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While good ohmic contact formation has been achieved on both p-GaN and n-AlGaN surfaces, the turn-on and operating voltages of AlGaN-based deep-ultraviolet light-emitting diodes (DUV-LEDs) remain very high. We find that this critical problem is mainly caused by the large difference between the annealing temperatures required for ohmic contact formation on the p-GaN and high Al-fraction n-AlGaN surfaces. We studied the effects of the high-temperature annealing treatments required for n-ohmic contact formation on the subsequent p-ohmic contact formation process in DUV-LEDs. The results show that post-annealing treatment at high temperature is necessary to form an ohmic contact on n-Al0.7Ga0.3N, but a treatment temperature of 900°C or more could cause severe degradation of the specific contact resistivity and the bulk resistivity of p-GaN. We conclude that 900°C is the optimum temperature to form an ohmic contact on n-Al0.7Ga0.3N in DUV-LEDs, where p-GaN and n-Al0.7Ga0.3N act as the p- and n-ohmic contact layers, respectively. We also found that the specific contact resistivity of p-GaN can be reduced by an additional low-temperature annealing treatment after the high-temperature annealing step; this effect can be attributed to the enhancement of the hole concentration in the p-GaN surface contact region. Finally, DUV-LEDs that emit at 280 nm were fabricated using four different annealing treatments during processing. A considerable reduction in the series resistance and thereby in the operating voltage was confirmed using the annealing process proposed above, consisting of a high-temperature anneal at 900°C followed by a low-temperature anneal at 500°C for 3 min.

Hexagonal boron nitride (h-BN) is an attractive wide-bandgap material for application to emitters and detectors operating in the deep ultraviolet (DUV) spectral region. The optical transmittance of h-BN in the DUV region is particularly important for these devices. We report on the deposition of thick h-BN films (&gt, 200 nm) on Al0.7Ga0.3N templates via radio-frequency sputtering, along with the realization of ultrahigh transmittance in the DUV region. The fraction of the gas mixture (Ar/N2) was varied to investigate its effects on the optical transmittance of BN. DUV light transmittance of as high as 94% was achieved at 265 nm. This value could be further enhanced to exceed 98% by a post-annealing treatment at 800 &deg, C in a N2 ambient for 20 min. The phase of the highly DUV&ndash, transparent BN film was determined to be a purely hexagonal structure via Raman spectra measurements. More importantly, these deposition processes were performed at a low temperature (300 &deg, C), which can provide protection from device performance degradation when applied to actual devices.

The external quantum efficiency (EQE) in electrically injected AlGaN-based deep-ultraviolet light-emitting diodes (DUV-LEDs) is severely limited by their poor current injection efficiency (CIE). We report improvement in the CIE via controlling the relaxation of strains in the p-AlGaN hole injection layer (HIL) and the electron blocking layer (EBL). Simulation results show that an unrelaxed strain in the HIL associated with a relaxed strain in EBL can significantly enhance CIE. Deeper analysis indicates that high hole concentrations can be generated at HIL/EBL interface by strain-induced piezoelectric fields, which can then provide abundant numbers of holes for injection into quantum wells. Two sub-280 nm DUV-LEDs were fabricated with specific designs for different strain relaxations in the p-AlGaN HIL by changing the HIL thickness from 200 to 20 nm. The strain difference was identified using Raman spectroscopy. Electroluminescence measurements demonstrated much higher EQE in the strained-HIL DUV-LEDs. By separating the EQE contributions of three efficiencies, i.e. the CIE, the radiative recombination efficiency and the light extraction efficiency, we found that the EQE enhancement could mainly be attributed to the improved CIE, which agreed well with the simulation results.

Although the volume overload of pulmonary circulation improves after atrial septal defect (ASD) closure, the increasing left ventricular preload may contribute to mitral regurgitation (MR) deterioration. We aimed to evaluate the impact of MR after transcatheter ASD closure on clinical outcomes in adults. A total of 288 consecutive patients who underwent transcatheter ASD closure were enrolled. Changes in MR were assessed at 1 month after the procedure. The end point was defined as cardiovascular events. After the procedure, MR ameliorated in 3 patients and unchanged in 253, whereas MR deteriorated in 32. During a median follow-up of 24 months, patients with MR deterioration had no cardiovascular events, and the event-free survival rate was not different between patients with MR deterioration and those with MR amelioration or no-change (p = 0.355). Even in patients with MR deterioration, the New York Heart Association functional class improved after the procedure, with no cases of worsening functional class. Multivariate logistic regression analysis showed that MR deterioration was independently related to advanced age and female gender. The degree of enlargement of mitral valve annulus diameter after the procedure was greater in patients with MR deterioration than in those with MR amelioration or no-change, and it was correlated with the degree of MR deterioration. In conclusion, MR deterioration occurs in a minority of adult patients after transcatheter ASD closure; however, it is not linked with adverse outcomes. MR deterioration may be provoked by geometric changes in mitral valve annulus, especially in women with advanced age.

Although numerous studies have shown an association between a patent foramen ovale (PFO) and cryptogenic cerebrovascular accidents (CVA), there has been no definitive control study that demonstrated the benefit of percutaneous device closure of a PFO compared to medical therapy in patients with CVA. Additionally, few clinical data exist for Japanese patients in this field. We demonstrate the initial experiences in catheter closure of a PFO as secondary prevention of CVA in Japan. Catheter closure of a PFO was attempted in 7 patients who were diagnosed with cryptogenic CVA. Mean age at the procedure was 54 ± 19 years. The presence of spontaneous interatrial right-to-left shunts was demonstrated by transesophageal contrast echocardiography without Valsalva maneuver in all of the patients. Amplatzer Cribriform device (n = 4) or Amplatzer PFO Occluder (n = 3) was used for the procedure and was successfully deployed. Device-related complications were not observed at the time of the procedure or during the follow-up period (mean period of 16 ± 9 months). Catheter closure of a PFO could be safely performed with Amplatzer Cribriform or Amplatzer PFO Occluder. This procedure may contribute to prevention of recurrent cryptogenic CVA in Japanese patients.

This study sought to evaluate the usefulness of real-time three-dimensional (3D) transesophageal echocardiography (TEE) to guide the repair of multiple atrial septal defects (ASDs). Of 212 consecutive patients with secundum ASD who were scheduled for transcatheter closure of their ASDs, 27 had multiple ASDs. These patients underwent two-dimensional (2D) transthoracic echocardiography, 2D TEE, and 3D TEE. Overall, 18 patients had two defects, and 9 patients had three or more defects. The latter group included three patients with multi-fenestrated defects. Optimal 3D images were obtained in 93 % of the patients. In patients with two defects, information on the positional relation of the defects was obtained using 2D TEE and 3D TEE in 71 and 94 % of patients, respectively (P = 0.22). The positional relations of the defects could not be evaluated with 2D TEE in patients with three or more defects, whereas it could be evaluated with 3D TEE in all of these patients (0 vs. 100 %, P = 0.008). In all patients, 3D TEE proved superior to 2D TEE for providing sufficient information (96 vs. 48 %, P = 0.002). Procedural success was obtained in 26 patients (96.3 %), without complications. Transcatheter closure of multiple ASDs under 3D TEE guidance is effective and safe. Real-time 3D TEE can provide useful information regarding complex ASD morphology. It can thus contribute to developing a successful treatment strategy, especially in patients with three or more defects.

Objective This study evaluated the effect of echocardiographic left ventricular (LV) diastolic dysfunction on acute congestive heart failure after transcatheter atrial septal defect (ASD) closure in elderly patients. Background Although there is concern that LV diastolic dysfunction develops acute congestive heart failure after ASD closure, limited information is available regarding the influence, especially in elderly patients with severe LV diastolic dysfunction. Methods Two hundred consecutive patients older than 60 years were divided into 3 groups according to echocardiographic LV diastolic dysfunction: severe (early diastolic mitral annular velocity [e’]

Background Although it has been demonstrated that cardiac remodeling and exercise capacity improve after transcatheter closure of atrial septal defect (ASD), little is known about long-term benefits in middle-aged and elderly patients with a reduction in cardiopulmonary function. Objectives To evaluate long-term extent and time course of improvements in cardiac remodeling and exercise capacity in those patients. Methods: Twenty ASD patients ≥ 40 years of age with a reduction in cardiopulmonary function (predicted peak oxygen uptake [VO2] 12 months after the procedure. Results At 1 month after the procedure, significant decreases in right ventricular (RV) end-diastolic diameter (38.2 ± 4.4 to 31.9 ± 4.4 mm; P < 0.001) and RV/left ventricular end-diastolic diameter ratio (0.95 ± 0.17 to 0.71 ± 0.13; P < 0.001) occurred, and they were maintained during the follow-up period. Normal RV size was achieved in 11 of 18 patients with RV enlargement. Predicted peak VO2 did not change at 1 month and 3 months, but it improved significantly after 6 months (53.6 ± 6.5 to 62.1 ± 12.6%; P < 0.01). Sixteen of the 20 patients showed improved predicted peak VO2. Conclusions Cardiac remodeling and exercise capacity could be improved over the long-term period after transcatheter closure of ASD in middle-aged and elderly patients with a reduction in cardiopulmonary function. There were differences in the time course of improvement between cardiac remodeling and exercise capacity in those patients. (J Interven Cardiol 2013;26:195–199)

The aim of this study was to demonstrate the feasibility and usefulness of addition of the right parasternal approach to the conventional left parasternal and apical approaches using two-dimensional (2D) and three-dimensional (3D) transthoracic echocardiography (TTE) for morphologic evaluation in cases of transcatheter closure of atrial septal defects (ASDs).In 112 consecutive patients with ASDs, the morphology of the defects was evaluated for transcatheter closure in the right parasternal view in addition to the conventional left views using 2D and 3D TTE. Measurements of the maximal ASD diameter and detection of deficient rim obtained on 2D TTE were compared with those obtained by 2D transesophageal echocardiography. The shapes and locations of ASDs visualized by 3D TTE were compared with those visualized by 3D transesophageal echocardiography.In 88 patients (80.0%), optimal images from the right parasternal approach for morphologic evaluation of ASDs were obtained. Although there was a significant difference in maximal ASD diameter obtained only in the conventional left approach compared with transesophageal echocardiographic measurements (P.05), when the right parasternal approach was applied, a significant difference was not found (P = .18), and the diagnostic concordance of the rim deficiency was improved from 85.2% to 90.9%. Three-dimensional TTE from the right parasternal approach improved visualization of the shape and location of ASDs from 65.5% to 74.5%.Additional use of the right parasternal approach enables detailed morphologic evaluation for transcatheter closure of ASDs. In patients with suboptimal images on 3D TTE in the left conventional approach, additional 3D TTE in the right parasternal approach can improve the feasibility of obtaining optimal 3D images to evaluate the shapes and locations of ASDs.

Objectives: To evaluate the efficacy and safety of transcatheter closure of atrial septal defects (ASD) in patients over 70 years of age. Background: Transcatheter closure of ASD is an established procedure in children and young adults, but the benefits of this procedure in geriatric patients are still unclear. Methods: Between 2005 and 2010, 430 patients with ASD underwent transcatheter closure in our hospital. Among those patients, 30 consecutive patients older than 70 years of age were prospectively evaluated. Results: Mean age at procedure was 75.8 ± 3.8 years (range: 70–85 years). Mean Qp/Qs was 2.4 ± 0.7 and mean ASD diameter was 20.3 ± 6.4 mm. Nine patients (30%) had a history of hospitalization due to heart failure. ASD closure was successfully performed in 28 patients (93%) without significant complications. During the follow-up period (mean period of 19.1 ± 11.3 months), New York Heart Association (NYHA) functional class was significantly improved in 20 patients (74%). Significant improvements of plasma BNP level, resting heart rate, and systolic pulmonary artery pressure were also observed. Improvement of tricuspid regurgitation was observed in 11 of 17 patients with moderate or severe regurgitation during the follow-up period. Conversely, worsening of mitral regurgitation was observed in 10 of the 27 patients. Conclusion: Transcatheter closure of ASD in geriatric patients can be performed safely. This procedure contributes to significant improvement of symptoms and positive cardiac remodeling. Long-term follow-up is mandatory, especially for patients with mitral regurgitation. © 2012 Wiley Periodicals, Inc.

Nowadays transcatheter closure has become the standard treatment for an atrial septal defect (ASD). Since morphologic variation of ASD is common, imaging modalities with high diagnostic ability continue to be required. Meanwhile, experts are required to visualize high-quality images with advanced imaging modalities. Echocardiography plays a pivotal role in patient selection for treatment, recently introduced 3D echocardiography is a promising modality to provide comprehensible en face images of ASD, especially in patients with a complex-shaped ASD. In addition, cardiac MRI and computed tomography can provide complementary information. Transesophageal echocardiography and intracardiac echocardiography can provide images of excellent quality for guidance of the procedure. In this review, we discuss the role of imaging for transcatheter ASD closure, focusing on echocardiography.

Coronary sinus defect is a rare type of atrial septal defect. We report two patients who had a coronary sinus atrial septal defect without persistent left superior caval vein, where the orifice of the coronary sinus was closed using the Amplatzer Septal Occluder. The procedure was successful, without any complications including conduction disturbance.

Dental caries in early childhood is a significant public health problem, among which nursing caries is known to be caused by inappropriate nursing habits. The aim of the present study was to investigate lifestyle factors related to nursing caries. We examined 2,506 Japanese children aged 18 months, as a part of public health examinations conducted by the Municipal Public Health Center in 2008. Questionnaires were also administered to their guardians, which focused on nutritional and dental health conditions. Statistical analyses were then performed to determine significant nutritional and dental health factors associated with nursing caries. There were 117 children (4.7% of total) identified with dental caries, of whom 18 (0.7% of total cohort, 15.3% of children with dental caries) were designated as the nursing caries group. Statistical analyses revealed that breastfeeding was the most important factor as compared to children without nursing caries ( P =0.0002; odds ratio, 6.373). Our results showed that inappropriate breastfeeding is one of the most important factors related to both onset and exacerbation of nursing caries, and conclude that parents should be informed of appropriate breastfeeding practices by dentists for their prevention.

Neurotrophin receptor p75 (p75NTR) knockout mice (p75(−/−) mice) provide a good animal model of progressive-onset hearing loss.1 Cell loss of the spiral ganglion neurons (SGNs) and hair cell degeneration at the basal turn of the cochlea are seen in p75(−/−) mice from 3 months of age. Furthermore, from 3 to 6 months of age, the hearing thresholds of p75(−/−) mice are gradually raised; and after 6 months of age, the mice mostly exhibit hearing loss.1 Several previous reports have indicated that electroacupuncture (EA) stimulation may improve subjective symptoms of tinnitus or hearing loss.2 ,3 However, the molecular mechanisms underlying the therapeutic effect of EA stimulation for hearing loss remain unclear. Thus, to determine whether EA stimulation is useful for the prevention of hearing loss, we used a p75(−/−) mouse model of progressive-onset hearing loss. The Ting Gong (SI19; Small Intestine 19) and the Yifeng (TE17; Triple Energiser meridian 17) are …

Background The aim of this study was to demonstrate the utility of real-time three-dimensional (3D) transesophageal echocardiography (RT3D-TEE) using a matrix array 3D transesophageal echocardiographic probe for morphologic evaluation and guidance of transcatheter closure of atrial septal defects (ASDs). Methods Forty-eight consecutive patients scheduled for the intervention were included. Two-dimensional (2D) transesophageal echocardiography (2D-TEE) and RT3D-TEE were performed before and during the procedures. Measurements of maximal ASD diameter and surrounding rims obtained on RT3D-TEE were compared with those obtained on 2D-TEE. Results In 46 patients (96%), optimal 3D images for the morphologic evaluation of ASDs were obtained. RT3D-TEE facilitated the evaluation of ASD morphology and surrounding rims and was able to provide intraprocedural information clearly. A Bland-Altman plot showed a mean maximal diameter difference of −0.12 mm between the means (95% limits of agreement, −2.2 to 2.5 mm). Conclusion RT3D-TEE is a clinically useful, complementary option to 2D-TEE for evaluation of ASD morphology and for interventional guidance.

The influence of deficient rims surrounding atrial septal defects (ASDs) in patients undergoing transcatheter closure has yet to be clarified. The aim of this study was to assess the influence of a deficient surrounding rim on the procedural success and clinical outcome of transcatheter ASD closure using an Amplatzer septal occluder.A total of 474 patients (mean age, 46 ± 22 years) with ostium secundum ASDs measuring ≤40 mm in diameter who had undergone attempted transcatheter closure using Amplatzer septal occluders from September 2007 to August 2013 were assessed. A comprehensive transesophageal echocardiographic examination was done to assess the morphologic characteristics of the defects in all patients. Subjects were classified into three groups by the extent and location of rim deficiency (5 mm): patients without deficient rims (sufficient group, n = 101), patients with single deficient rims, (single group, n = 338), and patients with multiple rim deficiencies (multiple group, n = 35).There was a significant difference in the maximal defect diameter among the sufficient, single, and multiple groups (15 ± 6, 18 ± 6, and 29 ± 7 mm, respectively, P .001). Transcatheter closure was successfully accomplished in 463 patients (98%). The prevalence of procedural success differed significantly among the sufficient, single, and multiple groups (100%, 98%, and 86%, respectively, P .001). There was no significant difference in the occurrence of cardiovascular events among the three groups during a mean follow-up period of 25 ± 19 months (P = .926, log-rank test).In patients with ASDs with multiple rim deficiencies as determined by transesophageal echocardiography, successful transcatheter ASD closure using Amplatzer septal occluders is more difficult to accomplish. However, if closure is successful, rim deficiencies rarely affect intermediate-term outcomes.

We studied on various p-electrode patterns to solve current crowding problem in AlGaN-based deep-ultraviolet light-emitting diode. Simulation results of optimized p-electrode pattern showed a uniform current density distribution and improved performance of light output power.

Light extraction efficiency (LEE) in deep-ultraviolet light emitting diodes with AlN substrate was investigated using Ray Tracing method. The results showed that LEE was dramatically improved by optimizing the sidewalls angle and AlN thickness.

We assessed right ventricular (RV) geometric remodeling quantitatively in patients with chronic pulmonary hypertension (PH) secondary to left-sided heart disease using real-time 3-dimensional echocardiography by comparing segmental and total volumes to that in normal subjects. The comparison result revealed that RV geometric remodeling in the PH group mainly occurred at the basal, mid-basal, and mid-segments. Total RV end-diastolic and end-systolic volumes in the PH group were significantly larger than that in normal subjects.

Balloon angioplasty of a bifurcation lesion is associated with lower rates of success and higher rates of complications than such treatment of lesions of most other morphologies. To date, the best device or procedure for bifurcation lesions has not been determined. The aim of this study was to compare the immediate and 3-month follow-up outcome of cutting balloon angioplasty (CBA) versus conventional balloon angioplasty (PTCA) for the treatment of bifurcation lesions. We treated 87 consecutive bifurcation lesions with CBA (n = 50) or PTCA (n = 37). Paired angiograms were analyzed by quantitative angiography, and angiographic follow-up was achieved for 93% of the lesions. The procedural success was 92% in the CBA group and 76% in the PTCA group (P < 0.05). Major in-hospital complications occurred in two lesions in the CBA group and six in the PTCA group (P = 0.05). The incidence of bail-out stenting in the CBA group was lower than in the conventional PTCA (8% vs 24%, P < 0.05). At the 3-month follow-up, the restenosis rate was 40% in the CBA group versus 67% in the PTCA group (P < 0.05). Clinical events during follow-up did not differ between the two groups. In conclusion, in comparison with PTCA, procedural success was greater and the restenosis rate lower with CBA. The results of this study support the use of the cutting balloon as optimal treatment for bifurcation lesions. (J Interven Cardiol 2004;17:1–7)

We thoroughly explored the physical origin of the efficiency decrease with increasing injection current and current crowding effect in 280 nm AlGaN-based flip-chip deep-ultraviolet (DUV) light-emitting diodes (LEDs). The current spreading length was experimentally determined to be much smaller in DUV LEDs than that in conventional InGaN-based visible LEDs. The severe self-heating caused by the low power conversion efficiency of DUV LEDs should be mainly responsible for the considerable decrease of efficiency when current crowding is present. The wall-plug efficiency of the DUV LEDs was markedly enhanced by using a well-designed p-electrode pattern to improve the current distribution.

High-power 265 nm deep-ultraviolet (DUV) AlGaN-based light-emitting diodes (LEDs) with large-area AlN nanophotonic light-extraction structures that were fabricated by a nanoimprint lithography process are presented. Each DUV-LED has a large active area (mesa size of ∼0.35 mm2) and a uniform current spreading design that allows high injection current operation. We have shown that these DUV-LEDs with their large-area nanoimprinted AlN nanophotonic structures exhibit wider near-field emitting areas, stronger far-field extracted light intensities, and an approximately 20-fold increase in output power when compared with a conventional flat-surface DUV-LED. A large-area nanoimprinted single-chip DUV-LED operating in the UV-C wavelength regime has demonstrated a record continuous-wave output power in excess of 150 mW for an injection current of 850 mA at a peak emission wavelength of 265 nm.

We present a case of an atrial septal defect (ASD) in a 59-year-old man with an indication for ASD closure who also had a history of chronic obstructive pulmonary disease. Because of his decreased respiratory function with multiple bullae in his lungs, the procedure was performed without general anesthesia under the guidance of fluoroscopy and two-dimensional (2D) transesophageal echocardiography (TEE) using a transesophageal echocardiographic microprobe (micro-TEE) (S8-3t; Philips Medical Systems, Andover, MA, USA). The micro-TEE probe was inserted into the esophagus smoothly and easily in the supine position without sedation. It revealed a deficient superior-anterior rim and adequate rims elsewhere, and the maximal diameter of ASD was measured to be 25 mm. Balloon sizing resulted in a stretched defect diameter of 29 mm using the stop-flow technique. A 30-mm AMPLATZER Septal Occluder (AGA Medical, Plymouth, MN, USA) was deployed. The micro-TEE demonstrated that both disks were on the appropriate sides of the interatrial septum and the device was not interfering with surround cardiac structures. Residual shunt flow was not detected with color Doppler. The device was released successfully without any complications. Recently introduced multiplane micro-TEE can provide adequate information about a large ASD with a less invasive procedure in adult patients. Micro-TEE has a potential to become a novel imaging option for interventions of the interatrial septum.

Oxygen-regulated protein 150 kD (ORP150) is a novel endoplasmic-reticulum-associated chaperone induced by hypoxia/ischemia. Although ORP150 was sparingly upregulated in neurons from human brain undergoing ischemic stress, there was robust induction in astrocytes. Cultured neurons overexpressing ORP150 were resistant to hypoxemic stress, whereas astrocytes with inhibited ORP150 expression were more vulnerable. Mice with targeted neuronal overexpression of ORP150 had smaller strokes compared with controls. Neurons with increased ORP150 demonstrated suppressed caspase-3-like activity and enhanced brain-derived neurotrophic factor (BDNF) under hypoxia signaling. These data indicate that ORP150 is an integral participant in ischemic cytoprotective pathways.

Platypnea-orthodeoxia is a rare condition characterized by dyspnea and oxygen desaturation induced by the upright position and relieved by recumbency. The most common cause of this syndrome is right-to-left shunt through interatrial communications such as patent foramen ovale (PFO) or atrial septal defect (ASD). In addition, this syndrome can be caused by other extracardiac components, including pulmonary emphysema, pericardial disease, and prominent Eustachian valve. We experienced 3 cases of this syndrome, including 1 patient with PFO and 2 patients with ASD. Computer tomography imaging revealed aortic elongation and compression of the right atrium by ascending aorta in all of 3 patients. Transcatheter closure of PFO or ASD was successfully performed in all patients, including immediate improvements of symptoms and oxygen saturation without any complications.

The current crowding is an especially severe issue in AlGaN-based deep-ultraviolet (DUV) light-emitting diodes (LEDs) because of the low conductivity of the n-AlGaN cladding layer that has a high Al fraction. We theoretically investigated the improvement in internal quantum efficiency and total resistances in DUV-LEDs with an emission wavelength of 265 nm by a well-designed p-electrode geometry to produce uniform current spreading. As a result, the wall-plug efficiency was enhanced by a factor of 60% at an injection current of 350 mA in the designed uniform-current-spreading p-electrode LED when compared with an LED with a conventional cross-bar p-electrode pattern.

Impaired exercise capacity has been found in patients with diastolic dysfunction with preserved systolic function. Although conventional transthoracic echocardiography (TTE) provides useful clinical information about systolic and diastolic cardiac function, its capability to evaluate exercise capacity has been controversial. The inertia force of late systolic aortic flow is known to have a tight relationship with left ventricular (LV) performance during the period from near end-systole to isovolumic relaxation. The inertia force and the time constant of LV pressure decay during isovolumic relaxation can be estimated noninvasively using the second peak (W(2)) of wave intensity (WI), which is measured with an echo-Doppler system. We sought to determine whether W(2) is associated with exercise capacity in patients with chronic heart failure with normal ejection fraction (HFNEF) and to compare its ability to predict exercise capacity with parameters obtained by conventional TTE including tissue Doppler imaging. Sixteen consecutive patients with chronic HFNEF were enrolled in this study. Wave intensity was obtained with a color Doppler system for measurement of blood velocity combined with an echo-tracking system for detecting changes in vessel diameter. Concerning conventional TTE, we measured LV ejection fraction (EF), peak velocities of early (E) and late (A) mitral inflow using pulse-wave Doppler, and early (Ea) and late (Aa) diastolic velocities using tissue Doppler imaging. Left ventricular EF, E/A ratio, Ea, and E/Ea ratio did not correlate with exercise capacity, whereas W(2) significantly correlated with peak VO(2) (r = 0.54, p = 0.03), VE/VCO(2) slope (r = -0.53, p = 0.03), and ΔVO(2)/ΔWR (r = 0.56, p = 0.02). W(2) was associated with exercise capacity in patients with chronic HFNEF. In conclusion, W(2) is considered to be clinically more useful than conventional TTE indices for evaluating exercise capacity in patients with chronic HFNEF.

A recent study has shown that cryptogenic stroke can occur even in patients with small or insignificant atrial septal defects (ASD). However, clinical experience in this field is still limited in Japan, also the efficacy and safety of catheter closure of such defects have not been identified. To evaluate the efficacy and safety of catheter closure of interatrial communication in patients with cryptogenic stroke, 13 patients who were diagnosed with cerebrovascular events due to cryptogenic embolism were included in this study. Mean age at procedure was 43 ± 15 (range 17–68) years. In all patients, the presence of spontaneous or provoked interatrial right-to-left shunts was demonstrated by transesophageal contrast echocardiography. Mean defect size evaluated by the balloon sizing technique was 9.2 ± 2.8 mm, and mean size of the Amplatzer Septal Occluder deployed was 9.5 ± 2.8 mm. Devices were successfully deployed in all patients, though one device migrated into the descending aorta was retrieved by a snare catheter. Complete closure was detected by transesophageal contrast echocardiography at 12 months after the procedure was in 11 (85%) of the 13 patients. During the follow-up period (30.1 ± 9.4 months), no recurrent thromboembolic event was observed. Catheter closure of interatrial right-to-left communications can be safely performed. This procedure may contribute to reduction or prevention of recurrent neurological events in this patient population.

Atrial fibrillation (AF) often occurs in Brugada syndrome (BrS), and BrS patients with spontaneous AF often experience ventricular fibrillation (VF) attacks. Atrial vulnerability providing a substrate for AF is known to be enhanced in BrS, but there are no data on atrial structural attributes.The objective of this study was to assess atrial electrophysiological and structural characteristics in BrS and their relationships with gene mutations.We studied 57 patients with BrS. Intra-atrial conduction time (CT) was defined as the interval from the stimulus at the high right atrium to atrial deflection at the distal portion of the coronary sinus. Left atrial volume index (LAVI) was measured by the modified Simpson method at left ventricular end-systole using echocardiography. SCN5A mutations were analyzed in all patients.In patients with documented VF, spontaneous AF frequently occurred and prolonged CT and increased LAVI were observed compared with those in patients without VF (all P.05; LAVI: 22 +/- 5 vs. 32 +/- 7 ml/m(2)). Even among patients without AF, CT and LAVI were still increased in patients with VF (all P.05; LAVI: 22 +/- 5 vs. 29 +/- 5 ml/m(2)). The presence of SCN5A mutation was associated with prolonged CT (P.05) and increased LAVI (P.01), but not with arrhythmic episodes.Both atrial vulnerability and structural remodeling are enhanced in high-risk patients with BrS, even in those without AF. These morphological characteristics suggest that BrS is a form of genetic myocardial disease.

Objectives: The aim of this study is to evaluate the feasibility and efficacy of device closure of atrial septal defect (ASD) in elderly patients with permanent atrial fibrillation. Background: Little is known about the feasibility of device closure of ASD in those patients. Methods: Nine consecutive patients (mean age 68.1 years) with permanent atrial fibrillation (>1 year persistent) underwent catheter closure using the Amplatzer septal occluder. Transthoracic echocardiography and plasma B-type natriuretic peptide (BNP) level were assessed before and at 24 hours; and 1, 3, and >6 months after the closure. Before the procedure, appropriate dose of warfarin was used in all, diuretics was used in 8/9. Same amount of medications were continued after the procedure. Results: ASD could be closed in all (mean device size 27.3 mm) without hemodynamic and thromboembolic complications. New York Heart Association (NYHA) functional classification was significantly improved in all patients after device closure. No hemodynamic and thromboembolic complications were observed during the follow-up period (mean 10.6 months). Although permanent atrial fibrillation did not change in all after the procedure, resting heart rate decreased from 76.2 ± 16.0 to 68.3 ± 13.2 beats/min (P = 0.015). There was statistically significant improvement in right ventricular/left ventricular diameter ratio (1.08 ± 0.16 to 0.73 ± 0.10, P = 0.008) and plasma BNP level (183.7 ± 90.5 to 94.6 ± 47.4 pg/mL, P = 0.008) after >6 months device closure. Conclusions: Even in the patients complicated with permanent fibrillation, transcatheter closure of ASD can contribute to symptomatic improvement as well as cardiac geometric remodeling. © 2009 Wiley-Liss, Inc.

Background: Wave intensity (WI) is a new hemodynamic index that provides information about the dynamic behavior of the heart and the vascular system and their interaction. WI can be defined at any site in the circulatory system and provide a great deal of information. However, the clinical usefulness of the second peak of WI, which is related to the ability of the left ventricle to activity stop aortic blood flow, has not been fully reported. In previous study, the magnitude of W2 was related to the inertia force of late systolic aortic flow. Also, the higher augmented inertia force, which was calculated with cardiac catheterization, was associated with greater exercise capacity. Then, we hypothesize that WI is correlated to exercise capacity. In this study, we investigated whether WI and the echocardiographic parameters would be correlated with exercise capacity. Methods: A total of 24 patients of heart disease were enrolled. WI was obtained at the right carotid artery using a color Doppler system for blood velocity measurement combined with an echo-tracking method for detecting vessel diameter changes. As echocardiographic parameters, we analyzed ejection fraction (EF), the early (E) and late (A) diastolic mitral velocities, and early (Ea) and late (Aa) diastolic velocities measured using Tissue Doppler imaging. We evaluated exercise capacity (peak VO2, VE/VCO2, and AT). We used Pearson’s correlation analysis for statistics. Results: EF, the E/A ratio, and the E/Ea ratio were not correlated to exercise capacity. However, the second peak of WI was significant correlated to the peak VO2 (r=0.50, p

Objectives: To evaluate acute cardiac remodeling after transcatheter closure of atrial septal defect (ASD) in adult patients. Background: In adult patients with ASD, longer periods of cardiac adaptation should be expected after the procedure due to long-standing RV volume overload and subsequent changes in the pulmonary vasculature. There are limited reports about this remodeling in adult patients. Methods: We prospectively enrolled 17 adults (mean age 58.4 ± 17.3 years) who underwent successful transcatheter closure of their ASDs from August 2005 to July 2006. We performed routine transthoracic echocardiographic studies, including LV and RV myocardial performance indices, or Tei indices, and plasma brain natriuretic peptide (BNP) sampling before closure of the ASD, and 1 day, 1 month, and 3 months after closure. Results: We found (1) LV end diastolic diameter increased, and RVEDD decreased markedly after the closure; (2) differences existed in LV and RV adaptation. While LV Tei index improved soon after the procedure, RV Tei index worsened until 1 month after the procedure, then recovered by the 3 month follow-up visit; and (3) BNP elevated 1 day after closure of the ASD and declined by the 1-month follow-up visit. Conclusion: “Shrinkage” of the RV and “expansion” of the LV occurred soon after the procedure, even in elderly patients. Device closure of ASDs caused rapid improvement of LV function, but RV function underwent transient deterioration, probably due to delayed changes in RV ventricular mass in the face of acute volume reduction in this aged cohort. © 2007 Wiley-Liss, Inc.

Objective We sought to evaluate improvement of flow capacity in a left internal thoracic artery graft by means of pressure measurement. Methods Eighteen patients who received a left internal thoracic artery graft to the left anterior descending coronary artery were studied. Angiography and pressure measurement at the proximal and distal portions of the left internal thoracic artery graft during maximal hyperemia with a pressure guide wire were performed at 1 month (early study) and 6 months (late study) after surgical intervention. Results There are no significant differences between the early and late studies in resting mean aortic pressure, left ventricular end-diastolic pressure, left ventricular ejection fraction, and percentage diameter stenosis of the recipient left anterior descending coronary artery. There was no stenosis in the anastomosis site of the left internal thoracic artery graft and the distal left anterior descending coronary artery, as determined by means of angiography, in the early and late studies. The mean diameter of the distal left internal thoracic artery graft was significantly increased in the late study (1.6 ± 0.2 vs. 1.8 ± 0.2 mm, P = .011). There was a significant difference between the early and late studies in the pressure gradient through the graft (15 ± 4 vs 13 ± 3 mm Hg, P = .036). The ratio of distal to proximal pressure within the left internal thoracic artery graft in the late study was significantly increased from that in the early study (0.80 ± 0.04 to 0.84 ± 0.03, P = .0003). Conclusions The pressure ratio within the left internal thoracic artery graft became higher as the left internal thoracic artery graft adapted itself to the myocardial circulation. This finding might relate to decreasing the resistance of the left internal thoracic artery graft.

Brain natriuretic peptide (BNP) level has been used as a marker of left ventricular (LV) systolic dysfunction (LVSD), even though some patients with atherosclerosis have a high BNP level irrespective of LV function. In this study, we investigate whether augmentation index (AI), which is an index of wave reflection, is involved in increasing BNP level in hypertensive patients without LVSD. Sixty treated hypertensive patients were enrolled in this study. Radial AI (r-AI) was measured in all patients. The patients were classified into tertiles on the basis of r-AI to identify the characteristics of the patients with a high r-AI. BNP level was significantly higher in the patients classified into the highest tertile of r-AI. In echocardiography, e', which is index of left ventricular (LV) diastolic function, decreased and LV mass index (LVMI) increased gradually with r-AI, whereas there was no difference in LV ejection fraction (LVEF). r-AI significantly correlated with LVMI (r=0.35, p

Adequate septal rim is an important factor for device closure of atrial septal defect (ASD). As little is known about the procedural completion in ASD patients with multiple rim deficiencies, we aimed to evaluate the validity of device closure for these patients. Between September 2007 and May 2013

A 25-year-old male was admitted to hospital with a 3-day history of worsening faintness. The electrocardiogram showed complete atrioventricular block. Echocardiography showed generalized hypokinesis and prominent trabeculations ranged from the apex to the mid-ventricular lateral wall of the left ventricle as well. Furthermore, trabeculations in the left ventricle were seen in his sister and brother. Thus, isolated ventricular noncompaction (IVNC) was diagnosed and a permanent pacemaker was implanted. Common clinical symptoms of IVNC are heart failure, ventricular arrhythmias, and embolic events. This is the first reported adult case of IVNC disclosed by the presence of complete atrioventricular block.

A 36-year-old Japanese man was hospitalized with coughing and exertional dyspnea (NYHA class I). He was diagnosed as having congestive heart failure, and was treated with diuretics and a beta-adrenergic blocking agent. He responded well to the treatment and his symptoms completely disappeared within a few days. Based on his clinical, laboratory, and molecular genetic findings, he was diagnosed as having X-linked dilated cardiomyopathy (XLDCM). He was found to have a large deletion in the dystrophin gene, involving exons 45-55. This is the first report on a Japanese XLDCM patient with a mutation in the central hot-spot region of this gene.

A 29-year-old man was hospitalized because of dyspnea and palpitation. Electrocardiography demonstrated normal sinus rhythm and borderline right atrial enlargement. Twodimensional transthoracic echocardiography (2D-TTE) revealed a normal left ventricular systolic function. There was a paradoxical septal motion consistent with right ventricular volume overload (Fig. 1a). Although the right ventricle was mildly dilated, its systolic function was preserved. 2D-TTE revealed a large atrium without distinct interatrial septum (Fig. 1b). Left-to-right shunt flow was not detected clearly through the defect on color-flow Doppler imaging. Real-time three-dimensional echocardiography (RT3D-TTE) visualized a large defect of interatrial septum clearly (Fig. 2). The patient was referred for surgery. Only a tiny vestige of the interatrial septum could be confirmed with the naked eye, and the two atrioventricular valves were normal. The patch closure was performed successfully using a fresh autologous pericardial patch. Atrial septal defect (ASD) is a common congenital heart disease presenting in adulthood. Our patient showed a large secundum ASD like single atrium. It is sometimes difficult to distinguish a large secundum ASD from a single atrium. Levy et al. recommended that the term ‘‘single atrium’’ should be used to denote a condition comprising: (1) complete absence of the interatrial septum, (2) absence of malformation of the atrioventricular valves, and (3) absence of interventricular communication [1]. In our case, the morphological diagnosis was supposed to be a large secundum type atrial septal defect, because a small part of the interatrial septum was found. In this case, RT3D-TTE enhanced the understanding of the anatomy and spatial relationship between the defect and its adjacent structure. Previous study has shown the usefulness of RT3D-TTE for patient selection for surgical or transcatheter closure of atrial septal defects. It has been reported that RT3D-TTE allows accurate determination of the ASD location, ASD size, and surrounding tissue of the interatrial septum [2, 3]. Although our patient demonstrated a large part to be missing from the interatrial septum, RT3D-TTE could clearly visualize a large defect of the interatrial septum. RT3D-TTE provided additional, clinically relevant qualitative information for the evaluation of this patient with a large defect of the interatrial septum. N. Watanabe Y. Tanabe Division of Medical Support, Okayama University Hospital, Okayama, Japan

Transcatheter closure of atrial septal defects (ASDs) has become an accepted and reliable procedure. Although various complications have been recognized, tear of the atrial septal rim is a rare complication. We report a case of atrial septal rim tear that was diagnosed during the procedure by real-time three-dimensional transesophageal echocardiography (TEE). The device was successfully implanted 3 months after the initial intervention. RT3D TEE is more useful for displaying the entire shape of the defect and its spatial relationship (RT3D) with its neighboring structures compared with conventional two-dimensional echocardiography. By using both two-dimensional and RT3D TEE images, especially in cases with complicated ASD morphology, both the echocardiologist and interventionalist gain valuable information on the morphology of the ASD before and during the procedure.