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Background: Basal interventricular septum (IVS) hypertrophy (BSH) with reduced basal IVS contraction and IVS-aorta angle is frequently associated with aortic stenosis (AS). BSH shape suggests compression by the longitudinally elongated ascending aorta, causing basal IVS thickening and contractile dysfunction, further suggesting the possibility of aortic wall shortening to improve the BSH. Surgical aortic valve replacement (SAVR), as opposed to transcatheter AVR (TAVR), includes aortic wall shortening by incision and stitching on the wall and may potentially improve BSH. We hypothesized that BSH configuration and its contraction improves after SAVR in patients with AS., Methods and results: In 32 patients with SAVR and 36 with TAVR for AS, regional wall thickness and systolic contraction (longitudinal strain) of 18 left ventricular (LV) segments, and IVS-aorta angle were measured on echocardiography. After SAVR, basal IVS/average LV wall thickness ratio, basal IVS strain, and IVS-aorta angle significantly improved (1.11±0.24 to 1.06±0.17; -6.2±5.7 to -9.1±5.2%; 115±22 to 123±14°, P<0.001, respectively). Contractile improvement in basal IVS was correlated with pre-SAVR BSH (basal IVS/average LV wall thickness ratio or IVS-aorta angle: r=0.47 and 0.49, P<0.01, respectively). In contrast, BSH indices did not improve after TAVR., Conclusions: In patients with AS, SAVR as opposed to TAVR improves associated BSH and its functional impairment.

Background:  Different influences of left ventricular (LV) remodeling on anterior and posterior mitral leaflet (AML and PML) tethering in ischemic mitral regurgitation (MR) has not been fully investigated. We hypothesized that progressive outward displacement of papillary muscles, including posterior vector, may cause greater tethering to PML compared to AML., Methods and Results:  In 79 patients with LV ejection fraction <50% and 20 controls, LV sphericity, AML and PML tethering angles, apical and posterior displacement of coaptation, mitral annular area, and severity of MR (vena contracta width) were measured using 3-D echocardiography. To examine different influences of LV remodeling on AML and PML tethering, interaction between AML/PML and LV sphericity was tested using multiple regression analysis. Both AML and PML tethering significantly increased with increased LV sphericity (r=0.59 and 0.65, P<0.001). Multiple regression yielded a significant interaction term between AML vs. LV sphericity and PML vs. LV sphericity (t=3.69, P<0.001), indicating greater influence from LV remodeling on PML compared to that for the AML. Multivariate analysis demonstrated independent contributions to MR severity from PML tethering primarily along with posterior and apical displacement of coaptation., Conclusions:  LV remodeling augments tethering of both AML and PML, with greater influence on PML.

Background: Precise evaluation of the aortic root geometry prior to transcatheter aortic valve implantation is important for procedural success in patients with aortic stenosis (AS). To determine the potential for 3-dimensional transesophageal echocardiography (3DTEE), the aims of the present study were: (1) to assess the accuracy of 3DTEE measurements of the aortic root using multidetector computed tomography (MDCT) as a reference, and (2) to examine whether aortic root geometry differs between patients with and without AS., Methods and Results:   3DTEE and contrast-enhanced MDCT were performed in 35 patients. Multiplanar reconstruction was used to measure the left ventricular outflow tract (LVOT) and aortic annulus diameter/area, aortic valve area (AVA), and distances between the annulus and coronary artery ostium. The same 3DTEE measurements were performed in patients with (n=71) and without AS (n=80). Aortic annular and LVOT areas measured by 3DTEE were slightly but significantly smaller compared with values obtained with MDCT. Both methods revealed that the aortic annulus and LVOT have an oval shape. Aortic annular and LVOT area, AVA and the distances between the aortic annulus and the coronary ostia correlated well between the 2 modalities. Only minor differences in aortic root geometry were observed between patients with AS and those without., Conclusions: The geometry of the aortic annulus can be reliably evaluated using 3DTEE as an alternative to MDCT for the assessment of aortic root.

Background: Aging and westernization of lifestyle has accelerated the prevalence and severity of atherosclerotic cardiovascular diseases in the Japanese population. The aim of this study was to examine the prevalence of complex plaque formation in the descending thoracic aorta (DTA) as assessed by real-time 3-dimensional transesophageal echocardiography (3DTEE) and its relation to clinical factors., Methods and Results: A prospective analysis of atherosclerotic plaque in the DTA of 350 consecutive patients who were clinically indicated for real-time 3DTEE was performed. Systematic assessment of the DTA plaques was performed using a biplane mode from the aorta at the level of the stomach to the aortic arch. When a large plaque (>4mm) was identified, detailed 3-dimensional (D) observations were performed using a 3D zoom mode. Complex plaque was defined as either mobile or an ulcer-like pouch in the DTA. Complex plaques were detected in 51 patients (15%), who were more advanced in age and had a higher prevalence of chronic kidney disease. A multivariate analysis revealed that the presence of complex plaque was an independent predictor of renal impairment., Conclusions: The prevalence of complex plaque was not low in the this Japanese study population. A close association between complex plaque and renal dysfunction raises the possibility that complex plaque in the DTA is a potential cause of renal dysfunction.

Background: The precise mechanism of takotsubo-like left ventricular (LV) dysfunction remains unclear., Methods and Results: Eight consecutive patients with takotsubo-like LV dysfunction were studied. In the acute phase and 3 weeks later, the coronary flow velocity spectrum and coronary flow velocity reserve (CFVR) were recorded by Doppler guidewire. The deceleration time of diastolic velocity (DDT; ms) was measured from the peak diastolic velocity to the point where the extrapolated line intersected the baseline. In all cases, CFVR of the 3 coronary arteries increased during follow-up (1.7+/-0.5 to 2.4+/-0.5 for the left anterior descending artery (p < 0.05), 1.7+/-0.5 to 2.7+/-0.8 for the left circumflex artery (p < 0.05) and 1.7+/-0.3 to 2.5+/-0.4 for the right coronary artery (p < 0.05)). In addition, the DDT of all coronary arteries increased during follow-up., Conclusions: Decreased CFVR and short DDT were demonstrated in patients with takotsubo-like transient LV dysfunction in the acute phase, and these findings improved 3 weeks later, which suggests that coronary microvascular dysfunction may be a causative mechanism.

The purpose of this study was to determine whether the elimination or the alleviation of hyperglycemia would improve coronary flow velocity reserve (CFVR) using transthoracic Doppler echocardiography (TTDE). CFVR was measured by TTDE in the left anterior descending coronary artery in 49 poorly controlled diabetic patients before and after antidiabetic treatment and 15 well controlled diabetic patients also underwent the same measurements. The fasting blood glucose level in the poorly controlled patients reduced from 270 +/-106 mg/dl to 116+/-39 mg/dl at 20+/-15 days after the intensive treatment. Although baseline coronary flow velocity (CFV) did not change between the 2 measurements (19.9+/-6.9 cm/s vs 19.0+/-5.4 cm/s, p=NS), the hyperemic CFV increased significantly after the treatment (47.3+/-13.4 cm/s vs 55.4+/-13.2 cm/s, p<0.001). Thus, the CFVR improved significantly after the treatment (2.47+/-0.55 vs 2.98+/-0.56, p<0.001). Although there was minimal improvement in the control group (2.37+/-0.38 vs 2.50+/-0.37, p<0.05), the improvement in CFVR was significantly greater in the poorly controlled patients with intensive treatment (0.51+/-0.33 vs 0.12+/-0.19, p<0.001) than that in the control group. These results suggest that optimal hypoglycemic therapy is important to improve the CFVR in poorly controlled diabetic patients.

Accurate interpretation of dobutamine stress echocardiography (DSE) needs expertise. Color kinesis (CK) allows objective assessment of wall motion (WM), and its feasibility and accuracy are enhanced under harmonic imaging with contrast agents. To explore its utility, CK was performed in 41 unselected patients during contrast-enhanced DSE. After bolus injection of Levovist, the CK image was acquired in the apical 4- and 2-chamber views at baseline and peak stress using the ultraharmonic mode. Quad screen format with second harmonic imaging after another injection of Levovist was also obtained as a reference. Regional WM (12 segments in the apical view) was independently assessed by both methods. Heart rate increased from 67 beats/min at baseline to 135 beats/min (88% of age predicted maximal heart rate) at peak stress. The CK image was successfully obtained in all patients at baseline and in 38/41 patients at peak stress. CK tracked endocardial motion accurately in 93% (456/492) of left ventricular segments at baseline and 87% (427/492) at peak stress. The concordance rate of normal and abnormal WM between the 2 methods was 86% (392/456, Kappa 0.61) at baseline and 85% (362/427, kappa 0.53) at peak stress. Among the 38 patients in whom both methods were completed, the standard quad screen display showed abnormal DSE results in 17 patients and 28/114 vascular territories. The sensitivity, specificity and diagnostic accuracy of CK for detecting abnormal findings were, respectively, 71% (12/17), 90% (19/21) and 82% (31/38) in patients and 57% (16/28), 97% (83/86) and 87% (99/114) in vascular territories. The application of CK was highly feasible during contrast-enhanced DSE and gave an objective assessment of WM. This method can be a valuable adjunct to the conventional interpretation of DSE.

Recent developments in tissue harmonic imaging and intravenous contrast agents have enhanced left ventricular endocardial border delineation (EBD). In a total of 48 patients with poor quality images, apical 4- and 2-chamber views were obtained with fundamental, tissue harmonic and contrast harmonic imaging with or without intravenous Levovist, an air-filled contrast agent. The left ventricle (LV) was divided into 12 segments, and the EBD of each segment was scored: (1) not visible, (2) barely visible, (3) well delineated. The EBD index (EBDI), defined as the sum of the endocardial scores divided by 12 was obtained for each patient. Of a total of 576 LV segments, 231 were scored as 1 by fundamental imaging and that number decreased to 125 segments by tissue harmonic imaging and 116 segments by fundamental imaging with Levovist. The number of segments scored as 1 decreased to 38 segments by tissue harmonic imaging with Levovist, and to 29 segments by contrast harmonic imaging with Levovist. The EBDI by fundamental imaging was 1.85+/-0.29, which improved significantly with the addition of Levovist (2.10+/-0.36, p<0.001) and was nearly identical to that by tissue harmonic imaging (2.15+/-0.32, p=NS). Tissue and contrast harmonic imaging with Levovist further enhanced the EBDI (2.43+/-0.26, 2.51+/-0.27, respectively). Levovist enhances EBD, even in the fundamental mode, to the level obtained with tissue harmonic imaging. Tissue harmonic and contrast harmonic imaging are the best modalities for enhancing EBD after Levovist injection.

To clarify whether the myocardial perfusion abnormalities observed on harmonic power Doppler imaging (HPDI) during hyperemia are related to a decrease in coronary flow velocity reserve (CFVR), HPDI and CFVR were measured in the left anterior descending coronary artery (LAD) territory of 75 patients. During continuous infusion of Levovist, dual-frame triggered apical 4-chamber views were obtained at rest and during adenosine triphosphate (ATP) infusion. The persistence of perfusion defects during ATP infusion or stress-induced defects in the LAD territory was defined as abnormal. Both HPDI and coronary flow velocity recordings of adequate quality were successfully obtained in 73 patients, and 37 patients showed abnormal myocardial perfusion. CFVR was significantly lower in patients with abnormal perfusion than in patients who had normal findings (1.38+/-0.38 vs 2.60+/-0.76, p<0.001). A CFVR less than 1.9 had a sensitivity of 89% (33/37) and a specificity of 89% (32/36) for predicting the presence of abnormal myocardial perfusion. This study demonstrates that myocardial perfusion abnormalities observed during HPDI using ATP stress are closely correlated to a decrease in CFVR and may reflect significant stenosis or microvascular damage in the LAD territory.