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Ann Thorac Surg 2005;80:488-494
© 2005 The Society of Thoracic Surgeons
a Cardiothoracic Centre, All India Institute of Medical Sciences, New Delhi, India
b Department of Biostatistics, All India Institute of Medical Sciences, New Delhi, India
Accepted for publication March 4, 2005.
* Address reprint requests to Dr Kumar, Department of Cardiothoracic and Vascular Surgery, Cardiothoracic Centre, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, 110 029 India (Email: asampath_kumar{at}hotmail.com).
| Abstract |
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METHODS: From October 1993 through September 2003, 153 patients with aortic valve disease (81 rheumatic and 72 non-rheumatic), with a mean age of 28 ± 14.2 years underwent the Ross procedure with root replacement technique and right ventricular outflow tract reconstruction using a homograft. Associated procedures included mitral valve repair (n = 19), open mitral commissurotomy (n = 15), tricuspid valve repair (n = 2), homograft mitral valve replacement (n = 2), and subaortic membrane resection (n = 1).
RESULTS: Early mortality was 6.5% (10 patients). Mean follow-up was 77 ± 42 months (range, 7 to 132 months; median, 90 months). One hundred, twenty-one survivors (84.6%) had no significant aortic regurgitation. Reoperation was required in 10 patients for autograft dysfunction alone (n = 3), infective endocarditis (n = 2), autograft dysfunction with failed mitral valve repair (n = 3), and failed mitral valve repair alone (n = 2). No reoperations were required for the pulmonary homograft. There were 8 late deaths. Actuarial and reoperation-free survival at 90 months were 91.% ± 3.5%, 95.3% ± 2.7%, in non-rheumatics and 86.1 ± 3.9%, 90.5 ± 3.7% in rheumatics, respectively. Freedom from significant aortic stenosis or regurgitation was 91.5 ± 2.8% in non-rheumatics and 80.6 ± 4.8% in rheumatics. Event-free survival was 86.2 ± 4.9% in non-rheumatics and only 68.9 ± 5.3% in rheumatics.
CONCLUSIONS: The Ross procedure is not recommended for young patients (< 30 years) with rheumatic heart disease. It provides satisfactory hemodynamic and clinical results in properly selected patients. Important autograft dilatation was not observed in our patients.
| Introduction |
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| Patients and Methods |
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The surgical procedure has been described in detail earlier by us [5, 10, 11]. Root replacement technique with coronary artery implantation was used in all patients. The left coronary artery was not implanted as a button. Instead, the left coronary ostium was left attached to a tongue of the distal aortic wall. Right ventricle-pulmonary artery continuity was restored using an antibiotic preserved (n = 47) or cryopreserved homograft (n = 106) obtained from our own tissue valve bank. A pulmonary homograft was used in 151 patients and aortic homograft in 2 patients. Associated procedures included mitral valve repair (n = 19), open mitral commissurotomy (n = 15), tricuspid valve repair (n = 2), homograft mitral valve replacement (n = 2), and subaortic membrane resection (n = 1) using techniques described earlier by us [12]. For the isolated Ross procedure, the mean aortic cross-clamp and cardiopulmonary bypass times were 121.4 ± 19.4 minutes (range, 81 to 197 min) and 153 ± 24.7 minutes (range, 121 to 226 min), respectively. When the mitral valve procedure was done concomitantly, these increased to 135 ± 31 minutes (109 to 230 min) and 168 ± 32 minutes (140 to 280 min), respectively.
After weaning from cardiopulmonary bypass, transesophageal echocardiography was performed in all patients to confirm normal autograft function and to assess associated procedures. Prior to discharge from the hospital, transthoracic echocardiography was performed in all patients, and this was repeated every 6 months. Aortic regurgitation (AR) was assessed on a scale of +1 to +4 according to published criteria [13]. Aortic regurgitation with a grade of +1 was considered mild. Peak gradients less than 25 mm Hg across the aortic valve were considered as mild aortic stenosis and
50 mm Hg was considered significant aortic stenosis.
No anticoagulants or anti-platelet drugs were prescribed. Long-acting benzathine penicillin 3 weekly was prescribed to all patients less than 45 years of age with rheumatic heart disease. All patients received itraconazole for 6 weeks after surgery as prophylaxis against fungal endocarditis.
| Statistical Analysis |
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| Results |
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Early Reoperation
Six patients required reoperation for excessive mediastinal bleeding. Four of these were in the first 12 patients in which the bleeding was from the raw surface of the posterior wall of the right ventricular outflow tract. In the other 2 patients, the source of bleeding was not related to the suture lines. One patient required reoperation within a month for fungal endocarditis of the autograft, and she died after surgery from multiorgan dysfunction.
Early Autograft Function
In all patients, intraoperative transesophageal echocardiography revealed trivial or no aortic regurgitation. Three patients had mild mitral regurgitation. Transthoracic echocardiography prior to discharge from the hospital showed mild AR in 1 patient.
Follow-Up
All patients were seen in the outpatient clinic at 6-month intervals and underwent clinical examination and echocardiography. Between January 2004 and September 2004, the records of 140 of the 143 survivors were obtained, and their last follow-up during this period was taken to report the results. The follow-up data (97.9% complete) ranged from 7 to 132 months (mean, 77 ± 42 months; median, 90 months) and totaled 917.6 patient-years. Among survivors, 20 patients (14%) were followed-up for 10 or more years, 62 (43.4%) were followed-up for 7 or more years, 12 (8.4%) for more than 5 years, 24 (16.8%) for more than 3 years, and 6 (4.2%) for more than 2 years.
Thromboembolism
There were no thromboembolic complications in the survivors.
Hemolysis
Four patients had significant hemolysis. In the first 3 patients this was associated with excessive mediastinal bleeding, disseminated intravascular coagulation, and early death. In the fourth patient, this was associated with mild mitral regurgitation and subsided gradually. The incidence of this complication in survivors was 0.1 event per 100 patient-years of follow-up.
Infective Endocarditis
Five patients had infective endocarditis (0.4 events per 100 patient-years) develop. This was fungal in 3 patients and bacterial in 2. One patient with fungal endocarditis died within 1 month of surgery, the other 2 underwent homograft aortic valve replacement 3 and 4 months after the initial operation and died. The 2 patients with bacterial endocarditis died 9 and 13 months after operation.
Late Autograft Function
At last follow-up between January 2004 and September 2004, transthoracic echocardiography showed no aortic regurgitation in 121 patients (84.6%). Nineteen patients had significant aortic regurgitation (2 events per 100 patient-years). Moderate (n = 14) to severe (n = 5) aortic regurgitation was noted in 19 patients (13.3%) of the 143 survivors at a median follow-up of 90 months after operation. Fifteen of these patients had rheumatic heart disease, were young (< 30 years of age), and had significant AR develop 57.6 ± 36.2 months after the operation; five of these patients had evidence of recurrent attacks of rheumatic fever and had significant AR develop within 2 years of operation. Two of these (patients 1 and 5, Table 2) had stopped penicillin prophylaxis and required hospitalization for recurrent attacks of acute rheumatic fever.
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At 90 months, freedom from autograft dysfunction was 84.3 ± 3.6 % (95% CI 77.3 to 91.3) for the entire group; in rheumatics it was 80.6 ± 4.8% (95% CI 71.2 to 90) as compared with 91.5 ± 2.8% (95% CI 86 to 97) in non-rheumatic group (log rank test, 1.9; p = 0.16). At 10 years, it was 79.2 ± 4.9 % (95% CI 69.8 to 88.6) for the entire group; in rheumatics it was 74.7 ± 6.1% (95% CI 62.7 to 86.7) as compared with 91.5 ± 2.8% (95% CI 86 to 97) in the non-rheumatic group (Fig 1).
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Late Reoperation
Late reoperation (Table 2) was required in 10 patients (1.1 events per 100 patient-years) after a mean period of 34.5 ± 31.9 months (range, 3 to 108 months). Two patients required operation for fungal endocarditis 3 and 4 months after surgery. In both these patients the autograft was explanted and replaced with a cryopreserved aortic homograft. Both these patients died. Two patients required reoperation for failed mitral valve repair with normal neoaortic valve function. The first of these 2 patients underwent homograft mitral valve replacement 26 months after the initial operation; however she died 3 months later. The other patient underwent mechanical mitral valve replacement 31 months after initial operation. Three patients required mechanical double valve replacement for autograft failure and failure of associated mitral valve repair 12 and 48 months (2 patients) after initial operation. Two patients with severe aortic regurgitation in the rheumatic group underwent aortic valve replacement with a mechanical prosthesis 56 and 108 months after initial operation. The last patient, an 11-year-old boy required mechanical aortic valve replacement for autograft failure secondary to a perforation in the autograft cusps, which was probably due to endocarditis. In this patient, repair of the autograft and homograft aortic valve replacement was not performed at the patients request.
In patients undergoing reoperation other than for endocarditis, the geometry of the aortic sinuses was maintained. The autograft cusps showed thickening, retraction, and failure of coaptation without any prolapse or commissural fusion. Besides this, the aortic root was dilated at reoperation in 2 patients in the rheumatic group. In the rheumatic group, the histology of explanted autografts revealed valve thickening, fibrosis, active chronic inflammation with small vessel, and intimal proliferation. This has been described in detail in our prior publication [10].
At 90 months, freedom from reoperation was 91.8 ± 2.7 % (95% CI 86.5 to 97.1) for the entire group; in rheumatics it was 90.5 ± 3.7 % (95% CI 83.2 to 97.8) as compared with 95.3 ± 2.7% (95% CI 90 to 100) in non-rheumatics. At 10 years, it was 86 ± 6.1 % (95% CI 74 to 97.9) for the entire group; in rheumatics it was 76.24 ± 12.4% (95% CI 52.7 to 99.6) compared with 95.3 ± 2.7% (95% CI 90 to 100) in non-rheumatics (log rank test, 1.06; p = 0.30) (Fig 2).
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At 90 months, the actuarial survival was 88.3 ± 2.7% (95% CI 83 to 93.6) for the entire group; in rheumatics it was 86.1 ± 3.9% (95% CI 78.5 to 93.7) compared with 91 ± 3.5% (95% CI 84.1 to 97.9) in non-rheumatics. At 10 years, it was 86.9 ± 2.9% (95% CI 81.2 to 92.6) for the entire group; in rheumatics it was 84.5 ± 4.1% (95% CI 76.5 to 92.5) compared with 91 ± 3.5% (95% CI 84.1 to 97.9) in non-rheumatics (log rank test, 0.89; p = 0.34) (Fig 3).
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| Comment |
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There has been no consensus on the best technique of autograft implantation. Ross used the scalloped subcoronary technique with good results [16], whereas Elkins and colleagues [17] used the aortic root inclusion and root replacement technique. The subcoronary technique is now rarely used as it is more complex, especially in the asymmetrical annulus, and there is a higher incidence of autograft insufficiency and reoperation [5, 18]. The cylinder inclusion technique carries a higher incidence of autograft obstruction and distortion of coronary anastomosis because of a blood-filling space between the autograft and the native aortic wall [18, 19]. We believe that when the autograft is fixed to the relatively dense collagen structure of the aortic annulus with the root replacement technique, the distortion of the commissures is avoided, which leads to better autograft function in the mid-term. Also the asymmetry of the native aorta in bicuspid aortic valves can be ignored with this technique.
There have been concerns with the use of root replacement technique in patients with bicuspid aortic valve disease as it predisposes to autograft dilatation leading to progressive aortic regurgitation [20]. Some have reported that this autograft dilatation is likely to occur if the autograft is implanted in a dilated aortic annulus [2022]. We have not observed important autograft dilatation in patients with a bicuspid aortic valve and also in the majority of the rheumatics. We do not perform this operation if the aortic annulus measures 30 mm or more on transesophageal echocardiography. In addition, a strip of pericardium was used in all adults to buttress the proximal suture line, and the autograft annulus was seated in the exact position of the native aortic valve annulus. However, autograft dilatation was observed in 2 young patients with rheumatic aortic valve disease, which was due to recurrent attacks of rheumatic activity and is consistent with our earlier observation that the pulmonary autograft is best avoided in this subset of patients [10].
Reoperation for autograft dysfunction has been a major concern [49]. This may be due to technical factors, especially in the learning curve, progressive AR due to non-coaptation of the leaflets, or pulmonary autograft to aortic annulus mismatch. The major reason for reoperation in this group of patients was our enthusiastic use of the Ross procedure in the young rheumatic hoping for a cure. The observation of rheumatic valvulitis of the autograft on histology [10] in addition to the failed mitral valve procedures were the main reasons for abandoning this operation in young rheumatics and also in patients with associated mitral valve disease. Since 1998, we offer the Ross procedure for older patients (> 30 years) with rheumatic heart disease only if they have isolated aortic valve disease.
Freedom from reoperation in our series was more than 80% in the entire group and 95% in non-rheumatics. These results compare favorably with Rosss own results in which 85% and 61% of the hospital survivors were free of reoperation 10 and 20 years, respectively, after the initial operation [6].
The freedom from reoperation on the pulmonary homograft was 100% at 10 years in our patients and has ranged from 80% to 86% in various series [49]. We believe that the cryopreserved pulmonary homograft offers the best freedom from reoperation. We have not used other commercially available substitutes. The higher age of our patients, along with less number of children, may also be a possible reason for none of our patients requiring reoperation for pulmonary homograft dysfunction.
Our early mortality of 6.5% is higher than the early mortality of 3.3% from the International Registry for the Ross procedure [23]. However, the early deaths in our series were predominantly in the early part of our experience. In the last 100 consecutive patients we have had only 3 early deaths. Therefore, although the Ross procedure may carry a higher mortality than a standard prosthetic aortic valve replacement, the results become fairly standardized after the learning curve is over. We did have a higher incidence of endocarditis in our patients, which was probably related to environmental factors due to unsatisfactory air conditioning. This problem has now been eliminated.
One of the limitations of this study is that the actuarial probabilities are reported at either a median follow-up of 90 months or at 10 years using the Kaplan-Meier analysis. Calculating freedom from valve-related events in this manner may overestimate the truly occurring probabilities. However these are overcome to an extent by providing linearized rates. Also we had 10 patients with moderate aortic regurgitation and 4 with pulmonary homograft dysfunction who have not undergone reoperation yet because of having no change in the functional class. Although these patients have been included for the purpose of estimating the actuarial freedom from autograft dysfunction, they have not been included for calculating the reoperation-free survival. These patients are being closely followed.
We now do not perform the Ross procedure in young rheumatics (< 30 years) and we do offer it to older patients (> 30 years) with rheumatic heart disease only if they have isolated aortic valve disease. In patients with non-rheumatic causes, the procedure is only performed if the aortic root size is 30 mm or less. It is not performed in patients requiring emergency surgery, significant left ventricular dysfunction, mitral valve disease requiring prosthetic valve replacement, and patients who have bicuspid pulmonary valve or pulmonary regurgitation. Proper patient selection has improved our results and helped us achieve better survival and autograft function.
| Conclusion |
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| References |
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This article has been cited by other articles:
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A. S. Kumar, S. Talwar, and A. Gupta Mitral valve replacement with the pulmonary autograft: midterm results. J. Thorac. Cardiovasc. Surg., August 1, 2009; 138(2): 359 - 364. [Abstract] [Full Text] [PDF] |
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J. J.M. Takkenberg, L. M.A. Klieverik, P. H. Schoof, R.-J. van Suylen, L. A. van Herwerden, P. E. Zondervan, J. W. Roos-Hesselink, M. J.C. Eijkemans, M. H. Yacoub, and A. J.J.C. Bogers The Ross Procedure: A Systematic Review and Meta-Analysis Circulation, January 20, 2009; 119(2): 222 - 228. [Abstract] [Full Text] [PDF] |
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V Chaturvedi, S Talwar, B Airan, and B Bhargava Interventional cardiology and cardiac surgery in India Heart, March 1, 2008; 94(3): 268 - 274. [Abstract] [Full Text] [PDF] |
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