A probabilistic neural twin for treatment planning in peripheral pulmonary artery stenosis.

The substantial computational cost of high-fidelity models in numerical hemodynamics has, so far, relegated their use mainly to offline treatment planning. New breakthroughs in data-driven architectures and optimization techniques for fast surrogate modeling provide an exciting opportunity to overcome these limitations, enabling the use of such technology for time-critical decisions. We discuss an application to the repair of multiple stenosis in peripheral pulmonary artery disease through either transcatheter pulmonary artery rehabilitation or surgery, where it is of interest to achieve desired pressures and flows at specific locations in the pulmonary artery tree, while minimizing the risk for the patient. Since different degrees of success can be achieved in practice during treatment, we formulate the problem in probability, and solve it through a sample-based approach. We propose a new offline-online pipeline for probabilistic real-time treatment planning which combines offline assimilation of boundary conditions, model reduction, and training dataset generation with online estimation of marginal probabilities, possibly conditioned on the degree of augmentation observed in already repaired lesions. Moreover, we propose a new approach for the parametrization of arbitrarily shaped vascular repairs through iterative corrections of a zero-dimensional approximant. We demonstrate this pipeline for a diseased model of the pulmonary artery tree available through the Vascular Model Repository.

[Pulmonary artery stenosis after single lung transplantation: a case report and literature review].

Objective: To summarize and analyze the clinical features, treatment, and prognosis of pulmonary artery stenosis post-lung transplantation. Methods: A 62-year-old male patient was admitted to the hospital with a cough and chest tightness of over a year's duration, which had worsened in the last two months, leading to the diagnosis of idiopathic pulmonary fibrosis. The clinical data were observed and reviewed post-left allograft single lung transplantation. Literature searches were conducted using the keywords "lung transplantation" "stenosis, pulmonary artery" and "postoperative complications" in CNKI, Wanfang Medical Network, and PubMed databases up to December 2022. Results: On January 26, 2022, a left allograft single lung transplantation was performed under general anesthesia. Postoperatively, extracorporeal membrane oxygenation and mechanical ventilation were successfully weaned off at 22 hours and 2 days, respectively, with transfer from the intensive care unit 12 days after surgery. PaO2 and PaCO2 were 50 mmHg and 40 mmHg after deoxygenation. Both pulmonary CT angiography and ventilatory-perfusion imaging indicated stenosis of the left pulmonary anastomosis. Balloon dilation and pulmonary artery stenting were performed, with PaO2 and PaCO2 improving to 87 mmHg and 42 mmHg, respectively. The patient was discharged 102 days post-surgery, and was followed up for 1 year, with a good prognosis. Additionally, 36 related articles were retrieved, encompassing 69 cases with a median age of 53 years (38.5-59.0 years). Of these, 27.54% (19/69) were diagnosed with idiopathic pulmonary fibrosis, 46.38% (32/69) underwent single lung transplantation, with the primary clinical symptom being hypoxemia in 71.01% (49/69) cases. Left pulmonary artery anastomotic stenosis was observed in 43.48% (30/69), with 65.22% (45/69) being diagnosed in the late postoperative period. Interventional therapy was performed to 44.93% (31/69), with a mortality rate of 21.74% (15/69). Conclusions: The primary clinical manifestation of post-lung transplantation pulmonary artery stenosis is hypoxemia and can be diagnosed by pulmonary artery CT angiography, transesophageal echocardiography, and pulmonary angiography. Early diagnosis can significantly reduce mortality, and interventional therapy is an effective treatment for severe pulmonary artery stenosis post-lung transplantation.

The effects of percutaneous branch pulmonary artery interventions on exercise capacity, lung perfusion, and right ventricular function in biventricular CHD: a systematic review.

BACKGROUND: Branch pulmonary artery stenosis is common after surgical repair in patients with biventricular CHD and often requires reinterventions. However, (long-term) effects of percutaneous branch pulmonary artery interventions on exercise capacity, right ventricular function, and lung perfusion remain unclear. This review describes the (long-term) effects of percutaneous branch pulmonary artery interventions on exercise capacity, right ventricular function, and lung perfusion following PRISMA guidelines. METHODS: We performed a systematic search in PubMed, Embase, and Cochrane including studies about right ventricular function, exercise capacity, and lung perfusion after percutaneous branch pulmonary artery interventions. Study selection, data extraction, and quality assessment were performed by two researchers independently. RESULTS: In total, 7 eligible studies with low (n = 2) and moderate (n = 5) risk of bias with in total 330 patients reported on right ventricular function (n = 1), exercise capacity (n = 2), and lung perfusion (n = 7). Exercise capacity and lung perfusion seem to improve after a percutaneous intervention for branch pulmonary artery stenosis. No conclusions about right ventricular function or remodelling, differences between balloon and stent angioplasty or specific CHD populations could be made. CONCLUSION: Although pulmonary artery interventions are frequently performed in biventricular CHD, data on relevant outcome parameters such as exercise capacity, lung perfusion, and right ventricular function are largely lacking. An increase in exercise capacity and improvement of lung perfusion to the affected lung has been described in case of mild to more severe pulmonary artery stenosis during relatively short follow-up. However, there is need for future studies to evaluate the effect of pulmonary artery interventions in various CHD populations.

Prevalence of Branch Pulmonary Artery Reintervention Following the Arterial Switch Operation.

BACKGROUND: The arterial switch operation (ASO) is the preferred surgical procedure used to correct dextro-transposition of the great arteries. A known complication of the ASO is branch pulmonary arteries (PAs) stenosis, which may require reintervention. Our goal is to determine the frequency of reintervention after the ASO and any factors associated with reintervention. METHODS: This was a single center, retrospective study of infants who underwent the ASO from June 6, 2011 to February 21, 2021. The primary outcome was the prevalence of reintervention on the PAs following the ASO. RESULTS: Sixty-eight infants were analyzed; 9 (13%) patients had 10 reinterventions. The mean age at time of the ASO was 6.52 ± 6.63 days; weight was 3.34 ± 0.57 kg. Those with a reintervention had a longer bypass time (P = .047). Mean age at reintervention was 0.80 ± 0.72 years; mean time from the ASO to reintervention was 0.799 ± 0.717 years. Six surgical procedures, two stent placements, and four balloon angioplasties were performed on a total of 13 branch PAs. There was no increased risk for reintervention on the right versus left PA. After reintervention, there was an improvement in the minimal PA diameter and echo gradient. There were no adverse events or mortality related to the reintervention. Mean follow-up was 6.17 ± 2.94 years. CONCLUSION: The prevalence of branch PA reintervention following the ASO in our cohort was 13%. There is an association between longer cardiopulmonary bypass time and reintervention. After reintervention, there was an increase in PA diameter and a decrease in echo gradient.

Chronic inflammatory pulmonary artery lesion causing right pulmonary artery stenosis 15 years post Blalock-Taussig shunt ligation.

Discrete central endovascular pulmonary arterial lesions raise clinical concern for malignancy such as primary pulmonary artery sarcoma. We present a case of a female in her late teens who had an obstructive mid right pulmonary artery lesion found on follow-up imaging 15 years after Tetralogy of Fallot repair. The lesion was in the vicinity of a previously ligated Blalock-Taussig shunt and causing right PA stenosis with delayed perfusion to the right lung, and a flow-related distal left PA aneurysm. The lesion was excised and confirmed histologically to be inflammatory in nature. Intraoperative microbiology demonstrated growth of the Kytococcus species, and she was managed with 6 weeks of intravenous antibiotics, with a full recovery.

Stenting of branch pulmonary artery stenosis in children: initial experience and mid-term follow-up of the pul-stent.

Not all stents are suitable for children. For instance, premounted stents can be used in infants and small children but cannot dilate with age to accommodate adult-sized pulmonary arteries. Conversely, the Pul-Stent adapts to somatic growth. Thus, our hospital implemented the Pul-Stent in pediatric patients with branch pulmonary artery stenosis. This study summarizes our initial experience with Pul-Stents in this patient population, including the efficacy and safety. We implanted 37 Pul-Stents in 35 patients between August 2014 and June 2015. The patients' mean age and weight at stent implantation were 6.7 ± 3.0 years and 20.9 ± 8.7 kg, respectively. Bench testing revealed that axial shortening of the Pul-Stent was minimal with further dilation, and the radial strength did not change. The stents were successfully deployed in all cases, except two with minor malpositioning. Primarily, 8-12 mm mounting balloons were used for the initial implantation, and a long sheath (8-10 F) was used for delivery. After stent implantation, the minimal lumen diameter in the stenosed segment increased by 50% in 97% (34/35) of patients. Furthermore, the pressure gradient across the stenosed segment decreased by 50% in 77% (23/30) of biventricular patients. One stent fracture and one stent restenosis were noted during the follow-up visits (mean follow-up time: 4.6 ± 1.7 years). Eighteen patients (51%) underwent repeat catheterization; ten had successful redilation. No aneurysms or stent fractures were observed. Our initial results indicate that the Pul-Stent is safe and effective in pediatric patients and can be further dilated over time to accommodate somatic growth. Moreover, the Pul-Stent has good compliance and adequate radial strength to treat pulmonary artery stenosis effectively.

Virtual Transcatheter Interventions for Peripheral Pulmonary Artery Stenosis in Williams and Alagille Syndromes.

Background Despite favorable outcomes of surgical pulmonary artery (PA) reconstruction, isolated proximal stenting of the central PAs is common clinical practice for patients with peripheral PA stenosis in association with Williams and Alagille syndromes. Given the technical challenges of PA reconstruction and the morbidities associated with transcatheter interventions, the hemodynamic consequences of all treatment strategies must be rigorously assessed. Our study aims to model, assess, and predict hemodynamic outcomes of transcatheter interventions in these patients. Methods and Results Isolated proximal and "extensive" interventions (stenting and/or balloon angioplasty of proximal and lobar vessels) were performed in silico on 6 patient-specific PA models. Autoregulatory adaptation of the cardiac output and downstream arterial resistance was modeled in response to intervention-induced hemodynamic perturbations. Postintervention computational fluid dynamics predictions were validated in 2 stented patients and quantitatively assessed in 4 surgical patients. Our computational methods accurately predicted postinterventional PA pressures, the primary indicators of success for treatment of peripheral PA stenosis. Proximal and extensive treatment achieved median reductions of 14% and 40% in main PA systolic pressure, 27% and 56% in pulmonary vascular resistance, and 10% and 45% in right ventricular stroke work, respectively. Conclusions In patients with Williams and Alagille syndromes, extensive transcatheter intervention is required to sufficiently reduce PA pressures and right ventricular stroke work. Transcatheter therapy was shown to be ineffective for long-segment stenosis and pales hemodynamically in comparison with published outcomes of surgical reconstruction. Regardless of the chosen strategy, a virtual treatment planning platform could identify lesions most critical for optimizing right ventricular afterload.

Echocardiographic Predictors of Ductal Tissue-Related Branch Pulmonary Artery Stenosis in Pulmonary Atresia.

Branch pulmonary artery (PA) stenosis due to ductus arteriosus (DA) tissue (DA-PS) contributes to the morbidity associated with pulmonary atresia (PAtr). We sought to identify preoperative echocardiographic features predictive of DA-PS. Patients consecutively encountered with PAtr and a DA-dependent pulmonary circulation at birth who underwent intervention in our program over a 5-year period were identified and records reviewed. Preoperative echocardiograms were reviewed to identify features that predicted postoperative DA-PS. Seventy patients with PAtr met inclusion criteria and 36 (51%) had DA-PS. At preoperative echocardiography, the proximal diameter of the PA ipsilateral to the DA was smaller in those with versus without DA-PS (Z-score - 4.8 ± 1.7 vs - 1.1 ± 1.7, respectively p < 0.001). PA origins could not be imaged on the same axial plane in 21/36 (58%) with versus 2/34 (6%) without DA-PS. Patients with DA-PS had an obtuse posterior angle of the PA bifurcation compared to those without (128 ± 17° and 87 ± 21°, p < 0.001), and a posterior angle of > 100° best predicted DA-PS with a sensitivity of 97% and specificity of 76%. An abnormal PA relationship and/or an obtuse posterior bifurcation angle had a sensitivity, specificity, positive and negative predictive value for DA-PS of 78%, 94%, 90% and 86%, respectively. Finally, DA insertion was into the ipsilateral PA in 26/36 (72%) of cases with DA-PS. A smaller proximal ipsilateral PA diameter, inability to image the PAs in the same plane, a posterior PA bifurcation angle of > 100°, and insertion of the DA in the ipsilateral PA demonstrated by echo are useful in identifying patients at risk for DA-PS.

[Medium and long-term follow-up of the Pul-Stent in treating postoperative branch pulmonary artery stenosis in children with congenital heart disease].

Objective: To evaluate the effectiveness and safety of Pul-Stent as the treatment of postoperative branch pulmonary artery stenosis in children with congenital heart disease. Methods: This was a retrospective study. Thirty-three patients who underwent Pul-Stent implantation in Shanghai Children's Medical Center due to postoperative residual pulmonary artery stenosis from August 2014 to June 2015 were included. The immediate curative effect, follow-up and complications of Pul-Stent implantation were assessed. Comparisons between groups were performed with unpaired Student t test. Results: Pul-Stent implantation of 33 patients (19 males and 14 females) were performed successfully. Thirty-one patients underwent percutaneous stenting, and 2 patients underwent hybrid stenting. A total of 35 Pul-Stents were implanted (19 of model small, 15 of model medium and one of model large), 23 stents were planted in the proximal left pulmonary artery and 12 stents were in the proximal right pulmonary artery. The initial diameter of dilation balloon ranged from 6 to 16 mm, and the long sheath of percutaneous implantation ranged from 8 to 10 F in 29 patients (29/31, 94%). After stenting, the diameter of the narrowest segment of pulmonary artery increased from (4.0±1.7) mm to (9.1±2.1) mm in all patients (t=-21.60, P<0.001). The pressure gradient at the stenosis in 26 patients after biventricular correction decreased from (30.5±12.3) mmHg (1 mmHg=0.133 kPa) to (9.9±9.6) mmHg (t=12.92, P<0.001), and the right ventricular to aortic pressure ratio decreased from 0.57±0.14 to 0.44±0.12 (t=7.44, P<0.001). The pressure of the superior vena cava after stenting in 5 patients after cavopulmonary anastomosis decreased from (17.0±1.9) mmHg to (14.0±0.7) mmHg (t=2.86, P=0.046). Two patients died during reoperation for repairing other cardiac malformations. The remaining 31 patients were clinically stable during the follow-up period of (5.3±1.6) years, and one stent fracture was found on chest X-ray. Cardiac catheterization reexaminations in 16 patients showed that restenosis was found in one stent, while stent position and patency were satisfactory in the remaining stents. Nine children underwent post-dilation without stent fracture, displacement or aneurysm formation. Cardiac tomography showed no stent stenosis, fracture observed, or significant change in diameter of the stent in 8 patients. The inner diameter and pulmonary blood perfusion could not be accurately evaluated due to artifacts by cardiac magnetic resonance imaging in 4 patients. Conclusions: Pul-Stent has good compliance and adequate radial strength, and can dilate further over time to accommodate for somatic growth. It performs safely and effectively in treating post-operative branch pulmonary artery stenosis in children.

Peripheral Pulmonary Artery Stenosis Is Not a Contraindication to a Single-ventricle Pathway.

BACKGROUND: The presence of peripheral pulmonary artery stenosis (PPAS) involving lobar and/or segmental pulmonary artery (PA) branches might preclude proceeding to a single-ventricle pathway. We adopted a strict strategy for PA rehabilitation and surgical reconstruction in patients who are unable to progress to a single-ventricle pathway. METHODS: We conducted a retrospective review of 22 patients with single-ventricle physiology who underwent surgical reconstruction for PPAS from April 2008 to March 2020. Our surgical approach was single stage in 15 patients (68.2%) and 2 stage in 7 patients (31.8%) depending on the presence or absence of PA hypoplasia distal to the PPAS. RESULTS: The PPAS was type 3 (lobar) in 19 patients (86.4%) and type 4 (segmental) in 3 patients (13.6%). The mean number of PA angioplasties performed was 8 ± 5.6 per patient. There was no mortality in this series with a median of 52 months (range, 8-143) of follow-up. Twenty patients (90.9%) were able to progress in the single-ventricle pathway with 12 patients (54.5%) undergoing a Fontan operation and 8 patients (36.4%) achieving bidirectional Glenn shunt and awaiting a Fontan operation. Two patients (9.1%) were not suitable to progress to the single-ventricle pathway because of elevated PA pressure. All patients who achieved cavopulmonary connection were alive and asymptomatic with no signs of elevation of PA pressure. No patient required further reinterventions for the PA. CONCLUSIONS: PPAS is not a contraindication for single-ventricle palliation. With careful planning and aggressive early surgical reconstruction, most of these patients can successfully progress to cavopulmonary connections.

Late Outcomes After Pulmonary Arterial Reconstruction in Patients With Arterial Tortuosity Syndrome.

BACKGROUND: Surgical pulmonary artery reconstruction in patients with arterial tortuosity syndrome has excellent outcomes. In this study, we report our late outcomes after more than a decade of experience with such complex interventions. METHODS: We conducted a retrospective review of 33 arterial tortuosity syndrome patients who underwent pulmonary artery reconstruction. The mean preoperative right ventricular to left ventricular pressure ratio was 1.19 ± 0.2. Our surgical approach included either a single-stage complete repair through a median sternotomy (17 patients) or a two-stage repair through sternotomy/left thoracotomy (16 patients), depending on the degree of distal involvement in the left pulmonary artery. RESULTS: Median age was 36 months. All patients had distal segmental peripheral pulmonary artery stenosis. Thirty patients (90.1%) were symptomatic before surgery. There was one hospital death due to viral pneumonia 78 days after the surgery (in-hospital mortality 3%). The mean right ventricular to left ventricular pressure ratio decreased to 0.31 ± 0.07 early postoperatively (P < 0.001), representing a 74% reduction compared with preoperative values. Follow-up was 100% complete for all hospital survivors (32 of 33) with a mean follow-up of 70.42 ± 43.32 months (range, 2 to 143). There was no late mortality or need for reintervention (surgical or catheter based) after hospital discharge. In late postoperative catheterization, the mean right ventricular to left ventricular pressure ratio was 0.27 ± 0.05 (P = .003 compared with early postoperative value). All patients were asymptomatic on their most recent follow-up. CONCLUSIONS: A strategy of complete surgical reconstruction of all stenotic pulmonary artery segments in patients with arterial tortuosity syndrome is recommended for sustainable successful outcomes more than a decade later.

Late outcomes of surgical reconstruction of peripheral pulmonary arteries.

OBJECTIVE: The ideal management of peripheral pulmonary artery stenosis is still controversial. We adopted a primary surgical approach to this complex lesion with excellent early outcomes. In this study, we analyzed our late outcomes. METHODS: We performed a retrospective review of 91 patients with biventricular anatomy who underwent peripheral pulmonary artery reconstruction from March 2008 to July 2020. Our surgical approach included either a single-stage complete repair through median sternotomy or a 2-stage repair through sternotomy/left thoracotomy, depending on the degree of distal involvement of the left pulmonary artery branches. RESULTS: Median age was 26 months. Syndromic etiology was established in 54 patients (59.3%) versus nonsyndromic etiology in 37 patients (40.7%). Single-stage repair was achieved in 68 patients (74.7%). There were 2 (2.2%) in-hospital mortalities. The mean right ventricular to aortic systolic pressure ratio decreased from 1.07 ± 0.20 preoperatively to 0.32 ± 0.07 immediately postoperatively (P < .001), representing a 70.1% reduction. At 1-year postoperative catheterization, the mean right ventricular to aortic systolic pressure ratio was 0.28 ± 0.05 (P < .001 compared with immediately postoperative value). With a median follow-up of 68 months (IQR, 39-117.5 months), there was no late mortality after discharge. All patients were active and asymptomatic on the most recent follow-up. There were no early or late reinterventions on pulmonary arteries. CONCLUSIONS: Late outcomes of surgical reconstruction of peripheral pulmonary arteries are excellent and durable in various pathologies (syndromic and nonsyndromic) with a significant reduction in right ventricular to aortic systolic pressure ratio, low mortality, and no reintervention.

Medium and long-term follow-up of the Pul-Stent in treating postoperative branch pulmonary artery stenosis in children with congenital heart disease / 中华儿科杂志

Objective: To evaluate the effectiveness and safety of Pul-Stent as the treatment of postoperative branch pulmonary artery stenosis in children with congenital heart disease. Methods: This was a retrospective study. Thirty-three patients who underwent Pul-Stent implantation in Shanghai Children's Medical Center due to postoperative residual pulmonary artery stenosis from August 2014 to June 2015 were included. The immediate curative effect, follow-up and complications of Pul-Stent implantation were assessed. Comparisons between groups were performed with unpaired Student t test. Results: Pul-Stent implantation of 33 patients (19 males and 14 females) were performed successfully. Thirty-one patients underwent percutaneous stenting, and 2 patients underwent hybrid stenting. A total of 35 Pul-Stents were implanted (19 of model small, 15 of model medium and one of model large), 23 stents were planted in the proximal left pulmonary artery and 12 stents were in the proximal right pulmonary artery. The initial diameter of dilation balloon ranged from 6 to 16 mm, and the long sheath of percutaneous implantation ranged from 8 to 10 F in 29 patients (29/31, 94%). After stenting, the diameter of the narrowest segment of pulmonary artery increased from (4.0±1.7) mm to (9.1±2.1) mm in all patients (t=-21.60, P<0.001). The pressure gradient at the stenosis in 26 patients after biventricular correction decreased from (30.5±12.3) mmHg (1 mmHg=0.133 kPa) to (9.9±9.6) mmHg (t=12.92, P<0.001), and the right ventricular to aortic pressure ratio decreased from 0.57±0.14 to 0.44±0.12 (t=7.44, P<0.001). The pressure of the superior vena cava after stenting in 5 patients after cavopulmonary anastomosis decreased from (17.0±1.9) mmHg to (14.0±0.7) mmHg (t=2.86, P=0.046). Two patients died during reoperation for repairing other cardiac malformations. The remaining 31 patients were clinically stable during the follow-up period of (5.3±1.6) years, and one stent fracture was found on chest X-ray. Cardiac catheterization reexaminations in 16 patients showed that restenosis was found in one stent, while stent position and patency were satisfactory in the remaining stents. Nine children underwent post-dilation without stent fracture, displacement or aneurysm formation. Cardiac tomography showed no stent stenosis, fracture observed, or significant change in diameter of the stent in 8 patients. The inner diameter and pulmonary blood perfusion could not be accurately evaluated due to artifacts by cardiac magnetic resonance imaging in 4 patients. Conclusions: Pul-Stent has good compliance and adequate radial strength, and can dilate further over time to accommodate for somatic growth. It performs safely and effectively in treating post-operative branch pulmonary artery stenosis in children.

Relationship between a Tracheal and Left Pulmonary Artery Stenosis Index and the Prognosis of Pulmonary Artery Sling with Tracheal Stenosis.

Pulmonary artery sling is a rare congenital pulmonary vascular malformation, often associated with tracheal or bronchial stenosis. Surgical treatment of pulmonary artery sling with tracheal stenosis (T) has a high risk of death and a relatively poor prognosis. This study explored the relationship between the T and left pulmonary artery stenosis (P) ratio and the effects of surgery for pulmonary artery sling with tracheal stenosis. Patients undergoing surgery for pulmonary artery sling in our center from January 2010 to December 2018 were retrospectively analyzed. Routine cardiac-enhanced computed tomography (CT) was performed preoperatively, and the P and T diameters were measured on the CT image. The T/P ratio was then calculated and analyzed. Thirty cases of pulmonary artery sling combined with tracheal stenosis were operated under cardiopulmonary bypass. The mean age at operation was 13.8 ± 13.6 months (1.2-57.1 months, Q1-Q3: 5-17 months), and the mean body weight was 8.8 ± 3.5 kg (3.8-17.3 kg, Q1-Q3: 5.8-11.5 kg). Twenty-three patients survived, and seven died, with an overall survival rate of 76.7%. Twenty-four patients underwent left pulmonary artery re-implantation, six patients underwent simultaneous left pulmonary artery re-implantation and slide tracheoplasty, and patients with intracardiac malformations (ventricular septal defect (n = 6) and atrial septal defect (n = 4)) underwent concurrent repair of the intracardiac defect. All cases had different degrees of tracheal stenosis, and the most narrowed trachea occurred with compression by the left pulmonary artery sling. The T/P ratio in the tracheoplasty group was significantly higher than that in the non-tracheoplasty group. The mortality rate in the T/P ≤ 1.15 group was significantly lower than that in the T/P > 1.15 group. Pulmonary artery sling treatment has a high risk of death. Left pulmonary artery re-implantation is an effective and safe surgical method for treating pulmonary artery sling, and slide tracheoplasty is an effective surgical method to correct tracheal stenosis. Children with T > 78.4% should receive active intervention for the tracheal stenosis, and these children have a considerable postoperative survival rate. The T/P ratio can be used to compare the relative superiority of the two compressions. A T/P ratio > 1.15 can be used as a reference index for intervention in tracheal stenosis and is a risk factor for postoperative death.

Balloon Angioplasty for Pulmonary Artery Stenosis After Complete Unifocalization and Repair of Tetralogy of Fallot With Major Aortopulmonary Collaterals.

OBJECTIVES: The objective of this study was to assess procedural outcomes of balloon pulmonary artery (PA) angioplasty procedures after complete repair of tetralogy of Fallot with major aortopulmonary collateral arteries (TOF/MAPCAs). BACKGROUND: Our approach to patients with TOF/MAPCAs emphasizes early complete unifocalization and repair. Major PA reinterventions are relatively uncommon. Balloon PA angioplasty is often used, but the effectiveness of balloon PA angioplasty in this population is unknown. METHODS: The study cohort comprised patients who underwent complete unifocalization and repair of TOF/ MAPCAs at our center between 2002-2018 and underwent balloon PA angioplasty after repair. To assess immediate procedural outcomes, pre- and postintervention PA measurements were compared. RESULTS: We reviewed 134 vessels that were dilated a median of 1.1 years after repair in 60 patients (median 2 PA branches per patient). Treated vessels included 15 central, 64 lobar, and 55 segmental branches. The median PA diameter at the level of stenosis increased from 1.9 mm to 3.3 mm (P<.001), and the median diameter increase was 50%. All but 6 treated vessels were enlarged. The stenosis-distal diameter ratio increased from a median of 64% to 89% (P<.001). The median central PA to aortic systolic pressure ratio was 47% before and 39% after intervention (P<.001). CONCLUSIONS: Balloon PA angioplasty was acutely effective at treating most stenoses of reconstructed PA branches after repair of TOF/MAPCAs. Simple angioplasty can be a useful tool in treating isolated or modest stenoses after unifocalization/PA reconstruction surgery using our approach.