Asian Cardiovasc Thorac Ann 2008;16:515-516
© 2008 Asia Publishing EXchange Ltd
PEDIATRIC MITRAL VALVE REPAIR WITH THE NOVEL ANNULOPLASTY RING: KALANGOS-BIORING®
Mustafa Cikirikcioglu, MD,
Erman Pektok, MD,
Patrick O Myers, MD,
Jan T Christenson, MD,
Afksendiyos Kalangos, MD
Department of Cardiovascular Surgery, University Hospital of Geneva, 24, Rue Micheli-du-Crest 1211, Geneva, Switzerland, Tel: 41 22 372 76 63, Fax: 41 22 372 76 34, E-mail: mustafa.cikirikcioglu{at}hcuge.ch
Dear Editor,
We read with great interest the article of Reddy and colleagues1 and congratulate them for their valve repair oriented efforts in this very important and challenging patient group. They used three surgical techniques for pediatric mitral repair: (i) modified De Vega annuloplasty with pledgets on the annulus, (ii) commissural closure on both commissures and (iii) shortening of elongated chordae. They concluded that "valve repair can be performed without annuloplasty rings". Although we understand their concern, we do not agree with this conclusion.
Pediatric valve repair with or without a supra-annular annuloplasty ring is a double edged sword. On the one hand, supporting the repaired mitral valve with an annuloplasty ring is essential for a long-lasting result.2 Although most authors agree on the necessity of the implantation of an annuloplasty ring for adult patients; pediatric mitral valve repair with the conventional annuloplasty rings are disputatious, because they can create iatrogenic mitral stenosis as the child grows without proportional growth of the mitral annulus. Additionally, most children with rheumatic mitral disease require smaller annuloplasty rings, especially when one keeps in mind that these patients usually are one to two standard deviations below the normal size for their age from cardiac cachexia.3 This makes it two times harder to use a conventional annuloplasty ring, because the smallest size of those is 24 mm. On the other hand, implantation of a supra-annular ring, or surrogates such as Teflon pledgets for modified De Vega annuloplasty, can induce a strong fibrotic reaction, especially in children. The progression of this fibrosis toward the leaflets may decrease leaflet flexibility and make secondary valve repair impossible4 (Figure 1
).
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Figure 1. Operative images 4 years after mitral repair using Carpentier-Edwards ring. Massive fibrotic reaction around the supra-annular ring was progressing toward leaflets (arrows).
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A unique atrio-venticular annuloplasty ring for children is Kalangos-Bioring®, which is available in sizes down to 16 mm (see Figure 2). Kalangos-Bioring® is a partial ring made of 1,4-polydioxanone that is implanted directly into the valve annulus. It is degraded by hydrolysis, and elicits a subendocardial fibrous reaction for durable remodeling of the annulus.5 Our pediatric mitral valve repair cohort using this biodegradable mitral annuloplasty ring has now reached 90 patients, with a mean follow-up of 27.3 ± 17.2 (1.8–60.5) months. Eighty-three patients showed favorable outcome without significant failure. Seven patients have required reoperation within 1 to 20 months for mitral valve re-repair (n = 1) or replacement (n = 6) because of rheumatic (n = 4), congenital (n = 2) and degenerative (n = 1) mitral valve lesions.
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Figure 2. Kalangos-Bioring®. This ring is implanted subendocardially into the annulus using the needles attached at both ends and pulling up the suture respecting the exit axis5.
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We recently published our results of 220 children who underwent mitral valve repair for rheumatic valvular disease4, 173 of which received a Carpentier-Edwards® ring and 40 a Kalangos-Bioring®. Overall mitral valve related event-free survival was 95.1% at 5 years and 93.2% at 10 years. The mean trans-mitral gradient was 5.2 ± 1.9, 6.2 ± 2.0 and 7.0 ± 2.3 mm Hg for Carpentier-Edwards® ring, and 2.8 ± 0.5, 3.1 ± 0.7 and 3.3 ± 0.5 mm Hg for Kalangos-Bioring® at 7 days, 6 months and 1 year postoperatively (p < 0.001 for all time points). Mean gradient remained unchanged during the 1st year in 65% (26/40) of the Kalangos-Bioring®, and in 20% (31/147) of the Carpentier-Edwards® ring (p < 0.001). Because of the ease of implantation of the Kalangos-Bioring®, our aortic cross clamp and cardiopulmonary bypass times are reduced by 10 min compared to those of our Carpentier-Edwards ring implantations.
We believe that an annuloplasty ring is crucial for successful and durable mitral valve repair. Avoidance of pledget use by using a subendocardially implanted biodegradable annuloplasty ring may prolong the time-to-reoperation period (even life-long for a group of patients), and make the second operation as re-repair possible by preventing the excess fibrous tissue formation on the annulus and leaflets. Thus, Kalangos-Bioring® provides more flexibility and chance to the surgeon for a complete pediatric mitral valve repair.
REFERENCES
- Reddy PK, Dharmapuram AK, Swain SK, Ramdoss N, Raghavan SS, Murthy KS. Valve repair in rheumatic heart disease in pediatric age group. Asian Cardiovasc Thorac Ann 108;16:129–33.
- Cohn LH, Couper GS, Aranki SF, Rizzo RJ, Kinchla NM, Collins JJ Jr. Long-term results of mitral valve reconstruction for regurgitation of the myxomatous mitral valve. J Thorac Cardiovasc Surg 1994;107:143.[Abstract/Free Full Text]
- Kalangos A, Christenson JT, Beghetti M, Cikirikcioglu M, Kamentsidis D, Aggoun Y. Mitral valve repair for rheumatic valve disease in children – long-term results and impact of the use of a biodegradable mitral ring. Ann Thorac Surg 2008;86(1):161–9.[Abstract/Free Full Text]
- Tanaka K, Makuuchi H, Naruse Y, Kobayashi T, Hayashi I, Takayama T, et al. Mitral stenosis due to fibrous tissue overgrowth after mitral valve repair. J Cardiovasc Surg (Torino) 2003;44:59–60.[Medline]
- Kalangos A, Sierra J, Vala D, Cikirikcioglu M, Walpoth B, Orrit X, et al. Annuloplasty for valve repair with a new biodegradable ring: An experimental study. Journal of Heart Valve Disease 2006;15:783–90.[Medline]
