Constrictive pericarditis after surgical closure of atrial septal defect in a child.

Constrictive pericarditis following an open cardiac surgery for congenital heart disease is very rarely encountered in children. We report a case of constrictive pericarditis, diagnosed at 22 months after surgical closure of an atrial septal defect, in a 14-year-old boy who presented postpericardiotomy syndrome. Cardiac catheterization revealed uniformity of elevated diastolic pressures in all chambers, prominent x and y descents in the right atrial pressure tracing, and typical "dip and plateau" contour of ventricular end-diastolic pressures. Pericardiectomy improved the hemodynamic status of the patient. He remains symptom-free during the follow-up period of 12 months.     

Myocardial performance index after surgical correction of ventricular septal defects

Introduction

The myocardial performance index (MPI) has been described as a non-invasive Doppler measurement of ventricular function. The aim of this study was to assess MPI following surgical correction of ventricular septal defect (VSD) and to evaluate its impact on postoperative recovery.

Material and methods

This is a prospective study involving 30 children (16 girls and 14 boys) operated on for VSD (group I). The control group (group II) consisted of 30 healthy children (age and sex matched).

Results

We found that both the right and left ventricular (RV and LV) MPI correlated significantly with the ejection fraction (EF) (r = –0.49, p = 0.006, r = –0.51, p = 0.004, respectively). The LV EF and the LV FS were negatively correlated, while the left and right ventricular MPI was positively correlated with the: LVEDD (p = 0.000), the VSD size (p = 0.000), and the postoperative course of the patients in terms of the duration of ventilation (p = 0.000), the duration of use of inotropics (p = 0.000) and the duration of staying in the ICU (p = 0.000). By linear regression, the factors that correlated with the postoperative course of VSD surgery were the RV MPI pre-surgery, MPI 2 days after surgery and the ejection fraction (p = 0.000).

Conclusions

Myocardial performance index is a useful index for measurement of the left and right ventricular function. It correlates significantly with the ejection fraction, fractional shortening, VSD size, and the left ventricular size. It also significantly predicts the outcome of VSD surgery.     

Assessment of right atrial and right ventricular size in children after percutaneous closure of secundum atrial septal defect with Amplatzer septal occluder

Introduction

The aim of this study was to evaluate the right atrial (RA) and right ventricular (RV) size, and the speed of their normalization, in children after percutaneous closure of secundum atrial septal defect with the Amplatzer septal occluder.

Material and methods

The study group consisted of 42 children, aged 4.5 to 18.5 years. The following measurements (indexed to body surface area) were performed using 2D echocardiography: longitudinal, transverse axis and area of RA, RV inflow dimensions at one-third, and halfway between the tricuspid annulus and the apex (in the apical 4-chamber view), short axis and M-mode RV diastolic dimensions. All measurements were obtained 24 h and 1, 3 and 12 months after the procedure, then annually over 4 years of follow-up, and compared with the values obtained from the control groups.

Results

A significant decrease in all RA and RV values was observed after 24 h. Right ventricular transverse dimension normalized after 1 month, the RA longitudinal axis and area and the RV inflow dimensions after 3 months, and the RA transverse axis and M-mode RV diastolic dimension after 2 years, but the ratio of transverse to longitudinal RA axis remained significantly higher.

Conclusions

Right atrial and right ventricular measurements decrease rapidly during the first 24 h, and most of them normalize within a 3-month period. M-mode RV diastolic dimension does not capture the real RV changes. Amplatzer septal occluder closure of ASD influences the RA geometry, which is reflected by the higher transverse to longitudinal RA axis ratio.     

Alpha-cardiac actin mutations produce atrial septal defects

Atrial septal defect (ASD) is one of the most frequent congenital heart defects (CHDs) with a variable phenotypic effect depending on the size of the septal shunt. We identified two pedigrees comprising 20 members segregating isolated autosomal dominant secundum ASD. By genetic mapping, we identified the gene-encoding alpha-cardiac actin (ACTC1), which is essential for cardiac contraction, as the likely candidate. A mutation screen of the coding regions of ACTC1 revealed a founder mutation predicting an M123V substitution in affected individuals of both pedigrees. Functional analysis of ACTC1 with an M123V substitution shows a reduced affinity for myosin, but with retained actomyosin motor properties. We also screened 408 sporadic patients with CHDs and identified a case with ASD and a 17-bp deletion in ACTC1 predicting a non-functional protein. Morpholino (MO) knockdown of ACTC1 in chick embryos produces delayed looping and reduced atrial septa, supporting a developmental role for this protein. The combined results indicate, for the first time, that ACTC1 mutations or reduced ACTC1 levels may lead to ASD without signs of cardiomyopathy.     

儿童房间隔缺损封堵术前后血液动力学及心功能的研究

目的:评价儿童房间隔缺损(ASD)封堵术前后的血液动力学及左心功能改变。方法:应用Amplatzer封堵器成功施行经皮股静脉穿刺ASD封堵术患儿10例, 于术前、术后48h、3个月及6个月行超声心动图检查。左心室容积采用面积长度法计算;左心室几何构型采用偏心率及左心室长径/短径比值评价。结果:ASD封堵术后48h, 左心室舒张末期前后径、舒张末期容积增大、每搏量、射血分数及短轴缩短率增大, 左心室偏心率及长径/短径比值缩小(P＜0.05);左心室前负荷、收缩功能及几何构型在短、中期随访中持续改善。术后及短、中期随访中左心室晚期充盈分数, 差异无显著(P＞0.05)。结论:ASD封堵术不仅根治了先天性解剖畸形, 纠正了血液动力学异常, 也改善了左心室收缩功能及几何构型, 在短、中期随访中, 左心室功能及几何构型持续改善。     

经皮穿刺闭合房间隔缺损的应用解剖

目的为经皮穿刺闭合房间隔缺损提供相关的应用解剖资料。方法解剖测量50例(男29,女21)正常成年人心脏标本。结果卵圆窝长(20.9±5.4)mm,宽(14.3±3.7)mm。卵圆窝中点距冠状窦口中点(19.7±4.1)mm;距膜性房间隔(22.6±3.8)mm;距三尖瓣隔侧瓣中点(25.1±4.2)mm和距主动脉隆凸底部的中点(24.7±4.2)mm。卵圆窝中点距二尖瓣前瓣中点距离为(19.9±4.4)mm。卵圆窝缘的厚度在12、3、6和9点钟处分别是(4.1±0.7)、(3.2±0.7)、(2.3±0.5)和(3.3±0.7)mm。右上、下肺静脉汇入左心房的入口处水平距房间隔的距离分别为(8.2±2.2)mm和(12.4±3.8)mm。结论依据本文测量结果,经皮穿刺闭合房间隔缺损封堵器的厚度在5mm左右,且其弹性变化应适应房间隔厚度的变化为宜。     

Preoperative transcatheter closure of congenital muscular ventricular septal defects

BACKGROUND. Surgical repair of muscular ventricular septal defects, particularly those associated with complex heart lesions carries a higher risk of reoperation and death than the repair of membranous defects. Closing a muscular defect through an incision in the systemic ventricle may cause late ventricular dysfunction. In a collaborative approach to this problem, we undertook preoperative transcatheter closure of muscular ventricular septal defects remote from the atrioventricular and semilunar valves, followed by the surgical repair of associated conditions. METHODS. In 12 patients selected jointly by a cardiologist and a cardiac surgeon, we attempted preoperative transcatheter umbrella closure of 21 defects. Half the patients had associated complex heart lesions; the others had had pulmonary-artery banding to reduce the amount of left-to-right shunting. Half had severe ventricular septal deficiency. RESULTS. All 21 defects were successfully closed without major complications. Subsequent cardiac surgery for associated conditions in 11 of the 12 patients resulted in a mean pulmonary-to-systemic flow ratio of 1.1, indicating minimal residual left-to-right shunting; 1 patient awaited surgical repair. No deaths, reoperations, or late complications have occurred after a follow-up of 7 to 20 months. CONCLUSIONS. A collaborative approach using transcatheter closure followed by the surgical repair of associated cardiac lesions may decrease rates of operative mortality, reoperation, and left ventricular dysfunction in patients with muscular ventricular septal defects.