高血压病对左室功能的影响

目的探讨高血压病患者心脏左室功能的改变. 方法应用超声心动图及组织多普勒显像(DTI)检测74例高血压病患者及94例正常对照者左室收缩及舒张功能. 结果高血压病组左室质量指数、跨二尖瓣血流频谱速度A及E/A比值和DTI频谱速度s、a及e/a比值较正常组有显著差异(P＜0.05),但左室射血分数(LVEF)、跨二尖瓣血流频谱速度E和DTI频谱速度e在高血压病组及正常组间无显著差异(P＞0.05);DTI的收缩期峰速度与LVEF和舒张期峰速度比值e/a与E/A在两组间均呈显著相关(P＜0.05). 结论高血压病患者收缩期峰速度s及舒张晚期峰速度a增加,提示左室收缩功能增强,左室僵硬度增加,左房辅助泵功能增强;DTI能早期、敏感地发现高血压病患者收缩及舒张功能的改变.     

冠脏病变对心脏左室舒缩功能的影响

目的：通过超声心动图检查，探讨冠脏病变对左室收缩，舒张功能的影响。方法：67例行冠状动脉造影检查，据检查结果被分成冠心病组（46例），正常对照组（25例），分别行超声心动图检查，测量其每搏量，心输出量，左室短轴缩短率，射血分数，二尖瓣口E，A峰血流速度（E，A峰值）及E／A比值。结果：与正常对照组比较，冠心病组收缩功能指标中每搏量增加（P＜0．01）。舒张功能指标中E峰降低（P＜0．05），A峰升高（P＜0．01），E／A比值降低（P＜0．01）。结论：冠脉病变影响心脏功能，早期先影响舒张功能。     

二维多普勒超声对中年和老年人高血压性左室肥厚的比较研究

应用二维多普勒超声对36例中年和54例老年人的高血压性在室肥厚（LVH）及心功能状态进行分析比较。结果：中年组LVH类型：不对称性室间隔肥厚(ASH）占40%,对称性肥厚（CH）46％。扩张性肥厚（DH）占14％；老年组：ASH23%，CH26％，DH51％。将中年组和老年组分别同正常对照组比较，除中年组LVDd、LVV、EF及CO差异无显著性外，其余各指标差异均有显著性（P＜0.01或P＜0.O01）。中年组和老年组比较，E峰和A／E比值差异无显著性，其余各指标差异有显著性（P＜0.05或P＜0.O01）。结论认为在左室肥厚早期，左室充盈功能降低，左房增大，左房代偿性收缩增强，向左室泵血增多，以维持恒定的房室压差弥补左室充盈不足，左室收缩功能可表现为正常；在LVH晚期，失代偿后左室收缩及舒张功能均降低。     

美托洛尔对高血压血液动力学的急性效应

用二维及多普勒超声心动图观察30例高血压病患者首次口服美托洛尔后其血液动力学的即刻效应。口服美托洛尔50mg后，血压、心率明显下降，血管顺应性、外周阻力增加；左心形态结构无明显改变；左室收缩功能指标FS、EF、CO、CI明显下降（P＜0．01），左室舒张功能参数E、EI增加，A、AI、A／E、AI／TI明显下降（P＜0．05），提示左室收缩功能减弱，舒张功能改善。     

长期应用依那普利对高血压病患者左室结构及功能影响

观察了28例Ⅱ期高血压病患者平均口服依那普利平均22个月后左室结构及功能改变。结果显示：用药后血压降低总有效率为89．3％，心率无变化。用药后空间隔、左室后壁及左定重量指数均明显下降（P＜0．05），A峰速度及A／E比值明显下降，E峰速度明显增高（P＜0．05）。提示：依那曾利长期治疗可有效降压，并同时逆转左室肥厚，改善左室舒张功能。     

高血压右室与左室舒张功能的关系

对64例Ⅰ、Ⅱ期临床无心功能不全表现的高血压患者，32例年龄与性别相匹配的健康者，应用多普勒超声心动图技术，对其右室舒张功能进行测定，同时测定其左室收缩及舒张功能并作比较，高血压组按超声心动图标准分为左室肥厚组（LVH）34例，无左室肥厚组（NLVH）30例。测定结果表明,NLVH组与正常组比较，前者通过三尖瓣的E峰较低（P＜0.05），A峰较高（P＜0.05），E／A比值较小（P＜O.01)，快速充盈分数(PFF），l／3充盈数(1／3EF）和校正的充盈率峰值（PFR）也降低（P＜0.05），下降时间（DT）延长（P＜0.01）。LVH组中上述各参数与正常组比较也均有降低，与NLVH组比较A峰、E／A比值和PFR有进一步损害。相关分析发现，右室充盈参数与左室充盈参数密切相关（r从0.45到0.80）。     

高血压病对左室功能的影响

目的:探讨高血压病患者心脏左室功能的改变。 方法:应用超声心动图及组织多普勒显像(DTI)检测74例高血压病患者及94例正常对照者左室收缩及舒张功能。 结果:高血压病组左室质量指数、跨二尖瓣血流频谱速度A及E/A比值和DTI频谱速度s、a及e/a比值较正常组有显著差异(P<0.05),但左室射血分数(LVEF)、跨二尖瓣血流频谱速度E和DTI频谱速度e在高血压病组及正常组间无显著差异(P>0.05);DTI的收缩期峰速度与LVEF和舒张期峰速度比值e/a与E/A在两组间均呈显著相关(P<0.05)。 结论:高血压痛患者收缩期峰速度s及舒张晚期峰速度a增加,提示左室收缩功能增强,左室僵硬度增加,左房辅助泵功能增强;DTI能早期、敏感地发现高血压病患者收缩及舒张功能的改变。     

血浆胰岛素及血糖水平对老年高血压左室舒张功能的影响

目的：探讨血糖、胰岛素水平和肥胖对老年高血压病心肌舒张功能的影响。方法：检测36例正常老年者、28例单纯肥胖者、38例高血压者及42例高血压合并肥胖者的血糖、胰岛素及糖化血红蛋白浓度，4组中各有20例做口服葡萄糖耐量及胰岛素释放试验；均行超声心动图检查。结果：各组射血分数和心脏指数均正常。高血压病组E／A比值明显下降而等容舒张时间明显延长，以合并肥胖者尤为明显（均P＜0．005）。E／A值与空腹血糖相关（γ=0．67，P＜0．005）；与血浆胰岛素及左室重量无关。结论：肥胖及糖耐量异常可加重老年高血压病患者左室舒张功能障碍。     

美托洛尔对高血压患者左室肥厚及心功能的影响

对高血压病患者54例应用美托洛尔口服，血压稳定后改为维持量随访观察治疗3～4个月，HR，SBP，DBP，MAP及TPR均降低（P＜0．01），总有效率为87％；左室形态结构指标（LAD，LVD，LVMI）显著改善（P＜0．05～0．01）；左室舒张功能指标（A，E，A／E，PFR及NPFR）显著改善（P＜0．05）；左室收缩功能指标（SV，EF及CO）无变化（P＞0．05）。     

高血压心脏病左心房收缩功能的超声心动图评价

目的应用超声心动图技术分析高血压病人的左心房收缩功能。方法60例高血压患者、20例健康对照者。根据左室质量指数将高血压病人分为左室构型正常组及左室肥厚组，取组织多普勒的速度模式，将取样容积放在二尖瓣瓣环处，测量心房收缩期的组织运动速度(A’)、衡量其与传统的评价左心房功能的参数如左房射血力、左房动能等的相关性。结果伴随高血压病情的加重，A’、心房收缩期血流峰值速度(A)、LAEF、LASV、左房射血力、左房动能明显增加，高血压组、左室肥厚组、左室构型正常组与健康对照组差异有显著性意义(P＜O．01)；A’与LAEF(r=O．81，P＜O．01)，LASV(r=O．73，P＜O．01，左房射血力(r=O．84，P＜O．01)，左房动能(r=O．81，P＜O．01)呈高度正相关。结论QTVI技术测定的A’是评价高血压病左心房收缩功能有意义的指标。     

Left atrial systolic time intervals: their relations to left atrial preload, afterload and acute left ventricular pressure loading

Using pulsed Doppler echocardiography, the left atrial pre-ejection period (LAPEP) and left atrial ejection time (LAET) were studied in relation to left atrial loading and acute left ventricular pressure loading conditions in 17 patients with various heart diseases. LAPEP was defined as the time interval from the onset of a right atrial pacing pulse to the upstroke in the atrial contraction phase on the mitral flow velocity pattern; LAET was defined as the duration of left ventricular filling due to atrial contraction. 1. LAPEP did not correlate significantly with mean pulmonary capillary wedge pressure (mPCWP) indicating preload for the left atrium, nor with left ventricular end-diastolic pressure (LVEDP) indicating afterload for the left atrium. There were significant inverse correlations of LAET with mPCWP (r = -0.72) and with LVEDP (r = -0.75). 2. LAPEP, LAET and LAPEP/LAET correlated significantly with the ratio of the peak velocity in the atrial contraction phase and to that in the rapid filling phase (r = -0.62, -0.50 and -0.59, respectively). There was a significant inverse correlation of LAPEP/LAET with the left ventricular ejection fraction (r = -0.62). 3. When left ventricular systolic pressure became elevated by 25% of its basal value at a constant right atrial pacing rate, LAPEP decreased from 110 +/- 21 msec to 103 +/- 22 msec (p less than 0.05), LAET increased from 123 +/- 33 msec to 129 +/- 24 msec and LAPEP/LAET decreased from 0.95 +/- 0.37 to 0.84 +/- 0.32 (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)     

Determinants of left atrial systolic time intervals--assessment by pulsed Doppler echocardiography

To evaluate the responsible factors for left atrial ejection, the left atrial preejection period (LAPEP), i.e., the time interval between atrial pacing pulse and onset of atrial ejection, and left atrial ejection time (LAET), i.e., the duration of atrial ejection, were determined from mitral inflow velocity patterns in 35 patients with various heart diseases using pulsed Doppler echocardiography. LAPEP ranged from 75 to 157 (mean 110 +/- 18) msec and LAET from 80 to 169 (mean 124 +/- 19) msec. The left atrial dimension before atrial contraction showed no significant correlation with LAPEP or LAET. Peak velocity during atrial contraction was negatively correlated with LAPEP (r = -0.42, p less than 0.05) and positively with LAET (r = 0.56, p less than 0.01). Left ventricular end-diastolic pressure (LVEDP) indicated a significant negative linear correlation with LAET (r = -0.44, p less than 0.05). LAPEP showed no significant linear correlation with LVEDP, but a significant curvilinear relationship was observed between them (LAPEP = 169 - 9.LVEDP + 0.28.LVEDP2, r = 0.63, p less than 0.001). Mean pulmonary capillary wedge pressure (mPCWP) was curvilinearly related to LAPEP (LAPEP = 168 - 11.mPCWP + 0.42.mPCWP2, r = 0.72, p less than 0.001) and LAET (111 + 4.1.mPCWP - 0.22.mPCWP2, r = 0.63, p less than 0.001). Although LAPEP decreased and LAET increased with increase in mPCWP up to about 15 mmHg, the reverse situation was noted for greater mPCWP. Thus, the major determinants of left atrial systolic time intervals are left atrial and ventricular pressures, and peak velocity during atrial contraction.     

Left atrial systolic time interval in hyperthyroidism.

The author noninvasively examined effects of thyroid hormone on left atrial function by using the left atrial systolic time intervals (LASTI) with its parameters as left atrial ejection time (LAET), left atrial preejection period (LAPEP), and LAET/LAPEP, as measured by pulsed Doppler echocardiography. The hyperthyroid (HTH) and normal control (NC) groups consisted of 21 and 25 subjects, respectively. He also considered serum triiodothyronine (T3) concentrations, age, heart rate, systolic blood pressure, left ventricular preload, afterload, contractility, diastolic function, P wave duration, PR interval, and left ventricular preejection period (LVPEP) as factors that might influence LASTI. LAET, LAET/LAPEP, and LVPEP in the HTH group were significantly shorter than in the NC group. LAET showed no significance with serum T3 concentration, but did with LVPEP in partial correlation analysis. These results demonstrated that a short LAET in the hyperthyroid state is controlled by a rapid rise in the left ventricular pressure.     

Left atrial systolic force in hypertensive patients with left ventricular hypertrophy: the LIFE study

In hypertensive patients without prevalent cardiovascular disease, enhanced left atrial systolic force is associated with left ventricular hypertrophy and increased preload. It also predicts cardiovascular events in a population with high prevalence of obesity. Relations between left atrial systolic force and left ventricular geometry and function have not been investigated in high-risk hypertrophic hypertensive patients. Participants in the Losartan Intervention For Endpoint reduction in hypertension echocardiography substudy without prevalent cardiovascular disease or atrial fibrillation (n = 567) underwent standard Doppler echocardiography. Left atrial systolic force was obtained from the mitral orifice area and Doppler mitral peak A velocity. Patients were divided into groups with normal or increased left atrial systolic force (>14.33 kdyn). Left atrial systolic force was high in 297 patients (52.3%), who were older and had higher body mass index and heart rate (all P < 0.01) but similar systolic and diastolic blood pressure, in comparison with patients with normal left atrial systolic force. After controlling for confounders, increased left atrial systolic force was associated with larger left ventricular diameter and higher left ventricular mass index (both P < 0.01). Prevalence of left ventricular hypertrophy was greater (84 vs. 64%; P < 0.001). Participants with increased left atrial systolic force exhibited normal ejection fraction; higher stroke volume, cardiac output, transmitral peak E velocities and peak A velocities; and lower E/A ratio (all P < 0.01). Enhanced left atrial systolic force identifies hypertensive patients with greater left ventricular mass and prevalence of left ventricular hypertrophy, but normal left ventricular chamber systolic function with increased transmitral flow gradient occurring during early filling, consistent with increased preload.     

Assessment of left atrial input impedance in normal subjects and in hypertensive patients

BACKGROUND: To assess left atrial (LA) input impedance in patients with signs and/or symptoms of heart failure and normal left ventricular ejection fraction, transesophageal Doppler pulmonary venous (PV) flow velocity and pulmonary capillary wedge pressure (PCWP) were studied in 20 patients and compared to 20 matched normal controls. METHODS: LA impedance was calculated as the ratio of harmonic terms of the PCWP (measured by right heart catheterization) to the corresponding harmonic terms of PV flow (measured by transesophageal Doppler echocardiography). Eight harmonics were analyzed. RESULTS: Left ventricular mass index (LVMI, p<0.001), heart rate (p<0.05), systolic and diastolic blood pressure (p<0.001), isovolumic relaxation time (IVRT, p<0.001), peak A transmitral flow velocity (p<0.001), peak reversal atrial PV flow velocity (p<0.001) and LA diameter (p<0.001) were increased in patients compared to controls. Spectra of impedance moduli were displaced upwards and to the right. The increase in the impedance moduli was observed at all frequencies of the first to seventh harmonic components (p<0.001). In multivariate tests LVMI (p=0.003), IVRT (p=0.001), and LA diameter (p=0.007) had a significant effect on all harmonic components of the impedance moduli (adjusted R2=0.970 to 0.999, p<0.001). CONCLUSIONS: LA input impedance derived from data obtained invasively and semi-invasively represents left ventricular diastolic function. Resistance to left ventricular filling is increased in hypertensive patients.     

Role of left atrial booster pump function in a worsening course of congestive heart failure.

We evaluated changes in left ventricular (LV) preload and the Doppler-derived transmitral late to early diastolic peak velocity ratio (A/E ratio) during the exercise in 27 patients with ischemic heart disease. After the exercise, A/E ratio decreased in 16 patients with a remarkable elevation in LV preload, and increased in 11 with a mild elevation. Further, Doppler transmitral flow in conjunction with pulmonary venous flow and hemodynamic parameters were analyzed in 11 dogs during a worsening course of heart failure induced by dextran infusion. The relationship of A/E ratio to LV end-diastolic pressure showed a quadratic curve concave to the pressure axis. A/E ratio, an index expressing left atrial (LA) contribution to LV filling, returned to that seen before volume loading under the condition of cardiac dysfunction. Pulmonary venous reflux fraction determined as the ratio of peak velocity of pulmonary venous reflux during LA systole to the sum of systolic and diastolic peak velocities of pulmonary venous antegrade flow, did not increase here. In this situation, blood could not be ejected from the left atrium into the left ventricle and even into the pulmonary veins during LA contraction. Finally, LV filling was not compensated by the left atrium, and LA booster pump function itself was deteriorated.     

Left atrial anatomy and function after conversion from atrial fibrillation in hypertrophic hearts

The aim of the study was to evaluate the influence of left ventricular (LV) hypertrophy on left atrial (LA) electrical and mechanical function after cardioversion atrial fibrillation (A-Fib) of brief duration. Study group A included 100 patients with a first diagnosis of hypertension who had a moderate LV hypertrophy. The patient population included 64 men and 36 women with a mean age of 55 +/-7 years who were hospitalized because of A-Fib and were cardioverted with external DC shock. Control group B included 100 patients without cardiac hypertrophy cardioverted because of lone A-Fib. Atrial function and size were assessed by Doppler echocardiography and the following parameters were measured: transmitral peak A velocity, atrial filling fraction, atrial ejection force, peak E velocity, deceleration time, and isovolumic relaxation time, LA maximal and minimal volume, and LV cardiac mass index. Baseline echocardiography showed that LA diameters and volumes were enlarged in all patients during A-Fib. After the restoration of sinus rhythm LA diameters and volumes decreased and the reduction was more evident in group B compared to group A. LA function as a continuous variable was negatively related to LV mass index (r = -0.77), LA diameter (r = -0.66 and r = -0.69 for the superoinferior diameter), LA maximal volume (r = -0.61) and LA minimal volume (r = -0.55) (all p<0.01). Atrial ejection force as a continuous variable was positively related to age (r =0.78), peak A wave velocity (r =0.71), systolic blood pressure (r =0.51), and IVRT (r =0.41) (all p<0.01). Hypertrophy influenced the recovery of atrial function after cardioversion of A-Fib. Atrial function was reduced in patients with LV hypertrophy even after A-Fib of brief duration.     

Abnormal diastolic function in patients with type 1 diabetes and early nephropathy.

Left ventricular diastolic function was assessed by pulsed Doppler echocardiography in non-diabetic controls (n = 11) and in patients with type 1 diabetes without microvascular disease (n = 16; diabetic controls), with microalbuminuria (n = 9), or with early persistent proteinuria (n = 11). The peak filling velocities during the early and atrial phases of left ventricular diastole and their ratio (E:A ratio) were measured. All patients with diabetes had a normal serum concentration of creatinine and exercise electrocardiogram. The mean E:A ratio was significantly lower in those with proteinuria than in the diabetic controls because of an increase in peak atrial filling velocity; most patients with proteinuria had an abnormal E:A ratio of less than 1.0. Multiple regression analysis showed that systolic blood pressure was the major determinant of both the peak filling velocity during the atrial phase of diastole and also left ventricular mass. Blood pressures were significantly higher in the proteinuria group than in the diabetic controls. Glycaemic control and autonomic function did not influence diastolic filling. The slightly raised blood pressures at the earliest stages of diabetic nephropathy are sufficient to alter left ventricular diastolic compliance--this may reflect early hypertensive heart disease. These data do not preclude a specific heart muscle disease related to diabetes, but suggest that these slightly raised blood pressures contribute significantly to left ventricular dysfunction in these patients, in whom the risk of cardiovascular disease is already greatly increased.     

高血压病患者左室舒张功能不全与U波关系探讨

目的 探讨高血压患者左室舒张功能不全与U波的关系。方法 用超声心动图对104例高压病患者的舒张早期最大峰值速度（E峰）,舒张晚期最大峰速度（A峰）,左室射血分数（LVEF）,左房内径进行测量。将其分为左室舒张功能正常及左室舒张功能不全组。另有46个年龄相当的正常人作为对照组。对所有病人及对照组行常规心电图检查,分析U波形态。结果 左室舒张功能不全的U波倒置发生率明显高于左室舒张功能正常组及正常对照组（24％vs 15% and 13%),前者与后二者相比有显著性差异（P＜0．01）。结论 U波倒置可能是高血压病左室舒张功能不全的标志之一。