Jing Ping Sun

Myocardial Strain Measurement With 2-Dimensional Speckle-Tracking Echocardiography: Definition of Normal Range

The interpretation of wall motion is an important component of echocardiography but remains a source of variation between observers. It has been believed that automated quantification of left ventricular (LV) systolic function by measurement of LV systolic strain from speckle-tracking echocardiography might be helpful. This multicenter study of nearly 250 volunteers without evidence of cardiovascular disease showed an average LV peak systolic strain of -18.6 +/- 0.1%. Although strain was influenced by weight, blood pressure, and heart rate, these features accounted for only 16% of variance. However, there was significant segmental variation of regional strain to necessitate the use of site-specific normal ranges.

Clinical and Echocardiographic Characteristics of Papillary Fibroelastomas A Retrospective and Prospective Study in 162 Patients

Background—Cardiac papillary fibroelastoma (CPF) is a primary cardiac neoplasm that is increasingly detected by echocardiography. The clinical manifestations of this entity are not well described. Methods and Results—In a 16-year period, we identified patients with CPF from our pathology and echocardiography databases. A total of 162 patients had pathologically confirmed CPF. Echocardiography was performed in 141 patients with 158 CPFs, and 48 patients had CPFs that were not visible by echocardiography (<0.2 cm), leaving an echocardiographic subgroup of 93 patients with 110 CPFs. An additional 45 patients with a presumed diagnosis of CPF were identified. The mean age of the patients was 60±16 years of age, and 46.1% were male. Echocardiographically, the mean size of the CPFs was 9±4.6 mm; 82.7% occurred on valves (aortic more than mitral), 43.6% were mobile, and 91.4% were single. During a follow-up period of 11±22 months, 23 of 26 patients with a prospective diagnosis of CPF that was confirmed by pathological examination had symptoms that could be attributable to embolization. In the group of 45 patients with a presumed diagnosis of CPF, 3 patients had symptoms that were likely due to embolization (incidence, 6.6%) during a follow-up period of 552±706 days. Conclusions—CPFs are generally small and single, occur most often on valvular surfaces, and may be mobile, resulting in embolization. Because of the potential for embolic events, symptomatic patients, patients undergoing cardiac surgery for other lesions, and those with highly mobile and large CPFs should be considered for surgical excision.

Validation of real-time three-dimensional echocardiography for quantifying left ventricular volumes in the presence of a left ventricular aneurysm: in vitro and in vivo studies

OBJECTIVESnTo validate the accuracy of real-time three-dimensional echocardiography (RT3DE) for quantifying aneurysmal left ventricular (LV) volumes.nnnBACKGROUNDnConventional two-dimensional echocardiography (2DE) has limitations when applied for quantification of LV volumes in patients with LV aneurysms.nnnMETHODSnSeven aneurysmal balloons, 15 sheep (5 with chronic LV aneurysms and 10 without LV aneurysms) during 60 different hemodynamic conditions and 29 patients (13 with chronic LV aneurysms and 16 with normal LV) underwent RT3DE and 2DE. Electromagnetic flow meters and magnetic resonance imaging (MRI) served as reference standards in the animals and in the patients, respectively. Rotated apical six-plane method with multiplanar Simpsons rule and apical biplane Simpsons rule were used to determine LV volumes by RT3DE and 2DE, respectively.nnnRESULTSnBoth RT3DE and 2DE correlated well with actual volumes for aneurysmal balloons. However, a significantly smaller mean difference (MD) was found between RT3DE and actual volumes (-7 ml for RT3DE vs. 22 ml for 2DE, p = 0.0002). Excellent correlation and agreement between RT3DE and electromagnetic flow meters for LV stroke volumes for animals with aneurysms were observed, while 2DE showed lesser correlation and agreement (r = 0.97, MD = -1.0 ml vs. r = 0.76, MD = 4.4 ml). In patients with LV aneurysms, better correlation and agreement between RT3DE and MRI for LV volumes were obtained (r = 0.99, MD = -28 ml) than between 2DE and MRI (r = 0.91, MD = -49 ml).nnnCONCLUSIONSnFor geometrically asymmetric LVs associated with ventricular aneurysms, RT3DE can accurately quantify LV volumes.

Comparison of Mortality Rates and Progression of Left Ventricular Dysfunction in Patients With Idiopathic Dilated Cardiomyopathy and Dilated Versus Nondilated Right Ventricular Cavities

This study assesses the influence of right ventricular (RV) dilation on the progression of left ventricular (LV) dysfunction and survival in patients with idiopathic dilated cardiomyopathy (IDC). Using transthoracic echocardiography, we studied 100 patients with IDC aged 20 to 80 years (mean 55 +/- 14); 67% were men. In the apical 4-chamber view, diastolic LV and RV chamber area measurements classified patients into 2 groups: group RV enlargement+ (RV area/LV area > 0.5) included 54 patients; group RV enlargement- (no RV enlargement) had RV area/LV area < or = 0.5. Echocardiographic studies were repeated in all patients after a mean of 33 +/- 16 months. At the time of the initial study, the 2 groups did not differ in age, gender, incidence of atrial fibrillation and diabetes, left ventricular mass, and LV ejection fraction, but the RV enlargement+ group had more severe tricuspid regurgitation and less LV enlargement. After 47 +/- 22 months (range 12 to 96), patients in group RV enlargement+ had lower LV ejection fraction (29% vs 34%, p = 0.006) than patients with initial RV enlargement-. At clinical follow-up, mortality was higher (43%) in patients with initial RV enlargement+ than the RV enlargement- patients (15%), p = 0.002. For survivors, the mitral deceleration time averaged 157 +/- 36 ms; for nonsurvivors or patients who required transplant, the mitral deceleration time averaged 97 +/- 12 ms (p < 0.0001). With use of a multivariate Cox model adjusting for LV ejection fraction, LV size, and age, the relative risk ratio of mortality from initial RV enlargement+ was 4.4 (95% confidence limits 1.7 to 11.1) (p = 0.002). Thus, patients with significant RV dilation had nearly triple the mortality over 4 years and more rapidly deteriorating LV function than patients with less initial RV dilation. In IDC, RV enlargement is a strong marker for adverse prognosis that may represent a different morphologic subset.

Automated Cardiac Output Measurement by Spatiotemporal Integration of Color Doppler Data In Vitro and Clinical Validation

BACKGROUNDnA new Doppler echocardiographic technique has been developed for automated cardiac output measurement (ACOM) that assumes neither a flat flow profile nor collinearity with the scan line, but clinical validation of this method is lacking.nnnMETHODS AND RESULTSnIn 165 subjects (50 intensive care patients, 10 dobutamine echocardiography patients, and 105 normal volunteers; age, 49.4 +/- 19.3 years; 92 men), ACOM was performed in the left ventricular outflow tract (LVOT), with the color baseline shifted to avoid aliasing. ACOM was also tested in a pulsatile in vitro model. Stroke volume was calculated by double integration of Doppler signals in space (across the LVOT) and in time (through the systolic period), assuming hemiaxial symmetry: integral of integral of pi r v(r,t) dr dt, where v(r,t) is the velocity at a distance r from the center of the LVOT at time t during systole. Stroke volume from ACOM was compared with thermodilution (TD), aortic valve pulsed-wave Doppler (PWAO), and left ventricular echocardiographic (two-dimensional [2D]) methods. There was good correlation between ACOM and PWAO (r = .93). TD (r = .86), and 2D (r = .74), with close agreement seen. ACOM had higher correlation and agreement with TD than did either PWAO (P < .02) or 2D (P < .01). ACOM was also able to track accurately the changes in cardiac output with dobutamine infusion in comparison with PWAO (r = .94). In vitro assessment demonstrated excellent correlation (r = .98, y = 1.0x + 1.94) with little impact of pulse repetition frequency or misalignment up to 30 degrees. Gain dependency was noted but could be optimized by visual inspection of the color image.nnnCONCLUSIONSnAutomatic integration of numerical data within color Doppler flow fields is a feasible new method for quantifying flow. It is simpler and faster, requires fewer assumptions, and uses only one apical view. ACOM is a promising new approach to echocardiographic quantification that deserves further study and refinement.

Noninvasive Assessment of Cardiac Resynchronization Therapy for Congestive Heart Failure Using Myocardial Strain and Left Ventricular Peak Power as Parameters of Myocardial Synchrony and Function

Resynchronization Therapy for Heart Failure. Introduction: Although invasive studies have shown that cardiac resynchronization therapy by biventricular pacing improves left ventricular (LV) function in selected heart failure patients, it is impractical to apply such techniques in the clinical setting. The aim of this study was to assess the acute effects of cardiac resynchronization therapy by noninvasive techniques.

Differences in left ventricular long‐axis function from mice to humans follow allometric scaling to ventricular size

While the heart size maintains a constant proportion to body size, heart function parameters, such as heart rate and cardiac output, show a more complex scaling pattern. How these phenomena affect the long‐axis left ventricular (LV) function is unknown. We studied 10 mice, 15 rats, 6 rabbits, 8 mongrel dogs and 38 human volunteers. Doppler tissue echocardiography data were postprocessed to reconstruct mitral annulus (MA) peak systolic velocity and displacement. The relationship between MA peak velocity, MA displacement and LV ejection time, and LV end‐diastolic volume (and mass) were fit to an allometric (power‐law) equation Y=kMβ. LV mass varied from 0.062 to 255 g, while end‐diastolic volume varied from 0.014 to 205 ml. β values of the relation between LV ejection time and LV end‐diastolic volume and mass were 0.247 ± 0.017 and 0.267 ± 0.018, respectively. β values of the relationship between MA displacement and LV end‐diastolic volume and mass were 0.358 ± 0.047 and 0.390 ± 0.051 (P < 0.023 versusβ of LV ejection time). β values of the relationship between MA peak systolic velocity and LV end‐diastolic volume and mass were 0.096 ± 0.012 and 0.100 ± 0.013, respectively (P < 0.0001 versus 0). Finally, β values of the relationship between the long‐to‐short axis displacement ratio and LV end‐diastolic volume and mass were 0.077 ± 0.017 and 0.086 ± 0.019 (P < 0.0001 versus 0). We conclude that MA velocity, displacement, and long‐to‐short axis displacement ratio scale allometrically to heart size. This reduces the relative long‐axis contribution to heart function in small mammals.

Left atrial regional phasic strain, strain rate and velocity by speckle-tracking echocardiography: Normal values and effects of aging in a large group of normal subjects

BACKGROUNDnTwo-dimensional (2D) speckle tracking echocardiography (STE) is a new tool for evaluation of LA function. The aims of this study are to establish the normal range of LA function measured by 2DSTE in different age groups and to evaluate the relations between the parameters of 2DSTE and Doppler echocardiography in evaluating LA and LV diastolic function in healthy adults.nnnMETHODSnA total of 121 healthy volunteers (62 males, aged 47±15) were studied. The LA STE curves were obtained using R-wave onset of the electrocardiogram as a reference point. The LA strain during systolic, early and late diastole (εs, εa and εe = εr - εa); strain rate (SRs, SR, SRe and SRa); velocity (Vs, Ve and Va) were analyzed by commercialized software (EchoPAC). The differences between these parameters were analyzed in different age groups (≤35, 36-55 and ≥55 years) in both genders and compared with the corresponding Doppler echocardiographic indices.nnnRESULTSnGlobal LA εs, εe, and εa were 46.8±7.7, 27.3±6.4 and 19.6±4.2%; SRs, SRe, and SRa were 2.4±0.5, -2.4±0.7 and -2.8±0.6 1/s; Vs, Ve and Va were -5.3±0.9, 5.8±1.2 and 5.2±1.1cm/s respectively. The global LA 2DSTE parameters significantly correlated with Doppler echocardiographic indices which represented LA or LV diastolic function. Moreover, the STE LA parameters correlated significantly with age but not gender.nnnCONCLUSIONSnThis study provides the normal range of LA strain, strain rate and velocity in 3 age groups, which are closely correlated with LA and LV function. The detailed assessment of LA phasic mechanics by 2DSTE may prove to be an important tool for future clinical studies.

Feasibility of single-beat full-volume capture real-time three-dimensional echocardiography for quantification of right ventricular volume: Validation by cardiac magnetic resonance imaging

BACKGROUNDnThe lack of an accurate noninvasive method for assessing right ventricular (RV) volume and function has been a major deficiency of two-dimensional (2D) echocardiography. The aim of our study was to test the feasibility of single-beat full-volume capture with real-time three-dimensional echo (3DE) imaging system for the evaluation of RV volumes and function validated by cardiac magnetic resonance imaging (CMRI).nnnMETHODSnSixty-one subjects (16 normal subjects, 20 patients with hypertension, 16 patients with pulmonary heart disease and 9 patients with coronary heart disease) were studied. RV volume and function assessments using 3DE were compared with manual tracing with CMRI as the reference method.nnnRESULTSnFifty-nine of 61 patients (96.7%; 36 male, mean age, 62 ± 15 years) had adequate three-dimensional echocardiographic data sets for analysis. The mean RV end diastolic volume (EDV) was 105 ± 38 ml, end-systolic volume (ESV) was 60 ± 30 and RV ejection fraction (EF) was 44 ± 11% by CMRI; and EDV 103 ± 38 ml, ESV 60 ± 28 ml and RV EF 41 ± 13% by 3DE. The correlations and agreements between measurements estimated by two methods were acceptable.nnnCONCLUSIONnRV volumes and function can be analyzed with 3DE software in most of subjects with or without heart diseases, which is able to be estimated with single-beat full-volume capture with real-time 3DE compared with CMRI.

Diagnosis of patent foramen ovale by contrast versus color Doppler by transesophageal echocardiography: Relation to atrial size

To ascertain the factors related to the transesophageal echocardiographic diagnosis of patent foramen ovale, the primary echocardiographic data were reviewed from 74 patients with that diagnosis. Similar detection rates were observed with contrast echocardiography (82%) and color flow mapping (78%), but contrast was more sensitive in patients with normal-sized atria (94%) and isolated right atrial enlargement (100%) than in those with enlarged left atria, all but three of whom had biatrial enlargement (52%) (p < 0.001 by chi-square test). Doppler flow mapping was less sensitive for normal-sized atria (66%) than for isolated enlarged right atria (81%) and left (bi-) atrial enlargement (96%) (p = 0.024). Patent foramen ovale was directly visualized by two-dimensional echocardiography in 80%, with close agreement to the size of the color flow jet (r = 0.90, delta = 0.1 +/- 0.4 mm); foramen ovale size was related to right atrial area (r = 0.31, p = 0.015). Thus both saline contrast and color flow imaging are necessary to exclude the diagnosis of patent foramen ovale.