Faculty Bibliography

OBJECTIVE: To analyze the effectiveness of new techniques of mitral valve reconstruction (MVR) that have evolved over the last decade, such as aggressive anterior leaflet repair and minimally invasive surgery using an endoaortic balloon occluder. SUMMARY BACKGROUND DATA: MVR via conventional sternotomy has been an established treatment for mitral insufficiency for over 20 years, primarily for the treatment of patients with posterior leaflet prolapse. METHODS: Between June 1980 and June 2001, 1,195 consecutive patients had MVR with ring annuloplasty. Conventional sternotomy was used in 843 patients, minimally invasive surgery in 352 (since June 1996). Anterior leaflet repair was performed in 374 patients, with increasing use over the last 10 years. Follow-up was 100% complete (mean 4.6 years, range 0.5-20.5). RESULTS: Hospital mortality was 4.7% overall and 1.4% for isolated MVR (1.1% for minimally invasive surgery vs. 1.6% for conventional sternotomy; =.4). Multivariate analysis showed the factors predictive of increased operative risk to be age, NYHA functional class, concomitant procedures, and previous cardiac surgery. The 5-year results for freedom from cardiac death, reoperation, and valve-related complications among the 782 patients with degenerative etiology are, respectively, as follows ( >.05 for all end points): for anterior leaflet repair, 93%, 94%, 90%; for no anterior leaflet repair, 91%, 92%, 91%; for minimally invasive surgery, 97%, 89%, 93%; and for conventional sternotomy, 93%, 94%, 90%. CONCLUSIONS: These findings indicate that late results of MVR after minimally invasive surgery and after anterior leaflet repair are equivalent to those achievable with conventional sternotomy and posterior leaflet repair. These options significantly expand the range of patients suitable for mitral valve repair surgery and give further evidence to support wider use of minimally invasive techniques

BACKGROUND: This study analyzes a single institutional experience with minimally invasive mitral valve operations of 6 years, reviewing short-term morbidity and mortality and long-term echocardiographic follow-up data. METHODS: Seven hundred fourteen consecutive patients had minimally invasive mitral valve procedures between November 1995 and November 2001; concomitant procedures included 91 multiple valves and 18 coronary artery bypass grafts. Of these 714 patients, 561 patients had isolated mitral valve operations (375 repairs, 186 replacements). Mean age was 58.3 years (range, 14 to 96 years; 30.1% > 70 years), and 15.4% of patients had previous cardiac operations. Arterial cannulation was femoral in 79.0% and central in 21%, with the port access balloon endo-occlusion used in 82.3%. Cardioplegia was transjugular retrograde (54.1%) or antegrade (29.4%). Right anterior minithoracotomy was used in 96.6% and left posterior minithoracotomy in 2.2%. RESULTS: Hospital mortality for primary isolated mitral valve repair was 1.1% and 5.8% for isolated mitral valve replacement. Overall hospital mortality was 4.2% (30 of 714). Mean cross-clamp time was 92 minutes and mean cardiopulmonary bypass time was 127 minutes. Postoperatively, median ventilation time was 11 hours, intensive care unit time was 19 hours, and total hospital stay was 6 days. Complications for all patients included permanent neurologic deficit (2.9%), aortic dissection (0.3%); there was no mediastinal infection (0.0%). Follow-up echocardiography demonstrated 89.1% of the repair patients had only trace or no residual mitral insufficiency. CONCLUSIONS: This study demonstrates that the minimally invasive port access approach to mitral valve operations is reproducible with low perioperative morbidity and mortality and with late outcomes that are equivalent to conventional operations

The formation of blood capillaries from preexisting vessels (angiogenesis) and vascular remodeling secondary to atherosclerosis or vessel injury are characterized by endothelial cell migration and proliferation. Numerous growth factors control these cell functions. Basic fibroblast growth factor (FGF-2), a potent angiogenesis inducer, stimulates endothelial cell proliferation, migration, and proteinase production in vitro and in vivo. However, mice genetically deficient in FGF-2 have no apparent vascular defects. We have observed that endothelial cell migration in response to mechanical damage in vitro is accompanied by activation of the extracellular signal-regulated kinase (ERK) pathway, which can be blocked by neutralizing anti-FGF-2 antibodies. Endothelial cells from mice that are genetically deficient in FGF-2 neither migrate nor activate ERK in response to mechanical wounding. Addition of exogenous FGF-2 restores a normal cell response, which shows that impaired migration results from the genetic deficiency of this growth factor. Injury-induced ERK activation in endothelial cells occurs only at the edge of the wound. In addition, FGF-2-induced ERK activation mediates endothelial cell migration in response to wounding without a significant effect on proliferation. These data show that FGF-2 is a key regulator of endothelial cell migration during wound repair

BACKGROUND: Repair of functional ischemic mitral regurgitation (MR) due to annular deformity and leaflet restriction remains a challenge for the surgeon and lacks well-documented outcomes. We investigated outcomes in the treatment of functional ischemic MR corrected by annuloplasty techniques alone. METHODS: From May 1980 to July 1999, 174 patients underwent repair for functional ischemic mitral insufficiency with annuloplasty alone (128 ring annuloplasty; 46 suture annuloplasty). Acute insufficiency was present in 25 (14.4%). Concomitant procedures included CABG (n = 152; 87.4%). Patients were studied longitudinally with annual follow-up and echocardiograms. RESULTS: Overall hospital mortality was 17.8% and was increased by NYHA Class 4 (23.8% vs. 8.7%; p = 0.011), diabetes (25.0% vs. 13.6%; p = 0.059), and chronic mitral insufficiency (16.4% vs. 8.0%; p = 0.070). Multivariate analysis revealed age (beta = 0.099; p = 0.049) and ejection fraction < 30% (beta = 1.260; p = 0.097) as significant predictors of hospital death. Mean postoperative mitral insufficiency was 0.84 +/- 0.86 (scale of 0-4). NYHA Class 4 (beta = 2.33; p = 0.034) and simple suture annuloplasty (beta = 2.08; p = 0.07) were associated with increased risk of late cardiac death. Cumulative incidence of mitral reoperation was 7.7% at 5 years. At follow-up, 89.7% of patients were in NYHA Class 1 or 2 with 83.4% having none or only mild mitral insufficiency. CONCLUSIONS: Ring annuloplasty is associated with a survival benefit when compared to simple suture repair in ischemic patients who require annuloplasty alone to correct the MR. Mitral reconstruction with a ring annuloplasty offers durable results in this homogeneous subset of functional ischemic MR patients. Ischemic mitral insufficiency is associated with significant late mortality

Minimally invasive cardiac surgery has allowed surgeons to perform valve procedures with a morbidity and mortality comparable with conventional resternotomy approaches while reducing postoperative ventilatory and intensive care unit requirements and overall hospital length of stay. Additionally, patient satisfaction with rapid recovery, earlier return to work, and improved cosmetic results has pushed the pendulum of reoperative valve surgery towards minimally invasive techniques. We reviewed our institutional data consisting of 129 patients requiring reoperative valve surgery over the past 4 years, which was accomplished using these minimally invasive approaches