Aortopulmonary window due to balloon angioplasty after arterial switch operation

Simultaneous Double Balloon Dilatation for Supravalvar Pulmonary Obstruction After Arterial Switch Operation

The optimal approach for supravalvar right ventricular outflow tract obstruction(RVOTO) after arterial switch operation(ASO) is unclear. The results of percutaneous balloon dilatation have been variable. We report the results of simultaneous double balloon dilation for RVOTO after ASO. Sixteen patients (1.3(0.7-3.8) years; 9.8(8.1-15.1) kgs underwent the procedure at 14(8-44.5) months after ASO. Salient technical features included placement of balloons over stiff guide-wires positioned in both branch pulmonary arteries to enable dilation of the distal-most main pulmonary artery (MPA) with high inflation pressures (~ 12-14 atmospheres) and short inflation-deflation cycles. Effective balloon size was based on the PA annulus or MPA distal to the narrowing. The final balloon: narrowest segment diameter ratio was 2.7. Following dilation, the right ventricle to systemic systolic pressure ratio decreased from 0.9 ± 0.18 to 0.52 ± 0.16 (p  < 0.001) and mean RVOT gradient from 78 ± 18 to 34 ± 13.9 mmHg (p < 0.001). Narrowest diameter improved from 5.4 ± 2.2 to 9.2 ± 2.2 mm. There were no major complications. Two patients with inadequate relief (final RV-systemic ratios: 1.03 and 0.7) were referred for surgery. At median follow up of 9 months, IQR 7-22, range 5-73, others are free of re interventions with median RVOT gradient of 42, IQR 27-49, range 21-55 mmHg. The immediate and short-term follow up results of double balloon dilatation for supravalvar RVOTO is encouraging and may avoid the need for repeat surgery in the majority of patients. Further follow up is needed to determine the long-term durability of the results.

Interventions after Arterial Switch: A Single Low Case-Volume Center Experience

Background and Objectives: With the growing population of arterial switch operation survivors, the rate of late complications associated with the operation is growing as well. The aim of this publication is to share our experience and encourage collaboration between congenital cardiac surgeons and interventional cardiologists in treating late complications after arterial switch operation. Materials and Methods: A retrospective analysis of Vilnius University Santaros Clinics Cardiothoracic Surgery Centre arterial switch operation survivors who underwent additional treatment for late neo-pulmonary artery stenosis and aortic arch obstruction between 1989 and 2019 was conducted. Results: Out of 95 arterial switch operation survivors 14 (15%) underwent 36 reinterventions. The majority were treated for neo-pulmonary stenosis. The median time from arterial switch operation to the first reintervention was 1.4 years (interquartile range, 2 months to 2.4 years). 1, 3, 5, and 10 years intervention-free survival in patients treated for neo-pulmonary stenosis and aortic arch obstruction was 98, 94, 94, and 93% vs. 95, 94, 94, and 93%, respectively. There were no complications associated with redo surgical procedures, while eight patients who underwent catheter-based interventional treatment had treatment-related complications, including one death. Conclusions: Both neo-pulmonary stenosis and aortic arch obstruction (new aortic coarctations or aortic recoarctations) tend to develop in the first decade after an arterial switch operation. Surgical and catheter-based interventional treatment with good results is possible even in a small volume center. Close collaboration of the congenital heart team (congenital cardiac surgeons and interventional cardiologists) in choosing the best treatment option for an individual patient helps to minimize the risk of potential complications.

Cardiac Arrest Secondary to Traumatic Aortopulmonary Window During Transcatheter Pulmonary Valve Implantation in Supported Ross

We present a patient with a supported Ross procedure and severe pulmonary homograft stenosis who developed cardiac arrest while undergoing transcatheter pulmonary valve replacement and was found to have a large iatrogenic aortopulmonary window. Cardiopulmonary resuscitation was initiated followed by covered stent placement, extracorporeal membrane oxygenation support, and ultimately emergent surgery with a good outcome. (Level of Difficulty: Advanced.)

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.

Iatrogenic aortopulmonary communications after transcatheter interventions on the right ventricular outflow tract or pulmonary artery: Pathophysiologic, diagnostic, and management considerations

OBJECTIVES

To investigate the spectrum, etiology, and management of traumatic aortopulmonary (AP) communications after transcatheter interventions on the pulmonary circulation.

BACKGROUND

An iatrogenic AP communication is an unusual complication after balloon pulmonary artery (PA) angioplasty or stenting, or transcatheter pulmonary valve replacement (TPVR). However, with the increasing application of transcatheter therapies for postoperative PA stenosis and right ventricular outflow tract (RVOT) dysfunction, including percutaneous pulmonary valve replacement, consideration of the etiology, diagnosis, and management of this problem is important for interventional cardiologists performing such procedures.

METHODS AND RESULTS

We present three new cases, as well as gross anatomy and histopathology data, related to AP communications after PA interventions. We also review the literature relevant to this topic. Including these new cases, there have been 18 reported cases of iatrogenic AP communication after transcatheter interventions on the PAs or RVOT, primarily patients with transposition of the great arteries who underwent PA angioplasty after an arterial switch operation, or after TPVR in patients who had undergone a Ross procedure. The likely cause of such defects is PA trauma plus distortion of the neo-aortic anastomosis resulting from angioplasty or stenting of the RVOT or central PAs, with subsequent dissection through the extravascular connective tissue and into the closely adjacent vessel through the devitalized tissue at the anastomosis.

CONCLUSIONS

Cardiologists performing PA or RVOT interventions should be aware of the possibility of a traumatic AP communication and consider this diagnosis when confronted with suggestive signs and symptoms.

Iatrogenic aortopulmonary fistula occurring after pulmonary artery balloon angioplasty: a word of caution

We describe the natural history of an adolescent patient who developed an aortopulmonary fistula (APF) after transcatheter stent placement for left pulmonary artery stenosis after neonatal repair of d-transposition of the great arteries. Due to its rarity, the APF was not initially diagnosed and treated until 4 months later. The APF was occluded with a covered stent. Because this is not an isolated report in the literature, we believe it should be considered as a potential complication in all patients after balloon dilation of stenotic pulmonary artery branches after arterial switch surgery.