Cardiac Manifestations of Twin-to-Twin Transfusion Syndrome.

This review addresses the physiology of monochorionic diamniotic (MC/DA) twins and the potential for twin-twin transfusion syndrome (TTTS). It focuses on the underlying cardiovascular pathophysiology of TTTS and the cardiovascular impact of TTTS for both the recipient and the donor twin. It explains the principles for assessment and monitoring of these cardiovascular changes and how these may be used to guide pregnancy management. Finally, it describes the effect of treatment on the altered hemodynamics and how this can influence pregnancy and perinatal management, as well as longer-term follow-up.

Does the technique of interventional closure of perimembranous ventricular septal defect reduce the incidence of heart block?

OBJECTIVE: To describe the difficulties and differing techniques in the transcatheter placement of amplatz ventricular septal defect devices to close perimembranous ventricular septal defects and place these in the context of the expanding literature on ventricular septal defect catheter closure. BACKGROUND: Surgery remains the established first-line therapy for closure of haemodynamically significant perimembranous ventricular septal defects. Transcatheter techniques appeared to promise a possible alternative, obviating the need for cardiac surgery. However, significant technical and anatomical constraints coupled with ongoing reports of a high incidence of heart block have prevented these hopes from being realised to any significant extent. It is likely that there are important methodological reasons for the high complication rates observed. The potential advantages of transcatheter perimembranous ventricular septal defect closure over surgery warrant further exploration of differing transcatheter techniques. METHODS: Between August, 2004 and November, 2009, 21 patients had a perimembranous ventricular septal defect closed with transcatheter techniques. Of these, 14 were closed with a muscular amplatz ventricular septal defect device. The median age and weight at device placement were 8 years, ranging from 2 to 19 years, and 18.6 kilograms, ranging from 10 to 21 kilograms, respectively. RESULTS: There were 25 procedures performed on 23 patients using 21 amplatz ventricular septal defect devices. Median defect size on angiography was 7.8 millimetres, ranging from 4 to 14.3 millimetres, with a median device size of 8 millimetres, ranging from 4 to 18 millimetres, and a defect/device ratio of 1.1, with a range from 0.85 to 1.33. Median procedure time was 100 minutes, with a range from 38 to 235 minutes. Adverse events included device embolisation following haemolysis in one, and new aortic incompetence in another, but there were no cases of heart block. Median follow-up was 41.7 months, with a range from 2 to 71 months. CONCLUSIONS: Evaluating transcatheter closure of perimembranous ventricular septal defect using amplatz ventricular septal defect devices remains important, if a technically feasible method with low and acceptable complication rates is to be identified. Incidence of heart block may be minimised by avoiding oversized devices, using muscular devices, and accepting defeat if an appropriately selected device pulls through. Given the current transcatheter technologies, the closure of perimembranous ventricular septal defects should generally be performed in children when they weigh at least 10 kilograms.

Echocardiographically guided catheter closure of arterial ducts in small preterm infants on the neonatal intensive care unit.

OBJECTIVE: To describe closure of haemodynamically significant arterial ducts in preterm infants using an echocardiographically guided cardiac catheter technique in selected infants in the neonatal nursery and in preference to cardiac surgery. BACKGROUND: Persistently patent arterial ducts are common in preterm infants and are associated with significant morbidity and mortality. Cardiac catheter techniques continue to improve and occlusion of arterial ducts in preterm infants is becoming technically feasible. Closure of arterial ducts by cardiac catheter techniques would enable selected infants to avoid surgery and a lateral thoracotomy, as well as potentially obviating the need for transfer of sick preterm infants between units for duct closure. METHODS AND RESULTS: This brief report describes placement of coils or Amplatzer duct devices to occlude arterial ducts in small premature infants exclusively under echocardiographic guidance in the Neonatal Intensive Care Unit. CONCLUSIONS: Closing arterial ducts in the neonatal nursery by an echocardiographically guided cardiac catheter technique with minimal morbidity is becoming achievable and is a significant advance in neonatal care.

Two generations of identical twins with ELN deletion.

We report a family with three generations of an ELN deletion. The grandfather was normal except for two inguinal herniotomies. The first generation identical twins had supravalvular aortic and multiple peripheral pulmonary artery stenoses. The second generation twins died during the neonatal period of myocardial infarcts.

Functional assessment of the evolution of congenital heart disease in utero.

PURPOSE OF REVIEW: This article reviews recent developments in the assessment of changes in structure and function in the fetal heart with the focus on congenital heart disease malformations. RECENT FINDINGS: Use of the combination of the cardiovascular profile score, the biophysical profile score and additional physiological measurements with Doppler echocardiography have allowed better characterization of disease states and the changes that can occur in utero during the last two trimesters of gestation. SUMMARY: A comprehensive examination of the structure and function of the fetal heart together with the evaluation of other parameters of fetal wellbeing are necessary for comprehensive assessment of the evolution of congenital heart disease in utero. Only such an objective surveillance can elucidate the pathophysiology and natural history, guide appropriate timing of intervention, monitor the success of any in-utero therapy, and predict perinatal outcome.

Catheter closure of the arterial duct in preterm infants.

BACKGROUND: When medical treatment of a symptomatic arterial duct in a preterm infant fails, management is surgical. PATIENTS AND METHODS: 10 preterm neonates referred to a tertiary cardiac centre for treatment of a symptomatic patent arterial duct who underwent cardiac catheterisation with the intention of device closure. RESULTS: Successful catheter device closure of the arterial duct in nine preterm infants is described. CONCLUSION: In selected cases, catheter device closure may offer an alternative to thoracotomy and surgical ligation.

A study to determine the incidence of structural congenital heart disease in monochorionic twins.

OBJECTIVE: To determine the incidence of structural heart disease in at least one of a monochorionic (MC) twin pair excluding any cardiac effects of twin-twin transfusion syndrome (TTTS). METHOD: A cohort study of 165 sets of MC twins undergoing detailed fetal echocardiography in a tertiary unit over a 4-year period. RESULTS: The overall risk of at least one of a MC twin pair having a structural congenital cardiac anomaly was 9.1% (15/165); for monochorionic diamniotic (MC/DA) twins, this figure was 7.0% (11/158) but for monochorionic-monoamniotic (MC/MA) twins the risk for at least one affected twin was 57.1% (4/7). If one of a pair of MC twins was affected, the risk to the other twin for a structural cardiac anomaly was 26.7% (4/15). CONCLUSIONS: The incidence of structural heart disease in MC twins is increased, independent of TTTS. This justifies referral of these pregnancies for detailed fetal echocardiography as part of their assessment. If one twin is affected, the risk to the other twin is increased further.