应用超声斑点追踪成像技术研究缺血心肌的收缩期峰值圆周应变的变化规律

目的:应用超声斑点追踪成像技术研究心肌缺血患者的左心室各节段心肌收缩期峰值圆周应变的变化规律,探讨其诊断心肌缺血的临床应用价值.方法:应用超声心动图仪获得31例对照组及56例冠心病(组)患者的高频帧二维图像,用二维斑点追踪软件测量左心室短轴基底部及乳头肌水平的收缩期峰值圆周应变.结果:与对照组比较,冠心病组冠脉狭窄50%～75%者后壁基底段、间隔基底段、前间隔基底段、后壁中间段减低,差异均有统计学意义(P<0.05).与对照组比较,冠心病组冠脉狭窄76%～98%者侧壁基底段、后壁基底段、下壁基底段、间隔基底段、前间隔基底段、前壁中间段、侧壁中间段、后壁中间段、前间隔中间段减低,差异均有统计学意义(P<0.05～0.01).与对照组比较,冠心病组冠脉次全及完全闭塞者各节段均减低,差异均有统计学意义(P<0.05～0.01).相关分析显示冠状动脉狭窄程度与乳头肌各节段心肌平均收缩期峰值圆周应变绝对值呈负相关(r=0.547,P<0.01).结论:当冠状动脉高度狭窄时,二维超声心动图无明显改变,但收缩期峰值圆周应变已明显降低.超声斑点追踪成像技术能精确评价缺血心肌的局部应变功能.     

组织速度成像评价经皮冠状动脉介入术前后左室局部收缩功能

目的应用组织速度成像(TVI)技术分析经皮冠状动脉介入术(PCI)前后不同时间点心室心肌纵轴方向运动速度、运动位移、应变、应变率变化规律,研究其评价冠心病(CAD)介入治疗疗效的价值。方法对接受PCI治疗的15例冠心病患者于术前、术后1周、术后1个月以及3个月时采用TVI技术检测心室各节段心肌收缩期纵轴方向运动速度及运动位移、组织形变及形变速率,并比较术前及术后不同时间点差异。结果术前、术后定量组织速度成像(QTVI)、组织追踪成像(TTI)、应变(SI)及应变率成像(SRI)曲线各节段收缩期峰值参数随着时间的延长逐渐增高。与术前比较,术后1个月2个节段(前壁基底段与中间段)收缩期峰值速度(SV)、收缩期峰值位移(SD)增高(P<0.05);术后3个月,8个节段(除前间隔心尖段、侧壁心尖段、后间隔心尖段)SV、SD增高更为显著(P<0.05)。术后3个月6个节段(前间隔基底段及中间段、前壁基底段及中间段、后间隔中间段、后壁心尖段)SV、SD与术后1周相比明显增高(P<0.05)。与术前比较,术后1周3个节段(前壁基底段、中间段、心尖段)收缩期最大应变值(S)及SRI的收缩期最大应变率值(SR)增高(P<0.05);术后1个月5个节段(前壁基底段、中间段、心尖段及前间隔基底段、中间段)S、SR增高(P<0.05)。术后3个月9个节段(除侧壁心尖段、后间隔心尖段)S、SR与术前、术后1周相比均明显增高(P<0.05)。结论 TVI技术能准确地定量评价冠心病患者缺血心肌的局部功能,动态观察PCI前、后局部心肌功能变化,可评价PCI的治疗效果。     

面积应变定量评价无室壁运动异常的左心室缺血心肌的局部功能

目的利用三维斑点追踪成像面积应变评价常规超声心动图检查无明显节段性室壁运动异常的左心室缺血心肌的局部功能。方法本研究包括30例对照组和78例病例组,常规超声心动图检查左心室未见明显节段性运动异常,冠状动脉造影检查对照组所有分支狭窄均小于50%,病例组至少一条主要分支狭窄大于70%,利用三维斑点追踪成像测量左心室17节段的面积应变,比较缺血心肌节段和正常心肌节段面积应变的差异。结果左前降支供血区域前壁中间段、前间隔基底段与中间段、心尖部面积应变和平均面积应变较对照组明显减低(P0.05);左回旋支供血区域侧壁心尖段、后壁基底段与中间段面积应变和平均面积应变较对照组明显减低(P0.05);右冠状动脉供血区域下壁中间段与心尖段面积应变和平均面积应变较对照组明显减低(P0.05)。结论面积应变是可以作为定量评价左心室局部心肌功能的一种可用指标。     

二维斑点成像技术评价扩张型心肌病患者心脏的纵向扭转

目的 运用二维斑点成像技术评价扩张型心肌病患者(dilated cardiomyopathy,DCM)与健康人间各参数的差异,证实DCM患者心脏纵向扭转的存在.方法 搜集温州医学院附属第一医院2008年6月至2009年9月期间就诊的42例DCM患者作为DCM组和35例健康人作为对照组.两组均行常规超声心动图,检测左心房内径、左心室射血分数、过二尖瓣口舒张早期血流速度及舒张晚期血流速度.应用GE Echopac软件测量得到DCM组和对照组患者心尖四腔心的左心室壁的径向应变、应变率,左心室侧壁、室间隔、心尖及左心室整体纵向峰值扭转角度,对比两组间各参数的差异.结果 (1) DCM组患者左心房内径、左心室收缩末期容积及左心室舒张末期容积均明显大于对照组(P均＜0.01),左心室射血分数明显低于对照组(P＜0.0l),过二尖瓣口舒张早期血流峰速度/舒张晚期血流峰速度两组比较差异无统计学意义(P＞0.05).(2) DCM组患者径向收缩期峰值应变以及收缩期、舒张早期、舒张晚期径向峰值应变率均明显低于对照组(P均＜0.01).(3)对照组左心室侧壁的中间段、基底段以及心尖段呈逆时针扭转,而室间隔的基底段、中间段呈顺时针扭转,DCM组患者左心室侧壁的中间段呈逆时针扭转,而左心室侧壁基底段、心尖段、室间隔的基底段及中间段均呈顺时针扭转.DCM组患者左心室侧壁中间段和基底段、心尖段以及室间隔基底段的扭转角度均明显低于对照组(P均＜0.01).对照组左心室呈较小角度的纵向逆时针扭转(0.76°±2.63°),而DCM组患者左心室呈纵向顺时针扭转(- 1.58°±3.42°),两组扭转角度的差异有统计学意义(P＜0.01).(4)DCM组患者左心室侧壁基底段、中间段与室间隔基底段扭转达峰时间差均与左心室的纵向峰值扭转角度具有相关性(r=0.409,P=0.007; r=0.396,P=0.009).结论 应用二维斑点成像技术,通过分析各节段应变、应变率及纵向扭转角度等参数,证实DCM患者心脏存在着一定角度的纵向顺时针扭转,DCM患者左心室侧壁基底段、中间段与室间隔基底段扭转达峰时间差可能是形成DCM患者心脏纵向扭转的一个原因.     

四种超声心动图技术评价正常人心肌生物力学参数及其与心功能相关关系

目的: 比较直接二维测量法(D2D)、解剖M型(AMM)、组织速度成像技术(TVI)及二维斑点追踪技术(STI)评价正常人心肌生物力学参数及其与心功能相关关系的方法,比较他们在临床运用过程优点及存在问题。方法: 分别应用D2D、AMM、TVI及STI测量并比较40例正常人收缩、舒张期心肌在长轴方向、短轴和圆周方向的心脏生物力学参数。结果: D2D显示:正常人收缩期纵向应变(LS)及应变率(LSR):下壁>后间隔>前间隔>后壁>前壁>侧壁（P>005）;收缩期LS、LSR与左室射血分数（LVEF）相关系数(r)分别为-0523及-0550。AMM显示:正常人收缩末期径向应变(RS)及径向应变率(RSR)游离壁大于间隔:收缩期RS、RSR与左LVEF(r)分别为0533及0495。TVI显示:收缩期LS:心尖段<基底段、中间段(P<005);舒张早期LS中间段>基底段>心尖段;舒张晚期LS心尖段<基底段、中间段(P<005);收缩期LS、LSR与LVEF(r)分别为-0562及-0550。STI显示:收缩期LS从基底段到心尖段逐步递增;左室扭转运动表现为心底部顺时针旋转和心尖部逆时针旋转,心脏整体表现为心动周期内逆时针方向为主的扭转运动。心肌收缩期平均LS及LSR与左室收缩功能参数间r的绝对值均超过055。结论: D2D通过直接测量左室长轴方向心肌长度的变化,间接计算LS与LSR;AMM克服了M型超声测量的角度限制,比较适合体位不合作的患者;TVI适合评价长轴方向室壁运动特征;STI对二维图像的超声斑点回声进行逐帧追踪,可以更准确测量局部室壁V、S等参数,定量评价局部心肌的收缩和舒张功能,测量参数与传统超声测量LVEF相关性较好,但设备要求较高。     

组织速度成像评价冠心病不同程度缺血心肌的左室局部收缩功能

目的 应用组织速度成像技术分析冠心病(CAD)不同程度冠脉狭窄缺血心肌及心梗后缺血心肌纵轴方向运动速度、运动位移、应变及应变率的特点,评价其对不同程度心肌缺血的诊断价值.方法 对72例CAD患者采用TVI技术检测心室各节段心肌收缩期纵轴方向运动速度及运动位移、组织形变及形变速率,并比较定量组织速度成像(QTVI)、组织追踪成像(TTI)、应变(SI)及应变率成像(SRI),检测冠心病心肌缺血的临床应用价值.结果 随着冠状动脉左前降支狭窄程度加重,TVI各曲线变得紊乱,收缩期波峰显著降低,非心梗1级组、2 级组、3级组及心梗组各收缩期峰值参数逐渐降低,心梗组明显下降(P<0.05).运动立称(SD)、运动速度(SV)各组间比较:心梗组与非心梗1级组、心梗组与非心梗2级组比较,左前降支所支配的各基底段、中间段及前壁心尖段SV、SD均降低(P<0.05);非心梗3级组与1级组比较,3个节段(前间隔基底段、前壁基底段及中间段)SV、SD降低(P<0.05);心梗组与非心梗3级组比较,11个节段SV、SD降低(P>0.05).S、SR各组间比较:心梗组与非心梗1级组比较,11个节段组织应变(S)、应变速度(SR)降低(P<0.05);心梗组与非心梗2级组比较,除侧壁心尖段外,余10个节段S、SR降低(P<0.05);心梗组与非心梗3级组比较,5个节段(前间隔基底段、中间段及前壁基底段、中间段、心尖段)S、SR降低(P<0.05);非心梗3级组与1级组比较,5个节段(前间隔基底段、中间段及前壁基底段、中间段、心尖段)S、SR降低(P<0.05).结论 随着冠状动脉狭窄程度加重,缺血心肌节段的定量组织速度成像、组织追踪成像、应变及应变率成像四项收缩期峰值参数逐渐减低,有一定的变化规律.     

二维斑点追踪成像技术评估肥厚型心肌病患者左心房功能

目的：通探讨二维斑点追踪技术（2D-STI）评价肥厚型心肌病（HCM）患者左心房功能的价值。方法：HCM患者61例，其中梗阻性肥厚型心肌病31例和非梗阻性30例，同期健康对照组30例。应用2D-STI技术,获取左心房整体及节段纵向应变，并比较三组间的差异。结果：(1)梗阻组、非梗阻组的储备功能（LASr）、管道功能（LAScd）、辅泵功能（LASct）均较对照组减低，且梗阻组LASr、LAScd较非梗阻组减低，差异有统计学意义（均P<0.05）；梗阻组LASct与非梗阻组差异无统计学意义（P>0.05）。(2)梗阻组、非梗阻组左心室收缩末期左侧壁纵向应变（ES-LWLS）、左侧壁纵向峰值应变（P-LWLS）、左心室收缩末期房顶部纵向应变（ES-RLS）、房顶部纵向峰值应变（P-RLS）、左心室收缩末期右侧壁纵向应变（ES-RWLS）、右侧壁纵向峰值应变（P-RWLS）均较对照组降低，且梗阻组较非梗阻组降低（均P<0.05）。结论：二维斑点追踪可无创、准确、迅速的评价HCM患者左心房的整体与节段功能。     

超声斑点追踪技术在评价心肌梗死患者左室径向收缩功能中的应用

目的探讨超声斑点追踪技术（STI）诊断节段性室壁运动异常及评价左室收缩功能的临床应用价值。方法对30例心肌梗死患者（心梗组）和30例查体健康者（对照组）应用超声心动图仪获得高频帧二维图像,使用二维应变软件检测左室短轴三个水平（二尖瓣、乳头肌、心尖）各节段心肌的峰值径向应变（SR）及应变率（SRs）。结果心梗组梗死节段峰值SR和SRs在乳头肌水平各节段心肌均显著低于对照组（P均〈0.01）,而二尖瓣水平、心尖水平只有前间隔、前壁、侧壁、后间隔不同程度低于对照组（P〈0.05）,三个水平节段心肌与对照组比较均有显著性差异（P〈0.01）,SRs、SR均与LVEF明显相关（r分别=0.608、0.375,P分别〈0.01、0.05）。结论 STI能准确评价节段性室壁运动异常,可作为临床评价心肌梗死患者左室收缩功能的一种更科学、更客观的方法。     

二维斑点追踪技术在评价2型糖尿病患者早期左心房功能中的应用

目的:应用二维斑点追踪技术评价2型糖尿病(T2DM)患者早期左心房功能。方法:搜集T2DM患者56例,把其中27例无微血管病者作为A组,29例合并微血管病者作为B组,30例正常健康志愿者作为对照组(C组)。采集静息状态下心尖两腔切面和心尖四腔切面二维动态图像,应用二维斑点追踪技术(2D-STE)技术获取左心房各壁(房间隔、侧壁、下壁及前壁)在左心室收缩期、舒张早期和舒张晚期的峰值应变率及左心房整体应变(SRs、SRe、SRa、Gs),并计算其平均值(mSRs、mSRe、mSRa)。应用实时三维超声技术测得左心房各容积参数、左心房被动射血分数(LAPEF)、左心房主动射血分数(LAAEF)及左房扩张指数(LAEI)。另外,各组均行常规超声心动图检查。结果:与C组比较,A组和B组左心房Gs、mSRs、mSRe降低,mSRa升高(均P0.01)。A和B组mSRa与LAAEF呈显著正相关(r=0.785,0.813,均P0.01)。结论:2D-STE可较好地反映T2DM患者早期左心房功能。     

应用应变及应变率技术评价心力衰竭患者左心室功能

目的探讨采用应变（strain,SRI）及应变率（strain rate,SR）技术评价心力衰竭患者左心室局部心肌收缩、舒张功能。方法选取26例心力衰竭患者及30例正常对照组,采用应变及应变率技术,在心尖四腔切面,将取样点分别放置在后间隔及侧壁的基底段、中段和心尖段心肌,测量收缩期室壁不同节段的心肌应变（SRI）、收缩期应变率（SRS）、舒张早期应变率（SRE）、舒张晚期应变率（SRA）。结果与对照组比较,心力衰竭组各节段的SRI、SRS及SRE显著降低（P<0.05,P<0.01）,各节段间的SRI及SRS阶梯差消失,SRA无显著改变。结论心力衰竭患者存在左心室收缩及舒张障碍,应变及应变率技术不失为无创定量评价的方法。     

二维斑点追踪技术评价社区人群左心房应变率与左心室舒张功能的相关性

目的:应用二维斑点追踪技术评价社区人群左心房应变率,及其与左心室舒张功能分级的相关性。方法:研究对象为左心室射血分数正常的社区人群,共708例脱机处理,根据多普勒二尖瓣口血流、二尖瓣环组织、肺静脉血流对左心室舒张功能进行分组:A组(左心室舒张功能正常组)、B组(左心室舒张功能轻度受损组)、C组(左心室舒张功能中/重度受损组)。采用二维斑点追踪技术(STE),测量收缩期左心房应变率峰值SRs,舒张早期左心房应变率峰值SRe和舒张晚期左心房应变率峰值SRa。结果:①B组、C组SRs较A组降低,分别为(1.07±0.35)s-1、(0.90±0.24)s-1和(1.12±0.28)s-1(P<0.01),B组、C组SRe较A组亦明显降低,分别为(-0.79±0.35)s-1、(-0.65±0.29)s-1和(-1.02±0.33)s-1(P<0.01);SRa在B组高于A组[分别为(-1.60±0.58)s-1和(-1.48±0.47)s-1,P<0.05],亦高于C组[分别为(-1.60±0.58)s-1和(-1.24±0.48)s-1,P<0.01],且C组显著小于A组[分别为(-1.24±0.48)s-1和(-1.48±0.47)s-1,P<0.01]。②SRs、SRe与左心室舒张功能分级均呈负相关(r分别为-0.178和-0.366,P<0.01)。结论:二维斑点追踪技术测量左心房应变率,可间接反映左心室舒张功能。     

Supernormal diastolic function and role of left atrial myocardial deformation analysis by 2D speckle tracking echocardiography in elite soccer players

Purpose: Top‐level training is associated with morphological and functional changes in the heart. Left atrial (LA) enlargement can be regarded as a physiologic adaptation to exercise conditioning. Athletes show an improvement in myocardial diastolic properties and supernormal left ventricular (LV) diastolic function. The aims of the study were to assess diastolic function by pulsed Doppler tissue imaging (DTI) and to analyze the role of LA in athletes by speckle tracking echocardiography (STE). Methods: Twenty‐three male elite soccer players underwent a complete echocardiographic analysis. Twenty‐six age‐matched healthy sedentary men were used as controls. Measured variables included LA indexed volumes, DTI of the LV, peak atrial longitudinal strain, and peak atrial contraction strain (PACS). Results: LA areas and indexed volumes were significantly higher in athletes (P < 0.001). Athletes had a higher peak E velocity (P < 0.001), a lower A peak (P < 0.01), and a higher peak E/A ratio (P < 0.0001); a higher Em peak (P < 0.001), a lower Am peak (P < 0.01), and a higher Em/Am ratio (P < 0.0001). Global PACS was lower in athletes compared with controls (P < 0.0001) and strongly correlated with mitral Am (r = 0.55; P < 0.0001), mitral Em (r =?0.41; P < 0.001), heart rate (r =?0.38; P < 0.01), and LA area (r = 0.18; P < 0.05). Conclusions: Athletes showed a shift in the pattern of ventricular filling period toward early diastole as seen through DTI analysis of the diastolic properties of LV and STE analysis of LA function. DTI is a useful tool to analyze the improved myocardial diastolic properties of athletes and STE may elucidate the role of LA in the context of athlete's heart remodeling. (Echocardiography 2011;28:320‐326)     

Progressive subclinical left ventricular systolic dysfunction in severe aortic regurgitation patients with normal ejection fraction: a 24 months follow-up velocity vector imaging study

Objectives: We aimed to evaluate long‐term changes in left ventricular (LV) longitudinal systolic functions in patients with asymptomatic, severe aortic regurgitation (AR) by using novel 2D strain imaging. Methods and Results: Thirty severe AR patients with normal ejection fraction (EF) and 30 healthy controls were evaluated by both conventional echocardiography and velocity vector maging (VVI) based strain imaging at baseline and 24 months follow‐up. To evaluate LV longitudinal systolic function, segmental peak systolic strain and strain rate (SRs) data were acquired from apical four‐chamber, two‐chamber and long‐axis views. Longitudinal peak systolic strain and SRs of the LV were decreased in patients with severe AR compared to controls at baseline (P = 0.0001). The impairment was more significant in 24 months follow‐up (P = 0.0001 for strain, P = 0.01 for SRs). Longitudinal peak systolic strain was significantly correlated with left ventricular end‐diastolic (LVEDD; r =–0.42, P = 0.0001) and left ventricular end‐systolic diameter (LVESD) (r =–0.41, P = 0.0001) There was also a strong negative correlation between LV SRs and LVEDD (r =–0.50, P = 0.0001), and LVESD (r =–0.39, P = 0.0001). Conclusions: VVI‐derived strain and SRs may be used as adjunctive, noninvasive parameters in the assessment of subclinical LV dysfunction and its progress during clinical follow‐up, in patients with severe AR. (Echocardiography 2011;28:886‐891)     

Echocardiographic assessment of left atrial function for prediction of efficacy of catheter ablation for atrial fibrillation

Proper selection for catheter ablation (CA) for atrial fibrillation (AF) is still an issue. Echocardiographic assessment of left atrium (LA) is complex and challenging. Speckle tracking echocardiography (STE) with recent standardized LA deformation analysis allows for the quantitative assessment of various LA function parameters. We aimed to assess the value of detailed evaluations of LA function using STE in patients with non-valvular AF without structural heart disease to predict the outcomes after CA for AF. Secondary aim was to analyze the prediction of CA efficacy in patients with normal LA dimension in baseline echocardiography.We studied with transthoracic and transesophageal echocardiography 82 patients (58% males, mean age 57.3 ± 9.5 years) with non-valvular paroxysmal AF without structural heart disease scheduled for CA. Peak longitudinal LA strain (LAS) and strain rate (LASR) during the reservoir (r), conduit (cd) and contraction (ct) phases were measured by STE before the procedure. Patients were followed for 1 year using serial 4 to 7 day Holter ECG monitoring.Complete freedom from any AF recurrence was achieved in 44 (54%) patients. All patients had normal left ventricular systolic and diastolic function and 53 (65%) of them had not enlarged LA. In the multivariable logistic regression analysis, global left atrial reservoir strain (LASr) was identified as an independent predictor of CA efficacy (OR [95% CI]: 1.35 [1.17–1.55], P < .0001). The opportunity of CA success was 135 fold higher for each 1% increase in global LASr.The receiver operating characteristic (ROC) analysis identified global LASr and left atrial conduit strain (LAScd) as the most powerful parameters for predicting of CA outcome with an area under the curve of 0.896 and 0.860, respectively, in the whole study group, and 0.922 and 0.938, respectively, in patients with not enlarged LA.In patients with paroxysmal AF and normal standard echocardiographic assessment, parameters reflecting LA compliance - reservoir and conduit strain, are independent and strong predictors of CA outcome.     

Assessment of systolic and diastolic left ventricular and left atrial function using vector velocity imaging in Takotsubo cardiomyopathy

Five adult patients with Takotsubo cardiomyopathy (TC) diagnosed by usual criteria were studied with velocity vector imaging (VVI) on admission and at follow-up, when their LV function had improved, as assessed by 2D TTE wall-motion score (WMS) index. Averaged peak segmental longitudinal strain (S) in systole, and velocity (V) and strain rate (SR) in both systole and diastole were measured from apical 4- (A4C) and 2-chamber views (A2C) in all patients. The data obtained by VVI were analyzed separately for involved and uninvolved segments, which were independently assessed by WMS. In the involved segments, systolic S, V, SR, and diastolic SR improved (P-value < 0.05) on follow-up. Diastolic V showed a trend toward improvement but did not reach statistical significance. In the uninvolved segments, none of the parameters improved significantly either during systole or diastole. In three of these five patients, left atrial (LA) walls were also studied by placing region of interest (ROI) points in the middle of each wall. Peak segmental LA systolic and diastolic V and SR as well as systolic S were obtained for both involved and uninvolved LA walls which were assessed independently using WMS similar to LV. In the involved LA walls, none of the atrial systolic and diastolic parameters changed significantly but all parameters with the exception of systolic V showed a tendency toward improvement during follow-up. Among the uninvolved LA walls, none changed significantly but atrial systolic SR and, diastolic V and SR tended to increase during follow-up. Our retrospective study using VVI demonstrates that TC patients also have LV systolic and diastolic longitudinal dysfunction, not just systolic radial dysfunction as assessed by traditional 2D TTE indices. Longitudinal LA dysfunction may also be present.     

Left Atrial Function as Assessed by Speckle-Tracking Echocardiography in Hypertension

We investigated left atrial (LA) function in relation to hypertension using 2-dimensional speckle-tracking echocardiography (STE) in subjects with preserved left ventricular (LV) ejection fraction, while accounting for LA enlargement and LV mass and diastolic function.We performed standard 2-dimensional and Doppler echocardiography and LA volumetric measurements and STE strain imaging in hypertensive patients (systolic/diastolic blood pressure ≥140/90 mmHg, or use of antihypertensive drugs, n = 124) and age- and sex-matched normotensive subjects (n = 124). We measured the peak LA velocity, strain, and strain rate during systole and early and late diastole, respectively. We investigated the associations of interests in the presence or absence of LA enlargement (LA volume index ≥28 mL/m²).Hypertensive and normotensive subjects had similar LV ejection fraction and LA diameter (P ≥ 0.22). However, hypertensive compared with normotensive subjects had enlarged LV and impaired diastolic function, and had increased LA volumetric measurements and decreased LA emptying fractions (P < 0.0001). Hypertensive patients also had impaired LA function, as measured by STE velocity, strain, and strain rate in general and in the absence of LA enlargement (P < 0.0001). The differences in LA STE strain rate during LV systole and LA contraction between hypertension and normotension in the absence of LA enlargement remained statistically significant (P < 0.001), after adjustment for age, sex, and LV mass index and E/E’.Hypertension is associated with impaired LA function, as assessed by STE strain imaging technique, even before LA enlargement develops and after LV remodeling is accounted for.     

Chronic mitral regurgitation: left atrial deformation analysis by two-dimensional speckle tracking echocardiography

Background: Speckle tracking echocardiography (STE) is a novel method for the angle‐independent and objective quantification of myocardial deformation; it has recently evolved, enabling the quantification of longitudinal myocardial left atrial (LA) deformation dynamics. To investigate the effects of chronic mitral regurgitation (MR) on these functional atrial indices, we analyzed LA function by STE in a group of asymptomatic patients with chronic degenerative MR. Methods: The study population included 36 patients with mild MR, 38 with moderate MR, and 42 with severe MR. 52 age‐matched controls were also recruited. Global peak atrial longitudinal strain (global PALS) was measured in all subjects by averaging all atrial segments. Results: Age, gender, and LV ejection fraction in all pathological groups were comparable to those in the controls. Global PALS was higher in the mild MR group (46.7 ± 9.1%) in comparison with the controls (40.5 ± 6.2%; P < 0.001); instead global PALS was lower in the moderate MR group (25.7 ± 7.1%) and further reduced in the severe MR group (13.2 ± 5.2%) in comparison with the controls (40.5 ± 6.2%; overall P < 0.0001 by ANOVA, P < 0.05 for all pairwise comparisons). In multivariate analysis, E/Em ratio emerged as the principal independent determinant of global PALS. Conclusions: Our study provides new insight for the LA function analysis in response to different degrees of MR, showing that STE measurements of LA longitudinal strain may be considered a promising tool for the early detection of impairment of LA compliance in patients with asymptomatic chronic MR. (Echocardiography 2011;28:327‐334)     

Correlation between LV regional strain and LV dyssynchrony assessed by 2D STE in patients with different levels of diastolic dysfunction

Backgrounds: Little is known about left ventricular (LV) circumferential, radial, and longitudinal functions in patients with diastolic dysfunction (DD). The aims of this study were: (1) to characterize circumferential, radial, and longitudinal strain and (2) to use 2D speckle tracking echocardiography (STE) to evaluate LV dyssynchrony in different DD grades. Methods and results: We studied 128 subjects (90 with DD, 38 healthy controls). DD was divided into three groups according to grade (group 1; mild, group 2; moderate, and group 3; severe). Regional strains were measured by 2D STE. Global LV CS was significantly lower in group 3 (-17.4 ± 5.2) compared with healthy controls (-21.2 ± 3.6), group 1 (-20.7 ± 3.9), and group 2 (-20.2 ± 4.0) (P < 0.0001 for each comparison). Global LV RS and LS were significantly lower in all three groups than in controls. Conclusion: LV, LS, and RS were lower in patients with mild to severe DD than in healthy controls. However, LV CS was similar to normal control values in patients with mild to moderate DD but was lower in patients with severe DD. Circumferential segmental LV motion is likely to compensate for impaired longitudinal and radial LV motion in patients with DD. LV dyssynchrony also occurred significantly more frequently in patients with DD with normal EF than in healthy controls. These results suggest that, in patients with DD and normal EF, contraction of the myocardium is not synchronized and that LV dyssynchrony plays a role in producing diastolic heart failure.     

Feasibility of Two‐Dimensional Global Longitudinal Strain and Strain Rate Imaging for the Assessment of Left Atrial Function: A Study in Subjects with a Low Probability of Cardiovascular Disease and Normal Exercise Capacity

Background: Two‐dimensional (2D) speckle imaging has shown that it could evaluate not only regional but also global strain (?) and strain rate (SR) of the left and right ventricles. There are no data for global ?/SR imaging for left atrial (LA) function evaluation. Methods: A total of 54 subjects (37 men; mean age, 44 ± 10 years) with normal treadmill exercise stress echocardiography and no coronary risk factors were enrolled. Global longitudinal LA ?/SR data obtained by 2D speckle imaging with automated software (EchoPAC, GE Medical) were compared with LA volumetric parameters. Results: LA ?/SR imaging was acceptable in all patients. Bland‐Altman analysis for these parameters showed no evidence of any systematic difference regarding inter‐ and intraobserver variabilities. Global longitudinal LA strain during systole and peak systolic global longitudinal LA SR were correlated with LA total emptying fraction (EF) (r = 0.399, P = 0.004; r = 0.366, P = 0.008). Global longitudinal LA strain during early diastole and peak early diastolic global longitudinal LA SR were correlated significantly with LA passive EF (r = 0.476, P < 0.001; r = 0.507, P < 0.001). Global longitudinal LA strain during late diastole and peak late diastolic global longitudinal LA SR were not correlated with LA active EF (r = 0.198, P = 0.163; r = 0.265, P = 0.060). Conclusions: Global longitudinal LA ?/SR parameters determined by 2D speckle tracking echocardiography are feasible and reproducible indices for the evaluation of LA function. (ECHOCARDIOGRAPHY, Volume 26, November 2009)     

Subclinical Left Ventricular Dysfunction in Asymptomatic Severe Aortic Regurgitation Patients with Normal Ejection Fraction: A Combined Tissue Doppler and Velocity Vector Imaging Study

Objectives: Our aim was to evaluate subclinical left ventricular (LV) dysfunction, by two novel echocardiographic techniques, velocity vector imaging (VVI)‐derived strain imaging and tissue Doppler imaging (TDI), in patients with asymptomatic, severe aortic regurgitation (AR). Methods: Forty patients with severe AR with normal ejection fraction and 30 controls were included to the study. All patients underwent a standard echocardiography extended with TDI and VVI analyses. To evaluate the LV longitudinal and circumferential deformation, segmental systolic peak strain and strain rate (SRs) data were acquired from parasternal short axis, apical four‐chamber, two‐chamber, and long axis views, and additionally LV myocardial velocities, isovolumic myocardial acceleration (IVA), peak systolic velocity (Sa) and peak myocardial velocity during isovolumic contraction (IVV) assessed by TDI. Results: IVA was the only TDI‐derived parameter which was significantly impaired in AR patients (P = 0.0001). Both longitudinal and circumferential strain and SRs of the LV were significantly decreased in patients with severe AR (P = 0.0001). Longitudinal and circumferential strain/SRs and TDI‐derived LV IVA were inversely correlated with LV end‐diastolic diameter (P = 0.0001) and end‐systolic diameter (P = 0.0001). TDI‐derived IVA was also very well correlated with longitudinal deformation parameters (P = 0.0001). Conclusions: VVI‐ derived strain imaging and TDI‐derived IVA may be used as adjunctive, reliable, noninvasive parameters for evaluating subclinical ventricular dysfunction in patients with chronic, severe AR. This may help to identify patients for closer follow‐up and to determine the need for surgery before developing irreversible, severe heart failure. (Echocardiography 2010;27:260‐268)