Evidence of Pulmonary Vascular Reverse Remodeling After Pulmonary Artery Banding Performed in Early Infancy in Patients With Congenital Heart Defects

Abstract

for PAB from the view point of reversibility of pulmonary vascular lesions has not been fully described. The aim of this study was to evaluate pulmonary vascular reverse remodeling after PAB using serial lung biopsy specimens and to draw conclusions on the optimal timing for PAB in terms of pulmonary vascular reverse remodeling. Methods SubjectsNumerous lung biopsy and autopsy specimens have been collected from multiple centers in Japan for diagnosing pulmonary vascular disease (PVD). Out of a total of 1,293 lung biopsy and autopsy specimens collected at our institution between January 2001 and December 2015, 41 patients who had undergone lung biopsies before and after PAB were identified. Of these, 34 patients had a ventricular septal defect (VSD) or atrioventricular septal defect (AVSD) and they were selected as the cohort for the present study. The other 7 patients with complex cardiac anomalies, such as single ventricular morphology, were excluded to evaluate P ulmonary artery banding (PAB) was introduced in 1952 as a palliative surgical procedure for the treatment of congenital heart diseases with excessive pulmonary blood flow. 1 The technique has been extensively used as part of a staged approach for the surgical correction of congenital heart defects. The procedure is also used for patients who are unable to withstand primary corrective surgery for congenital heart defects because of associated lung pathology and anatomical complexity. PAB is aimed at hemodynamic restoration and reduction of excessive blood flow and pressure in the pulmonary circulation, 2 thus protecting the pulmonary vasculature from irreversible changes that may otherwise lead to severe pulmonary arteriopathy. 3 Reverse remodeling of pulmonary arteriopathy following PAB was once reported by Wagenvoort et al more than 30 years ago; 4 medial hypertrophy and intimal lesions appeared to improve with this treatment. To the best of our knowledge, that report is the only one describing the reversibility of pulmonary artery lesions; however, histomorphometric evidence of such reversibility has not yet been well established. Additionally, the optimal timing Background: Histomorphometric evidence of the effect of pulmonary artery banding (PAB) in infancy on pulmonary vascular reverse remodeling has not been fully described.

Reverse Remodeling of Pulmonary Arterioles After Pulmonary Artery Banding in Patients ≥ 2 Years Old with Severe Pulmonary Arterial Hypertension and Congenital Heart Disease

“…After PAB, the %MS, %MT, and APSC all significantly decreased, suggesting that although grade III was the critical state of the lesion, it was still reversible. These results are supported by a study by Masaki et al [10], who showed that pulmonary arterial remodeling could be reversed after PAB. They also showed that this reversal was more important for children < 6 months of age [10], as supported by previous studies [28,29].…”

“…These results are supported by a study by Masaki et al [10], who showed that pulmonary arterial remodeling could be reversed after PAB. They also showed that this reversal was more important for children < 6 months of age [10], as supported by previous studies [28,29]. Nevertheless, the present study suggests that significant vascular remodeling takes place even when PAB is performed after 2 years of age.…”

“…Reverse remodeling occurs after PAB [10], but that the magnitude of this reversal is unknown in children operated at > 2 years of age. Therefore, the present study aimed to evaluate the pathological changes of the pulmonary arterioles in patients ≥ 2 years of age that first underwent PAB, followed by bidirectional Glenn or Fontan according to their specific conditions.…”

“…Whether congenital heart disease combined with secondary severe pulmonary arterial hypertension can be cured depends on the age of the child, as well as the severity of preoperative pulmonary vascular lesions [14]. Nevertheless, it is still controversial whether the patients can safely undergo PAB and then single ventricular repair [3][4][5][6][7][8][9][10].…”

“…In recent years, our hospital successively performed surgical treatment for the pediatric patients who had missed the optimal age of operation, and we achieved good early and mid-term results. Masaki et al [10] reported that reverse remodeling occurs after PAB, but that the magnitude of this reversal was more important before 6 months of age.…”