Procedural technique for hybrid pulmonary valve replacement in infants and small children

Current status of transcatheter intervention for complex right ventricular outflow tract abnormalities

Various transcatheter interventions for the right ventricular outflow tract (RVOT) have been introduced and developed in recent decades. Transcatheter pulmonary valve perforation was first introduced in the 1990s. Radiofrequency wire perforation has been the approach of choice for membranous pulmonary atresia in newborns, with high success rates, although complication rates remain relatively common. Stenting of the RVOT is a novel palliative treatment that may improve hemodynamics in neonatal patients with reduced pulmonary blood flow and RVOT obstruction. Whether this option is superior to other surgical palliative strategies or early primary repair of tetralogy of Fallot remains unclear. Transcatheter pulmonary valve replacement has been one of the biggest innovations in the last two decades. With the success of the Melody and SAPIEN valves, this technique has evolved into the gold standard therapy for RVOT abnormalities with excellent procedural safety and efficacy. Challenges remain in managing the wide heterogeneity of postoperative lesions seen in RVOT, and various technical modifications, such as pre-stenting, valve ring modification, or development of self-expanding systems, have been made. Recent large studies have revealed outcomes comparable to those of surgery, with less morbidity. Further experience and multicenter studies and registries to compare the outcomes of various strategies are necessary, with the ultimate goal of a single-step, minimally invasive approach offering the best longer-term anatomical and physiological results.

Hybrid approach for harmony transcatheter pulmonary valve replacement

The Harmony™ Transcatheter Pulmonary Valve (Medtronic) was recently approved by the Food and Drug Administration for transcatheter pulmonary valve replacement in native right ventricular outflow tracts. Despite this milestone, some patients have main pulmonary arteries that are severely dilated and continue to require surgical pulmonary valve replacement. The hybrid approach combines surgical creation of a landing zone, transcatheter valve deployment, and suture stabilization of the implanted valve. In this case series, we report the first use of a hybrid approach for Harmony™ transcatheter pulmonary valve replacement. Two cases are reported with varying approaches for surgical creation of a landing zone followed by successful placement of a Harmony™ valve.

Ten Years of Percutaneous Pulmonary Valve Implantation in Australia and New Zealand

OBJECTIVE

This study sought to investigate the characteristics, morbidity (including the rate of infective endocarditis and valve replacement) and mortality of individuals undergoing percutaneous pulmonary valve implantation in Australia and New Zealand since the procedure has been performed.

BACKGROUND

The outcomes of percutaneous pulmonary valve implantation in Australia and New Zealand have not been evaluated. Recent international data, including patients from New Zealand, suggests the rate of infective endocarditis is not insignificant.

METHODS

A retrospective multi-site cohort study was undertaken via medical record review at the centres where percutaneous pulmonary valve implantation has been performed. All procedures performed from 2009-March 2018 were included. Individuals were identified from local institution databases. Data was collected and analysed including demographics, details at the time of intervention, haemodynamic outcome, post procedure morbidity and mortality. Multi-site ethics approval was obtained.

RESULTS

One hundred and seventy-nine (179) patients attended the cardiac catheter laboratory for planned percutaneous pulmonary valve implantation. Of these patients, 172 underwent successful implantation. Tetralogy of Fallot and pulmonary atresia were the most common diagnoses. The median age at procedure was 19 years (range 3-60 yrs). There was a significant improvement in the acute haemodynamics in patients undergoing percutaneous pulmonary valve implantation for stenosis. Seven (7) patients (3.9%) experienced a major procedural/early post procedure complication (death, conversion to open procedure, cardiac arrest), including two deaths. The annualised rates of infective endocarditis and valve replacement were 4.6% and 3.8% respectively. There was one death related to infective endocarditis in follow-up.

CONCLUSIONS

Percutaneous pulmonary valve replacement is a relatively safe method of rehabilitating the right ventricular outflow tract.

Single‐Center Experience of Hybrid Pulmonary Valve Replacement Using Left Anterior Thoracotomy With Pulmonary Artery Plication in Patients With Large Right Ventricular Outflow Tract

Background

Until recently, a large right ventricle outflow tract interfered with the feasibility of standard transcatheter pulmonary valve replacement (PVR). We are describing our experience using a hybrid approach for PVR using a left anterior thoracotomy approach to allow for plication of the main pulmonary artery followed by a transcatheter PVR using a Sapien S3 valve.

Methods and Results

This is a single‐center, retrospective review of patients who were evaluated to be appropriate for a hybrid PVR approach. The patients' demographics, procedure details, and follow‐up data were collected. Between May 2018 and April 2021, a total of 11 patients presented for hybrid transcatheter PVR. The median age and weight were 24 years (interquartile range, 19–43 years) and 81.8 kg (interquartile range, 69–91 kg), respectively. Nine out of 11 patients received a transcatheter PVR after main pulmonary artery plication. There were no procedurally related deaths. One major complication was encountered in which the valve was malpositioned requiring successful surgical PVR. Minor complications included acute kidney injury (n=1) and a broken rib (n=1). The median length of stay was 4 days (interquartile range, 2–4 days), with median follow‐up of 7 months (interquartile range, 3–18 months). A well‐functioning pulmonary valve was observed in all patients at the last follow‐up.

Conclusions

A hybrid approach using left anterior thoracotomy with pulmonary artery plication followed by transcatheter Sapien S3 PVR provides a less‐invasive option for patients with an enlarged right ventricular outflow tract. Preliminary results demonstrated this to be a safe option with good short‐term outcomes.