The effects of percutaneous branch pulmonary artery interventions in biventricular congenital heart disease: study protocol for a randomized controlled Dutch multicenter interventional trial.

BACKGROUND: Branch pulmonary artery (PA) stenosis is one of the most common indications for percutaneous interventions in patients with transposition of the great arteries (TGA), tetralogy of Fallot (ToF), and truncus arteriosus (TA). However, the effects of percutaneous branch PA interventions on exercise capacity remains largely unknown. In addition, there is no consensus about the optimal timing of the intervention for asymptomatic patients according to international guidelines. This trial aims to identify the effects of percutaneous interventions for branch PA stenosis on exercise capacity in patients with TGA, ToF, and TA. In addition, it aims to assess the effects on RV function and to define early markers for RV adaptation and RV dysfunction to improve timing of these interventions. METHODS: This is a randomized multicenter interventional trial. TGA, ToF, and TA patients ≥ 8 years with a class IIa indication for percutaneous branch PA intervention according to international guidelines are eligible to participate. Patients will be randomized into the intervention group or the control group (conservative management for 6 months). All patients will undergo transthoracic echocardiography, cardiac magnetic resonance (CMR) imaging, and cardiopulmonary exercise testing at baseline, 6 months, and 2-4 years follow-up. Quality of life (QoL) questionnaires will be obtained at baseline, 2 weeks post intervention or a similar range for the control group, and 6 months follow-up. The primary outcome is exercise capacity expressed as maximum oxygen uptake (peak VO2 as percentage of predicted). A total of 56 patients (intervention group n = 28, control group n = 28) is required to demonstrate a 14% increase in maximum oxygen uptake (peak VO2 as percentage of predicted) in the interventional group compared to the control group (power 80%, overall type 1 error controlled at 5%). Secondary outcomes include various parameters for RV systolic function, RV functionality, RV remodeling, procedural success, complications, lung perfusion, and QoL. DISCUSSION: This trial will investigate the effects of percutaneous branch PA interventions on exercise capacity in patients with TGA, ToF, and TA and will identify early markers for RV adaptation and RV dysfunction to improve timing of the interventions. TRIAL REGISTRATION: ClinicalTrials.gov NCT05809310. Registered on March 15, 2023.

Total pulmonary arterial reconstruction in a patient with arterial tortuosity syndrome affecting the pulmonary artery: a case report and review of the literature.

BACKGROUND: Arterial tortuosity syndrome is a rare Autosomal recessive disease that leads to a loss of function of the connective tissues of the body, this happens due to a mutation in the solute carrier family 2 member 10 (SLC2A10) gene. ATS is more likely to occur in Large and medium-sized arteries including the aorta and pulmonary arteries. This syndrome causes the arteries to be elongated and tortuous, This tortuosity disturbs the blood circulation resulting in stenosis and lack of blood flow to organs and this chronic turbulent flow increases the risk of aneurysm development, dissection and ischemic events. CASE PRESENTATION: A 2 years old Arabian female child was diagnosed with ATS affecting the pulmonary arteries as a newborn, underwent a pulmonary arterial surgical reconstruction at the age of 2 years old due to the development of pulmonary artery stenosis with left pulmonary artery having a peak gradient of 73 mmHg with a peak velocity of 4.3 m/s and the right pulmonary artery having a peak gradient of 46 mmHg with a peak velocity of 3.4 m/s causing right ventricular hypertension. After surgical repair the left pulmonary artery has a peak pressure gradient of 20 mmHg, with the right pulmonary artery having a peak pressure gradient of 20 mmHg. CONCLUSION: ATS is a rare genetic condition that affects the great arteries especially the pulmonary arteries causing stenotic and tortuous vessels that may be central branches or distal peripheral branches that leads to severe right ventricular dysfunction and hypertension. We believe that surgical treatment provides the optimum outcomes when compared to transcather approaches especially when the peripheral arteries are involved. Some challenges and hiccups might occur, especially lung reperfusion injury that needs to be diagnosed and treated accordingly.

Sarcoidosis-associated pulmonary hypertension due to pulmonary arteries stenosis - a case report.

BACKGROUND: Sarcoidosis-associated pulmonary hypertension (SAPH) is listed in Group 5 of the clinical classification of pulmonary hypertension, due to its complex and multifactorial pathophysiology. The most common cause of SAPH development is advanced lung fibrosis with the associated destruction of the vascular bed, and/or alveolar hypoxia. However, a substantial proportion of SAPH patients (up to 30%) do not have significant fibrosis on chest imaging. In such cases, the development of pulmonary hypertension may be due to the lesions directly affecting the pulmonary vasculature, such as granulomatous angiitis, pulmonary veno-occlusive disease, chronic thromboembolism or external compression of vessels by enlarged lymph nodes. Based on the case of a 69-year-old female who developed SAPH due to pulmonary arteries stenosis, diagnostic difficulties and therapeutic management are discussed. CASE PRESENTATION: The patient, non-smoking female, diagnosed with stage II sarcoidosis twelve years earlier, presented with progressive dyspnoea on exertion, dry cough, minor haemoptysis and increasing oedema of the lower limbs. Computed tomography pulmonary angiography (CTPA) showed complete occlusion of the right upper lobe artery and narrowing of the left lower lobe artery, with post-stenotic dilatation of the arteries of the basal segments. The vascular pathology was caused by adjacent, enlarged lymph nodes with calcifications and fibrotic tissue surrounding the vessels. Pulmonary artery thrombi were not found. The patient was treated with systemic corticosteroid therapy and subsequently with balloon pulmonary angioplasty. Partial improvement in clinical status and hemodynamic parameters has been achieved. CONCLUSIONS: An appropriate screening strategy is required for early detection of pulmonary hypertension in sarcoidosis patients. Once SAPH diagnosis is confirmed, it is crucial to determine the appropriate phenotype of pulmonary hypertension and provide the most effective treatment plan. Although determining SAPH phenotype is challenging, one should remember about the possibility of pulmonary arteries occlusion.

Prevalence and Clinical Characteristics of Heterozygous RNF213 p.Arg4810Lys Variant Carriers Diagnosed With Chronic Thromboembolic Pulmonary Hypertension.

BACKGROUND: Ring finger protein 213 (RNF213) p.Arg4810Lys is a susceptibility gene for moyamoya disease, peripheral pulmonary artery stenosis (PPS), and other vascular diseases and thrombosis. We investigated the prevalence and clinical characteristics of RNF213 variant carriers diagnosed with chronic thromboembolic pulmonary hypertension (CTEPH). METHODS AND RESULTS: We retrospectively analyzed the prevalence of the RNF213 p.Arg4810Lys variant in patients diagnosed with CTEPH (n=112) and PPS (n=10). Clinical and angiographic characteristics were evaluated between RNF213 variant carriers diagnosed with CTEPH and noncarriers with CTEPH and homozygous variant carriers with PPS. Eight heterozygous RNF213 p.Arg4810Lys variant carriers (7.1%) were identified among patients diagnosed with CTEPH, while 5 patients with PPS (50%) carried the homozygous variant. The clinical characteristics of heterozygous variant carriers with CTEPH were not remarkably different from those of noncarriers with CTEPH. All heterozygous variant carriers with CTEPH showed webs/bands lesions at the segmental/subsegmental level, with 75% showing distal tortuous vessels. None of the heterozygous variant carriers with CTEPH exhibited the string-of-beads pattern or elongated stenosis. Homozygous variant carriers with PPS showed the string-of-beads pattern, elongated stenosis, and distal tortuous vessels without webs/bands lesions. CONCLUSIONS: A subset of patients diagnosed with CTEPH (7.1%) carried the heterozygous RNF213 p.Arg4810Lys variant. Clinical and angiographic characteristics of heterozygous variant carriers were not remarkably different from those of noncarriers of CTEPH. However, both heterozygous variant carriers with CTEPH and homozygous variant carriers with PPS showed tortuous vessels on angiography.

Pulmonary Hypertension Induced by Right Pulmonary Artery Occlusion: Hemodynamic Consequences of Bmpr2 Mutation.

BACKGROUND: The primary genetic risk factor for heritable pulmonary arterial hypertension is the presence of monoallelic mutations in the BMPR2 gene. The incomplete penetrance of BMPR2 mutations implies that additional triggers are necessary for pulmonary arterial hypertension occurrence. Pulmonary artery stenosis directly raises pulmonary artery pressure, and the redirection of blood flow to unobstructed arteries leads to endothelial dysfunction and vascular remodeling. We hypothesized that right pulmonary artery occlusion (RPAO) triggers pulmonary hypertension (PH) in rats with Bmpr2 mutations. METHODS AND RESULTS: Male and female rats with a 71 bp monoallelic deletion in exon 1 of Bmpr2 and their wild-type siblings underwent acute and chronic RPAO. They were subjected to full high-fidelity hemodynamic characterization. We also examined how chronic RPAO can mimic the pulmonary gene expression pattern associated with installed PH in unobstructed territories. RPAO induced precapillary PH in male and female rats, both acutely and chronically. Bmpr2 mutant and male rats manifested more severe PH compared with their counterparts. Although wild-type rats adapted to RPAO, Bmpr2 mutant rats experienced heightened mortality. RPAO induced a decline in cardiac contractility index, particularly pronounced in male Bmpr2 rats. Chronic RPAO resulted in elevated pulmonary IL-6 (interleukin-6) expression and decreased Gdf2 expression (corrected P value<0.05 and log2 fold change>1). In this context, male rats expressed higher pulmonary levels of endothelin-1 and IL-6 than females. CONCLUSIONS: Our novel 2-hit rat model presents a promising avenue to explore the adaptation of the right ventricle and pulmonary vasculature to PH, shedding light on pertinent sex- and gene-related effects.

Estimating pulmonary arterial remodeling via an animal-specific computational model of pulmonary artery stenosis.

Pulmonary artery stenosis (PAS) often presents in children with congenital heart disease, altering blood flow and pressure during critical periods of growth and development. Variability in stenosis onset, duration, and severity result in variable growth and remodeling of the pulmonary vasculature. Computational fluid dynamics (CFD) models enable investigation into the hemodynamic impact and altered mechanics associated with PAS. In this study, a one-dimensional (1D) fluid dynamics model was used to simulate hemodynamics throughout the pulmonary arteries of individual animals. The geometry of the large pulmonary arteries was prescribed by animal-specific imaging, whereas the distal vasculature was simulated by a three-element Windkessel model at each terminal vessel outlet. Remodeling of the pulmonary vasculature, which cannot be measured in vivo, was estimated via model-fitted parameters. The large artery stiffness was significantly higher on the left side of the vasculature in the left pulmonary artery (LPA) stenosis group, but neither side differed from the sham group. The sham group exhibited a balanced distribution of total distal vascular resistance, whereas the left side was generally larger in the LPA stenosis group, with no significant differences between groups. In contrast, the peripheral compliance on the right side of the LPA stenosis group was significantly greater than the corresponding side of the sham group. Further analysis indicated the underperfused distal vasculature likely moderately decreased in radius with little change in stiffness given the increase in thickness observed with histology. Ultimately, our model enables greater understanding of pulmonary arterial adaptation due to LPA stenosis and has potential for use as a tool to noninvasively estimate remodeling of the pulmonary vasculature.

Pulmonary Artery Stent Implantation.

Pulmonary artery stent implantation has become integral in the treatment of pulmonary artery stenosis and is probably the most efficacious therapy for these lesions. Advancements in technology involving stent design and the equipment used for stent delivery have made this procedure much safer and more effective. Strategies to mitigate and successfully treat adverse events related to pulmonary artery stent implantation are reasonably well-established. Pulmonary artery stent implantation remains one of the most complex and technically challenging of congenital cardiac interventions.

Simultaneous stent implantation for pulmonary artery bifurcation stenosis in infants.

OBJECTIVES: Pulmonary artery (PA) bifurcation stenosis often requires simultaneous stent placement, which may be technically challenging. Limited data exist regarding this practice in infants. We aim to report the procedural outcomes and safety of bifurcation stent placement in infants. METHODS: We performed a single-center retrospective review of infants younger than 12 months who underwent simultaneous stent placement for PA bifurcation stenosis from January 1, 2001 through December 31, 2019. RESULTS: Seventeen infants underwent simultaneous PA bifurcation stent placement. The median age was 6.4 months (1.1-10.1 months), and weight was 5.8 kg (3-10.6 kg). Nine (52.9%) patients had had prior PA intervention. Most stents were placed in central PAs (28, 82.4%), followed by lobar branches (6, 17.6%). All patients received pre-mounted stents. The peak gradient across each branch decreased from 47.4 ± 16 to 18.7 ± 13 mm Hg (P less than .0001). The right ventricle to systemic systolic pressure ratio decreased from systemic (1.0 ± 0.3) to just over half systemic (0.58 ± 0.2) (P = .0001). The minimum vessel diameter increased from 3.6 ± 1.5 to 6.0 ± 1.9 mm (P less than .0001). There were 4 (23.5%) patients with high severity adverse events. There were no procedure-related deaths. The median follow-up period was 83.8 months (5.3 months-19.4 years). All patients had subsequent PA re-intervention at a median time of 8.1 months (2.9 months-8.8 years), and median time to re-operation was 19.1 months (2.9 months-7.5 years). CONCLUSIONS: Simultaneous PA stent placement is an effective strategy for relief of bifurcation stenosis in infants. Future transcatheter interventions are necessary to account for patient growth, but may delay the need for re-operation.

Results of the multicenter early feasibility study (EFS) of the Renata Minima stent as treatment for branch pulmonary artery stenosis and coarctation of aorta in infants.

BACKGROUND: Stent implantation has become standard of care in older children and adults for treatment of branch pulmonary artery stenosis (BPAS) and coarctation aorta (CoAo). There are no stents approved or available for infants that have the potential to be dilated to adult diameters. The Minima stent was designed to fulfill this unmet need. METHODS: Multicenter, prospective, nonrandomized early feasibility study evaluating safety and effectiveness of the Minima stent for treatment of BPAS and CoAo. Primary endpoints included: (1) successful deployment across lesion, (2) stenosis relief defined by an increase in angiographic diameter of >50% and (3) freedom from stent explant, embolization or migration at 30 days and 6 months. RESULTS: Between 2/2022 and 5/2022, 10 pts underwent Minima stent implantation with a median age and weight of 9 months (4-43 months) and 7.6 kg (5.1-16.9 kg). Procedural success and predefined stenosis relief was achieved in all cases (CoAo [n = 4], BPAS [n = 6]). Adverse events occurred in 3 pts: transient diminished lower extremity pulse (n = 2), distal stent on-balloon displacement successfully managed in the catheterization suite (n = 1). There were no deaths or major adverse events. All patients were free from stent explant and migration at 30 days and 6 months with no evidence for significant restenosis at latest follow-up. CONCLUSIONS: Implantation of the Renata Minima stent was safe and effective for the treatment of BPAS and CoAo in this small cohort of infants and young children during early follow-up. Based on these early results, an expanded study with longer follow-up is warranted.

The impact of unilateral pulmonary artery stenosis on right ventricular to pulmonary arterial coupling in patients with transposition of the great arteries.

BACKGROUND: Unilateral pulmonary artery (PA) stenosis is common in the transposition of the great arteries (TGA) after arterial switch operation (ASO) but the effects on the right ventricle (RV) remain unclear. AIMS: To assess the effects of unilateral PA stenosis on RV afterload and function in pediatric patients with TGA-ASO. METHODS: In this retrospective study, eight TGA patients with unilateral PA stenosis underwent heart catheterization and cardiac magnetic resonance (CMR) imaging. RV pressures, RV afterload (arterial elastance [Ea]), PA compliance, RV contractility (end-systolic elastance [Ees]), RV-to-PA (RV-PA) coupling (Ees/Ea), and RV diastolic stiffness (end-diastolic elastance [Eed]) were analyzed and compared to normal values from the literature. RESULTS: In all TGA patients (mean age 12 ± 3 years), RV afterload (Ea) and RV pressures were increased whereas PA compliance was reduced. RV contractility (Ees) was decreased resulting in RV-PA uncoupling. RV diastolic stiffness (Eed) was increased. CMR-derived RV volumes, mass, and ejection fraction were preserved. CONCLUSION: Unilateral PA stenosis results in an increased RV afterload in TGA patients after ASO. RV remodeling and function remain within normal limits when analyzed by CMR but RV pressure-volume loop analysis shows impaired RV diastolic stiffness and RV contractility leading to RV-PA uncoupling.

Numerical investigation of quantitative pulmonary pressure ratio in different degrees of stenosis.

BACKGROUND: Pulmonary artery stenosis endangers people's health. Quantitative pulmonary pressure ratio (QPPR) is very important for clinicians to quickly diagnose diseases and develop treatment plans. OBJECTIVE: Our purpose of this paper is to investigate the effects of different degrees (50% and 80%) of pulmonary artery stenosis on QPPR. METHODS: An idealized model is established based on the normal size of human pulmonary artery. The hemodynamic governing equations are solved using fluid-structure interaction. RESULTS: The results show that the QPPR decreases with the increase of stenosis degree, and it is closely related to the pressure drop at both ends of stenosis. Blood flow velocity and wall shear stress are sensitive to the stenosis degree. When the degree of stenosis is 80%, the amplitude of changes of blood flow velocity and wall shear stress at both ends of stenosis is lower. CONCLUSIONS: The results suggest that the degree of pulmonary artery stenosis has a significant impact on QPPR and hemodynamic changes. This study lays a theoretical foundation for further study of QPPR.

Successful Anesthesia Management of Pediatric Living Donor Liver Transplant With Mild Bilateral Pulmonary Artery Stenosis Due to Alagille Syndrome: A Case Report.

Alagille syndrome is an autosomal-dominantinherited disease characterized by intrahepatic bile duct involvement, congenital heart disease, eye anomalies, skeletal and central nervous system involvement, kidney anomalies, and facial appearance. Liver transplant is the only treatment option for patients with end-stage liver disease and Alagille syndrome. Bilateral peripheral pulmonary artery stenosis is a contraindication for liver transplant due to high mortality, and the decision for liver transplant in patients with bilateral peripheral pulmonary artery stenosis is extremely challenging for anesthesiologists andtransplant surgeons.Wepresent a 2-year-oldfemale patient with successful anesthetic management of a pediatric living donor liver transplant with mild bilateral pulmonary artery stenosis, mild aortic stenosis, and mitral regurgitation due to Alagille syndrome. Anesthesiologists should know the underlying pathophysiological condition and perform a comprehensive preoperative evaluation to determine the correct anesthesia plan in patients with Alagille syndrome who will undergo liver transplants to treat multiple system disorders. Successful perioperative management of Alagille syndrome requires effective communication and collaboration between specialists through a multidisciplinary team approach.

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.