Pulmonary Artery Stenting Research Articles

Pulmonary artery stents in the recent era

Long-term follow-up after stent dilation of native and acquired pulmonary artery stenosis is scarce in the pediatric population. Most cohorts include a myriad of anatomies and associated conditions. In order to establish objective performance criteria, we performed a retrospective review of all patients who underwent unilateral pulmonary artery stenting in biventricular physiology at three centers from June 2006 to June 2011. Fifty-eight patients received 60 stents with Palmaz Genesis stent used most commonly (78%). Average age at implantation was 10.4 ± 10.3 years and weight 31.6 ± 21.8 kg. The immediate success rate was 98%, with improvement in minimal diameter from 5.1 ± 2 cm to 10.6 ± 3 cm (P < 0.01). There were 10 complications (7 major and 3 minor) and no acute mortality. One-year follow-up studies were available in 48 patients (83%), including echocardiogram (60%), catheterization (28%), MRI (29%), and lung perfusion (31%). Follow-up echocardiogram showed mild increase in stent gradient, from 5.7 ± 6.7 mm Hg post-procedure to 17.1 ± 11.7 mm Hg. Follow-up catheterization showed no significant change in minimal stent diameter (8.8 ± 2.6 to 7.8 ± 2.3 mm), gradient (7.7 ± 8.4 to 12.6 ± 12.2 mm Hg), or right ventricular pressures (43.7 ± 9 to 47.7 ± 10.5 mm Hg). Nine patients (16%) underwent scheduled stent redilation over a period of 12 days to 25 months. In conclusion, stent implantation shows excellent immediate and 1-year follow-up results with maintenance of improved caliber of the stented vessel and lowered right ventricular systolic pressures.

Extracorporeal Membrane Oxygenation in Single Ventricle Lesions Palliated Via the Hybrid Approach.

Describing outcomes for children with hypoplastic left heart syndrome (HLHS) undergoing hybrid palliation (pulmonary artery band and stent placement in the patent ductus arteriosus) requiring extracorporeal membrane oxygenation (ECMO) support for cardiorespiratory failure. We reviewed the Extracorporeal Life Support Organization database for all patients with a diagnosis of an HLHS undergoing hybrid stage 1 palliation supported with ECMO and those patients with hybrid palliation supported with ECMO after comprehensive stage 2 palliation. Patients were identified using a combination of International Classification of Diseases, Ninth Revision and registry diagnosis and procedure codes. We report survival to hospital discharge and ECMO complications. We identified 44 patients with HLHS requiring ECMO following stage 1 hybrid approach. Median age at cannulation was 13.5 days. Only 16% survived to hospital discharge. In all, 20 (50%) patients had a cardiac arrest prior to going onto ECMO and for 3 (19%) patients, ECMO was initiated during cardiopulmonary resuscitation. Overall survival for ECMO support in patients with HLHS palliated via the hybrid approach is very poor (16%) and is worse than 31% survival reported for ECMO after conventional stage 1 palliation. The reasons for these poor outcomes require further investigation.

Outcomes of patients who underwent staged repair for pulmonary atresia with ventricular septal defects and major aorto-pulmonary collateral arteries at Southampton University Hospital, United Kingdom

Objective: To assess the long-term outcomes of multistage surgical approach in 18 surviving patients in areas of mortality, requirement for postoperative interventional cardiac catheterization, saturations on air, right ventricular (RV) pressures in relation to the systemic pressures, RV and left ventricular (LV) functions and the adequacy of pulmonary arborisation. Method: Data of all surviving patients who underwent complete repair at Southampton University Hospital were reviewed. Data were obtained using case notes and computer based patient records. No data were gathered by direct patient contacts. LV and RV ejection fractions were measured by cardiac magnetic resonance imaging. Pulmonary arborisation patterns were assessed using cardiac catheter data. Results: A total of 26 patients had undergone complete repair. There were 8 (30.8%) deaths and the 18 survivors constituted the study group. Eleven (61.1%) had undergone three or more surgeries to attain complete repair. Fifteen (83.3%) maintained resting saturations above 80% after surgery. Nine (50%) had undergone three or more catheter interventions after complete repair. Eleven (61.1%) had undergone one or more pulmonary ballooning. Nine (50%) had undergone pulmonary artery (PA) stenting. Four (22.2%) had a RV ejection fraction (EF) 50% of LV pressures. Certain zones of the lungs were significantly under-filled on complete repair. Conclusions : Children with pulmonary atresia, ventricular septal defect and major aorto-pulmonary collaterals can be treated using a staged repair. There is a high mortality (31%) with average functional results. Sri Lanka Journal of Child Health , 2014; 43 (2): 84-87 (Key words: Pulmonary atresia; ventricular septal defect; major aorto-pulmonary collaterals) DOI: http://dx.doi.org/10.4038/sljch.v43i2.7008

Experimental study of bioabsorbable iron-based pulmonary artery stent

Objective To monitor the degradation and bio-safety features of the bioabsorbable iron-based stent planted in the pig pulmonary artery. Methods A total of 19 miniature pigs were randomly assigned into 3 groups.Three cases were assigned as the control group; ten cases were assigned as stent implantation group A with one stent implanted in the pig pulmonary artery; the other six cases were assigned as stent implantation group B with two stents implanted in the pig pulmonary artery.Follow-up studies for 24 months were conducted in all cases.Repeated measures ANOVA were used to collect and analyze statistical processing data at multiple time points of the follow-up. Results After surgery, pulmonary artery blood flow velocity and right ventricular pressure were measured by echocardiography and cardiac catheterization.There was no significant difference in pulmonary artery blood flow velocity(Fgroup×time=1.06, P=0.40) and right ventricular pressure (Fgroup×time=0.58, P=0.86) among each group, and no vascular re-narrow circumstance was indicated.Pulmonary artery diameter expansion rate between stent group and control group was statistically different (Fgroup=3.57, P=0.05; Ftime=12.89, P<0.001; Fgroup×time=2.99, P=0.03), suggesting that the stent could maintain a good expansion of the role of vascular in the follow-up period even though in degradation.Difference in the level of serum iron concentrations among the groups was not statistically significant (Fgroup×time=0.94, P=0.52), suggesting that there was no evidence of iron overload.All animals survived to the follow-up endpoint, and no serious side effects caused by stent implantation were found. Conclusions Bioabsorbable iron-based stent planted in the pig pulmonary artery may experience a certain degree of degradation, and it is safe and stabile in animals. Key words: Bioabsorbable stent; Iron; Pulmonary artery; Congenital heart disease; Child

Pulmonary artery stent for bronchial adenoid cystic carcinoma causing pulmonary artery stenosis.

A 46-year-old woman presented with a 6-month history of dyspnea and weight loss on a background of previous pneumonectomy for bronchial adenoid cystic carcinoma 14 years beforehand. Several years prior to this presentation, she had developed left vocal cord palsy and a metastatic lesion to the right buttock confirmed at resection. Investigations included CT pulmonary angiography and right heart catheterisation and demonstrated pulmonary artery stenosis suggestive of vascular encasement, severe pulmonary arterial hypertension and pulmonary nodules. Subsequent pulmonary artery stenting markedly improved both pulmonary artery pressures and the patient's symptoms. The diagnosis of pulmonary artery stenosis due to mediastinal infiltration by metastatic bronchial adenoid cystic carcinoma was based on these findings as well as the presence of the pulmonary nodules and the previous mediastinal (recurrent laryngeal nerve) and metastatic complications. This case is the first report of successful pulmonary artery stenting for this rare complication.

Hybrid intraoperative pulmonary artery stenting in redo congenital cardiac surgeries

ObjectiveReconstruction of branch pulmonary arteries (PAs) can be challenging in redo congenital heart surgeries. Treatment options like percutaneous stent implantation and surgical patch angioplasty may yield suboptimal results. We present our experience with hybrid intraoperative stenting which may be an effective alternative option.MethodsWe retrospectively analyzed data of all patients with PA stenosis who underwent intraoperative PA branch stenting in our institution between January 2011 and December 2012.ResultsTen patients [6 females, median age 10 (1.4 to 37) years], underwent hybrid stenting of the PA. Primary cardiac diagnoses were pulmonary atresia with ventricular septal defect (VSD) in three patients, pulmonary atresia with intact ventricular septum in two, Tetralogy of Fallot (TOF) in one, Double outlet right ventricle (DORV) with pulmonary stenosis (PS) in one, complex single ventricle in two and VSD with bilateral branch PA stenosis in one patient. Concomitant surgeries were revision/reconstruction of RV-PA conduit in 4, Fontan completion in 4, repair of TOF with conduit placement in 1 and VSD closure in 1 patient. The left PA was stented in 7, the right in 2 and both in 1, with a total of 11 stents. There were no complications related to stent implantation. Two early postoperative deaths were unrelated to stent implantation. At mean follow-up period of 14.8 (12–26) months, stent position and patency were satisfactory in all survivors. None of them needed repeat dilatation or surgical reintervention.ConclusionHybrid stenting of branch PA is a safe and effective option for PA reconstruction in redo cardiac surgeries. With meticulous planning, it can be safely performed without fluoroscopy.

Plastic bronchitis: symptomatic improvement after pulmonary arterial stenting in four patients with Fontan circulation

Plastic bronchitis is a severe complication after a Fontan procedure, with an estimated incidence around 1-2% and poor prognosis. We present the cases of four patients with plastic bronchitis after a total cavopulmonary connection with a stenosis of the left pulmonary artery that was stented successfully. In three of the four patients, symptoms improved after catheter intervention in combination with pulmonary vasodilator and inhalative treatment.

Frequency and Risk of In-Stent Stenosis Following Pulmonary Artery Stenting

Peripheral and central pulmonary artery (PA) stenoses can result in right ventricular hypertension, dysfunction, and death. Percutaneous PA angioplasty and stent placement relieve obstruction acutely, but patients frequently require reintervention. Within a heterogeneous patient population with PA stents referred for catheterization because of noninvasive signs of PA obstruction, we have observed that in-stent stenosis (ISS) occurs commonly in some groups, challenging previous reports that this phenomenon occurs infrequently. We set out to evaluate the incidence and demographics of patients with previous PA stent placement who develop ISS. Consecutive patients with previously placed stents presenting for catheterization and undergoing PA angiography were reviewed (104 patients, 124 cases). We defined ISS angiographically, as a 25% narrowing of the contrast-filled lumen relative to the fluoroscopically apparent stent diameter at any site along the length of the stent. For inclusion, we required that the stenotic segment be narrower or equal in size to the distal vessel. ISS was diagnosed in 24% of patients, with the highest incidence among patients with tetralogy of Fallot and multiple aortopulmonary collaterals, Williams syndrome, or Alagille syndrome. In conclusion, ISS after PA stent placement is a more frequent problem than previously reported, and patients with inherently abnormal PAs are disproportionately affected. Increased clinical surveillance after stent placement and investigation of innovative preventive strategies may be indicated.

Single-Center Outcome Analysis Comparing Reintervention Rates of Surgical Arterioplasty With Stenting for Branch Pulmonary Artery Stenosis in a Pediatric Population

Although catheter-based intervention is generally accepted as the treatment of choice for branch pulmonary artery (PA) stenosis, there are no data directly comparing both the need for reintervention and time to reintervention in patients undergoing transcatheter stenting versus surgical arterioplasty. We compared children who underwent surgical branch pulmonary arterioplasty and branch PA stent placement between January 2008 and May 2012 at a single tertiary center. Need for reintervention and mean time to reintervention were assessed using chi-square and independent sample Student t test. Thirty-seven patients were included (surgery n = 18, stent n = 19). Mean weight at initial intervention was 11.3 ± 8.8 kg for surgical and 20.1 ± 15.5 kg for stent (p = 0.041). Intervention was performed on the left PA in 17 patients, the right PA in 12 patients, and both PAs in 8 patients. Five patients had undergone previous intervention. On mean follow-up of 807 ± 415 days, 50% (9 of 18) of the surgery cohort and 5.3% (1 of 19) of the stent cohort required reintervention (p = 0.002). In all but one case reintervention was catheter-based. Mean time to reintervention for the surgery cohort was 272 ± 162 days and for the single stent cohort it was 150 days. When comparable age and weight groups were analyzed, reintervention was still more common in the surgery cohort (p = 0.007). Children undergoing surgical branch pulmonary arterioplasty are more likely to require reintervention than those undergoing stent placement.

CT angiography in Fontans with implanted stents

BackgroundCT angiography is used as a non-invasive method in the evaluation of patients with Fontan circulation. For good visualization of patients having undergone the Fontan operation the optimal scan timing and adequate intravenous route is important. PurposeThe aim of this study was to confirm that computer tomography is very a good tool for assessment of patients after Fontan procedure with implanted stents in pulmonary arteries or in fenestration. Material and methodsSix patients with Fontan circulation and implanted stent in left pulmonary artery or in fenestration underwent CT angiography. The CT angiography was successfully performed to all patients. For homogenous enhancement of Fontan pulmonary arteries and Fontan tract we decided to use 1-minute delay scan with right antecubital application of contrast agent. The optimal enhancement was evaluated at the right pulmonary artery (RPA), left pulmonary artery (LPA), and Fontan tract. Optimal enhancement was defined when evaluation of stent was possible. ResultsOptimal enhancement when the stent was possible to evaluate intraluminally was achieved in seven CT examinations. The Bland–Altman test demonstrated good agreement between readers. ConclusionsThis study demonstrates that CT angiography is a fast, accurate and reproducible method in the evaluation of patients with Fontan circulation, and implanted stent in pulmonary arteries or in fenestration.

Double-Outlet Right Ventricle With an Intact Ventricular Septum: A Unique Stage 1 Palliation

This report describes a case of double-outlet right ventricle with intact ventricular septum diagnosed in a newborn male. The initial diagnosis was made by echocardiography. The baby underwent a hybrid procedure including pulmonary artery banding and stenting of the patent ductus arteriosus. He subsequently underwent stenting of the atrial communication. The patient was discharged at 55 days of life with the intent to perform palliative repair at a later date.

Factors Impacting Echocardiographic Imaging after the Fontan Procedure: A Report from the Pediatric Heart Network Fontan Cross‐Sectional Study

Echocardiographic image quality in Fontan survivors may be limited by a variety of factors. We sought to describe echocardiographic quality and factors associated with study quality in subjects participating in the Pediatric Heart Network Fontan Cross-Sectional Study. Echocardiograms were obtained at 7 clinical sites using a standard protocol. Quality grading and analysis were performed by a core laboratory. Univariate and multivariable modeling were performed to assess factors associated with quality and ability to obtain images sufficient for prespecified quantitative analysis. A total of 543 echocardiograms were obtained. The quality of echocardiograms improved over the duration of the study. The great arteries, systemic veins, and pulmonary veins were less likely to be adequately imaged than other cardiac structures. Quantitative analysis of ventricular volume was possible in 76% overall, but only 41% of those with mixed ventricular morphology. Factors independently associated with better quality included younger age, levocardia, acquisition of the echocardiogram at a longer time since the beginning of enrollment, absence of a pulmonary artery stent, and clinical site. Patient and center-specific factors are associated with echocardiographic quality after the Fontan procedure. Increased familiarity and experience with a standard imaging protocol is likely to result in improved quality.

Balloon Angioplasty and Stent Implantation Performed Through Systemic-to-Pulmonary Artery Shunts in Infants and Neonates

Branch pulmonary artery stenosis (BPAS) in the setting of systemic-pulmonary artery shunts (SPS) may result in significant sequelae. Limited information exists regarding the safety and efficacy of pulmonary artery balloon angioplasty and stent implantation via SPS in neonates and infants. This study aimed to examine the feasibility, safety, and efficacy of balloon angioplasty/stent implantation for BPAS performed via SPS in neonates and infants. A single-center retrospective analysis of all patients weighing 10 kg or less who underwent angioplasty for BPAS via SPS was performed. Systemic oxygen saturations and vessel diameter before, during, and after the procedure were compared. Between July 1996 and February 2008, 15 patients underwent 20 catheterizations for the treatment of 27 BPAS via SPS. The patients had a mean weight of 5.6 kg (range, 2.6-10 kg) and a mean age of 7.6 months (range, 7 days to 33 months). The SPS diameter ranged between 2 and 5 mm (median, 3.5 mm). Angioplasty was performed for all 27 lesions, and an additional stent was placed in 5 of these. The average lesion diameter increased from 2.3 ± 1.5 to 4.7 ± 1.7 mm (p < 0.05), and 25 (93 %) of the 27 lesions met the predetermined criteria for success. Systemic oxygen saturation increased from 73 ± 9.5 % to 82 ± 6.8 % immediately after intervention and was 83 ± 7.9 % at discharge (p < 0.05). There were no instances of shunt thrombosis. Two patients experienced transient hypotension during the procedure. No procedural deaths occurred. The study findings suggest that balloon angioplasty or stent implantation performed via SPS appears to be safe and effective treatment for BPAS in neonates and infants.

Impact of stent implantation on pulmonary artery growth

Goals of stent implantation (SI) in children with pulmonary artery (PA) stenosis are to relieve obstruction and improve flow to the distal vasculature. We evaluated stent impact on distal PA growth. We compared data of children who underwent unilateral SI using the nonstenotic contralateral PA (CPA) as a control (1998-2005; f/u data through 2009). Main/lobar diameters measured at initial and f/u catheterizations were analyzed. For single ventricle (SV) patients (N = 18), the stented PA diameter (SPA D) increased 118%. At initial f/u catheterization (14 ± 9.6 months), both upper lobe (UL) and lower lobe (LL) growth of SPA was comparable to those of the CPA (UL:7% vs. 7%; P = 0.97); (LL:5% vs. 10%; P = 0.33). Subsequent f/u in 11/18 patients (mean 26 ± 20 months) revealed similar results: both UL and LL growth of SPA were comparable to those of the CPA (UL:51% vs. 27%; P = 0.3); (LL:18% vs. 21%; P = 0.62). For two-ventricle (2V) patients (N = 21), the SPAD increased 100%. At f/u, UL, and LL growth on SPA was similar to those of the CPA (UL: 32% vs. 21%; P = 0.37); (LL: 17% vs. 18%; P = 0.88). Subsequent f/u in 10/21 patients (mean 34 ± 14 months) showed UL growth of SPA was significantly greater than that of the CPA (44% vs. 21%; P = 0.05). LL growth of SPA was similar to that of the CPA (19% vs. 14%; P = 0.56). SI for PA stenosis is effective in promoting normal lobar growth in SV and 2V patients. Greater lobar growth was seen in 2V compared to SV pts at first f/u. Early, aggressive PA stenting is beneficial in promoting lobar branch growth.

“Downhill” Esophageal Varices in Congenital Heart Disease

“Downhill” Esophageal Varices in Congenital Heart Disease

Circulation: Cardiovascular Interventions Editors’ Picks

<i>Circulation: Cardiovascular Interventions</i> Editors’ Picks

Abstract 19051: Accuracy and Internal Consistency of Cardiac Magnetic Resonance Imaging in Measuring Branch Pulmonary Arterial Flows in Conotruncal Anomalies Patients with Branch Pulmonary Arterial Stents

Introduction Conotruncal Anomalies patients may require branch pulmonary arterial (BPA) stent implantation. These ferromagnetic stents generate localized artifact that may affect phase contrast magnetic resonance (PCMR) imaging. There is little data on PCMR measurements in the presence of a BPA stent. Hypothesis PCMR acquired measurements away from the BPA stent artifact are accurate and internally consistent. Methods We retrospectively reviewed 43 consecutive repaired Conotruncal Anomalies PCMR and cine MR studies between 2005 and 2012. All patients underwent either left (30) pulmonary artery (LPA) or right (20) pulmonary artery (RPA) stent placement. Three different methods of measuring flow through the stented artery were compared: 1) main pulmonary artery (MPA) - unstented artery, 2) direct PCMR of the stented artery away from the artifact, and 3) pulmonary venous (PV) flows (see Figure). Where available, pulmonary radionuclide scintigraphy (PRS) was compared to each method. Significance was P &lt; 0.05. Results For the entire study population, the mean age and body surface area were 12.0 ± 7.0 yrs (range 1.5 - 33.2 yrs) and 1.2 ± 0.5 m2. There was good agreement without significant difference between the mean PRS and MPA derived stented artery flow (method 1) (37 ± 17 and 35 ± 21 %, r=0.731, ICC=0.8403, p=0.627) There was even better agreement between PRS and direct measurement (method 2) (39 ± 20 and 40 ± 22%, r=0.888, ICC = 0.943, p=0.757). The greatest agreement was found between method 2 and PV flows (method 3) (48 ± 17 and 47 ± 14%, , r=0.939, ICC=0.961, p=0.837). As another check for internal consistency, there was excellent correlation between the PCMR and cine MR right ventricular stroke volume 70.2 ± 40.4 and 74.0 ± 41.4 cc, r=0.983, ICC=0.989. Conclusion In the presence of a ferromagnetic BPA stent, accurate measurement of the net fractional flow ratio is feasible. PCMR adjacent to the stent artifact or pulmonary venous flows provide the most internally consistent data.

Catheter intervention for branch and crossed pulmonary arteries

Introduction Over the last decade, stent implantation has become a widely accepted, effective therapy for the treatment of pulmonary arterial (PA) stenoses. Stent implantation has proved to be a safe procedure with minimal complications. Objectives To review our experience with branch PA stenting. We reviewed also catheter based interventions for patients with right aortic arch and crossed pulmonary arteries associated with branch PA stenosis. Method Retrospective data analysis of all patients who had branch PA stenting at KACC, NGHA, Riyadh KSA, during the period from January 2006 till October 2009. Patients with pulmonary atresia VSD and MAPCAS were excluded. Results Twenty-one patients were identified to have PA stenting during the study period. 14 were females (66.7%). Six patients (29%) were syndromic (Alagile syndrome, DiGeorge syndrome, Down syndrome, Goldenhar Syndrome, and Noonan Syndrome). Five patients (24%) had crossed Pas. Seven patients (33%) had PA, VSD, PDA, Two had TOF, one had AVSD with TOF, one DORV, one TGA, one truncus arteriosus with IAA type B, and one had Bicuspid AV with aortic stenosis as a primary diagnosis. All of them had branch PA stenting as a secondary procedure (post surgical intervention). Six patients (29%) had PA stenting as a primary intervention with no prior surgical intervention. Six patients (29%) had Bilateral branch PAs stenting, 11 (52%) had LPA stenting and 4 (19%) had RPA stenting. The median age at branch PA stenting was 35 months (range 2 months to 45 years). The median weight was 10.5 kg (2.8–100 kg). The median F/U period was 32 months (40 days to 61 months). Ten patients (48%) required stent dilatation after a median period of 28 months (12–38 months). One patient had failed LPA stenting (stent embolized and parked into RPA) who later underwent another intervention with successful LPA stenting. Conclusion Stent implantation has proved to be a safe procedure with minimal complications. Even in those with crossed Pas. Restenoses is long term concerns which are amenable to redilatation with excellent results.

Endovascular Management of Pulmonary Artery Stenosis due to Tumor Compression

A 75-year-old man with invasive thymoma encasing the aortic arch and pulmonary arteries was referred to our institution with a 1-year history of dyspnea and worsening right heart failure. Pulmonary angiogram demonstrated greater than 90% stenosis of the right pulmonary artery. Balloon angioplasty and stent placement were performed with immediate improvement in his shortness of breath and peripheral edema. Improved lung opacification was noted on completion arteriography, and the stents remained patent until the patient expired from complications related to his cancer 2 years later. Pulmonary artery stenting in noncongenital causes of stenosis is a safe and effective therapy.

Medium and Long-Term Outcomes After Bilateral Pulmonary Artery Stenting in Children and Adults With Congenital Heart Disease

Percutaneous stenting of branch pulmonary arteries (PAs) has become an important interventional therapy in the complete management of congenital heart disease. Few data exist on long-term outcomes for patients requiring placement of bilateral stents. This study aimed to determine the medium- to long-term outcomes after bilateral stenting of branch PAs in patients with congenital heart disease. A retrospective study analyzed all procedural and follow-up data on patients undergoing bilateral PA stenting during a single procedure. From October 2001 to May 2012, 26 patients underwent bilateral PA stenting (total of 62 stents). The mean age of these patients was 9.5 ± 12 years, and their mean weight was 27 ± 19 kg. The mean procedural time was 191 ± 67 min, and the mean fluoroscopy time was 50 ± 29 min. The mean gradient across the right pulmonary artery decreased from 35 ± 22 to 11 ± 12 mmHg (p < 0.001). The left pulmonary artery gradient decreased from 32 ± 17 to 10 ± 12 mmHg (p < 0.001), and the right ventricle to descending aorta pressure ratio decreased from 71 ± 18 % to 46 ± 13 % (p < 0.001). Intraprocedural adverse events were encountered in four patients (1 small PA dissection, 2 intraprocedural arrhythmias, and 1 first-degree burn on the thigh). The mean follow-up period was 41 ± 23 months. Two deaths occurred. Further interventions were required for 12 patients. Bilateral PA stenting is effective and safe, with an instantaneous significant decrease in pressure gradients. The need for reintervention is common, so continued follow-up assessment is warranted.