Use of prostaglandin E1 in infants with d-transposition of the great arteries and intact ventricular septum

Balloon Atrial Septostomy: Does the Balloon Size Matter?

Background

Dextro-transposition of the great arteries is a congenital heart defect with eventually lethal life-threatening consequences of hypoxic low cardiac output. When a balloon atrial septostomy (BAS) is needed, it is performed shortly after birth to create an interatrial shunt and improve systemic blood oxygenation and haemodynamic conditions. In 2019 and 2020, the withdrawal of some balloon atrioseptostomy catheters from the market led to increased use of catheters with different materials, shapes, and sizes. The main objective of this study was to investigate whether the size of the Miller and Fogarty balloon (Edwards Lifesciences) in its 2 variations, the 4.0 cc and the 1.8 cc, had a different impact on the systemic oxygen saturation, on the atrial septal defect (ASD) size, or on the type and frequency of procedure-related complications.

Methods

We conducted a retrospective study on 134 consecutive patients diagnosed with dextrotransposition of the great arteries between 2002 and 2018 who underwent BAS in a tertiary paediatric hospital in Canada.

Results

BAS resulted in a significant increase in oxygen saturation of 18.91% ± 12.95% points (P < 0.0001) and a significant increase in the resulting ASD by 3.92 ± 1.58 mm (P < 0.0001). There was no significant difference in resulting oxygen saturation (P = 0.8370) or the final ASD size (P = 0.2193) based on the balloon size. Severe or life-threatening complications were rare (1%) with no subsequent patient demise.

Conclusions

This is the first study to show that the small balloon is as efficient as the large balloon catheter including in premature patients. This raises the question whether different balloon sizes are necessary.

Prostaglandin E1 for maintaining ductal patency in neonates with ductal-dependent cardiac lesions

BACKGROUND

Prostaglandin E1 (PGE1) is used to keep the ductus arteriosus patent and can be life-saving in neonates with ductal-dependent cardiac lesions. PGE1 is used to promote mixing of pulmonary and systemic blood flow or improve pulmonary or systemic circulations, prior to balloon atrial septostomy or surgery. PGE1 therapy may cause several short-term and long-term adverse effects. The efficacy and safety of PGE1 in neonates with ductal-dependent cardiac lesions has not been systematically reviewed.

OBJECTIVES

To determine the efficacy and safety of both short-term (< 120 hours) and long-term (≥120 hours) PGE1 therapy in maintaining patency of the ductus arteriosus and decreasing mortality in ductal-dependent cardiac lesions.

SEARCH METHODS

We searched the literature in October 2017, using the search strategy recommended by Cochrane Neonatal. We searched electronic databases (CENTRAL (in the Cochrane Library), MEDLINE, CINAHL, Embase); abstracts of the Pediatric Academic Societies; websites for registered trials at www.clinicaltrials.gov and www.controlled-trials.com; and in the reference list of identified articles.

SELECTION CRITERIA

Randomized or quasi-randomized trials using PGE1 at any dose or duration to maintain ductal patency in term or late preterm (≥ 34 weeks' gestation) infants with ductal-dependent cardiac lesions and which reported effectiveness and safety in the short term or long term.

DATA COLLECTION AND ANALYSIS

We followed the standard Cochrane methods for conducting a systematic review. Two review authors (SA and MP) independently assessed the titles and abstracts of studies identified by the search strategy to determine eligibility for inclusion. We obtained the full-text version if eligibility could not be done reliably by title and abstract. We resolved any differences by discussion. We designed electronic forms for trial inclusion/exclusion, data extraction, and for requesting additional published information from authors of the original reports.

MAIN RESULTS

Our search did not identify any completed or ongoing trials that met our inclusion criteria.

AUTHORS' CONCLUSIONS

There is insufficient evidence from randomized controlled trials to determine the safety and efficacy of PGE1 in neonates with ductal-dependent cardiac lesions. Evidence from observational trials have informed clinical practice on the use of PGE, which is now considered the standard of care for ductal-dependent cardiac lesions. It is unlikely that randomized controlled studies will be performed for this indication but comparative efficacy of newer formulations of PGE1, different doses of PGE1 and studies comparing PGE with PDA stents or other measures to keep the ductus open may be ethical and necessary.

Perioperative pharmacological management of pulmonary hypertensive crisis during congenital heart surgery

Pulmonary hypertensive crisis is an important cause of morbidity and mortality in patients with pulmonary arterial hypertension secondary to congenital heart disease (PAH-CHD) who require cardiac surgery. At present, prevention and management of perioperative pulmonary hypertensive crisis is aimed at optimizing cardiopulmonary interactions by targeting prostacyclin, endothelin, and nitric oxide signaling pathways within the pulmonary circulation with various pharmacological agents. This review is aimed at familiarizing the practitioner with the current pharmacological treatment for dealing with perioperative pulmonary hypertensive crisis in PAH-CHD patients. Given the life-threatening complications associated with pulmonary hypertensive crisis, proper perioperative planning can help anticipate cardiopulmonary complications and optimize surgical outcomes in this patient population.

Transposition of great arteries: new insights into the pathogenesis

Transposition of great arteries (TGA) is one of the most common and severe congenital heart diseases (CHD). It is also one of the most mysterious CHD because it has no precedent in phylogenetic and ontogenetic development, it does not represent an alternative physiological model of blood circulation and its etiology and morphogenesis are still largely unknown. However, recent epidemiologic, experimental, and genetic data suggest new insights into the pathogenesis. TGA is very rarely associated with the most frequent genetic syndromes, such as Turner, Noonan, Williams or Marfan syndromes, and in Down syndrome, it is virtually absent. The only genetic syndrome with a strong relation with TGA is Heterotaxy. In lateralization defects TGA is frequently associated with asplenia syndrome. Moreover, TGA is rather frequent in cases of isolated dextrocardia with situs solitus, showing link with defect of visceral situs. Nowadays, the most reliable method to induce TGA consists in treating pregnant mice with retinoic acid or with retinoic acid inhibitors. Following such treatment not only cases of TGA with d-ventricular loop have been registered, but also some cases of congenitally corrected transposition of great arteries (CCTGA). In another experiment, the embryos of mice treated with retinoic acid in day 6.5 presented Heterotaxy, suggesting a relationship among these morphologically different CHD. In humans, some families, beside TGA cases, present first-degree relatives with CCTGA. This data suggest that monogenic inheritance with a variable phenotypic expression could explain the familial aggregation of TGA and CCTGA. In some of these families we previously found multiple mutations in laterality genes including Nodal and ZIC3, confirming a pathogenetic relation between TGA and Heterotaxy. These overall data suggest to include TGA in the pathogenetic group of laterality defects instead of conotruncal abnormalities due to ectomesenchymal tissue migration.

Effect of prostaglandin duration on outcomes in transposition of the great arteries with intact ventricular septum

OBJECTIVE

To study the effects of duration of preoperative prostaglandin E1 (PGE) exposure on perioperative outcomes of the arterial switch operation in patients with transposition of the great arteries with an intact ventricular septum.

DESIGN

Retrospective chart review.

SETTING

Pediatric cardiac intensive care unit in a tertiary care children's hospital.

PATIENTS

All patients with transposition of the great arteries with an intact ventricular septum from 1995 to 2008.

OUTCOME MEASURES

Inotropic score was calculated for all patients in the first 5 postoperative days and maximum inotropic score was recorded. Length of postoperative mechanical ventilation, fluid balance, mechanical ventilation time, as well as intensive care unit and hospital stay were recorded for all patients.

RESULTS

Study population included 59 patients, 41 (69%) underwent balloon atrial septostomy. PGE was used in 52 patients, median exposure of 59 hours, range 0 to 272 hours. Longer preoperative PGE exposure was associated with longer preoperative mechanical ventilation (P < .001). There was no association between preoperative PGE duration and cardiopulmonary bypass time, cross-clamp time, or total hospital stay. Patients with longer preoperative PGE exposure had a lower postoperative inotrope score (10 vs. 15 P = .02).

CONCLUSION

Greater preoperative PGE exposure was associated with prolonged preoperative mechanical ventilation. Longer PGE exposure was associated with lower postoperative inotrope requirements. Aggressive efforts to avoid or shorten PGE infusion duration may not be warranted in this population.

Impact of balloon atrial septostomy in neonates with transposition of great arteries

OBJECTIVE

To examine the impact of balloon atrial septostomy (BAS) on cardio-respiratory status, need for prostaglandin E(1) (PGE(1)) and postoperative outcomes in infants with transposition of great arteries (TGA).

STUDY DESIGN

Single-center retrospective review of consecutive neonates with dTGA.

RESULT

BAS was performed in 42 (70%) infants and resulted in a significant increase in minimum (61 to 76%) and maximum (80 to 90%) oxygen (O(2)) saturations and a drop in FiO(2). BAS was 'successful,' that is, PGE(1) was discontinued in 16 (38%) infants. Three infants died; four infants developed strokes, all of whom had undergone BAS. The duration of hospitalization, ventilation and O(2) need did not differ between infants without BAS, 'successful' BAS and unsuccessful BAS. PGE(1) duration correlated with duration of hospitalization, ventilation, O(2) need and peak respiratory severity score (P<0.03).

CONCLUSION

We speculate that limiting BAS for clinical hypoxemia and aggressive weaning of PGE(1) following BAS would improve outcomes.

Early discontinuation of intravenous prostaglandin E1 after balloon atrial septostomy is associated with an increased risk of rebound hypoxemia

OBJECTIVE

A comparison of the effects of early (<2 h) and late (>or=2 h) discontinuation of prostaglandin E1 (PGE1), on systemic oxygenation following a successful balloon atrial septostomy (BAS), in neonates with confirmed diagnosis of d-transposition of the great arteries (d-TGA).

STUDY DESIGN

Neonates with a postnatal diagnosis of d-TGA who were admitted to a quaternary neonatal intensive care unit between January 1999 and December 2004 were identified from the local database. The effects of time of discontinuation of PGE1 on oxygen saturations, oxygen requirement, need for reinstitution of prostaglandin infusion and postoperative stability were analyzed.

RESULT

Sixty neonates with a diagnosis of d-TGA were identified, 45 of whom had a BAS performed. Of these, 25 cases had early (<2 h) discontinuation of PGE1 whereas in the remaining 20 discontinuation was late (>or=2 h). PGE1 infusion was recommenced in 20 neonates (20/45 (44%)) after a successful BAS due to rebound hypoxemia. Of these, there was a threefold increase in the need for reinstitution of prostaglandin in the early compared to late discontinuation group (16/25 (64%) vs 4/20 (20%), P<0.006). There was no difference in postoperative cardiorespiratory stability.

CONCLUSION

Early discontinuation of intravenous PGE1 following BAS was associated with an increased risk of rebound hypoxemia, necessitating the recommencement of PGE1. We speculate the rapid improvement in oxygenation on reinstitution of PGE1 is secondary to pulmonary vasodilation and improved pulmonary blood flow. We propose a more cautious and graded approach to discontinuation of PGE1 based on illness severity and the magnitude and duration of hypoxemia at presentation.

Prostaglandin E1: first stage palliation in neonates with congenital cardiac defects

E-type prostaglandins (PGE1) can effectively maintain the patency of the ductus arteriosus in neonates. Its use, therefore can be life saving in infants born with ductus dependent congenital heart disease. Although PGE1 is available for over two decades in western world, it has been introduced in India only since April, 1995. Various cardiac defects where PGE1 is useful include (a) lesions with ductus dependent pulmonary blood flow e.g. pulmonary atresia with or without ventricular septal defect, critical valvular pulmonic stenosis etc, (b) lesions with ductus dependent systemic blood flow e.g. critical aortic stenosis, coarctation of aorta, interruption of aortic arch etc, and (c) admixture lesions like transposition of great arteries. The drug is given as a continuous intravenous infusion. The initial dose is 0.05 to 0.4 ug/kg/min, infusion rate must be decreased to 0.01 ug/kg/min as soon as the desired effect is achieved as incidence of side effects is more at higher doses. Serious side effects include apnoea, hypotension, hyperthermia, seizures etc. We have used this drug in 43 infants ranging in age from one to forty five days. Beneficial response was seen in 41 of 43 infants and the major side effect was apnoea (seen in 5 of 32 spontaneously breathing infants). Unfortunately the high cost of the drug prohibits its wide spread and long term use. PGE1 is a life saving drug for infants born with ductus dependent congenital cardiac malformations. It helps in stabilizing these patients prior to further surgical palliation or correction.

Long-term prostaglandin E1 therapy in congenital heart defects

Seventeen neonates received an intravenous infusion of prostaglandin E1 for an average of 39 days (range 8 to 104). Seven (group 1) had transposition of the great arteries with no ventricular septal defect or a small one; eight (group 2) had ductus-dependent pulmonary flow (pulmonary atresia or stenosis in six and tricuspid atresia in two); and two (group 3) had aortic coarctation, one with no ventricular septal defect, the other with ventricular septal defect, isthmus hypoplasia and descending aortic flow supplied mainly by the ductus. An increase in the arterial partial pressure of oxygen (PO2) was seen in groups 1 and 2. Six patients from group 1 and two from group 2 developed heart failure; cortical hyperostosis of long bones was seen in three patients from group 1 and three from group 2; one from group 1 had refractory diarrhea. Other side effects seen at the beginning improved as the rate of infusion diminished. In group 3, the patient with complex coarctation had a decrease in blood pressure in the arms, an increase in pressure in the legs and restoration of renal function; in the patient with no ventricular septal defect, heart failure worsened during therapy. Histologic changes seen in three ductus were attributed to the closing process. When delaying surgery in selected ill infants with heart defects is deemed advantageous, long-term infusions of prostaglandin E1 are feasible.

Use of prostaglandin E2 in management of transposition of great arteries before balloon atrial septostomy

Fifteen infants with transposition of the great arteries and severe hypoxaemia were treated with prostaglandin E2 infusions before atrial septostomy was performed. Twelve patients had simple transposition and three had small ventricular septal defects. The infusion resulted in a highly significant increase of PaO2 from 22 +/- 3 mmHg to 37 +/- 5 mmHg within one to two hours. Only one patient did not respond to treatment. PaO2 remained constantly above 30 mmHg throughout prostaglandin infusion. After balloon atrial septostomy prostaglandin administration was stopped. Only two patients required reinfusion within 24 hours after septostomy because of a decrease of PaO2 below 25 mmHg. At angiocardiography before balloon septostomy the ductus was of aortic size in eight, and of about half the aortic diameter in six patients. In one infant the ductus was closed. One infant had to undergo early ductus ligation because of heart failure. In 10 of 11 infants who have undergone total correction the initially large ductus had closed spontaneously.

Alprostadil (Prostin VR Pediatric Sterile Solution, The Upjohn Company)

Alprostadil is a naturally occurring prostaglandin used in the treatment of infants with congenital heart defects to maintain the patency of the ductus arteriosus until palliative or corrective surgery can be performed. In infants with defects restricting pulmonary blood flow (cyanotic), alprostadil improves arterial blood oxygenation. In infants with defects restricting systemic blood flow, alprostadil improves arterial blood pH, urine output, and femoral arterial pulses. Alprostadil is administered by continuous intraarterial or intravenous infusion, usually at a starting dose of 0.1 microgram/kg/min, with maintenance doses as low as 0.002 microgram/kg/min. The most common side effects include fever, apnea, flushing, bradycardia, hypotension, and seizures; although in some cases, some of these effects may be related to the infant's underlying condition. Literature reports of clinical experience with alprostadil are reviewed.

Long-term results after atrial repair of transposition of the great arteries in early infancy

Fifty-two patients younger than age 100 days who had an intact interventricular septum or a small ventricular septal defect underwent atrial repair of d-transposition of the great arteries (d-TGA). No patient died. To assess long-term results, we evaluated all 36 patients who had been followed for at least 1.5 years (mean 2.7 years) after surgery. The physical findings, chest roentgenograms, ECGs and echocardiograms were reviewed. Catheterization was done 6-60 months (mean 15 months) after surgery in 28 patients. Growth was normal in all but three patients. Neurologic development was abnormal in six patients (delayed speech in one patient, learning disability in three patients and preoperative cerebral infarction in two patients). The ECG showed sinus rhythm in 24 patients, minor abnormalities in nine and major dysrhythmias in three. Catheterization showed a normal cardiac index in all 28 patients. No intracardiac shunt was detected in 19 of 24 patients in whom complete oximetry data were available. One patient required reoperation for persistent atrial shunt and subsequent pacemaker placement. Two patients required baffle revision for symptoms related to superior vena caval obstruction. Right ventricular end-diastolic pressure was less than 15 mm Hg in all of 18 patients evaluated. We conclude that atrial repair of d-TGA in early infancy can be performed with a low mortality rate and a low incidence of late complications.

Treatment of d-transposition of the great arteries: management of hypoxemia after balloon atrial septostomy

Between 1975 and 1979, a group of 43 patients with d-transposition of the great arteries were diagnosed and underwent Rashkind balloon atrial septostomy at the time of initial catheterization. Thirty-six (88 percent) survived to the time of intraatrial baffle repair, and 31 (72 percent) are long-term survivors, 2 of them now awaiting repair. Palliative operations were performed in nine patients before definitive surgery; four of these patients are long-term survivors. Prostaglandin E1 infusion improved oxygenation and relieved acidosis in four patients. It is concluded that most patients with d-transposition of the great arteries will survive to elective intraatrial baffle repair between 6 and 12 months without surgical palliation in spite of significant hypoxemia. Prostaglandin E1 infusion may be lifesaving and provide sufficient palliation in patients with persistent hypoxemia and acidosis after balloon atrial septostomy.