Mitral valve surgery and acute renal injury: port access versus median sternotomy

BACKGROUND: Many outcomes and complications of minimally invasive and conventional cardiac surgery await comparison. Patients undergoing mitral valve surgery commonly sustain renal injury. Using peak postoperative fractional change of serum creatinine as a marker of renal injury, we tested the hypothesis that mitral valve surgery with port access minithoracotomy (Port) and conventional surgery with a median sternotomy (MS) incision are associated with different degrees of acute renal injury. METHODS: We evaluated data from all isolated mitral valve operations by a single surgeon between 1990 and 2000 (MS = 90, Port = 227). We also performed a secondary analysis of mitral valve surgeries performed by both MS and Port approaches in a concurrent period from 1996 to 2002 (MS = 93, Port = 240). Univariable and multivariable tests were used to determine the association of surgical technique with peak postoperative creatinine (CrmaxPost) and peak postoperative fractional change in creatinine (%deltaCr); p less than 0.05 was considered significant. RESULTS: In our analysis that accounted for the date of surgery, we observed a highly significant independent association between surgical approach and %deltaCr, indicating a greater risk of acute renal injury in the MS group (F value 13.33; p = 0.0003). Similar findings were noted in the secondary (time-concurrent) analysis of %deltaCr (F value 12.65; p = 0.0176). CONCLUSIONS: We present retrospective evidence of reduced acute renal injury associated with the port access technique in mitral valve surgery patients. Our findings suggest that a port access minithoracotomy approach to mitral valve surgery may be preferable to conventional methods for patients with high renal risk.     

Mitral valve repair for bacterial endocarditis.

Twenty-two patients with mitral insufficiency resulting from native valve endocarditis underwent mitral valve repair. Six patients had acute endocarditis with positive blood cultures and active valve infection. Sixteen patients were cured of active infection, but mitral insufficiency developed as a result of prior infection. Mean age was 48.5 +/- 21.7 years; 13 (59%) were male. Mean New York Heart Association functional class was 2.6 +/- 1.2. Multiple valve lesions were present in 11 (50%) patients. Valve abnormalities included leaflet perforation in 13 patients, chordal rupture or elongation in 14, vegetations in 5; and annular abscess in 1. In patients with acute endocarditis all macroscopically infected tissue was excised. Multiple techniques were required to achieve valve competence. Suture or patch closure of perforation was done in 14 patients, chordal shortening or transfer in 9, leaflet resection and closure in 4, leaflet resection with pericardial patching in 5, and annuloplasty in 15. Mitral valvuloplasty was combined with other procedures in 11 (50%) patients. There were two (9%) hospital deaths, both occurring in patients with healed endocarditis. There was one (9%) death in a patient undergoing an isolated procedure and one (9%) in a patient undergoing a combined procedure. Mean follow-up was 24 +/- 16.8 months and was complete. Seventeen (85%) were in New York Heart Association functional class I, and three (15%) were in class II. There were no late deaths, reoperations, recurrent endocarditis, thromboembolic events, or other valve-related morbidity. We conclude that mitral valve repair for insufficiency resulting from bacterial endocarditis (1) is possible in acute and healed disease, (2) has a low operative mortality, and (3) has resulted in patients free of recurrent infection and valve-related morbidity and mortality. Mitral valve repair is an attractive alternate to valve replacement in bacterial endocarditis.     

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.     

二尖瓣成形术116例

目的　为了评价二尖瓣成形术的临床效果 ,对近年来 14岁以上行二尖瓣成形术患者的临床资料进行总结。　方法　二尖瓣病变患者 116例 ,诊断为二尖瓣狭窄 1例 ,二尖瓣狭窄合并关闭不全 6例 ,其余均为单纯二尖瓣关闭不全。超声心动图检查示左心房内径平均 4 8± 10 mm,左心室舒张期末内径平均 6 2± 10 mm。二尖瓣成形术方法 :腱索转移 2例 ,腱索折叠 10例 ,后叶楔形切除 6 7例 ,瓣环环缩 82例。　结果　全组无手术死亡 ,1例术后第 2天出现心力衰竭行二尖瓣置换术。出院前超声心动图示左心房内径平均为 37± 9m m,左心室舒张期末内径平均为 5 1±7mm ,与术前相比均明显缩小。　结论　二尖瓣成形术应根据二尖瓣病变的特征进行选择 ,对非风湿性二尖瓣病变行二尖瓣成形术可取得较满意的临床效果。     

Mitral valve repair for infective endocarditis

OBJECTIVE: This study investigated the feasibility of mitral valve (MV) repair in patients with active or healed infective endocarditis (IE) with mitral regurgitation and evaluated effects on left ventricular (LV) function and structure. METHODS: Subjects comprised 19 patients who underwent MV operations for IE between December 2004 and September 2007. MV repair was performed for acute IE in 10 of 15 patients (67%) and for healed IE in 4 of 4 patients (100%). RESULTS: No early or late postoperative deaths were encountered. One patient underwent redo MV repair owing to severe mitral regurgitation 1 month postoperatively. Postoperative echocardiography after MV repair demonstrated less than trivial (acute IE in seven, healed IE in three) or mild (acute IE in three, healed IE in one) mitral regurgitation. In patients with MV replacement, the postoperative left atrial dimension (LAD) was decreased (51.5 +/- 39.2 vs. 39.2 +/- 1.9 mm, P = 0.007); however LV end-diastolic dimension (LVDD) and LV end-systolic dimension were unchanged. In patients with MV repair, LVDD (57.5 +/- 6.5 vs. 46.0 +/- 5.6 mm, P < 0.001), LV end-systolic dimension (36.1 +/- 5.2 vs. 32.4 +/- 6.2 mm, P = 0.04), LAD (43.1 +/- 8.1 vs. 33.6 +/- 7.7 mm, P = 0.003) were reduced. Postoperative ejection fraction (55.3 +/- 13.5% vs. 41.8% +/- 10.0%, P = 0.03) and fraction shortening (30.1% +/- 9.2% vs. 20.7% +/- 5.5%, P = 0.03) were better in patients with MV repair than those with MV replacement. CONCLUSIONS: MV repair is feasible in patients with both active and healed IE. MV repair preserves better LV function and structure postoperatively.     

Mitral valve repair in patients with endomyocardial fibrosis.

Between 1987 and 1990, 12 patients were operated on for endomyocardial fibrosis at our institution. Nine were treated by endocardectomy and mitral valve repair and constitute the material of this study. Ages ranged from 9 to 58 years (mean age, 32.5 years). Biventricular involvement was present in 3 cases, and 6 patients had predominantly left ventricular endomyocardial fibrosis. Six patients were in New York Heart Association class III/IV. Six patients had severe mitral insufficiency (3 to 4/4) and 3 patients had moderate mitral insufficiency (2/4). The operation consisted of left ventricular endocardectomy with complete detachment and mobilization of the posterior leaflet of the mitral valve in all cases. An autologous pericardial patch was used to reconstruct posterior leaflet continuity in 4 patients. In 7 patients a prosthetic mitral ring was used. In 3 patients right ventricular endocardectomy and tricuspid valve repair were also performed. All patients survived and none required early reoperation. Follow-up was complete and ranged from 9 to 38 months. No late deaths occurred, and 1 patient required mitral valve replacement for recurrent mitral regurgitation. Doppler echocardiographic studies were performed in 7 patients and revealed no or mild mitral insufficiency. In conclusion, mitral valve repair is safe and offers good early and late results in patients with endomyocardial fibrosis.     

Mitral valve repair in the elderly

A case of multiple sharply circumscribed pulmonary hematomas ("coin" lesions) following blunt, non-penetrating thoracic trauma, is reported. The finding mimicked cancerous "cannon ball" metastatic deposits. A computed tomographic scan combined with puncture biopsy provided the correct diagnosis. Spontaneous complete resolution of the hematomas took 3 years.     

Mitral valve repair by Carpentier-Edwards physio annuloplasty ring.

A semi-flexible annuloplasty ring (Physio-ring) was clinically used in 30 cases of mitral valve insufficiency. The Physio-ring has the characteristics in which the anterior section is rigid and has a saddle-shaped curve, while the posterior section is flexible to allow for changes in size and shape of the anulus during ventricular contraction. The patients were aged from 23 to 73 years (mean 53.8 +/- 12.5). The cause of mitral valve insufficiency was degenerative (in 24 patients), rheumatic (2), ischemic (1), endocarditis (1), congenital + degenerative (1), and traumatic (1). On the 6-month post-implant echocardiogram, 96.6% had grade 0 or +1 regurgitation. The effective valve orifice area was 2.61 +/- 0.82 cm2 (n = 19). There was no late death. However, there was 1 (3.3%) hospital death after the patient had received a simultaneous coronary artery bypass grafting, and then developed low output syndrome after surgery. Although there was no device-related complication, hemolysis of undetermined cause was observed in 1 (3.3%) patient. The findings from this study indicated a low incidence of device-related complication, while excellent valvular function was maintained.     

Mitral valve repair in patients on chronic hemodialysis.

Two cases of successful mitral valve repair in patients on chronic hemodialysis are presented. We stress that valve repair is preferable to valve replacement whenever feasible because of improved left ventricular function, reduced complication rate, and freedom from anticoagulation. This especially applies to patients on chronic hemodialysis as they have impaired immunological function, are subjected to repeated fistula punctures with possible bacteremia, and are more susceptible to early calcification and degeneration of tissue valves.     

Partial versus full sternotomy for aortic valve replacement

Background. Recent trends suggest that smaller incisions reduce postoperative morbidity. This study tests the hypothesis that a partial upper sternotomy improves patient outcome for aortic valve replacement.

Methods. A group of 50 patients who underwent aortic valve surgery through a partial upper sternotomy (group I) were compared to 50 patients who underwent aortic valve replacement through a median sternotomy during the same time period (group II). The mean age (60 ± 2 versus 63 ± 2 years; mean ± SEM) and preoperative ejection fractions (53 ± 2 versus 54 ± 2) were similar. Operations were performed with central cannulation, and antegrade/retrograde blood cardioplegia.

Results. There was one death in each group. No differences were found in aortic occlusion time, mediastinal drainage, transfusion incidence, narcotic requirement, length of stay, or cost. The incidence of pleural and pericardial effusions was increased (18.4% versus 3.9%, p < 0.03), and the need for postoperative inotropic support was higher (38.7% versus 19.6%, p < 0.03) in the partial sternotomy group.

Conclusions. Aortic valve replacement can be performed through a partial sternotomy with results comparable to full sternotomy. The partial sternotomy offers a cosmetic benefit, but does not significantly reduce postoperative pain, length of stay, or cost.     

胸腔镜辅助与前正中开胸二尖瓣置换术的对比研究

目的 比较胸腔镜辅助与前正中开胸两种方式进行二尖瓣置换术的治疗效果,探讨胸腔镜辅助二尖瓣置换术的可行性.方法 2003年10月至2011年10月,共完成胸腔镜辅助二尖瓣置换术72例,同期完成前正中开胸二尖瓣置换74例,对两组患者的体外循环时间、升主动脉阻断时间、术后呼吸机辅助时间、胸腔引流液量、术后ICU停留时间及术后住院时间等资料进行统计学分析比较.结果 胸腔镜组体外循环时间及升主动脉阻断时间较前正中开胸时间长,且差异具有统计学意义.但两组患者的术后呼吸机辅助时间和术后ICU停留时间差异无统计学意义.胸腔镜组的胸腔引流液量少于前正中开胸组,差异具有统计学意义.结论 只要严格把握好适应证,胸腔镜辅助二尖瓣置换术可以作为常规手术开展.