Most long QT syndrome patients are associated with genetic mutations. We aimed to investigate the clinical and biochemical characteristics and look for genotype-based preventive implications in Chinese long QT syndrome patients.

We identified two missense mutations of the KCNQ1 gene in two independent Chinese families, including a previously reported mutation R380S in the C-terminus and a novel mutation W305L in the P-loop domain of the Kv7.1 channel, respectively. The proband with R380S was an 11-year-old girl who suffered a prolonged corrected QT interval of 660 ms, recurrent syncope, and sudden cardiac death, whose father was an asymptomatic carrier. The mutation W305L was detected in a 36-year-old woman with long QT syndrome and her immediate family members including the proband’s younger sister with an unexplained syncope, her son, and her elder daughter without symptoms. Metoprolol appeared to be effective in preventing arrhythmias and syncope in long QT syndrome patients with mutation W305L. Both R380S and W305L mutations led to “loss-of-function” of the Kv7.1 channel accounting for the clinical phenotypes.

We first show two missense KCNQ1 mutations – R380S and W305L – in Chinese long QT syndrome patients, resulting in the loss of protein function. Mutation W305L in the P-loop domain of the Kv7.1 may derive a pronounced benefit from β-blocker therapy in symptomatic long QT syndrome patients, whereas mutation R380S located in the C-terminus may be associated with a high risk of sudden cardiac death.

Surgical repair for cardiac lesions has rarely been offered to patients with trisomy 18 because of their very short lifespans. We investigated the effectiveness of cardiac surgery in patients with trisomy 18.

We performed a retrospective analysis of 20 consecutive patients with trisomy 18 and congenital cardiac anomalies who were evaluated between August, 2003 and July, 2013. All patients developed respiratory or cardiac failure due to excessive pulmonary blood flow. Patients were divided into two subgroups: one treated surgically (surgical group, n=10) and one treated without surgery (conservative group, n=10), primarily to compare the duration of survival between the groups.

All the patients in the surgical group underwent cardiac surgery with pulmonary artery banding, including patent ductus arteriosus ligation in nine patients and coarctation repair in one. The duration of survival was significantly longer in the surgical group than in the conservative group (495.4±512.6 versus 93.1±76.2 days, respectively; p=0.03). A Cox proportional hazard model found cardiac surgery to be a significant predictor of survival time (risk ratio of 0.12, 95% confidence interval 0.016–0.63; p=0.01).

Cardiac surgery was effective in prolonging survival by managing high pulmonary blood flow; however, the indication for surgery should be carefully considered on a case-by-case basis, because the risk of sudden death remains even after surgery. Patients’ families should be provided with sufficient information to make decisions that will optimise the quality of life for both patients and their families.

Most idiopathic right ventricular tachycardias originate from the outflow tract. We present a case series of idiopathic incessant ventricular tachycardia arising from unusual sites of the right ventricle in children, which were well resolved by catheter ablation.

A retrospective review was performed of all three patients who underwent ablation of idiopathic ventricular tachycardia below the level of the right ventricular outflow tract using three-dimensional mapping in our institute.

All three patients presented with tachycardia-induced cardiomyopathy due to incessant ventricular tachycardia on first admission. The sites of successful ablation were at the proximal right bundle branch, distal right bundle branch, and apex of the right ventricle, respectively. No complications occurred, and there has been no recurrence of ventricular tachycardia after the final ablation at an average follow-up period of 9 months. All three patients have achieved normalisation of left ventricular size and systolic function.

Incessant idiopathic ventricular tachycardia originating from unusual sites of the right ventricle in children, resulting in significant symptoms and impaired ventricular function, can be successfully treated with catheter ablation.

The objective of this study was to evaluate the impact and efficacy of pulse oximetry screening for CHD in a level-two neonatal unit without on-site access to paediatric echocardiography.

All neonatal unit admissions between 1 September, 2011 and 31 August, 2013 were reviewed to determine the outcomes of newborns identified by pulse oximetry screening. Record linkage with the National Congenital Heart Disease Audit allowed follow-up of newborns with a negative screening result.

There were 11,233 live births during the study period, with 973 neonatal unit admissions unrelated to pulse oximetry screening. From the remaining screening population of 10,260 newborns, 23 were admitted on the basis of a screen-positive result; three of the 23 patients went on to have urgent echocardiograms, and two were found to have critical CHD. In the 21 newborns without critical CHD, an alternative diagnosis was made in 16 cases. Record linkage with the National Congenital Heart Disease Audit indicated that no newborns born in the hospital during the study period received surgery for critical CHD following negative screening. The estimated sensitivity of screening was 100% (95% confidence interval 15.81–100%) and specificity was 99.80% (95% confidence interval 99.69–99.87%), with a false-positive rate of 0.20% (95% confidence interval 0.13–0.31%).

The introduction of pulse oximetry screening to a hospital where paediatric echocardiography services are not available is practical, results in very few referrals to the regional paediatric cardiology centre, and detects cases of CHD that would otherwise go undiagnosed. Record linkage with a national CHD database provides a straightforward method for tracking cases of CHD that may have been missed by screening.

The aim of the present study was to determine the outcomes of using the Valeo stent (Bard Peripheral Vascular, Tempe, Arizona, United States of America) in small children with CHD.

Stenting vascular stenoses is safe and effective in adults and older children with CHD but is limited in smaller children. The design of the Valeo stent addresses these limitations but has not been extensively described.

Bench testing was conducted to determine the maximum diameter of the stent, foreshortening, and side-cell diameter. A retrospective analysis of Valeo stents implanted between October, 2012 and October, 2014 was performed. Patient profile, pre-implant/post-implant catheterization data, and stent geometry were reviewed.

Bench testing: medium and large Valeo stents can be dilated up to 13 mm and 20 mm diameters, respectively. Side-cells are dilatable up to 12 mm. Valeo stents are of low profile – delivered through 6- or 7-Fr sheaths – and show minimal foreshortening. Retrospective analysis: a total of 81 stents were implanted in 61 patients with CHD. The median weight was 15.3 kg, and the median age was 58.9 months. Stents were implanted in the pulmonary artery, systemic vein, aorta, and pulmonary vein. Overall, mean vessel diameters increased from 4.1 to 7.7 mm (121.7%). There was effective mean gradient reduction: 3.7–0.5 mmHg (63%) in the venous systems, 28.2–12.5 mmHg (63.7%) in the pulmonary arteries, and 17.4–4 mmHg (77.1%) in the aorta. The mean stent foreshortening was 2.5%, and the mean recoil was 5.9%. Side-cells that crossed other vessels were dilated in four cases, and stents were re-mounted onto different-sized balloons in seven cases.

The features of the Valeo stent, such as low profile, large maximum diameter, open-cell design, minimal foreshortening, and recoil, make it suitable for treating vascular stenoses in small children with CHD.

Agreement between echocardiography and right heart catheterisation-derived right ventricular systolic pressure is modest in the adult heart failure population, but is unknown in the paediatric cardiomyopathy population.

All patients at a single centre from 2001 to 2012 with a diagnosis of cardiomyopathy who underwent echocardiography and catheterisation within 30 days were included in this study. The correlation between tricuspid regurgitation gradient and catheterisation-derived right ventricular systolic pressure and mean pulmonary artery pressure was determined. Agreement between echocardiography and catheterisation-derived right ventricular systolic pressure was assessed using Bland–Altman plots. Analysis was repeated for patients who underwent both procedures within 7 days. Haemodynamic data from those with poor agreement and good agreement between echocardiography and catheterisation were compared.

A total of 37 patients who underwent 48 catheterisation procedures were included in our study. The median age was 11.8 (0.1–20.6 years) with 22 males (58% total). There was a modest correlation (r=0.65) between echocardiography and catheterisation-derived right ventricular systolic pressure, but agreement was poor. Agreement between tricuspid regurgitation gradient and right ventricular systolic pressure showed wide 95% limits of agreement. There was a modest correlation between the tricuspid regurgitation gradient and mean pulmonary artery pressure (r=0.6). Shorter time interval between the two studies did not improve agreement. Those with poor agreement between echocardiography and catheterisation had higher right heart pressures, but this difference became insignificant after accounting for right atrial pressure.

Transthoracic echocardiography estimation of right ventricular systolic pressure shows modest correlation with right heart pressures, but has limited agreement and may underestimate the degree of pulmonary hypertension in paediatric cardiomyopathy patients.

The aim of this study was to evaluate the safety and efficacy of the Amplatzer Vascular Plug-II used for the closure of perimembranous ventricular septal defects.

There are no FDA-approved transcatheter devices for the closure of perimembranous ventricular septal defects. Several studies have reported on the use of various devices either off-label or under clinical trial protocols. However these reports have described significant adverse events including residual shunts, complete heart block, arrhythmia, and new valve regurgitations. Thus far, no study on the Amplatzer Vascular Plug-II has been reported.

We conducted a 4-year retrospective chart review from August, 2010 to August, 2014, of patients with perimembranous ventricular septal defects associated with ventricular septal aneurysm who underwent transcatheter closure using the Amplatzer Vascular Plug-II.

A total of 16 patients underwent Amplatzer Vascular Plug-II transcatheter closure of their perimembranous ventricular septal defects. The median age was 2.56 years (range: 0.5–27.3). Their median weight was 13.0 kg (range: 6.9–71.6). The left ventricular median defect size was 9.3 mm (range: 5.9–14.4). The right ventricular median defect size was 3.6 mm (range: 2.3–5.8). All the patients underwent successful device implantation with 83% of the patients having complete echocardiographic closure at the 1-year follow-up; however, one procedure was complicated by early device embolisation. The device was successfully retrieved and replaced with a larger device. There were no device-related outflow tract obstructions, rhythm abnormalities, or haemolysis.

Application of the Amplatzer Vascular Plug-II for closure of perimembranous ventricular septal defects appears to be a safe and effective treatment option. Prospective clinical trials and longer follow-up periods are warranted.