in LV volume, left atrium, RV dimension or RV pressure reduction. CONCLUSIONS:CRT is associated with reverse remodelling of the LV at mid-term follow-up.  相似文献   

4.
AIMS: Information on the prevalence and clinical, electrocardiographic and echocardiographic inter-relationships of mechanical dyssynchrony among patients with heart failure (HF) and left ventricular systolic dysfunction derives mainly from relatively small studies. The CARE-HF trial provides the opportunity to address these issues in a large population of patients with advanced HF. METHODS AND RESULTS: The CARE-HF trial enrolled patients with New York Heart Association (NYHA) class III or IV HF, with a QRS duration > or =120 ms, left ventricular (LV) ejection fraction (EF) < or =35% and LV end diastolic diameter > or =30 mm/m (height in m). Patients underwent a thorough echocardiographic evaluation, which included assessment of LV structure, systolic function, mitral inflow pattern, right ventricular (RV) dimensions and function, and interventricular mechanical delay (IVMD) as an index of interventricular dyssynchrony. Echocardiographic measurements were made in a Core Laboratory to ensure consistent quantitative analysis. Of the 813 patients enrolled, 735 had a baseline echocardiographic examination suitable for measurement. Overall patients had advanced LV dysfunction (mean EF 25.5%) but few had a restrictive mitral filling pattern (18%) and both the mean RV diameter and RV function were within normal limits. Interventricular dyssynchrony defined as IVMD >40 ms was present in 455 patients (62%). Clinical, electrocardiographic and standard echocardiographic variables were only loosely associated with IVMD. CONCLUSIONS: Interventricular dyssynchrony appears to be an independent characteristic of patients with advanced HF, and is poorly related to clinical, electrocardiographic or standard echocardiographic variable.  相似文献   

5.
BACKGROUND: The clinical response to biventricular pacing is unpredictable, especially in patients with ischemic cardiomyopathy. OBJECTIVES: The purpose of this study was to prospectively examine the relationship between the extent of myocardial viability and the response to cardiac resynchronization therapy. METHODS: Twenty-one patients with ischemic left ventricular (LV) dysfunction (left ventricular ejection fraction [LVEF] 21 +/- 5%), New York Heart Association (NYHA) functional class III-IV, and QRS >120 ms received biventricular devices. Myocardial viability was assessed by myocardial contrast echocardiography, and a perfusion score index (PSI) was calculated from summed segmental perfusion scores. LV performance was assessed by echocardiography on the day after implantation and at 6 months. RESULTS: PSI was closely correlated with acute improvement in LVEF (P = .003, r = 0.65), stroke volume (P = .02, r = 0.54), and end-systolic volume (P = .05, r = -0.49). PSI also correlated with early diastolic LV relaxation (E', P < .05, r = 0.50) and global myocardial performance or Tei index (P = .003, r = 0.63). By multiple linear regression analysis, PSI provided incremental predictive value to the degree of dyssynchrony, measured by tissue Doppler imaging, for predicting improvement in LVEF. At 6 months, PSI remained positively correlated with improvement in ventricular performance and with reduction in LV end-diastolic dimension (P = .003, r = -0.68). PSI also influenced the clinical variables of NYHA class, 6-minute walk distance, quality-of-life score, and number of hospitalizations for heart failure. CONCLUSION: In patients with ischemic cardiomyopathy, the extent of myocardial viability predicts acute and long-term improvement in LV performance, exercise tolerance, and reduction in LV end-diastolic dimension with biventricular pacing.  相似文献   

6.
目的评价心电图QRS间期与慢性心力衰竭(心衰)左心室同步性的关系。方法对54例慢性心衰患者(宽QRS组28例,正常QRS组26例)和15例健康人(对照组)进行心肌组织多普勒成像研究,测量收缩期和舒张早期12节段达峰时间(Ts和Te),评价不同QRS间期的慢性心衰左心室各节段不同步状况以及左心室不同步的主要影响因素。结果慢性心衰舒张末期和收缩末期容积增大,宽QRS组较正常QRS组更加显著,12节段平均Ts显著增大。以Ts≥182ms作为分界值,正常QRS组46%、宽QRS组71%存在收缩期不同步。宽QRS组Te最大差值(Te-diff)最大,以Te-diff≥79ms作为分界值,正常QRS组58%、宽QRS组89%存在舒张期不同步。同时存在收缩期和舒张期不同步者,正常QRS组为31%,宽QRS组为64%。收缩末期容积与左心室收缩期不同步相关,舒张末期容积与舒张期不同步相关。结论心电图QRS间期不能完全反映慢性心衰左心室同步性状况,左心室收缩末期容积和舒张末期容积直接影响左心室的收缩期和舒张期同步性。  相似文献   

7.
Cardiac resynchronization therapy (CRT) is beneficial in selected patients with moderate to severe heart failure (New York Heart Association [NYHA] classes III to IV). Patients with mildly symptomatic heart failure (NYHA class II) are currently not eligible for CRT and the potential beneficial effects in these patients have not been well studied. Fifty consecutive patients in NYHA class II heart failure and 50 consecutive patients in NYHA classes III to IV (control group) were prospectively included. All patients had left ventricular (LV) ejection fraction120 ms. The effects of CRT in NYHA class II patients were compared with the results obtained in both groups. The severity of baseline LV dyssynchrony (assessed with color-coded tissue Doppler imaging) was comparable between patients in NYHA class II versus those in NYHA classes III to IV (83+/-49 vs 96+/-51 ms, p=NS); resynchronization was achieved in all patients. NYHA class II patients showed a significant improvement in LV ejection fraction (from 25+/-7% to 33+/-10%, p<0.001) and reduction in LV end-systolic volume (from 168+/-55 to 132+/-51 ml, p<0.001) after CRT, similar to patients in NYHA classes III to IV. In addition, only 8% of NYHA class II patients had progression of heart failure symptoms. In conclusion, CRT had comparable effects in patients in NYHA class II and in NYHA classes III to IV heart failure in terms of LV resynchronization, improvement in LV ejection fraction, and LV reverse remodeling.  相似文献   

8.
Cardiac resynchronization therapy in patients with a narrow QRS complex.   总被引:8,自引:0,他引:8  
OBJECTIVES: The purpose of this study was to evaluate the effects of cardiac resynchronization therapy (CRT) in heart failure patients with narrow QRS complex (<120 ms) and evidence of left ventricular (LV) dyssynchrony on tissue Doppler imaging (TDI). BACKGROUND: Cardiac resynchronization therapy is beneficial in selected heart failure patients with wide QRS complex (> or =120 ms). Patients with narrow QRS complex are currently not eligible for CRT, and the potential effects of CRT are not well studied. METHODS: Thirty-three consecutive patients with narrow QRS complex and 33 consecutive patients with wide QRS complex (control group) were prospectively included. All patients needed to have LV dyssynchrony > or =65 ms on TDI, New York Heart Association (NYHA) functional class III/IV heart failure, and LV ejection fraction < or =35%. RESULTS: Baseline characteristics, particularly LV dyssynchrony, were comparable between patients with narrow and wide QRS complex (110 +/- 8 ms vs. 175 +/- 22 ms; p = NS). No significant relationship was observed between baseline QRS duration and LV dyssynchrony (r = 0.21; p = NS). The improvement in clinical symptoms and LV reverse remodeling was comparable between patients with narrow and wide QRS complex (mean NYHA functional class reduction 0.9 +/- 0.6 vs. 1.1 +/- 0.6 [p = NS] and mean LV end-systolic volume reduction 39 +/- 34 ml vs. 44 +/- 46 ml [p = NS]). CONCLUSIONS: Cardiac resynchronization therapy appears to be beneficial in patients with narrow QRS complex and severe LV dyssynchrony on TDI, with similar improvement in symptoms and comparable LV reverse remodeling to patients with wide QRS complex. The current results need confirmation in larger patient cohorts.  相似文献   

9.
目的 观察心脏再同步化治疗对窄QRS波群慢性心力衰竭患者的临床疗效. 方法 对5例QRS时间<120ms的慢性心力衰竭患者行双心室再同步起搏治疗.术后随访(15.6±12.1)个月,观察心功能、活动耐量、夜间心率、心率变异性(SDNN)和左心室射血分数;组织多普勒检测左心室内各心室壁收缩期达峰时间标准差(Ts-SD);三维超声心动描记术检测左心室16、12、6节段达最小容积点时间的标准差(Tmsv-Dis)和最大时间差(Tmsv-Dif). 结果 治疗后心功能NYHA分级从Ⅲ、Ⅳ级改善为Ⅱ、Ⅲ级,活动度从(0.03±0.05)h/d增加至(2.93±1.10)h/d,夜间心率由(85.0±3.6)次/min降低至(62.3±2.5)次/min,SDNN从(48.3±7.6)ms升至(116.7±5.8)ms,左心室射血分数从(21.2±4.5)%提高至(34.7±5.1)%(P<0.05). Ts-SD,Tmsv-Dis及Tmsv-Dif均有明显减低(P<0.05). 结论 窄QRS波群慢性心力衰竭患者可接受心脏再同步化治疗,术前应用超声心动描记术及组织多普勒等评价患者心室运动的失同步是很必要的.  相似文献   

10.
There is a wide variation (13% to 74%) in the reported prevalence of heart failure associated with normal left ventricular (LV) systolic function (diastolic heart failure). There is no published information on this condition in China. To ascertain the prevalence of diastolic heart failure in this community, 200 consecutive patients with the typical features of congestive heart failure were studied with standard 2-dimensional Doppler echocardiography. A LV ejection fraction (LVEF) >45% was considered normal. The results showed that 12.5% had significant valvular heart disease. Of the remaining 175 patients, 132 had a LVEF >45% (75%). Therefore, 66% of patients with a clinical diagnosis of heart failure had a normal LVEF. Heart failure with normal LV systolic function was more common than systolic heart failure in those >70 years old (65% vs 47%; p = 0.015). Most (57%) had an abnormal relaxation pattern in diastole and 14% had a restrictive filling pattern. In the systolic heart failure group, a restrictive filling pattern was more common (46%). There were no significant differences in the sex distribution, etiology, or prevalence of LV hypertrophy between these 2 heart failure groups. In conclusion, heart failure with a normal LVEF or diastolic heart failure is more common than systolic heart failure in Chinese patients with the symptoms of heart failure. This may be related to older age at presentation and the high prevalence of hypertension in this community.  相似文献   

11.
Left ventricular (LV) systolic dyssynchrony is an important pathologic mechanism in patients with heart failure (HF). However, the prevalence of intraventricular dyssynchrony in patients with different LV ejection fractions (EFs) is unknown. This study evaluated 402 consecutive patients with HF (mean age 64.99 +/- 13.15 years, 72.4% men) and 120 healthy controls. Dyssynchrony indexes included the SD of the time to peak systolic velocity (Ts) in ejection phase in the 12-segmental model (Ts-SD) and the difference in Ts between basal septal and basal lateral segments (Ts-Septal-Lateral) using tissue Doppler imaging. Patients were divided into 3 groups according to LVEF (LVEF <20%, >20% to 35%, and >35% to 50%) and compared with healthy controls. Both indexes were significantly higher in all 3 LVEF groups compared with controls (p <0.0001). Based on the established cut-off values, systolic dyssynchrony was equally prevalent in all 3 LVEF groups and was 67%, 62%, and 55% using Ts-SD and 38%, 36%, and 35% using Ts-Septal-Lateral, respectively. However, the prevalence of systolic dyssynchrony was higher using Ts-SD than Ts-Septal-Lateral (chi-square = 94.43, p <0.001). Conversely, the prevalence of electrical dyssynchrony, defined as a >120-ms QRS duration, decreased significantly with increasing LVEF (44%, 35%, and 16%; chi-square 5.60, p <0.001). In conclusion, the prevalence of mechanical systolic dyssynchrony was independent of severity of LV systolic dysfunction. This may implicate the potential role of cardiac resynchronization therapy for those with LVEF of 35% to 50%, in particular when systolic dyssynchrony is present.  相似文献   

12.
Tissue Doppler imaging-derived intra-left ventricular (LV) contractile dyssynchrony is an evolving prognostic parameter for patients with systolic heart failure (HF). However, whether and how exercise could abolish the synchronicity in HF patients with narrow QRS remains less studied. We evaluated a total of 33 HF patients with impaired LV ejection fraction (<50%), QRS duration < or =120 ms, and baseline dyssynchrony index (DI; standard deviation of electromechanical delay of 12 LV segments by tissue Doppler imaging) <33 ms. After a 6-minute treadmill exercise by modified Bruce protocol, the absolute time difference from QRS onset to peak systolic myocardial velocity of each segment was recorded immediately. With similar DI at rest and peak heart rates during exercise, 11 patients (33%) developed dyssynchrony (DI > or =33 ms) after exercise, and the others did not (44.7 +/- 8.0 vs 16.2 +/- 8.3 ms, p <0.001). Patients with dyssynchrony after exercise had greater baseline mitral early diastolic velocity/annular early diastolic velocity (E/Ea) (19 +/- 17 vs 10 +/- 5, p <0.026). Multivariate analysis revealed mitral E/Ea >10 at rest, indicating higher LV filling pressure, independently predicted the exercise-evoked dyssynchrony (odds ratio 18, 95% confidence interval 2 to 163, p <0.012). In conclusion, exercise uncovered masked LV dyssynchrony in 1/3 of systolic HF patients with narrow QRS, and exercise-provoked dyssynchrony could be predicted by mitral E/Ea >10 at rest.  相似文献   

13.
BACKGROUND: Cardiac resynchronization therapy (CRT) provides benefit for congestive heart failure (CHF), but predictors of the clinical response are debated. OBJECTIVE: The aim of this prospective study was to assess the predictive role of dobutamine stress echocardiography (DSE) in identifying a suitable candidate for CRT. METHODS: From March 2001 to December 2003, 71 CHF patients were prospectively enrolled on the basis of four criteria: New York Heart Association (NYHA) class III and IV; QRS > or =150 ms with a left bundle branch block pattern, and left ventricular ejection fraction (LVEF) < or =35% under optimal medical treatment. The combined endpoints were hospital readmission for class IV CHF, heart transplant (HT), and CHF-related death. RESULTS: The 67 patients completing the study presented with the following characteristics: age (70 +/- 10 years; 11 women); etiology (idiopathic in 44, ischemic in 23); NYHA class (40 in class III and 27 in class IV); LVEF 26% (+/-5%); QRS duration (190 +/- 28 ms); 6-minute walk test 330 m (+/-108); peak oxygen uptake 10.7 (+/-3.3 mL/kg/min); mitral insufficiency in 42 (> or =III grade); interventricular (IV) delay (62 +/- 21 ms); and intraventricular dyssynchrony in 30 patients. Over the follow-up period of 12.1 +/- 8.7 months, 20 (29.9%) of 67 patients presented with at least one hemodynamic event: hospitalization for CHF in 19 (28%) of 67, HT in 2 (3%) of 67, and CHF death in 7 (10%) 67. Univariate analysis identified NYHA class (P = .03), LVEF (P = .015), IV dyssynchrony before (P = .038) and after CRT (P = .0035), IV delay after CRT (P = .002), 6-minute walk distance (P = .01), and DSE Res+ (P = .008) as significant predictors of clinical events. A receiver operating curve established a cut-off value of 1.25 for the DSE responders (Res+: 34 patients at 10 microg/kg/min infusion rates), and the improvement at the 10 microg/kg/min level was 41% +/- 7% in Res+ and 29% +/- 8% in nonresponders (P<.0001). With a cut-off value of 1.25-fold the LVEF increase, the DSE test exhibits 70% sensitivity, 61.7% specificity, 43.8% positive predictive value, and 82.9% negative predictive value. Cox analysis identified IV dyssynchrony before CRT (P = .01) and DSE Res+ (P = .003) as independent predictive factors. CONCLUSIONS: Independent predictive factors of severe hemodynamic clinical outcome in patients with CRT are IV dyssynchrony and DSE.  相似文献   

14.
目的探讨老年心力衰竭患者血浆氨基末端脑利钠肽前体(NT-proBNP)、左心室射血分数(LVEF)与纽约心功能分级(NYHA)的关系。方法入选2006年1月至2011年10月在我院住院的年龄≥60岁NYHAⅡ~Ⅳ级的慢性心力衰竭患者308例,分为收缩性心力衰竭(SHF)(LVEF<50%)组210例、射血分数正常的心力衰竭(HFNEF)(LVEF>50%)组98例,同期非心力衰竭住院无器质性心脏病患者150例作为对照组,采用电化学发光免疫法检测血浆NT-proBNP浓度,心脏彩色多普勒超声测定左心室结构和LVEF、左心室舒张功能(Ea/Aa)。结果血浆NT-proBNP水平随NYHA分级的增加而升高,二者呈正相关(r=0.862,P<0.01);LVEF与NYHA分级呈负相关(r=-0.614,P<0.05);血浆NT-ProBNP水平与LVEF无明显相关性(r=-0.136,P=0.09)。在SHF组NT-proBNP水平与LVEF呈负相关(r=-0.735,P=0.008),在HFNEF组NT-proBNP水平与Ea/Aa呈正相关(r=0.614,P=0.009)。结论血浆NT-proBNP水平能较好地反映老年慢性心力衰竭患者的心功能状态,LVEF与NT-proBNP结合应用不仅能更好地反映患者心功能状态,同时有助于HFNEF的诊断。  相似文献   

15.
We evaluated the role of clinical, BNP and echocardiographic left ventricular (LV) indices in predicting the development of acute heart failure (HF) following beta-blocker initiation and uptitration in 50 stable CHF patients with LVEF < 40% and creatininemia < 250 micromol/l. Use of NYHA class alone predicted the development of acute HF decompensation in only 56% and the absence of this event in 93% of patients. Use of echocardiographic indices (systolic PAP < 40 mmHg or E/A ratio < 1.4 or EDT > 145 ms) predicted the absence of acute HF decompensation in 100% of patients. Use of NYHA > 3 combined with BNP > 398 pg/ml or with echocardiographic indices (i.e. systolic PAP > 40 mmHg or E/A > 1.4 or EDT < 145 ms) predicted the development of acute HF decompensation in 100% of patients. In conclusion use of BNP and echocardiographic LV filling pressure indices in combination with NYHA class may predict beta-blocker tolerance more accurately than clinical indices alone in patients with LV systolic dysfunction (LVEF < 40%).  相似文献   

16.
BACKGROUND: Cardiac resynchronization therapy (CRT) is recommended for patients with NYHA class III-IV refractory heart failure (HF), ejection fraction <35% and a QRS >120 ms. We attempted to identify responders to CRT from echocardiographic (echo) indices of mechanical dyssynchrony in patients with QRS<150 ms. METHODS AND RESULTS: The study enrolled 51 men and 9 women (mean age: 64.5 years) in NYHA class III (n=54) or IV (n=6) presenting with a mean ejection fraction: 25.7%, LV end-diastolic diameter: 69.1 mm, and QRS=121+/-19 ms. All patients were implanted with a CRT system and followed for 1 year. Implantation was preceded and followed by clinical, functional and Doppler (D)-echo evaluation. The primary combined endpoint included 1) death from any cause, 2) HF-related hospitalisations, and 3) NYHA class at 6 months. Before implant, 27 patients had > or =1 echo criterion of mechanical dyssynchrony (DES+ group) and 33 had no evidence of dyssynchrony (DES- group). At 12 months, 8 patients (4 per group) had died, 7 from HF. As regards the primary endpoint at 6 months, 33 patients (55%) had improved, 10 (16%) were unchanged, and 17 (29%) had deteriorated. Clinical improvement was observed in 19 of 27 DES+ (70%), versus 14 of 33 DES- (42%) patients (P<0.04). Baseline QRS duration did not predict response to CRT. CONCLUSIONS: In this population of HF patients with QRS<150 ms, the presence of mechanical dyssynchrony at baseline D-echo examination, but not the QRS width, predicted 6-month clinical response to CRT.  相似文献   

17.
OBJECTIVES: We investigated whether a lack of inertia force of late systolic aortic flow and/or apical asynergy provoke early diastolic dysfunction in patients with coronary artery disease (CAD). BACKGROUND: Left ventricular (LV) isolated diastolic dysfunction is a well-recognized cause of heart failure. METHODS: We evaluated LV apical wall motion and obtained left ventricular ejection fraction (LVEF) by left ventriculography in 101 patients who underwent cardiac catheterization to assess CAD. We also computed the LV relaxation time constant (Tp) and the inertia force of late systolic aortic flow from the LV pressure (P)-first derivative of left ventricular pressure (dP/dt) relation. Using color Doppler echocardiography, we measured the propagation velocity of LV early diastolic filling flow (Vp). Patients with LVEF > or =50% (preserved systolic function [PSF], n = 83) were divided into 2 subgroups: patients with inertia force (n = 53) and without inertia force (n = 30). No patient with systolic dysfunction (SDF) (LVEF <50%) had inertia force (n = 18). RESULTS: The Tp was significantly longer in patients with SDF (85.7 +/- 21.0 ms) and with PSF without inertia force (81.1 +/- 23.6 ms) than in those with PSF with inertia force (66.3 +/- 12.8 ms) (p< 0.001). The Vp was significantly less in the former 2 groups than in the last group. In patients with PSF, LV apical wall motion abnormality was less frequently observed in those with inertia force than in those without (p < 0.0001). CONCLUSIONS: An absence of inertia force in patients with PSF is one of the causes of isolated diastolic dysfunction in patients with CAD. Normal LV apical wall motion is substantial enough to give inertia to late systolic aortic flow.  相似文献   

18.
BACKGROUND: Cardiac resynchronization therapy (CRT) is useful for the treatment of severe congestive heart failure. Unfortunately up to 30% of patients could be non-responders. The aim of our study was to find parameters to predict responsiveness to CRT. METHODS: Fifteen patients (9 males, 6 females, mean age 67.3 +/- 7.8 years, range 52-83 years) with dilated cardiomyopathy, NYHA functional class III-IV, left ventricular (LV) ejection fraction < 35% and QRS > or = 110 ms, underwent CRT. All the patients had echocardiographic evidence of systolic dys-synchrony. RESULTS: One patient died of electromechanical dissociation. The remaining 14 patients maintained biventricular stimulation at 6 months; mean QRS width decreased from 156 to 132 ms (p < 0.001). Ten patients (71%) were considered responders because of a reduction in LV end-systolic volume > 15%. In non-responders (4 patients, 29%) LV end-systolic volume was stable in 3 patients and increased in 1. LV ejection fraction significantly increased only in responders (p < 0.001). Responders had more severe pre-pacing dyssynchrony than non-responders (p < 0.001). Inter- (p = 0.002) and intraventricular dyssynchrony (p = 0.003) did significantly reduce after CRT only in responders. On multiple regression analysis there were two independent predictors of reverse remodeling after pacing: the baseline mitral QS-tricuspid QS (QSm-QSt) time (B = -1.7, p = 0.005) and the intraventricular dyssynchrony index (B = -1.55, p = 0.007). Pre-implant QSm-QSt of 38 ms correctly identified the two groups: responders had a value > 38 ms and non-responders < 38 ms. The pre-implant intraventricular dyssynchrony index of 28 ms was the cut-off value: responders had an index > 28 ms, non-responders < 28 ms. CONCLUSIONS: In the literature a tissue Doppler imaging index of intraventricular dyssynchrony evaluated before implantation is used to select responders to CRT. In our work we studied interventricular and intraventricular dyssynchrony, and both the QSm-QSt time and the standard deviation of the 12 LV segment QS time were correctly able to identify responders.  相似文献   

19.
Purpose: To assess left ventricular mechanical dyssynchrony (LVMD) using real time three‐dimensional echocardiography (RT3DE) and comparing it with the different dyssynchrony indices derived from Doppler tissue imaging (DTI) for the same patient. Methods: The study included 60 consecutive patients who were considered candidates for CRT, i.e., having ejection fraction ≤35%, NYHA class III or ambulatory class IV, QRS duration ≥120 msec, on optimal pharmacological therapy. Apical RT3DE full volumes were obtained and analyzed to generate the systolic dyssynchrony index (SDI‐16), which is the standard deviation of the time to minimal systolic volume of the 16 segments of LV. Color‐coded DTI was performed for the three standard apical views with estimation of the mechanical dyssynchrony index (12 Ts‐SD), which is the standard deviation of the time to peak systolic velocity at 12 segments of LV. Results: SDI‐16 was 10.96 ± 3.9% (cutoff value: 8.3%), while Ts‐SD was 38 ± 10.2 msec (cutoff value: 32.6 msec). The concordance rate for both indices was 75%; however, there was no correlation between both indices (r = 0.14, P = 0.3). SDI‐16 showed good correlation with QRS duration (r = 0.45, P < 0.001) and inverse correlation with left ventricular ejection fraction (LVEF) calculated by RT3DE (r =?0.37, P = 0.004), while 12 Ts‐SD index showed no correlation with QRS duration (r =?0.0082, P = 0.51) or 2D LVEF (r =?0.26, P = 0.84). Conclusions: RT3DE can quantify LVMD by providing the SDI‐16 and it may prove to be more useful than DTI as it shows increasing dyssynchrony with increased QRS duration and decreased LVEF. (Echocardiography 2012;29:173‐181)  相似文献   

20.
目的:通过分析植入心脏再同步治疗( CRT)术后QRS时限( QRSd)的变化,评估术后不同的QRSd对CRT长期预后的影响。方法2001年4月至2012年3月来自沈阳军区总医院及白求恩国际和平医院住院并植入CRT的心力衰竭患者164例,按术后QRSd变化分为3组:Ⅰ组:107例( QRSd术前〉术后),Ⅱ组:30例( QRSd术前〈术后),Ⅲ组:27例( QRSd术前=术后)。观察术后3组病死率及心功能指标变化。结果随访48个月,3组患者的病死率及死因差异无统计学意义( P〉0.05)。Ⅰ组和Ⅲ组术后心功能及左心室射血分数(LVEF)较Ⅱ组明显改善(P〈0.05-0.01),且左心室舒张末期内径( LVEDD)明显缩小( P〈0.05-0.01)。Ⅱ组术后心功能及 LVEF也明显改善( P〈0.05-0.01),但LVEDD无明显缩小(P〉0.05)。术后QRSd较术前变宽或变窄与术前QRSd的基础值有关,术前QRSd〈140 ms是术后QRSd变宽的影响因素。结论术后QRSd变化对预后影响不同,QRSd变窄患者不但临床心功能恢复的较好,而且还可有明显的左心室逆重构,更奠定了长期心功能改善的基础。术后QRSd变化与术前QRSd有明显关系,术前QRSd〈140 ms时,术后QRSd变窄的几率小,因此,术前QRSd越宽,术后QRSd变窄的效果越好。  相似文献   

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