Total anomalous pulmonary venous connection: impact of prenatal diagnosis.

OBJECTIVES: To investigate whether prenatal screening is effective in the detection of total anomalous pulmonary venous connection (TAPVC) and to identify common prenatal features. METHODS: This was a retrospective collaborative study involving 19 pediatric cardiac centers in the UK, Ireland and Sweden. Cases with TAPVC born between January 1, 1998 and December 31, 2004, and prenatally diagnosed cases whose estimated dates of delivery were within this time frame, were identified. Cases with functionally univentricular circulation or atrial isomerism were excluded. All available data and stored images were reviewed. RESULTS: Four-hundred and twenty-four cases with TAPVC were identified prenatally or postnatally, of whom eight (1.9%) had a prenatal diagnosis of TAPVC. Median gestational age at fetal diagnosis was 26 + 6 (range, 22 + 4 to 32 + 0) weeks. Six further fetuses with TAPVC had an abnormality diagnosed on prenatal ultrasound, but not the TAPVC. This included other congenital heart defects (four cases) and isolated pleural effusion (two cases). Seventeen (4.0%) of the 422 liveborn infants had a first-degree relative with congenital heart disease; and six of 17 had a sibling with TAPVC. Two died in utero. Of the liveborn infants diagnosed prenatally with TAPVC, none required urgent intervention for pulmonary venous obstruction and all were alive and well at a median of 2.3 (range, 1.0-7.0) years after surgical repair. CONCLUSION: Prenatal diagnosis of TAPVC is infrequent using current screening methods. Where there is a family history of TAPVC, specialized fetal echocardiography at 20 and 28 weeks' gestation may be indicated.

Predicting 22q11.2 deletion syndrome: a novel method using the routine full blood count.

BACKGROUND: 22q11.2 deletion syndrome is common affecting nearly 1 in 3000, including many with DiGeorge Syndrome and 5% of individuals with congenital heart disease. Diagnosis is important because affected patients have impaired immune function and may suffer high mortality rates if given non-irradiated blood products from graft versus host disease. Symptomatic hypocalcaemia may also occur. Our objective was to determine whether mean platelet volume (MPV), available from the routine full blood count, may be a useful and rapid indicator of 22q11.2 deletion. METHOD: A retrospective case control cohort study analysing MPV and 22q11.2 deletion status was performed in a paediatric population (n = 166) undergoing cardiac surgery between 1999 and 2005. RESULTS: Twenty children were 22q11.2 positive. The median MPV was significantly larger for the 22q11.2 positive patient group compared to the non-22q11.2 patients (10.9fL versus 8.6fL, p<0.001). The area under the curve of the receiver operating characteristics (ROC) curve of MPV was large enough (0.85) to enable the accurate prediction of 22q11.2 deletion using MPV. CONCLUSIONS: MPV is a useful screening test, involving no extra laboratory work, cost or patient discomfort. MPV>10fL is a positive predictor of the presence of 22q11.2 deletion in children with congenital heart disease (specificity 89.7%). This finding should aid rapid decision-making for ordering irradiated blood products to prevent potentially fatal transfusion-associated graft versus host disease. It will alert clinicians to monitor serum calcium levels closely to prevent hypocalcaemic seizures.

Pulmonary vein stenosis: the UK, Ireland and Sweden collaborative study.

OBJECTIVE: To describe clinical features, morphology, management and outcome of pulmonary vein stenosis (PVS) in childhood. DESIGN AND SETTING: Retrospective international collaborative study involving 19 paediatric cardiology centres in the UK, Ireland and Sweden. PATIENTS: Cases of PVS presenting between 1 January 1995 and 31 December 2004 were identified. Cases where pulmonary veins connected to a morphological left atrium were included. Functionally univentricular hearts and total anomalous pulmonary venous connection were excluded. All available data and imaging were reviewed. RESULTS: 58 cases were identified. In 22 cases (38%) there was premature delivery. 46 (79%) had associated cardiac lesions; 16 (28%) had undergone previous cardiac surgery before PVS diagnosis. 16 children (28%) had a syndrome or significant extracardiac abnormality. 36 presented with unilateral disease of which 86% was on the left. Where there was adequate sequential imaging, disease progression was shown with discrete stenosis leading to diffusely small pulmonary veins. Collateral vessels often developed. 13 patients had no intervention. Initial intervention was by catheter in 17 and surgery in 28. Overall 3-year survival was 49% (95% CI 35% to 63%) with patients undergoing initial surgical intervention having greater freedom from death or re-intervention (hazard ratio 0.44, 95% CI 0.2 to 0.99, p = 0.023). CONCLUSIONS: PVS is a complex disease of uncertain cause and frequently associated with prematurity. Early intervention may be indicated to deter irreversible secondary changes.

Pulmonary vein stenosis: initial experience with cutting balloon angioplasty.

OBJECTIVE: To determine the safety and effectiveness of cutting balloon angioplasty for pulmonary vein stenosis (PVS). DESIGN AND SETTING: Retrospective review of case notes and cardiac catheterisation data at the Royal Brompton Hospital. MAIN OUTCOME MEASURES: Diameter of pulmonary vein, tricuspid regurgitant jet velocity on echocardiogram, and percutaneous oxygen saturation before and after cutting balloon angioplasty. RESULTS: Three patients had congenital PVS and three had PVS associated with total anomalous pulmonary venous drainage. A total of 27 PVSs were treated during 12 catheterisation procedures. Median patient age at the time of procedure was 12.5 months (range 1.5-36 months) and weight was 7.1 kg (range 2.8-11.1 kg). Minimum pulmonary vein diameter increased significantly on angiography after cutting balloon angioplasty, from mean (SD) 2.3 (0.7) mm to 4.2 (1.9) mm, mean of differences 1.9 mm (95% confidence interval (CI) 0.9 to 2.9 mm, p = 0.0013). Mean (SD) oxygen saturation rose from 79.6 (12.9)% to 83.9 (9.0)%, mean of differences 4.3% (95% CI 0.7% to 8.0%, p = 0.0238). All children's symptoms improved subjectively. Tricuspid regurgitant jet velocity did not change significantly. The longest time interval before repeat intervention was six months. There were no acute deaths; one patient had a small pulmonary haemorrhage and developed a small aneurysm adjacent to the site of angioplasty. CONCLUSION: Cutting balloon angioplasty is safe in the palliation of PVS in children. It gives some acute relief but often needs to be repeated, as improvement is rarely sustained.

Can atrioventricular septal defects exist with intact septal structures?

The hallmark of an atrioventricular septal defect (AVSD) is a common atrioventricular junction, giving rise to a trileaflet left atrioventricular valve. AVSDs have the potential for interatrial shunting alone, interventricular shunting alone, or both. AVSDs without interatrial or interventricular communications have been identified at postmortem examination, but there are no reports of AVSDs with intact septal structures diagnosed in life. Six patients are described with AVSD and intact atrial and ventricular septa diagnosed echocardiographically. This report shows that AVSDs can exist without interatrial or interventricular communications and that the characteristic feature of this condition, the common atrioventricular junction with a trileaflet left atrioventricular valve, can be diagnosed in life by using cross sectional echocardiography. AVSDs with intact septal structures may be more common than previously described.

Development of Z-scores for fetal cardiac dimensions from echocardiography.

OBJECTIVES: Z-scores for cardiac dimensions are well established in postnatal life, but have yet to be developed for fetal cardiac dimensions. These would be of real advantage to the clinician in accurately quantifying size and growth of cardiac dimensions and to the researcher by allowing mathematical comparison of growth in differing subgroups of a disease. The purpose of this observational study, conducted at tertiary fetal medicine and cardiology units, was to produce formulae and nomograms allowing computation of Z-scores for fetal cardiac dimensions from knowledge of femur length (FL), biparietal diameter (BPD) or gestational age (GA) using fetal echocardiography. METHODS: Seventeen fetal cardiac dimensions were measured in 130 pregnant women with singleton fetuses of gestational age 15-39 weeks. Regression equations were derived relating all dimensions to FL, BPD and GA. From the calculations, formulae were then developed allowing fetal cardiac Z-score computation. RESULTS: The relationships between cardiac dimensions and FL, BPD or GA were described following natural log transformation. From this analysis, FL (taken as an expression of fetal size) had the highest correlation to fetal cardiac dimensions. From the developed nomograms, Z-scores of specific fetal cardiac structures could be estimated from knowledge of the FL, BPD or GA and echocardiographically derived measurements. CONCLUSIONS: This study allowed computation of Z-scores in fetal life for 17 cardiac dimensions from FL, BPD or GA. Previous studies of normal data allowed qualitative assessment of where abnormal cardiac dimensions lay with regard to the normal range. Z-scores from this study allow quantitative analysis of where such dimensions lie relative to the mean. This permits exact assessment of growth of fetal cardiac structures in normal hearts and particularly in congenitally abnormal hearts where quantitative assessment of the growth of cardiac structures is important in analyzing and planning treatment strategies.

Complications of supra-annular mitral valve placement in infants.

Two infants underwent supra-annular placement of prosthetic mitral valves. The objective of this strategy was to insert a larger valve and delay replacement. This approach was initially successful but by two and three years later the patients developed impairment of cardiac function. The prosthesis decreased the volume and compliance of the left atrium causing high left atrial and pulmonary venous pressures. The "ventricularised" atrium below the prosthesis dilated. In neither case was it possible to delay second valve replacement.

Diagnostic difficulties in a case of primary systemic carnitine deficiency with idiopathic dilated cardiomyopathy.

Blood spot carnitine profiles are widely used to screen for disorders of fatty acid oxidation. This case report emphasizes that a borderline concentration of free carnitine does not exclude the diagnosis of primary carnitine deficiency. Concurrent measurement of carnitine in the plasma and urine is a more sensitive test.