Branch Pulmonary Artery Stenosis Research Articles

Premounted stents for branch pulmonary artery stenosis in children: A short term solution

Define outcomes of premounted stent implantation (PMS) for branch pulmonary artery stenosis (BPAS). PMS for BPAS in children raises concern of long term viability, with limited maximal expansion. We reviewed our cardiac database over an 11-year period ending in 2013. Primary endpoint was need for surgical stent intervention (SSI). Other endpoints included acute results and repeat interventions (RI). 82 PMS were implanted in 60 children for BPAS. Median weight was 6.3 (25th -75th 4.6-9.8) kg. Median stent diameter was 6 (range 4-9) mm. Acutely, vessel diameter improved from 2.0 (25th -75th 1.6-3.4) to 5.0 (25th -75th 4.2-5.9) mm (p < 0.001), pressure gradient decreased from 41 (25th -75th 29-50) to 11 (25th -75th 7-18) mmHg (n = 47, p < 0.001), RV:Ao pressure ratio decreased from 100% (25th -75th 85-110%) to 59% (25th -75th 49-74%) (n = 40, p < 0.001). Freedom from SSI was 81% at 1 year and 35% at 5 years. Freedom from RI was 50% at 1 year and 14% at 5 years. 86% of PMS underwent SSI during a concomitant planned cardiac surgery. 45% patients had stent redilation, improving stent diameter from 4.6 (25th -75th 4.1-5.4) to 5.7 (25th -75th 4.9-7) mm (p < 0.001). 1 stent (3%) was able to be fractured longitudinally. PMS is an effective short term solution for BPAS in children. PMS is associated with expected early need for transcatheter reintervention to accommodate for growth, but also has high rates of SSI.

TCT-60 Stent Treatment of Branch Pulmonary Artery Stenosis in Children With Congenital Heart Disease After Cardiac Surgery

Residual or recurrent branch pulmonary artery stenosis is a common finding after cardiac surgery for congenital heart disease. We report our experience using stents to treat branch pulmonary artery stenosis in children with congenital heart disease following surgical correction of stenotic or

D-Transposition of the Great Arteries: A New Era in Cardiology

Before the 1950s, D-transposition of the great arteries was associated with nearly 90% mortality within the first year of life. The Mustard and Senning procedures resulted in a significant increase in the lifespan of these patients but with notable long-term complications, including arrhythmias, sinus node dysfunction, chronotropic incompetence, and right ventricular systolic dysfunction. The arterial switch operation (first described by Adib Jatene) initially resulted in nearly universal death. However, the use of coronary buttons for coronary artery translocation has improved operative survival dramatically. It is now considered the treatment of choice in patients amendable to the arterial switch operation. Considered an anatomic repair, resulting in concordant ventriculoarterial connections and a systemic left ventricle, the arterial switch operation reduces the incidence of ventricular dysfunction. However, it is also associated with long-term complications, including aortic root dilatation, aortic valve regurgitation, right ventricular outflow tract obstructions, coronary artery stenosis/compression, and branch pulmonary artery stenosis.

Consequences of an early catheter-based intervention on pulmonary artery growth and right ventricular myocardial function in a pig model of pulmonary artery stenosis.

To determine the consequences of an early catheter-based intervention on pulmonary artery (PA) growth and right ventricular (RV) myocardial function in an animal model of branch PA stenosis. Acute results and safety profiles of deliberate stent fracture within the pulmonary vasculature have been demonstrated. The long-term impact of early stent intervention and deliberate stent fracture on PA growth and myocardial function is not understood. Implantation of small diameter stents was performed in a pig model of left PA stenosis at 6 weeks (10 kg) followed by dilations at 10 (35 kg) and 18 weeks (65 kg) with intent to fracture and implant large diameter stents. Hemodynamics, RV contractility, and 2D/3D angiography were performed with each intervention. The heart and pulmonary vasculature were histologically assessed. Stent fracture occurred in 9/12 and implantation of large diameter stents was successful in 10/12 animals with no PA aneurysms or dissections. The final stented PA segment and distal left PA branch origins equaled the corresponding PA diameters of sham controls. Growth of left PA immediately beyond the stent was limited and there was diffuse fibro-intimal proliferation within the distal left and right PA. RV contractility was diminished in the intervention group and the response to dobutamine occurred uniquely via increases in heart rate. Early stent intervention in this surgically created PA stenosis model was associated with improved growth of the distal PA vasculature but additional investigation of PA vessel physiology and impact on the developing heart are needed.

Routine Cardiac Catheterization Prior to Fontan Operation: Is It a Necessity?

Prior to the Fontan procedure, patients with single ventricle physiology with Glenn shunt are typically referred for cardiac catheterization to assess hemodynamics and potentially provide interventional measures. Currently, echocardiography provides detailed information which together with other non-invasive imaging such as CT scan and MRI may obviate the need for routine cardiac catheterization prior to the Fontan procedure. In this study, we examine the findings in cardiac catheterization in this population to determine: (a) the accuracy of echocardiography in providing adequate information prior to the Fontan procedure, particularly in identifying those in need of per-catheter intervention, and (b) the percentage of patients requiring interventional procedures during cardiac catheterization. We performed a retrospective chart review of echocardiographic and cardiac catheterization data for patients who underwent pre-Fontan cardiac catheterization at our center in the period from 02/01/2008 to 02/28/2017. We aimed to re-examine the necessity of routine cardiac catheterization in all single ventricle patients. This was performed through examining pre-catheterization echocardiography reports and comparing them to findings of the subsequent cardiac catheterization reports. Echocardiography reports were evaluated for accuracy in identifying significant anatomical or hemodynamic findings, which may impact success of Fontan procedure as well as the ability of echocardiography to predict findings important to know prior to the Fontan procedure. In this cohort of 40 children, 3 patients were found to have significant hemodynamic findings through cardiac catheterization which were not previously known by echocardiography. In addition, 28 out of 40 patients (70%) required interventional procedures to address significant abnormalities (systemic to pulmonary arterial collaterals, pulmonary artery stenosis, aortic arch stenosis, etc.). All cases of aortic arch stenosis were detected by echocardiography, however, all patients who required systemic to pulmonary arterial or left SVC embolization were not detected by echocardiography. Furthermore, echocardiography did not detect the need for branch pulmonary artery stenosis in 50% of cases. Cardiac catheterization appears to be an essential part of patient assessment prior to Fontan completion in patients with single ventricle physiology. This current practice may change in the future if a non-invasive screening tool is found to have high positive and negative predictive values in identifying the subset of patients who require potential intervention in pre-Fontan cardiac catheterization.

Modified Repair of Type I and II Truncus Arteriosus Limits Early Right Ventricular Outflow Tract Reoperation

Repair of truncus arteriosus often requires early right ventricular outflow tract (RVOT) reoperation. Using a modified repair, the branch pulmonary arteries are left in situ, which may avoid earlier RVOT reoperation. We hypothesized that our modified repair for type I and II truncus arteriosus would extend the time to RVOT reoperation. Infants with truncus arteriosus were divided into 2 groups: (1) traditional technique where the branch pulmonary arteries are excised from the truncal root, or (2) modified repair where the branch pulmonary arteries are left in situ and septated from the truncal root. Regardless of the approach, a bioprosthetic conduit or homograft was used to establish right ventricular to pulmonary artery continuity. Follow-up pulmonary artery angiograms were used to assess for branch pulmonary artery stenosis. From 54 infants (modified repair: 33, traditional technique: 21), there were no significant differences in age at repair, gender, or type of truncus arteriosus. With 100% follow-up, use of the modified repair resulted in a lower rate of branch pulmonary artery stenosis, and greater freedom from surgical branch pulmonary arterioplasty. Five- and 10-year freedom from RVOT reoperation (5 years: modified-81.5% vs traditional-30.5%, P = 0.004; 10 years: modified-53.3% vs traditional-30.5%, P = 0.01) favored the modified repair. Cox regression analysis demonstrated that the modified repair was associated with an independently lower risk for RVOT reoperation (hazard ratio: 0.08, confidence interval: 0.01, 0.75, P = 0.02). Thus, maintaining the branch pulmonary artery architecture resulted in greater freedom from RVOT reoperation.

Hybrid Approach for Branch Pulmonary Artery Stenosis in Congenital Heart Disease

Hybrid Approach for Branch Pulmonary Artery Stenosis in Congenital Heart Disease

Recanalization of the left pulmonary artery with radio-frequency perforation and stent angioplasty after failed intraoperative stent implant.

Patients with pulmonary atresia with a ventricular septal defect are often palliated with a right ventricle to pulmonary artery conduit. Pulmonary artery interventions can result in the development of stenosis, and less commonly, atresia. We describe a novel case where an 11-month-old infant male with pulmonary atresia, ventricular septal defect, and bilateral branch pulmonary artery stenosis developed discontinuity of the left pulmonary artery, and was successfully recanalized with radiofrequency perforation and stent angioplasty, after a failed attempt at an intraoperative stent implantation.

Stenting the complex patent ductus arteriosus in tetralogy of Fallot with pulmonary atresia: challenges and outcomes.

Patent ductus arteriosus (PDA) stenting has gained acceptance for palliation in cyanotic congenital heart disease. The PDA in tetralogy of Fallot with pulmonary atresia (ToF-PA) arises, in the left aortic arch, from underneath the arch and connects to the proximal left pulmonary artery, often resulting in stenosis. The PDA is usually elongated and tortuous, making stent implantation challenging. Shorter duration of palliation, aggravation of branch pulmonary artery stenosis resulting in poor growth and difficulty at surgery makes ductal stenting controversial. Access via the carotid and axillary artery reduces complexity of the procedure and improves success, with recent data demonstrating good pulmonary artery growth. Advances in bioresorbable stents offer future promise and will likely resolve some controversies surrounding PDA stenting in ToF-PA.

Long-Term Outcomes After Surgical Pulmonary Arterioplasty and Risk Factors for Reintervention

Although surgical patch arterioplasty is the conventional therapy for branch pulmonary artery (PA) stenosis, limited data exist on long-term outcomes. We examined the incidence of and risk factors for reintervention after surgical arterioplasty for branch PA stenosis in biventricular congenital heart disease. This retrospective cohort study included patients with 2-ventricle physiology who underwent patch arterioplasty for PA stenosis at a single high-volume congenital heart center during a 10-year period. Freedom from surgical or percutaneous reintervention for recurrent PA stenosis was evaluated. Univariate and multivariable Cox regression analyses were performed to determine risk factors for reintervention. Among 135 patients, the median age at patch arterioplasty was 0.9 years. Survival to hospital discharge (or 30 days postoperatively) was 96%. During a median follow-up period of 4.0 years, reintervention for PA stenosis occurred in 38 of 115 patients (33%) at a median time to reintervention of 1.4 years. The overall 10-year reintervention rate was 54%. In univariate analysis, age less than 30 days at initial arterioplasty, congenital PA stenosis (vs acquired), and bilateral PA stenosis (vs unilateral) were significantly associated with reintervention. In multivariable analysis, neonatal age (adjusted hazard ratio, 3.6; p= 0.002) and bilateral PA stenosis (adjusted hazard ratio, 2.8; p= 0.005) remained independently associated with reintervention. Long-term reintervention for recurrent PA stenosis after patch arterioplasty is common. Patients with bilateral PA stenosis or age younger than 30 days at the time of the index pulmonary arterioplasty are at higher risk for reintervention. These patients may benefit from frequent monitoring or novel approaches to repair.

Intraoperative Stenting of Pulmonary Artery Stenosis in Children With Congenital Heart Disease

Branch pulmonary artery (BPA) stenosis is frequently associated with congenital heart disease. Management of BPA stenosis is challenging for surgeons due to a high rate of recurrence. The purpose of this study was to assess the results of intraoperative pulmonary artery stenting associated with or without surgical angioplasty. We included 33 children from our center between January 2008 and July 2014. Patients had pulmonary atresia with ventricular septal defect (13), tetralogy of Fallot (10), troncus arteriosus (4), double outlet right ventricle (2), and single left or right ventricle (4). A total of 44 balloon-expandable stents (mean diameter, 9.5 mm; range, 4 to 16 mm) were deployed in left or right PA under direct visualization, without the use of fluoroscopy, after branch angioplasty for 28 of them (64%). The mean age at surgery was 4.3 ± 4.3 years (range, 6 days to 15 years) and the mean weight was 14.3 ± 11.9 kg (range, 2.8 to 63 kg). Postoperative mortality was 9% (3 patients), but only 1 death was related to the stenting procedure. Twenty-five patients underwent angiographic control after a mean follow-up of 22 months after surgery. All stents were well positioned. The mean stented BPA Z-score increased from -2.6 ± 1.8 to -0.4 ± 1.6 (p < 0.0001). Eleven patients experienced intrastent proliferation (44%). Among them, 2 patients required a reoperation for severe intrastent stenosis, whereas the 9 others had mild intrastent neointimal proliferation, which was successfully managed by balloon expansion. Intraoperative stenting of BPA is a safe and effective option to treat BPA stenosis and prevent recurrence.

Lecture 7: Management of Critical CHD Neonates: Focus on PDA Stenting

Duct-dependent pulmonary circulation is one of the most common form of critical congenital heart disease in neonates. Cyanosis is the predominant presentation symptom. Infusion of Prostaglandin E1 is helpful in maintaining short-term ductal patency. An urgent systemic-to-pulmonary artery shunt is required to maintain the blood flow supply to pulmonary arteries. But the complications related to placing a shunt to pulmonary arteries were not infrequent in neonates. With the advent of transcatheter techniques, stenting of patent ductus arteriosus (PDA) can be an alternative to systemic-to-pulmonary artery shunts. Recently, bare coronary stents have been successfully used to stent PDA. The vascular access to stent PDA can be either from a prograde route (femoral vein) or retrograde route (axillary artery). Sometimes, more than one stent is required to covert the whole length of ductus. Generally, a 3.5 mm or 4.0 mm coronary stent was used. Neonates with a non-restrictive large ductus (narrowest diameter ≥ 2.5 mm) or juxta-ductal branch pulmonary artery stenosis should be excluded. Anti-platelet agents should be given to prevent thrombosis within the stent. Although stenting PDA is a safe procedure and can be an alternative to shunt placement, complications such as stent migration, thrombus and heart failure were not uncommon.

Stenting of the ductus arteriosus in infants with functionally univentricular heart disease and ductal-dependent pulmonary blood flow: A single-center experience.

To determine the short- and medium-term outcomes of ductal stenting (DS) in patients with functionally univentricular hearts (FUHs) and ductal-dependent pulmonary blood flow. Several studies have evaluated the outcomes of DS in a limited number of patients with FUHs. Nonetheless, there is still no consensus regarding the indications for this procedure, and no appropriate patient selection criteria have been devised. From 2005 to 2015, cardiac catheterization for DS was performed in 68 patients with FUHs. Of these patients, 49 had single source pulmonary blood flow from ductus arteriosus. Procedural and follow-up data were evaluated. The median weight of the patients was 3.6 kg (2.3-6.8 kg), and the median age was 26 days (3 days-8 months). The technical success rate of the procedure was 95% (65 of 68 patients). Mean oxygen saturation increased from 70% ± 7.6% to 87% ± 4.6% (P < 0.0001). Among patients in whom DS was successful, 55 (84.6%) were bridged to a Glenn procedure after a median of 9.1 months (6.4-14 months), and 41 (63%) were successfully bridged to a Glenn procedure without additional interventions. Of the 16 patients with preexisting mild pulmonary artery stenosis, five required a surgical shunt due to progressive branch pulmonary artery stenosis, while nine were bridged to a Glenn operation without shunt placement. Five (7.3%) patients died, including patients who were sent to surgery. DS is a reasonable and effective alternative to surgical shunt placement as a first-stage palliative procedure in patients with FUHs. © 2016 Wiley Periodicals, Inc.

Pulmonary Artery Branch Stent Implantation in Congenital Heart Disease: A 10-Year Multicenter Experience

Background: Stent implant is considered the treatment of choice for most cases of congenital or postoperative pulmonary artery branch stenosis in patients with congenital heart defects. However, there are still doubts on the clinical effectiveness and the incidence of complications of this technique that need to be elucidated.Methods: This multicenter study has a descriptive, observational and retrospective design. The procedures were performed between January 2005 and April 2015. Twenty-five patients with pulmonary artery branch stenosis underwent stent implant and were followed-up both clinically and by different imaging tests. Persistent clinical and/or anatomic improvement defined clinical effectiveness.Results: Average age was 9.48 years (2 months-34 years), mean weight was 27.54 kg (3-104 kg) and 44% were women. The most frequent congenital heart defects in the treated cohort were tetralogy of Fallot and its variants, followed by single ventricle heart physiology after bidirectional Glenn shunt and/or Fontan-Kreutzer procedures. Right ventricular systolic and pulmonary artery pressure decreased significantly after the intervention (from 68.35 mmHg to 45.8 mmHg and from 47.4 mm Hg to 32 mm Hg, respectively) (p < 0.0001). The initial minimum diameter of the treated pulmonary artery branch increased significantly after the procedure (from 3.98 mm to 9.82 mm, p < 0.0001). The incidence of complications was 8% (n = 2) and the clinical effectiveness of the procedure was good in 22 patients (88%).Conclusions: Stent implant in pulmonary artery branch stenosis is a safe and feasible though challenging technique, with significant clinical and anatomic improvement. The procedure represents an alternative to surgery and decreases the need for reinterventions in patients with congenital heart defects.

Morphological and Hemodynamic Effectiveness of Stenting for Pulmonary Artery Stenosis - Subanalysis of JPIC Stent Survey.

Percutaneous stenting for branch pulmonary artery stenosis is an established interventional choice in congenital heart disease. The apparent morphologic change in the vessel diameter often differs from the hemodynamic result. We performed a subanalysis of the data from the Japanese Society of Pediatric Interventional Cardiology (JPIC) stent survey. The factors that may have contributed to morphologic effectiveness included reference vessel diameter (RVD), minimum lumen diameter (MLD) and percent diameter stenosis (%DS) and the relation between morphologic and hemodynamic effectiveness was evaluated in 206 lesions treated with stenting. We defined a "50% increase in MLD" as "morphologically effective", while "achievement of either a reduced pressure gradient greater than 50% or an increase of perfusion ratio to the affected side to the contralateral side greater than 20%" as "hemodynamically effective". Morphologic effectiveness was achieved in 84% of patients. Before stenting, %DS was significantly larger, while RVD was smaller in the "effective" group than in the "non-effective" group. The cutoff value for effective stenting was 51% for %DS and 14.7 mm for RVD before stenting. Hemodynamic effectiveness was obtained more often in the "morphologic effective" group. RVD and %DS were the 2 main contributors to acute morphologic effectiveness. There was a significant relationship between "morphologic effectiveness" and "hemodynamic effectiveness", judging from increased perfusion of the affected lung and/or decreased pressure gradient. (Circ J 2016; 80: 1852-1856).

Localization of Viral Antigens Improves Understanding of Congenital Rubella Syndrome Pathophysiology

Rubella virus (RV) is responsible for benign postnatal and deadly antenatal infections. Its involvement in developmental defects in children following congenital transmission was first made by Sir Norman McAlister Gregg in 1941. Indeed, the maternal primary infection results in an RV viremia and placental transfer. If it occurs before 12 weeks of gestation, during organogenesis, it can result in severe fetal damage causing miscarriage or malformations primarily affecting the cardiovascular system, eyes, ears and the central nervous system; it is fatal in nearly one third of cases during the first year of life (Tondury and Smith, 1966). This severe RV infection acquired in utero early in pregnancy is named as Congenital Rubella Syndrome or CRS. In 2014, 141 CRS cases were reported from 114 countries mostly from South-East Asia (n = 86/141), although reporting is probably inconsistent according to the authors themselves (Grant et al., 2015). This number had been estimated as closer to 100,000 cases each year in developing countries alone (Cutts and Vynnycky, 1999). To better understand the pathogenesis of CRS in the absence of an animal model, the first histopathological explorations were conducted in some of the 20,000 fetuses infected during the 1964–1965 epidemics in the US when about 12.5 M Rubella cases were reported (National Communicable Disease Center, 1969). Although these studies identified histological lesions in the heart, blood vessels, crystalline lens, ears, brain, teeth and liver consistent with clinical features and sequelae of CRS, they did not solved the mechanisms of virus teratogenicity (Tondury and Smith, 1966, Esterly and Oppenheimer, 1969). In particular, until recently, the exact nature of the cell types infected with RV remained unknown.

Abstract 16098: Mechanism of Branch Pulmonary Artery Stenosis After the Arterial Switch Operation

Background: Branch pulmonary artery (PA) stenosis, most commonly on the left, is a recognized postoperative complication of the arterial switch operation (ASO) for transposition of the great arteries. We hypothesized that greater rightward rotation of the neopulmonary root and dilation of the ascending aorta are associated with stenosis of the left PA (LPA). Methods: This study represents a retrospective analysis of cardiac magnetic resonance imaging (CMR) studies performed in patients after ASO. Neo-pulmonary root position in relation to the aorta was expressed as an angle, with a negative angle implying a rightward neo-pulmonary root. For the purpose of this study, perfusion imbalance was defined as &lt;40% of pulmonary blood flow to the affected lung. The offset between the LPA and right PA (RPA) as a result of cranial displacement of the LPA by asymmetric aortic root dilation was measured in the coronal plane. Results: 74 patients / studies were included for analysis. 73% had no branch PA stenosis, 24% had LPA stenosis and 3% had RPA stenosis. LPA area indexed to BSA was smaller than RPA area (287 ± 185mm2 vs 151 ± 114mm2, p=0.001). Smaller LPA area correlated with reduced LPA flow (r=0.213, p=0.0001) and a greater rightward positioning of the neopulmonary to aortic root (r=0.361, p=0.002). There was no correlation between LPA size or flow and offset of the LPA take-off due to an enlarged aortic root. Patients with reduced relative LPA flow were more likely to have required pulmonary arterioplasty with the primary repair (17% vs 2%, p=0.04), had a smaller LPA area [102±102mm2 vs 160±108mm2, p=0.04) and a smaller anterior-posterior thoracic diameter (101±53mm vs 131±55mm, p=0.04). There was no significant difference in patient demographics, cardiac diagnosis, age at operation, aortic root dimension, ventricular volumetrics or ventricular function between patients with normal LPA flow vs. reduced LPA flow. Patients with reduced LPA flow did not have greater peak gradients on echo. Conclusions: Greater rightward rotation of the neopulmonary root is associated with reduced LPA size and likely contributes to the development of LPA stenosis after ASO.

Abstract 18478: Balloon Angioplasty of Branch Pulmonary Arteries in Children: A Long Term Outlook

Introduction: Balloon angioplasty (BA) is widely employed for branch pulmonary artery stenosis (BPAS) in children. Vessel recoil, and hence need for repeat intervention, is common. Hypothesis: BA of BPAS has poor long term outcomes. Methods: We reviewed our cath database over an 11-year period ending in 2013 and collected data for all pts undergoing BA for BPAS. Primary endpoint was repeat intervention (RI), with other endpoints including acute results, and need for stent or surgical PA plasty (S/S). Central branch pulmonary artery (cPA) was defined as pre-hilum, while peripheral BPA (pPA) was define as post-hilum. Results: 175 pts underwent 371 BA procedures for BPAS. Primary diagnosis included major aorto-pulmonary collateral arteries (MAPCAs) in 18% (n=32) pts, and single ventricle in 11% (n=20) pts. Median age and weight were 23.6 (9.9 - 65.8) months and 10.7 kg (7.8 - 18.2 kg). Pt follow up was 4.1 (1.1 - 6.5) years. 69% (n=256) of BA was performed on cPA and 31% (n=115) on pPA. Acutely, there was a 14.9% (7.6 - 26.7%) improvement in stenosis in cPA, and 18.5% (9.8 - 28.6%) in pPA (p=0.053). Improvement of pressure gradient was 34.3% (10.4 - 63.4%) in cPA, and 31.6% (0 - 60.7%) in pPA (p=0.324). Higher rates of RI was seen in pPA (55% RI, p=0.035). For cPA, freedom from RI was 69% at 1 year and 44% at 5 years. Freedom from S/S was 81% at 1 year and 62% at 5 years. Factors associated with higher rate of RI include MAPCAs (65% RI, p=0.039), younger pt age (p=0.042), and lower pt weight (p=0.047). Lower rates of RI were seen in pts with discrete (p=0.007) and severe stenosis (p&lt;0.001). For pPA, freedom from RI was 59% at 1 year and 38% at 5 years. Freedom from S/S was 98% at 1 year and 92% at 5 years. Conclusions: Long term outcomes of BA for BPAS are disappointing. BA for BPAS is associated with a high rate of RI with rates exceeding 50% by 5 years. Patients with pre-hilar BPAS and with discrete, severe stenosis appear to respond more favorably. Peripheral BPAS and MAPCAs in particular have a high rate of recurrence.

Abstract 12803: Long-term Outcomes After Surgical Pulmonary Arterioplasty: Analysis of Re-intervention Rates and Patient-specific Risk Factors

Introduction: Branch pulmonary artery stenosis (PAS) is common in congenital heart disease. Surgical patch arterioplasty is a conventional therapy, however, limited data exist on long-term outcomes. Hypothesis: We examined the incidence of and risk factors for re-intervention after surgical arterioplasty for PAS. We assessed the hypothesis that certain characteristics are associated with increased need for re-intervention. Methods: This retrospective cohort study included patients with two-ventricle physiology who underwent patch arterioplasty for PAS at a single high-volume center from 2004-2013. Freedom from surgical or percutaneous re-intervention for recurrent PAS was estimated. Univariate and multivariable Cox regression were performed to determine risk factors for re-intervention. Results: Among 116 patients undergoing patch arterioplasty at a median age of 1.2 years, hospital discharge survival was 95%. Of the survivors, 97 (88%) had a median follow-up of 3.6 years (range 15 days to 11 years). PAS re-intervention occurred in 31/97 (32%) at a median time to re-intervention of 1.6 years (range 7 days to 9.3 years). Freedom from re-intervention is shown in Figure 1. In univariate analysis, age less than 30 days at time of arterioplasty, congenital PAS (versus acquired), and bilateral PAS were significantly associated with re-intervention. In multivariate analysis, neonatal age (adjusted hazard ratio [AHR 4.4], p=0.004) and bilateral PAS (AHR 3.3, p=0.003) remained independently associated with re-intervention. Conclusions: We present the largest cohort study with the longest follow-up time evaluating outcomes after surgical pulmonary arterioplasty for PAS to date. Re-intervention for recurrent PAS following patch arterioplasty is common. In conclusion, patients at highest risk for re-intervention, such as neonates and patients with bilateral PAS, may benefit from frequent monitoring or novel approaches to repair.

Abstract 11416: The “Natural History” of Intra-operative Pulmonary Artery Stents: A 20-year Perspective

Background: Branch pulmonary artery (PA) stenoses are typically treated with catheter-based percutaneous therapies or surgical arterioplasty. Intra-operative (intra-op) PA stent placement is an alternative strategy. In this study, we sought to describe our 20-year experience with intra-op PA stent placement and to evaluate long-term patient outcomes, specifically the need and risk factors for re-intervention. Methods: We performed a retrospective review of all intra-op PA stents placed at our institution from 1994-2013. Patient and stent characteristics and outcome data were collected. Risk factors associated with re-intervention were identified using univariate cox regression analysis. Results: Eighty-one PA stents were placed in 68 patients, mostly to treat proximal PA stenoses (85%). Stent implantation was acutely successful in 67 patients (98.5%) with a procedural complication rate of 4.4%. Stents capable of being dilated to large diameters (“adult-size”) were used in 97% of patients. At hospital discharge, 93% of patients had no or mild residual PA stenosis by echocardiogram. During a median follow-up period of 6 years (interquartile range 0.9-12.7), 31 patients (46%) underwent PA re-intervention with a median time to first re-intervention of 2.5 years. Risk factors for re-intervention included age &lt; 18 months (Hazard ratio [HR] 3.26, p=0.002) and body surface area &lt; 0.47 m2 (HR 3.47, p=0.001) at the time of stent implantation, and the presence of multiple aorto-pulmonary collaterals in patients with tetralogy of Fallot (HR 3.19, p=0.02). Conclusions: Intra-op PA stent implantation is technically feasible with low procedural complications. It offers several advantages over transcatheter stenting, including the ability to implant adult-size stents in small patients while avoiding injury to percutaneous vessels, to position and flare stents to facilitate future percutaneous stent re-dilation, and to access the PAs directly, which shortens procedural time and eliminates radiation exposure. It also may prevent re-stenosis from scar tissue caused by patch arterioplasty. A future direct comparison of intra-op PA stenting to catheter-based stenting and surgical arterioplasty for PA stenosis is necessary.