Right Ventricular Outflow Tract

Background Right Ventricular Outflow Tract {RVOT} reconstruction using a conduit may be used in Tetralogy of Fallot patients who would otherwise require a trans-annular patch with the advantages of avoidance of free pulmonary regurgitation with its deleterious short and long term effects. Whereas an ideal conduit remains undefined, Contegra® bovine jugular vein bioprosthesis has been increasingly favored for this purpose worldwide. Present study summarizes the early and midterm outcome of Contegra bioprosthesis in RVOT reconstruction in patients of Tetralogy of Fallot (TOF). Methods Between Jan 2000 to April 2009, 34 patients of TOF required conduit reconstruction of RVOT using Contegra at our centre. Hospital records of these patients were retrospectively reviewed. Results Patients were in the age range of 2 to 20 years [mean age 3.2 years] and weighing between 12 to 57 kg [mean weight 15 kg].There were two early and no late deaths at a mean follow up of 23 months [range 6–110 months]. There were no reintervention or reoperations. All patients had trans-thoracic echo before leaving hospital with a mean pulmonary valve pressure gradient of 11.7 ± 6.1 mmHg. During the whole follow-up, there was no pressure gradient detectable across the conduit valve in 15 patients (44%). The maximal transvalvular peak gradients of 22–28 mmHg were measured in 3 patients (8%). Also, there was no valvular incompetence at all detectable in 20 patients (58%). Grade 1 regurgitation was seen in 10 patients (29%). Conclusions The Contegra bovine xenograft offers many advantages. It is suitable for patients of all age groups and is technically simple and safe to implant and provides excellent midterm hemodynamic results.

In the current era of superb surgical results for congenital heart disease, several management options are available for patients born with double outlet right ventricle (DORV). The surgical repair of DORV is tailored to address the variety of abnormalities associated with this lesion. The treatment strategies are dependent upon the anatomy and relationship of the ventricular septal defect (VSD) and the great arteries. For patients with subaortic or doubly committed VSDs, without right ventricular outflow tract obstruction, the usual repair is an intraventricular tunnel from the VSD to the aorta. If right ventricular outflow tract obstruction exists, then augmentation of the right ventricular outflow tract or conduit placement from the right ventricle to the pulmonary artery is necessary. For the "Taussig-Bing anomaly" (subpulmonary VSD) an arterial switch operation is indicated with tunneling of the VSD to the neoaorta. For patients with a remote VSD, complex atrioventric...

Background. The guidelines for performing a one and a half ventricle repair with pulsatile bidirectional Glenn remains controversial. This retrospective report summarizes the experience of a single institution, with an attempt at providing an answer.Methods. Fifty consecutive patients, aged 4 months to 42 years, underwent intracardiac repair along with a superior cavopulmonary connection. Twenty-seven of the patients had had previous surgical palliation. Repair consisted of patch closure of the ventricular septal defect (n = 25), tricuspid valve repair (n = 26), reconstruction of the right ventricular outflow tract (n = 34), transpulmonary annular patch (n = 34), right ventricle to pulmonary artery homograft conduit (n = 4), and concomitant repair of atrioventricular canal (n = 9). Ten patients were left with a fenestration in the atrial septum.Results. There were six hospital deaths (12%) and two late deaths (4.5%). Forty-two survivors were followed from 8 months to 116 months. Eighty-eight percent are in functional class I. Actuarial survival at 97 months was 74%.Conclusions. Moderate right heart hypoplasia constitutes a safe anatomic category for a pulsatile bidirectional Glenn. It is advisable not to proceed with a one and a half ventricle repair if postoperative residual pulmonary artery hypertension is anticipated. Patients requiring an intricate intracardiac repair and those with concomitant right heart hypoplasia may be better suited for a Fontan type of repair to reduce the complexity of the procedure.

Tetralogy of Fallot (TOF) is a relatively common congenital heart defect occurring in approximately 15% of patients with congenital heart disease. The four main anatomic features of TOF include right ventricular outflow tract (RVOT) obstruction [1, 2], ventricular septal defect (VSD), aortic dextroposition overridding the VSD, and right ventricular hypertrophy (Fig. 19.1). Current teaching postulates that the basic pathology of TOF results from underdevelopment of the right ventricular infundibulum. This underdevelopment causes an anterior malalignment of the infundibular septum which subsequently determines the degree of RVOT obstruction. The VSD that results from this malalignment is almost always large, and thus unrestrictive, permitting similar pressures between the right and left ventricles to occur. In addition to these features the pulmonary valve is frequently hypoplastic and thickened and the level of obstruction may extend to the main pulmonary artery and right and left pu...

A case of aneurysm,of the right ventricular outflow tract is described after repair of tetralogy of Fallot using a Contegra supported conduit. Angiograms,revealed that the aneurysm,was located between,the ventricular anastomosis,and the proximal ring of the conduit confirming echocardiographic data. Because the conduit between the rings was not dilated, the valve was perfectly functioning. Pulmonary anastomosis was severely stenosed explaining

This study was sought to examine the effects of repetitive monomorphic premature ventricular contractions (PVCs) on left ventricular (LV) diastolic function. Thirty-three symptomatic patients (Study group, 10 males, mean age 40 ± 8 years) with normal LV systolic function and repetitive PVCs originating from the right ventricular outflow tract (RVOT-PVCs) on 24-h Holter monitoring, and 30 healthy controls (Control group, 9 males, mean age 37 ± 9 years) were enrolled in the study. None of the patients had structural heart disease. Diastolic function was assessed by echocardiographic mitral inflow pattern and tissue Doppler imaging. The study group displayed a lower E/A ratio, longer isovolumetric relaxation time (IVRT), and longer E-wave deceleration time (EDT). In the study group 13 patients showed impaired relaxation. While mean values of the systolic velocity (Sa), early diastolic velocity (Ea), and early/late diastolic velocity (Ea/Aa) ratio were significantly lower in the study group, the Aa velocity and E/Ea ratio were significantly higher. Ea velocity was PVCs lead to abnormalities of LV diastolic function that may contribute to clinical symptoms in patients with structurally normal hearts.

Background The decision to preserve the pulmonary valve during intracardiac repair of Tetralogy of Fallot [TOF] is traditionally based on the intra-operative measurement of pulmonary annulus by a Hegar dilator as per Rowlatt’s table. We sought to evaluate if there can be flexibility in not using a transannular patch repair in Indian population with mildly hypoplastic pulmonary annulus. Methods Over a 1 year period 20 cases of TOF with a pre-operative diagnosis of mildly hypoplastic pulmonary annulus (Z  Results 5 patients had to be converted from a valve sparing repair to a trans-annular one, because of unacceptably high right ventricular pressures or hemodynamic instability on coming off cardiopulmonary bypass. The immediate post-operative mean Right Ventricular Outflow Tract (RVOT) gradients were significantly higher in group I compared to group II. Early morbidity including Intensive Care Unit (ICU) stay and incidence of right ventricular diastolic dysfunction was increased in group I. There was no difference in the immediate and mid term survival as well as the last echocardiographically estimated mean right ventricular pressures in the two groups. Conclusion Patients of TOF with a mildly hypoplastic pulmonary annulus can be safely managed by a pulmonary annulus enlarging approach. We believe in such patients a lesser risk lies in inserting a trans-annular patch. However the immediate and mid term survival is not different between annulus preserving and trans-annular approach.

Background RF ablation of frequent premature ventricular contractions (PVC) has recently been shown to improve left ventricular (LV) systolic function and dimensions in a few patients, however mainly when they originated from the right ventricular outflow tract. Methods RF ablation was performed at various ventricular locations in six consecutive patients with frequent, isolated PVC associated with idiopathic dilated cardiomyopathy (DCM). Baseline clinical status, PVC counts, LV ejection fraction (EF) and end-diastolic diameter (EDD) were recorded at baseline and at 6 months of follow-up. Results PVC ablation was performed in the right ventricle in four patients, the left ventricle in two patients. Before RF ablation, five patients were in New York Heart Association (NYHA) functional class I, and one patient was in class II. After RF ablation, the mean PVC count/24 h decreased from 17,717 ± 7,100 to 268 ± 366 (p = 0.006) while LVEF increased from 42 ± 2.5% to 57 ± 3% (p = 0.0001) and LVEDD decreased from 60.0 ± 3.5 to 54.0 ± 3.7 mm (p = 0.0009). The clinical status normalized with regression of palpitations and NYHA class. Conclusions Elimination of frequent isolated PVC in patients with DCM with RF can normalize the clinical status and LV systolic function and dimensions, regardless of the morphology or origin of the PVC.

Objective To characterise 3D deformations of the right ventricular outflow tract (RVOT)/ pulmonary arteries (PAs) during the cardiac cycle and estimate the errors of conventional 2D assessments. Methods Contrast-enhanced, ECG-gated cardiovascular computed tomography (CT) findings were retrospectively analysed from 12 patients. The acquisition of 3D images over 10 phases of the cardiac cycle created a four-dimensional CT (4DCT) dataset. The datasets were reconstructed and deformation measured at various levels of the RVOT/PAs in both space and time. Section planes were either static or dynamic relative to the motion of the structures. Results 4DCT enabled measurement and characterisation of in vivo 3D changes of patients’ RVOT/PA during the cardiac cycle. The studied patient population showed a wide range of RVOT/PA morphologies, sizes and dynamics that develop late after surgical repair of congenital heart disease. There were also significant differences in the measured cross-sectional areas of the structures between static and dynamic section planes (up to 150%, p < 0.05) secondary to large 3D displacements and rotations. Conclusions 4DCT imaging data suggest high variability in RVOT/PA dynamics and significant errors in deformation measurements if 3D analysis is not carried out. These findings play an important role for the development of novel percutaneous approaches to pulmonary valve intervention.