Transcatheter pulmonary valve implant in a patient with a previous pulmonary valve-in-valve

Abstract

Increasing numbers of patients with congenital heart disease now survive well into adulthood. Often, these patients already had surgery to correct their congenital lesions from early life. Patients with tetralogy of Fallot commonly require several pulmonary valve replacements in their lifetime. This report highlights the utility of percutaneous pulmonary valve implant inside the two prior prosthetic valves avoiding a third sternotomy, in a young adult patient who developed severe prosthetic pulmonary valve stenosis.

Learning objective

To understand the potential therapeutic option of transcatheter pulmonary valve implant inside a dilatable stented surgical bioprosthesis with an existing valve-in-valve in situ as part of lifetime management.

Introduction

Due to advancements in medical and surgical treatment, most patients with congenital heart disease now survive into adulthood. Post-operative congenital heart disease patients with right ventricle to pulmonary artery (RV to PA) conduits or bioprosthetic pulmonary valves will often require re-intervention. Transcatheter pulmonary valve implantation (TPVI) was developed to meet such needs [1]. For patients requiring RV outflow tract re-intervention with a history of prior repaired tetralogy of Fallot or RV to PA conduit, TPVI is now the preferred treatment to preserve RV function and reduce the lifetime burden of repeated sternotomy [2]. However, even post TPVI, up to 25% would require re-intervention over a 10-year period [3]. For such patients, a valve-in-valve re-intervention could be a reasonable alternative to replacement surgery over medium-term follow-up [4,5]. However even such patient groups will eventually develop valve dysfunction in the transcatheter valve. Here, we describe a case of TPVI in a patient who already had a valve-in-valve and we undertook valve-in-valve-in valve as an alternative strategy to defer a third sternotomy and surgical pulmonary valve replacement (PVR).

Case report

A 26-year-old female born with a tetralogy of Fallot had severe pulmonary regurgitation after the first surgical repair, needing a second operation at age 8 years with a 23 mm Carpentier Edwards Perimount bioprosthesis (Edwards Lifesciences, Irvine, CA, USA).

At age 14 years, she developed severe prosthetic valve pulmonary stenosis (PS) needing a 22 mm Melody (Medtronic, Minneapolis, MN, USA) valve-in-valve. Post-dilation was done with 22 mm Mullins-X (NuMed, Orlando, FL, USA) up to 8 atm.

At age 24 years, she had an episode of bacteraemia which resolved with antibiotics with no lesions seen on computed tomography and transoesophageal echocardiogram. Two years later, she developed dyspnoea with severe PS and mild pulmonary regurgitation in the Melody valve (Online data S1). In the multidisciplinary meeting, given the two prior sternotomies and good medium-term performance of the Melody valve implanted 12 years earlier, a second percutaneous Melody valve implant was planned. The procedure was performed under a general anaesthesia. At the start of the procedure the systemic blood pressure was 112/64 mm Hg, with the RV systolic pressure (RVSP) of 64 mm Hg with a peak-to-peak gradient across the pulmonary valve of 28 mm Hg under general anaesthesia. A 25 mm True™ Balloon (BD, Franklin Lakes, NJ, USA) was used at high pressure of 20 ATM to break the ring of the old surgical valve and over-dilate the previous Melody valve stent, to maximise the internal diameter (Fig. 1A–C, Online data S2–3). This was followed by implantation of a 22 mm Melody valve premounted on a 22 mm Ensemble (Medtronic, Minneapolis, MN, USA). The valve was post dilated with a 22 mm Atlas™ Gold (BD, Franklin Lakes, NJ, USA) inflated to a pressure of 16 ATM (Fig. 1D–F, Online data S4–5). This reduced the RVSP to 42 mm Hg and the transvalvar peak to peak gradient to 8 mm Hg. She was discharged home the next day.

Fig. 1.

(A) Preprocedural hemodynamics showing a systemic pressure of 112/64 mm Hg, right ventricular systolic pressure (RVSP) of 64 mm Hg with a pulmonary artery to right ventricle (PA-RV) gradient of 28 mm Hg. (B) Previous Melody valve inside a 23 mm C.E. Perimount bioprosthesis. The patient's first valve-in-valve procedure involved Melody valve on 22 mm balloon-in-balloon (BIB) which was post dilated with Mullins-X balloon 22 mm at 8 atm. A post stenotic dilatation of the main pulmonary artery is noted. (C) Pre-dilatation with a 25 mm True Balloon. The previous valves were dilated to maximise their inner diameter. The previous Melody valve stent height was foreshortened significantly. (D) A 22 mm Melody valve implant inside the previous valve-in-valve. (E) Angiogram post dilatation of the new Melody 22 mm valve inside a previous Melody valve inside a previous 23 mm C.E. Perimount bioprosthesis with minimal pulmonary regurgitation. (F) Final tracing showing RVSP of 42 mm Hg and PA-RV gradient of 8 mm Hg after valve-in-valve-in-valve.

Discussion

The first transcatheter pulmonary valve implantation was performed in 2000 by Philip Bonhoeffer [1]. This bovine jugular valve, mounted in a CP stent (platinum iridium alloy), became the Melody transcatheter pulmonary valve designed to treat degenerated right ventricular to pulmonary artery conduits [[6], [7], [8]] achieving equivalent outcomes to surgical PVR over 10-year follow up [9]. There are previous reports showing feasibility of Melody valve implant in stented bioprosthetic surgical valves [4,5]. However, long-term follow up data are lacking currently. A one-year outcome of such a patient population was reported by Gillespie et al. where 2 stent fractures and 3 cases of endocarditis were found in 104 patients who had Melody valve-in-valve [4]. In our patient, there were 10 years of event-free survival after the initial Melody valve in-valve which is notable and shows that a Melody valve inside a stented surgical valve, can achieve at least medium-term durability.

Our patient then had bacteraemia which was managed medically with antibiotics and the valve functioned for two additional years. The patient then was brought back for a valve-in-valve-valve instead of a surgical PVR. The decision was based on the presence of Perimount valve, the ring of which can be overdilated, to achieve a better valve area, and the knowledge that the Melody valve stent, can also be overdilated, a desire to avoid a third sternotomy at a young age, and the durability of the original Melody valve-in-valve. To our knowledge, this has not been described previously. For this patient, pulmonary valvuloplasty alone was not considered due to the presence of pulmonary regurgitation. In the context of degenerative prosthetic leaflets, even though in this case, a bovine jugular venous valve, are in our view less likely to respond favourably to valvuloplasty. We arrived at this conclusion as there were no reported cases of a successful valvuloplasty alone for a dysfunctional Melody valve. Similarly, no reported cases were found describing successful valvuloplasty alone for a degenerated Contegra conduit (Medtronic Inc.) which has a bovine jugular venous valve like the Melody Valve. Hence, we decided to insert a new valve to both deal with stenosis and regurgitation and avoid the possibility of prosthetic leaflet damage or distal embolization. In addition, the patient's first valve-in-valve was performed in 2008 with Melody on 22 mm BIB. Breaking the ring of the surgical prosthetic valve was not performed in 2008 because this concept was unavailable at least until 2014 from our knowledge [9]. Post dilation done with Mullins-X 22 mm at 8 atm would not have broken the 23 mm Perimount. Hence, we knew the ring of the previous surgical valve needed to be broken during our procedure, to maximise the internal diameter of the new valve.

The Perimount valve is constructed such that it is safe to overdilate the metal valve ring, such that the internal diameter is improved, without disrupting the sewing ring [9]. Furthermore, the Melody valve is mounted in a 34 mm CP stent, that can also be overdilated, causing it to shorten dramatically, but again facilitates enlargement of the functional valve area of the new valve mounted inside the entire complex. In contrast, some other surgical valves, such as the Hancock valved conduit (Medtronic), or Hancock 2 valve (Medtronic), cannot be overdilated, and the Edwards Sapien 3 valve (Edwards Lifesciences) can only be overdilated up to a point.

In a well-selected patient with the presence of a dilatable initial surgical valve, and particularly if a Melody valve has been implanted, that is also overdilatable, this approach seemed a reasonable alternative to surgery as part of the lifetime management of the patient. Ensuring maximum valve area, in turn minimises turbulence, optimises cardiovascular performance, and is likely to minimise the risk of endocarditis via low residual gradient [10].

Declaration of competing interest

The authors declare that there is no conflict of interest.

Appendix A. Supplementary data

Supplementary figures