Faculty Bibliography

BACKGROUND: This study attempts to confirm favorable results with mitral valve reconstruction (MVP) in patients greater than or equal to 70 years of age and to examine complication rates by actual analysis. METHODS: Between June of 1980 and December of 1997, 278 patients 70 years of age or older (mean, 75.2 years; range, 70 to 87 years) underwent MVP for mitral regurgitation. Most involved insertion of an annuloplasty ring. Concomitant procedures were performed in 72.3%, and 55.0% required coronary revascularization. RESULTS: For isolated MVP, the in-hospital mortality rate was 6.5% and 17.0% when combined with coronary revascularization. The mortality rate when combined with another valve procedure was 13.2%. The 5-year freedom from late cardiac death was 100% in the isolated MVP group and 79.7% for MVP with a concomitant procedure (p = 0.006). Complications were analyzed using actual (cumulative incidence) analysis to eliminate the competing risk of noncardiac death. Mean NYHA class improved from 3.32 to 1.71 postoperatively. Repair failure was rare, with a 5-year freedom from reoperation of 91.2%. CONCLUSIONS: These findings confirm the favorable outcome of MVP in elderly patients. Late repair failures are rare; comorbid disease is an important predictor of outcome

BACKGROUND: The potential for totally endoscopic mitral valve surgery has been advanced by the development of minimally invasive techniques. Recently surgical robots have offered instrument access through small ports, obviating the need for a significant thoracotomy. This study tested the hypothesis that a microsurgical robot with 5 degrees of freedom is capable of performing an endoscopic mitral valve replacement (MVR). METHODS: Dogs (n = 6) were placed on peripheral cardiopulmonary bypass; aortic occlusion was achieved with endoaortic clamping and transesophageal echocardiographic control. A small left seventh interspace 'service entrance' incision was used to insert sutures, retractor blade, and valve prosthesis. Robotically controlled instruments included a thoracoscope and 5-mm needle holders. MVR was performed using an interrupted suture technique. RESULTS: Excellent visualization was achieved with the thoracoscope. Instrument setup required 25.8 minutes (range 12 to 37); valve replacement required 69.3+/-5.39 minutes (range 48 to 78). MVR was accomplished with normal prosthetic valve function and without misplaced sutures or inadvertent injuries. CONCLUSIONS: This study demonstrates the feasibility of adjunctive use of robotic instrumentation for minimally invasive MVR. Clinical trials are indicated

BACKGROUND: The aim of this study was to examine the predictors of outcome in patients undergoing isolated valve operation using port-access techniques. METHODS: Logistic regression analysis was performed in a prospective, multi-institutional registry of patients undergoing isolated aortic valve replacement (AVR, n = 252), mitral repair (MVP, n = 491), or mitral replacement (MVR, n = 568) using port-access techniques from 1997 to 1999. RESULTS: Endoaortic balloon occlusion was used in 2% (AVR), 93% (MVP), and 90% (MVR) of cases. Conversion to full sternotomy occurred in 3.8% of all cases. For all patients, early mortality was 50 of 1,311 (3.8%) and onset of new atrial fibrillation occurred in 140 of 1,311 (11%) patients. The determinants of 30-day mortality were redo, age, and MVR or AVR. The determinants of reoperation for bleeding were age, reoperation, and MVR. Age was a predictor for stroke, and age and low or medium volume center were predictors of new atrial fibrillation. CONCLUSIONS: Excellent short-term results can be obtained using port-access techniques in isolated mitral or aortic valve operations. Patient outcome is not related to institutional case volume, and the primary determinants of outcome after port-access valve procedures are generally patient-related factors

BACKGROUND: Heparin-coated circuits reduce the inflammatory response to cardiopulmonary bypass in adult patients; however, little is known about its effects in the pediatric population. Two studies were performed to assess this technology's impact on inflammation and clinical outcomes. METHODS: In a pilot study, complement and interleukins were measured in 19 patients who had either uncoated cardiopulmonary bypass circuits or heparin-bonded circuits. Subsequently, 23 additional patients were studied in a randomized fashion. Respiratory function and blood product utilization were recorded. RESULTS: In the pilot study, heparin-bonded circuit patients had less complement 3a (p < 0.001) and interleukin-8 (p < 0.05) compared with uncoated cardiopulmonary bypass circuit patients. The randomized study revealed that the heparin-bonded circuit was associated with reduced complement 3a (p = 0.02). Multiple variable analysis revealed that the following postoperative variables were increased with bypass time (p = 0.01) and diminished with heparin-bonded circuits: interleukins (p = 0.01), peak airway pressures (p = 0.05), and prothrombin time (p = 0.03). CONCLUSIONS: Heparin-bonded circuits significantly reduce cytokines and complement during cardiopulmonary bypass and lower interleukin levels postbypass; they were also associated with improved pulmonary and coagulation function. Heparin-bonded circuits ameliorate the systemic inflammatory response in pediatric patients from cardiopulmonary bypass

BACKGROUND: Matrix metalloproteinase-2 degrades a variety of basement membrane components and is essential for tumor invasion. We have previously reported that membrane type-1 matrix metalloproteinase (MT1-MMP) cooperates with neutrophil-derived serine proteinases (NDPs; elastase, cathepsin G, protease-3) to activate matrix metalloproteinase-2. We therefore hypothesized that NDPs enhance tumor-cell invasion. METHODS: Clones of human HT1080 fibrosarcoma cells transfected with MT1-MMP sense (HT-SE) or antisense CDNA (HT-AS) were used. These cells express either high (HT-SE) or extremely low levels (HT-AS) of MT1-MMP relative to nontransfected HT1080 cells (HT-WT). The cells were incubated in the presence or absence of purified NDP, with or without alpha 1-antitrypsin or the MMP inhibitor batimastat. Cell invasion was measured with the use of Boyden chambers with polycarbonate membranes coated with a reconstituted extracellular matrix. RESULTS: Under control conditions HT-WT and HT-SE cells were 4-fold more invasive than HT-AS cells. The addition of NDP increased HT-WT and HT-SE cell invasion 60% to 100% but had no effect on HT-AS cells. alpha 1-antitrypsin or batimastat did not decrease the baseline invasiveness of HT-WT and HT-SE cells; however, they abrogated the stimulatory effect of NDP. CONCLUSIONS: HT1080 cell invasion depends on MT1-MMP expression. MT1-MMP overexpression does not increase invasiveness by itself. NDPs increase invasion by MT1-MMP expressing cells by activating matrix metalloproteinase-2

Echocardiography demonstrated an 8-cm mass adjacent to the right side of the heart in a 79-year-old man with a history of hypertension and a repaired abdominal aortic aneurysm. The results of Doppler echocardiography and magnetic resonance imaging suggested the diagnosis of an unusually large coronary artery aneurysm, and this was confirmed with coronary angiography. At surgery, the 8- to 10-cm coronary aneurysm was resected, and the patient made an uneventful recovery

OBJECTIVE: Although it has been postulated that minimally invasive cardiac surgery using the port access method would reduce operative stress and postoperative pain and accelerate postoperative recovery to a good quality of life, few data are currently available to document this intuitively appealing claim. Therefore, this study was designed to examine differences in stress response, postoperative pain, rapidity of recovery, and quality of life after port access (PA) isolated coronary artery bypass surgery compared with standard sternotomy (STD) isolated coronary bypass surgery. METHODS: Fourteen PA and 15 STD coronary bypass patients were studied postoperatively for pain score, FEV, catecholamine and cortisol levels, resumption of activity, and Duke Activity Scale ratings. The surgical approach was based on the surgeon's preference. Although the PA patients were younger, there were no other differences between the groups in gender or preoperative risk factors. RESULTS: There were no operative deaths and no differences between the groups in perioperative complications. Repeated measures analysis of variance showed lower pain scale ratings over the first 4 postoperative weeks in the PA group (P < 0.001). The PA patients also had less muscle soreness, shortness of breath, fatigue, and poor appetite at 1, 2, 4, and 8 weeks (P < 0.05), better FEV at 1 day (1.59 vs. 0.97 l/s; P < 0.02) and 3 days (2.20 vs. 1.49 l/s; P < 0.03), and lower norepinephrine levels at days 1, 2, and 3 (P = 0.005). The Duke Activity Scale questionnaire results demonstrated that more PA patients were able to walk 1-2 blocks at 1 week, climb stairs at 1 and 2 weeks, perform light or moderate housework at 1 and 2 weeks, and engage in moderate recreational activities and perform heavy housework at 4 and 8 weeks (P < 0.05). CONCLUSIONS: These results show that compared with STD coronary bypass patients PA patients enjoyed significant postoperative physiologic and quality of life advantages with less pain, less early stress response, better pulmonary function, and superior Duke Activity scores during the first 2 postoperative months