Jota Nakano

Risk factors for wound infection after off-pump coronary artery bypass grafting: should bilateral internal thoracic arteries be harvested in patients with diabetes?

OBJECTIVE Wound infection is a rare but life-threatening complication after coronary artery bypass grafting. Risk factors for wound infection after off-pump bypass grafting and the validity of using bilateral internal thoracic arteries harvested in a skeletonized fashion remain unclear, especially in patients with diabetes. METHODS The data of 1500 consecutive patients having off-pump bypass grafting were prospectively collected from our database based on EuroSCORE. This cohort represents 95% of all patients undergoing coronary bypass during that period and 77% of patients undergoing off-pump bypass grafting who received bilateral internal thoracic artery grafts. Univariate and multivariate analyses were performed for patients with and without wound infection and in the diabetic subgroup. RESULTS Ninety-eight patients had wound infections: 76, impaired wound healing; 7, superficial sternal wound infection; and 12, deep sternal wound infection. Patients with wound infections had a higher prevalence of female gender, atrial fibrillation, history of congestive heart failure, chronic renal failure, peripheral vascular disease, and diabetes. Patients with a wound infection more frequently had bilateral internal thoracic artery grafting, longer operation time, longer hospital stay, and a higher mortality rate. Blood transfusions were required in 43.9% of patients with wound infections and 28.1% of those without wound infections. On logistic regression analysis, female gender and history of congestive heart failure, chronic renal failure, and diabetes mellitus were independent risk factors for wound infection. In patients with diabetes, female gender, atherosclerosis obliterans, chronic renal failure, and use of bilateral internal thoracic artery grafts were independent risk factors for wound infection. CONCLUSIONS Risk factors for wound infection after off-pump coronary artery bypass grafting are comparable with those previously reported for conventional bypass grafting. In patients with diabetes, the use of bilateral internal thoracic arteries, even when harvested in a skeletonized fashion, is a risk factor. Thus, appropriate precautions should be taken in patients with diabetes.

Midterm patency rate after saphenous vein grafting with a PAS-Port device

Recently, a new proximal anastomosis device of a saphenous vein graft (SVG) to the aorta, the PAS-Port device (Cardica, Redwood City, Calif) has been introduced and yielded encouraging results in terms of neurologic complications and early patency. However, there is a concern about the midterm (at least 1 year after surgical intervention) patency rate. The aim of this study was to evaluate the midterm patency rate of SVGs whose proximal anastomosis was performed with the PAS-Port device.

Effects of hepatocyte growth factor in myocarditis rats induced by immunization with porcine cardiac myosin

OBJECTIVES Myocarditis is considered one of the major causes of dilated cardiomyopathy. Hepatocyte growth factor (HGF) has pleiotropic activities that promote tissue regeneration and facilitate functional improvement of injured tissue. We investigated whether the epicardial sustained-release of HGF, using gelatin hydrogel sheets, improves cardiac function in a chronic myocarditis rat model. METHODS Six weeks after Lewis rats were immunized with porcine cardiac myosin to establish autoimmune myocarditis, HGF- or normal saline (NS)-incorporated gelatin hydrogel sheets were applied to the epicardium (G-HGF and G-NS, respectively). At either 2 or 4 weeks after treatment, these were compared with the Control myocarditis group. Cardiac function was evaluated by echocardiography and cardiac catheterization. Development of fibrosis was determined by histological study and expression of transforming growth factor-β1 (TGF-β1). Bax and Bcl-2 levels were measured to evaluate apoptotic activity. RESULTS At both points, fractional shortening and end-systolic elastance were higher in the G-HGF group than in the Control and G-NS groups (P < 0.01). Fractional shortening at 2 weeks of each group were as follows: 31.0 ± 0.9%, 24.8 ± 2.7% and 48.6 ± 2.6% (Control, G-NS and G-HGF, respectively). The ratio of the fibrotic area of the myocardium was lower in the G-HGF group than in the Control and G-NS groups at 2 weeks (G-HGF, 8.8 ± 0.9%; Control, 17.5 ± 0.2%; G-NS, 15.6 ± 0.7%; P < 0.01). The ratio at 4 weeks was lower in the G-HGF group than in the G-NS group (10.9 ± 1.4% vs 18.5 ± 1.3%; P < 0.01). The mRNA expression of TGF-β1 in the G-HGF group was lower than in the Control group at 2 weeks (0.6 ± 0.1 vs 1.1 ± 0.2) and lower than that in the G-NS group at 4 weeks (0.7 ± 0.1 vs 1.3 ± 0.2). The Bax-to-Bcl-2 ratios at both points were lower in the G-HGF group than in the Control group. CONCLUSIONS Sustained-released HGF markedly improves cardiac function in chronic myocarditis rats. The antifibrotic and antiapoptotic actions of HGF may contribute to the improvement. HGF-incorporated gelatin hydrogel sheet can be a new therapeutic modality for myocarditis.

Early results and problems with St. Jude medical symmetry bypass system in Japan

The early results of coronary artery grafting with an aortic connector system were assessed in Japanese patients. From May 2002 through April 2003, 24 consecutive patients underwent off-pump coronary artery bypass using an aortic connector system. Another patient was excluded because the saphenous vein was insufficient for the smallest available aortic connector system. Saphenous veins were harvested from the thigh in 17 (70.8%) patients, and from the lower leg in 7. The size of the aortic connector system was 4.5–5.0 mm in 19 (79.2%) patients. Intraoperative epiaortic echo indicated that a side-clamp was contraindicated in 15 cases. Hemostasis was instantaneous in all patients. There were no hospital deaths and no neurologic morbidity. Pre-discharge angiography revealed 100% patency of the anastomoses. Use of the aortic connector system demonstrated excellent early results with low neurologic morbidity even when employed in the context of an atheromatous ascending aorta. However, smaller sizes of the device are required for some Japanese patients.