Three-dimensional printing and virtual reconstruction in surgical planning of double-outlet right ventricle repair

Double outlet right ventricle - the 50% rule has always been about the conus

PURPOSE OF REVIEW

There has been much variability in the definition of double outlet right ventricle (DORV) spanning the last century. Historically, emphasis has been placed on the assignment of the great arteries to the right ventricle as a definition of DORV. In this review, we aim to underscore the importance of conal muscle, rather than rules surrounding assignment of great arteries to ventricles. We will be outlining the variability in patient anatomy that results from variations in conal muscle development in DORV, which may not fit perfectly into predefined constructs. This anatomic variability directly determines physiology and surgical repair options.

RECENT FINDINGS

There is a growing appreciation of the utility of cross-sectional imaging in complex DORV, and the generation of patient-specific 3D models with virtual reality simulations for surgical planning. These models improve the prediction of candidacy for biventricular repair and allow the mapping of complex baffle pathways preoperatively.

SUMMARY

DORV is not a disease entity in itself, but rather a vast spectrum of disorders associated with maldevelopment of conal muscle and often abnormal expansion of one the great vessels. Patient-specific 3D models will be crucial for improved surgical planning and patient outcomes.

Multicentre study on late outcomes of biventricular repair of double outlet right ventricle

OBJECTIVES

The goal of this retrospective multicentre study was to present late surgical outcomes of the treatment of children with double outlet right ventricle (DORV) coming from emerging countries.

METHODS

The Mécénat Chirurgie Cardiaque brings to France for surgery selected children with simple and complex congenital diseases, including DORV. The patients are operated on in 9 hospitals that specialize in paediatric cardiac surgery. Data are collected from the Mécénat Chirurgie Cardiaque comprehensive database, with a strict postoperative follow-up. The patients included only those who had biventricular repair of DORV with 2 viable ventricles. According to the classification of the Eleventh Revision of the International Classification of Diseases, DORV was defined as a congenital cardiovascular malformation in which both great arteries arise entirely or predominantly from the morphologically right ventricle.

RESULTS

From January 1996 to January 2022, a total of 81 consecutive DORV biventricular repair operations were performed. There were 6 subtypes of DORV divided into 2 groups: DORV-committed ventricular septal defect (VSD): DORV-VSD (n = 25), DORV-Fallot (n = 34), DORV-transposition of the great arteries (n = 5); and DORV-non-committed (nc) VSD: DORV-ncVSD-no pulmonary stenosis (PS) (n = 7), DORV-ncVSD-PS (n = 5) and DORV-atrioventricular septal defect (AVSD)-PS (n = 5). Four Fontan patients were excluded. Three patients were lost to follow-up (3.4%). The overall perioperative mortality was 7.4% ± 2.6%, 6/81 (95% confidence interval: 2.8%-15.4%) ranging from 0% in DORV-AVSD-PS to 14% for DORV-ncVSD-no PS. The overall 10-year survival was 86%. The early mortality of DORV-ncVSD at 5.9% ± 2.4% (1/17) was similar to that of DORV-committed VSD at 7.8% ± 2.7% (5/64) (P = 0.79). There was a trend towards an optimal outcome for the arterial switch operation and the DORV-AVSD-PS repair. VSD enlargement was significantly more frequent in DORV-ncVSD at 42% (5/12) (P = 0.001). There were low numbers in the complex groups. The number of Fontan cases was noticeably low. The aorta located entirely on the right ventricle represents the fundamental anomaly and the surgical challenge of DORV.

CONCLUSIONS

Overall survival at 10 years was 86%. This study shows a trend towards satisfactory early and late outcomes in BVR of simple DORV with committed VSD, compared to complex DORV with ncVSD.