Ethics of cardiac transplantation in hypoplastic left heart syndrome

Hypoplastic Left Heart Syndrome: A Review

Hypoplastic left heart syndrome is a rare and poorly understood congenital disorder featuring a univentricular myocardium, invariably resulting in early childhood death if left untreated. The process to palliate this congenital cardiomyopathy is of high complexity and may include invasive interventions in the first week of life. The preferred treatment strategy involves a staged correction with 3 surgical procedures at different points in time. The Norwood procedure is usually performed within the first weeks of life and aims to increase systemic circulation and relieve pulmonary vascular pressure. This procedure is followed by the bidirectional Glenn and the Fontan procedures in later life, which offer to decrease stress in the ventricular chamber. The prognosis of children with this disease has greatly improved in the past decades; however, it is still largely driven by multiple modifiable and nonmodifiable variables. Novel and clever alternatives have been proposed to improve the survival and neurodevelopment of these patients, although they are not used as standard of care in all centers. The neurodevelopmental outcomes among these patients have received particular attention in the last decade in light to improve this very limiting associated comorbidity that compromises quality of life.

Novel Insights into the Etiology, Genetics, and Embryology of Hypoplastic Left Heart Syndrome

Hypoplastic left heart syndrome (HLHS) is a relatively rare severe congenital heart defect (CHD) closely linked to other left ventricular outflow tract (LVOT) lesions including bicuspid aortic valve (BAV), one of the most common heart defects. While HLHS, BAV, and other LVOT lesions have a strong genetic underpinning, their genetic etiology remains poorly understood. Findings from a large-scale mouse mutagenesis screen showed HLHS has a multigenic etiology and is genetically heterogenous, explaining difficulties in identifying the genetic causes of HLHS. In Ohia mice, HLHS shows incomplete penetrance. Some mice exhibited small LV with normal aorta, and others a normal LV with hypoplastic aorta, indicating the LV hypoplasia is not hemodynamically driven. In Ohia mutants, HLHS was found to have a digenic modular construction, with mutation in a chromatin modifier causing the small LV phenotype and mutation in Pcdha9 causing the aorta/aortic valve hypoplasia. The Pcdha9 mutation alone can cause BAV, and in the human genome two common deletion copy number variants spanning PCDHA7-10 are associated with BAV. Hence the digenic etiology of HLHS can account for the close association of HLHS, a rare CHD, with BAV, one of the most common CHD. Functional analysis of Ohia HLHS heart tissue showed severe mitochondrial dysfunction in the small LV, while the normal size RV is also affected but milder, suggesting possible role in vulnerability of surgically palliated HLHS patients to heart failure. These findings suggest insights into the genetics of HLHS may yield new therapies for improving outcome for patients with HLHS.

Preoperative Care of Neonates With Congenital Heart Disease

Congenital heart disease (CHD) is one of the most common types of birth defects, with 40,000 newborns diagnosed yearly in the United States. This article describes: (1) four common heart defects seen in neonatal intensive care units, (2) the typical medical/nursing care of these neonates, and (3) common surgical management for the defects. Hypoplastic left heart syndrome, dextro-transposition of the great arteries, tetralogy of Fallot, and pulmonary atresia with intact ventricular septum are four common types of CHD requiring NICU admission. Knowledge of these defects will help nurses to appropriately manage and treat neonates with these types of CHD.

Adult Renal Transplantation in a Patient 28 Years after Heart Transplantation as a Neonate for Hypoplastic Left Heart Syndrome

We present a case of kidney transplantation in a 28-year-old patient who received a heart transplant at 7 weeks of age due to hypoplastic left heart syndrome. The patient's renal insufficiency was the result of chronic immunosuppression and hypertension. The almost 28-year-old graft demonstrated very good function. This patient represents as one of the longest pediatric cardiac graft recipients living without any significant functional limitations.

Hypoplastic left heart syndrome: a review

BACKGROUND

Hypoplastic left heart syndrome (HLHS) is an etiologically multifactorial congenital heart disease affecting one in 5,000 newborns. Thirty years ago there were no treatment options for this pathology and the natural course of the disease led to death, usually within the first weeks of life. Recently surgical palliative techniques have been developed allowing for a five-year survival in more than half the cases.

MATERIALS AND METHODS

We reviewed literature available on HLHS, specifically its anatomy, embryology and pathophysiology, and treatment. The Pubmed and ClinicalKey databases were searched using the key words hypoplastic left heart syndrome, foetal aortic valvuloplasty, foetal septoplasty, Norwood procedure, bidirectional Glenn procedure, Fontan procedure, hybrid procedure. The relevant literature was reviewed and included in the article. We reported a case from Children's Clinical University Hospital, Riga, to illustrate treatment tactics in Latvia.

RESULTS

There are three possible directions for therapy in newborns with HLHS: orthotopic heart transplantation, staged surgical palliation and palliative non-surgical treatment or comfort care. Another treatment mode - foetal therapy - has arisen. Staged palliation and full Fontan circulation is a temporary solution, however, the only means for survival until heart transplantation. Fifty to 70% of patients who have gone through all three stages of palliation live to the age of five years.

CONCLUSIONS

The superior mode of treatment is not yet clear and the management must be based on each individual case, the experience of each clinic, as well as the financial aspects and will of the patient's parents.

Psychosocial responses of parents to their infant's diagnosis of hypoplastic left heart syndrome

OBJECTIVE

To evaluate the psychosocial status of mothers and fathers in response to their infant's diagnosis of hypoplastic left heart syndrome.

DESIGN

A study on interviews with parents whose children had survived staged surgery.

SETTING

Tertiary hospital paediatric ICU.

SUBJECTS

A total of 29 parents (16 mothers and 13 fathers) of surviving children.

INTERVENTION

A semi-structured face-to-face interview was conducted to explore experiences of parents in response to their infant's diagnosis, their interaction with the doctor delivering the diagnosis, their deliberation about staged surgery, and their reasons for this choice.

MEASUREMENT AND MAIN RESULTS

All parents were devastated about their infant's diagnosis, and most (83%) of them said that the time of the diagnosis and the aftermath was the worst time of their lives. Parents reported helpful and unhelpful communication at this time. Although all parents in this study chose surgery for their infant, when faced with the choice, 17 of them made an immediate decision "to protect their infant's life", 8 were initially unsure when their infant was diagnosed in utero, and 4 were unsure when the infant was diagnosed after birth. Parents also experienced loss and other stressors.

CONCLUSIONS

All parents of the infants diagnosed with hypoplastic left heart syndrome experienced intense loss and stressors. Physicians need to be sensitive to the needs and thinking of the parents when discussing treatment options before surgery. The nature of the relationship with the doctor at this time can support parents or be a further source of stress.

Heart for bonding: a new protocol of care for hypoplastic left heart syndrome

There are significant challenges involved in the perinatal and postnatal care of an infant with hypoplastic left heart syndrome (HLHS) and the infant's family. In the blink of an eye, the perfect child is lost, and a fragile infant is about to join the family. This case study and discussion is an overview of HLHS , a family's desire to make the birth of their infant normal, and how that desire initiated a change in philosophy and practice in our neonatal intensive care unit.

Parental decision making regarding treatment of hypoplastic left heart syndrome

Parents of children diagnosed with a complex congenital heart anomaly such as hypoplastic left heart syndrome (HLHS) are faced with the challenge of choosing the best treatment option for their children. Parents must decide among options of compassionate care, palliative reconstructive surgery, or neonatal cardiac transplantation, and additionally with antenatal diagnosis must decide regarding continuation of pregnancy. With improved survival rates yet persistent morbidities following the Norwood surgical approach for HLHS, controversy remains whether parents should be counseled on all treatment options as evidenced by research that articulates the varied opinions of health care providers. The parents' perspective is less well researched. In this study, interview data from parents who chose the Norwood-Sano surgical option were analyzed to provide insight into the various treatment options they were given following diagnosis of HLHS in their children and how they came to choose the surgical palliation option.