Project description:Recent investigations identified heterozygous CFC1 mutations in subjects with heterotaxy syndrome, all of whom had congenital cardiac malformations, including malposition of the great arteries. We hypothesized that a subset of patients with similar types of congenital heart disease---namely, transposition of the great arteries and double-outlet right ventricle, in the absence of laterality defects---would also have CFC1 mutations. Our analysis of the CFC1 gene in patients with these cardiac disorders identified two disease-related mutations in 86 patients. The present study identifies the first autosomal single-gene defect for these cardiac malformations and indicates that some cases of transposition of the great arteries and double-outlet right ventricle can share a common genetic etiology with heterotaxy syndrome. In addition, these results demonstrate that the molecular pathway involving CFC1 plays a critical role in normal and abnormal cardiovascular development.
Project description:Disease causing mutations for heterotaxy syndrome were first identified in the X-linked laterality gene, ZIC3. Mutations typically result in males with situs ambiguus and complex congenital heart disease; however affected females and one male with isolated d-transposition of the great arteries (d-TGA) have been reported. We hypothesized that a subset of patients with heart defects common to heterotaxy but without laterality defects would have ZIC3 mutations. We also sought to estimate the prevalence of ZIC3 mutations in sporadic heterotaxy. Patients with TGA (n = 169), double outlet right ventricle (DORV; n = 89), common atrioventricular canal (CAVC; n = 41), and heterotaxy (n = 54) underwent sequencing of ZIC3 exons. We tested 90 patients with tetralogy of Fallot (TOF) to correlate genotype with phenotype. Three potentially disease-related missense mutations were detected: c.49G > T (Gly17Cys) in a female with isolated DORV, c.98C > T (Ala33Val) in a male with isolated d-TGA, and c.841C > T (His281Tyr) in a female with sporadic heterotaxy. We also identified a novel insertion (CPFP333ins) in a family with heterotaxy. All were absent in 200 control patients and the 1000 Genomes Project (n = 629). No significant mutations were found in patients with TOF. Functional studies demonstrated reduced transcriptional activity of the ZIC3 His281Tyr mutant protein. ZIC3 mutations were rarely identified in isolated DORV and d-TGA suggesting that a subset of DORV and d-TGA may fall within the spectrum of laterality defects. ZIC3 mutations were found in 3.7% of patients with sporadic heterotaxy; therefore testing should be considered in patients with heterotaxy.
Project description:Surgical procedures for double-outlet right ventricle with ventricular septal defect are based on rerouting the blood flow of the left ventricle to the aorta through the ventricular septal defect (VSD) with an intraventricular baffle. The right atriotomy is the most common approach combined with a right ventriculotomy in some cases, particularly in pulmonary stenosis association. However, in complex cases, this standard operative strategy may not provide an adequate exposure. We describe the transaortic approach as an alternative procedure to repair a complex case of double-outlet right ventricle (DORV) with subaortic stenosis.Supplementary informationThe online version contains supplementary material available at 10.1007/s12055-021-01261-7.
Project description:BackgroundThe incidence of ventricular tachycardia (VT) in patients following Fontan operation is reported as 3.5%. Furthermore, in patients with repaired double outlet right ventricle (DORV), scar-related VT and outflow tract VT have been reported; however, Purkinje-related VT has not previously been reported. In this report, we present the case of idiopathic left VT (ILVT) in a patient with DORV who underwent Fontan operation.Case summaryA 31-year-old man was diagnosed as having DORV with complete atrioventricular defect at birth. When he was 17 years old, he underwent surgical repair, including extracardiac Fontan operation and common atrioventricular valve replacement. Five years later, VT was detected. Since some medications were ineffective in suppressing VT, he was referred to our hospital for definitive treatment. Ventricular tachycardia was induced by atrial and ventricular programmed electrical stimulations. The mechanism of the VT was determined to be re-entry. The earliest activation site was located at the mid-inferior septum of the hypoplastic left ventricle, in which Purkinje potentials were observed before the local ventricular electrogram. Radiofrequency catheter ablation (RFCA) was performed at this site to eliminate VT.DiscussionMost VTs originate from surgical scars in patients with congenital heart disease. Catheter ablation was feasible in scar-related VT. To the best of our knowledge, this is the first report of ILVT treated successfully with RFCA in a DORV patient who had undergone Fontan operation.
Project description:The individualized surgical approach in individuals with both arterial trunks arising from the morphologically right ventricle is dictated by the extreme morphological variability encountered in this setting, with each patient being unique. An individualized surgical approach has been designed to take account of the morphological variations, identifying the anatomy with the preoperative three-dimensional CT scan reconstruction. The key features have been considered the distance between tricuspid and pulmonary valves, the size and location of the interventricular communication, and the relationship between the outflow tracts. The surgical approach is tailored, whenever feasible, to create a connection between left ventricle and aorta, but primarily to achieve biventricular repair. Account has been taken of all available surgical options already reported in the literature, identifying the most suitable to provide the best outcomes for each unique morphology. To date, meaningful comparison between different reported surgical series has been difficult because of the marked variation of individual intracardiac morphology, and the lack of reports of specific surgical approaches for well-categorized groups of patients. Our approach, being tailored to the individual cardiac morphology, can be offered to any patient with this ventriculo-arterial connection. Given the difficulties of diagnosis, and the multiple therapeutic indications, very close collaboration between cardiologists and surgeons is indispensable for further progress in the understanding and management of this complex congenital cardiac lesion.
Project description:BackgroundDouble outlet right ventricle (DORV) describes a group of congenital heart defects where pulmonary artery and aorta originate completely or predominantly from the right ventricle. The individual anatomy of DORV patients varies widely with multiple subtypes classified. Although the majority of morphologies is suitable for biventricular repair (BVR), complex DORV anatomy can render univentricular palliation (UVP) the only option. Thus, patient-specific decision-making is critical for optimal surgical treatment planning. The evolution of image processing and rapid prototyping techniques facilitate the generation of detailed virtual and physical 3D models of the patient-specific anatomy which can support this important decision process within the Heart Team.Materilas and methodsThe individual cardiovascular anatomy of nine patients with complex DORV, in whom surgical decision-making was not straightforward, was reconstructed from either computed tomography or magnetic resonance imaging data. 3D reconstructions were used to characterize the morphologic details of DORV, such as size and location of the ventricular septal defect (VSD), atrioventricular valve size, ventricular volumes, relationship between the great arteries and their spatial relation to the VSD, outflow tract obstructions, coronary artery anatomy, etc. Additionally, physical models were generated. Virtual and physical models were used in the preoperative assessment to determine surgical treatment strategy, either BVR vs. UVP.ResultsMedian age at operation was 13.2 months (IQR: 9.6-24.0). The DORV transposition subtype was present in six patients, three patients had a DORV-ventricular septal defect subtype. Patient-specific reconstruction was feasible for all patients despite heterogeneous image quality. Complex BVR was feasible in 5/9 patients (55%). Reasons for unsuitability for BVR were AV valve chordae interfering with potential intraventricular baffle creation, ventricular hypoplasia and non-committed VSD morphology. Evaluation in particular of qualitative data from 3D models was considered to support comprehension of complex anatomy.ConclusionImage-based 3D reconstruction of patient-specific intracardiac anatomy provides valuable additional information supporting decision-making processes and surgical planning in complex cardiac malformations. Further prospective studies are required to fully appreciate the benefits of 3D technology.
Project description:ObjectiveThis population-based, comprehensive, retrospective study presented the clinical outcomes of all children born in Norway between 2003 and 2017 with double outlet right ventricle.MethodsAll children born with double outlet right ventricle between 2003 and 2017 were identified in the Oslo University Hospital registry. Patients' characteristics, interventions, complications, and deaths were recorded. Echocardiographic data were reviewed for classification according to current standards. We investigated time-dependent surgical reintervention and mortality using Kaplan-Meier analyses and determinants of treatment complications, reintervention, and death using regression analyses.ResultsNinety-three children with double outlet right ventricle represented an annual median prevalence of 1.18 per 10,000 births in Norway. Six children received palliative care. With an intention to treat, a surgical route with primary biventricular repair was followed for 62 children, staged biventricular repair for 15, and univentricular repair for 10 children. Major complications occurred in 1.0% and 6.2% children following catheter or surgical intervention, respectively. No significant determinants of the complications were identified. Overall survival following treatment was 91.9%, 90.8%, 89.5%, and 89.5% and corresponding freedom from surgical reintervention was 88.0%, 79.0%, 74.9%, and 69.4% at 1, 2, 5, and 10 years, respectively. The presence of atrioventricular septal defect predicted an increased risk of mortality (Hazard-Ratio: 7.16) but did not increase the risk of surgical reintervention.ConclusionIn Norway, most children receive tailored treatment for double outlet right ventricle with low rates of complications, surgical reinterventions, and mortality. However, atrioventricular septal defect remains a potential determinant of postoperative death.