The authors conducted a retrospective review (2012 to 2018) of patients from seven European centers who underwent percutaneous Melody valve implantation using the “folded valve technique.” The terminal stent struts are folded on either side of the valve, which decreases the length of the device from 24.6 mm to 20.9 mm if one end is folded and 16.7 mm if both ends are folded. The indications for this technique were: 

• Short RVOT with early pulmonary artery bifurcation 
• Bioprosthetic valves 
• Coronary artery proximity 
• Prevention of sternal compression 

The review included 49 patients (median age 19 years). RVOT presenting was performed in 43 patients (89%). Five patients had trivial pulmonary insufficiency immediately post-implantation, while the remaining had none. During a median follow-up of 28 months (137 patient years), 40/47 patients remained symptom-free. The mean RVOT at the last transthoracic echocardiogram was 15 mm Hg (Post implant was 13). 45/47 patients were free of pulmonary insufficiency, with 2 having trivial regurgitation. Three patients underwent valve-related interventions (2.1% incidence per patient year). Two patients developed infective endocarditis (1.4% incidence per patient year). Previous studies have reported incidences of infective endocarditis of 2.4-4.1% per patient year. Only one patient had a Melody valve stent fracture. The authors concluded the “folded Melody valve” technique did not appear to affect the valve’s performance during mid-term follow-up with no significant progression in valve gradient or pulmonary insufficiency and low incidence of valve re-interventions and infective endocarditis. While the approval of the 23 mm Sapien valve, which has a length of 14.3 mm, may prevent the need for this technique in some patients, it is still applicable in many patients with smaller diameter conduits or bioprosthetic valve which won’t accommodate a 23 mm diameter valve.   

All editors: Gary E. Stapleton, MD, FSCAI