Unusual 25-Year Durability of anIonescu-Shiley PericardialBioprosthesisAntonio Fiore, MD, Denton A. Cooley, MD,Antonino M. Grande, MD, Mario Viganò, MD,and Paolo Angelini, MD

Department of Cardiac Surgery, Fondazione IRCCS Policlinico“San Matteo,” Pavia, Italy; Division of Cardiovascular Surgeryand Department of Cardiology, Texas Heart Institute, St.Luke’s Episcopal Hospital, Houston, Texas

Ionescu-Shiley valve was withdrawn from clinical use in1987 for its early structural failure after implantation.This was due to valve design rather than the naturalproperties of bovine pericardium itself. We describe theunexpected 25-year survival of an Ionescu-Shiley bio-prosthesis in the mitral and tricuspid positions, im-planted to treat endomyocardial fibrosis. This reportmakes 2 important points: (1) pannus overgrowth may bea favorable determinant of the durability of xenografts,and (2) bovine pericardial valves may have excellenthemodynamic performance and tissue durability formore than 20 years in the mitral position even in youngpatients.

(Ann Thorac Surg 2011;91:e52–3)© 2011 by The Society of Thoracic Surgeons

The main drawback of biologic valves is their limiteddurability due to progressive structural valve dete-

rioration, and few such valves function beyond 20 yearsafter the implant. The Ionescu-Shiley valve (Shiley, Inc,Irvine, CA) was introduced in 1976, and it was the firstcommercially available pericardial valve, which waswidely used because of excellent early hemodynamicsperformance [1]. Due to progressive structural deteriora-tion in the first years after implantation, these xenografts(standard and low-profile types) were withdrawn fromclinical use in the late 1980s.

Many reports hinted that the shortened durability ofIonescu-Shiley bioprosthesis was mainly a consequenceof a primary tissue failure. The typical reported mode offailure is leaflets tear occurring at the site of tissueattachment to commissural stent posts with extensionto the depth of the cusps [2, 3]. In addition, the cusptear is more likely to occur in the mitral rather thanaortic position, because of increased mechanical stressdue to higher closing pressure. Despite the use of adifferent technique to affix the valve leaflets to thestents in the low-profile valve, the problem of cusptearing persisted [2].

A 39-year-old Italian woman was admitted in 1982 to theTexas Heart Institute in Houston, Texas, with the diag-nosis of obliterative restrictive endomyocardial fibrosiswith involvement of the right and left ventricle, thepapillary muscles, and chordae tendinae of both mitraland tricuspid valves, causing moderate mitral regurgita-tion. The patient underwent surgical repair, involving an

Accepted for publication Nov 9, 2010.

Address correspondence to Dr Fiore, Department of Cardiac Surgery,

Fondazione IRCCS Policlinico “San Matteo,” Piazzale Golgi 2, Pavia,27100 Italy; e-mail: fioreant7@gmail.com.

© 2011 by The Society of Thoracic SurgeonsPublished by Elsevier Inc

extensive endocardial decortication and a mitral andtricuspid prosthetic valve replacement. The valves werereplaced using Ionescu-Shiley prosthetic valves (a 25 mmfor the mitral valve and a 27 mm for the tricuspid valve).

The patient did well for 23 years, until 2005, when shehad shortness of breath develop on exertion and echo-cardiographic evidence of degeneration of the mitralprosthesis, with regurgitation.

In 2007, the patient’s dyspnea progressed to functionalclass III, and transthoracic and transesophageal echocar-diography evidenced structural failure of both xeno-grafts, calcifications, and severe stenosis of the tricuspidbioprosthesis and moderate regurgitation of the mitralbioprosthesis. At this time, the left ventricular end-diastolic and end-systolic volume was 90 mL and 34 mL,respectively, and the left ventricular ejection fraction was64%. The patient underwent new surgery, in November2007, at the Division of Cardiac Surgery of the Universityof Pavia for redo tricuspid and mitral valve replacement.The tricuspid xenograft was replaced with a 25-mmCarpentier-Edwards biologic valve (Edwards Life-sciences Inc, Irvine, CA), and the mitral xenograft wasreplaced with a 27-mm St. Jude Medical bileaflet me-chanical valve (St. Jude Medical Inc, Minneapolis, MN),while using a minimally invasive right thoracotomy ap-proach (port-access surgery).

Intraoperatively, the Ionescu-Shiley tricuspid valveshowed severe calcifications of the three cusps withreduced excursion of the leaflets and annular pannusproliferation. The mitral prosthesis showed milder calci-fication of the leaflets, but thick pannus overgrowthcompletely covered the annular ring and the posts (Fig 1).Only one tear at the commissural alignment stitch wasobserved on this xenograft. Two large tears were ob-served at the tricuspid xenograft in the proximity of thesevere calcifications.

At her 2-year follow-up, the patient was in goodcardiovascular conditions (New York Heart Associationfunctional class II), while her echocardiography demon-strated good function of the prosthetic valves and normalleft and right ventricular function.

Comment

Endomyocardial fibrosis is a rare pathology and its causeand pathogenesis still remains obscure. This disease ischaracterized by formation of fibrous tissue on the endo-cardium, and the myocardium of the right or left (or both)ventricle apices and inflow tracts. Involvement of thepapillary muscles and chordae tendinae is frequent andtheir tethering may cause progressive mitral or tricuspidregurgitation, or both [4].

The prognosis is very poor in endomyocardial fibrosispatients, and medical treatment is often unsatisfactory.The only satisfactory option is performing the completeendomyocardial decortication and atrioventricular valvereplacement or repair, depending on the level of involve-ment of the valve apparatus [5].

Structural valve deterioration is the most commoncause of reoperation after bio-prosthetic replacement,and only few such valves remain functional beyond 20years after implantation.

Patient-related and valve-related factors may influence

the durability of xenografts. The rate of structural valve

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e53Ann Thorac Surg CASE REPORT FIORE ET AL2011;91:e52–3 25-YEAR DURABILITY OF IONESCU-SHILEY

deterioration is age-related and this increased in youngerpatients due to a high rate of early calcification. Theintrinsic durability of a biologic xenograft is related tovalve design, mechanical properties, and the preparationof the biologic tissue.

Early failure of the first-generation pericardial valves wasconsidered to be related to valve design rather than fromthe bio-properties of bovine pericardial tissue itself [6].

ith appropriate changes in stent design and tissue pres-rvation, the pericardium was reintroduced in the manu-acturing of valve prosthesis, leading to better hemody-amic performance and a lower rate of structural valveeterioration than second-generation porcine valves.The Ionescu-Shiley valve was the first available pericar-

ial valve thatj was withdrawn from clinical use in 1987ecause of its high incidence of early leaflets tear, which

ends to occur at the site of tissue attachment to commis-ural stent posts in the first 2 to 6 years after implantation [2,

7]. Masters and colleagues [2] showed progressive deterio-ration of the Ionescu-Shiley valve beyond 10 years with anactuarial freedom from reoperation at 13 years of 25% � 9%for mitral valve replacement [2].

In the present report, we described exceptional dura-bility of Ionescu-Shiley bioprosthesis in the mitral andtricuspid positions. Although several patient-related andvalve-related factors may influence the durability of axenograft, the reason or reasons for this unexpectedlongevity of the xenografts is not easily explained, but asButany and colleagues [8] also suggested, pannus over-growth that is usually considered a cause of prostheticdysfunction could be an important factor of the durabilityof xenografts. The pannus was abundant and it coveredthe stent and the posts, possibly contributing to bothprotection from excessive calcification and increasing

mechanical resistance to stress.

In addition, the present report illustrates recoveredand preserved left ventricular function during 25 years inthe presence of inflammatory cardiomyopathy that evi-dently became spontaneously dormant.

I would like to thank and express my sincere gratitude toProfessor Angelini and Professor Cooley for their preciouscollaboration and guidance.

References

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3. Hilbert SL, Ferrans VJ, McAllister HA, Cooley DA. Ionescu-Shiley bovine pericardial bioprostheses. Histologic and ultra-structural studies. Am J Pathol 1992;140:1195–204.

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7. Kobayashi Y, Nagata S, Eishi K, Nakano K, Miyatake K. SerialDoppler echocardiographic evaluation of Carpentier-Edwards pericardial valve dysfunction: comparison withIonescu-Shiley valve. Am Heart J 1998;135:1086–92.

8. Butany JW, Kesarwani R, Yau TM et al. The role of pannus in

Fig 1. Ventricular view of the ex-cised Ionescu-Shiley prosthesis. (A)Mitral xenograft and (B) tricuspidxenograft.

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