Faculty Bibliography

This report reviews the results of combined coronary bypass and Carpentier-type mitral valve reconstruction in 115 patients with ischemic mitral insufficiency. Overall operative mortality was 15.7%. Factors that increased operative risk in the overall valve repair population of 638 patients included ischemic etiology, previous cardiac surgery, NYHA functional classification, and age. Variables predicting increased risk of late cardiac death were ischemic etiology, concomitant procedures, and pulmonary hypertension. Late survival was diminished in ischemic patients, but 10-year freedom from reoperation was 93%, suggesting excellent durability after repair for ischemic mitral insufficiency. These results are compared with published reports of operative treatment for mitral insufficiency from coronary artery disease. Guidelines for use of coronary bypass alone versus coronary bypass in association with valve repair or replacement are developed. In most patients with moderate to severe mitral insufficiency secondary to coronary artery disease, the valvular pathology must be corrected, and valve repair with ring annuloplasty is the preferred method. Preoperative planning based on transesophageal echocardiography and cardiac catheterization data is essential for proper operative strategy, and attention to cardioplegia delivery and techniques to minimize reperfusion injury are necessary for optimal results. With these guidelines, late results are excellent after operative treatment for ischemic mitral insufficiency

BACKGROUND. Heparin bonding of the cardiopulmonary bypass (CPB) pump circuit decreases complement activation and fibrinolysis. It is not known whether inflammatory cytokines produced during CPB can also be modulated by the more biocompatible heparin-coated circuit. METHODS. This initial study evaluated the impact of heparin-bonded CPB circuits on production of the cytokines interleukin-1 (IL-1), tumor necrosis factor-alpha (TNF-a), IL-6, and IL-8 in adults undergoing complex cardiac operations with prolonged CPB. Twenty patients had blood samples drawn immediately before and at hourly intervals after the start of CPB using either a conventional oxygenator and circuit (n = 14) or a covalently bonded heparin oxygenator and circuit (n = 6). Levels of IL-1, TNF-a, IL-6, and IL-8 were measured in all serum samples using a 'sandwich' enzyme-linked immunosorbent assay. RESULTS. The levels of IL-6 and IL-8 increased in a time-dependent fashion in both groups, but the response was significantly less over time in the heparin-bonded group (p < 0.05) for both IL-6 and IL-8. Levels of IL-1 and TNF-a were not significantly elevated with lengthening bypass interval in either group. CONCLUSIONS. These data indicate that the use of heparin-coated bypass pump circuits results in lower serum levels of the inflammatory cytokines IL-6 and IL-8 than standard circuits. Biocompatible materials that decrease the inflammatory response to CPB may ultimately reduce the morbidity associated with cardiac operations

BACKGROUND: Recent advances in surgical techniques for the repair of left ventricular aneurysms (LVAs) include the use of an endoventricular patch to exclude the aneurysm cavity. This technique has replaced conventional linear plication of the aneurysm. The endoventricular patch technique remodels the left ventricular cavity to a more physiological geometry that improves function. METHODS AND RESULTS: From December 1989 through November 1993, 45 patients underwent an LVA repair with an endoventricular patch. This procedure was performed in association with coronary artery bypass grafting in 40 patients. Twenty-eight patients (62.2%) also had nonguided encircling subendocardial incisions. Operative procedures included 7 emergency operations, 3 concomitant valve procedures, and a mean of 2.2 bypass grafts per patient. Eight patients had previous cardiac operations. Hospital mortality was 15.6% (7/45) for all patients and 9.1% (3/33) for nonemergent revascularization and LVA repairs. Ejection fraction improved from a mean of 25.8% preoperatively to 37.8% postoperatively; the mean New York Heart Association classification improved from 3.5 to 1.5. Of patients known to have preoperative arrhythmias (inducible or sudden death), 69% were not inducible postoperatively without antiarrhythmic medication. Survival from late cardiac death (including death of unknown origin) was 86.5% at 2 years. Freedom from documented ventricular arrhythmias was 94.3% at 2 years. CONCLUSIONS: These results indicate that the patch endoaneurysmorrhaphy technique can provide an excellent functional and physiological outcome in patients with LVAs and severely impaired ventricular function

Expansion of the vascular wall through formation of neointimal fibromuscular lesions is the basic mechanism underlying stenosis of vascular grafts, restenosis of arteries treated by balloon angioplasty, and other major cardiovascular problems. This study examined the effect of a single, systemic, low dose of basic fibroblast growth factor (bFGF) on formation of neointimal fibromuscular lesions in response to injury. New Zealand white rabbits (n = 76) were subjected to balloon injury of the abdominal aorta. Forty-five rabbits were given a single intravenous dose of bFGF (0.5 microgram/kg) immediately after injury, and 31 rabbits were given only the vehicle solution as controls. After 2 (n = 15), 5 (n = 21), 14 (n = 29), or 28 (n = 11) days the rabbits were sacrificed. Those rabbits receiving the single administration of bFGF exhibited significantly greater intimal thickening (intima/media ratio) than the control group at 5 days (mean +/- standard error of the mean, 0.091 +/- 0.009 versus 0.058 +/- 0.006; p < 0.002), but not at 14 or 28 days. These results were achieved without any significant differences in mitotic indices, as determined by a mitostatic method, between the two groups at any postinjury interval examined. The findings suggest that a single systemic dose of exogenous bFGF has a relatively long term effect on enhancing the neointimal response to vascular injury. Therefore, local control of endogenous bFGF may be useful in limiting formation of vascular neointimal fibromuscular lesions, thus improving the long-term results of vascular grafts, balloon angioplasty, and other cardiovascular procedures

Aim: To document the short- and long-term effects of mitral valve reconstruction in patients 70 years of age and older. Recent favorable experience with mitral-valve reconstructive techniques has led to an attempt to apply them to elderly patients with mitral-valve defects, in the hope of improving ventricular function and freedom from complications in this higher-risk group. Methods: Between lune 1980 and June 1993, 160 consecutive mitral-valve reconstructions were performed using Carpentier techniques on patients 70 years of age and older (n=140 for 70-79 years, n=20 for greater than or equal to 80 years). All procedures were for either pure mitral regurgitation or mixed stenosis/regurgitation and involved placement of an annuloplasty ring. Concomitant cardiac operative procedures were performed in 109 patients (68%), including coronary bypass grafting in 67 (42%) and other valve procedures in 27 (17%). Results: Hospital mortality was 5.9% (three out of 51) for isolated mitral-valve reconstruction and 11.9% (19 out of 160) overall. Before surgery, 89.4% of the patients were in New York Heart Association (NYHA) class III or IV. At follow-up, 89.1% were in NYHA class I or II. In patients who underwent an isolated mitral-valve operation, cumulative freedom from cardiac death and reoperation, including hospital death, was 85.9% at 5 years. Conclusions: These results demonstrate that the encouraging results seen to date in younger patients who have undergone mitral-valve reconstruction can also be achieved in elderly patients

Sterol 27-hydroxylase activity in bovine aortic endothelial (BAE) cells in culture has been compared with that in HepG2 cells and in Chinese hamster ovary (CHO) cells using identical culture conditions. The total enzyme activity of BAE cells (3.0 nmol/72 h per mg cell protein) was comparable with that of HepG2 cells (4.0 nmol/72 h per mg protein) and both values were significantly greater than that in CHO cells (0.002 nmol/72 h per mg protein). The enzyme was identified in the mitochondria extracted from BAE cells by Western blotting using an antibody of proven specificity, and its metabolites 27-hydroxycholesterol and 3 beta-hydroxy-5-cholestenoic acid were identified by mass spectrum analysis. The presence of the enzyme in endothelium provides a mechanism for preventing accumulation of intracellular cholesterol by initiating a pathway of bile acid synthesis different from that initiated by 7 alpha-hydroxylation of cholesterol in the liver