Cecile Tissot

Outcome of Extracorporeal Membrane Oxygenation for Early Primary Graft Failure After Pediatric Heart Transplantation

OBJECTIVES We sought to analyze the indications and outcome of extracorporeal membrane oxygenation (ECMO) for early primary graft failure and determine its impact on long-term graft function and rejection risk. BACKGROUND Early post-operative graft failure requiring ECMO can complicate heart transplantation. METHODS A retrospective review of all children requiring ECMO in the early period after transplantation from 1990 to 2007 was undertaken. RESULTS Twenty-eight (9%) of 310 children who underwent transplantation for cardiomyopathy (n = 5) or congenital heart disease (n = 23) required ECMO support. The total ischemic time was significantly longer for ECMO-rescued recipients compared with our overall transplantation population (276 +/- 86 min vs. 242 +/- 70 min, p < 0.01). The indication for transplantation, for ECMO support, and the timing of cannulation had no impact on survival. Hyperacute rejection was uncommon. Fifteen children were successfully weaned off ECMO and discharged alive (54%). Mean duration of ECMO was 2.8 days for survivors (median 3 days) compared with 4.8 days for nonsurvivors (median 5 days). There was 100% 3-year survival in the ECMO survivor group, with 13 patients (46%) currently alive at a mean follow-up of 8.1 +/- 3.8 years. The graft function was preserved (shortening fraction 36 +/- 7%), despite an increased number of early rejection episodes (1.7 +/- 1.6 vs. 0.7 +/- 1.3, overall transplant population, p < 0.05) and hemodynamically comprising rejection episodes (1.3 +/- 1.9 vs. 0.7 +/- 1.3, overall transplant population, p < 0.05). CONCLUSIONS Overall survival was 54%, with all patients surviving to at least 3 years after undergoing transplantation. None of the children requiring >4 days of ECMO support survived. Despite an increased number of early and hemodynamically compromising rejections, the long-term graft function is similar to our overall transplantation population.

Aortic valve repair by cusp extension for rheumatic aortic insufficiency in children: Long-term results and impact of extension material

OBJECTIVE Aortic valve repair has encouraging midterm results in selected patients. However, neither the long-term results of cusp extension nor the durability of different pericardial fixation techniques has been reported. Our goal was to address these issues. METHODS Seventy-eight children with severe rheumatic aortic regurgitation (mean age 12 ± 3.5 years) underwent aortic valve repair using cusp extension over a 15-year period, with fresh autologous pericardium in 53 (67.9%), glutaraldehyde-fixed bovine pericardium in 9 (11.5%), and PhotoFix bovine pericardium (Sorin CarboMedics, Milano, Italy) in 16 (20.5%). Fifty-seven children (73.1%) underwent concomitant mitral valve repair, and 8 children (10.3%) underwent tricuspid valve repair. RESULTS There was 1 operative death from left ventricular failure. During a median follow-up of 10.7 years (range 1 month to 16.4 years), 1 late death occurred and 15 patients (19.7%) required reoperation at a mean of 43 ± 33.7 months (range 1 month to 9 years), 9 within the autologous pericardium group (18%), 3 within the bovine pericardium group (33%), and 3 within the PhotoFix pericardium group (19%). Freedom from reoperation was 96% ± 2.3% at 1 year, 87.5% ± 3.9% at 5 years, 80.7% ± 4.9% at 10 years, and 75.3% ± 6% at 15 years, and was significantly decreased in the bovine pericardium group (P = .039). On multivariable analysis, greater age (hazard ratio 1.25, P < .001) and acute rheumatic carditis (hazard ratio 8.15, P = .001) at operation were significant predictors of reoperation. CONCLUSIONS Aortic cusp extension provides adequate valve repair in a large proportion of children with rheumatic aortic regurgitation. Fresh autologous and PhotoFix pericardium trended toward better durability than glutaraldehyde-fixed bovine pericardium.

Review of inhaled iloprost for the control of pulmonary artery hypertension in children

In the pediatric population, pulmonary hypertension may present as an acute event in the setting of lung or cardiac pathology or as a chronic disease, mainly as idiopathic pulmonary hypertension or associated with congenital heart disease. Recently, new pharmacologic approaches have demonstrated significant efficacy in the management of adults with pulmonary arterial hypertension; these include intravenous epoprostenol, prostacyclin analogs, endothelin receptor antagonists and phosphodiesterase type 5 inhibitors. The same treatment strategies are currently used in children. There are only few reports of the use of inhaled iloprost in pediatrics, only one of which reported the use of chronic inhaled iloprost in a significant number of children. This report showed that 1) the acute pulmonary vasodilator response to inhaled iloprost is equivalent to that of inhaled nitric oxide; 2) acute inhalation of iloprost can induce bronchoconstriction 3) the addition of inhaled iloprost can reduce the need for intravenous prostanoid therapy in some patients; 4) most children tolerated the combination of inhaled iloprost and endothelin receptor antagonist or phosphodiesterase inhibitors; 5) Several patients had clinical deterioration during chronic inhaled iloprost therapy and required rescue therapy with intravenous prostanoids. In this review we will discuss the role of inhaled iloprost in acute and chronic pulmonary hypertension in children.

Medical Therapy for Pediatric Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a life-threatening disease, the prognosis of which has changed dramatically in the past decade since the introduction of new therapeutic agents and the off-label application of adult pulmonary hypertension (PH)-specific therapies to children.1–3 However, PAH still has no cure, and the aim of treatment is to prolong survival by improving quality of life, symptoms, exercise capacity, and hemodynamics. The selection of appropriate therapies for pulmonary hypertension is complex, and they must be carefully chosen according to the etiology and pulmonary vasoreactivity.3 As insight advances into mechanisms responsible for the development of PAH, we hope the introduction of novel therapeutic agents will further improve the outcome of this disease.

Hipertensión pulmonar en los cortocircuitos congénitos

La hipertension arterial pulmonar aparece con frecuencia en los pacientes con cardiopatias congenitas. La inmensa mayoria de ellos presentan cortocircuitos cardiacos congenitos. Inicialmente pueden mostrar un cortocircuito izquierda-derecha (sistemico-pulmonar). Su evolucion natural muestra que, a medida que progresa la enfermedad, el remodelado y la disfuncion vasculares dan lugar a aumentos de la resistencia vascular pulmonar y finalmente se desarrolla un sindrome de Eisenmenger, que es la forma mas avanzada. Las anomalias anatomopatologicas y estructurales que se producen en la circulacion pulmonar de estos pacientes son, en cierta medida, similares a las que se observan en otras formas de hipertension arterial pulmonar. Basandose en este conocimiento, el tratamiento del sindrome de Eisenmenger ha sufrido cambios significativos recientemente, con la introduccion de los tratamientos dirigidos a abordar las lesiones vasculares pulmonares. El cierre mas temprano de la comunicacion cardiaca continua siendo la mejor prevencion de la lesion vascular pulmonar. Sin embargo, los parametros preoperatorios que indican que una reparacion sera segura y eficaz continuan sin estar claros, aun cuando la hemodinamica siga siendo la evaluacion habitual. La hipertension pulmonar postoperatoria, tanto en el periodo inmediato tras la reparacion quirurgica como en la evolucion a largo plazo, aun es un verdadero reto para el tratamiento. La situacion concreta de los ventriculos unicos y la circulacion de Fontan plantea tambien dificultades en presencia de lesiones vasculares pulmonares. Algunos de estos problemas se comentan en este articulo de revision de la hipertension pulmonar asociada a cortocircuitos congenitos.

Pulmonary arterial hypertension in congenital heart diseases.

Pulmonary hypertension complicates the course of many children and adults with congenital heart diseases (CHDs). The increase in pulmonary pressure associated with CHD is secondary to either increased pulmonary blood flow or increased postcapillary pressures. Pulmonary arterial hypertension is in the vast majority associated with congenital cardiac shunts. Despite major advances in the understanding of the regulation of the pulmonary vascular bed and the pulmonary endothelial lesions leading to pulmonary vascular disease, despite the advances in surgical repair and the discovery of potential therapies in the pre- and postoperative period, pulmonary hypertension still carries a significant mortality and morbidity in patients with CHD. The recent introduction of targeted therapies in other forms of pulmonary arterial hypertension has led to a renewed interest in pulmonary hypertension associated with CHD and this particularly for the most advanced form, the so-called Eisenmenger syndrome (ES). This review summarizes the current knowledge on pulmonary hypertension associated with CHD, focusing on the pathophysiology and treatment of ES.

Pulmonary Hypertension in Congenital Shunts

Pulmonary arterial hypertension frequently arises in patients with congenital heart disease. The vast majority present with congenital cardiac shunts. Initially these may manifest as left-to-right (i.e. systemic-to-pulmonary) shunts. The natural history of disease progression involves vascular remodeling and dysfunction that lead to increased pulmonary vascular resistance and, finally, to the development of Eisenmengers syndrome, which is the most advanced form. The anatomical, pathological and structural abnormalities occurring in the pulmonary circulation of these patients are, to some extent, similar to those observed in other forms of pulmonary arterial hypertension. This understanding has recently led to significant changes in the management of Eisenmengers syndrome, with the introduction of treatment specifically targeting pulmonary vascular disease. Early closure of the cardiac shunt remains the best way of preventing pulmonary vascular lesions. However, it is still not clear which preoperative parameters predict safe and successful repair, though hemodynamic evaluation is still routinely used for assessment. Postoperative pulmonary hypertension, both in the immediate period after surgical repair and during long-term follow-up, remains a real therapeutic challenge. The clinical situation of a single ventricle with Fontan circulation also presents difficulties when pulmonary vascular lesions are present. This article reviews pulmonary hypertension associated with congenital shunts and discusses a number of the specific problems encountered.

Bronchoscopic Diagnosis of Asymptomatic Unilateral Pulmonary Vein Atresia in an Infant

An eight-month-old boy with findings of persistent left pulmonary basal infiltrate was diagnosed with congenital unilateral pulmonary vein atresia by bronchoscopy. Cardiac catheterization documented slow left pulmonary venous return to atretic pulmonary veins. Conservative treatment was chosen because the child was asymptomatic and corrective surgery or percutaneous intervention was not technically possible. After a 3-year follow-up, the child still has no documented pulmonary hypertension. Early diagnosis of unilateral pulmonary vein atresia is important to anticipate potential threatening complications like pulmonary hypertension and hemoptysis. Surgical treatment of this entity might be drastic and complex and should be weighed against a conservative alternative and careful follow-up.

Outcome of Acute Graft Rejection Associated with Hemodynamic Compromise in Pediatric Heart Transplant Recipients

We sought to analyze the outcome of hemodynamically significant acute graft rejection in pediatric heart transplant recipients from a single-center experience. Acute graft rejection remains a major cause of morbidity and mortality for patients who undergo orthotopic heart transplantation and has been associated with the severity of the rejection episode. A retrospective review of all children experiencing a hemodynamically significant rejection episode after orthotopic heart transplantation was performed. Fifty-three patients with 54 grafts had 70 rejection episodes requiring intravenous inotropic support. Forty-one percent of these patients required high-dose inotropic support, with the remaining 59% of patients requiring less inotropic support. Overall graft survival to hospital discharge was 41% for patients in the high-dose group compared to 94% in the low-dose group. Six-month graft survival in patients who required high-dose inotropes remained at 41% compared to 44% in the low-dose group. Hemodynamically significant acute graft rejection in pediatric heart transplant recipients is a devastating problem with poor short- and long-term outcomes. Survival to hospital discharge is dismal in patients who require high-dose inotropic support. In contrast, survival to discharge is quite good in patients who require only low-dose inotropic support; however, six-month graft survival in this group is low secondary to a high incidence of graft failure related to worsening or aggressive transplant coronary artery disease.

Pulmonary arterial hypertension and congenital heart disease: Targeted therapies and operability

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