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Ann Thorac Surg 2001;71:609-613
© 2001 The Society of Thoracic Surgeons

Original article: cardiovascular

Hemodynamic evaluation of 19-mm Carpentier-Edwards pericardial bioprosthesis in aortic position

Hiromitsu Takakura, MDa, Tatsuumi Sasaki, MDa, Kazuhiro Hashimoto, MDa, Takashi Hachiya, MDa, Katsuhisa Onoguchi, MDa, Motohiro Oshiumi, MDa, Shigeyuki Takeuchi, MDa

a Department of Cardiovascular Surgery, Saitama Cardiovascular and Respiratory Center, Saitama, Japan

Accepted for publication July 15, 2000.

Address reprint requests to Dr Takakura, 1696 Itai, Konan-machi, Osato-gun, Saitama 360-0105, Japan
e-mail: idabagus{at}yj8.so-net.ne.jp


   Abstract
Top
 Abstract
Introduction
 Material and methods
 Results
 Comment
 Acknowledgments
 References
 
Background. The aortic Carpentier-Edwards pericardial bioprosthesis offers good long-term clinical outcomes with a low rate of structural deterioration. However, little in vivo hemodynamic data is available for this bioprosthesis.

Methods. To determine the hemodynamic performance of the 19-mm Carpentier-Edwards pericardial valve, both cardiac catheterization and dobutamine stress echocardiography were electively performed in 10 patients. The mean age at the study was 71.6 ± 4.4 years and the mean body surface area was 1.39 ± 0.11 m2. The peak-to-peak gradient, instantaneous peak gradient, mean gradient, and valve orifice area were measured by standard cardiac catheterization. The Doppler-derived gradients and valve orifice area were also measured both at rest and during dobutamine infusion.

Results. The average peak-to-peak gradient, instantaneous peak gradient, mean gradient, and valve orifice area measured by catheterization were 13.0 ± 5.4 mmHg, 28.5 ± 7.7 mmHg, 12.0 ± 4.9 mmHg, and 1.55 ± 0.45 cm2, respectively. The peak and mean Doppler gradients, and valve orifice area by resting echocardiography were 27.7 ± 9.5 mmHg, 12.3 ± 4.8 mmHg, and 1.39 ± 0.26 cm2, respectively. At a dosage of 10 µg/kg/min of dobutamine, the mean Doppler gradient rose mildly to 22.2 ± 4.8 mmHg, while the cardiac output increased from 4.49 ± 0.44 to 6.64 ± 0.87 L/min. The valve orifice area during the 10 µg/kg/min dobutamine infusion (1.55 ± 0.25 cm2) was significantly larger than its value at rest (p < 0.05).

Conclusions. With acceptable hemodynamic performance, use of the aortic 19-mm Carpentier-Edwards pericardial valve is a reliable option for elderly patients with a small annulus.


   Introduction
Top
 Abstract
 Introduction
Material and methods
 Results
 Comment
 Acknowledgments
 References
 
Appropriate procedures and prostheses for aortic valve replacements in patients with a narrow aortic annulus should be decided by taking into account the patient characteristics, the hemodynamic performance of the prostheses, and valve durability. Although the first generation of bovine pericardial valves provided excellent hemodynamic performance, even in small size [1], these valves were withdrawn from the market because of an unacceptably high rate of structural deterioration [2]. The aortic Carpentier-Edwards pericardial bioprosthesis (model 2900; Baxter Healthcare Corp., Santa Ana, CA), one of the latest generation of bovine pericardial valves, was then introduced internationally in 1980 and in our country in 1985. According to previous reports, this bioprosthesis provides a superior in vitro hemodynamic performance to both the older generation of pericardial valves and porcine bioprostheses [3]. Furthermore, the durability of this valve in the aortic position is considered to be acceptable, particularly in elderly patients [4, 5]. Consequently, we have been using the aortic Carpentier-Edwards pericardial valve in elderly patients since 1996. Recently, long-term clinical outcomes and hemodynamic data by resting echocardiograms have been published for the 19-mm bioprosthesis [6, 7]. However, little hemodynamic data by direct measurement or stress echocardiography is available. This report documents the hemodynamic performance of the 19-mm Carpentier-Edwards pericardial valve by standard cardiac catheterization and dobutamine stress echocardiography.


   Material and methods
Top
 Abstract
 Introduction
 Material and methods
Results
 Comment
 Acknowledgments
 References
 
Patient selection
From July 1996 to January 2000, 30 patients underwent aortic valve replacements with the Carpentier-Edwards pericardial bioprosthesis at our institution without operative death. Eleven (36.7%) of the patients received the 19-mm bioprosthesis. The main indication for aortic valve replacement was degenerative calcified stenosis in 8 patients, rheumatic changes in 2, and a congenital bicuspid valve with calcified stenosis in 1. Concomitant surgical procedures included coronary artery bypass graftings in 4 patients and a patch enlargement of a narrow aortic root in 1.

In 10 of the 11 patients, both cardiac catheterization and dobutamine stress echocardiography were electively performed 9.8 ± 10.5 months (ranged from 1 to 34 months) after the insertion of the bioprosthesis. The patients with concomitant coronary artery bypass underwent a hemodynamic assessment at the time of coronary angiography, 1 month after the operation. The assessments for other patients were carried out at median of 15.7 months after surgery. There were 1 male and 9 female patients; the mean age at the study was 71.6 ± 4.4 years (ranged from 65 to 78 years), and the mean body surface area was 1.39 ± 0.11 m2 (ranged from 1.18 to 1.53 m2). All patients had neither episodes of postoperative myocardial infarction nor symptoms of myocardial ischemia, and were in regular sinus rhythm and in New York Heart Association class I or II at the time of study. One patient associated with mild mitral stenosis and atrial fibrillation was excluded from this study. The study was approved by the Institutional Review Board at Saitama Cardiovascular and Respiratory Center, and informed consent was obtained from each patient before inclusion in this study.

Cardiac catheterization
Cardiac catheterization was performed under mild sedation (diazepam) and local anesthesia (lidocaine). Right heart catheterization was performed with a balloon-tipped thermodilution catheter. Central venous, pulmonary artery, and pulmonary capillary wedge pressures were measured in routine technique, and cardiac output was obtained in the thermodilution technique by averaging the values of three measurements. Left heart catheterization was performed with a 5F multipurpose fluid-filled catheter through a 6F long sheath catheter inserted from the right femoral artery. Left ventricular pressure was measured by crossing the bioprosthesis, and descending aortic pressure was obtained with the sheath catheter to measure simultaneous transvalvular gradients. Before the tip of the catheter crossed the valve, the descending aortic pressure was calibrated to a zero gradient using the ascending aortic pressure. An on-board 12-channel recorder of the CATHCOR (version 3.3) computer-assisted recording and monitoring system (Siemens-Elema AB, Solna, Sweden) was used for pressure waveforms recording at a paper speed of 100 mm/sec. The systolic mean pressure gradient across the prosthesis, left ventricular aortic peak-to-peak pressure gradient, and left ventricular end-diastolic pressure were digitized with the on-board image analysis computer of the CATHCOR system. Instantaneous pressure gradients were analyzed at 10-msec intervals using the simultaneously recorded waveforms for the left ventricular and aortic pressures, and the maximum value of these measurements was then used as the peak pressure gradient. Each set of pressure data was obtained by measuring consecutive five beats and taking the average of the five measurements.

Valve orifice area (VOA) was calculated by the Gorlin and Gorlin formula [8]: VOA = F/(44.3 {surd}MPG), F = CO/(HR · ET), where F is mean transvalvular flow rate in systole (ml/sec), MPG is the mean pressure gradient, CO is cardiac output (ml/min), HR is heart rate (beats/min), and ET is ejection time (sec/beat). After obtaining those hemodynamic data, coronary angiography was performed according to the standard technique.

Dobutamine stress echocardiography
All echocardiograms were examined by a same expert echocardiographer, using a Hewlett-Packard Sonos 5500 apparatus (Hewlett-Packard Co., Andover, MA) with a 2.0- to 4.0-MHz ultra-band image transducer (Hewlett-Packard 21330A). All echocardiograms were recorded with a strip-chart recorder (Hewlett-Packard 77510A) for subsequent analysis.

At rest, an M-mode echocardiogram of the left ventricle was recorded using the left parasternal short-axis view, and cardiac output was calculated as a product of stroke volume (SV) and heart rate, using the formula of Teichholtz and co-workers [9]: Volume (ml) = 7/(2.4 + D) · D3, CO (ml/min) = SV · HR = (EDV-ESV) · HR, where D is dimension of the left ventricular chamber, EDV is end-diastolic volume, and ESV is end-systolic volume. Left ventricular ejection fraction (LVEF) was calculated as follows: LVEF = SV/EDV.

Flow velocity across the prosthesis (VCW) was recorded using continuous-wave Doppler ultrasound from apical, suprasternal, and subcostal windows, and the highest jet velocity was used for calculations. Flow velocity in the left ventricular outflow tract just below the prosthesis (VPW) was recorded by pulse-wave Doppler ultrasound using the apical four-chamber view. The peak and mean Doppler gradients by correction for prevalvular velocity were computed according to the Bernoulli equation: Pressure gradients = 4(VCW2 - VPW2).

Valve orifice area was obtained by dividing stroke volume by the planimetrically measured time velocity integral (TVI) [10]: VOA (cm2) = SV/TVI = SV/{int}0ET V(t) dt, where V is flow velocity. Systemic blood pressure was measured with a cuff sphygmomanometer.

After obtaining the baseline data, dobutamine was infused from the peripheral vein at incremental doses of 5 and 10 µg/kg/min at 10-minute intervals, and the above hemodynamic data were then measured for each dose of dobutamine administration. All volume and Doppler measurements were obtained by averaging five representative beats.

Data analysis
Statistical analysis was done with the Statview program (Statview, Abacus Concepts, Inc, Berkeley, CA) on a Macintosh computer. Values are given as the mean ± standard deviation. Correlation between direct measurements and echocardiograms were assessed by linear regression analysis. The significance of paired data were determined using the Student’s paired t tests. The p values at the dose of 10 µg/kg/min dobutamine infusion were corrected by the Bonferroni inequality equation: Corrected p value = 1 - (1 - p)2. Differences were considered significant at p < 0.05.


   Results
Top
 Abstract
 Introduction
 Material and methods
 Results
Comment
 Acknowledgments
 References
 
Cardiac catheterization
In coronary angiographies, all of the bypass grafts were patent, and the problems of myocardial ischemia were considered to be absent in each case. The average central venous pressure was 5.5 ± 2.9 mmHg (ranged from 2 to 10 mmHg), the peak pulmonary pressure was 26.8 ± 5.0 mmHg (21 to 38 mmHg), the pulmonary capillary wedge pressure was 8.5 ± 3.3 mmHg (4 to 14 mmHg), and the left ventricular end-diastolic pressure was 13.5 ± 5.2 mmHg (5 to 22 mmHg). The mean cardiac output was 4.28 ± 0.51 L/min (ranged from 3.52 to 4.92) and the heart rate was 69.4 ± 9.3 beats/min (58 to 86). Peak-to-peak pressure gradients, instantaneous peak gradients, mean gradients, and valve orifice areas are listed in Table 1.


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  		Table 1. Hemodynamics by Standard Cardiac Catheterization

 
Dobutamine stress echocardiography
During dobutamine infusions, neither ventricular arrhythmias nor the episodes of chest pain were observed in each case, but 3 patients complained of slight palpitations. Changes in cardiac output, systemic peak blood pressure, heart rate, the peak and mean Doppler gradients, left ventricular ejection fraction, and aortic valve area at rest and during dobutamine administration are summarized in Table 2. Cardiac output, systemic peak blood pressure, heart rate, the Doppler gradients, and left ventricular ejection fraction increased after the administration of dobutamine, as expected. The average valve orifice area also increased significantly at the dose of 10 µg/kg/min dobutamine infusion (p < 0.05).


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  		Table 2. Echocardiographic Findings at Rest and During Dobutamine Administration

 
The peak and mean pressure gradients and the valve orifice area measured by cardiac catheterization correlated significantly with those obtained by resting echocardiograms (peak gradient: r2 = 0.82, p < 0.001; mean gradient: r2 = 0.68, p < 0.01; valve orifice area: r2 = 0.76, p < 0.01).


   Comment
Top
 Abstract
 Introduction
 Material and methods
 Results
 Comment
Acknowledgments
 References
 
The permissible range of residual transvalvular pressure gradients across small prostheses remains controversial after aortic valve replacement. Previously, one of the investigators [11] reported that the anticipated reduction of the left ventricular mass in patients with a 21-mm Björk-Shiley valve was only observed in patients with a body surface area of less than 1.45 m2. We have therefore extensively adopted aortic annular enlargement and avoided the use of 19-mm mechanical prostheses. In our previous series of 88 consecutive aortic valve replacements with mechanical prostheses [12], 21 (23.9%) patients underwent concomitant annular enlargement with one (4.8%) hospital death, and 83 (94.3%) received 23-mm or larger valves. Although our results for annular enlargement were satisfactory, aortic cross-clamping and operating times were prolonged. Furthermore, larger amounts of homologous blood transfusion and longer recovery times were sometimes required than those in conventional valve replacement. We recently altered our policy and now use the 19-mm Carpentier-Edwards pericardial valve for elderly patients with a small annulus.

Satisfactory experiences of the durability over 10 years [4, 5] and the excellent manufacturing hemodynamic data were reasons for our choice. However, information regarding the in vivo hemodynamic performance of this bioprosthesis by direct measurement is extremely limited. Cosgrove and associates [13, 14] reported about the hemodynamic performance of the Carpentier-Edwards pericardial, supraannula, and standard porcine bioprostheses, which were directly measured after the cessation of cardiopulmonary bypass, and concluded that the performance of the pericardial valve was superior to that of porcine valves [13]. They also demonstrated that the average peak-to-peak and mean gradients across the 19-mm pericardial valve were 30.4 mmHg and 23.0 mmHg, and that the valve orifice area was 1.1 cm2, and suggested that the 19-mm pericardial valve provided acceptable hemodynamic performance [14].

Left ventricular pressure in patients with a bioprosthesis can be measured by crossing the valve [1]. In patients with a mechanical aortic prosthesis, however, left ventricular pressure cannot be recorded without further invasive methods such as a transseptal technique or transthoracic puncture [15–18]. Consequently, little hemodynamic data is available on mechanical prostheses assessed by cardiac catheterization. The hemodynamic performance of various 19-mm prostheses assessed by standard catheterization found in the literature are listed in Table 3 [1, 15–18]. The listed values were obtained at rest. The average peak-to-peak gradient and mean gradient across the 19-mm St. Jude Medical standard valve [15], the most representative mechanical prosthesis, are considerably higher than those across the 19-mm Carpentier-Edwards pericardial valve. In addition, the mean valve orifice area of the 19-mm Carpentier-Edwards pericardial valve is larger than that of the 19-mm St. Jude Medical valve [15]. The other mechanical valves listed here also demonstrated the same conclusions as for the St. Jude Medical valve.


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  		Table 3. Comparison of In Vivo Hemodynamic Performances of 19-mm Prostheses by Cardiac Catheterization

 
In contrast to hemodynamic data obtained by invasive procedures, a large number of reports are available on the assessments of various 19-mm prostheses by resting echocardiography (Table 4) [6, 7, 16, 19–23]. The peak and mean Doppler gradients across the 19-mm mechanical and Carpentier-Edwards porcine valves ranged higher than those across the 19-mm Carpentier-Edwards pericardial valve. The average valve orifice areas of these prostheses were also conversely smaller. Consequently, we consider that the hemodynamic performance of the Carpentier-Edwards pericardial bioprosthesis is superior to that of the other listed prostheses.


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  		Table 4. Comparison of In Vivo Hemodynamic Performances of 19-mm Prostheses by Resting Echocardiography

 
In evaluating the hemodynamic performance of prostheses, it is considered to be essential to make an assessment both at rest and during exercise. Therefore, echocardiography during dobutamine administration was employed. The average valve orifice area of the 19-mm pericardial valve in this series became significantly larger than its value at rest after the administration of dobutamine, thus the mean Doppler gradient resulted in mild increase. Kadir and associates [19] reported that the mean Doppler gradient across the 19-mm St. Jude Medical standard valve increased to 37.9 ± 10.2 mmHg at a dose of 10 µg/kg/min dobutamine infusion as cardiac output increased to 6.9 ± 2.0 L/min, but the valve orifice area did not increase. Valve orifice areas of bioprostheses increase progressively as flow increases both in vivo [13, 14] and in vitro [24], but that of mechanical prostheses does not increase during exercise [15, 16, 19, 24], according to the literature. The Carpentier-Edwards pericardial valve would thus provide greater hemodynamic advantage than mechanical prostheses during exercise.

In conclusion, the 19-mm aortic Carpentier-Edwards pericardial valve provides acceptable hemodynamic performance in such patients with a body surface area of less than 1.60 m2, and is also more hemodynamically advantageous than mechanical valves during exercise. Use of the 19-mm Carpentier-Edwards pericardial bioprosthesis is thus a reliable option for elderly patients with a small aortic annulus.


   Acknowledgments
Top
 Abstract
 Introduction
 Material and methods
 Results
 Comment
 Acknowledgments
References
 
We gratefully acknowledge the assistance of Mr Teruo Ookubo in performing the echocardiographic examinations. This study was supported by an institutional grant from the Saitama Cardiovascular and Respiratory Center.


   References
Top
 Abstract
 Introduction
 Material and methods
 Results
 Comment
 Acknowledgments
 References
 

  1. Bove E.L., Marvasti M.A., Potts J.L., et al. Rest and exercise hemodynamics following aortic valve replacement: a comparison between 19 and 21 mm Ionescu-Shiley pericardial and Carpentier-Edwards porcine valves. J Thorac Cardiovasc Surg 1985;90:750-755.[Abstract]
  2. Wheatley D.J., Fisher J., Reece I.J., Spyt T., Breeze P. Primary tissue failure in pericardial heart valves. J Thorac Cardiovasc Surg 1987;94:367-374.[Abstract]
  3. Yoganathan A.P., Woo Y.R., Sung H.W., Williams F.P., Franch R.H., Jones M. In vitro hemodynamic characteristics of tissue bioprosthesis in the aortic position. J Thorac Cardiovasc Surg 1986;92:198-209.[Abstract]
  4. Cosgrove D.M., Lytle B.W., Taylor P.C., et al. The Carpentier-Edwards pericardial aortic valve: ten-year results. J Thorac Cardiovasc Surg 1995;110:651-662.[Abstract/Free Full Text]
  5. Pelletier L.C., Carrier M., Leclerc Y., Dyrda I. The Carpentier-Edwards pericardial bioprosthesis: clinical experience with 600 patients. Ann Thorac Surg 1995;60:S297-S302.
  6. Nakajima H., Aupart M.R., Neville P.H., Sirinelli A.L., Meurisse Y.A., Marchand M.A. Twelve-year experience with the 19 mm Carpentier-Edwards pericardial aortic valve. J Heart Valve Dis 1998;7:534-539.[Medline]
  7. McDonald M.L., Daly R.C., Schaff H.V., et al. Hemodynamic performance of small aortic valve bioprostheses: is there a difference?. Ann Thorac Surg 1997;63:362-366.[Abstract/Free Full Text]
  8. Gorlin R., Gorlin S.G. Hydraulic formula for calculation of the area of the stenotic mitral valve, other cardiac valves and central circulatory shunts. Am Heart J 1951;41:1-29.[Medline]
  9. Teichholtz L.E., Cohen M.V., Sonnenblick E.H., Gorlin R. Study of left ventricular geometry and function by B-scan ultrasonography in patients with and without asynergy. N Engl J Med 1974;291:1220-1226.
  10. Skjaerpe T., Hegrenaes L., Halte L. Noninvasive estimation of valve area in patients with aortic stenosis by Doppler ultrasound and two-dimensional echocardiography. Circulation 1985;72:810-818.[Abstract/Free Full Text]
  11. Hashimoto K., Mashiko K., Nakano M., Horikoshi S., Kurosawa K., Arai T. Use of the 21-mm Björk-Shiley monostrut valve in patients with a narrow aortic root. Cardiovasc Surg 1994;2:456-459.[Medline]
  12. Takakura H., Kurosawa H., Nakano M., Hashimoto K., Mashiko K., Sakamoto Y. Enlarging procedure for small aortic annulus. J Cardiol 1995;26(Suppl I):105.
  13. Cosgrove D.M., Lytle B.W., Gill C.C., et al. In vivo hemodynamic comparison of porcine and pericardial valves. J Thorac Cardiovasc Surg 1985;89:358-368.[Abstract]
  14. Cosgrove D.M., Lytle B.W., Williams G.W. Hemodynamic performance of the Carpentier-Edwards pericardial valve in aortic position in vivo. Circulation 1985;72(Suppl II):II146.
  15. Wortham D.C., Tri T.B., Bowen T.E. Hemodynamic evaluation of the St. Jude Medical valve prosthesis in the small aortic anulus. J Thorac Cardiovasc Surg 1981;81:615-620.[Abstract]
  16. Ihlen H., Mølstad P., Simonsen S., et al. Hemodynamic evaluation of the Carbomedics prosthetic heart valve in the aortic position: comparison of noninvasive and invasive techniques. Am Heart J 1992;123:151-159.[Medline]
  17. Schaff H.V., Borkon A.M., Hughes C., et al. Clinical and hemodynamic evaluation of the 19 mm Björk-Shiley aortic valve prosthesis. Ann Thorac Surg 1981;32:50-57.[Abstract]
  18. Foster A.H., Tracy C.M., Greenberg G.J., McIntosh C.L., Clark R.E. Valve replacement in narrow aortic roots: serial hemodynamics and long-term clinical outcome. Ann Thorac Surg 1986;42:506-516.[Abstract]
  19. Kadir I., Izzat M.B., Birdi I., et al. Hemodynamics of St. Jude Medical prostheses in the small aortic root: in vivo studies using dobutamine Doppler echocardiography. J Heart Valve Dis 1997;6:123-129.[Medline]
  20. Chafizadeh E.R., Zoghbi W.A. Doppler echocardiographic assessment of the St. Jude Medical prosthetic valve in the aortic position using continuity equation. Circulation 1991;83:213-223.[Abstract/Free Full Text]
  21. De Paulis R., Sommariva L., Russo F., et al. Doppler echocardiographic evaluation of the Carbomedics valve in patients with small aortic anulus and valve prosthesis-body surface area mismatch. J Thorac Cardiovasc Surg 1994;108:57-62.[Abstract/Free Full Text]
  22. Kirzner C.F., Vinals B., Moya J., et al. Hemodynamic performance evaluation of small aortic ATS Medical valve by Doppler echocardiography. J Heart Valve Dis 1997;6:661-665.[Medline]
  23. Bojar R.M., Rastegar H., Payne D.D., Mack C.A., Schwartz S.L. Clinical and hemodynamic performance of the 19-mm Carpentier-Edwards porcine bioprosthesis. Ann Thorac Surg 1993;56:1141-1147.[Abstract]
  24. Baumgartner H., Khan S.S., DeRobertis M., Czer L.S., Maurer G. Doppler assessment of prosthetic valve orifice area: an in vitro study. Circulation 1992;85:2275-2283.[Abstract/Free Full Text]



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