Ann Thorac Surg 2001;72:28-32
© 2001 The Society of Thoracic Surgeons
Original article: cardiovascular
Aortic root replacement versus aortic valve replacement: a case-match study
Paul P. Urbanski, MDa,
Matthias Wagner, MDa,
Michael Zacher, MDa,
Robert W. Hacker, MDa
a Herz- und Gefaess-Klinik, Bad Neustadt, Germany
Accepted for publication March 15, 2001.
Address reprint requests to Dr Urbanski, Herz- und Gefaess-Klinik, Salzburger Leite 1, 97616 Bad Neustadt, Germany
e-mail: urbanski{at}kardiochirurg.de
 |
Abstract
|
|---|
Background. There is increasing evidence that patients with aortic valve disease and dilatation of the ascending aorta are at risk for later dissection or rupture of the aortic wall when the dilated ascending aorta is not replaced or reinforced at the time of aortic valve replacement. In order to find out whether the more complex surgical procedure of aortic root replacement carries a higher early or late postoperative risk than isolated aortic valve replacement, we conducted a matched-pair study with patients of both groups.
Methods. Between June 1993 and August 1998, 100 consecutive patients with aortic valve disease and ectasia/aneurysm of the ascending aorta underwent replacement of the aortic valve and the ascending aorta with a CarboSeal composite graft (CarboSeal; Sulzer CarboMedics Inc, Austin, TX). Identical bileaflet valve prostheses (CarboMedics; Sulzer CarboMedics Inc, Austin, TX) were implanted during the same time period in 928 patients for aortic valve disease. On the basis of various preoperative clinical variables 100 patients with aortic valve replacement were matched to the 100 patients with replacement of the aortic root. The duration of follow-up for both groups was similar with 37 + 17 months (range, 9 to 70) for the CarboSeal group and 38 + 14 months (range, 13 to 65) for the CarboMedics group. Survival and morbidity were calculated by Kaplan-Meier analysis and risk-adjusted mortality was evaluated by multivariate analysis in a Cox regression model.
Results. The early postoperative mortality of 1% in the CarboSeal group and 4% in the CarboMedics group was insignificantly different. Although the overall survival rate at 5 years was lower (60.7% vs 86.3%; p = 0.13) in the CarboSeal group, the freedom from cardiac mortality and valve-related morbidity was similar in the two groups.
Conclusions. Replacement of the ascending aorta and aortic valve can be performed with similar operative risk, valve-related morbidity, and late cardiac mortality as isolated aortic valve replacement.
|
Introduction
|
|---|
Total replacement of the aortic root described by Bentall and De Bono [1] has been supplemented by various technical modifications and has become a standard surgical procedure [2]. The operative results as well as the perioperative mortality and morbidity have been improved due to increased experience and development of the prosthetic implants, (ie, the coating of the vascular prosthesis) [3, 4]. Many patient-related aspects and the surgical experience of the surgeon must be considered when evaluating the indication for replacement of the ascending aorta. In borderline patients, the surgeon can be confronted with a difficult decision, when, in addition to a diseased aortic valve, there is a dilatation of the ascending aorta to a diameter of approximately 5 cm, which in itself would not yet constitute an indication for an operation. However, in the presence of aortic valve disease, concomitant replacement of the ascending aorta should be considered, especially in the presence of annulo-aortic ectasia, bicuspid aortic valve or Marfan’s syndrome. The patient’s age, sex, and body surface should also be taken into consideration [5]. This retrospective study was conducted in order to compare the operative risk and medium-term outcome for patients after aortic root replacement versus patients after isolated aortic valve replacement.
|
Patients and methods
|
|---|
Between June 1993 and August 1998, 100 consecutive patients, requiring aortic valve operations with an aneurysm or dilatation of the ascending aorta in diameter of more than 4.5 cm, underwent aortic root replacement using a valved composite graft (CarboSeal; Sulzer CarboMedics Inc, Austin, TX) at our institution. This composite graft consists of a bileaflet CarboMedics valve prosthesis and a gelatin-impregnated, woven polyester tube.
During the same time period, 928 patients with aortic valve disease, but without dilatation of the ascending aorta, underwent aortic valve replacement using the identical valve prosthesis (CarboMedics; Sulzer CarboMedics Inc, Austin, TX).
Of these 928 patients, a matched group of 100 patients was selected. The matching variables were age, height and body weight, left ventricular ejection fraction, New York Heart Association functional class, type and severity of the aortic valve disease, diabetes mellitus. However, in contrast to the CarboSeal group, these patients had a normal caliber of the aorta ascendens.
Both groups showed a similar incidence of prior heart operations, prior neurologic events, hypertension, peripheral occlusive disease, chronic-obstructive pulmonary disease and emergencies. Also, at first the incidence of coronary heart disease seemed to be similar (46 in the CarboSeal group versus 40 in the CarboMedics group; p = 0,470). However later, while evaluating the operative data, a surprisingly significant higher incidence of bypass operations was shown in the CarboMedics group. In Table 1 it can be seen that there is an unequal distribution of significant coronary heart disease (a stenosis greater than 50%). The number of female patients was significantly higher in the CarboSeal group. Both variables had no influence on survival by multivariate statistical analysis.
Although there was no basic difference in the intraoperative management of patients, the duration of extracorporeal circulation and aortic cross-clamp time were noticeably longer in the CarboSeal group for reasons associated with the extent of the operation. There was also a significant difference with regard to the lowest rectal temperature.
Complete replacement of the ascending aorta was performed using a modified Bentall technique with aortic wall resection. The coronary ostia were reimplanted using a button technique. Distal aortic anastomosis was performed in an open technique under circulatory arrest in a total of 18 patients. Total aortic arch replacement was carried out in 3 patients. Operative data are presented in Table 2.
The follow-up was complete for all patients. The duration of the follow-up was similar in both groups. The mean follow-up time was 37 + 17 months (range, 9 to 70 months) for the CarboSeal group and 38 +14 months (range, 13 to 65 months) for the CarboMedics group.
Postoperative complications were analyzed according to the "Guidelines For Reporting Morbidity and Mortality after Cardiac Valve Operations" [6]. All statistical analyses were performed with the SPSS program (SPSS for Windows, version 6.3, SPSS Inc, Chicago, IL). The continuous preoperative clinical data of the two groups were compared by t test for matched pairs, and by categorical variables with Wilcox or McNemar tests. Longitudinal data, such as actuarial survival and freedom from morbid events, were estimated by the Kaplan-Meier method. Values were expressed as means and standard deviations. The risk-adjusted mortality was evaluated in a Cox regression model.
|
Results
|
|---|
Early mortality and morbidity
There was no significant difference between the early mortality (30 days) of the two groups (Table 3). In the CarboSeal group 1 patient died as a result of multiorgan failure, following a prolonged hemorrhagic shock due to massive intraoperative bleeding. This patient had three re-thoracotomies for bleeding. In the CarboMedics group 4 patients died within 30 days after surgery, 3 of them as a result of a low cardiac output syndrome and 1 as a result of cardiac arrest. One stroke with permanent neurologic deficits occurred in each group. Rethoracotamy for bleeding was necessary in 7 patients of the CarboSeal group and in 6 patients of the CarboMedics group.
Perioperative myocardial infarction occurred in 1 patient of the CarboMedics group. This patient had already undergone prior coronary artery bypass grafting and replacement of the aortic valve. The patient eventually died due to low cardiac output.
Patient survival
A total of 23 patients died in the CarboSeal group and 12 in the CarboMedics group. Figure 1 shows the actuarial survival for both groups. Although the overall survival rate for the first group was noticeably lower, although not significantly lower, the freedom from cardiac deaths was almost identical in the two groups (Fig 2). The causes of death are given in Table 4. A cardiac cause was found in 13 patients of the CarboSeal group and in 12 patients of the CarboMedics group.
View larger version (13K):
[in this window]
[in a new window]
|
Fig 1. Overall survival after aortic root replacement with the CarboSeal prosthesis and aortic valve replacement with the CarboMedics prosthesis.
|
|
View larger version (13K):
[in this window]
[in a new window]
|
Fig 2. Freedom from cardiac death after aortic root replacement with the CarboSeal prosthesis and aortic valve replacement with the CarboMedics prosthesis.
|
|
Valve-related morbidity
There were no structural defects of either the valve prosthesis or the valved conduit. Hemorrhagic episodes occurred in 7 patients of the CarboSeal group and in 6 patients of the CarboMedics group. Massive gastrointestinal hemorrhage occurred in 1 patient that resulted in death. Thromboembolic events occurred in 2 patients with a valved conduit (1 cerebral and 1 peripheral) and in 3 patients after valve replacement (all cerebral). Prosthetic endocarditis occurred in 3 patients of the CarboSeal group and in none of the patients of the CarboMedics group. It is notable that the conduit infection led to the death of all 3 patients. In 2 of these patients, a reoperation was performed to replace the conduit. There were no other reoperations in either group of patients. Figure 3 shows the freedom from valve-related complications.
View larger version (13K):
[in this window]
[in a new window]
|
Fig 3. Freedom from any valve-related complication after aortic root replacement with the CarboSeal prosthesis and aortic root replacement with the CarboMedics prosthesis.
|
|
After screening of the 44 available variables, the following variables were identified as univariate risk factors for overall survival: diabetes mellitus, emergency or urgent operation, New York Heart Association functional class IV, implant CarboSeal, coronary heart disease, prior neurologic events, and arterial occlusive disease. Significant predictors of long-term survival were determined by multivariate analysis from these variables using the Cox regression model as shown in Table 5.
|
Comment
|
|---|
The aortic diameter plays a decisive role in determining the indication for replacement of the ascending aorta. If the aortic valve is not involved in the pathologic process and there is no Marfan’s syndrome, a diameter of more than 5.5 cm is generally considered an indication for replacement [7]. With an aortic valve replacement, the aorta should be concurrently resected in the presence of degenerative dilatation to avoid late dissection [8, 9]; the individual surgeon generally decides this indication, especially because there are no natural history studies on this. We established the indication for the simultaneous replacement of the ascending aorta if, in addition to an aortic valve requiring an operation, there was an aneurysm or dilatation of the ascending aorta with a diameter of more than 4.5 cm. In these patients, we exclusively used a valved composite graft. We would see the indication for a combined replacement of the aortic valve and the aorta ascendens only in patients where there was an isolated dilatation of the ascending aorta above the sinotubular junction with a nondilatated aortic root. Generally this is not seen very often, and this was not observed by us during the period in which the study took place.
In order to determine whether replacement of the ascending aorta in addition to aortic valve replacement is associated with a higher risk than isolated valve replacement alone, this retrospective matched pair study was carried out. The results should facilitate the decision for a more aggressive approach towards resection of a dilated ascending aorta in combination with aortic valve replacement, at least for the experienced surgeon. Both the preoperative patient data and the operative results in the two groups are comparable with those reported by other authors who have implanted the same or similar devices [10–14].
In our experience, replacement of the aortic valve and the ascending aorta with a valved conduit can be performed with approximately the same risks and results as isolated aortic valve replacement with the exception of a higher, noncardiac-related late death rate in the CarboSeal group, for which no cause could be found. The multivariate statistical analysis showed that the coronary heart disease had no influence on the overall mortality. Therefore, this should not influence the decision for a simultaneous replacement of the aorta ascendens, especially in young patients.
|
Footnotes
|
|---|
This article has been selected for the open discussion forum on the STS Web site: http://www.sts.org/section/atsdiscussion/
|
References
|
|---|
-
Bentall H., De Bono A. A technique for complete replacement of the ascending aorta. Thorax 1968;23:338-339.[Abstract/Free Full Text]
-
Svensson L.G., Crawford E.S., Hess K.R., Coselli J.S., Safi H.J. Composite valve graft replacement of the proximal aorta: comparison of techniques in 348 patients. Ann Thorac Surg 1992;54:427-439.[Abstract]
-
Shapira O.M., Aldea G.S., Cutter S.M., Fitzgerald C.A., Lazar H.L., Shemin R.J. Improved clinical outcomes after operation of the proximal aorta: a 10-year experience. Ann Thorac Surg 1999;67:1030-1037.[Abstract/Free Full Text]
-
Stowe C.L., Baertlein M.A., Wierman M.D., Rucker M., Ebra G. Surgical management of ascending and aortic arch disease: refined techniques with improved results. Ann Thorac Surg 1998;66:388-395.[Abstract/Free Full Text]
-
Ergin M.A., Spielvogel D., Apaydin A., et al. Surgical treatment of the dilated ascending aorta: when and how?. Ann Thorac Surg 1999;67:1834-1839.[Abstract/Free Full Text]
-
Edmunds L.H., Jr, Clark R.E., Cohn L.H., Grunkemeier G.L., Miller D.C., Weisel R.D. Guidelines for reporting morbidity and mortality after cardiac valvular operations. Ann Thorac Surg 1996;62:932-935.[Abstract/Free Full Text]
-
Coady M.A., Rizzo J.A., Hammond G.L., et al. What is the appropriate size criterion for resection of thoracic aortic aneurysms?. J Thorac Cardiovasc Surg 1997;113:476-491.[Abstract/Free Full Text]
-
Milano A., Pratali S., De Carlo M., Borzoni G., Tartarini G., Bortolotti U. Ascending aorta dissection after aortic valve replacement. J Heart Valve Dis 1998;7:75-80.[Medline]
-
McDonald M.L., Smedira N.G., Blackstone E.H., Grimm R.A., Lytle B.W., Cosgrove D.M. Reduced survival in women after valve surgery for aortic regurgitation: effect of aortic enlargement and late aortic rupture. J Thorac Cardiovasc Surg 2000;119:1205-1215.[Abstract/Free Full Text]
-
Girardi L.N., Talwalkar N.G., Coselli J.S. Aortic root replacement: results using the St. Jude Medical/Hemashield Composite Graft. Ann Thorac Surg 1997;64:1032-1035.[Abstract/Free Full Text]
-
Langley S.M., Rooney S.J., Dalrymple-Hay M.J.R., et al. Replacement of the proximal aorta and aortic valve using a composite bileaflet prosthesis and gelatin-impregnated polyester graft (Carbo-Seal): early results in 143 patients. J Thorac Cardiovasc Surg 1999;118:1014-1020.[Abstract/Free Full Text]
-
Luciani G.B., Casali G., Barozzi L., Mazzucco A. Aortic root replacement with the CarboSeal composite graft: 7-Year experience with the first 100 implants. Ann Thorac Surg 1999;68:2258-2262.[Abstract/Free Full Text]
-
Fiane A.E., Geiran O.R., Svennevig J.L. Up to eight years follow-up of 997 patients receiving the CarboMedics prosthetic heart valve. Ann Thorac Surg 1998;66:443-448.[Abstract/Free Full Text]
-
Bernal J.M., Rabasa J.M., Gutierrez-Garcia F., Morales C., Nistal J.F., Revuelta J.M. The CarboMedics valve: experience with 1049 implants. Ann Thorac Surg 1998;65:137-143.[Abstract/Free Full Text]
This article has been cited by other articles:
|
|
|
|
 
P. P. Urbanski
Valve-Sparing Aortic Root Repair With Patch Technique
Ann. Thorac. Surg.,
September 1, 2005;
80(3):
839 - 843.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
P. P. Urbanski, A. Diegeler, A. Siebel, M. Zacher, and R. W. Hacker
Valved stentless composite graft: clinical outcomes and hemodynamic characteristics
Ann. Thorac. Surg.,
February 1, 2003;
75(2):
467 - 471.
[Abstract]
[Full Text]
[PDF]
|
|
|
Top
Abstract
Introduction
