Pulmonary Artery Stenting

Pulmonary Artery Endograft Implantation Using a Parallel Stent Grafting Technique to Enable the Treatment of a Bronchial Anastomosis Complication After Lung Transplantation

BACKGROUND

Bronchial stenosis associated with bronchial anastomosis dehiscence after lung transplantation is a catastrophic complication following lung transplantation with a paucity of therapeutic solutions.

PURPOSE

To describe an adaptation of the parallel stent grafting technique in the pulmonary arterial territory to treat this challenging situation.

RESEARCH DESIGN

This is a case report of a 52-year-old patient who presented bronchus stenosis and bronchial anastomosis dehiscence after lung transplantion. Bronchial stenting and lung retransplantation were contraindicated. Therefore, an endovascular approach using pulmonary artery endograft placement to prevent bleeding during repeated right bronchial balloon dilation was propposed. The technique consists of the deployment of an aortic extender endoprosthesis in the right main pulmonary artery and a balloon expandable stent in the upper lobe pulmonary artery (using a parallel graft configuration) through the common femoral and right internal jugular veins, respectively. Intraoperative transesophageal echocardiogram and one-lung ventilatory ventilation are needed.

RESULTS

The patient underwent a new bronchoscopy 16 days after the procedure, that showed epithelization at the previous eroded zone, enabling bronchocopic balloon dialtion to be safely performed. A post-operative contrast-enhanced CT scan revealed an adequate positioning of the stent grafts. Despite all eforts, the patient succumbed to ventilator associated pneumonia on postoperative day 108.

DATA ANALYSIS

The technique's advantages include its feasibility even in situations in which other techniques may be contraindicated and its potential use in emergencies. Its limitations include the need for experienced interventionists to perform it, and the potential risk of acute tricuspid regurgitation.

CONCLUSION

This study illustrates the early feasibility of the parallel stent grafting technique applied to the pulmonary artery territory. However, it's safety profile regarding infectious risk was not demontrated.

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

BACKGROUND

Stent implantation has become standard of care in older children and adults for treatment of branch pulmonary artery stenosis (BPAS) and coarctation aorta (CoAo). There are no stents approved or available for infants that have the potential to be dilated to adult diameters. The Minima stent was designed to fulfill this unmet need.

METHODS

Multicenter, prospective, nonrandomized early feasibility study evaluating safety and effectiveness of the Minima stent for treatment of BPAS and CoAo. Primary endpoints included: (1) successful deployment across lesion, (2) stenosis relief defined by an increase in angiographic diameter of >50% and (3) freedom from stent explant, embolization or migration at 30 days and 6 months.

RESULTS

Between 2/2022 and 5/2022, 10 pts underwent Minima stent implantation with a median age and weight of 9 months (4-43 months) and 7.6 kg (5.1-16.9 kg). Procedural success and predefined stenosis relief was achieved in all cases (CoAo [n = 4], BPAS [n = 6]). Adverse events occurred in 3 pts: transient diminished lower extremity pulse (n = 2), distal stent on-balloon displacement successfully managed in the catheterization suite (n = 1). There were no deaths or major adverse events. All patients were free from stent explant and migration at 30 days and 6 months with no evidence for significant restenosis at latest follow-up.

CONCLUSIONS

Implantation of the Renata Minima stent was safe and effective for the treatment of BPAS and CoAo in this small cohort of infants and young children during early follow-up. Based on these early results, an expanded study with longer follow-up is warranted.

Transcatheter Interventions in Patients With Adult Congenital Heart Disease

Patients with congenital heart disease now live well into adulthood because of advances in surgical techniques, improvements in medical management, and the development of novel therapeutic agents. As patients grow older into adults with congenital heart disease, many require catheter-based interventions for the treatment of residual defects, sequelae of their initial repair or palliation, or acquired heart disease. The past 3 decades have witnessed an exponential growth in both the type and number of transcatheter interventions in patients with congenital heart disease. With improvements in medical technology and device design, including the use of devices designed for the treatment of acquired valve stenosis or regurgitation, patients who previously would have required open-heart surgery for various conditions can now undergo percutaneous cardiac catheter-based procedures. Many of these procedures are complex and occur in complex patients who are best served by a multidisciplinary team. This review aims to highlight some of the currently available transcatheter interventional procedures for adults with congenital heart disease, the clinical outcomes of each intervention, and any special considerations so that the reader may better understand both the procedure and patients with adult congenital heart disease.

Evaluation of Outcomes Following Pulmonary Artery Stenting in Fibrosing Mediastinitis

PURPOSE

Fibrosing mediastinitis is a rare disease characterized by fibrosis of mediastinal structures with subsequent constriction of the bronchi and pulmonary vessels leading to potential respiratory compromise and death. Presently, there is no effective curative treatment with available treatments focused on reducing symptomology, including placement of pulmonary artery stents. Limited studies examine the use of stents in fibrosing mediastinitis. Given this knowledge gap, we assessed stent patency, hemodynamics, complications, and secondary outcomes of clinical improvement of pulmonary artery stenting for fibrosing mediastinitis.

MATERIALS AND METHODS

Nine patients with fibrosing mediastinitis and pulmonary artery stents were retrospectively identified for inclusion (six females, three males; mean age 44.17 years, range 13-68; total 13 primary stents) from 2005 to 2018. Eight patients had history of PH. All patients had dyspnea on presentation. Seven patients had ventilation/perfusion studies demonstrating impairment. Results from computed tomography and echocardiography studies were collected to assess patency and physiologic response.

RESULTS

All patients received initial angioplasty and stenting of the right pulmonary artery (10 stents). Two patients underwent additional left-sided intervention (3 stents). Stenting significantly increased lesion luminal patency (54-79%; P < 0.005) and reduced systolic pressure gradients across stenoses (mean -9.38 mmHg; P < 0.005). Primary patency at one year was 90%. Two stents received reintervention at 276 and 497 days. 89% reported improvement in dyspnea in the initial post-stenting period. There were no mortalities or major complications.

CONCLUSION

Pulmonary artery stenting improves vascular patency and provides symptomatic relief in patients with fibrosing mediastinitis.