Miguel Lia Tedde1,2, Sjoerd A de Beer3. 1. Thoracic Surgery Department, Heart Institute (InCor), Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de São Paulo, Brazil. 2. Hospital Alemão Oswaldo Cruz, São Paulo, Brazil. 3. Pediatric Surgical Center Amsterdam (Kinderchirurgisch Centrum Amsterdam, KCCA), Amsterdam, Netherlands.
To the editor:In addition to the excellent outcome they obtained, the case reported by Rim and Park [1] shows the boldness and inventiveness of the authors: boldness for performing the fourth surgical procedure (previously, the patient had undergone the Ravitch procedure, correction with 2 metal bars, and removal of the bars) for the repair of recurrent pectus excavatum (PE), and inventiveness for proposing a 3-dimensional-printed artificial thoracic wall, which as far as we know is an unprecedented treatment, to correct this serious defect.This case also has an important aspect that, in our view, should be emphasized. The authors describe severe instability of the patient’s thoracic wall. This finding is not unusual after the Ravitch procedure, and one of us (S.A.B.) has already reported this event in the literature [2]. This instability has been attributed to incomplete regeneration of resected cartilage, which can lead to sternocostal instability or even floating sternum, and this pathophysiological explanation has been widely accepted.However, what is worth noticing in the present case is that the patient’s sternum did not develop properly. Regardless of the incomplete regeneration of the cartilage, the “half-remaining sternum” seems to have been the main reason for the chest wall instability. Complications of the Ravitch procedure have been reported in the literature, but even in literature reviews that include many cases, there is no mention of incomplete development of the sternum [3].It’s well known that cardiac surgeons are afraid of using both mammary arteries for coronary artery grafting because of concerns over sternal devascularization and a higher risk of deep sternal wound infection [4].If sternal devascularization can be a problem in adult patients, it seems fair to believe that the extensive cartilage resection required in the Ravitch procedure performed in a young child could injure the vessels that originate in the breast and form collaterals between the sternum and the posterior intercostal arteries, which supply the sternum. This probably explains the underdevelopment of the sternum.We would like to congratulate Dr. Park and his team for their superb result and would like to emphasize that extensive operative procedures for repair of PE (and pectus carinatum) in (very) early infancy can interfere with chest wall growth and result in chest wall instability and severe pulmonary dysfunction.