Intrauterine growth restriction impairs right ventricular response to hypoxia in adult male rats.

BACKGROUND: Intrauterine growth restriction (IUGR) predisposes to cardiovascular diseases in adulthood. The mechanisms of this phenomenon remain cryptic. We hypothesized that heart mitochondria in IUGR-born adult rats are more sensitive to acute hypoxia which translates into dysfunctional cardiac response to hypoxic stress. METHODS: Adult IUGR-born male rats (the offspring of dams fed with calories-restricted diet during pregnancy) were exposed to acute hypoxic stress with echocardiographic assessment of cardiac function. In parallel, mitochondrial respiration in organelles isolated from left ventricle (LV) and right ventricle (RV) was tested in normoxic and anoxic conditions. The extent of post-anoxic inhibition of mitochondrial respiration and cardiac function was compared with controls, non-IUGR rats. RESULTS: Compared with controls, in the IUGR rats hypoxia significantly reduced only RV contractility, evidenced by decreased fractional shortening, functional area of contraction, and tricuspid annular plane systolic excursion. In isolated mitochondria, anoxic challenge inhibited respiratory chain in both groups of rats. However, compared with controls, the extent of anoxic mitochondrial depression was significantly greater in IUGR-born rats, but only in the organelles isolated from RV. CONCLUSIONS: In adult IUGR-born rats, mitochondria from RV are hypersensitive to oxygen deprivation and this translates into maladaptive RV cardiac response to acute hypoxia.

Three-Dimensional Speckle Tracking Imaging for Assessing Left Atrial Function in Hypertensive Patients With Paroxysmal Atrial Fibrillation.

Hypertension (HT) is known to be the most prevalent risk factor for paroxysmal atrial fibrillation (PAF), however, its mechanisms have not been fully clarified. Our aim was to investigate the differences in left atrial (LA) function between healthy subjects, and hypertensive patients without PAF (HT-PAF(-)) and with PAF (HT-PAF(+)) using 3-dimensional (3D) speckle tracking imaging (STI). A total of 144 subjects were enrolled: 44 HT-PAF(+) (27 males; mean age 69 ± 10 years), 50 HT-PAF(-) (31 males; mean age 63 ± 11 years), and 50 controls (31 males; mean age 51 ± 14 years). All subjects were in sinus rhythm during the examination. LA volume, LA emptying fraction (LAEF), and LA wall strain were analyzed by 3D area tracking imaging. The maximal value of the global strain curve was defined as the peak global strain. The standard deviation of the time from the R-wave on the electrocardiogram to peak positive values of the segmental strain curves corrected by the R-R' interval in 6 mid LA segments (TP-SD) was calculated to assess LA dyssynchrony. LAEF and peak global strain were lower in HT-PAF(+) than in HT-PAF(-) (P < 0.01) and in the control (P < 0.01). Moreover, TP-SD was higher in HT-PAF(+) than in HT-PAF(-) (P < 0.05) and in the control (P < 0.01). Multivariate analysis revealed LA volume index, peak global strain, and TP-SD were independent determinants of HT-PAF(+). The presence of PAF is associated with diminished LA compliance and advanced mechanical dyssynchrony, as well as LA geometric deformation.

Chronic ethanol consumption increases cardiomyocyte fatty acid uptake and decreases ventricular contractile function in C57BL/6J mice.

Alcohol, a major cause of human cardiomyopathy, decreases cardiac contractility in both animals and man. However, key features of alcohol-related human heart disease are not consistently reproduced in animal models. Accordingly, we studied cardiac histology, contractile function, cardiomyocyte long chain fatty acid (LCFA) uptake, and gene expression in male C57BL/6J mice consuming 0, 10, 14, or 18% ethanol in drinking water for 3months. At sacrifice, all EtOH groups had mildly decreased body and increased heart weights, dose-dependent increases in cardiac triglycerides and a marked increase in cardiac fatty acid ethyl esters. [(3)H]-oleic acid uptake kinetics demonstrated increased facilitated cardiomyocyte LCFA uptake, associated with increased expression of genes encoding the LCFA transporters CD36 and Slc27a1 (FATP1) in EtOH-fed animals. Although SCD-1 expression was increased, lipidomic analysis did not indicate significantly increased de novo LCFA synthesis. By echocardiography, ejection fraction (EF) and the related fractional shortening (FS) of left ventricular diameter during systole were reduced and negatively correlated with cardiac triglycerides. Expression of myocardial PGC-1α and multiple downstream target genes in the oxidative phosphorylation pathway, including several in the electron transport and ATP synthase complexes of the inner mitochondrial membrane, were down-regulated. Cardiac ATP was correspondingly reduced. The data suggest that decreased expression of PGC-1α and its target genes result in decreased cardiac ATP levels, which may explain the decrease in myocardial contractile function caused by chronic EtOH intake. This model recapitulates important features of human alcoholic cardiomyopathy and illustrates a potentially important pathophysiologic link between cardiac lipid metabolism and function.

Diagnostic accuracy of transthoracic and transesophageal echocardiography for the diagnosis of bicuspid aortic valve: comparison with operative findings.

BACKGROUND: Bicuspid aortic valve (BAV) is associated with an increased risk of aortic valve (AV) dysfunction, aortic dissection, and infective endocarditis. Therefore, its accurate diagnosis is critical. The morphological features of AVs are generally evaluated by transthoracic echocardiography (TTE) or transesophageal echocardiography (TEE), however, the difference in the diagnostic capability of these imaging modalities for detecting BAV remains unclear. Here, we compared these 2 methods to determine their accuracy, and to clarify each role in the diagnosis of BAV. METHODS: This blind study evaluated 126 patients (age, 70.3 +/- 7.8 years) who subsequently underwent AV replacement. The number of AV cusps of each patient was estimated by TTE and TEE and compared to the number of AV written in the operative record. Patients with poor echocardiographic images were not excluded. RESULTS: Surgical findings showed 97 tricuspid AVs and 29 BAVs. The sensitivity, specificity, and accuracy for the diagnosis of BAV were 61%, 81%, and 77%, respectively, for TTE and 86%, 90%, and 89%, respectively, for TEE. The accuracy of TEE was significantly higher than that of TTE (p = 0.016). In non-calcified AVs, the accuracy of TTE was similar to that of TEE (96%, each) whereas in calcified AVs, TTE had a lower accuracy than TEE (72% vs 87%, p = 0.011). The feasibility was significantly higher for TEE than for TTE (98% vs 90%, p = 0.003). CONCLUSIONS: TEE provides higher accuracy and feasibility than TTE in the diagnosis of BAV, and it should therefore be indicated when morphological features of AVs cannot be evaluated by TTE.

Prognostic significance of residual functional mitral regurgitation in hospitalized heart failure patients with chronic atrial fibrillation and preserved ejection fraction after medical therapies.

BACKGROUND: Functional mitral regurgitation (MR) can be seen in patients with atrial fibrillation (AF), even without left-ventricular (LV) systolic dysfunction, as a result of left atrial enlargement. The purpose of this study was to evaluate the prognostic significance of residual functional MR in hospitalized heart failure patients with chronic AF and preserved LV ejection fraction (pEF) after medical therapies. METHODS: In this retrospective multi-center study, the determinants of post-discharge prognosis (cardiac death and re-hospitalization for worsening heart failure) were examined in 54 hospitalized heart failure patients with chronic AF and pEF at discharge. RESULTS: Of the 54 patients, 53 (98%) had mild or higher degrees of functional MR at hospitalization.At discharge, 47 (87%) still had functional MR, even after medical therapies [mild in 27 (50%), moderate in 16 (30%), and severe in 4 (7%)]. During the follow-up period (20 ± 16 months) after discharge, 16 (30%) patients met the composite end points. The grading of residual functional MR at discharge was the significant predictor of the end point (hazard ratio per one grade increase: 2.4, 95% confidence interval 1.1-5.5, p = 0.035). The greater the residual functional MR was, the lower the event-free rate from the end point was in the Kaplan-Meier curve analysis (p = 0.0069 for trend). CONCLUSIONS: A substantial proportion of patients hospitalized due to heart failure with chronic AF have residual functional MR at discharge, even with pEF after medical therapies, and the MR is related to future heart failure events.

The utility of fully automated real-time three-dimensional echocardiography in the evaluation of left ventricular diastolic function.

BACKGROUND: A novel real-time three-dimensional echocardiography (RT3DE) system allows fully automated quantification of the left ventricular (LV) volume throughout a cardiac cycle. This study aimed to investigate whether an LV time-volume curve, obtained using fully automated RT3DE, is useful in the evaluation of LV diastolic function. METHODS: First, 15 patients underwent simultaneous standard two-dimensional echocardiography (2DE), RT3DE, and cardiac catheterization to measure the time constant of the isovolumic-pressure decline (τ). From the LV time-volume curve obtained using RT3DE, peak early filling rate (PFR) during diastole was generated and indexed for LV end-systolic volume. Next 570 patients, who were scheduled for both 2DE and RT3DE examinations, were enrolled to investigate the association between PFR index and 2DE-evidenced diastolic dysfunction and clinical characteristics. RESULTS: Of the 585 patients, RT3DE analysis was adequate in 542 patients (feasibility 93%). In the 15 patients, PFR index showed significant correlation with τ (r=-0.65, p=0.009). In the remaining 527 patients, PFR index was related to age (r=-0.24, p<0.001) and e' (r=0.41, p<0.001). PFR index decreased in proportion to the grade of 2DE-evidenced diastolic dysfunction. All patients with normal diastolic function had a PFR index greater than 2.0. CONCLUSIONS: This study demonstrated that a novel, fully automated RT3DE-derived PFR index was the diagnostic tool of choice for the assessment of LV diastolic function.

Effect of azithromycin therapy on coronary circulation in patients with coronary artery disease.

This study examined the effect of azithromycin therapy on the coronary microcirculation using measurement of coronary flow velocity reserve (CFVR) by transthoracic Doppler echocardiography in 35 patients with coronary artery disease. CFVR increased significantly after azithromycin therapy (3.0 +/- 0.7 vs 3.5 +/- 0.7, p <0.001). The changes in CFVR were negatively correlated with changes in high-sensitivity C-reactive protein levels in patients receiving azithromycin.

Parathyroid hormone and systolic blood pressure accelerate the progression of aortic valve stenosis in chronic hemodialysis patients.

BACKGROUND: Aortic valve stenosis (AS) is a frequent complication contributing to poor prognosis in chronic hemodialysis (CHD) patients. However, little is known regarding the risk factors affecting AS progression. The purpose of this study was to define risk factors affecting AS progression in CHD patients. METHODS: We retrospectively investigated 34 consecutive CHD patients with asymptomatic AS (mild in 9, moderate in 20, severe in 5; aortic valve area (AVA), 1.31±0.31cm(2); mean age, 69±8years) who underwent followed-up paired transthoracic echocardiography with period of at least six months apart (22±9months). AS progression was evaluated using the absolute reduction in AVA per year. RESULTS: CHD patients were divided into 20 patients with rapid progression (AVA reduction, >0.1cm(2) per year) and 14 with slow progression (AVA reduction, ≤ 0.1cm(2) per year). Serum parathyroid hormone (PTH) level was significantly higher in patients with rapid progression than in those with slow progression [343±489pg/ml vs. 76±80pg/ml, P<0.05]. In univariate analysis, AS progression by absolute AVA reduction per year was associated with age, PTH level, initial AVA, systolic blood pressure (SBP), diastolic blood pressure, total cholesterol, and left ventricular diameter at end-diastole and end-systole. Multiple regression analysis indicated that serum PTH level and SBP remained independently associated with AS progression. CONCLUSIONS: AS progression was accelerated in the presence of high PTH and SBP. Careful monitoring and intensive treatment of these parameters may have a beneficial effect on secondary prevention in CHD patients.

Simultaneous assessment of endothelial function and morphology in the brachial artery using a new semiautomatic ultrasound system.

The accuracy of measurements of the intima-media thickness (IMT) and flow-mediated dilatation (FMD) of the brachial artery made using a new semiautomated ultrasound system and the relationships among those parameters and the Framingham Risk Score (FRS) as a predictor of coronary heart disease (CHD) are unknown. We enrolled 70 subjects, including 47 patients with cardiovascular risk factors and 23 normal healthy volunteers. IMT and FMD were simultaneously measured using a new semiautomated ultrasound system, and the measurements were compared with those obtained manually as a reference standard (study 1). In addition, we enrolled 200 consecutive patients with risk factors but no CHD to examine the relationships among IMT, FMD and the FRS. The optimal cutoff values of FMD and IMT were determined in 200 patients without CHD, and the subjects were classified into four groups. The 10-year Framingham risks for each group were compared (study 2). FMD and IMT measurements made using the new semiautomated ultrasound system showed a good correlation with the measurements determined manually (study 1). Furthermore, FMD and IMT showed a significant correlation with the FRS. The 10-year Framingham risk was markedly higher in group D (FMD <5.5% and IMT >0.3 mm; 19.0±11.3%; study 2). In conclusion, the measurements made using a new semiautomated ultrasound system provided reliable and simultaneous evaluations of IMT and FMD. The combination of IMT and FMD measurements of the brachial artery may be beneficial for risk stratification of patients with cardiovascular risk factors but no CHD.

Prognostic value of aortic valve area index in asymptomatic patients with severe aortic stenosis.

Recently, an aortic valve area (AVA) index (AVAI) <0.6 cm(2)/m(2) was proposed as an indicator of severe aortic stenosis. The purpose of the present study was to clarify the prognostic value of the AVAI. We identified 103 consecutive asymptomatic patients (mean age 72 ± 11 years) with severe aortic stenosis, defined by an AVA of <1.0 cm(2), who had not undergone aortic valve replacement on initial evaluation. During follow-up (median 36 ± 27 months), 31 aortic valve replacements and 20 cardiac deaths occurred. Multivariate analysis revealed that an AVAI <0.6 cm(2)/m(2) (hazard ratio 2.6, 95% confidence interval 1.1 to 6.3; p = 0.03) and peak aortic jet velocity (Vp) >4.0 m/s (hazard ratio 2.6, 95% confidence interval 1.2 to 5.8; p = 0.02) were associated with cardiac events but that an AVA <0.75 cm(2) was not. The event-free survival of patients with an AVAI of ≥0.6 cm(2)/m(2) was better than that for those with an AVAI <0.6 cm(2)/m(2) (86% vs 41% at 3 years, p <0.01). Furthermore, patients with an AVAI of ≥0.6 cm(2)/m(2) and Vp of ≤4.0 m/s showed an excellent prognosis, but those without these findings had poorer outcomes. In conclusion, AVAI is a powerful predictor of adverse events in asymptomatic patients with severe aortic stenosis. Furthermore, the combination of AVAI and Vp provides additional prognostic information. Watchful observations are required for timely aortic valve replacement in patients with an AVAI of <0.6 cm(2)/m(2) or a Vp >4.0 m/s.

Cardiomyocyte triglyceride accumulation and reduced ventricular function in mice with obesity reflect increased long chain Fatty Acid uptake and de novo Fatty Acid synthesis.

A nonarteriosclerotic cardiomyopathy is increasingly seen in obese patients. Seeking a rodent model, we studied cardiac histology, function, cardiomyocyte fatty acid uptake, and transporter gene expression in male C57BL/6J control mice and three obesity groups: similar mice fed a high-fat diet (HFD) and db/db and ob/ob mice. At sacrifice, all obesity groups had increased body and heart weights and fatty livers. By echocardiography, ejection fraction (EF) and fractional shortening (FS) of left ventricular diameter during systole were significantly reduced. The V(max) for saturable fatty acid uptake was increased and significantly correlated with cardiac triglycerides and insulin concentrations. V(max) also correlated with expression of genes for the cardiac fatty acid transporters Cd36 and Slc27a1. Genes for de novo fatty acid synthesis (Fasn, Scd1) were also upregulated. Ten oxidative phosphorylation pathway genes were downregulated, suggesting that a decrease in cardiomyocyte ATP synthesis might explain the decreased contractile function in obese hearts.

Aortic valve calcification in mild primary hyperparathyroidism.

CONTEXT: It is unclear whether cardiovascular disease is present in primary hyperparathyroidism (PHPT). OBJECTIVE: Aortic valve structure and function were compared in PHPT patients and population-based controls. DESIGN: This is a case-control study. SETTING: The study was conducted in a university hospital metabolic bone disease unit. PARTICIPANTS: We studied 51 patients with PHPT and 49 controls. OUTCOME MEASURES: We measured the aortic valve calcification area and the transaortic pressure gradient. RESULTS: Aortic valve calcification area was significantly higher in PHPT (0.24 ± 0.02 vs. 0.17 ± 0.02 cm(2), p<0.01), although there was no difference in the peak transaortic pressure gradient, a functional measure of valvular calcification (5.6 ± 0.3 vs. 6.0 ± 0.3 mm Hg, P = 0.39). Aortic valve calcification area was positively associated with PTH (r = 0.34; P < 0.05) but not with serum calcium, phosphorus, or 25-hydroxyvitamin D levels or with calcium-phosphate product. Serum PTH level remained an independent predictor of aortic valve calcification area after adjustment for age, sex, body mass index, smoking status, history of hypercholesterolemia and hypertension, and estimated glomerular filtration rate. CONCLUSIONS: Mild PHPT is associated with subclinical aortic valve calcification. PTH, but not serum calcium concentration, predicted aortic valve calcification. PTH was a more important predictor of aortic valve calcification than well-accepted cardiovascular risk factors.

Direct measurement of multiple vena contracta areas for assessing the severity of mitral regurgitation using 3D TEE.

OBJECTIVES: The aim of this study was to determine whether direct measurement of multiple-jet vena contracta (VC) areas by real-time 3-dimensional (3D) transesophageal echocardiography is an accurate method for measuring the severity of mitral regurgitation (MR) in patients with multiple MR jets. BACKGROUND: Because of the conflicting requirements of Doppler and imaging physics, measuring VC using 2-dimensional (2D) echocardiography is a difficult procedure for assessing MR severity. A real-time 3D echocardiographic measurement of the VC area has been validated in a single jet of MR, but the applicability of this method for multiple jets is unknown. METHODS: Two-dimensional and 3D transesophageal echocardiography was performed in 60 patients with multiple functional MR jets. MR severity was assessed quantitatively using the effective regurgitant orifice area derived from 3D left ventricular volume and thermodilution data (EROAstd). Manual tracings of multiple 3D VC areas in a cross-sectional plane through the VC were obtained, and the sum of the areas was compared using EROAstd. Similarly, 2D measurement of VC diameter was obtained from a 2D transesophageal echocardiographic view to optimize the largest legion size in each jet. All VC diameters were summed and compared with EROAstd. RESULTS: The correlation of the sum of the multiple 3D VC areas with EROAstd (r = 0.90, p < 0.01) was higher than that of the sum of the multiple 2D VC diameters (r = 0.56, p < 0.01), particularly with MR degrees greater than mild (r = 0.80, p < 0.01 vs. r = 0.05, p = 0.81) and in cases of 3 or more regurgitant jets (r = 0.91, p < 0.01 vs. r = 0.46, p = 0.05). CONCLUSIONS: Direct measurement of multiple VC areas using 3D transesophageal echocardiography allows for assessing MR severity in patients with multiple jets, particularly for MR degrees greater than mild and in cases of more than 2 jets, for which geometric assumptions may be challenging.

Alteration in subendocardial and subepicardial myocardial strain in patients with aortic valve stenosis: an early marker of left ventricular dysfunction?

BACKGROUND: It has been suggested that myocardial systolic impairment may not be accurately detected by the evaluation of endocardial excursion alone. The aim of this study was to test the hypothesis that changes in left ventricular (LV) subendocardial and subepicardial strain are sensitive markers of severity of aortic stenosis (AS) and LV function in patients with AS. METHODS: Transthoracic echocardiography was performed in 73 consecutive patients with AS who had preserved systolic function and in 20 controls. Longitudinal strain, subendocardial radial strain, subepicardial radial strain, and transmural radial strain were measured using LV apical and short-axis images. RESULTS: The 73 patients enrolled in this study were classified according to AS severity: mild (n = 10), moderate (n = 15), or severe (n = 48). Although transmural and subepicardial radial strain showed similar values in all groups, subendocardial radial strain and longitudinal strain could differentiate mild or moderate AS from severe AS. Only the ratio of subendocardial to subepicardial radial strain (the bilayer ratio) decreased significantly as the severity of AS increased. Bilayer ratio showed weak correlations with LV ejection fraction (r = 0.37) and E/E' ratio (r = -0.33) and moderate correlations with LV mass (r = -0.55) and aortic valve area (r = 0.71). Moreover, bilayer ratio was independently associated with AS severity (P = .001). In 21 patients who underwent aortic valve replacement, subendocardial radial strain and bilayer ratio increased 7 days after surgery, whereas other echocardiographic parameters of LV function showed no improvement. CONCLUSIONS: Bilayer ratio can reliably differentiate patients with varying degrees of AS severity and is a sensitive marker of LV function. These findings suggest that the evaluation of subendocardial and subepicardial radial strain might be a novel method for assessing LV mechanics in patients with AS.

Accurate measurement of mitral annular area by using single and biplane linear measurements: comparison of conventional methods with the three-dimensional planimetric method.

AIMS: The planimetry method using three-dimensional (3D) echocardiography is useful for providing an accurate mitral annulus area (MAA) value. However, this method is relatively unavailable. Therefore, we evaluated the accuracy of conventional methods for MAA measurement compared with that of 3D planimetry. METHODS AND RESULTS: Two-dimensional (2D) and 3D transoesophageal echocardiography (TEE) were performed in 70 patients. The mitral annulus diameter (MAD) was measured using four standard TEE imaging planes: four-chamber (4Ch), two-chamber (2Ch), anterior-posterior (LAX), and commissure-commissure (CC). MAA was calculated using a single diameter based on that of a circle and using two diameters based on that of an ellipse. MAA measurements using the single 4Ch MAD method (r = 0.84, P < 0.001), and two anatomically orthogonal MAD method in 4Ch/2Ch (r = 0.93, P < 0.001) and LAX/CC (r = 0.97, P < 0.001) planes correlated with 3D planimetric MAA measurements. Further analysis with Bland-Altman plots revealed that the LAX/CC MAD measurement exhibited the closest limits of agreement with the 3D planimetric MAA measurement. Notably, in patients showing an elliptical annulus shape, only LAX/CC MAD, but not 4Ch or 4Ch/2Ch MAD, provided results comparable with those of 3D planimetric MAA measurements. However, in patients with a circular annulus shape, reliable MAA measurements can be achieved using either single 4Ch MAD or any biplane MAD. CONCLUSION: Conventional LAX/CC MAD can be recommended for MAA measurements in a diverse patient population. This method is applicable as an alternative to the 3D planimetric method, regardless of the mitral annulus shape.

Contrast-enhanced sonography as a novel tool for assessment of vascular malformations.

BACKGROUND: Vascular malformations with arteriovenous shunt components can cause significant disability, chronic pain, and functional impairment. Effective treatment may require serial procedures, yet an imaging modality optimized to control cost and reduce radiation exposure in this predominantly pediatric population has not yet been identified. METHODS AND RESULTS: We describe the use of contrast-enhanced sonography as a novel tool to define vascular anatomy and localize arteriovenous shunting in a young patient with a symptomatic vascular malformation. CONCLUSIONS: This method may effectively reduce radiation exposure and cost, and additionally provide unique information about arteriovenous shunting, offering a novel imaging application for patients with these conditions.

In-vivo clinical validation of cardiac deformation and strain measurements from 4D ultrasound.

An important goal in clinical cardiology is the non-invasive quantification of regional cardiac deformation. While many methods have been proposed for the estimation of 3D left ventricular deformation and strains derived from 4D ultrasound, currently there is a lack of in vivo clinical validation of these algorithms on humans. In this paper, we describe the experiments used in validating cardiac deformation and strain estimates of 4D ultrasound using correlation-based optical flow tracking on two different COPD patients with normal left ventricular function. Validation of the algorithm was done by 1) validation of cardiac volume across multiple scans of the same patient and 2) validation of the repeatability of cardiac displacement and strain results from multiple scan acquisitions of the same patient. The preliminary results are encouraging with our algorithm producing consistent cardiac volume and strain results across multiple acquisitions. Furthermore, our derived 4D cardiac strains showed qualitatively correct results. We also observed particularly interesting results in the radial displacements of the posterior and lateral walls of our COPD patients.

Detection of restenosis after percutaneous coronary intervention in three major coronary arteries by transthoracic Doppler echocardiography.

BACKGROUND: The aim of this study was to evaluate the diagnostic potential of coronary flow velocity reserve (CFR) measurement by transthoracic Doppler echocardiography (TTDE) to detect restenosis in the 3 major coronary arteries: the left anterior descending coronary artery, right coronary artery, and left circumflex coronary artery. METHODS: The lesions of 175 patients who were scheduled for follow-up coronary angiography and TTDE 6 months after undergoing stents implantation were studied. CFR was assessed by TTDE in the targeted arteries into which stents had been implanted. RESULTS: Coronary stents were implanted in a total of 238 angiographic lesions in 175 patients. Doppler recordings of coronary flow in the 3 major arterial lesions were obtained in 211 of the 238 angiographic lesions (89% feasibility). CFR was significantly lower in lesions with restenosis than those without restenosis (1.70 +/- 0.32 vs 2.65 +/- 0.66, P < .01). A CFR value < 2.0 was 89% sensitive and 91% specific for detecting restenosis in the 3 major coronary arteries. Sensitivity and specificity were 86% and 91%, respectively, in the left anterior descending coronary artery (95% feasibility); 92% and 92%, respectively, in the right coronary artery (85% feasibility); and 91% and 92%, respectively, in the left circumflex coronary artery (81% feasibility). CONCLUSION: CFR assessment by TTDE is an accurate method for monitoring restenosis, not only in the left anterior descending but also in the right and left circumflex coronary arteries in patients previously subjected to percutaneous coronary intervention.

Usefulness of a combination of systolic function by left ventricular ejection fraction and diastolic function by E/E' to predict prognosis in patients with heart failure.

Left ventricular (LV) ejection fraction (EF) was known as a conventional predictor of heart failure (HF). However, early transmitral flow velocity (E)/early diastolic velocity of mitral annulus (E') correlated well with LV end-diastolic pressure, and E/E' ratio >15 was an excellent predictor of adverse outcomes in patients with HF. This study was designed to determine the prognostic value of a new combined index, E/E' ratio and LVEF, in patients with HF. One hundred twenty-six consecutive patients hospitalized with HF underwent comprehensive echocardiographic-Doppler study when ready for discharge. Patients were divided into the 4 groups of group I (LVEF >40% and E/E' ratio <15), group II (EF >40% and E/E' ratio >or=15), group III (EF or=15). The ability of this index to determine the primary end point (rehospitalization for HF or cardiac death) was assessed. Patients with significant valvular disease were excluded. Of 126 patients, 110 met the inclusion criteria. Follow-up was complete for 108 of 110 patients at 351 +/- 252 days after discharge. There were 27, 30, 21, and 30 patients in groups I, II, III, and IV, respectively. There were 52 patients with the primary end point. On univariate analysis, E/E' ratio, group IV, E', and age were significant predictors. In multivariable analysis, the most powerful independent prognostic indicator of events was group IV (hazard ratio 12.6, 95% confidence interval 2.2 to 74.2, p = 0.005). In conclusion, a new index, a combination of LVEF and E/E' ratio, allowed the identification of patients at higher risk of readmission and cardiac death in patients with HF.

QUANTITATIVE VALIDATION OF OPTICAL FLOW BASED MYOCARDIAL STRAIN MEASURES USING SONOMICROMETRY.

Dynamic cardiac metrics, including myocardial strains and displacements, provide a quantitative approach to evaluate cardiac function. However, in current clinical diagnosis, largely 2D strain measures are used despite the fact that cardiac motions are complex 3D volumes over time. Recent advances in 4D ultrasound enable the capability to capture such complex motion in a single image data set. In our previous work, a 4D optical flow based motion tracking algorithm was developed to extract fully 4D dynamic cardiac metrics from such 4D ultrasound data. In order to quantitatively evaluate our tracking method, in-vivo coronary artery occlusion experiments at various locations were performed on three canine hearts. Each dog was screened with 4D ultrasound and sonomicrometry data was acquired during each occlusion study. The 4D ultrasound data from these experiments was then analyzed with our tracking method and estimated principal strain measures were directly compared to those recorded by sonomicrometry, and showed strong agreement. This is the first validation study of optical flow based strain estimation for 4D ultrasound with direct comparison with sonomicrometry using in-vivo data.