Efficacy of Artificial Chordal Reconstruction for Idiopathic Severe Mitral Regurgitation Due To Chordal Rupture in Infancy.

Early surgical intervention is required for sudden onset, severe mitral regurgitation (MR) due to chordal rupture in infants with normal development younger than 1 year. The condition has been recognized as idiopathic. However, the surgical options in children are limited because of their size and somatic growth. We sought to examine the efficacy of mitral valve plasty by artificial chordal reconstruction for these infants in mid-to-long term. From August 2005 through June 2012, 8 consecutive patients aged 1-7 months underwent mitral valve plasty by chordal reconstruction using expanded polytetrafluoroethylene sutures for MR, owing to leaflet prolapse. The geometric parameters of the diameter of the mitral annulus (D1), the long axis of the left ventricular (LV) chamber (D2), and the length of the papillary muscle including the reconstructed chordae (D3) were measured, as well as MR grade (0-4) and LV end-diastolic dimension, at each time point. The parameters were compared with those in the control group that included Kawasaki disease patients without cardiac lesions and healthy children (n = 51). Mean follow-up period was 5.8 (2.8-9.6) years. Freedom from reoperation was 100%. MR grades were 3.9 ± 0.4 preoperatively, 2.4 ± 0.9 at discharge, and 1.4 ± 0.6 at the latest. Postoperative MR was improved within 1 year in 5 of 6 patients who had grade 2 or higher regurgitation. LV end-diastolic dimensions were 109% (% of normal), 113%, and 107% at discharge, 3, and 5 years, respectively. Geometric configuration indicated by the D1/D2 ratio did not significantly change with time. The length of the papillary muscle including reconstructed chordae (D3) strongly correlated with body surface area (r(2) = 0.65), which seemed to be equivalent to that in the control group. In conclusion, postoperative mitral valve function and geometry was preserved. This procedure with a low morbidity should be an option for pediatric patients with acute severe MR.

[Clinical Experience of Beating Heart Atrial Septostomy Using a Device for Coronary Artery Anastomosis Site Creator].

BACKGROUND: Intra-atrial communication was mandatory for several congenital cardiac diseases, such as pulmonary atresia with intact ventricular septum (PA/IVS), and either sided aortoventricular valve atresia. We assessed whether the new methods of atrial septal defect(ASD)creation was effective. METHODS: We experienced 4 cases of the surgical atrial septostomy performed under on-pump beating. We used a new device, a circular punch out defect creator. RESULTS: All cases were alive. The mean ASD diameter was enlarged from 4.37 mm to 5.55 mm and the mean ASD shunt flow was significantly decreased from 1.47 m/s to 1.11 m/s. CONCLUSIONS: We performed the surgical atrial septostomy using an aortic puncher under beating heart effectively and safely.

Efficacy and haemodynamic effects of vacuum-assisted closure for post-sternotomy mediastinitis in children.

OBJECTIVES: Post-sternotomy mediastinitis is a significant morbidity with controversial management. Vacuum-assisted closure (VAC) has been used to treat mediastinitis, with many reports documenting its efficacy and feasibility, particularly in adults. However, its use is not prevalent in the paediatric population because of concerns that it may deteriorate haemodynamics. This study aimed to evaluate outcomes and effects of VAC on the haemodynamics of paediatric patients with post-sternotomy mediastinitis. METHODS: Six patients were treated with VAC between April 2005 and March 2013. We retrospectively investigated their profiles, clinical outcomes and haemodynamic changes, including mean blood pressure (MBP), mean heart rate (MHR), urinary output, amount of diuretics and vasoactive-inotropic score (VIS), before and after VAC initiation. RESULTS: The median age and body weight of patients were 6.4 months and 4.5 kg, respectively. Three patients (50%) had single ventricular physiology. The median VAC duration was 12 days. One patient died of pulmonary venous obstruction after mediastinitis was cured. The average MBPs in every 8-h period were examined, and there were no significant changes (P = 0.773); the average MHRs were examined in the same manner and they decreased significantly after initiation of VAC (P = 0.032). Only 2 patients required vasoactive agents. The VIS did not change in 1 patient and decreased in the other. The mean amount of diuretics administered and urinary output per body weight did not change significantly (P = 0.395 and 0.273, respectively). CONCLUSIONS: In conclusion, the haemodynamics of children were not significantly affected by the negative pressure of VAC, indicating that this therapy may be safe and effective for post-sternotomy mediastinitis, even in small children with complex cardiac anomalies.

Double-chambered right ventricle associated with infective endocarditis complication of the pulmonary valve: surgical management.

Double-chambered right ventricle (DCRV) is a rare congenital heart disease characterized by the presence of anomalous muscle bundles, which divide the right ventricle into two chambers: a high-pressure proximal chamber and a low-pressure distal chamber. Most DCRV patients are diagnosed and treated during childhood, and presentation in adulthood is not common. Many congenital heart diseases are often associated with other complications such as infective endocarditis (IE). Right-side endocarditis, which usually involves infection of the tricuspid valve, is uncommon, and endocarditis of the pulmonary valve is extremely rare. We report a 51-year-old woman with undiagnosed DCRV and ventricular septal defect associated with pulmonary valve endocarditis. The diagnostic evaluation and the surgical management are discussed.

The possible roles of mineralocorticoid receptor and 11beta-hydroxysteroid dehydrogenase type 2 in cardiac fibrosis in the spontaneously hypertensive rat.

In hypertension, aldosterone has been demonstrated to play a crucial role in cardiac fibrosis, which generally increases cardiac morbidity and death. However, few studies have reported the expression of the mineralocorticoid receptor (MR) and 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2) in the heart under hypertensive conditions. Therefore, in this study, spontaneously hypertensive rats (SHR) were examined to elucidate the possible actions of mineralocorticoids via binding to MR. Wister Kyoto Rat (WKY), SHR, stroke-prone SHR (SHRSP), and malignant SHRSP (M-SHRSP) were used. Total RNA was extracted from the left ventricle of these rats, and examined for the expression levels of MR, 11beta-HSD2 and Collagen types 1 and 3 using reverse transcription real-time quantitative polymerase chain reaction employing the Light Cycler Instrument. Blood pressure was significantly different among each group. The mean mRNA levels for MR, 11beta-HSD2 and Collagen types 1 and 3 in M-SHRSP were found to be significantly increased compared to those of WKY, whereas no significant differences in mRNA levels were detected among SHR and SHRSP. Findings from the present study appear to demonstrate that MR and 11beta-HSD2 mRNA significantly rise in the left ventricle of M-SHRSP and increase of these mRNA is one of the cause of cardiac fibrosis.