Percutaneous coronary artery revascularization procedures in pediatric heart transplant recipients: A large single center experience

Cardiac allograft vasculopathy: A review

BACKGROUND

Heart transplantation has become the standard of care for pediatric patients with end-stage heart disease, and outcomes have consistently improved over the last few decades. CAV, however, remains a leading cause of morbidity and mortality in heart transplantation and is the leading cause of death beyond 3 years post-transplantation. We sought out to provide an in-depth overview of CAV in the pediatric heart transplant population.

METHODS

Database searches were conducted in both Medline and Embase on the topic of cardiac vasculopathy in pediatric heart transplant recipients. The search used five broad concept terms: heart transplant; pediatric; CAV; diagnosis, prognosis, and risk factors; and guidelines and reviews. References were captured if there was at least one term in each of the concepts. The search was limited to articles in the English language.

RESULTS

A total of 148 articles were identified via the literature search with further articles identified via review of references. Pediatric data regarding the etiology and development of CAV remain limited although knowledge about the immune and non-immune factors playing a role are increasing. CAV continues to be difficult to detect with many invasive and non-invasive methods available, yet their effectiveness in the detection of CAV remains suboptimal. There remains no proven medical intervention to treat or reverse established CAV disease, and CAV is associated with high rates of graft loss once detected. However, several medications are used in hopes of preventing, slowing progression, or modifying the outcomes.

CONCLUSION

This review provides a comprehensive overview of CAV, discusses its clinical presentation, risk factors, diagnostic tools used to identify CAV in the pediatric population, and highlights the current therapeutic options and the need for ongoing research.

Stent Angioplasty for Post-Operative Coronary Artery Stenosis in Infants

INTRODUCTION

While frequently performed in the adult population, percutaneous coronary artery stent angioplasty (CSA) in infants is rare. CSA in infants is challenging because of limited options in terms of appropriately sized (length and diameter) stents, concern about stenting vessels with significant growth potential and limited data regarding durability of benefit. We report a multicenter case series of infants who underwent CSA.

METHODS

A multicenter, retrospective case series of infants who underwent percutaneous CSA to treat post-operative coronary artery stenoses was performed.

RESULTS

Six infants from 3 institutions who underwent post-operative CSA were identified. The anatomic diagnoses were d-transposition of the great arteries in 3 cases, anomalous left coronary artery from the pulmonary artery in 2 and supravalvar aortic stenosis in 1. All infants were critically ill at the time of CSA. Diameters of coronary artery stents used ranged from 2.25 to 2.75 mm. There were no procedural complications. All stents were patent immediately after placement and the clinical condition improved or stabilized in all patients. Follow-up angiography was available for 3 patients at 4 to 16 months post-CSA, at which time 67% (2/3) remained patent.

CONCLUSION

CSA is a feasible and effective therapy for critically ill infants with post-surgical coronary obstruction. Treatment appears to allow at least short-term reperfusion to facilitate recovery of ventricular function and potential development of collateral circulation when longer-term stent patency is not achieved. Longer-term stent patency and coronary artery health remain unanswered questions.

Heart Retransplantation for Coronary Allograft Vasculopathy in Children: 25 Years of Single-Center Experience

BACKGROUND

Pediatric end-stage heart disease is surgically managed by heart transplantation. A major complication of primary transplantation (PTx) is coronary allograft vasculopathy (CAV), a form of accelerated atherosclerosis. Retransplantation (RTx) has been the management of CAV; however, there is limited comprehensive literature on this subject. Here we report 25 years of single-center experience in managing CAV with RTx and place it in the context of recent studies.

METHODS

A retrospective cohort study was undertaken on patients who underwent PTx <18 years old and subsequent RTx due to CAV at the Heart Institute (InCor) University of São Paulo Medical School between 1992 and 2018. The maintenance immunosuppression protocol was double immunosuppression. For both PTx and RTx, quantitative and qualitative analyses were conducted for transplantation indication, donor/recipient demographics, post-transplant survival, rejection, infection, and immunosuppression.

RESULTS

Between 1992 and 2018, 200 children underwent heart transplantation. Ten re-transplantations were performed, for which 7 (70%) were for CAV. Ages at RTx ranged from 11.5 to 29.3 years (19.1 ± 5.68 years; median 18.2 years). The mean time between PTx and RTx was 12.9 ± 3.4 years (median 13.4 years). The Kaplan-Meier survival rate at 1 month, 3 years, and 5 years was 85.7%, 71.5%, and 47.6%, respectively.

CONCLUSION

Cardiac RTx can be a management option for CAV in patients who have undergone PTx in childhood with double immunosuppression therapy.