Pulmonary Artery Stenting Research Articles

Treatment of pulmonary artery pseudoaneurysms and stenosis with balloon-expandable stents.

We describe our use of balloon-expandable stents in pulmonary arteries for a variety of indications. This is an endovascular technique that provides an alternative treatment option to treat some forms of complex pulmonary artery disease when standard surgical or other endovascular options are not possible. This case series describes the successful treatment of four patients with different pulmonary artery diseases. Indications for stent placement include multiple broad-necked pulmonary artery pseudoaneurysms, symptomatic malignant pulmonary artery narrowing and post-surgical iatrogenic pulmonary artery stenosis. No stent-related complication had been identified from 3 months to 4 years of follow-up. All surviving patients have experienced sustained symptomatic improvement.

CARC3: Characterizing Audio Traits of Various Systemic to Pulmonary Connections in Ductal Dependent Infants

Background: Infants with congenital heart disease who have insufficient systemic or pulmonary blood flow require a connection between the systemic and pulmonary vasculature. There are four types of shunts: right ventricle to pulmonary artery (Sano), Blalock-TaussigThomas (BTTS), central, and ductal arterial stent (DAS). They have a high incidence of mortality and unplanned interventions. Machine learning algorithms evaluate a shunt murmur recorded on a digital stethoscope to differentiate the audio features of various shunts. Methods: A 3M Littman Electronic Stethoscope acquired phonocardiogram (PCG) data from infants with shunt placement on post-operative days 0, 1, 2, 7, 14, discharge and day of shunt take-down, as well as, when imaging (echo, CT, catheterization) was performed. Patient demographics and clinical outcomes noted. A wavelet decomposition algorithm denoised the PCG data with a bandpass filter ranging from 20 to 2000 Hz and then segmented into S1 and S2. One hundred and fifteen audio features, comprising temporal, spectral, statistical, and bandpower domains were extracted from the waveforms. A statistical algorithm including ANOVA, Kruskal Wallis and pairwise comparison tests detected 33 total features showing a statistically significant difference in means (alpha = 0.05). Results: Thirteen subjects (BTTS (n=3), DAS (n=2), and Sano (n=8)) who had second stage palliation were analyzed using the two most recent recordings prior to shunt takedown. Principal component analysis (Figure 1) and tdistributed stochastic neighbor embedding (Figure 2) visualization techniques indicate a separation among shunt types. Conclusion: Audio signatures could exist based on shunt type characteristics and may lead to a novel non-invasive tool to monitor shunt health. Figure 1. Principal Component Analysis (PCA) indicating a separation in BTTS, Sano, and PDA shunt types from selected recordings. Figure 2. t-distributed stochastic neighbor embedding (tSNE) indicating a separation in BTTS, Sano, and PDA shunt types from selected recordings.

Partially open stent after balloon catheter iatrogenic perforation. How to solve this complication using a novel technique? The Mij-Her technique.

Complications related to pulmonary artery stenting are potentially life-threatening. We reported a novel technique of how to achieve the introduction of a partial dilated stent into a long sheath using a snare in the event of a iatrogenic perforation of a balloon catheter.There are no publications of similar techniques describing successful resolution of this type of complication.

Branch pulmonary artery stent angioplasty in infants less than 10 kg

BackgroundBranch pulmonary artery (PA) Stenting is an established strategy for PA stenosis in older children and adults. Its use in infants is less well established. We describe our experience of branch PA Stenting in infants <10 kg. MethodRetrospective chart review of infants <10 kg who underwent PA Stenting at The Children's Hospital, Westmead between 2010 and 2020. Pre and post-procedural angiograms were reviewed to determine PA size. Technical procedural success was defined as >50% increase in PA diameter. Procedural complications and need for PA re-intervention were ascertained. ResultsForty-one children (age 7.6 months, IQR 2.4–9.8 months, weight 5.9 ± 2.2 kg) had 43 primary Stent implantations (10/43 intraoperative versus 33/43 transcatheter; left pulmonary artery [LPA] 25/43, right pulmonary artery [RPA] 8/43 and bilateral 10/43). Diagnoses were tetralogy of Fallot (27%), hypoplastic left heart syndrome (24%), truncus arteriosus (12%), transposition of the great arteries (7%), other single ventricle (10%) and other biventricular (20%). 40/41 (98%) had undergone a cardiac intervention in the preceding 31 days, [IQR 1–181], with 17/41 having prior branch PA intervention. 14/41 patients had urgent Stenting. There were 2 minor and 1 major complications with no procedural mortality. LPA (LPApre 2.3 ± 1.0 × 2.2 ± 1.2 mm versus LPApost 5.2 ± 1.3 × 5.0 ± 1.7 mm, p < 0.01) and RPA (RPApre 2.5 ± 0.8 × 1.9 ± 0.8 mm versus RPApost 4.9 ± 1.0 × 4.1 ± 1.0 mm, p < 0.01) calibre increased post Stenting. 20/41 required branch PA reintervention (time to reintervention 13.6 months [IQR 8.2–29.3]. ConclusionsBranch PA Stenting is effective and safe in infants <10 kg with expected high rates of reintervention. Urgent PA Stenting provides relief of early post-operative haemodynamic compromise.

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

BackgroundDespite 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 ResultsIsolated 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.ConclusionsIn 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.

EP080: A rare case of mosaic trisomy 15 with chylothorax

eP080: A rare case of mosaic trisomy 15 with chylothorax

Anaesthetic management of a dog with severe pulmonary stenosis and R2A right coronary artery anomaly undergoing placement of a hybrid transventricular pulmonary stent

AbstractA 7‐month‐old, 12.2 kg, male, neutered, English bulldog with severe pulmonary stenosis and R2A right coronary artery anomaly was anaesthetised for placement of hybrid right ventricle to pulmonary artery stent. An alfentanil bolus (10 μg/kg intravenously) was used as premedication. Anaesthesia was induced with midazolam (0.2 mg/kg) and etomidate (1 mg/kg) intravenously, and maintained with sevoflurane in 100% oxygen. Perioperative analgesia was achieved combining locoregional techniques with intravenous analgesics. The main intraoperative complications were hypotension, bradycardia, ventricular premature complexes, ST‐segment depression and transient hypoxaemia. Lidocaine constant‐rate infusion (50 μg/kg/min) and magnesium sulphate constant‐rate infusion (5 mg/kg/h) were used to prevent arrhythmias during the cardiac manipulations and stent placement. Hypotension was treated with dobutamine and noradrenaline constant‐rate infusion. The use of different drugs and anaesthetic techniques (balanced anaesthesia) provided antinociception, muscle relaxation and appeared to be effective in preventing major cardiovascular complications.

The incidence of recurrent laryngeal nerve injury resulting in vocal cord paralysis following interventional congenital catheterisation procedures.

Recurrent laryngeal nerve injury leading to vocal cord paralysis is a known complication of cardiothoracic surgery. Its occurrence during interventional catheterisation procedures has been documented in case reports, but there have been no studies to determine an incidence. To establish the incidence of left recurrent laryngeal nerve injury leading to vocal cord paralysis after left pulmonary artery stenting, patent ductus arteriosus device closure and the combination of the procedures either consecutively or simultaneously. Members of the Congenital Cardiovascular Interventional Study Consortium were asked to perform a retrospective analysis to identify cases of recurrent laryngeal nerve injury after the aforementioned procedures. Twelve institutions participated in the analysis. They also contributed the total number of each procedure performed at their respective institutions for statistical purposes. Of the 1337 patients who underwent left pulmonary artery stent placement, six patients (0.45%) had confirmed vocal cord paralysis. 4001 patients underwent patent ductus arteriosus device closure, and two patients (0.05%) developed left vocal cord paralysis. Patients who underwent both left pulmonary artery stent placement and patent ductus arteriosus device closure had the highest incidence of vocal cord paralysis which occurred in 4 of the 26 patients (15.4%). Overall, 92% of affected patients in our study population had resolution of symptoms. Recurrent laryngeal nerve injury is a rare complication of left pulmonary artery stent placement or patent ductus arteriosus device closure. However, the incidence is highest in patients undergoing both procedures either consecutively or simultaneously. Additional research is necessary to determine contributing factors that might reduce the risk of recurrent laryngeal nerve injury.

Effectiveness of Bilateral Pulmonary Artery Banding in Patients with Hypoplastic Left Heart Syndrome and Congenital Heart Defects with A Functional Single Ventricle: A Single-Center Retrospective Study

Background: Bilateral banding of the branches of the pulmonary artery in patients with hypoplastic left heart syndrome (HLHS) and other duct dependent critical neonatal heart malformations can significantly reduce the incidence of severe complications in the postoperative period, especially in severely unstable patients. In our study we compared different surgical techniques of bilateral pulmonary artery banding (PAB) in respect to their success in balancing systemic and pulmonary blood flow. Methods: We included 44 neonates with a HLHS and congenital heart diseases (CHD) with a functional single ventricle underwent a hybrid operation: bilateral PAB and patent ductus arteriosus stenting. The hybrid surgery for method No. 1 is performed as a one-stage procedure, together with patent ductus arteriosus (PDA) stenting. After median sternotomy, two Gore-Tex 1–2 mm wide bands with a diameter of 3–3.5 mm are put. When we apply method No. 2 then the thread is used to create bands. Method No. 3 is distinguished by intraoperative assessment of blood flow at the site of narrowing of the branches of the pulmonary artery and optional stenting of the PDA. The cuff for banding is made of Gore-Tex tubing. Effectiveness when applying method Nos. 1 and 2 is assessed by the change in invasive blood pressure and oxygen saturation after narrowing of the branches of the pulmonary artery. Also, with these techniques PDA stenting by inserting the introducer via pulmonary artery trunk is performed. Results: HLHS with mitral or aortic valve atresia or both was present in 19 patients (43.1%), with severe left heart obstruction resulting in PDA dependent systemic circulation in 16 babies (36.4%). CHD with single ventricle physiology occurred in 9 patients (20.5%). 14 babies (31.8%) undergo the procedure following the method No. 1, 8 patients (18.2%) method No. 2 and 22 patients (50%) method No. 3. Qp/Qs = 1/1 was achieved in 30 patients (30/44, 68.1%): as a result of the method No. 1 was achieved in 5 patients (5/14, 35.7%), method No. 2 in 4 patients (4/8, 50%), method No. 3 in 21 patients (21/22, 95.5%). Multivariate regression analysis revealed that method No. 3 significantly increases the chances of hemodynamic efficacy operations (OR = 35.0; p = 0.005; CI (95%) 3–411.5). Conclusion: Application of the operation technique No. 3 in combination with the intraoperative assessment of blood flow parameters at the site of banding of the branches of the pulmonary artery are the most optimal criteria for achieving Qp/Qs = 1/1. If there are signs of restriction at the level of the foramen ovale, atrioseptostomy should be done in the second stage after bilateral pulmonary banding.

Heart transplantation for patients with single ventricle physiology.

BackgroundThere is a growing population of palliated and unpalliated single ventricle physiology patients for whom heart transplantation is the only treatment option available. There is a paucity of reports of heart transplantation in this challenging and growing subset of patients from our part of the world. The purpose of the article is to briefly review our experience in the subgroup and compare it with the available literature.MethodsThis was a single-institution retrospective observational study of 16 patients with single ventricle physiology who were transplanted between 2016 and 2019 and their outcomes. The study groups were divided into those with ventricular dysfunction (group 1), who fare substantially better than those with normal ventricular function (group 2) whose short-term outcomes were poorer. Worsening cyanosis, poor candidature for completion Fontan procedure due to severe atrioventricular valve regurgitation or pulmonary artery anatomy, protein-losing enteropathy, plastic bronchitis, and worsening systemic venous congestion are indications in those with normal ventricular function.ResultsPatients with ventricular dysfunction as the main indication had excellent early survival with no early mortality compared to 40% mortality in patients with normal ventricular function. Patients who survived to leave the hospital had however similar long-term outcomes. Two patients with protein-losing enteropathy resolved completely by one month. Normal ventricular function, pulmonary artery stenting, early Fontan failure (6 months), ascites, and need for desensitization were risk factors for early mortality. After the early acute phase of increased risk, the mortality risk plateaued off.ConclusionTransplantation in patients with single ventricle and ventricular dysfunction can be offered with a good early and late outcome. There is a need to have multi-institutional and multi-disciplinary collaboration along with work in basic sciences to better understand the effects of failed Fontan physiology with normal ventricular function.

Emergency Department Presentation and Outcome of Children With Cyanotic Congenital Heart Diseases.

ObjectiveThis study aimed to assess the outcome and see the spectrum of presenting symptoms of children with cyanotic congenital heart diseases (CHDs) admitted through the emergency department in Lady Reading Hospital (LRH) in Peshawar, Pakistan.Materials and methodsThis cross-sectional study included 104 children with cyanotic CHD admitted through the emergency department in the pediatric cardiology unit of LRH from February 2019 to January 2020. Diagnosis of cyanotic CHD was confirmed through two-dimensional echocardiography. Patients were treated according to standard protocols for their presenting symptoms. The data were analyzed using Statistical Package for the Social Sciences (SPSS), version 20.0 (IBM Corp., Armonk, NY) and frequencies were expressed as percentages.ResultsThe study included 65 male cases (62.5%) and 39 female cases (37.5%), and participant ages ranged from 10 days to 15 years (mean, 2.7 ± 3.4 years). Of 104 patients, 70 presented with cyanotic spells (84.5%), 53 with fever (10.7%), 28 with respiratory distress (26.5%), 11 with loose stools (10.5%), 10 with hemiplegia (9.6%), and eight with seizures (7.6%). Pneumonia was a precipitating factor in 13 patients (12.5%), infective endocarditis in 12 patients (11%), gastroenteritis in 11 (11%), brain abscess and cerebrovascular accidents in seven patients each (6% each), meningitis in six patients (6%), and tuberculous pericardial effusion in one patient (<1%). The primary CHD was tetralogy of Fallot (TOF) in 52 patients, tricuspid atresia in 14 patients, pulmonary atresia in 13 patients, double outlet right ventricle in 10 patients, transposition of great arteries (TGA) in seven patients, and total anomalous pulmonary venous return (TAPVR), truncus arteriosus, congenitally corrected TGA, and critical pulmonary stenosis in two patients each. Twenty-six patients received treatment of the acute problem and instructions for follow-up monitoring. Twelve patients died during their hospital stay, and three left against medical advice. Fifteen patients received patent ductus arteriosus stenting, and six received right ventricular outflow tract stenting. One patient received a Blalock-Taussig (BT) shunt stent, and one received a left pulmonary artery stent. Two patients received a balloon pulmonary valvotomy, and one received pericardial effusion drainage. Eleven patients received surgical correction of TOF, 11 received surgical correction for BT shunt, four received surgical correction for brain abscess drainage, and two received TAPVR repair.ConclusionTOF was the most common cyanotic heart disease in our study. Cyanotic spells or increased cyanosis was the most common presenting concern. Cyanotic CHDs present with variable extracardiac signs and symptoms in emergencies. Appropriate assessment, immediate management of the acute problem, and timely intervention or surgical management result in good outcomes.

Unilateral branch pulmonary artery stenting in tetralogy of fallot improves ventricular function

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): NIHR Background Pulmonary artery stenosis (PAS) occurs commonly in patients with tetralogy of fallot (ToF). Cardiac function and especially left ventricular longitudinal strain has been identified as an important prognostic factor for long term survival in ToF. The clinical relevance of unilateral PAS to long-term bi-ventricular function is poorly understood. Purpose We sought to evaluate the effect of resolving unilateral pulmonary artery obstruction on right and left ventricular performance. Methods We prospectively included 40 patients with TOF between 2016 and 2020, 20 who underwent unilateral PAS stenting and as comparison 20 who underwent surgical pulmonary valve replacement (PVR). MRI data was acquired during routine clinical care before and around 6-12 months after the procedure. 4 PAS patients attended additional research scans acquiring ventricular 4D flow MRI data. 4D flow MRI data was compared to the average kinetic energy curve of 10 age-matched healthy volunteers. Results Of the 20 patients undergoing PAS, 2 also underwent percutaneous PVR and were excluded from the comparison analysis. All patients in the PAs group showed an improvement in branch PA flow differential post procedure. Patients undergoing PAS were younger than those undergoing PVR (median 12 vs 19 years, p &amp;lt; 0.001). Other baseline anatomical and functional parameters including right ventricular (RV) volume indexed to body surface are (RVEDV/BSA) were comparable (pre PAS median 151 [122,170] vs pre PVR 162 [140,191]; p = 0.217). While in the PVR group the right ventricular volumes reduced in both end-diastole and end-systole, in the PAS group RV function improved due to reduced end-systolic volume with largely stable end-diastolic volumes. Changes in the left ventricle (LV) were even more interesting. In the PVR group ejection fraction improved due to an increase in end-diastolic volume with no improvement in ventricular longitudinal strain. In contrast, in the PAS group LV ejection fraction improved by a reduction in end-systolic volume and the PAS group showed a small but significant improvement in LV longitudinal strain. In addition, ¾ patients undergoing 4D flow MRI assessment showed LV kinetic energy curve more similar to the healthy volunteer averaged LV kinetic energy curve after PAS. The 4th patient already had a near normal LV kinetic energy curve prior to PAS. Conclusion Unilateral PAS does not alter RV end-diastolic volumes but improves RV function. LV ejection fraction improvement is similar to that seen after PVR, but importantly PAS also improved LV longitudinal strain. This suggests that PAS might positively influence long term morbidity and mortality risk in ToF patients, but a larger multi-centre long term follow-up study is needed to confirm this.

Symptomatic esophageal retention of a patency capsule due to extraesophageal compression from pulmonary artery stent grafts.

The authors declare no conflict of interests.

Duct-dependent cyanotic neonates with patent ductus arteriosus stenting pose a unique challenge for the next stage of surgical intervention

Objective To study the role of patent ductus arteriosus (PDA) stenting in the management of single-ventricle patients and the surgical difficulties facing the surgeons in the next stages of surgical procedures. Background Thirty consecutive neonates with cyanotic duct-dependent lesions were initially palliated with (PDA) stenting in our center. Eighteen of them had undergone one or more surgical procedures. We retrospectively assessed the indexed growth of pulmonary arteries (PA) over a period of time and the requirement of further rehabilitation of PAs in these patients. Patients and methods From January 2014 to December 2018, 30 neonates with cyanotic congenital heart diseases underwent PDA stenting as initial palliation; 60% were ventilated before the procedure, which resulted in 100% success. All patients were followed up regularly by monitoring of PA size imaging. Eighteen patients of this group underwent further surgical procedures. Results Ninety percent of the neonates had stenosis of the PA branches before PDA stenting. The indexed PA branch size was significantly smaller, which increased after stenting of PDA. At the time of the next surgical procedures (Glenn, etc.), stent division/ligation was required in addition to PA plasty in 90% of patients. Conclusions PDA stenting provides efficient palliation in cyanotic neonates. Despite the origin of stenosis, the stent allowed growth in the size of both PAs. However, the majority required surgical augmentation and further stenting of PAs in the mid-term follow-up.

Outcomes of Venus P-valve for dysfunctional right ventricular outflow tracts from Indian Venus P-valve database.

Background :Balloon-expandable pulmonary valves are usually not suitable for dilated native outflow tracts.Methods :Indian Venus P-valve registry was retrospectively analyzed for efficacy, complications, and midterm outcomes. Straight valve was used in prestented conduits in patients with right ventricular pressure above two-thirds systemic pressure and/or right ventricular dysfunction. Flared valve 1–4 mm larger than balloon waist was used in native outflow in symptomatic patients, large ventricular volumes, and ventricular dysfunction.Objectives :A self-expanding porcine pericardial Venus P-valve is available in straight and flared designs..Results :Twenty-nine patients were included. Straight valve was successful in all seven conduits, reducing gradients significantly, including one patient with left pulmonary artery (LPA) stent. Flared valve was successfully implanted in 20 out of 22 native outflow tracts. Sharp edges of the older design contributed to two failures. Complications included two migrations with one needing surgery, endocarditis in one, insignificant wire-frame fractures in three, and groin vascular complication in one patient. There were no deaths or valve-related reinterventions at a mean follow-up of 47.8 ± 24.5 months (1–85 months). Modifications of technique succeeded in three patients with narrow LPA. There was significant improvement in symptoms, right ventricular volume, and pulmonary regurgitant fraction.Conclusion :Straight and flared Venus P-valves are safe and effective in appropriate outflow tracts. Straight valve is an alternative to balloon-expandable valves in stenosed conduits. Flared valve is suitable for large outflows up to 34 mm, including patients with LPA stenosis. Recent design modifications may correct previous technical failures. Studies should focus on durability and late complications.

Bridging the Gap and Moving the Needle

Bleiweis and colleagues1 should be commended on their series of high-risk infants with hypoplastic left heart syndrome whom they courageously chose to bridge to transplant with the combination of pulsatile ventricular assist device (VAD) implantation and branch pulmonary artery banding and arterial ductal stenting. Certainly the outcomes speak volumes. With 9 patients in the series, 5 are well at home after transplant, 1 remains on support, and 3 died, with the shortest duration of support of 56 days.

Y-shaped Bifurcated Graft to Pulmonary Arteries After Arterial Switch Operation

Pulmonary artery stenosis is a frequent complication after arterial switch operation. This case study presented a complex pulmonary artery stenosis initially treated with bilateral pulmonary artery stenting. The patient was found to have aortic valve endocarditis and recurrent pulmonary artery stenosis. The aortic valve was replaced and the pulmonary valve was repaired, followed by interposition of a Y-shaped graft from the sinotubular junction to both pulmonary arteries. The patient had an uneventful recovery and was discharged home asymptomatic after endocarditis antibacterial treatment.

Fontan-Associated Anatomical Variants and Hepatic Fibrosis.

We hypothesized that a relationship between post-Fontan hepatic fibrosis and anatomical variants might exist. Attempting to limit confounding variables, we analyzed data from living, stable, post-extracardiac Fontan patients who underwent cardiac catheterization and transvenous hepatic biopsy procedures between March 2012 and June 2020. We identified 120 patients who met the inclusion criteria. Of the 120, 35 (29%) had pulmonary artery stents. For the 35 with pulmonary artery stents, the average total fibrosis score was 3.2 ± 1.9 and the fibrosis progression rate was 0.36 ± 0.33, and for those with no pulmonary artery stents, the total fibrosis score was 2.6 ± 1.8 and the fibrosis progression rate was 0.27 ± 0.33 (P = .13 and P = .11, respectively). Of the 120, 65 had functional univentricles of right ventricular type. Of these 65, 27 had pulmonary artery stents. For the 27 with pulmonary artery stents, the average total fibrosis score was 3.4 ± 1.8 and the average fibrosis progression rate was 0.39 ± 0.30, and for the 38 without pulmonary artery stents, the average fibrosis score was 2.3 ± 1.5 and the average fibrosis progression rate was 0.23 ± 0.21 (P = .01 for comparison of both values). This study's findings suggest that a post-extracardiac Fontan with a functional univentricle of right ventricular type plus a pulmonary artery stent may have more advanced liver pathology than those without a pulmonary artery stent at similar Fontan duration years and ages at liver biopsy.

Stent interventions for pulmonary artery stenosis improve bi-ventricular flow efficiency in a swine model

BackgroundBranch pulmonary artery (PA) stenosis (PAS) commonly occurs in patients with congenital heart disease (CHD). Prior studies have documented technical success and clinical outcomes of PA stent interventions for PAS but the impact of PA stent interventions on ventricular function is unknown. The objective of this study was to utilize 4D flow cardiovascular magnetic resonance (CMR) to better understand the impact of PAS and PA stenting on ventricular contraction and ventricular flow in a swine model of unilateral branch PA stenosis.Methods18 swine (4 sham, 4 untreated left PAS, 10 PAS stent intervention) underwent right heart catheterization and CMR at 20 weeks age (55 kg). CMR included ventricular strain analysis and 4D flow CMR.Results4D flow CMR measured inefficient right ventricular (RV) and left ventricular (LV) flow patterns in the PAS group (RV non-dimensional (n.d.) vorticity: sham 82 ± 47, PAS 120 ± 47; LV n.d. vorticity: sham 57 ± 5, PAS 78 ± 15 p < 0.01) despite the PAS group having normal heart rate, ejection fraction and end-diastolic volume. The intervention group demonstrated increased ejection fraction that resulted in more efficient ventricular flow compared to untreated PAS (RV n.d. vorticity: 59 ± 12 p < 0.01; LV n.d. vorticity: 41 ± 7 p < 0.001).ConclusionThese results describe previously unknown consequences of PAS on ventricular function in an animal model of unilateral PA stenosis and show that PA stent interventions improve ventricular flow efficiency. This study also highlights the sensitivity of 4D flow CMR biomarkers to detect earlier ventricular dysfunction assisting in identification of patients who may benefit from PAS interventions.

Branch Pulmonary Artery Stent Angioplasty in Children Less Than 10kg

Branch pulmonary artery (PA) stenting is an established strategy for PA stenosis in older children/adults. Its use in infants is less well established. We describe our experience of branch PA stenting in infants <10 kg.