Hiromi Muta

Quantitation of the Global Right Ventricular Function in Children with Normal Heart and Congenital Heart Disease: A Right Ventricular Myocardial Performance Index

Abstract. Although the assessment of right ventricular (RV) function is important in the clinical management of children with congenital heart disease, available imaging techniques have been limited because of the complex geometry of the right ventricle. A new Doppler index combining systolic and diastolic time intervals (the Tei index) has been reported to be useful for the assessment of global RV function in adults. However, normal values in children, age-related changes, and the clinical utility of the Tei index with regard to congenital heart disease have not been demonstrated. The purpose of this study was to prospectively assess RV function in children with normal heart and congenital heart disease using the Tei index. The subjects included 150 healthy children and 43 patients with congenital heart disease (35 patients with atrial septal defects and 8 patients who had had a Senning operation). The index was defined as the sum of isovolumetric contraction time and isovolumetric relaxation time divided by ejection time and was measured from conventional RV outflow and inflow Doppler velocity profiles. The Tei index was not affected by age in healthy children (0.24 ± 0.04). There was a significant difference in index rating between patients who had had a Senning operation (0.58 ± 0.09) and healthy children (p < 0.01), but there was no significant difference between children with atrial septal defect (0.25 ± 0.13) and healthy children. The Tei index is a feasible approach to use when assessing global RV function in children with congential heart disease.

Sequential Follow-Up Results of Catheter Intervention for Coronary Artery Lesions After Kawasaki Disease Quantitative Coronary Artery Angiography and Intravascular Ultrasound Imaging Study

Background—The purpose of this study was to assess the sequential follow-up results of catheter intervention in Kawasaki disease by use of quantitative coronary angiography (QCA) and intravascular ultrasound imaging. Methods and Results—Catheter intervention was performed on 23 stenotic lesions in 22 patients (aged 2 to 24 years). Percutaneous balloon angioplasty (PBA) was performed in 4 patients, stent implantation in 7, percutaneous transluminal coronary rotational ablation (PTCRA) in 10, and a combination of PTCRA with stent implantation in 2. A total of 21 lesions (91%) were successfully dilated by catheter intervention without major or minor complications. One patient immediately underwent coronary artery bypass grafting (CABG) surgery because stent implantation failed to resolve his lesion. At 4 to 6 months after catheter intervention, 2 restenotic lesions (9%) were detected by QCA in 2 patients who had undergone PBA, and these patients subsequently underwent CABG surgery. In 6 months to 3 years after catheter intervention, no patients showed evidence of ischemic findings. At 3 to 4 years after catheter intervention, QCA and intravascular ultrasound studies were performed on 15 lesions in 14 patients. Two restenotic lesions (13%) were detected by QCA in 2 patients. One of the 2 had stent implantation and underwent CABG surgery, and the other had undergone PTCRA and underwent re-PTCRA. Thirteen patients demonstrated no ischemic findings at 3 to 8 years after catheter intervention. Conclusion—Catheter intervention for Kawasaki disease can be accomplished and can be effective in the short term, but the long-term efficacy should be verified by further study.

Sequential Evaluation of Left Ventricular Myocardial Performance in Children After Anthracycline Therapy

This study prospectively assessed subclinical cardiotoxicity in patients undergoing chemotherapy by using the Tei index combining systolic and diastolic time intervals. A significant difference in the Tei index was observed between patients who received a low dose and those who received a moderate to high dose of anthracycline antibiotic drugs. The Tei index is a sensitive, accurate, and easy approach for detecting subclinical anthracycline cardiotoxicity.

Quantitative evaluation of the changes in plasma concentrations of cardiac natriuretic peptide before and after transcatheter closure of atrial septal defect

The purpose of this study was to investigate the changes in plasma concentrations of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) in patients with atrial septal defect (ASD) during transcatheter closure of defects. The plasma concentrations of ANP and BNP were obtained from 14 patients with ASD at before closure, and at 5 min, 24 h, 1 mo and 3 mo after transcatheter ASD closure using an Amplatzer septal occluder. Ten healthy children aged 6–18 y were studied as controls. All ASDs were successfully closed. Compared with control values (mean ± SD, 17 ± 6.8 ng l‐1), ANP concentrations before closure were significantly elevated (24 ± 9.8 ng l‐1, p > 0.05). ANP concentrations increased significantly at 5 min after closure (34 ± 18 ng l‐1, p > 0.05) compared with preclosure concentrations. At 24 h after closure, the concentrations decreased to values not different from control values (19 ± 11 ng l‐1, p= ns). BNP levels before closure (19 ± 9.9 ng l‐1) were also elevated significantly compared with control values (12 ± 4.9 ng l‐1, p > 0.05). BNP concentrations increased significantly at 5 min after closure (23 ± 14 ng l‐1, p > 0.05) compared with preclosure concentrations. ANP values at 24 h were lower than at 5 min after closure, whereas BNP values were higher (32 ± 11ng l‐1, p > 0.05). As with ANP, the concentrations gradually decreased to values not different from control values at 3 mo after the procedure (12 ± 6.3 ng l‐1, p= ns).

Older Age Is a Risk Factor for the Development of Cardiovascular Sequelae in Kawasaki Disease

Objectives. To clarify the characteristics of Kawasaki disease (KD) in children 6 years and older and to determine whether age is a risk factor for cardiovascular abnormalities. Methods. Patients who had KD and were reported between 1999 and 2000 in the 16th nationwide survey of KD in Japan (n = 15 314) were analyzed. Patients who were aged 6 years or older (older group) were matched with patients who were aged 6 months to 3 years and were treated at the same hospital (younger groups). The total number of analyzed patients was 1498 (749 matched pairs). Results. The proportion of complete KD in the older group was similar to that in the younger group. Recurrent cases in the older group were significantly more common than those in the younger group (9% vs 2%). The proportion of patients who were treated with intravenous γ-globulin in the older group was significantly lower than that in the younger group (82% vs 87%). The proportion of older group patients who were treated with intravenous γ-globulin at or after 7 days of illness was significantly higher than that in the younger group (35% vs 14%). There was a higher prevalence of cardiovascular abnormalities in the older group than in the younger group (20% vs 15%). Multivariate logistic regression analysis showed that older age was an independent risk factor for cardiovascular sequelae (odds ratio: 1.58; 95% confidence interval: 1.01–2.46). Conclusions. In children older than 6 years, age is an independent risk factor for cardiovascular sequelae in KD.

Late Intravenous Immunoglobulin Treatment in Patients With Kawasaki Disease

OBJECTIVE: To evaluate the effectiveness of intravenous immunoglobulin (IVIG) treatment of Kawasaki disease ≥10 days after illness onset. METHODS: We selected patients initially treated with IVIG on days 11 to 20 in the database of the 20th nationwide survey in Japan. We then selected pair-matched control subjects of the same gender and age, who were initially treated with IVIG on days 4 to 8 with the same dose at the same institutions. We compared the proportions of additional treatments and coronary artery lesions (CALs) between the groups. We also compared fractional changes in various laboratory data before and after IVIG. Fractional change was defined as follows: (Y − X)/X, in which X represents the data before treatment and Y the data after treatment. RESULTS: One hundred fifty patients (75 pairs) were studied. The proportion of patients who received additional treatments among those given initial IVIG after days 10 was slightly lower than those treated earlier (12% vs 16%). The fractional changes in the white blood cell count, % neutrophils, and C-reactive protein were similar. Among all patients, the proportions of CALs during the convalescent phase were significantly higher in the late than in the early group (27% vs 1%). Among patients who had not developed CALs before initial treatment, the proportions with CALs during the acute phase were similar (8% vs 8%). CONCLUSIONS: IVIG treatment ≥10 days after illness onset achieves resolution of inflammation but was found to be insufficient for preventing CALs.

Percutaneous coronary intervention versus coronary artery bypass grafting for stenotic lesions after Kawasaki disease.

OBJECTIVE To compare the long-term efficacy of percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) for stenotic lesions after Kawasaki disease. STUDY DESIGN Questionnaires were sent to pediatricians in Japan in hospitals with 100 or more beds. A total of 1637 questionnaires were sent, and 1347 (82%) were returned. The primary endpoints of the study were the composite of deaths from any cause and the Q-wave myocardial infarction. The secondary endpoints were the repeat-revascularization for the target vessel. RESULTS A total of 67 patients underwent PCI and 81 patients underwent CABG. Although the rates of the primary endpoints did not differ between the groups (hazard ratio 1.35 [95% confidence interval 0.29 to 6.32], P=.7), the rate of the secondary endpoints in the PCI group was significantly higher than that in the CABG group (hazard ratio 2.23 [95% confidence interval 1.04 to 4.76], P=.04). The benefit with CABG for the secondary endpoints was notable in patients younger than 12 years old, and who had ischemic change. CONCLUSIONS PCI after Kawasaki disease resulted in a lower efficacy in comparison to CABG because of increased repeat-revascularization procedures.

Risk factors associated with the need for additional intravenous gamma-globulin therapy for Kawasaki disease.

AIM To investigate the characteristics of patients with Kawasaki disease who needed intravenous gamma-globulin (IVGG) re-treatment. METHODS Using the database of the 17th nationwide survey in Japan, a total 11,366 patients were identified and analysed (1,855 re-treatment patients and 9,511 responders). RESULTS Multivariate logistic regression analysis showed that male sex (odds ratio (OR) 1.26; 95% CI 1.14-1.40), complete cases (OR 1.39; 95% CI 1.07-1.80), recurrence (OR 1.47; 95% CI 1.15-1.88), IVGG treatment within 4 d of illness (OR 2.05; 95% CI 1.84-2.27), daily dose of initial IVGG less than 1,000 mg/Kg (OR 0.54; 95% CI 0.48-0.61), exanthema (OR 2.03; 95% CI 1.62-2.56), lips and oral lesions (OR 1.57; 95% CI 1.24-1.98), peripheral extremities changes (OR 1.85; 95% CI 1.54-2.22), and cervical lymphadenopathy (OR 1.89; 95% CI 1.66-2.16) were independent risk factors associated with the need for IVGG re-treatment. CONCLUSION Male sex, recurrence, and treatment with IVGG at a dose of 1,000 mg/d or less within 4 d of illness onset are independent risk factors associated with the need for IVGG re-treatment.

Quantitative Assessment of Severity of Ventricular Septal Defect by Three-Dimensional Reconstruction of Color Doppler–Imaged Vena Contracta and Flow Convergence Region

Background —The aim of the present study was to investigate the feasibility and potential value of the computer-controlled, 3D, echocardiographic reconstruction of the color Doppler–imaged vena contracta (CDVC) and the flow convergence (FC) region as a means of accurately and quantitatively estimating the severity of a ventricular septal defect (VSD). Methods and Results —We performed a 3D reconstruction of the CDVC and the FC region in 19 patients with an isolated VSD using an ultrasound system interfaced with a Tomtec computer. The variable asymmetric geometry of the CDVC and the FC region could be 3D-visualized in all patients. The 3D-measured areas of CDVC correlated well with volumetric measurements of the severity of VSD (r =0.97, P <0.001). Regression analysis between the shunt flow rate (calculated from the product of the area of CDVC and the continuous Doppler–derived velocity time integral) and the corresponding reference results (calculated by cardiac catheterization) demonstrated a close correlation (r =0.95, P <0.001). There was also a good correlation between shunt flow rates calculated using the conventional 2D, 1-axis measurement of the FC isovelocity surface area with the hemispheric assumption (r =0.95, P <0.001); shunt flow rates calculated using 3D, 3-axis measurements of the FC region (r =0.97, P <0.01); and reference results by cardiac catheterization. However, the 2D method substantially underestimated the actual shunt flow rate. Conclusions —The 3D reconstruction of the CDVC and the FC region may aid in quantifying the severity of VSD.

Serum alanine aminotransferase concentrations in patients with Kawasaki disease.

The distribution of serum alanine aminotransferase (ALT) in patients with Kawasaki disease (KD) was observed by using data collected from a nationwide survey in Japan. In comparison with normal values of 1 to 49 IU/l ALT, the odds ratio of cardiac disorders developing in the KD patients with an ALT of 200 IU/l or more was 1.91 (95% confidence interval, 1.44 to 2.54). The elevation of the ALT in KD patients is associated with the development of cardiac disorders.