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Mitral stenosis after mitral valve repair for non-rheumatic mitral regurgitation
Mitral Stenosis After Mitral Valve Repair for NonRheumatic Mitral Regurgitation Mohamed F. Ibrahim, MD, and Tirone E. David, MD Division of Cardiovascular Surgery, Toronto General Hospital and University of Toronto, Toronto, Ontario, Canada
Background. Mitral stenosis after mitral valve repair for non-rheumatic mitral regurgitation is rare. Methods. From 1990 to 1999, 478 patients had mitral valve repair for myxomatous and 40 patients had mitral valve repair for ischemic mitral regurgitation. The Carpentier annuloplasty ring (Edwards Lifesciences, Irvine, CA) was used in 72 patients, the Duran ring (Medtronic, Minneapolis, MN) in 152, a posterior band in 221 and no ring or band in 73 patients. Results. Four patients developed mitral stenosis late after mitral valve repair: 2 for myxomatous disease and 2 for ischemic mitral regurgitation. All 4 patients had Duran annuloplasty rings (sizes 25 to 31). The diagnosis of mitral stenosis was made by Doppler echocardiography. The mitral valve area in these 4 patients decreased from 2.7 cm2 (range, 2.3 to 3.2 cm2) early postoperatively
to 0.85 cm2 (0.4 to 1.2 cm2) after a mean follow-up of 66 months (range, 38 to 110 months). Three patients had mitral valve replacement and the etiology of the mitral stenosis was the same in all patients (ie, pannus overgrowth on the annuloplasty ring with extension onto both leaflets rendering them stiff and immobile). The fourth patient had a mitral valve area of 1.2 cm2, which was mildly symptomatic with normal pulmonary artery pressure, and this patient has not had reoperation. Conclusions. Mitral stenosis may develop after mitral valve repair for myxomatous disease or ischemic mitral regurgitation when a Duran ring is used for annuloplasty. The stenosis is caused by pannus on the annuloplasty ring with extension onto the leaflets. (Ann Thorac Surg 2002;73:34 – 6) © 2002 by The Society of Thoracic Surgeons
R
outcomes of patients with myxomatous mitral valve disease have been described elsewhere [3– 4].
ecurrent mitral regurgitation is the most common cause of failure of mitral valve repair for nonrheumatic mitral regurgitation. Mitral stenosis is rare after mitral repair for correction of mitral regurgitation caused by myxomatous disease or ischemic mitral valve disease. Prosthetic mitral valve stenosis caused by thrombosis or pannus formation is a well-recognized complication of mitral valve replacement [1–2]. However, we could not find any report on mitral stenosis after mitral valve repair for non-rheumatic mitral regurgitation. This study describes 4 patients who had mitral stenosis after mitral valve repair for myxomatous disease or ischemic mitral regurgitation.
Patients and Methods From January 1990 to December 1999, 478 patients with myxomatous disease and 40 with ischemic mitral regurgitation (MR) underwent mitral valve repair by one of us (TED). These patients have been followed-up by their referring cardiologists and contacted by our research personnel periodically. Multiple Doppler echocardiographic studies were performed intraoperatively, before hospital discharge, and annually thereafter. Follow-up extended from 12 to 127 months (mean, 49 ⫾ 33 months). Only 3 patients were lost to follow-up. The clinical Accepted for publication Sept 5, 2001. Address reprint requests to Dr David, 200 Elizabeth St–13EN219, Toronto, Ontario M5G 2C4, Canada; e-mail: [email protected].
© 2002 by The Society of Thoracic Surgeons Published by Elsevier Science Inc
Results Mitral annuloplasty with a ring or posterior band was performed in 405 patients with myxomatous MR; the Carpentier ring (Edwards Lifesciences, Irvine, CA) was used in 72 patients, the Duran ring (Medtronic, Minneapolis, MN) in 138, and a custom-made posterior band or a Cosgrove-Edwards band (Edwards Lifesciences, Irvine, CA) in 195. The remaining 73 patients with myxomatous MR had mitral valve repair without an annuloplasty ring or band. All patients with ischemic MR had an annuloplasty (14 patients with the Duran ring and 26 with a posterior band). The custom-made band is made with a double velour Dacron fabric. The duration of follow-up for patients with various types of annuloplasty were different (ie, 85 ⫾ 99 months for the Carpentier ring; 59 ⫾ 21 months for the Duran ring; and 30 ⫾ 29 months for the posterior band (p ⫽ 0.005). Four patients, 2 with myxomatous disease and 2 with ischemic MR had progressive mitral stenosis at the follow-up. The mitral valve repair in 2 patients with myxomatous degeneration consisted of the resection of central portion of the posterior leaflet and annuloplasty with a Duran ring. The mitral valve repair in the 2 patients with ischemic MR consisted of a simple reduction of the posterior mitral annulus with a Duran ring. Table 1 shows the clinical profile of these 4 patients. Three of them required mitral valve replacement because 0003-4975/02/$22.00 PII S0003-4975(01)03305-7
Ann Thorac Surg 2002;73:34 – 6
IBRAHIM AND DAVID MITRAL STENOSIS AFTER MITRAL VALVE REPAIR
35
Table 1. Clinical Profile of Patients With Mitral Stenosis
Age at first surgery (y) Sex Mitral valve pathology Coronary artery bypass graft Annuloplasty ring Date of mitral valve repair (mo/y) Early mitral valve area (cm2) Late mitral valve area (cm2) Symptoms Date of reoperation (mo/y) Mitral valve replacement (type/size) Follow-up NYHA CEP ⫽ Carpentier-Edwards pericardial;
Patient 1
Patient 2
55 Male Myxomatous No Duran 29 8/90 3.2 1.0 Shortness of breath/fatigue 1/96 St. Jude 29 Class II
58 Male Myxomatous No Duran 31 6/93 2.8 0.8 Transient ischemic attack/stroke 3/97 Hancock II 31 Class II
Patient 3
Patient 4
61
51 Male Ischemic Yes Duran 27 5/90 2.5 1.2 Fatigue
Female Ischemic Yes Duran 25 4/91 2.3 0.4 Shortness of breath/ congestive heart failure 6/00 CEP 27 Class I
None None Class II
NYHA ⫽ New York Heart Association.
of severe symptoms. The intraoperative findings were identical in all patients ie, dense fibrous tissue covered the annuloplasty ring and extended onto both leaflets of the mitral valve narrowing its orifice and rendering the leaflets stiff and immobile. The chordae tendineae were not affected by the pannus. Figure 1 shows an intraoperative photograph of the mitral valve in the first patient listed on Table 1. The pannus covering the mitral valve could not be stripped off without damaging the leaflets in any of the 3 patients and mitral valve replacement was necessary. A bioprosthetic mitral valve was used in 2 patients and a mechanical valve in one. Pathologic examination revealed no chordal fusion, shortening, or fibrosis, but the atrial side of the leaflets were thickened with signs of chronic inflammation that appeared to be originating from the annuloplasty ring. All 3 patients survived reoperation without serious complications. They continue to be monitored with annual echocardiographic studies and thus far none have developed prosthetic mitral valve stenosis. One patient developed prosthetic mitral valve endocarditis 4 years postoperatively and was successfully treated with antibiotics alone. The fourth patient had a mitral valve area of 2.5 cm2
Fig 1. Intraoperative appearance of a stenotic mitral valve after repair for mitral regurgitation caused by myxomatous disease.
early postoperatively, which decreased to 1.2 cm2 by the third postoperative year and has not progressed any further. This patient has mild symptoms, a normal pulmonary artery pressure, and has not had a need for further reoperation.
Comment Two inflammatory processes with common mechanisms and manifestations develop after implantation of a cardiac prosthesis [5]. The first is reparatory in nature and involves the replacement of damaged tissues around the valve annulus with nonspecialized connective tissue. The second is the foreign-body type reaction to synthetic material, a special form of nonimmune inflammation. The prolonged exposure to the nondegradable synthetic material presents a persistent stimulus to macrophage infiltration and the proliferation of fibroblasts, both phenomena typical of chronic inflammation. In this reaction, the most prominent cells are macrophages that are grouped as giant cells. The presence of these cells is indicative of severe reaction in which the material is not well tolerated and those cells are presumably attempting phagocytosis of the material. This is likely the mechanism of prosthetic valve stenosis caused by pannus [1–2]. The development of late mitral stenosis after mitral valve repair for rheumatic mitral valve disease is common [6 –7], however, it has not been described after mitral valve repair for myxomatous disease or ischemic MR. Recurrent MR is the usual cause of failure after repair for myxomatous disease or ischemic mitral valve disease [3– 4, 8 –9]. The 4 patients described in this study had mitral annuloplasty with the Duran ring as part of the mitral valve repair. We have not found this complication in patients who had mitral annuloplasty with the Carpentier ring or with a posterior annuloplasty band. The duration of follow-up in patients with the Carpentier ring was longer than those with the Duran ring, but there were only one-half as many patients at risk in the first group. We have not encountered this complication after annuloplasty with a custom-made posterior band or the Cosgrove-Edwards band, but the dura-
36
IBRAHIM AND DAVID MITRAL STENOSIS AFTER MITRAL VALVE REPAIR
tion of follow-up was significantly shorter than with the Duran ring. Because this is a rare complication of mitral valve repair and our sample sizes are relatively small, it is not possible to determine if it is the Duran ring, the patient, or both that caused the excessive pannus on the ring and mitral valve leaflets. In summary, mitral stenosis after mitral valve repair for myxomatous disease or ischemic MR may occur because of pannus overgrowth on a Duran annuloplasty ring.
Ann Thorac Surg 2002;73:34 – 6
4.
5.
6. 7.
References 1. Bortolotti U, Galluci V, Casoratto D, Thiene G. Fibrous tissue overgrowth on Hancock mitral xenografts. A cause of late prosthetic stenosis. Cardiovasc Surg 1979;27:316– 8. 2. Munclinger MJ, Patel JJ, Mitha AS. Thrombolysis of thrombosed St. Jude Medical prosthetic valves: rethrombosis–a sign of tissue ingrowth. J Thorac Cardiovasc Surg 1998;115:248–9. 3. David TE, Armstrong S, Sun Z, Daniel L. Late results of mitral
8. 9.
valve repair for mitral regurgitation due to degenerative disease. Ann Thorac Surg 1993;56:7–14. David TE, Omran A, Armstrong S, et al. Long-term results of mitral valve repair for myxomatous disease with, and without chordal replacement with expanded polytetrafluoroethylene sutures. J Thorac Cardiovasc Surg 1998;115:1279– 86. Schoen EJ. General pathologic considerations. In: Schoen FJ, ed. Interventional and surgical cardiovascular pathology: clinical correlations and basic principles. Philadelphia: WB Saunders Company, 1989:1–58. Fernandez J, Joyce DH, Hirschefeld K, et al. Factors affecting mitral valver reoperation in 317 survivors after mitral valve reconstruction. Ann Thorac Surg 1992;54:440– 8. Yau TM, El-Ghoneimi YAF, Armstrong S, Ivanov J, David TE. Mitral valve repair and replacement for rheumatic disease. J Thorac Cardiovasc Surg 2000;119:53– 61. Gillinov AM, Cosgrove DM, Blackstone EH, et al. Durability of mitral valve repair for degenerative disease. J Thorac Cardiovasc Surg 1998;116:734– 43. Cohn LH, Couper GS, Aranki SF, Rizzo RJ, Kinchla NM, Collins JJ Jr. Long-term results of mitral valve reconstruction for regurgitation of the myxomatous mitral valve. J Thorac Cardiovasc Surg 1994;107:143–51.
Background. Mitral stenosis after mitral valve repair for non-rheumatic mitral regurgitation is rare. Methods. From 1990 to 1999, 478 patients had mitral valve repair for myxomatous and 40 patients had mitral valve repair for ischemic mitral regurgitation. The Carpentier annuloplasty ring (Edwards Lifesciences, Irvine, CA) was used in 72 patients, the Duran ring (Medtronic, Minneapolis, MN) in 152, a posterior band in 221 and no ring or band in 73 patients. Results. Four patients developed mitral stenosis late after mitral valve repair: 2 for myxomatous disease and 2 for ischemic mitral regurgitation. All 4 patients had Duran annuloplasty rings (sizes 25 to 31). The diagnosis of mitral stenosis was made by Doppler echocardiography. The mitral valve area in these 4 patients decreased from 2.7 cm2 (range, 2.3 to 3.2 cm2) early postoperatively
to 0.85 cm2 (0.4 to 1.2 cm2) after a mean follow-up of 66 months (range, 38 to 110 months). Three patients had mitral valve replacement and the etiology of the mitral stenosis was the same in all patients (ie, pannus overgrowth on the annuloplasty ring with extension onto both leaflets rendering them stiff and immobile). The fourth patient had a mitral valve area of 1.2 cm2, which was mildly symptomatic with normal pulmonary artery pressure, and this patient has not had reoperation. Conclusions. Mitral stenosis may develop after mitral valve repair for myxomatous disease or ischemic mitral regurgitation when a Duran ring is used for annuloplasty. The stenosis is caused by pannus on the annuloplasty ring with extension onto the leaflets. (Ann Thorac Surg 2002;73:34 – 6) © 2002 by The Society of Thoracic Surgeons
R
outcomes of patients with myxomatous mitral valve disease have been described elsewhere [3– 4].
ecurrent mitral regurgitation is the most common cause of failure of mitral valve repair for nonrheumatic mitral regurgitation. Mitral stenosis is rare after mitral repair for correction of mitral regurgitation caused by myxomatous disease or ischemic mitral valve disease. Prosthetic mitral valve stenosis caused by thrombosis or pannus formation is a well-recognized complication of mitral valve replacement [1–2]. However, we could not find any report on mitral stenosis after mitral valve repair for non-rheumatic mitral regurgitation. This study describes 4 patients who had mitral stenosis after mitral valve repair for myxomatous disease or ischemic mitral regurgitation.
Patients and Methods From January 1990 to December 1999, 478 patients with myxomatous disease and 40 with ischemic mitral regurgitation (MR) underwent mitral valve repair by one of us (TED). These patients have been followed-up by their referring cardiologists and contacted by our research personnel periodically. Multiple Doppler echocardiographic studies were performed intraoperatively, before hospital discharge, and annually thereafter. Follow-up extended from 12 to 127 months (mean, 49 ⫾ 33 months). Only 3 patients were lost to follow-up. The clinical Accepted for publication Sept 5, 2001. Address reprint requests to Dr David, 200 Elizabeth St–13EN219, Toronto, Ontario M5G 2C4, Canada; e-mail: [email protected].
© 2002 by The Society of Thoracic Surgeons Published by Elsevier Science Inc
Results Mitral annuloplasty with a ring or posterior band was performed in 405 patients with myxomatous MR; the Carpentier ring (Edwards Lifesciences, Irvine, CA) was used in 72 patients, the Duran ring (Medtronic, Minneapolis, MN) in 138, and a custom-made posterior band or a Cosgrove-Edwards band (Edwards Lifesciences, Irvine, CA) in 195. The remaining 73 patients with myxomatous MR had mitral valve repair without an annuloplasty ring or band. All patients with ischemic MR had an annuloplasty (14 patients with the Duran ring and 26 with a posterior band). The custom-made band is made with a double velour Dacron fabric. The duration of follow-up for patients with various types of annuloplasty were different (ie, 85 ⫾ 99 months for the Carpentier ring; 59 ⫾ 21 months for the Duran ring; and 30 ⫾ 29 months for the posterior band (p ⫽ 0.005). Four patients, 2 with myxomatous disease and 2 with ischemic MR had progressive mitral stenosis at the follow-up. The mitral valve repair in 2 patients with myxomatous degeneration consisted of the resection of central portion of the posterior leaflet and annuloplasty with a Duran ring. The mitral valve repair in the 2 patients with ischemic MR consisted of a simple reduction of the posterior mitral annulus with a Duran ring. Table 1 shows the clinical profile of these 4 patients. Three of them required mitral valve replacement because 0003-4975/02/$22.00 PII S0003-4975(01)03305-7
Ann Thorac Surg 2002;73:34 – 6
IBRAHIM AND DAVID MITRAL STENOSIS AFTER MITRAL VALVE REPAIR
35
Table 1. Clinical Profile of Patients With Mitral Stenosis
Age at first surgery (y) Sex Mitral valve pathology Coronary artery bypass graft Annuloplasty ring Date of mitral valve repair (mo/y) Early mitral valve area (cm2) Late mitral valve area (cm2) Symptoms Date of reoperation (mo/y) Mitral valve replacement (type/size) Follow-up NYHA CEP ⫽ Carpentier-Edwards pericardial;
Patient 1
Patient 2
55 Male Myxomatous No Duran 29 8/90 3.2 1.0 Shortness of breath/fatigue 1/96 St. Jude 29 Class II
58 Male Myxomatous No Duran 31 6/93 2.8 0.8 Transient ischemic attack/stroke 3/97 Hancock II 31 Class II
Patient 3
Patient 4
61
51 Male Ischemic Yes Duran 27 5/90 2.5 1.2 Fatigue
Female Ischemic Yes Duran 25 4/91 2.3 0.4 Shortness of breath/ congestive heart failure 6/00 CEP 27 Class I
None None Class II
NYHA ⫽ New York Heart Association.
of severe symptoms. The intraoperative findings were identical in all patients ie, dense fibrous tissue covered the annuloplasty ring and extended onto both leaflets of the mitral valve narrowing its orifice and rendering the leaflets stiff and immobile. The chordae tendineae were not affected by the pannus. Figure 1 shows an intraoperative photograph of the mitral valve in the first patient listed on Table 1. The pannus covering the mitral valve could not be stripped off without damaging the leaflets in any of the 3 patients and mitral valve replacement was necessary. A bioprosthetic mitral valve was used in 2 patients and a mechanical valve in one. Pathologic examination revealed no chordal fusion, shortening, or fibrosis, but the atrial side of the leaflets were thickened with signs of chronic inflammation that appeared to be originating from the annuloplasty ring. All 3 patients survived reoperation without serious complications. They continue to be monitored with annual echocardiographic studies and thus far none have developed prosthetic mitral valve stenosis. One patient developed prosthetic mitral valve endocarditis 4 years postoperatively and was successfully treated with antibiotics alone. The fourth patient had a mitral valve area of 2.5 cm2
Fig 1. Intraoperative appearance of a stenotic mitral valve after repair for mitral regurgitation caused by myxomatous disease.
early postoperatively, which decreased to 1.2 cm2 by the third postoperative year and has not progressed any further. This patient has mild symptoms, a normal pulmonary artery pressure, and has not had a need for further reoperation.
Comment Two inflammatory processes with common mechanisms and manifestations develop after implantation of a cardiac prosthesis [5]. The first is reparatory in nature and involves the replacement of damaged tissues around the valve annulus with nonspecialized connective tissue. The second is the foreign-body type reaction to synthetic material, a special form of nonimmune inflammation. The prolonged exposure to the nondegradable synthetic material presents a persistent stimulus to macrophage infiltration and the proliferation of fibroblasts, both phenomena typical of chronic inflammation. In this reaction, the most prominent cells are macrophages that are grouped as giant cells. The presence of these cells is indicative of severe reaction in which the material is not well tolerated and those cells are presumably attempting phagocytosis of the material. This is likely the mechanism of prosthetic valve stenosis caused by pannus [1–2]. The development of late mitral stenosis after mitral valve repair for rheumatic mitral valve disease is common [6 –7], however, it has not been described after mitral valve repair for myxomatous disease or ischemic MR. Recurrent MR is the usual cause of failure after repair for myxomatous disease or ischemic mitral valve disease [3– 4, 8 –9]. The 4 patients described in this study had mitral annuloplasty with the Duran ring as part of the mitral valve repair. We have not found this complication in patients who had mitral annuloplasty with the Carpentier ring or with a posterior annuloplasty band. The duration of follow-up in patients with the Carpentier ring was longer than those with the Duran ring, but there were only one-half as many patients at risk in the first group. We have not encountered this complication after annuloplasty with a custom-made posterior band or the Cosgrove-Edwards band, but the dura-
36
IBRAHIM AND DAVID MITRAL STENOSIS AFTER MITRAL VALVE REPAIR
tion of follow-up was significantly shorter than with the Duran ring. Because this is a rare complication of mitral valve repair and our sample sizes are relatively small, it is not possible to determine if it is the Duran ring, the patient, or both that caused the excessive pannus on the ring and mitral valve leaflets. In summary, mitral stenosis after mitral valve repair for myxomatous disease or ischemic MR may occur because of pannus overgrowth on a Duran annuloplasty ring.
Ann Thorac Surg 2002;73:34 – 6
4.
5.
6. 7.
References 1. Bortolotti U, Galluci V, Casoratto D, Thiene G. Fibrous tissue overgrowth on Hancock mitral xenografts. A cause of late prosthetic stenosis. Cardiovasc Surg 1979;27:316– 8. 2. Munclinger MJ, Patel JJ, Mitha AS. Thrombolysis of thrombosed St. Jude Medical prosthetic valves: rethrombosis–a sign of tissue ingrowth. J Thorac Cardiovasc Surg 1998;115:248–9. 3. David TE, Armstrong S, Sun Z, Daniel L. Late results of mitral
8. 9.
valve repair for mitral regurgitation due to degenerative disease. Ann Thorac Surg 1993;56:7–14. David TE, Omran A, Armstrong S, et al. Long-term results of mitral valve repair for myxomatous disease with, and without chordal replacement with expanded polytetrafluoroethylene sutures. J Thorac Cardiovasc Surg 1998;115:1279– 86. Schoen EJ. General pathologic considerations. In: Schoen FJ, ed. Interventional and surgical cardiovascular pathology: clinical correlations and basic principles. Philadelphia: WB Saunders Company, 1989:1–58. Fernandez J, Joyce DH, Hirschefeld K, et al. Factors affecting mitral valver reoperation in 317 survivors after mitral valve reconstruction. Ann Thorac Surg 1992;54:440– 8. Yau TM, El-Ghoneimi YAF, Armstrong S, Ivanov J, David TE. Mitral valve repair and replacement for rheumatic disease. J Thorac Cardiovasc Surg 2000;119:53– 61. Gillinov AM, Cosgrove DM, Blackstone EH, et al. Durability of mitral valve repair for degenerative disease. J Thorac Cardiovasc Surg 1998;116:734– 43. Cohn LH, Couper GS, Aranki SF, Rizzo RJ, Kinchla NM, Collins JJ Jr. Long-term results of mitral valve reconstruction for regurgitation of the myxomatous mitral valve. J Thorac Cardiovasc Surg 1994;107:143–51.