Assessment of Interventricular Dyssynchrony by Real Time Three‐Dimensional Echocardiography: An In Vitro Study in a Porcine Model

Background: Loss of synchronous contraction between or within the right and left ventricle (RV, LV) leads to adverse ventricular function. We used real time three‐dimensional echocardiography (RT3DE) for evaluation of severity of interventricular dyssynchrony and function in a porcine heart model. Methods: Six fresh in vitro porcine hearts were used to create a controlled model of LV and RV dyssynchrony using two sets of pulsatile pumps. Synchronized and dyssynchronized pump settings were used with two different dyssynchronized settings: LV filled first and RV filled first. Results: There was good correlation between actual measurement and RT3DE for interventricular time difference (r = 0.95, P < 0.0001) and stroke volume (SV) for LV and RV (0.89, 0.85; P < 0.0001, respectively). RT3DE data showed a small but significant underestimation for actual volume (P < 0.05). The intra‐ and interobserver variabilities are 2.9 ± 1.5% and 3.1 ± 5.4% for LV and RV SVs, and 1.7 ± 2.4% and 2.2 ± 3.2% for time differences by RT3DE. There was significant difference in RV SV between synchrony and dyssynchrony when the RV filled first (P < 0.05), but not in other groups. The same pattern was found in RT3DE derived SVs (synchrony versus dyssynchrony with RV filled first, P < 0.05). Conclusions: There is no compromise in LV SV during interventricular dyssynchrony; but RV SV was significantly diminished when the RV filled first. RT3DE is a feasible, robust and reproducible method to identify interventricular dyssynchrony and to evaluate ventricular SVs. (Echocardiography 2010;27:709‐715)     

Diagnosing diastolic heart failure

BACKGROUND: increasing evidence supports the existence of left ventricular diastolic dysfunction as an important cause of congestive heart failure, present in up to 40% of heart failure patients. AIM: to review the pathophysiology of LV diastolic dysfunction and diastolic heart failure and the currently available methods to diagnose these disorders. RESULTS: for diagnosing LV diastolic dysfunction, invasive hemodynamic measurements are the gold standard. Additional exercise testing with assessment of LV volumes and pressures may be of help in detecting exercise-induced elevation of filling pressures because of diastolic dysfunction. However, echocardiography is obtained more easily, and will remain the most often used method for diagnosing diastolic heart failure in the coming years. MRI may provide noninvasive determination of LV three-dimensional motion during diastole, but data on correlation of MRI data with clinical findings are scant, and possibilities for widespread application are limited at this moment. CONCLUSIONS: in the forthcoming years, optimal diagnostic and therapeutic strategies for patients with primary diastolic heart failure have to be developed. Therefore, future heart failure trials should incorporate patients with diastolic heart failure, describing precise details of LV systolic and diastolic function in their study populations.     

超声心动图评价左心室功能的研究进展

左室功能的准确测定对临床诊断和治疗有着重要意义,超声心动图是目前最常用于测量左室功能的工具,其具有无创、廉价、重复性好等优点,更为重要的是它不仅可用于评价左室整体收缩功能,还能更加完善地评价左室舒张功能和局部心肌运动,现对近年来超声心动图评价上述心功能的主要方法进行回顾。     

Relationship of Cardiac Hypertrophy and Diastolic Dysfunction Assessed by Echocardiography with Atherosclerosis in Retinal Arteries in Hypertensive Patients

Although left ventricular (LV) hypertrophy and diastolic dysfunction assessed by echocardiography are established risk markers of cardiovascular events in hypertensive patients, relationships between these echocardiographic findings and atherosclerosis have not been fully elucidated. The purpose of this study was to examine the relationships between atherosclerosis of the retinal arteries and echocardiographic findings in hypertensive patients. Forty hypertensive patients were divided into two groups according to Scheie's classification by ophthalmologists: 20 patients with stage 1 changes (visible broadening of the light reflex from the artery with minimal arteriovenous compression) and 20 patients with stage 2 changes (more prominent than those in stage 1). Standard echocardiography was performed to measure LV mass index for evaluating LV hypertrophy and conventional diastolic transmitral flow velocities for assessing LV diastolic function. Mitral annular velocities were also measured for evaluating LV diastolic function using tissue Doppler echocardiography. The LV mass index was larger in stage 2 (130 ± 39 g/m²) than stage 1 (96 ± 16 g/m²) patients (p?=?0.001). Peak early diastolic mitral annular velocity (E′) was lower in stage 2 (5.9 ± 0.9 cm/s) than stage 1 (7.9 ± 1.7 cm/s) patients (p?=?0.001). The optimal cutoff points for the diagnosis of Scheie stage 2 were 6.6 cm/sec for E′ (sensitivity 75%, specificity 85%) and 111 g/m² for LV mass index (sensitivity 70%, specificity 90%). In conclusion, in hypertensive patients, the extent of atherosclerosis in the retinal arteries can be estimated by LV hypertrophy and diastolic dysfunction assessed by echocardiography.     

Altered Early Left Ventricular Diastolic Wall Velocities in Pulmonary Hypertension: A Tissue Doppler Study

Background: Left ventricular diastolic dysfunction (LVDD) is known to occur in severe chronic pulmonary hypertension (PH); however, the mechanism(s) remains unclear. Methods: Tissue Doppler imaging (TDI) was used to track early (E) diastolic signals of basal and mid portions of the interventricular septum (IS) and LV free wall (LVFw) in 20 patients (60 ± 8 years) with documented LVDD without PH and in 30 patients (60 ± 11 years) with known chronic PH. All subjects were in normal sinus rhythm and had normal LV ejection fraction. Results: PH patients had lower early (E) wave velocities in basal IS (–4.2 ± 1.9 vs. –5.9 ± 1.2 cm/sec; P < 0.001), distal IS (–2.6 ± 2.6 vs. –4.2 ± 1.1 cm/sec; P < 0.01), and basal LVFw (–5.2 ± 1.7 vs. –6.5 ± 1.2 cm/sec; P < 0.01) than patients with LVDD and no PH. Finally, worsening PH distorts the entire IS diastolic tracing resulting in asynchronous diastolic signals. Conclusions: The presence of PH not only decreases IS early (E) wave diastolic velocity generation but also distorts the entire pattern of IS diastolic relaxation when compared to patients with typical LVDD and no PH. Further studies are now needed to assess the full effect of PH on LV diastole and how this influences clinical outcomes. (ECHOCARDIOGRAPHY, Volume 26, November 2009)     

彩色M型多普勒超声评价高血压病人的左室舒张功能

目的 应用彩色M型多普勒超声心动图测量舒张早期左室内血流传播速度(vp)，评价高血压病人的左室舒张功能。方法 高血压组195例(50岁以下者23例；50—70岁者101例；70岁以上者71例)。正常对照组136例(如岁以下者53例；50—70岁者50例；70岁以上者33例)。取心尖四腔或二腔心平面测量左室内血流传播速度(Vp)，二尖瓣和肺静脉血流曲线。结果 高血压病人的Vp值较正常人降低(P＜0．01)，血流形态异常。结论 应用彩色M型多普勒超声心动图测量舒张早期左室内血流传播速度，不受心脏负荷及年龄的影响，作为评价高血压病人左室舒张功能的指标有临床意义。     

Reference Techniques for Left Ventricular Volume Measurement by Three-Dimensional Echocardiography: Determination of Precision, Accuracy, and Feasibility

The use of multiple in vitro reference methods to validate three-dimensional (3-D) echocardiographic techniques makes comparison difficult. In an attempt to establish a reference standard, we studied precision, accuracy, and feasibility of a true left ventricular (LV) volume measurement in six dog heart specimens using three techniques, called fluid, sheath, and cast. LV volumes ranged from 30 to 105 mL. Intraobserver variability was minimal in all combinations (1.26% to 2.8%) with a statistically insignificant tendency to higher values in the cast method. The cast method, however, exhibited significantly higher interobserver variability (5.78%) as compared to that ranging from 1.47% to 1.59% in the remaining two techniques. Regression analysis demonstrated high correlations among the three techniques assessed by 95% confidence limits and correlation coefficient (R² > 0.98, P < 0.01). Mean differences among the techniques (0.12 to 1.08 mL) were not significant. The fluid technique was easy to perform. The sheath technique required some practice. The cast method was sensitive to accurate preparation of a gelatin mixture. We conclude that the fluid and sheath techniques are precise, accurate, and feasible. We recommend their use as reference standards in laboratory LV volume measurement. Validation 3-D echocardiographic studies using either of these two techniques will be comparable. Although the accuracy of the cast technique is excellent, its lower precision makes it a second choice. It could be used in cases where an LV cavity cast is required and higher interobserver variability is acceptable.     

Safety and Feasibility of Real Time Adenosine Myocardial Contrast Echocardiography with Emphasis on Induction of Arrhythmias: A Study in Healthy Volunteers and Patients with Stable Coronary Artery Disease

Introduction: Some studies reported an increased incidence of premature ventricular complexes (PVCs) during triggered myocardial contrast echocardiography (MCE) using high-intensity ultrasound destruction. Whether PVCs are also induced by real time MCE using low emission power, is unknown. The aim of the study was to assess the occurrence of arrhythmias during real time adenosine MCE in healthy volunteers and patients with stable coronary artery disease (CAD). Methods: Fifty healthy volunteers and 26 patients with stable CAD underwent real time MCE using Sonovue and power pulse inversion (ATL 5000) at rest and during adenosine stress. The occurrence of premature atrial complexes (PAC) and PVCs was analyzed before and during MCE using ECG-tracings from videotapes. Results: In healthy subjects, the occurrence of PVCs at baseline (0.04 ± 0.23 PVCs/min) was similar at rest (0.04 ± 0.23 PVCs/min, P = NS), and adenosine stress (0.03 ± 0.14, P = NS). In CAD patients, the occurrence of PVCs at baseline was 0.30 ± 0.76 PVC/min, compared to 0.29 ± 0.74 at rest (P = NS), and 0.34 ± 0.74 during adenosine stress (P = NS). The number of subjects demonstrating PVCs did not increase during MCE. The occurrence of PACs during MCE was not increased compared to baseline. Conclusion: Real time MCE using low emission power does not increase the occurrence of premature complexes in healthy volunteers or CAD patients.     

Saline Contrast Echocardiography for the Detection of Patent Foramen Ovale in Hypoxia: A Validation Study Using Intracardiac Echocardiography

Although the “3 beat rule” is widely utiized to discriminate patent foramen ovale (PFO)‐mediated right‐to‐left shunt (RTLS) from intrapulmonary RTLS using saline contrast transthoracic echocardiography (SCE), SCE diagnostic performance has yet to be validated using an invasive intracardiac standard. Percutaneous PFO occluder placement was recently shown to ameliorate hypoxia in patients with suspected PFO‐mediated RTLS. We evaluated the ability of SCE to predict PFO presence and size using intracardiac echocardiography (ICE) as a gold standard in a hypoxic cohort. Sixty‐three hypoxic patients with suspected PFO‐mediated RTLS who underwent SCE at rest, with Valsalva maneuver, and with cough prior to ICE were evaluated retrospectively. PFO RTLS was defined by ICE findings including PFO anatomy, RTLS by saline contrast and color Doppler, and probe patency. SCE shunt severity and timing of left heart saline target appearance were compared to the presence of ICE‐defined PFO RTLS. Forty‐seven patients (75%) met criteria for PFO‐mediated RTLS. A 4 beat cutoff for resting SCE provided optimal diagnostic performance for detection of PFO‐mediated RTLS with a 71% sensitivity, 94% specificity, and 97% positive predictive value (PPV). Valsalva and cough maneuvers improved sensitivity compared to rest SCE (89% and 80%, respectively). Valsalva SCE shunt severity more accurately predicted PFO size than resting SCE. In contrast to the widely accepted “3 beat rule,” resting SCE for the detection of PFO RTLS in a hypoxic population performs optimally using a 4‐cycle cutoff with both excellent specificity and PPV.     

Heart failure after myocardial infarction: the importance of diastolic dysfunction: A prospective clinical and echocardiographic study

Clinical signs of heart failure based on predefined criteriawere analysed in 217 survivors (<75 years of age) of an acutemyocardial infarction (AMI). A Doppler investigation and M-modeechocardiography were performed 3–5 days after the indexinfarction. All patients were stratified according to left ventricularend-diastolic diameter 28 mm. m^–2 body surface area. Fractionalshortening, E-point septal separation, Keren's echo-index basedon left ventricular end-diastolic diameter, fractional shorteningand E-point septal separation were used as indices of systolicfunction, and the EI A ratio and isovolumic relaxation timeas indices of diastolic function. Fifty-one per cent of thepatients (n=111) had heart failure. Left ventricular end-diastolicdiameter was <28 mm. m^–2 body surface area in 32 (29%)of the heart failure patients and in 44 (45%) of those withoutheart failure. An abnormal Keren's echo-index was found in 58(52%) of the heart failure patients compared with 17 (18%) withoutheart failure. The EIA ratio was lower (0.65 vs 0.77, P=0.01)in heart failure patients with a normal left ventricular end-diastolicdiameter compared with patients without heart failure and anormal left ventricular end-diastolic diameter. Infarct size,E-point septal separation, heart rate and age were determinantsof heart failure in multivariate analyses with all patientsincluded. Infarct size and the EI A ratio were determinantsof heart failure in patients with a normal left ventricularend-diastolic diameter. Systolic dysfunction is a determinant of heart failure in themajority of patients after AMI, whereas diastolic dysfunctionis a determinant of heart failure in patients with a normalleft ventricular end-diastolic diameter. Abnormal findings regardingleft ventricular diameter and systolic function are presentin 55% and 18%, respectively, of the patients without heartfailure.     

Diagnosis of Ventricular Aneurysm and Other Severe Segmental Left Ventricular Dysfunction Consequent to a Myocardial Infarction in the Presence of Right Bundle Branch Block: ECG Correlates of a Positive Diagnosis Made via Echocardiography and/or Contrast Ventriculography

Background: A diagnostic ECG sign of a ventricular aneurysm (VA) consequent to a myocardial infarction (MI) in the presence of complete left bundle branch block was recently described, and consists of the presence of ST‐segment elevation (+ST), instead of the expected ST‐segment depression (?ST), in leads V_4–6. Generally, complete right bundle branch block (RBBB) is associated with ?ST in ECG leads V_1–3. We hypothesized that stable +ST, instead of the expected ?ST in leads V_1–3 in patients with RBBB could be also diagnostic of a VA and other severe segmental left ventricular dysfunction (VA/SSD). Thus, this study was performed to explore the feasibility of using the ECG to diagnose a VA/SSD in the presence of RBBB, and to evaluate the determinants of such diagnosis. Methods: The frequency of +ST ≥1 mm in leads V_1–3 was assessed in patients with RBBB, prior MI, and a VA/SSD diagnosed by echocardiography and/or contrast left cine‐ventriculography. The ECG correlates for a positive or negative diagnosis of a VA/SSD were explored. Results: Out of 4197 files of our cohort of the Cardiology Clinic, RBBB was detected in 175 patients. Of these, 28 had an old MI, and had a VA/SSD diagnosed by ≥1 of noninvasive and/or invasive non‐ECG tests. Twenty‐one of these 28 patients had stable +ST in ≥1 of leads V_1–3 (Group 1), and 7 did not (Group 2). Thus, the sensitivity of this ECG criterion for the diagnosis of VA/SSD was 75%, and the specificity was 100% in this highly selective group. VA/SSD in the septal and anterior myocardial regions was more frequent in the patients of Group 1, than in the patients of Group 2 (P = 0.03 and 0.02, correspondingly). The number of myocardial territories involved with the VA/SSD, or the ejection fraction were not different in the two groups (P = 0.65 and 0.55, correspondingly). Conclusion: VA/SSD can be diagnosed in the presence of RBBB by the concordant to the QRS repolarization changes (+ST) in leads V_1–3. Positivity of this ECG marker for VA/SSD correlates with involvement of the septal or anterior myocardial regions, and represents mechanistically a superimposition of primary repolarization alterations, overcoming the secondary such changes.     

Echocardiographic evaluation of left ventricular end diastolic pressure in patients with diastolic heart failure: A comparative study with real-time catheterization

To evaluate the left ventricular end diastolic pressure (LVEDP) in patients with diastolic heart failure by echocardiography and explore the clinical value of echocardiography.From July 2017 to January 2018, 120 patients were prospectively selected from the affiliated hospital of Jiangsu university diagnosed as diastolic heart failure (York Heart Association class ≥II, LVEF ≥50%). The patients were divided into group with LVEDP ≤15 mm hg (1 mm hg = 0.133 kpa) (43 cases) and the group with LVEDP >15 mm hg (77 cases) according to the real-time measurement of LVEDP. Receiver operator characteristic curves of each parameter of echocardiography in diagnosis of LVEDP were compared between the 2 groups.Common ultrasonic parameters such as left ventricular inflow tract blood flow propagation velocity, mitral valve diastole e peak velocity/mitral valve diastole a peak velocity, e peak deceleration time, a peak duration, and early diastole interventricular septum bicuspid annulus velocity e’ (e''sep) were used to evaluate LVEDP elevation with low accuracy (AUC is only between 0.5 and 0.7). Other ultrasonic parameters such as left atrial volume index (LAVI), tricuspid regurgitation maximum flow rate (TRmax), early diastole left ventricular sidewall bicuspid annulus velocity e’ (e’lat), average e’, E/e''sep, E/e’lat, average E/e’ were used to evaluate LVEDP elevation with a certain improvement in accuracy (AUC between 0.7 and 0.9). Propagation velocity, mitral valve diastole e peak velocity/mitral valve diastole a peak velocity, e peak deceleration time, a peak duration, e''sep, average e’, E/e''sep have very low correlation with LVEDP (r = −0.283 to 0.281); LAVI, TRmax, e’lat, E/e’lat, average E/e’ and LVEDP are not highly correlated (r = 0.330–0.478). Through real-time left ventricular manometry, multiple regression analysis showed that TRmax, average e’, e’lat, LAVI were independently correlated with the actual measured LVEDP.Echocardiography can recognize the increase of LVEDP in patients with heart failure preserved by LVEF, and estimate the value of LVEDP roughly, which can reflect LVEDP to a certain extent, with high feasibility and accuracy.     

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。     

Real Time Three‐Dimensional Echocardiography for Quantification of Ventricular Volumes,Mass, and Function in Children with Congenital and Acquired Heart Diseases

Quantitative measurement of left ventricular (LV) volumes, mass, and function is one of the most common and important indications for echocardiography. These measurements are among the most powerful tools for diagnosis and prognosis of congenital and acquired heart diseases and for assessment of medical, percutaneous, and surgical interventions. Awareness is also growing of the importance of right ventricular (RV) volume, mass, and function in many cardiopulmonary diseases. Furthermore, there are challenges and opportunities to measure the volume, mass, and function of complex chambers such as the left atrium, right atrium, and the univentricular heart. As echocardiography continues to be the imaging modality of choice for these measurements, the strengths and limitations of M‐mode, two‐dimensional (2D), and recently three‐dimensional (3D) echocardiographic (3DE) methodologies for accurate and reproducible measurement of these indices have been extensively investigated for congenital and acquired heart diseases. Evidence suggests that 3DE provides improved accuracy and reproducibility over 2D methods for measurement of LV volume and function calculation in adults and in children. Data have accumulated on the utility of 3DE for measuring chamber volumes and function for the RV and for the single ventricle, which may become more widely used in clinical and research arenas in the future. Finally, new advanced modes of analysis such as 3D strain and synchrony analysis by 3DE are promising methodologies that warrant further investigation.