Melody valve implant within failed bioprosthetic valves in the pulmonary position: a multicenter experience

Infective endocarditis of a transcatheter pulmonary valve in comparison with surgical implants

BACKGROUND

Melody valved stents (Medtronic Inc, Minneapolis, Minnesota, USA) have become a very competitive therapeutic option for pulmonary valve replacement in patients with congenital heart disease. After adequate prestenting of the right ventricular outflow tract (RVOT) Melody valved stents have a good medium term functional result but are exposed to infective endocarditis (IE).

PATIENTS AND METHODS

Retrospective study of tertiary centre Congenital Heart Disease database; to compare incidence of IE in three different types of valved conduits in RVOT: Melody valved stent, cryopreserved homograft (European Homograft Bank) and Contegra graft (Medtronic Inc).

RESULTS

Between 1989 and 2013, 738 conduits were implanted in 677 patients. 107 Melody valved stents were implanted in 107 patients; IE occurred in 8 (7.5%) patients during a follow-up of 2.0 years (IQR 2.4 years, range 0.3-7.8 years). 577 Homografts were implanted in 517 patients; IE occurred in 14 patients (2.4%) during a median follow-up of 6.5 years (IQR 9.2 years; range 0.1-23.7 years). Finally, 54 Contegra grafts were implanted in 53 patients; 11 patients (20.4%) had IE during a follow-up of 8.8 years (IQR 7.7 years; range 0.2-3.5 years). Survival free of IE by Kaplan-Meier for homografts was 98.7% at 5 years and 97.3% at 10 years; for Contegra 87.8% at 5 years and 77.3% at 10 years and for Melody 84.9% at 5 years (log-rank test; p<0.001).

CONCLUSIONS

The Contegra conduit and Melody valved stents have a significantly higher incidence of IE than homografts. IE is a significant threat for long-term conduit function.

A new percutaneous pulmonary valve implantation technique for complex right ventricular outflow tracts: the "folded melody valve"

OBJECTIVES

This article sought to describe a new modification of the Melody valve that allows percutaneous pulmonary valve implantation (PPVI) in complex outflow tracts.

BACKGROUND

PPVI has been validated as a valuable therapeutic option for the management of patients with dysfunctional right ventricular outflow tracts (RVOT). However, complex and unfavourable RVOT anatomy continue to limit the indications for PPVI.

METHODS

Between April 2012 and November 2013, PPVI was performed in 10 patients (mean age = 16, 3 ± 5 years old) using a new modification of the Melody® valve consisting in a manual shortening of the Melody by folding the two extremities of the stent. We reviewed the results of this technique.

RESULTS

Indications were short RVOT in three patients, prevention of retrosternal compression in two patients, bioprosthetic valves in four and coronary arteries proximity in one. No complication occurred during procedures. All patients had excellent hemodynamic results [mean post PPVI RV-PA gradient was 14 ± 6 mm Hg, three patients had trivial pulmonary regurgitation (PR) and the remaining had no PR]. After a mean follow-up of 11 months (range 5-21 months), no patient had reintervention. No valve dysfunction or stent fractures were observed.

CONCLUSION

The "Folded valve technique" is a safe modification of the Melody valve. By shortening the valve, this technique allowed PPVI in short and complex RVOTs with vulnerable neighborhood.

Transcatheter pulmonary valve insertion, expanded use (beyond large conduits from the right ventricle to pulmonary artery), and future directions

Transcatheter pulmonary valve insertion is the most important advance in congenital interventional cardiology since atrial septal defect devices became commonly available 15 years ago. It has changed the way we look at a number of diverse diagnoses and changes how we plan, diagnose, operate, and follow-up patients. It has changed how we counsel families expecting a child that may benefit from it. Expanded use of the Melody® valve, outside its United States Food and Drug Administration approved indications, has helped numerous additional patients. The use of transcatheter pulmonary valve insertion in selected patients following surgical Gore-tex® bileaflet in valve right ventricular outflow tract reconstruction and those with a history of prior small homograft conduits will be discussed.

Will catheter interventions replace surgery for valve abnormalities?

PURPOSE OF REVIEW

Catheter-based valve technologies have evolved rapidly over the last decade. Transcatheter aortic valve replacement (TAVR) has become a routine procedure in high-risk adult patients with calcific aortic stenosis. In patients with congenital heart disease (CHD), transcatheter pulmonary valve replacement represents a transformative technology for right ventricular outflow tract dysfunction with the potential to expand to other indications. This review aims to summarize the current state-of-the-art for transcatheter valve replacement (TVR) in CHD; the expanding indications for TVR; and the technological obstacles to optimizing TVR.

RECENT FINDINGS

Multiple case series have demonstrated that TVR with the Melody transcatheter pulmonary valve in properly selected patients is safe, effective, and durable in short-term follow-up. The Sapien transcatheter heart valve represents an alternative device with similar safety and efficacy in limited studies. Innovative use of current valves has demonstrated the flexibility of TVR, while highlighting the need for devices to address the broad range of postoperative anatomies either with a single device or with strategies to prepare the outflow tract for subsequent device deployment.

SUMMARY

The potential of TVR has not been fully realized, but holds promise in treatment of CHD.

The Ross procedure: suitable for everyone?

In 1967, Donald Ross transferred the patient's own pulmonary valve into the aortic root. Although results of this technique were encouraging, the Ross procedure did not gain widespread popularity until the late 1980s when surgeons started to implant the pulmonary autograft as a freestanding full root replacement with reimplantation of the coronary arteries. However, frequent dilatation of the pulmonary autograft was observed using the freestanding full root replacement technique. In contrast, the original subcoronary implantation technique and aortic root inclusion technique prevented dilatation in the long-term. Through advancing know-how in aortic root surgery and confidence, the Ross procedure has also been used in combined procedures and complex clinical presentations with good long-term results, which encourage continual use. However, the Ross procedure is a complex operation; careful patient selection and experience of the surgeon are mandatory requirements to achieve satisfactory results.

Caring for a teen with congenital heart disease

Adolescents with congenital heart disease (CHD) are a rapidly growing population with complex medical needs and psychosocial challenges. Identity formation is an important developmental task accomplished during the teenage years. This article reviews different aspects of ongoing care that pertain to teenagers with CHD, with a particular focus on primary care issues and a summary of recommendations from various scientific societies. A successful smooth transition to the adult health care setting should achieve 2 important goals: to prevent loss of follow-up and to foster and encourage self-care behaviors.

Transcatheter pulmonary valve insertion, expanded use and future directions

Transcatheter pulmonary valve replacement with the Melody® valve is an accepted alternative to surgical replacement of the pulmonary valve for some patients and therefore a complementary strategy in the long-term management of several groups of patients with congenital heart disease. It allows at least extending the time between sternotomies and possibly improving late outcomes. With a combined surgical and percutaneous approach, late morbidity for some of these patients will likely be diminished. This manuscript will review the current expanded applications for this technology, demonstrate several examples of its use and discuss future directions for this evolving equipment.

Percutaneous options for heart failure in adults with congenital heart disease

In the context of congenital heart disease (CHD), the complex biochemical and physiologic response to the pressure- or volume-loaded ventricle can be induced by stenotic and shunt/regurgitant lesions, respectively. A range of transcatheter therapies have recently emerged to expand the therapeutic potential of the more traditional surgical and medical interventions for heart failure in patients with CHD. Together, these complementary interventions aim to treat the growing patient population with adult CHD (ACHD). In this article, the most commonly used transcatheter interventions for heart failure in patients with ACHD are reviewed.

Infective endocarditis following percutaneous pulmonary valve replacement: diagnostic challenges and application of intra-cardiac echocardiography

BACKGROUND

Infective endocarditis (IE) following percutaneous pulmonary valve replacement (PPVR) with the Melody valve is rarely reported. Furthermore, there are challenges in this diagnosis; especially echocardiographic evidence of vegetation within the prosthesis may be difficult.

METHOD AND RESULT

This study is a retrospective review of all patients with Melody valve implantation in a tertiary centre. Between November 2006 and November 2012, 43 procedures were performed in 42 patients (mean age 25 years, 6-67 years). At a median follow-up of 27 months (2-66 months), six patients were suspected for IE. However, repeated transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) showed no evidence of IE and the patients were diagnosed as possible cases according to the modified Duke's criteria. Two patients did not respond to antibiotic treatment and underwent intra-cardiac echocardiography (ICE), which clearly demonstrated vegetations. These two cases required surgical explantation, while the other four patients were treated medically without complications.

CONCLUSION

IE after Melody valve implantation is uncommon, but difficult to verify since TTE and TEE often cannot demonstrate vegetations inside the stent. ICE should be considered in suspected cases of IE following PPVR with negative TTE and TEE examinations in order to early tailor the best treatment for the individual patient suspected for IE.

Update of transcatheter valve treatment

Transcatheter valve implantation or repair has been a very promising approach for the treatment of valvular heart diseases since transcatheter aortic valve implantation (TAVI) was successfully performed in 2002. Great achievements have been made in this field (especially TAVI and transcatheter mitral valve repair--MitraClip system) in recent years. Evidence from clinical trials or registry studies has proved that transcatheter valve treatment for valvular heart diseases is safe and effective in surgical high-risk or inoperable patients. As the evidence accumulates, transcatheter valve treatment might be an alterative surgery for younger patients with surgically low or intermediate risk valvular heart diseases in the near future. In this paper, the updates on transcatheter valve treatment are reviewed.

The Melody® valve and Ensemble® delivery system for transcatheter pulmonary valve replacement

The Melody® transcatheter pulmonary valve (TPV) is a percutaneous valve system designed for the treatment of obstruction and/or regurgitation of prosthetic conduits placed between the right ventricle and pulmonary arteries in patients with congenital heart disease. In 2000, Melody TPV became the first transcatheter valve implanted in a human; in 2006 it became the first transcatheter valve commercially available anywhere in the world; and in 2010 it was launched as the first commercially available transcatheter valve in the United States. In this review, we present the clinical background against which the Melody valve was developed and implemented, introduce the rationale for and challenges of transcatheter valve technology for this population, outline the history and technical details of its development and use, and summarize currently available data concerning the performance of the device.