Right Ventricular Outflow Tract Intervention Research Articles

Decreased clinical performance in TGA-ASO patients after RVOT interventions; a multicenter European collaboration

BackgroundIn patients with transposition of the great arteries and an arterial switch operation (TGA-ASO) right ventricular outflow tract (RVOT) obstruction is a common complication requiring one or more RVOT interventions. ObjectivesWe aimed to assess cardiopulmonary exercise capacity and right ventricular function in patients stratified for type of RVOT intervention. MethodsTGA-ASO patients (≥16 years) were stratified by type of RVOT intervention. The following outcome parameters were included: predicted (%) peak oxygen uptake (peak VO2), tricuspid annular plane systolic excursion (TAPSE), tricuspid Lateral Annular Systolic Velocity (TV S′), right ventricle (RV)-arterial coupling (defined as TAPSE/RV systolic pressure ratio), and N-terminal proBNP (NT-proBNP). Results447 TGA patients with a mean age of 25.0 (interquartile range (IQR) 21–29) years were included. Patients without previous RVOT intervention (n = 338, 76%) had a significantly higher predicted peak VO2 (78.0 ± 17.4%) compared to patients with single approach catheter-based RVOT intervention (73.7 ± 12.7%), single approach surgical RVOT intervention (73.8 ± 28.1%), and patients with multiple approach RVOT intervention (66.2 ± 14.0%, p = 0.021). RV-arterial coupling was found to be significantly lower in patients with prior catheter-based and/or surgical RVOT intervention compared to patients without any RVOT intervention (p = 0.029). ConclusionsTGA patients after a successful arterial switch repair have a decreased exercise capacity. A considerable amount of TGA patients with either catheter or surgical RVOT intervention perform significantly worse compared to patients without RVOT interventions.

An In Vitro Circulatory Loop Model of the Pediatric Right Ventricular Outflow Tract as a Platform for Valve Evaluation.

Tetralogy of Fallot and other conditions affecting the right ventricular outflow tract (RVOT) are common in pediatric patients, but there is a lack of quantitative comparison among techniques for repairing or replacing the pulmonary valve. The aim of this study was to develop a robust in vitro system for quantifying flow conditions after various RVOT interventions. An infant-sized mock circulatory loop that includes a 3D-printed RVOT anatomical model was developed to evaluate flow conditions after different simulated surgical repairs. Physiologically correct flow and pressure were achieved with custom compliant tubing and a tunable flow restrictor. Pressure gradient, flow regurgitation, and coaptation height were measured for two monocusp leaflet designs after tuning the system with a 12mm Hancock valved conduit. Measurements were repeatable across multiple samples of two different monocusp designs, with the wider leaflet in the 50% backwall model consistently exhibiting lower pressure gradient but higher regurgitation compared to the leaflet in the 40% backwall model. Coaptation height was measured via direct visualization with endoscopic cameras, revealing a shorter area of contact for the wider leaflet (3.3-4.0mm) compared to the narrower one (4.3mm). The 3D-printed RVOT anatomical model and in vitro pulmonary circulatory loop developed in this work provide a platform for planning and evaluating surgical interventions in the pediatric population. Measurements of regurgitation, pressure gradient, and coaptation provide a quantitative basis for comparison among different valve designs and positions.

Palliation Strategy to Achieve Complete Repair in Symptomatic Neonates with Tetralogy of Fallot.

Neonates with symptomatic tetralogy of Fallot (sTOF) may undergo palliations with varying physiology, namely systemic to pulmonary artery connections (SPC) or right ventricular outflow tract interventions (RVOTI). A comparison of palliative strategies based on the physiology created is lacking. Consecutive sTOF neonates undergoing SPC or RVOTI from 2005-2017 were reviewed from the Congenital Cardiac Research Collaborative. The primary outcome was survival with successful complete repair (CR) by 18months. A variety of secondary outcomes were assessed including overall survival, hospitalization-related comorbidities, and interstage reinterventions. Propensity score adjustment was utilized to compare treatment strategies. The cohort included 252 SPC (surgical shunt = 226, ductus arteriosus stent = 26) and 68 RVOTI (balloon pulmonary valvuloplasty = 48, RVOT stent = 11, RVOT patch = 9) patients. Genetic syndrome (29 [42.6%] v 75 [29.8%], p = 0.04), weight < 2.5kg (28 [41.2%] v 68 [27.0%], p = 0.023), bilateral pulmonary artery Z-score < -2 (19 [28.0%] v 36 [14.3%], p = 0.008), and pre-intervention antegrade flow (48 [70.6%] v 104 [41.3%], p < 0.001) were more common in RVOTI. Significant center differences were noted (p < 0.001). Adjusted survival to CR by 18months (HR = 0.87, 95% CI = 0.63-1.21, p = 0.41) and overall survival (HR = 2.08, 95% CI = 0.93-4.65, p = 0.074) were similar. RVOTI had increased interstage reintervention (HR = 2.15, 95% CI = 1.36-3.99, p = 0.001). Total anesthesia (243 [213, 277] v 328 [308, 351] minutes, p < 0.001) and cardiopulmonary bypass times (117 [103, 132] v 151 [143, 160] minutes, p < 0.001) favored RVOTI. In this multicenter comparison of physiologic palliation strategies for sTOF, survival to successful CR and overall survival were similar; however, reintervention burden was significantly higher in RVOTI.

Outcome and right ventricle remodelling after valve replacement for pulmonic stenosis

BackgroundComplications and need for reinterventions are frequent in patients with pulmonary valve stenosis (PVS). Pulmonary regurgitation is common, but no data are available on outcome after pulmonary valve replacement (PVR).MethodsWe...

Cheatham-Platinum 10-zig stents for transcatheter treatment of congenital heart diseases: A new tool to widen the spectrum of treatable conditions

ObjectivesTo report our experience using the 10-zig C-P stents in children and adults with congenital heart disease. BackgroundThe use of stents in congenital heart disease has become widespread since the 1990s and a large range of stents has been designed for a variety of indications. In many situations there is a need for stents that can be dilated to large diameters without excessive shortening. Cheatham-Platinum (10-zig C-P) (NuMED, Hopkinton, NY, USA.) stents may fulfil this requirement. MethodsBetween January 2015 and January 2020, 17 patients with congenital heart disease were treated using a 10-zig C-P stent at our center. (6 Females 13 males; (median age 33 years (range 10–69 years); median weight 85 kgs (range 25–119 kg). Indications for use of the 10-zig stents were right ventricular outflow tract (RVOT) interventions in 8 subjects and aortic coarctation in 9 patients. Results1) Right ventricular outflow tract stenting. Ten right ventricular outflow tract stents (2 also had implantation of transcatheter valves in the same procedure) were implanted in 8 patients. All the RVOT interventions were in preparation for a transcatheter pulmonary valve. Median fluoroscopy and procedure times were 41 min (range 31–131 min) and 164 min (range 152–361 min), respectively. One patient had distal perforation of a pulmonary artery due to guide-wire injury and required blood products. Two subjects showed stent fracture during follow-up needing further stent implantation. 2) Aortic Coarctation. Nine stents were implanted in 9 patients. The median fluoroscopy and procedure times were 36 min (range 11–75 min) and 164 min (range 95–225 min), respectively. The median peak systolic gradient reduced from 33 mmHg (range 15–60 mmHg) to 3 mmHg (range 0–4 mmHg) (p < 0.001). ConclusionsOur experience shows that the 10-zig Cheatham-Platinum stents can be used successfully and safely in congenital heart diseases.

IMPACT OF PHYSIOLOGIC PALLIATION STRATEGY ON OUTCOMES IN THE SYMPTOMATIC NEONATE WITH TETRALOGY OF FALLOT: INSIGHTS FROM THE CONGENITAL CATHETERIZATION RESEARCH COLLABORATIVE

Neonates with tetralogy of Fallot and symptomatic cyanosis (sTOF) may undergo palliation to delay complete repair (CR) with a systemic to pulmonary artery connection (SPC) or right ventricular outflow tract intervention (RVOTI). Comparison of these palliative strategies is lacking. Consecutive

Current mid-term outcome with an integrated surgical strategy for correction of d-transposition of the great arteries with ventricular septal defect and left ventricular outflow tract obstruction.

The optimal surgical treatment strategy for transposition of the great arteries (TGA) associated with ventricular septal defect (VSD) and left ventricular outflow tract obstruction (LVOTO) leading to the best long-term outcome has not been established yet. The wide range of anatomical variability has led to the development of different surgical treatment options. In a retrospective single-centre review, we aimed to report the long-term outcome in patients who underwent biventricular repair. Between 1992 and 2015, 49 patients underwent biventricular repair for TGA with VSD and LVOTO. On the basis of anatomical substrate, the type of repair was chosen. According to the type of repair, the patients were divided into two groups. Group A (n = 30 patients) includes all patients who underwent intraventricular rerouting (Rastelli, n = 22; réparation à l'étage ventriculaire, n = 8); Group B patients (n = 14) had repair on an arterial level (arterial switch operation + VSD closure + LVOTO resection, n = 10; Bex-Nikaidoh, n = 4). The follow-up was completed in 90% with a median follow-up of 12.3 years (17.1-17.7 years). There was no difference in survival (Group A: 97% at 5, 10 and 15 years; Group B: 92% at 5, 10 and 15 years) and functional outcome between the groups. All patients were in New York Heart Association class I, having sinus rhythm and normal left ventricular (LV) function. Neurological and educational development was adequate for age in all but one who suffered from attention-deficit hyperactivity disorder. Group A exhibited significantly less freedom from right ventricular outflow tract (RVOT) reoperations/reintervention (79, 48 and 21% at 5, 10 and 15 years) (P = 0.008) due to RVOT dysfunction and endocarditis. Event-free LVOTO survival in Group A at 5, 10 and 15 years amounted to 96, 91 and 91% and was similar to Group B with event-free LVOTO survival at 5, 10 and 15 years of 100, 88 and 88%, respectively. LV function is well preserved irrespective of the type of procedure. Patients who had undergone intraventricular rerouting (Group A) suffered from recurrent RVOT interventions due to RVOT dysfunction and endocarditis. The neurological outcome and the educational level were adequate for age in both groups. Executing the appropriate type of surgery for the individual patient's anatomy provides excellent functional and event-free outcome.

Coronary artery compression during intention to treat right ventricle outflow with percutaneous pulmonary valve implantation: Incidence, diagnosis, and outcome

Evaluate the incidence, diagnosis, and outcome of coronary compression (CC) during right-ventricular outflow tract interventions. The incidence, risk factors, diagnosis, and outcomes of CC during percutaneous pulmonary valve implantation are poorly defined. One-hundred consecutive patients (May 2008 to January 2012) undergoing transcatheter right-ventricular outflow tract treatment in two institutions were studied. CC occurred in six patients (6%) with a right ventricular outflow conduit stenosis, at a median age of 24.5 (13-49) years. It involved the left main coronary artery in four and the right coronary artery originating from the left anterior descending coronary artery in two patients. Conduit types were homograft (n = 3), bioprosthesis (n = 2), and a pericardial patch (n = 1). Median diameter was 23 (17-24) mm at surgical implantation. CC was diagnosed through a selective coronary angiogram during balloon dilation of the conduit in the first three patients and through an aortic root angiogram for the three next cases because we recognized that proximal compression could be masked during coronary artery cannulation. It was suspected on pre-procedure imaging (magnetic resonance imaging and/or computed tomography) in three cases. Patients with abnormal coronary anatomy tend to be at increased risk of CC (P = 0.0504). One institution had a higher incidence of CC (P = 0.04). CC resolved after balloon deflation. No patient underwent conduit stenting. Four patients underwent surgical reconstruction of right ventricular outflow tract. CC is accurately diagnosed during right-ventricular outflow tract interventions. We recommend an aortic root angiogram during dilation with a non-compliant balloon matching the diameter and length of the intended conduit implant.

Outcomes and Predictors of Reintervention in Patients With Pulmonary Atresia and Intact Ventricular Septum Treated With Radiofrequency Perforation and Balloon Pulmonary Valvuloplasty

Radiofrequency perforation and valvuloplasty (RFV) is an effective initial treatment in patients with pulmonary atresia and intact ventricular septum (PA-IVS) and mild to moderate right ventricle and tricuspid valve hypoplasia. Outcomes and risk factors for the need for additional interventions in these patients are poorly defined. All patients with PA-IVS who underwent RFV at our center between January 2000 and July 2011 were reviewed. Twenty-three patients met the inclusion criteria. All patients underwent successful valvuloplasty with no procedural deaths and one major complication. Excluding two patients with limited follow-up, 6 (29%) patients underwent no subsequent interventions, whereas 9 (42%) patients underwent surgical right-ventricular outflow tract augmentation. All except one patient with adequate follow-up have a biventricular circulation with saturation >92%. Patients who did not undergo any right-ventricular outflow tract intervention after valvuloplasty had a significantly lower gradient across the pulmonary valve after valvuloplasty (9.9mmHg±8.4 vs. 19.1mmHg±10.4, p=0.05). Significantly more patients who received a supplemental source of pulmonary blood flow had a tricuspid valve z-score <-0.7 compared with patients who did not receive supplemental blood flow [2 (15%) vs. 7 (70%), p=0.008]. In our cohort of patients with PA-IVS, radiofrequency perforation with valvuloplasty was an effective and safe first step in establishing a biventricular circulation. Postvalvuloplasty pulmonary valve gradient may be predictive of subsequent outflow tract intervention, and tricuspid hypoplasia may be predictive of the need for a supplemental source of pulmonary blood flow.

286 – Percutaneous right outflow tract valve implantation: substrate matters

Percutaneous pulmonary valve insertion has been recently introduced in clinical setting. Patient selection is widely accepted. These candidates are however heterogeneous, in regard of heart defects, and type of surgical right ventricular outflow tract (RVOT) reconstruction. It is presently unclear in the literature if type of surgical reconstruction matters for the success of the pulmonary valve insertion. Our goal was to compare the hemodynamic results of percutaneous pulmonary valve in patients with homografts, prosthetic conduit or RVOT reconstructed with patch. We reviewed patients included over the last 6 months in the prospective study (REVALV) for patients undergoing RVOT intervention for severe stenosis and/or insufficiency. Only valved stent group is analyzed here. All patients undergoing valved stent implantation are previously pre-stented with a bare metal stent according to present recommendations. Thirty-seven patients were included, distributed in three groups according to type of RVOT reconstruction (homograft REVALV is a multicentric prospective study for patients undergoing RVOT intervention for severe stenosis and/or insufficiency. Patients are distributed in three groups according to type of RVOT reconstruction (homograft, n = 10; prosthetic conduit, n = 20; RVOT enlargement by patch, n = 7). Overall, all groups were similar in RV to AP gradient improvement (after pre-stenting mean 30,79 vs 28 p = NS; final result mean 23,71 vs 28,17, p = NS), RV to aorta pressures ratio (after pre-stenting 0,187 vs 0,3117 p = NS; final result man 0,315 vs 0,317, p = NS). If considering non-extensible synthetic tubes we observe that RV-to-AP improvement is significantly worst to the rest of the group (mean 7,07 vs 0,17, p = 0,005). When focusing on outflow tract diameter, results did not differ in homograft group and patch group. In contrast, diameter did play a role in those patients having a synthetic tube, with a cut-off at 20 mm diameter. Below 20 mm, relieve of outflow tract gradient was significantly worse than for bigger conduits. Pulmonary valve insertion is efficient in all type of RVOT reconstruction at least in the short term. The diameter of the conduits did not play a role in RVOT obstruction relief as long as surgical substrates are homografts or patch enlargement. In patients with prosthetic conduits, size matters. In non-extensible synthetic tubes results are worst. Reduced distensibility and progressive diameter reduction may lead to not consider these patients as good candidates for this procedure.

A new treatment option for pulmonary valvar insufficiency: first experiences with implantation of a self-expanding stented valve without use of cardiopulmonary bypass

Pulmonary regurgitation is the predominant problem in the long-term follow-up of tetralogy of Fallot (TOF) patients after primary repair. Apart from standard homograft implantation, a percutaneous valve delivery approach has been described recently. A right ventricular outflow tract (RVOT) diameter of greater than 22mm, however, precludes percutaneous valve delivery. We describe a novel technique with a transventricular implantation of a stented bio-prosthesis without cardiopulmonary bypass that allows for implantation of prosthesis with diameters greater than 22mm. All patients (9-27 years of age) had undergone total correction of TOF at a mean age of 4.2+/-4.0 years. The RVOT was enlarged at that time with a transannular patch in all but one patient. All patients presented with severe pulmonary regurgitation without any significant RVOT obstruction. Mean MRI pulmonary regurgitation was 53+/-8%. The mean magnetic resonance imaging (MRI) right ventricular end diastolic volume index (RVEDVI) was 143+/-23ml/m(2), with a mean MRI right ventricular ejection fraction (RVEF) of 46+/-9%. In another two patients indication for treatment was based on reduced exercise capacity with patients being in NYHA Class III. After repeat sternotomy, a porcine valve mounted inside a self-expandable stent, covered with No-React treated porcine pericardium (Shelhigh, Model NR-4000MIS), was introduced just beneath the RVOT without use of cardiopulmonary bypass. External sutures were placed at the proximal and distal site of the valve to ensure fixation. The implantations were uneventful, with the patients hemodynamically stable throughout the procedure. One patient with severely dilated RVOT (up to 31mm) exhibited paravalvular leakage and the valve was replaced by a homograft after 2 days. At 6-12 month follow-up the remaining five patients exhibited no more than mild pulmonary regurgitation. The mean MRI RVEDVI was 94+/-18ml/m(2), with a mean MRI RVEF of 58+/-27%. Cardiopulmonary bypass for repeat RVOT interventions can be avoided in selected patients with this newly available device. In combination with a wide range of prosthesis sizes it offers yet another important treatment option.