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Eur J Cardiothorac Surg 2000;17:134-139
© 2000 Elsevier Science NL

Reoperative surgery for degenerated aortic bioprostheses: predictors for emergency surgery and reoperative mortality

Clinic for Cardiovascular Surgery and Cardiology, University Hospital, Rämistrasse 100, CH-8091 Zurich, Switzerland

Corresponding author. Tel.: +41-1-255-1111; fax: +41-1-255-4446
e-mail: paul.vogt{at}chi.usz.ch

	Abstract

Top Abstract 1. Introduction 2. Materials and methods 3. Results 4. Discussion Appendix A Appendix B. Conference... References

 
Objective: The long-term outcome of patients with aortic bioprosthetic valves could be improved by decreasing the reoperative mortality rate. Methods: Predictors of emergency reoperation and reoperative mortality were identified retrospectively in 172 patients who had the first bioprosthetic aortic valve replacement between 1975 and 1988 (mean age 46±13 years) and were subjected to replacement of the degenerated bioprostheses between 1978 and 1997 (mean age 56±14 years). Emergency reoperation had to be performed in 31 patients (18%). Results: The operative mortality was 5.2% (9/172), 22.6% for emergency (odds ratio 11.17; 95%-confidence limit 4.33–28.85) and 1.4% for elective replacement of the degenerated aortic bioprosthesis (P<0.0001; OR=20.3). Patients who died at reoperation had higher transvalvular gradients before the primary aortic valve replacement (P=0.007), received smaller bioprostheses at the first operation (P=0.03), had later recurrence of symptoms after the first aortic valve replacement (P=0.04), a higher pre-reoperative New York Heart Association (NYHA) class (P=0.02), and a higher incidence of coronary artery disease (P=0.001) and pulmonary artery hypertension (P=0.009). Endocarditis before the primary aortic valve replacement (P=0.004), postoperative pneumonia at the first operation (P=0.005), pulmonary hypertension (P=0.0004) acquired during the interval, later recurrence of symptoms (P=0.04) after the first operation, a lower ejection fraction at the time of reoperation (P=0.03) and acute onset of bioprosthetic regurgitation (P=0.00002) were predictors for emergency surgery. Higher transvalvular gradients at the primary aortic valve replacement (P=0.006), coronary artery disease (P=0.003) acquired during the interval, the need for concomitant coronary artery revascularization (P=0.001), sex (P=0.02) and size (P=0.05) and type of the bioprostheses used (P=0.007) were incremental predictors for reoperative mortality which were independent of emergency surgery. Conclusions: Elective replacement of failed aortic bioprostheses is safe. Patients undergoing emergency reoperation have a considerably higher mortality. They can be identified by a history of native aortic valve endocarditis, higher transvalvular gradients at primary aortic valve replacement, smaller bioprostheses, and pulmonary hypertension or coronary artery disease acquired during the interval. A failing bioprosthesis must be replaced at its first sign of dysfunction.

Key Words: Degenerated aortic bioprosthesis • Reoperation • Predictors • Mortality

	1. Introduction

Top Abstract 1. Introduction 2. Materials and methods 3. Results 4. Discussion Appendix A Appendix B. Conference... References

 
There are only a few generally accepted indications to use a bioprosthesis for primary isolated aortic valve replacement such as established contraindications to continuous anticoagulation, the lack to adequately regulate the prothrombin time and the elderly patients whose survival is limited and more dependent on non-valve related complications [1]. An increasing wealth of information about the expected lifetime of porcine aortic valves [2] and long-term comparisons between mechanical and biological valves regarding risk and benefits, valve-related complications and quality of life are available [3]. However, the most appropriate valve substitute for the individual patient is still debatable and age alone is not a valid criteria for therapeutic decisions.

The inherent structural degeneration of bioprostheses is the leading cause and the most frequent indication for reoperation in patients with bioprosthetic valves [4]. The operative mortality for valvular reoperation is still significantly higher than for the primary operation [5,6]. Thus, the decision to use a bioprosthesis for primary isolated aortic valve replacement requires the lowest possible reoperative mortality to improve the long-term outcome in recipients of porcine aortic valves. The objectives of this study were to analyze predictors for hospital mortality in patients undergoing reoperation for primary tissue failure of aortic bioprostheses, to identify predictors for emergency reoperation and to find ways to reduce the incidence of emergency surgery in these patients.

	2. Materials and methods

Top Abstract 1. Introduction 2. Materials and methods 3. Results 4. Discussion Appendix A Appendix B. Conference... References

 
2.1. Patients
Hospital charts were retrospectively reviewed from all patients who had isolated aortic valve replacement with a bioprosthesis between 1975 and 1988 and were subsequently subjected to re-replacement of the failed bioprostheses between 1978 and 1997. A total of 172 patients could be identified, 140 men (81%) and 32 women (19%). Mean age was 46±13 years (range 16–70 years) at the first operation, and it was 56±14 years (range 20–82 years) at the time of reoperation.

2.2. Primary aortic valve replacement
Reasons for primary aortic valve replacement were bicuspid aortic valve stenosis in 36 patients (21%), acquired non-rheumatic aortic valve disease in 81 (47%), rheumatic heart valve disease in 32 (18%) and native aortic valve endocarditis in 25 (14%). A mild to moderate concomitant mitral valve regurgitation was found in 34 patients (20%) but left untreated in all. Preoperatively, pure aortic valve incompetence was identified in 52 patients (30%), aortic valve stenosis in 35 (20%) and combined aortic valve disease in the remaining 85 (50%) (Table 1). Mean pulmonary artery pressure was 18.4±8.3 mmHg (range 9–65 mmHg). Chronic atrial fibrillation was present in two patients (1.2%). The mean preoperative New York Heart Association (NYHA) class was 2.5±0.9 with 23 patients (13%) in class I, 83 (49%) in class II, 43 (25%) in class III and 23 (13%) in class IV.

2.3. Interval
There were 15 cases (9%) of bioprosthetic valve endocarditis between the primary aortic valve replacement which were reoperated after a mean of 5±4 years (range 1.5 months–13.5 years).

The mean overall life expectancy of all aortic bioprostheses was 125±52 months (range 2–343 months) and this did not differ between the various types of prostheses used. The interval between the first clinical signs indicating deterioration of the bioprosthesis and the reoperation was 6±8 months (range 1–45 months).

2.4. Re-replacement for bioprosthetic valve dysfunction
Elective reoperative surgery was performed in 141 patients (82%). Emergency surgery was necessary in 31 (18%) patients with acute bioprosthetic valve dysfunction presenting pronounced cardiac failure, overt pulmonary edema and secondary organ dysfunction due to the acute low cardiac output. The pre-reoperative patient characteristics are listed in Table 2. Preoperative lung edema was diagnosed in 27 patients (16%). Concomitant coronary artery disease was found in 54 patients (31%), with bypass grafting performed in 26 (15%).

The bioprostheses is grasped with a clamp and traction away from the aortic wall is exerted to divide the attachment of the prosthetic valve sewing ring starting at the most convenient sinus. Excision of the bioprostheses is achieved by first incising along the prongs, thus preserving the cloth and the native tissue of the aortic wall to prevent destruction of the adjacent structures such as the coronary ostia, the interventricular septum, the His-bundle or the ventriculo-aortic continuity. This is especially important in previously oversized bioprostheses which may be deeply embedded their struts being fused to the aortic wall. A new prosthetic valve device is implanted using interrupted 2-0 braided non-absorbable sutures. Concomitant coronary artery bypass grafting is performed in standard fashion and usually is done before implantation of the new aortic valve prosthesis. Closure of the aortotomy, rewarming, weaning from cardiopulmonary bypass, decannulation and wound closure are performed by standard techniques.

The mean cardiopulmonary bypass time was 104±64 min (range 46–480 min) with a mean aortic cross clamp time of 60±23 min (range 26–142 min).

2.6. Statistical analysis
Data are presented as mean±SD (range) and frequencies (percent). Categorical data were assessed by means of Pearson ² or Fisher's exact test as appropriate to compare preoperative patient data and postoperative complications. Continuous data were compared by means of an unpaired t-test or Mann–Whitney U-test as appropriate. The odds ratio was assessed by univariate logistic regression. A stepwise multivariate logistic regression analysis was performed to assess independent predictors of emergency reoperation and reoperative mortality including all perioperative patients data of the first aortic valve replacement as well as of the re-replacement for bioprosthetic valve dysfunction. (Appendix A). Values of P<0.05 were considered to be of statistical significance. All calculations were performed with the use of the statistical package SPSS for Windows 6.1 (SPSS, Inc, Chicago, IL).

	3. Results

Top Abstract 1. Introduction 2. Materials and methods 3. Results 4. Discussion Appendix A Appendix B. Conference... References

 
3.1. Predictors of reoperative mortality
The overall 30-day mortality rate for re-replacement of the degenerated aortic bioprostheses was 5.2% (9/172 patients). Mortality was 1.4% (2/141) in patients with elective reoperation whereas it was 22.6% (7/31) for those undergoing emergency re-replacement (P<0.0001, OR=20.3). Reoperative survivors were more likely to have received a larger sized (27.4±2 vs. 26.0±2 mm; P=0.03, OR=0.70 per mm) Carpentier–Edward's bioprosthesis (78 vs. 22%, P<0.001, OR=0.08) and to have been free from any perioperative complication at the first operation (11 vs. 38%, P=0.04, OR=4.8). In addition, they had a lower NYHA class at the time of reoperation (2.7±0.9 vs. 3.6±0.7; P=0.02, OR=3.7 per class) and had less acute bioprosthetic valve incompetence (28 vs. 78%, P=0.004, OR=9.0).

Those who died at reoperation were more likely to have associated symptomatic double or triple-vessel coronary artery disease (75 vs. 17%; P<0.001, OR=14.5), preoperative lung edema (50 vs. 14%; P=0.02, OR=6.0) and pulmonary artery hypertension (mean pulmonary artery pressure 35±10 vs. 23±9 mmHg; P=0.009, OR=1.10 per mmHg) diagnosed at the time of re-replacement. In addition, they were older (55±11 vs. 45±13 years; P=0.04, OR=1.06 per year) and were found to have had higher transvalvular pressure gradients at their first aortic valve replacement (73±30 vs. 45±2 mmHg; P=0.007, OR=1.03 per mmHg).

The interval between the first operation and the onset of first signs of a deteriorating bioprosthesis was shorter in those who died at reoperation (6.9±3.7 vs. 10.0±4.2 years, P=0.04, OR=0.83 per year). In addition, time from onset of symptoms to reoperation tended to be shorter in those who died at reoperation (2.4±2.5 months vs. 6.7±9.1 months; P=0.07, OR=0.82 per month). Left ventricular outflow tract enlargement at the first operation did not increase the risk of bioprosthetic re-replacement. In addition, older age at reoperation, decreased left ventricular ejection fraction and longer cardiopulmonary bypass and aortic cross clamp time were not found to increase the risk of death at reoperation.

The mean duration of postoperative intensive care stay was 3±4 days for patients with elective re-replacement and 4±4 for those undergoing emergency surgery (P=0.11) (hospital deaths excluded). However, the mean duration of hospitalization was 24±23 days after emergency surgery whereas it was 14±7 days for those undergoing elective re-replacement (P=0.05). Postoperatively, the mean NYHA class was 1.8±0.5 and did not differ between groups.

Older age, sex, associated coronary artery disease and concomitant coronary revascularization at reoperation, type and size of the bioprosthesis used and the transvalvular gradient at the first operation increased risk of death at re-replacement independently of emergency surgery (Table 3).

3.2. Predictors for emergency reoperation
Endocarditis prior to first operation (32 vs. 11%, P=0.004, OR=4.1), postoperative pneumonia at the first operation (16 vs. 2%, P=0.005, OR=8.9), long standing bioprosthetic incompetence (23 vs. 75%, P<0.00001, OR=0.10), acute bioprosthetic regurgitation (65 vs. 23%, P=0.00002, OR=6.1), pulmonary artery hypertension at the time of reoperation (73 vs. 34%, P=0.0004, OR=5.2), pre-reoperative left ventricular ejection fraction (48±14 vs. 55±11%, P=0.03, OR=0.96 per %) and the degree of bioprosthetic regurgitation (62±9 vs. 53±14%, P=0.003, OR=1.07 per %) were found to be predictive factors for emergency replacement of the dysfunctional bioprosthesis. The interval between the first operation and the onset of symptoms of deterioration (122±50 vs. 101±52 months, P=0.04, OR=0.99 per month) was longer, whereas the interval between the onset of symptoms and the time of reoperation were shorter in those undergoing emergency surgery (2.0±3.2 vs. 7.5±9.5 months; P=0.0001). Logistic regression analysis identified four independent predictors for emergency reoperation which are summarized in Table 4. However, the sensitivity (75%) and the positive predictive value (42%; odds ratio 11.17; 95%-CI 4.33–28.85) to estimate an individual 20% risk of undergoing emergency surgery was disappointingly low. Nevertheless, the negative predictive value was acceptable (94%).

	4. Discussion

Top Abstract 1. Introduction 2. Materials and methods 3. Results 4. Discussion Appendix A Appendix B. Conference... References

Ideally, the hospital mortality after aortic valve re-replacement should be identical to those of the equivalent primary valve procedure to improve the long-term outcome of patients receiving tissue valves. Reoperations are technically more demanding and many patients present in a poor functional state with hemodynamic deterioration, increasing the reoperative mortality rate of failing aortic bioprostheses up to 19% [2,4,5]. However, as shown in this study as well as in others [11], elective replacement of malfunctioning aortic bioprostheses can be performed with results equal to the primary operation.

Reoperative survivors had had a higher transvalvular gradient at the time of the first operation, were more likely to be women and had received smaller bioprostheses. In addition, the diagnosis of coronary artery disease or pulmonary artery hypertension acquired late after the first operation, was an important predictor of reoperative survival and these predictors were independent from emergency surgery. Therefore, the presence of concomitant coronary artery disease and pulmonary artery hypertension clearly identifies patients being at considerably higher risk at reoperation and these patients need careful surveillance once the probability of bioprosthetic dysfunction increases 6–7 years after implantation [12].

Emergency surgery is the most important factor determining operative outcome yielding a consistently high early mortality up to 25–44% [13]. Primary tissue failure of porcine bioprostheses is believed to develop gradually, allowing elective operation. However, a substantial number of patients, 18% in this study, required emergency reoperation for acute tissue failure presenting with pronounced cardiac failure, overt pulmonary edema and secondary organ manifestations due to the low cardiac output. In this study, seven out of 172 patients (4%) with failing bioprostheses arrived at the operating theatre with full cardiopulmonary resuscitation although the onset of bioprosthetic degeneration was known. This emphasizes the importance of minimizing the number of patients requiring emergency reoperation and the most rational approach to this problem is prevention.

Thus, an important objective of this study was to identify predictors for emergency reoperation and to find ways to reduce the incidence of emergency surgery in patients with malfunctioning bioprostheses. We found, that patients requiring emergency surgery were more likely to have the following characteristics: a history of endocarditis prior to the first operation, in-hospital pneumonia at the first operation, pulmonary artery hypertension acquired during the interval, decreased left ventricular ejection fraction before redo surgery, acute bioprosthetic regurgitation and a higher degree of bioprosthetic incompetence. Surprisingly, endocarditis prior to the first operation and perioperative pneumonia were the most important independent predictors for emergency surgery. Although hypothetical, an altered immunological mechanism may be suggested in these patients, leading to an increased incidence of infections and an alternative way of bioprosthetic degeneration.

The time between the onset of first clinical signs of a malfunctioning bioprosthesis and the time of reoperation was statistically significantly shorter in those requiring emergency surgery and this is consistent with other studies [13] indicating acute leaflet rupture. Therefore, long-standing bioprosthetic incompetence was not a predictor for emergency reoperation. Nevertheless, the mean duration of clinical symptoms before emergency re-replacement was at least 2 months and none of the patients were asymptomatic, providing still sufficient time for proper planning of the reoperation.

The sensitivity and the ability to positively predict emergency surgery in our patients was disappointingly low and proper identification of patients requiring emergency surgery for malfunctioning aortic bioprostheses seems to be difficult. However, the negative predictive value of the independent predictors for emergency reoperation was 94%.

Thus, the following variables are thought to be clinically relevant to the management of patients with bioprostheses with regard to surveillance and timing of reoperation to decrease the reoperative mortality and the incidence of emergency surgery: a history of endocarditis prior to the first operation, a high transvalvular gradient at the primary operation, small aortic bioprostheses, perioperative infectious complications, coronary artery disease acquired after the first operation, an increase in pulmonary artery pressure and a decrease in the left ventricular function during the interval.

Proper timing of the reoperation is emphasized, because the duration of clinical signs of a deteriorating aortic bioprosthesis is misleading and this is clearly demonstrated in our study. Even seemingly ‘acute’ leaflet rupture of a degenerating tissue valve, requiring emergency surgery, usually is heralded by clinical symptoms and can be prevented.

The use of a Carpentier–Edward's bioprosthesis has found to be a predictor of reoperative survival in this group patients, a finding which is difficult to explain as all variables listed in Appendix A were equally distributed between groups. In addition, the number of patients with bioprosthesis other than a Carpentier–Edwards-type is very limited in this study preventing reasonable conclusions.

In conclusion, early reoperation of failing aortic bioprostheses is advised as soon as the necessity for re-replacement becomes evident to reduce the incidence of emergency surgery and reoperative mortality, to improve the long-term outcome of patients with tissue valves and to reduce the overall costs of treatment.

	Footnotes

 
Presented at the 13th Annual Meeting of the European Association for Cardio-thoracic Surgery, Glasgow, Scotland, September 5–8, 1999.

	Appendix A

Top Abstract 1. Introduction 2. Materials and methods 3. Results 4. Discussion Appendix A Appendix B. Conference... References

 
1. Preoperative patient characteristics

Age

Sex

Degenerative aortic valve disease

Congenital aortic valve disease

Postrheumatic valve disease

Endocarditis of the native aortic valve

NYHA class

Heart rhythm

Left ventricular ejection fraction

Mean transvalvular gradient

Regurgitation fraction

Pulmonary artery pressure

Wedge pressure

2. Primary aortic valve replacement

Age at re-replacement

Type and size of bioprosthesis used

Cardiopulmonary bypass time

Aortic cross clamp time

Left ventricular outflow tract enlargement

Perioperative myocardial infarction

Cerebro-vascular incident

Pneumonia

Infectious endocarditis

3. Interval

Postoperative NYHA class.

Heart rhythm

Left ventricular ejection fraction

Paravalvular leakage

Infectious endocarditis

Chronic regurgitation

Acute regurgitation

Coronary artery disease

Pulmonary hypertension

Interval between 1° and 2° operation

Interval onset of clinical signs to re-replacement

4. Reoperation

Age at reoperation

Year of reoperation

Elective reoperation

Emergency surgery

Pre-reoperative lung edema

Transprosthetic pressure gradient

Regurgitation fraction

LVEDD

LVESD

Pulmonary artery pressure

Cardipulmonary bypass time

Aortic cross clamp time

	Appendix B. Conference discussion

Top Abstract 1. Introduction 2. Materials and methods 3. Results 4. Discussion Appendix A Appendix B. Conference... References

 
Dr D. Saksena (Bombay, India): I would like to re-emphasize that some of these patients who are having biological prostheses, when they start degenerating it is believed that you can wait and have elective time for surgery. Some of these degenerate so fast that you have to have emergency surgery, and the question I have for you is, first of all, what you have said, that you should operate on them earlier, which is the true policy for this. All these patients that you need required emergency surgery that had high mortality, were they being followed by the surgeons or by the cardiologists?

Dr Vogt: All these patients were followed by cardiologists, and then were sent to the cardiac surgeon. I think, a bioprosthesis should be operated on at the first clinical sign of deterioration. This would reduce the life expectancy of these bioprostheses for about 4–6 months, nevertheless, the overall reoperative mortality would be substantially decreased.

Dr D. Blyth (Durban, South Africa): I couldn't agree more that the timing of surgery is imperative. In our series of about 350, we have had a mortality rate of 6%, and that has been very badly hit by emergency replacement for the mechanical prosthetic group. The tissue group allows you considerable leeway.

The other comment I would make is that, I think I understood you correctly, that with the redos you have to put in a smaller valve. I certainly wouldn't hesitate to enlarge the root if I can't get a satisfactory valve in, but in fairness, I think perhaps your group is older. We are operating on mainly rheumatic fever patients. Would you comment?

Dr Vogt: We included patients with coronary artery disease, when acquired between the first and second procedure, because this is a predictor for increased risk of reoperation. In addition, cardiologists may be able to better identify those patients who are at increased risk to undergo emergency redo surgery.

Concerning valve size, usually we implant one size lower, however, if the valve size is too small for a particular patient, we enlarge the aortic root in the redo as well.

	References

Top Abstract 1. Introduction 2. Materials and methods 3. Results 4. Discussion Appendix A Appendix B. Conference... References

 

1. Borkon A.M., Soule L.M., Baughman K.L., Baumgartner W.A., Gardner T.J., Watkins L., Gott V.L., Hall K.A., Reitz B.A. Aortic valve selection in the elderly patient. Ann Thorac Surg 1988;46:270-277.[Abstract]
2. Jamieson W.E.R., Munro A.I., Miyagishima R.T., Allen P., Burr L.H., Tyers G.F.O. Carpentier–Edwards standard porcine bioprosthesis: clinical performance to seventeen years. Ann Thorac Surg 1995;60:999-1007.[Abstract/Free Full Text]
3. Mykén P.S.U., Caidahl K., Larsson P., Larsson S., Wallentin I., Berggren H.E. Mechanical versus biological valve prosthesis: a ten-year comparison regarding function and quality of life. Ann Thorac Surg 1995;60:S447-S452.
4. Cohn L.H., Collins J.J., DiSesa V.J., Couper G.S., Peigh P.S., Kowalker W., Allred E. Fifteen-year experience with 1678 Hancock porcine bioprosthetic heart valve replacements. Ann Surg 1989;210:435-442.[Medline]
5. Bloomfield P., Wheatley D.J., Prescott R.J., Miller H.C. Twelve-year comparison of a Björk-Shiley mechanical heart valve with porcine bioprostheses. N Engl J Med 1991;324:573-579.[Abstract]
6. Bortolotti U., Milano A., Mossuto E., Guerra F., Rubino M., Rizzoli G., Mazzucco A., Gallucci V. The risk of reoperation in patients with bioprosthetic valves. J Card Surg 1991;6:638-643.[Medline]
7. Manouguian S., Seybold-Epting W. Patch enlargement of the aortic valve ring by extending the aortic incision in to the anterior mitral leaflet: new operative technique. J Thorac Cardiovasc Surg 1979;78:402-412.[Abstract]
8. Milano A., Guglielmi C., De Carlo M., Di Gregorio O., Borzoni G., Verunelli F., Bortolotti U. Valve-related complications in elderly patients with biological and mechanical aortic valves. Ann Thorac Surg 1998;66:S82-S87.
9. Starr A., Grunkemeier G.L. The expected lifetime of porcine valves. Ann Thorac Surg 1989;48:317-318.[Medline]
10. Edmunds L.H., Jr Thrombotic and bleeding complications from prosthetic heart valves. Ann Thorac Surg 1987;44:430-445.[Abstract]
11. Antunes M.J. Isolated replacement of a prosthesis or a bioprosthesis in the aortic valve position. Am J Cardiol 1987;59:350-352.[Medline]
12. Turina J., Hess O.M., Turina M., Krayenbuehl H.P. Bioprostheses in the 1990s. Circulation 1993;88:775-781.[Free Full Text]
13. Bortolotti U., Guerra F., Magni A., Milano A., Mazzucco A., Talenti E., Thiene G., Gallucci V. Emergency reoperation for primary tissue failure of porcine bioprostheses. Am J Cardiol 1987;60:920-921.[Medline]

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