Ventricular Outflow Tract In Tetralogy Research Articles

Clinical Application of Individualized Pulmonary Bi-Orifice for the Reconstruction of Right Ventricular Outflow Tract in Tetralogy of Fallot.

Objective: The study aims to establish a new method in the Tetralogy of Fallot (ToF) called the pulmonary valve bi-orifice method (pulmonary annular sparing with an individualized autologous pericardial patch; thus, two orifices are formed at the level of the pulmonary valve annulus) to reconstruct the right ventricular outflow tract (RVOT).Methods: A retrospective analysis of 128 TOF patients from October 2009 to June 2018 with severe pulmonary valve dysplasia who underwent transvalvular annular patch (TAP) procedure (control group) or an individualized pulmonary valve bi-orifice procedure (observation group) were studied. The RVOT for each patient in the observation group was individually reconstructed per the patient's weight and the size of the autologous pulmonary valve using the bi-orifice method; however, increasing the cross-sectional area of the pulmonary valve annulus without destroying its integrity. The result was then compared to the control group, where TAP procedures were applied to evaluate the short to mid-term outcome(s). An in vitro simulation test was used to verify the anti-regurgitation mechanism of the new method.Results: The in vitro simulation test indicated that the anti-regurgitation mechanism was completed by the pericardial patch and the autologous pulmonary valve movement toward each other. Thus, for clinical applications, patients in both groups were compared. The results showed no significant differences in cardiopulmonary bypass and aortic cross-clamp time, mechanical ventilation, and ICU and post-operative residence between the two groups.During the follow-up period (3- to 12-years), 14 patients in the observation group had mild regurgitation after surgery (22.2%), while 10 patients had moderate pulmonary regurgitation (15.8%) with no right ventricular (RV) dilation. On the other hand, 22 patients (39.6%) had moderate to severe regurgitation in the control group, while left pulmonary artery stenosis occurred in one patient. In the control group, six patients (9.2%) with severe RV dilation were reoperated.Conclusion: Individualized pulmonary valve bi-orifice procedure is a safe and excellent method for reconstructing RVOT in ToF.

Use of angled hegar dialator for antegrade sizing of the right ventricular outflow tract in tetralogy of Fallot.

During transatrial-transpulmonary repair of tetralogy of Fallot, one of the challenges is accurately sizing the right ventricular (RV) outflow tract diameter, including the pulmonary annulus in an antegrade manner through the right atrium. This is due to the almost 90° angle between the long axis of the RV inflow through the tricuspid valve and the RV outflow through the pulmonary valve. The angled Hegar dialator, helps to accurately size the right ventricular outflow tract from the right atrium through the tricuspid valve in an antegrade manner.

Short-term outcome of Polytetrafluoroethylene Membrane Valve versus Transannular Pericardial patch Reconstruction of Right Ventricular Outflow Tract in Tetralogy of Fallot: a Randomized Controlled Trial.

IntroductionReconstruction of right ventricular outflow tract during primary repair of tetralogy of Fallot often requires the placement of a transannular patch which results in pulmonary regurgitation (PR). We compared the short-term outcomes of bicuspid polytetrafluoroethylene membrane valve versus transannular pericardial patch reconstruction of the right ventricular outflow tract.MethodsThirty consecutive patients undergoing primary repair of tetralogy of Fallot were randomly allocated to two groups - polytetrafluoroethylene valve (PTFEV) group (n=15) and transannular pericardial patch (TAP) group (n=15). The two groups had similar preoperative demographic characteristics. We compared the short-term clinical and echocardiographic outcomes between these groups. The transthoracic echocardiographic follow-up was performed at one week, one month and six months after surgery.ResultsThe PTFEV group had significantly lower central venous pressure in the immediate postoperative period compared to the TAP group (7.60±2.06 vs. 10.13±1.73, P=0.002). Extubation time was significantly shorter in the PTFEV group compared to the TAP group (12.93±7.55 hrs vs. 22.23±15.11 hrs, P=0.04). PR in the PTFEV group was absent in five patients at 24 hours post-surgery. At the study endpoint, PR was absent in six, trivial in one and mild in eight patients in the PTFEV group compared to TAP group, where all 15 patients had severe PR.ConclusionThe bicuspid polytetrafluoroethylene membrane valves significantly decrease the central venous pressure in the immediate postoperative period, facilitate early extubation and, thus, prevent ventilator-related comorbidities. They achieve a high degree of pulmonary competence and do not increase the right ventricular outflow tract gradient in short-term follow-up.

Transesophageal Echocardiographic Predictor of Significant Right Ventricular Outflow Tract Obstruction After Tetralogy of Fallot Repair

The optimal method for reconstruction of the right ventricular outflow tract in tetralogy of Fallot repair is yet to be established. Transatrial repair with pulmonary valve preservation avoids the detrimental effects of ventriculotomy and transannular patch; however, because of moderately hypoplastic pulmonary valve, these techniques are associated with undesirable residual right ventricular outflow tract gradients resulting in reoperations. The study sought to define intraoperative echocardiographic predictors of significant right ventricular outflow tract obstruction after tetralogy of Fallot repair. From July 2016 to December 2017, 58 patients with tetralogy of Fallot underwent repair with direct intraoperative pressures measuring and intraoperative transesophageal echocardiography performing after tetralogy of Fallot repair completion. Multivariate analysis was performed using logistic regression analysis to identify independent predictors of right ventricular outflow tract obstruction. One year after tetralogy of Fallot repair, significant right ventricular outflow tract obstruction was present in 12 patients (20.6%): 10 patients (26.2%) after pulmonary valve-sparing procedure and 2 patients (12.5%) after transannular patch (P = 0.35). Right ventricular outflow tract z-score lower than -3.2 had the best predictive value for significant residual right ventricular outflow tract obstruction (area under the curve = 0.979, P < 0.001). Multivariate analysis found that the right ventricular outflow tract z-score reached a statistical significance as a predictor of significant right ventricular outflow tract obstruction (P < 0.0001). Right ventricular outflow tract z-score <-3.2 measured by intraoperative transesophageal echocardiography is an indicator of postoperative right ventricular outflow tract obstruction right after surgery and a predictor of obstruction development following tetralogy of Fallot repair.

Face in Profile of Right Ventricular Outflow Tract in Tetralogy of Fallot: A Morphometric Study from Right Ventriculography

Face in Profile of Right Ventricular Outflow Tract in Tetralogy of Fallot: A Morphometric Study from Right Ventriculography

Fresh Pericardial Valved Conduit for Reconstruction of Right Ventricular Outflow Tract in Tetralogy of Fallot with Pulmonary Stenosis or Pulmonary Atresia: Early Results

Objective: To study early results of handmade fresh (autologous/homologous) pericardial valved conduit in achieving right ventricle to pulmonary artery continuity.

An in vitro study of the influence of monocusp patch size on the hemodynamics for reconstructing right ventricular outflow tract in tetralogy of Fallot.

For relief of right ventricular outflow tract obstruction in the operative treatment of tetralogy of Fallot and other complex congenital heart disease, it is often necessary to perform transannular monocusp patch to prevent right ventricular pressure overload and reduce pulmonary regurgitation. But the the geometric relationship between a monocusp patch length and the size of RVOT is not well defined. Five 20 mm sized monocusp patches were tested in simulated RVOTs which sized from 18 mm to 22 mm at 1 mm interval, respectively. The hydrodynamics of the patches were assessed through a quasi-physiological artery pulsatile flow duplicator system. The transvalvular pressure difference, effective orifice area and regurgitation flow were determined. The results showed that the regurgitation fraction increased with the diameter of RVOT increased (from 6.25% at 18 mm RVOT to 26.63% at 22 mm RVOT). Implant an oversized monocusp patch in RVOT reconstruction can effectively decrease the regurgitation but increase the transvalvular pressure and may reduce the longevity of leaflet.

Fresh Pericardial Valved Conduit for Reconstruction of Right Ventricular Outflow Tract in Tetralogy of Fallot with Pulmonary Stenosis or Pulmonary Atresia—Early Results

Objective: To study early results of hand made fresh (autologous/homologous) pericardial valved conduit in achieving right ventricle to pulmonary artery continuity. Method: Between November 2014 and September 2015, 19 cases, with diagnosis of Tetralogy of Fallot with Pulmonary stenosis (PS) or Pulmonary atresia (PA) underwent intracardiac repair and Right Ventricular Outflow Tract (RVOT) reconstruction with hand made fresh [autologous (n = 2)/ homologous (n = 17)] pericardial valved conduit. Mean age of the patients at time of surgery was 6.37 years (range 3 months to 18 years), mean weight was 18.52 kilograms (range 6 kg to 40 kg) and mean size of the conduit was 20.7 mm (range 16 mm to 24 mm). Results: All patients had a smooth post-operative course, with mean ICU (Intensive Care Unit) stay of 3.6 days (range 3 days to 6 days) and mean post-operative hospital stay 8.5 days (range 7 days to 16 days). Intra-operative and Post-operative echocardiography revealed moderate Pulmonary regurgitation (PR) in one patient, mild PR in 5 patients and no or trace PR in 13 patients. No patient has developed conduit stenosis or calcification till now. Conclusion: Autologous or homologous pericardial valved conduit provides good early results and is especially suitable for developing world because of zero cost. Long term usefulness of such option remains to be confirmed in terms of dilation, calcification and freedom from intervention.

The application of pulmonary valve biorifice for reconstruction of right ventricular outflow tract in tetralogy of Fallot

BackgroundTo introduce a new technique to create a pulmonary valve biorifice for the reconstruction of the right ventricular outflow tract in tetralogy of Fallot (TOF), and to summarize the initial clinical experiment.MethodsThe new technique of reconstructing the right ventricular outflow tract with pulmonary valve biorifice was used in 53 cases of TOF (the observation group). While the conventional technique for reconstructing the right ventricular outflow tract was used in other 50 cases of TOF (the control group). The clinical Data of all cases was reviewed retrospectively.ResultsThe ages, weights, cardiopulmonary bypass time, cardiac arrest time, as well as the post operation ventilation support time were not different significantly between groups. Unlike patients in the control group, patients from the observation group had shorter duration of ICU stay. Post- operation, in the observation group, only 2 cases had a large amount of pleural effusion, 1 case had mid-level effusion and 8 cases had a small amount of pleural effusion. While in the control group, there was 1 case of a large amount of effusion, 5 cases of mid-level effusion and 17 cases of a small amount of pleural effusion. 1 week after the operation, all patients were rechecked by echocardiography and no evidence of pulmonary valve stenosis was found. In the observation group, moderate pulmonary valve regurgitation was found in 8 cases, and mild regurgitation was observed in 15 cases. In the control group, severe regurgitation was observed in 3 cases, moderate regurgitation in 17 cases, and mild regurgitation in 16 cases. 33 cases from the observation group were rechecked six months, post-operation, and moderate-mild pulmonary regurgitation was found in 3 cases. As a follow up, 18 cases from the observation group were rechecked 1 year later, and no pulmonary regurgitation was found.ConclusionThe new technique to create pulmonary valve biorifice can reduce the pulmonary valve regurgitation, reduce postoperative pleural effusion, and improve the early surgical outcome.

The Autologous Pericardial Valved Conduit for Right Ventricular Outflow Tract Reconstruction

The repair of many complex congenital heart malformations requires the use of conduits to connect the venous ventricle to the pulmonary artery. After extensive experience with the use of pericardium for reconstruction of the right ventricular outflow tract in tetralogy of Fallot, since June 1983 we have been constructing a fresh autologous valved pericardial conduit to connect the venous ventricle with the pulmonary artery. The objective was and still is to reproduce the excellent long-term results of untreated autologous pericardial patches and unvalved conduits, obtaining adequate valve competence for the first postoperative months. Following our original description of the technique and further publication of the long-term follow-up results, this article will cover the technique of conduit construction. Table 1Size of The Pericardium Required According to The Selected Conduit DiameterRectangleTrapezoidDiameter (mm)Width of Pericardium (mm) (A-A')Height of Valves (mm) (h)Lesser Base (mm)Wider Base (mm) (a-a')12.038.011.038.042.014.044.012.544.048.516.051.013.551.056.018.056.515.056.562.020.063.016.063.069.0 Open table in a new tab Between June 1983 and December 2002, 138 autologous pericardial conduits were placed in the pulmonary position. Diagnosis included D-transposition of great arteries (n = 45 patients), truncus arteriosus (n = 30), L-transposition of great arteries (n = 28), tetralogy of Fallot, pulmonary atresia with ventricular septal defect (n = 25), and double-outlet ventricle (n = 10). Implantation age ranged from 15 days to 24 years (mean 2.9 years). Median conduit diameter was 15 mm. There were 19 (13.7%) early deaths, Of the patients, 29% had trivial, 59% mild, 9% moderate, and 3% severe pulmonary regurgitation during the early postoperative period. The 119 survivors were monitored from 1 to 19 years (mean 9.8). There were 6 late deaths. Mean conduit diameter at implantation was 16 mm, increasing to 17.9 mm at last evaluation (P < 0.0001). There were 12 reoperations, with only 3 conduit replacements. Freedom from conduit related reintervention at 5, 10, and 15 years was 90%, 81%, and 77%, respectively. In conclusion, autologous pericardial valved conduits provide good early and excellent long-term results.

Antegrade palliation for diminutive pulmonary arteries in Tetralogy of Fallot1

The purpose of this study was to evaluate the outcome following palliative reconstruction of right ventricular outflow tract in Tetralogy of Fallot (TOF) with diminutive pulmonary arteries with central and peripheral stenosis. Between 1986 and 1999 in 15 children with the diagnosis of TOF palliative reconstruction of the right ventricular outflow tract without closure of the ventricular septal defect (VSD) was performed. All patients were not suitable for an AP-Shunt because of a diminutive pulmonary vascular bed. Six patients were younger than 1 year at operation. There was one hospital death (6.7%) in a child with additional aortic valve insufficiency in multi-organ failure. Although the postoperative course was prolonged (median duration on ICU: 8 days) and complicated by congestive heart failure, clinically the 14 patients discharged improved significantly. The arterial oxygen saturation increased from 67 to 93% (P<0.001), the hemoglobin decreased from 16.1 to 13.3g/l (P=0.02) and hematocrit from 0.52 to 0.40 (P=0.06). In control angiography, the McGoon Index increased in the average from 1.01 to 1.95 (P<0.001). VSD closure was performed in 12 patients (median: 2.5 years after initial operation) with one perioperative death. A homograft had to be implanted in seven patients and a mechanical prosthesis in the right ventricular outflow tract in one. One late death occurred due to ventricular arrhythmia 12 years after antegrade palliation (11 years after corrective operation). The antegrade palliation seems to be an adequate strategy for the treatment of selected children with diminutive pulmonary arteries in TOF, who were not candidates for primary correction or an AP-Shunt.

Balloon dilation of the right ventricular outflow tract in tetralogy of Fallot: a palliative procedure

Fifteen patients requiring palliation for tetralogy of Fallot were treated by balloon dilation because of hypercyanotic spells. The mean age at dilation was 1.9 +/- 0.7 years (range 0.5-3), and the mean weight 9.8 +/- 2.1 kg (range 6.0-13.5). Dilation of the outflow tract was combined with dilation of the left and/or right pulmonary arteries in 5 patients. Successful dilation was achieved in 12 patients (80%), but failed in 3 patients with hypoplastic pulmonary arteries. In one patient, the stenosis of the right pulmonary artery could not be dilated because of a very sharp angle at the site of the stenosis. Two of the 3 patients in whom the procedure failed died of severe cyanotic spells within 24 hours of the unsuccessful procedure. No major complications occurred during or after the procedure in the cases undergoing successful dilation. The arterial oxygen saturation increased significantly, from 71 +/- 5.7% to 89 +/- 3.9%, immediately after the procedure (p < 0.005). During a period of follow up of 6 +/- 3.7 months (range 1-13), the procedure was repeated on 3 occasions, and successfully accomplished in 2 of these. In conclusion, balloon dilation is a satisfactory palliative procedure for tetralogy of Fallot in those units in which total correction is not performed under 2 to 3 years of age.

Early and late results and the effects on pulmonary arteries of balloon dilatation of the right ventricular outflow tract in tetralogy of Fallot.

Balloon dilatation of the pulmonary valve remains controversial as a palliative procedure in tetralogy of Fallot. To determine the clinical outcome, growth of the pulmonary vascular tree and findings at surgery of balloon dilatation of the pulmonary valve performed as a palliation in infants with tetralogy of Fallot. Thirty-three severely cyanosed infants (mean age of 3 months for the whole population, including seven neonates) underwent this procedure from June 1990 to January 1997. After balloon dilatation, systemic oxygen saturation increased from a mean value of 76 +/- 9% to 88 +/- 7% (P < 0.001). The procedure was accomplished without complications. Four patients had recurrent hypoxic spells after dilatation leading to surgical repair within 30 days of dilatation (three modified Blalock-Taussig shunts and one complete repair). A control study was performed at a mean of 6.1 +/- 4.5 months after dilatation in 16 patients to establish growth of the pulmonary vascular tree (repeat catheterization in nine patients and surgical pulmonary annulus calibration in seven). The pulmonary annulus increased from a mean Z score of -4.1 +/- 0.9 SD to -2.5 +/- 1.1 SD (P < 0.001). Z score for the right pulmonary artery from -3.0 +/- 0.6 SD to -1.9 +/- 1.2 SD (P = 0.007) and the Z score for the left pulmonary artery from -2.7 +/- 0.7 SD to -1.6 +/- 1.3 SD (P = 0.021). At late follow-up (mean of 9 months after dilatation, range 3 to 54 months), 28 patients underwent complete repair. Trans-annular patching was required in 43% of patients. Four post-operative deaths were observed, none dilatation related. Balloon dilatation of the pulmonary valve is an effective and safe palliation in tetralogy of Fallot. It promotes growth of the pulmonary vascular tree, reducing the need for trans-annular patching and is recommended in symptomatic infants of very young age, with a small pulmonary annulus (Z value below -4 SD) and associated cardiac anomaly.

Operative findings after percutaneous pulmonary balloon dilatation of the right ventricular outflow tract in tetralogy of Fallot.

Since 1983 percutaneous balloon dilatation of the right ventricular outflow tract has been performed as an alternative to surgical palliation in selected cases of tetralogy of Fallot at the Royal Liverpool Children's Hospital. From 31 December 1984 to 31 December 1988, 27 of these patients underwent subsequent surgical correction. Age at operation ranged from 7 to 58 months (median 2.7 years). The mean interval between balloon dilatation and correction was 15.6 months (range 3-39 months). Two patients had a systemic pulmonary shunt operation performed before dilatation and a further five required one afterwards. Overall 20 (74%) patients had some anatomical alteration as the result of balloon dilatation, while in seven (26%) there was no discernible change in the right ventricular outflow tract. There was no consistent relation between the ratio of balloon size to pulmonary annulus diameter and the morphological findings. Balloon dilatation may obviate the need for systemic-pulmonary shunt at the expense of some structural damage, particularly to the posterior cusp. The present data suggest that dilatation does not bring about growth of the annulus to such an extent that transannular patch is no longer needed at intracardiac repair.

Palliative reconstruction of right ventricular outflow tract in tetralogy with hypoplastic pulmonary arteries

Twenty-five symptomatic patients with tetralogy of Fallot underwent palliative reconstruction of the right ventricular outflow tract without closure of the ventricular septal defect. Their ages ranged from 5 months to 20 years (mean age, 3.5 yean). Eight patients had had 13 prior systemic-pulmonary arterial shunts. There were six hospital deaths (24%). Three patients needed a repeat right ventricular outflow reconstruction. There was one late death. The other patients manifested clinical improvement; hematocrit decreased from 0.54 to 0.43 ( p < 0.01) and arterial oxygen saturation increased from 63.0% to 83.2% ( p < 0.01). The size of the pulmonary artery, defined as the ratio of the sum of the diameter of the right and left pulmonary arteries to the diameter of the descending aorta, increased from 0.72 to 2.06 ( p < 0.01). Sixteen patients underwent a corrective operation 2.4 yean after palliation. The results of palliative right ventricular outflow tract reconstruction suggest that it may be an optional strategy for the treatment of symptomatic patients who have tetralogy of Fallot with severely hypoplastic pulmonary arteries.

The right ventricular outflow tract in tetralogy of Fallot by preoperative cardiac angiography

The right ventricular outflow tract in tetralogy of Fallot by preoperative cardiac angiography

Some considerations on reconstruction of the right ventricular outflow tract in tetralogy of Fallot from a viewpoint of late clinical results

Some considerations on reconstruction of the right ventricular outflow tract in tetralogy of Fallot from a viewpoint of late clinical results

Angiocardiographic evaluation of the right ventricular outflow tract in tetralogy of Fallot.

Angiocardiographic evaluation of the right ventricular outflow tract in tetralogy of Fallot.

Acquired obstruction of the right ventricular outflow tract in tetralogy of Fallot after Blalock-Taussig anastomosis. Report of two cases successfully treated with total correction.

Two patients with tetralogy of Fallot with previous functioning shunt developed obstruction of the right ventricular outflow tract. Preoperative diagnosis and total corrective surgery were successfully carried out. The acquired obstructions were clearly demonstrated by the series of angiocardiograms. Pulmonary atresia may be suspected clinically by disappearance of the systolic murmur. Acquired obstruction of the right ventricular outflow tract appears to be associated with angiocardiographic evidence of increase in the degree of overriding of the aorta. Prompt correction of the defect should be considered after angiocardiographic confirmation of the acquired atresia of the right ventricular outflow tract in such patients.