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

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

Outcomes of Surgical Reimplantation for Anomalous Origin of One Pulmonary Artery From the Aorta.

BACKGROUND: Anomalous origin of one pulmonary artery from the ascending aorta (AOPA) is a rare and potentially deadly anomaly. Little research, aside from case reports on APOA, has been published, especially for patients with late referrals. METHODS: This study was a retrospective review of 57 patients with AOPA who underwent reimplantation of the pulmonary artery (PA) from 2009 to 2019. Two different reimplantation methods were used to correct the anomaly, including direct anastomosis in 36 patients and angioplasty with autologous tissue in 21 patients. RESULTS: The median age at repair was 2.8 months (range, 8 days to 3.6 years). In-hospital death occurred in 2 patients (3.5%). Five patients (9.1%) with a median age of 9.3 months (range, 5.2 months to 3.6 years) experienced a pulmonary hypertensive crisis. Patients older than 4.9 months were more likely to have a pulmonary hypertensive crisis (P = .001). The 2-year freedom from postoperative PA stenosis rate was 75.3% in patients who underwent direct anastomosis and 46.8% in patients who underwent autologous tissue angioplasty (χ2 = 4.878; P = .027). Angioplasty with autologous tissue (hazard ratio, 5.03; 95% confidence interval, 1.61 to 15.71; P = .005) and an innately smaller diameter of the aberrant PA (hazard ratio, 0.65; 95% confidence interval, 0.45 to 0.92; P = .015) were 2 independent risk factors for postoperative PA stenosis. CONCLUSIONS: Surgical reimplantation of the PA in patients with AOPA has resulted in favorable early and midterm outcomes. Pulmonary hypertensive crisis occurs more commonly in patients who receive a diagnosis after the age of 4.9 months. Reimplantation with autologous tissue augmentation and an intrinsically smaller diameter in affected PAs are 2 independent risk factors for postoperative PA stenosis.

Pneumonectomy is necessary following delayed detection of pulmonary artery compromise.

It has been previously suggested that lung tissue remains viable without blood supply from the pulmonary artery (PA). However, our experience demonstrates otherwise. We present 2 cases of accidental left lower lobe PA occlusion during upper lobectomy causing ischaemic changes to the remaining lung tissue. Both patients became septic secondary to necrosis of infarcted lung and required completion pneumonectomy. Development of collateral circulation to bypass the occluded PA may occur but is often insufficient to support the affected lung tissue. Unless the patient is medically unfit, resection of the ischaemic lung should be undertaken.

Obstructing Granuloma in Main Pulmonary Trunk.

A patient with main pulmonary artery mass may have severe symptoms and warrants urgent surgical management, whereas in a stable patient with a diagnosis amenable to medical treatment, medical management should be started while monitoring the size of the lesion. We report a case in which the patient experienced severe right heart dysfunction due to obstruction of the main pulmonary artery, diagnosed as a probable thrombus, and the patient was taken for urgent surgical excision, later diagnosed as tuberculoma on histopathologic examination.

Diagnostic Dilemma in a Case of Diffuse Pulmonary Arteriovenous Malformation With Vascular Stenosis.

Diffuse pulmonary arteriovenous malformation is a rare entity, the exact incidence of which is unknown. It can be limited to a single lobe, or it can diffusely involve one or both the lungs. Early diagnosis and treatment is crucial, as it is associated with increased frequency of thoracic and neurologic complications. Different diagnostic modalities offer some advantages over the others. None of the reported cases in the literature have associated stenosis of any major artery. We describe a rare case of diffuse pulmonary arteriovenous malformation limited to a lobe associated with descending pulmonary artery stenosis.

Pulmonary artery interventions after the arterial switch operation: Unique and significant risks.

BACKGROUND: In the modern era, results of the arterial switch operation (ASO) for transposition of the great arteries are excellent. However, because of the LeCompte maneuver, there may be a propensity for development of pulmonary artery stenosis. We encountered atypical complications of pulmonary artery stenting in patients after the ASO, including aorto-pulmonary fistula and coronary compression. METHODS: We performed a 10-year retrospective review of catheterizations performed in patients after ASO in our institution with a focus on adverse events. RESULTS: Diagnostic and interventional catheterizations were performed in 47 patients. In 29 patients, 37 interventional procedures performed, which included pulmonary artery angioplasty and/or stenting. In this group, there were five major adverse events (14%), including three aorto-pulmonary fistulae and one coronary artery compression among patients having stent implantation or stent redilation. In addition, there were 6/37 (16%) intended stent procedures, which were aborted because there appeared to be high-risk of significant adverse events. CONCLUSIONS: This review suggests that percutaneous intervention on pulmonary artery stenosis after ASO has high-risk and should be undertaken advisedly. Prior thorough evaluation of coronary arteries is mandatory as coronary reimplantation sites may be adjacent to sites of pulmonary artery stenosis. Furthermore, if pulmonary artery stent implantation or stent redilation is contemplated, the risk of stent fracture and possible AP fistula should be recognized. Primary use of reinforced covered stents should be considered.

Pulmonary Perfusion Using Intrabronchial Capnography in Pulmonary Artery Stenosis.

Stenting at the flow-limiting segment can improve the ventilation-perfusion ratio in patients with central airway stenosis. However, there is no quantitative examination for assessing the perfusion status during interventional bronchoscopy. Intrabronchial capnography can estimate regional gas exchange by measuring carbon dioxide concentration. We herein report a case of bilateral bronchial stenosis where stenting was able to improve ventilation-perfusion ratio using intrabronchial capnography. A 44-year-old man was admitted to our institution with orthopnea. Chest computed tomography showed an extrinsic compression at the bilateral main bronchus and right pulmonary artery due to a mediastinal mass. After introduction of general anesthesia, arterial oxygen tension suddenly decreased in the supine position. After initial stenting, an increase was seen in ventilation at the right lung; however, a ventilation-perfusion mismatch occurred due to an increase in dead-space ventilation at the right pulmonary artery stenosis. Intrabronchial capnography was an effective modality to confirm the regional perfusion status during interventional bronchoscopy in real time.

Successful Infant Pneumonectomy with Unilateral Pulmonary Artery Occlusion Test.

The use of unilateral pulmonary artery occlusion (UPAO) test for the preoperative evaluation of pneumonectomy was reported in adult patients. On the contrary, in infants, no strategies have yet been recommended to predict hemodynamics after pneumonectomy, nor has use of the UPAO test been reported. We describe the first case of infant with abnormal pulmonary circulation in whom successful pneumonectomy was performed after preoperative evaluation using UPAO test. Right pneumonectomy was planned for an 8-month-old girl, because of decreased right pulmonary function, high risk of pneumothorax, and impaired left lung expansion due to overexpansion caused by severe left bronchial stenosis and bronchomalacia. However, she had also prolonged pulmonary hypertension and there was difficulty in accurate echocardiographic evaluation of its severity due to concomitant left pulmonary artery stenosis. Furthermore, contrast-enhanced computer tomography suggested a certain degree of right pulmonary venous flow, discordant with the result showing scarce right pulmonary flow in perfusion scintigraphy. Predicting postoperative hemodynamic changes was therefore considered difficult. To evaluate these concerns, we performed cardiac catheterization and UPAO test to simulate postoperative hemodynamics. Pulmonary arteriography showed decreased but significant right pulmonary arterial and venous flows. Measurements including pulmonary artery pressure and cardiac index showed no marked changes after occlusion. Based on UPAO test results, the operation was successfully performed and hemodynamics remained stable postoperatively. The UPAO test may be useful for infants with cardiopulmonary impairment to evaluate the tolerability of pneumonectomy.

Computational simulation of postoperative pulmonary flow distribution in Alagille patients with peripheral pulmonary artery stenosis.

BACKGROUND: Up to 90% of individuals with Alagille syndrome have congenital heart diseases. Peripheral pulmonary artery stenosis (PPS), resulting in right ventricular hypertension and pulmonary flow disparity, is one of the most common abnormalities, yet the hemodynamic effects are ill-defined, and optimal patient management and treatment strategies are not well established. The purpose of this pilot study is to use recently refined computational simulation in the setting of multiple surgical strategies, to examine the influence of pulmonary artery reconstruction on hemodynamics in this population. MATERIALS AND METHODS: Based on computed tomography angiography and cardiac catheterization data, preoperative pulmonary artery models were constructed for 4 patients with Alagille syndrome with PPS (all male, age range: 0.6-2.9 years), and flow simulations with deformable walls were performed. Surgeon directed virtual surgery, mimicking the surgical procedure, was then performed to derive postoperative models. Postoperative simulation-derived hemodynamics and blood flow distribution were then compared with the clinical results. RESULTS: Simulations confirmed substantial resistance, resulting from preoperative severe ostial stenoses, and the use of newly developed adaptive outflow boundary conditions led to excellent agreement with in vivo measurements. Relief of PPS decreased pulmonary artery pressures and improved pulmonary flow distribution both in vivo and in silico with good correlation. CONCLUSIONS: Using adaptive outflow boundary conditions, computational simulations can estimate postoperative overall pulmonary flow distribution in patients with Alagille syndrome after pulmonary artery reconstruction. Obstruction relief along with pulmonary artery vasodilation determines postoperative pulmonary flow distribution and newer methods can incorporate these physiologic changes. Evolving blood flow simulations may be useful in surgical or transcatheter planning and in understanding the complex interplay among various obstructions in patients with peripheral pulmonary stenosis.

Unilateral pulmonary artery pre-operative occlusion test: technical feasibility and safety prior to pneumonectomy or pleuropneumonectomy for malignancy.

OBJECTIVE: The aim of the present study was to assess the technical feasibility and safety of the unilateral pulmonary artery occlusion (UPAO) test in pre-operative evaluation of pneumonectomy or pleuropneumonectomy for lung or pleural tumours. METHODS: The UPAO test was performed on 91 patients who were scheduled to undergo or were being considered for pneumonectomy or pleuropneumonectomy between June 2003 and July 2016. There were 74 males and 17 females, with a median age of 65 years (range, 23-80). The technical success rate, procedure time and complication rate were evaluated. Technical success was defined as completion of the UPAO test. RESULTS: The diagnoses of the 91 patients were as follows: lung cancer in 63, malignant pleural mesothelioma in 21, thymoma in 5, lung metastasis in 1 and lung carcinoid in 1. The UPAO test was performed successfully on 88 out of 91 patients (technical success rate: 97%). The median procedure time was 57 min (range, 34-120). Cardiac arrest due to migration of the balloon catheter to the pulmonary trunk occurred in 1 patient (complication rate: 1.1%). CONCLUSION: The UPAO test in pre-operative evaluation of pneumonectomy or pleuropneumonectomy for lung or pleural tumours appears to be technically feasible. However, it needs to be performed with care in order to avoid severe complications. Advances in knowledge: The UPAO test can be safely performed and is helpful in evaluating patients for pneumonectomy or pleuropneumonectomy.

Treatment of Severe Native Left Pulmonary Artery Stenosis With Coronary Stent Implantation in a 2.4 kg Neonate.

A 1-month-old, 2.4 kg infant, previously born at 32 weeks gestation, was found to have a murmur while in the neonatal intensive care unit. The patient had ongoing feeding intolerance and required supplemental oxygen via nasal cannula. Cardiac computed tomography showed discrete stenosis of the proximal left pulmonary artery (LPA) with a normal-sized distal LPA. We describe the treatment course with transcatheter coronary stent implantation.

Lung Abscess as Delayed Manifestation of Pulmonary Arterial Narrowing After Sleeve Resection.

A patient who had undergone right upper bilobectomy because of a carcinoid experienced lung abscesses 17 months after operation. After recurrences, despite different antibiotic agents, dual-energy computed tomography showed subtotal stenosis of the right lower lobe pulmonary artery with marked pulmonary perfusion-reduction. Rare causes of lung-abscesses should be considered.

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

BACKGROUND: 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. METHODS: 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). RESULTS: 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. CONCLUSIONS: Intraoperative stenting of BPA is a safe and effective option to treat BPA stenosis and prevent recurrence.

Nontuberculous mycobacterial disease concomitant with a pulmonary artery occlusion caused by Takayasu's arteritis.

We herein describe a surgical case of pulmonary involvement in Takayasu's arteritis with pulmonary infections of nontuberculous mycobacteria. A 24-year-old female was admitted to our hospital because of a recurrent fever, and contrast-enhanced computed tomography of the chest revealed the occlusion of the right pulmonary artery and cavitary lesions in the right lower lobe of the lung. A further examination of the neck revealed the occlusion of aortic branches, and the patient was diagnosed with Takayasu's arteritis. The cavitary lesions were diagnosed as nontuberculous mycobacteria disease according to the sputum culture result of Mycobacterium intracellulare. After antibiotic treatment for 6 months, the right pneumonectomy was performed with a good result. We should be aware of Takayasu's arteritis as a disease which can lead to the development of unexplained respiratory symptoms due to pulmonary artery involvement in young adults.

Surgical Technique for Repair of Peripheral Pulmonary Artery Stenosis and Other Complex Peripheral Reconstructions.

Surgical reconstruction of peripheral pulmonary artery stenosis is a technically challenging procedure due to the need to access all lobar and segmental branches. This paper describes our surgical approach that entails division of the main pulmonary and separation of the branch pulmonary arteries. This surgical approach can also be utilized for other complex peripheral pulmonary artery reconstructions.