HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Abstract Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): Mirko Doss Sven Martens Jeffrey P. Wood Gerhard Wimmer-Greinecker Anton Moritz Permission Requests Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Doss, M. Articles by Moritz, A. Search for Related Content PubMed PubMed Citation Articles by Doss, M. Articles by Moritz, A. Related Collections Valve disease

Ann Thorac Surg 2005;79:682-685
© 2005 The Society of Thoracic Surgeons

---

New technology

Aortic Leaflet Replacement With the New 3F Stentless Aortic Bioprosthesis

^a Department of Thoracic and Cardiovascular Surgery, Johann Wolfgang Goethe University, Frankfurt/Main, Germany

Accepted for publication October 28, 2003.

^* Address reprint requests to Dr Doss, Department of Thoracic and Cardiovascular Surgery, Johann Wolfgang Goethe-University Frankfurt/Main, Theodor-Stern-Kai 7, Frankfurt/Main 60590, Germany
mirkodoss{at}aol.com

	Abstract

Top Abstract Introduction Technology Technique Clinical Experience Comment Disclosures and Freedom of... Footnotes References

 
PURPOSE: Clinical trials with the new 3F stentless aortic bioprosthesis began October 2001, and as one of the first centers to implant this prosthesis in humans, we would like to present our experiences with this new device.

DESCRIPTION: The 3F aortic bioprosthesis is a stentless biological heart valve fabricated from three equal leaflets of equine pericardium, assembled in a tubular shape, and implanted in the native aortic root to replace the patient's diseased aortic leaflets. Between January 2002 and August 2002, 24 3F aortic bioprostheses were implanted at our institution. Effective orifice area, mean gradients, and ejection fraction were evaluated by echocardiography at discharge and at 12-month follow-ups after surgery.

EVALUATION: At 12-month follow-ups, the 3F bioprosthesis showed a good hemodynamic performance with a significant drop of mean gradients to 10.3 mm Hg, a mean effective orifice area of 1.7 cm², and a mean ejection fraction of 61.5%.

CONCLUSIONS: The clinical performance of the new 3F aortic bioprosthesis is comparable with regular stentless aortic valves. However its unique design facilitates implantation.

	Introduction

Top Abstract Introduction Technology Technique Clinical Experience Comment Disclosures and Freedom of... Footnotes References

 
In an effort to improve the outcomes of patients after aortic valve replacement with stented bioprosthesis, stentless valves were introduced to clinical practice in the early 1990s. These valves were designed to be less obstructive and thus result in lower transvalvular gradients that would in turn cause faster and more complete regression of left ventricular hypertrophy.

However, the implantation technique of stentless valves is more complex and demanding on the surgeon with prolonged cross-clamp and bypass times. In view of severe left ventricular hypertrophy in patients with aortic stenosis and associated difficulties in myocardial protection, there is a resurgence of interest in designing a stentless valve that is easier and quicker to implant. A recent development in this field includes the new 3F aortic bioprosthesis (3F Therapeutics, Lake Forest, CA), and we report our initial evaluation and clinical experience with this valve substitute.

	Technology

Top Abstract Introduction Technology Technique Clinical Experience Comment Disclosures and Freedom of... Footnotes References

 
The 3F stentless pericardial bioprosthesis consists of a tubular structure assembled from three equal sections of equine pericardial tissue, fixed with low concentration glutaraldehyde. The tubular design was chosen with consideration that during the development of human heart valves in utero, the primal structure is tubular in shape, but adopts the form found when fully developed due to blood flow through the heart during its function.

The three equal leaflets of pericardial tissue have been assembled together with locking sutures. A total of three equally spaced tabs of special design that have been placed at the outflow, simulating commissures that allow fixation in the vicinity of the sinotubular junction.

At the inflow area of the tubular structure, a slightly scalloped polyester ring has been incorporated to allow easy suturing to the bottom of the aortic sinus, thus securing and minimizing the potential for perivalvular leakage.

The concept of a surrounding aortic wall, stabilizing the prosthesis, has been abandoned. Thus, only aortic leaflets are implanted into the native aorta.

	Technique

Top Abstract Introduction Technology Technique Clinical Experience Comment Disclosures and Freedom of... Footnotes References

 
In this initial experience, the 3F stentless aortic bioprosthesis was used to replace the patient's native aortic valve, due to isolated aortic valve stenosis or mixed aortic valve disease.

Surgical Implantation
Using our standard technique of cardiopulmonary bypass and cardioplegic arrest, access to the aortic valve was gained through a transverse aortotomy. Special care was taken to stay well above the sinotubular junction, as the commissural posts of the prosthesis are attached in its close proximity. A transverse aortotomy is chosen instead of the hockey stick incision so that the geometry of the sinuses is not disturbed, thus allowing for exact orientation of the leaflets. Then the aortic valve is inspected. It is important at this point to assess whether the commissures are evenly located at 120° apart or if one sinus is proportionally larger than the others. This needs to be reassessed later when the prosthesis is implanted. Attention is also paid to the coronary ostium abnormalities, calcifications of the aortic wall, and mismatches between the annulus and sinotubular junction.

After excision of the native aortic valve and debridement of the aortic annulus, the surgeon accurately sizes the aortic annulus using seizers especially designed for the 3F valve. In the event that the diameter of the annulus is between two valve sizes (ie, 21 mm to 23 mm), the smaller size is chosen. This decision is based on the experiences of the in vitro tests, at which time it became evident that in the previously described scenario the small valve will display a superior hemodynamic performance. This proceeding also eliminates the possibility of stuffing a larger valve inside a fixed aortic annulus, thereby producing some obstruction or altering the geometry of the prosthesis at the time of implantation. If there were apparent mismatches in size between the annulus and the sinotubular junction, the patient was excluded from the study. The prosthesis requires rinsing in saline solution three times for 2 minutes each time. During this time, three 4-0 propylene sutures are placed approximately 120° apart in the subannular position corresponding to the three commissures. The sutures are then passed through the sewing ring of the valve below the position of the commissural posts. Using the handle, the valve is then lowered into place in the annulus. The handle is then removed, and the prosthesis is inverted into the ventricle. Using the three 4-0 propylene sutures, the valve is implanted with continuous running sutures with three interruptions at 120°. Initially we made sure to stay in a horizontal subannular plain. With time we learned that we can achieve better hemodynamic performance of the valve if we implant it in a somewhat supraannular position (Fig 1). At the interruptions, the sutures are passed outside the native aorta when possible and tied there to avoid irritation of the leaflets by the knots. The valve is then everted back into the aorta. Then the commissural tabs are attached to the aorta by three single 4-0 cardionyl sutures (Cardionyl; Péters Laboratories, Bobigny-Cedex, France) (Fig 2). Thus, there is no need for a second line of running sutures to attach the rims of the valve to the native aorta at the outflow side of the prosthesis.

View larger version (13K): [in this window] [in a new window]   Fig 1. Position of the proximal suture line in the stentless 3F aortic bioprosthesis. (LCO = left coronary ostium; RCO = right coronary ostium.)

View larger version (114K): [in this window] [in a new window]   Fig 2. Intraoperative view of the stentless 3F aortic bioprosthesis.

Assessment of Aortic Valve Function
Prosthesis function was assessed intraoperatively by transesophageal echocardiography (Fig 3). Special attention was focused on the motion of the leaflets, positioning of the commissural posts, geometry of the valve, transvalvular gradients, and regurgitation, as well as effective orifice area.

View larger version (157K): [in this window] [in a new window]   Fig 3. Intraoperative transesophageal echocardiography showing wide open leaflets of the 3F bioprosthesis in the aortic root.

Further transthoracic echocardiography examinations were carried out at discharge, at 6 months, and at 12-month follow-up after surgery.

	Clinical Experience

Top Abstract Introduction Technology Technique Clinical Experience Comment Disclosures and Freedom of... Footnotes References

 
From January 2002 through August 2002, the 3F stentless aortic bioprosthesis was implanted in 24 patients to treat their isolated aortic valve disease as a part of a multicenter United States Food and Drug Administration trial. The mean age of the patients was 71.5 ± 4.8 years. All patients gave written informed consent before inclusion in the study. The consent form and the study protocol were approved by our ethical committee. The study was sponsored by 3F Therapeutics (Lake Forest, CA). None of the investigators or patients received payments to participate in this study.

All patients requiring isolated aortic valve replacement with or without concomitant procedures, except other valve replacements, greater than 20 years of age, who were eligible for an aortic bioprosthesis were included in the study. Most patients had aortic valve stenosis, and some patients had mixed aortic valve disease. Eight patients were excluded intraoperatively from receiving a 3F valve. The reasons for exclusion were abnormal origin of coronary arteries, calcified aortic root, and mismatch between the aortic annulus and sinotubular junction due to dilatation of the ascending aorta. Patients with active endocarditis and bicuspid aortic valves were not included in this initial study. The prosthesis proved to be versatile and well-suited to replace the native aortic valve of patients with aortic valve disease. It showed good handling characteristics with its equine tissue being very flexible and allowing inversion into the ventricle. As only the inflow side of the prosthesis needs a continuous running suture, it is easier and quicker to implant than conventional stentless valves. This is reflected in the mean cross-clamp time of 73.8 ± 17.2 minutes. At 12-month follow-ups, the 3F prosthesis showed good hemodynamic performance with a significant drop in transvalvular gradients to 10.3 mm Hg, a mean effective orifice area of 1.7 cm², and a mean ejection fraction of 61.5%. The echocardiographic data are summarized in Table 1.

	Comment

Top Abstract Introduction Technology Technique Clinical Experience Comment Disclosures and Freedom of... Footnotes References

 
This article describes our initial evaluation and application of the new 3F stentless aortic bioprosthesis in patients with aortic valve stenosis.

Its unique design, based on the concept that form follows function, constitutes a step toward a stentless valve that is easier and quicker to implant than conventional stentless valves, while providing the same favorable hemodynamic characteristics. The concept of replacing only the aortic leaflets has a number of advantages over conventional stentless valves. In porcine stentless valves, certain structural features have been identified to result in elevated transvalvular gradients; these are the muscular shelf below the right coronary ostium and hematoma formation between the outer wall of the prosthesis in the native aortic sinus [1–3]. In the 3F prosthesis, the surgeon does not need to consider and adapt his implantation technique to these features.

Furthermore, porcine stentless valves require two circumferential suture lines, one at the inflow and one at the outflow side [3, 4]. In our experience with the 3F valve, the advantage of only needing one circumferential suture line at the inflow side saves time and makes the implantation easier for the surgeon.

In this study the 3F prosthesis showed hemodynamic characteristics that are comparable with conventional stentless valves [3, 4]. We demonstrated that the altered implantation and its design have no negative effect on the performance of the valve. From our investigators' meetings, we are aware that other centers implanting the 3F valves have observed lower transvalvular gradients, due in part to the greater valve sizes. In the pre-clinical animal studies, Müller and colleagues' [5] reported transvalvular gradients of 3.3 mm Hg to 7.9 mm Hg. These results were presented at the 2002 American Association for Thoracic Surgery Annual Meeting [5].

The commissural tabs of the 3F prosthesis are attached to the native aorta in close proximity to the sinotubular junction. The prosthesis is designed to be tubular in shape and therefore the leaflets are longer than the native semilunar leaflets of the aorta. The choice to make the leaflets this long was to ensure that a good coaptation surface was created in diastole. This is an important feature because it is known that conventional stentless valves have an incidence of leakage of 2% to 4% in the first year, rising to 14% to 30% by the 8th postoperative year [6, 7].

In this study, we report our initial experience with the 3F stentless aortic bioprosthesis. This device is well suited to treat a diverse patient population requiring aortic valve replacement. In the course of the study, we have modified our implantation technique, which when meticulously carried out provides good hemodynamic results. However, different teams have achieved excellent results using alternative implantation methods with the 3F prosthesis.

Despite encouraging short-term results, we need data documenting long-term performance and durability of this new valve. Additional experience and close patient follow-up will be necessary to determine the late success rate of this device.

	Disclosures and Freedom of Investigation

Top Abstract Introduction Technology Technique Clinical Experience Comment Disclosures and Freedom of... Footnotes References

 
The tested 3F Aortic Bioprostheses were donated to our department by 3F Therapeutics (Lake Forest, CA). Additionally, the sum of $20,000 was provided by the company to compensate for the expenses associated with the follow-up of the patients. The authors had full control of the design of the study, methods used, outcome parameters, analysis of data, and production of the written report.

	Footnotes

Top Abstract Introduction Technology Technique Clinical Experience Comment Disclosures and Freedom of... Footnotes References

 
The Society of Thoracic Surgeons, the Southern Thoracic Surgical Association, and The Annals of Thoracic Surgery neither endorse nor discourage use of the new technology described in this article.

	References

Top Abstract Introduction Technology Technique Clinical Experience Comment Disclosures and Freedom of... Footnotes References

 

1. Takami Y, Ina H. Resolution of perivalvular hematoma of the Freestyle stentless aortic bioprosthesis implanted with a subcoronary techniques. Jpn J Thorac Cardiovasc Surg. 2001;49(11):675–678[Medline]
2. Kirsch M, Vermes F, Houel R, Loisance D. The freestyle stentless aortic bioprosthesis: more about the subcoronary technique. Eur J Cardiovasc Surg. 2001;19:369–371
3. Cohen G, Christakis GT, Joyner CD, et al. Are stentless valves hemodynamically superior to stented valves? A prospective randomized trial. Ann Thorac Surg. 2002;73:767–775[Abstract/Free Full Text]
4. Doss M, Martens S, Wood JP, et al. Performance of stentless versus stented aortic valve bioprostheses in the elderly patientsa prospective randomized trial. Eur J Cardiothorac Surg. 2003;23:299–304[Abstract/Free Full Text]
5. Müller XM, von Segesser LK. A new equine pericardial stentless valve. J Thorac Cardiovasc Surg 2003;125:1405–11.
6. Jin XY, Ratnaturga C, Pillai R. Performance of Edwards Prima stentless aortic valve over eight years. Semin Thorac Cardiovasc Surg. 2001;13:165–167
7. David TE, Ivanov J, Eriksson MJ, Bos J, Feindel CM, Rokowski H. Dilatation of the sinotubular junction causes aortic insufficiency after aortic valve replacement with the Toronto SPV bioprosthesis. J Thorac Cardiovasc Surg. 2001;122:929–934[Abstract/Free Full Text]

This article has been cited by other articles:

				S. Martens, A. Ploss, S. Sirat, A. Miskovic, A. Moritz, and M. Doss Sutureless Aortic Valve Replacement With the 3f Enable Aortic Bioprosthesis. Ann. Thorac. Surg., June 1, 2009; 87(6): 1914 - 1917. [Abstract] [Full Text] [PDF]

				W. A. Goetz, T. E. Tan, K. H. Lim, S. L. H. Salgues, N. Grousson, F. Xiong, Y. L. Chua, and J. H. Yeo Truly stentless molded autologous pericardial aortic valve prosthesis with single point attached commissures in a sheep model Eur. J. Cardiothorac. Surg., April 1, 2008; 33(4): 548 - 553. [Abstract] [Full Text] [PDF]

				P. Stelzer Stentless Aortic Valve Replacement: Porcine and Pericardial Card. Surg. Adult, January 1, 2008; 3(2008): 915 - 934. [Full Text]

				D. Grandmougin and G. Fayad Implantation of a modified freestyle valve with a single inflow suture line: technical patterns and advantages. Ann. Thorac. Surg., September 1, 2006; 82(3): 1128 - 1130. [Abstract] [Full Text] [PDF]

				W. A. Goetz, K. H. Lim, R. Ibled, N. Grousson, S. L. H. Salgues, and J. H. Yeo Forces at single point attached commissures (SPAC) in pericardial aortic valve prosthesis Eur. J. Cardiothorac. Surg., February 1, 2006; 29(2): 150 - 155. [Abstract] [Full Text] [PDF]

This Article Abstract Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): Mirko Doss Sven Martens Jeffrey P. Wood Gerhard Wimmer-Greinecker Anton Moritz Permission Requests Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Doss, M. Articles by Moritz, A. Search for Related Content PubMed PubMed Citation Articles by Doss, M. Articles by Moritz, A. Related Collections Valve disease