Both leaflet preservation during mitral valve replacement: modified anterior leaflet preservation technique

BACKGROUND: Satisfactory results of bileaflet preserving mitral valve replacement (MVR) had forced several institutes to preserve both leaflets during MVR. Modifications were required to prevent the preserved tissue from interfering with prosthetic valve function, to implant an adequate size of valve and to prevent left ventricle outflow tract (LVOT) obstruction. MATERIALS AND METHODS: Conventional MVR was performed to 51 patients (group 1) and bileaflet preserving MVR was performed to 43 patients (group 2). Mitral anterior leaflet incised from the middle of the leaflet to mitral annulus without chordal injury in group 2 patients. Sutures were placed through the mitral annulus first and then passed from the bottom to the tip of anterior leaflet. Posterior leaflet was also preserved. Prosthetic valve was put down into the mitral annulus and sutures were ligated. Excessive anterior leaflet tissue was attached to left atrial wall. RESULTS: Cross-clamping time was 45 +/- 5.33 minutes versus 61.32 +/- 4.43 minutes (p = 0.0001) and total cardiopulmonary bypass time was 60.80 +/- 4.44 minutes versus 80.55 +/- 3.65 minutes (p = 0.0001) in groups 1 and 2, respectively. Inotropy requirement was higher in group 1 (p = 0.0058). When compared with preoperative values postoperative left ventricle ejection fraction (LVEF) increased both at rest (from 52.74% +/- 3.88% to 62.86% +/- 3.18%, p = 0.0001) and during exercise (from 53.16% +/- 3.16% to 64.11% +/- 2.46%, p = 0.0001) in bileaflet preserving MVR group. But in conventional MVR group LVEF decreased postoperatively both at rest (from 51.45% +/- 4.27% to 48.27% +/- 3.35%, p = 0.0001) and during exercise (from 54.47% +/- 7.36% to 42.96% +/- 3.58%, p = 0.0001). CONCLUSION: Leaflet preserving MVR operation not only improves the left ventricular performance but also reduces the mortality and morbidity after MVR. LVEF increases both at rest and during exercise. Risk of LVOT obstruction can be completely eliminated with our simple technique.     

Artificial chordae

Expanded polytetrafluoroethylene sutures have been used for replacement of chordae tendineae since 1985. They have been used for correction of prolapse of mitral and tricuspid valve leaflets as well as for resuspension of the papillary muscles during mitral valve replacement when the native chordae cannot be preserved to maintain continuity between the mitral annulus and papillary muscles. The sutures used were 5CV Gore-Tex for replacement of the chordae tendineae of the anterior leaflet and 6CV for the posterior leaflet and commissural areas of the mitral valve. Initially one suture was used to create two artificial chordae, but as experience increased, the technique was modified and multiple pairs of artificial chordae were created with a single suture by passing successively through the fibrous portions of the a papillary muscle and the free margin of the prolapsing segment of leaflet, and tying the tends together on the papillary muscle head. This technique creates artificial chordae that are interdependent and their lengths are self-adjusting when pressure is exerted on the leaflets. From 1985 to 1998, 288 patients had artificial chordae used during mitral valve repair for degenerative disease of the mitral valve. Prolapse of both leaflets was present in 51% of patients, isolated prolapse of the anterior leaflet in 28%, and posterior leaflet in 21%. The mean follow-up was 4.8 +/- 3.0 years and was complete. At 10 years, the freedom from mitral regurgitation >2+ was 88 +/- 6% and the freedom from reoperation was 92 +/- 2%. Failures of repair were unrelated to the artificial chordae. Gore-Tex sutures are an excellent material to replace chordae tendineae, appear to be free of adverse effects, and have become a valuable adjunct to the surgical armamentarium to treat mitral and tricuspid valve disease.     

Early and mid-term results of mitral valve repair using premeasured Gore-Tex loops ('loop technique')

OBJECTIVE: Mitral valve (MV) repair with premeasured Gore-Tex loops (the 'loop technique') was introduced in 1999. We assessed the early- and mid-term outcomes for the loop technique in patients with MV prolapse. METHODS: A total of 632 patients (447 male, 185 female) underwent MV repair with Gore-Tex loops for MV prolapse. A mini-thoracotomy was performed in 522 patients (mean age 58+/-12.4 years) and 110 patients received a full sternotomy (mean age 66.5+/-11.9 years). Early postoperative echo was performed in all patients and clinical follow-up was obtained in 95% of patients. RESULTS: Loops were used to correct prolapse of the posterior leaflet in 308 patients, the anterior leaflet in 150 patients, and both leaflets in 174 patients. The mean length of Gore-Tex loops was 20.8+/-3.4 mm for the A2 segment and 14.3+/-3.0mm for the P2 segment. Concomitant procedures consisted of atrial fibrillation ablation in 123 patients, tricuspid valve repair in 30 patients, coronary bypass surgery in 73 patients, and aortic valve surgery in 21 patients. Mean aortic cross-clamp and cardiopulmonary bypass times were 89+/-32 and 137+/-43 min, respectively. Predischarge echocardiography revealed no residual mitral regurgitation (MR) in 75%, trace or mild MR in 21% and mild-to-moderate MR in 4% of patients. Thirty-day survival was 98.6%, and one-year survival was 97.1%. Freedom from reoperation was 97.4+/-1.4%, 3 years postoperatively. CONCLUSION: MV repair with premeasured Gore-Tex loops results in excellent early- and mid-term outcomes for all types of leaflet prolapse. The loop technique facilitates minimal invasive MV repair without compromising surgical outcomes.     

Mitral valve repair with artificial chordal creation

To achieve optimal long-term result of mitral valve repair, artificial chordae creation has got to be an important technique. Artificial chordae creation can preserve leaflet motion of the posterior mitral leaflet and soft coaptation area. Loop technique is suitable technique for creation of multiple artificial chordae, especially in minimally invasive minithoracotomy setting. Loop-in-loop technique is a new technique to realize easy adjusting of the length of the neochordae using slippery Gore-Tex suture. Loop-in-loop technique helps surgeons to afford variety of mitral valve repair techniques and manage complex mitral valve pathologies.     

Early clinical experience with the On-X prosthetic heart valve

The study aimed to assess the performance of the On-X valve (Medical Carbon Research Institute, Austin, TX). Between December 2000 and January 2003 On-X valves were implanted in 400 patients aged 19-85 years (mean: 55.6+/-16), 290 males and 210 females. There were 120 cases of aortic valve replacement (AVR), 258 mitral valve replacement (MVR) and 22 combined aortic and mitral valve replacement (DVR). Additional procedures were performed in 144 patients. Patients were followed up prospectively at 3- to 6-month intervals. Mean follow-up was 38.4+/-11.8 months (maximum 55.6 months). Overall hospital mortality was 3.5%. Freedom from adverse events at 4 years in the study were as follows: thromboembolism, 99.1% for AVR, 98.3% for MVR and 94.7% for DVR patients; thrombosis, 100% for AVR, 99.2% for MVR and 94.7% for DVR; bleeding events, 99.1% for AVR, 99.2% for MVR and 88.8% for DVR; prosthetic endocarditis, 98.2% for AVR, 99.2% for MVR and 94.7% for DVR. Overall survival at 4 years was 92+/-1%. At echocardiographical examination within 1 year of the AVR, the mean aortic valve gradient was 12.8+/-6, 10.3+/-3, 9.0+/-4, 8.3+/-3, and 6.2+/-3 mmHg for 19, 21, 23, 25, 27/29 mm valve sizes, respectively. MVR mean gradient was 4.9+/-2, 4.5+/-1.2 and 4.0+/-0.8 mmHg for 25, 27/29, 31/33 mm valve sizes, respectively. On-X valve is a highly effective mechanical valve substitute with low morbidity and mortality and good functional results.     

Mitral valve repair for ischemic mitral insufficiency.

Over a 5-year period, 1,292 patients had operation on their native mitral valves. Ischemia was the cause of mitral insufficiency in 84 patients (6.5%). Sixty-five patients (77.4%) had mitral valve repair. Mean age was 66 +/- 10 years; 35 patients (53.8%) were women. Mean degree of preoperative insufficiency was 3.2 +/- 0.7; mean preoperative New York Heart Association functional class was 3.3 +/- 0.7. Eleven patients (16.9%) had acute and 54 (83.1%) had chronic mitral insufficiency. Valve prolapse was present in 26 patients (40%). Restrictive leaflet motion secondary to regional or global left ventricular dilatation occurred in 39 patients (60%). All patients had associated myocardial revascularization followed by transatrial valvuloplasty. Multiple techniques were employed to achieve valve competence: leaflet resection (3), chordal shortening (15), papillary muscle reimplantation (10), papillary muscle shortening (3), and annuloplasty (63). There were six (9.2%) hospital deaths (acute, 9.1%; chronic, 9.3% [not significant]; prolapse, 11.5%; restrictive, 7.7% [not significant]). The mean degree of postoperative mitral insufficiency was 0.6 +/- 0.8 in 51 patients. At a mean follow-up of 3.1 +/- 1.6 years, patient survival was 96% for patients with valve prolapse and 48% for those with restrictive leaflet motion (p = 0.02). New York Heart Association functional class was improved in all groups. Ischemic mitral insufficiency is an uncommon cause of mitral valve disease that is amenable to repair in the majority of cases of both acute and chronic onset. The operative mortality is low, and operation is associated with superior survival in patients with valve prolapse.     

Artificial chordae for pediatric mitral and tricuspid valve repair.

OBJECTIVE: To evaluate pediatric atrioventricular valve repair with artificial chordae. METHODS: Between February 2001 and January 2006, artificial chords were used in 21 children with severe mitral or tricuspid valve regurgitation. Patients with AVSD were excluded. Median age was 84 (1-194) months. Five patients had isolated tricuspid valve anomalies, 16 had mitral valve anomalies (associated tricuspid annular dilatation in 4). Tricuspid neochordae were placed to anterior (three patients) and septal (two patients) leaflets. Mitral neochordae were placed to anterior (15 patients) and posterior (1 patient) leaflets. Additional ring annuloplasties were performed in 12 (mitral 11, tricuspid 1), as well as 2 de Vega tricuspid annuloplasties. Patch insertion was used in acute endocarditis (tricuspid one). All echocardiographic studies were reviewed and analyzed by a single cardiologist. RESULTS: No mortality occurred. Follow-up was complete (mean 28+/-18 months). Two patients were reoperated, one for mitral ring dehiscence and one for recurring mitral valve insufficiency. Both valves were replaced by mechanical valve prosthesis. At last follow-up tricuspid insufficiency was mild (three) or moderate (two). Moderate insufficiency occurred due to remaining restriction of the septal leaflet after repair in endocarditis (one) and remaining prolapse of the anterior leaflet (one). Mitral insufficiency was absent (five), mild (seven), or moderate (two). Moderate insufficiency was caused by recurrent anterior leaflet shortening after valve repair in rheumatic valve disease (two). Valve restriction caused by artificial chordae was not found. CONCLUSIONS: Mitral and tricuspid valve repair with artificial chordae in children demonstrated acceptable results. Despite patient growth, valvular restriction by the artificial chordae was not observed ad mid-term follow-up.     

The Mitroflow pericardial bioprosthesis. Comparison of early clinical performance in aortic and mitral positions.

Between 1983 and 1987 the Mitroflow pericardial prosthesis was implanted in 354 patients, ranging in age from 14 to 94 years (mean 60.1 years). The early mortality was 5.7% and the late mortality 2.9% per patient-year. The total cumulative follow-up was 853 years (mean 2.4 years). Patient survival at 4 years for aortic valve replacement (AVR) was 81.5% and for mitral valve replacement (MVR) 74.8%. The overall rate of valve-related complications was 4.8% per patient-year (41 complications): thromboembolism, 15; hemorrhage related to antithromboembolic therapy, 1; prosthetic valve endocarditis, 15; nonstructural dysfunction, 3; and structural valve deterioration, 7. At 4 years the freedom from thromboembolism was 91.5% +/- 2.7% for AVR and 91.1% +/- 4.0% for MVR, from prosthetic valve endocarditis 93.5% +/- 2.3% for AVR and 94.0% +/- 2.9% for MVR, from structural valve deterioration 97.3% +/- 2.1% for AVR and 92.6% +/- 3.2% for MVR, from valve-related mortality 96.9% +/- 1.4% for AVR and 97.5% +/- 1.8% for MVR, and from reoperation 93.5% +/- 2.8% for AVR and 83.1% +/- 5.1% for MVR. The freedom from the composite of all valve-related complications at 4 years was 81.1% +/- 4.2% for AVR and 75.3% +/- 2.8% for MVR. The Mitroflow valve has provided satisfactory clinical performance at the 4-year evaluation. Structural valve deterioration is greater in the mitral position than in the aortic position. Long-term evaluation of the Mitroflow valve is necessary to determine the impact of structural valve deterioration on its clinical performance.     

Four year follow-up of the Duromedics Edwards bileaflet valve prostheses

The Duromedics Edwards (DE) bileaflet valve prosthesis was withdrawn from the market after 12 leaflet escapes had been reported in 20,000 implants. Effort is necessary to identify the failure mode to improve valve design or production, but the rate of other valve related complications will tell if it is worthwhile reintroducing this prosthesis. Five-hundred and sixty-four DE valves have been implanted in 508 patients between September 1983 and May 1988. Two-hundred and sixty-eight had aortic valve replacement (AVR), 183 mitral valve replacement (MVR) and 56 double valve replacement (DVR); the perioperative mortality was 6.9%. Follow-up has been 98.7% complete for a total of 1064 patient years and a mean follow-up of 26 months (range 3 to 54 months). Late mortality was 3.7%/yr and actuarial survival was 85 +/- 3% without and 78 +/- 3% including operative mortality after 54 months. Event free actuarial rates (linearized rates in parenthesis) were 93 +/- 2% (1.5%/yr) for thromboembolism, 91.7 +/- 1.9% (2.3%/yr) for anticoagulant related hemorrhage, 89 +/- 4.8% (2.3%/yr) for valve failure, 93 +/- 2% (1.8%/yr) for valve related mortality, 72 +/- 4.8% (6.3%/yr) for all valve related morbidity and mortality and 83 +/- 4.4% (3%/yr) for treatment failure. Two leaflet escapes occurred in the study group (0.18%/yr), both patients survived reoperation. The concept of reducing thrombus formation by a specially designed irrigating hinge mechanism was proven by a low rate of thromboembolism in our clinical follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)     

Midterm experience with the Sorin Bicarbon heart valve prosthesis for rheumatic disease

BACKGROUND: In this study, we present a single center experience with Bicarbon bileaflet valve in 307 patients with rheumatic heart disease. METHODS: Between August 1998 and September 2000, 307 patients underwent heart valve replacement using the Bicarbon bileaflet valve (Sorin Biomedica, Saluggia, Italy) with an average age of 47.19+/-13.21 years (range 14 to 80 years), consisting of 147 males and 160 females at Alkan Hospital, Cardiovascular Surgery Department. Aortic valve replacement (AVR) was performed in 77 patients, mitral valve replacement (MVR) in 156 patients and double valve replacement (DVR) in 74 patients. RESULTS: The early mortality rate was 3.3% (10/307) and there was no late mortality. The actuarial survival rate, including hospital mortality, was 96.74+/-1.01% for the whole group, 96.5+/-1.5% for the MVR group, 97.4+/-1.8% for the AVR group and 97.3+/-1.9% for the DVR group at 35 months. One patient had obstructive valve thrombosis with MVR. The 35 months actuarial freedom from valve thrombosis was 99.58+/-0.4% for the whole group. Four patients were reoperated and the 35 months actuarial freedom from reoperation was 98.53+/-0.7% for the whole group, 98.65+/-0.9% for the MVR group, 96.73+/-02% for the DVR group and 100% for the AVR group. No instances of perivalvular leak, hemolysis, endocarditis or embolism were observed during the entire follow-up period. Mean follow-up duration was 16.5+/-7.9 months (ranged 4 to 35 months). CONCLUSION: We have presented our mid-term results with the Sorin Bicarbon bileaflet valve in patients with rheumatic heart disease, which provided good clinical performance combined with meticulous patient care and advanced surgical techniques.     

Mitral valve prolapse. Comparison between valvular repair and replacement in severe mitral regurgitation

BACKGROUND: The aim of this study was to analyse long term results of mitral valve repair of degenerative mitral regurgitation compared to valve replacement. METHODS: A hundred-twenty-five consecutive patients with severe mitral valve insufficiency who underwent cardiac surgery from January 1987 to December 1995 were included in the study. Mean age was 55+/-16 years (77 males, 48 females). Mitral repair was performed in 62 patients and mitral valve was replaced in 63 patients. Mean follow-up was 5 years. The repair procedures were based on quadrangular resection of the posterior leaflet, chordal replacement and transposition. Annuloplasty was performed in 100% of cases. The technique of valve replacement was conventional with complete excision of the valve in the majority of cases. RESULTS: Operative mortality following valve repair was 1.6%, no death occurred in the prosthesic group. In the repair group overall survival and re-operation rate were respectively 95.2% and 6.5%, while in the replacement group were 93.7% and 7.9%. No endocarditis and thromboembolic accidents were observed following valvuloplasty, while in the prostheses 6.3% of patients had endocarditis and 1.6% had a thromboembolic event. Mild or moderate left ventricular dysfunction was present in 5 patients after valvuloplasty and in 9 patients with prostheses. CONCLUSIONS: Considering these results we conclude that, in patients with severe degenerative mitral insufficiency, mitral valve repair is warranted whenever it is possible. The advantages given by maintaining the native valve suggest that surgery should be considered in asymptomatic patients before the occurrence of the left ventricular dysfunction.     

Midterm result of leaflet extension technique in aortic regurgitation.

OBJECTIVES: Aortic valve leaflet extension using glutaraldehyde-fixed autopericardium in aortic regurgitation (AR) is technically demanding, and it is not a popular procedure among surgeons. This study evaluates the effectiveness and clinical feasibility of the leaflet extension technique as a treatment modality for AR. MATERIALS AND METHODS: From March 1995 to March 2001, 34 consecutive patients underwent the leaflet extension technique. The mean age of the 26 men and eight women was 31.0+/-14.3 years (range 16-68). They were all diagnosed with pure aortic valve regurgitation, and nine (27.3%) had associated mitral valvular heart diseases. Accurate measurement of the leaflet free margins was performed with a pair of compasses before leaflet extension. Glutaraldehyde-fixed autopericardium was designed according to the free margin lengths. Leaflet extension was performed in three aortic leaflets for 29 patients but only one leaflet was extended in the remaining four. The nine patients with associated mitral valvular heart disease also underwent mitral valvuloplasty. Mean cardiopulmonary bypass time and ischemic time in 25 isolated AR group were 128.7+/-26.5min (range 70--180) and 101.5+/-25.5min (range 41-150), respectively. RESULTS: There was no incidence of in-hospital mortality. Immediate postoperative echocardiography revealed grade II AR in one, grade I AR in ten and no AR in the remaining 23 patients. Mean follow-up duration was 49.6+/-18.8 months (range 4.1-77.1). Echocardiographic AR grades during follow-up were grade II in 13, grade I in 11 and no AR in eight. The remaining two patients underwent reoperation, one aortic valve replacement because of subacute bacterial endocarditis that occurred 7 months after leaflet extension, and the other Ross operation because of the dehiscence of the valvuloplasty suture site that developed 4 months later (AR associated with Behcet's disease). There was one case of mortality due to malignant mesothelioma 4 years after aortic valvuloplasty. The cumulative survival rate was 94.1% at 5 years. Freedom from reoperation was 93.8% at 1 year and after. CONCLUSIONS: The leaflet extension technique is an acceptable surgical treatment modality for AR and its clinical results were confirmed in this study to be very good. A careful long-term follow-up study will be necessary to evaluate the long-term durability of the glutaraldehyde-preserved autologous pericardium as a leaflet tissue.     

保留后瓣及瓣下结构的二尖瓣置换术临床分析

目的总结保留二尖瓣后瓣及瓣下结构二尖瓣置换术(MVR)的经验,评价其临床效果。方法回顾性分析首都医科大学北京安贞医院2006年1月至2011年3月行MVR患者1 035例的临床资料,其中男562例,女473例;年龄37～78(53.84±13.13)岁。风湿性心脏瓣膜病712例,退行性瓣膜病323例;二尖瓣狭窄为主389例,二尖瓣关闭不全为主646例;均排除冠状动脉疾病。不保留后瓣及瓣下结构的MVR(不保留组)457例,保留后瓣及瓣下结构的MVR(保留组)578例,两组患者术前情况差异无统计学意义。分析比较两组患者手术后并发症、死亡率,以及左心室大小与功能。结果不保留组与保留组患者的死亡率(2.63%vs.1.21%,P=0.091)及并发症发生率(8.53%vs.7.44%,P=0.519)差异无统计学意义,但不保留组左心室破裂发生率高于保留组(1.09%vs.0.00%,P=0.012);术后6个月心脏超声心动图提示左心室舒张期末内径(LVEDD)较术前缩小,但两组差异无统计学意义;两组患者左心室射血分数(LVEF)均较术前提高,保留组中二尖瓣关闭不全为主患者的LVEF优于不保留组(56.00%±3.47%vs.53.00%±3.13%,P=0.000),两组二尖瓣狭窄为主的患者中LVEF差异无统计学意义(57.00%±5.58%vs.56.00%±4.79%,P=0.066)。结论保留二尖瓣后瓣及瓣下结构的MVR安全有效,可以减少术后左心室破裂的发生并改善术后心功能。     

Eight year experience with the CarboMedics bileaflet valvular prosthesis.

Two hundred and two patients (97 female and 105 male; mean age: 45. 5+/-9 years) received CarboMedics bileaflet valves during a period of eight years. Ninety-one patients received mitral, 72 aortic and 39 aortic+mitral valve prosthesis. Tricuspid plasty and coronary artery bypass surgery were the concomitant operations in 17 and 12 patients, respectively. The mean follow-up period was 24.7 months and the ratio was 91%. Overall operative mortality was 3.96% (8 patients); 2.78% for aortic valve replacement (AVR), 3.29% for mitral valve replacement (MVR) and 7.7% for double valve replacement (DVR). The late mortality rate was 2.89% for AVR, 2.2% for MVR and 8. 3% for DVR. The main cause of mortality was low cardiac output. The overall survival rate was 91.5% in 2 years. The actuarial freedom from thromboembolism in 2 years was 97% for AVR, 95% for MVR and 84% for DVR. No mortality due to heamorrhagic events was observed. CarboMedics prosthetic heart valves may be used satisfactorily with a low incidence of valve-related morbidity and mortality.     

Mitral valve repair for degenerative disease: is pericardial posterior annuloplasty a durable option?

OBJECTIVE: Biological and prosthetic rings are available for supporting mitral valve repair (MVR). Contrasting data are reported on the durability of pericardial ring annuloplasty. This retrospective study was undertaken to assess the durability of MVR for degenerative regurgitation with posterior annuloplasty performed with glutaraldehyde-treated autologous pericardium. METHODS: From August 1995 through December 2000, 133 patients underwent mitral repair for degenerative regurgitation (86 men, age 62.9+/-11.5 years). Thirty patients (22.6%) underwent combined coronary artery bypass graft and fourteen (10.5%) underwent tricuspid annuloplasty. Associated aortic disease, previous cardiac surgery and endocarditis were considered exclusion criteria. RESULTS: Seventy-seven patients (57.9%) received a Carpentier-Edwards ring and 56 received (42.1%) an autologous pericardium ring. Thirty-day mortality was 3.8%. Mean follow-up, 98.3% complete, was of 35.6+/-18.7 months. Five-year freedom from reoperation and recurrence of mitral regurgitation> or =3+/4+ was significantly higher in the prosthetic ring group (90.1% - CL90%: 81.9-98.3%) compared with the pericardial ring group (62.6% - CL90%: 43.1-82.1%; P=0.027). Prosthetic ring implantation (P=0.004; RR=0.11) and preoperative New York Heart Association (NYHA) class< or =II (P=0.011; RR=0.16) were independently related to a lower risk of reoperation and recurrence of mitral regurgitation> or =3+/4+, by multivariate analysis. Five-year overall survival was 91.4% (CL90%: 87.9.7-95%). A higher preoperative left ventricular end-diastolic diameter (P=0.006; RR=1.17) and the severity of associated coronary artery disease (P=0.021; RR=2.00) were independent predictive factors for poor survival by multivariate analysis. CONCLUSIONS: Posterior pericardial annuloplasty can jeopardize reproducibility and durability of MVR for degenerative regurgitation.     

The Medtronic-Hall cardiac valve: 7 1/2 years' clinical experience

Clinical information on the Medtronic-Hall valve prosthesis was obtained by reviewing the records of 379 patients, 164 of whom had aortic valve replacement (AVR), 163 of whom had mitral valve replacement (MVR), and 52 of whom had double valve replacement over 90 months (1,225 patient-years) (mean follow-up, 42.01 +/- 1.3 months [+/- standard error]). Mean age was 53.8 +/- 12 years. One hundred ninety-three patients (50.9%) had some type of concomitant operation, such as tricuspid annuloplasty, coronary artery bypass grafting, or resection of ascending aortic aneurysm. Ninety-one percent were in New York Heart Association (NYHA) Functional Class III or IV preoperatively. Early mortality and late mortality were 7.7% (29 patients) and 13.5% (51 patients), respectively. The actuarial survival at 7 1/2 years was 74.1 +/- 2.7% for the total group and 69.0 +/- 4.5% for those having AVR, 81.0 +/- 3.2% for those having MVR, and 67.0 +/- 8.9% for those having double valve replacement. All patients but 2 were maintained on a regimen of chronic anticoagulation with warfarin sodium. Twenty-six thromboembolic episodes occurred (2.1/100 patient-years): 13 after MVR (2.3/100 patient-years), 11 after AVR (2.1/100 patient-years), and 2 after double valve replacement (1.4/100 patient-years). Four thromboembolic episodes were fatal; no valve thrombosis occurred. There were no structural failures. Of the 350 late survivors, 92% were in NYHA Functional Classes I and II. Total valve-related complications have been minimal.(ABSTRACT TRUNCATED AT 250 WORDS)     

Redo valve surgery with on-pump beating heart technique

AIM: Reoperations have become of increasing frequency in the last four decades. Redo surgery is more complex than primary surgery and is associated with higher mortality and morbidity. We present our immediate and mid-term results of mitral and aortic prosthetic valve replacement undertaken with beating heart technique. METHODS: The prospective study included 26 consecutive redo valve surgery patients who underwent valve re-replacement. The operation was carried out on a beating heart using normothermic bypass without cross-clamping the aorta for mitral valve surgery and retrograde coronary sinus normothermic noncardioplegic blood perfusion during cross-clamping the aorta for aortic valve procedures. RESULTS: Twenty-six patients (mean age 50+/-15 years) underwent reoperation with beating heart technique. Twenty (76.9%) mitral prosthetic replacements, 4 (15.4%) aortic prosthetic replacements, and 2 (7.7%) double valve replacements were achieved. Fourteen patients (53.8%) were operated for prosthetic valve dysfunction. Eighteen patients (69.2%) were in NYHA class III or IV preoperatively. Mean bypass time was 85+/-30 min. Mean duration of ventilation was 13.6+/-6 h, mean intensive unit stay was 2.8+/-6.4 days, and mean hospital stay was 8.3+/-7.2 days. Two (7.7%) patients required high dose inotropic support and in one patient (3.8%) intra-aortic balloon support was required. Pulmonary complication occurred in 1 patient (3.8%), low cardiac output in 1 patient (3.8%), and re-exploration for bleeding in 2 patients (7.7%). Operative mortality was not observed. CONCLUSION: Normothermic on-pump beating heart valve replacement offers a safe alternative to cardioplegic arrest in high-risk group. Complication rates are low and perioperative mortality is lower than with conventional surgery. Beating heart technique has the advantage of maintaining physiologic condition of the heart throughout the procedure.     

The double-orifice technique in mitral valve repair: a simple solution for complex problems

OBJECTIVE: The aim of this study is to report our results with the central double-orifice technique used for the treatment of complex mitral valve lesions. METHODS: The central double-orifice repair has been used in 260 patients (mean age, 56 +/- 14.3 years) over a period of 7 years. The mechanism responsible for mitral regurgitation was prolapse of both leaflets in 148 patients, prolapse of the anterior leaflet in 68, prolapse of the posterior leaflet with annular calcification or other unfavorable features in 31, and lack of leaflet coaptation for restricted motion or erosion of the free edge in 13. Degenerative disease was the cause of mitral regurgitation in 80.8% of the patients, rheumatic disease was the cause in 9.6%, endocarditis was the cause in 6.1%, and ischemic disease was the cause in 2.3%. RESULTS: Hospital mortality was 0.7%, and the overall survival at 5 years was 94.4% +/- 2.59%. Thirteen patients required a reoperation (2 early postoperatively and 11 late during the follow-up), for an overall freedom from reoperation of 90.0% +/- 3.37% at 5 years. Freedom from reoperation was lower in patients with rheumatic valve disease and in patients who did not undergo an annuloplasty procedure. CONCLUSIONS: The effectiveness and durability of the central double-orifice technique were assessed in this study. This type of repair can be a useful addition to the surgical armamentarium in mitral valve reconstruction.     

Clinical performance of the Duromedics bileaflet pyrolite mechanical prosthesis.

The Duromedics (Baxter Healthcare Corp., Edwards CVS Div., Irvine, Calif.) mechanical cardiac valvular prosthesis was implanted in 480 patients between 1984 and 1987 at the Montreal Heart Institute, the Hospital Clinic of Barcelona and the teaching hospitals of the University of British Columbia. The mean age of the patients was 52 years. The early mortality was 7.9% and the late mortality was 4.1% per patient-year. The overall survival at 4 years for aortic valve replacement (AVR) was 87.0% +/- 3.7% and for mitral valve replacement (MVR) was 81.9% +/- 2.9%. There were 16 valve-related reoperations in 14 patients--for prosthetic valve endocarditis in 9 patients, for thromboembolism in 1 patient and for nonstructural dysfunction in 4 patients. The freedom from thromboembolism at 3 and 4 years was 94.3% +/- 3.1% for AVR and 95.1% +/- 1.8% for MVR. The freedom from prosthetic valve endocarditis at 3 and 4 years was 95.3% +/- 2.2% for AVR and 96.2% +/- 1.6% for MVR. The freedom from structural valve deterioration for all positions was 100%. The freedom from reoperation at 4 years was 95.3% +/- 2.1% for AVR and 92.3% +/- 4.3% for MVR and from valve-related death was 98.7% +/- 1.3% for AVR and 96.2% +/- 1.6% for MVR. The freedom from all valve-related complications at 4 years was 87.7% +/- 3.8% for AVR and 85.7% +/- 2.9% for MVR. Long-term evaluation of the Duromedics prosthesis is required to determine the influence of documented structural valve deterioration.     

Surgery for cardiac valves and aortic root without cardioplegic arrest ("beating heart"): experience with a new method of myocardial perfusion

Simultaneous antegrade/retrograde warm blood perfusion with a beating heart has not been previously reported as a mean of protecting hypertrophied hearts in cardiac valve and aortic root surgeries. Similarly, beating heart mitral valve surgery via the trans-septal approach with the aorta unclamped, is a novel technique. We, herein, report a series of 346 patients with a variety of cardiac pathologies who were operated upon utilizing a new modality of myocardial perfusion. Among this group of patients, there were 55 patients who were diagnosed with endocarditis of one or more valves. These patients were excluded from this series of patients. Mean age was 59 +/- 12, and there were 196 (67.3%) males and 95 (32.7%) females. There were six aortic root procedures, 90 mitral valve replacements (MVR), 46 mitral valve repairs, 20 MVR+ coronary artery bypass grafting (CABG), 28 tricuspid valve repairs, 106 aortic valve replacements (AVR), 17 AVR+CABG, and 8 AVR/MVR. Crude mortality for the group was 20 of 291 (6.8%). Intra-aortic balloon pump utilization at time of weaning from cardiopulmonary bypass was 6/291 (2.06%), and re-operation for bleeding was needed in 12 of 291 (4.1%) patients. Postoperative stroke occurred in 4 of 291 (1.3%) patients. In these patients, the clinical diagnosis of stroke was made prior to surgery. This initial experience with this new method of myocardial perfusion indicates that results are at least comparable, if not superior, to conventional techniques utilizing intermittent cold blood cardioplegia.