Although a significant correlation was found between blood loss and the PFA-100 IVBT, the practical value of these tests in the clinical situation is limited due to a great variability in individual results.

Our data suggest that heparinization induces platelet activation. We assume that a loss of larger and more activated platelets from the circulation contributes substantially to the platelet function defect of CPB.

Twelve patients underwent cardiac surgical procedures after having previously received irradiation of the mediastinum for various types of malignancies (Hodgkin's disease, carcinoma of the breast and seminoma). The patients' ages ranged from 39 to 69 years (mean 57 years); nine patients were female and three male. The average length of time from radiation to surgery was 15 years (3-24 years interval). The patients were divided into two groups according to the type of heart disease: Group I included seven patients who developed coronary artery disease (CAD) despite minimal risk factors. Three asymptomatic patients developed sudden myocardial infarction. In two patients the myocardial infarction was complicated (with ventricular septal defect in one and ventricular septal defect plus ventricular aneurysm in the other). All seven patients were surgically managed. Internal thoracic artery (ITA) was used in three patients as a conduit of myocardial revascularization. There were two hospital deaths in this group. The five patients in Group II underwent aortic valve replacement for aortic stenoses. Prior to the irradiation, none of the patients had a documented history of rheumatic fever, bacterial endocartitis, significant murmur, etc. There were no deaths in this group. Intraoperative findings for both groups included thickening and/or fibrosis of the ascending aortic wall, coronary arteries and aortic valve tissue. Epicardium was whitish colored and thickened.

A 62-year-old female patient with known mitral-valve prolapse for the previous five years presented with progressive dyspnea and intermittent palpitations. This clinical presentation was investigated by two-dimensional echocardiography which revealed moderate mitral regurgitation due to a pedunculated mass oscillating between the left atrium and the left ventricle. Successful operative treatment consisted of en-bloc resection of the tumor from the anterior mitral valve leaflet and its primary cords and subsequent reconstruction of the mitral valve. Pathohistological examination revealed a cystic lymphangioma originating from mitral-valve tissue. To our knowledge this is the first reported case in the literature.

The inferior epigastric artery (IEA) is a new arterial graft for myocardial revascularization. We examined the inferior epigastric artery, the internal thoracic artery (ITA) and representative sections of the coronary arteries in 45 postmortem examinations, for microscopic signs of atherosclerosis. In addition, a morphometric evaluation of the intima and media of both conduits was performed. The intima of the ITA is significantly thicker, but atherosclerosis is absent. There are fewer fenestrations/mm in the internal elastic lamina (IEL) (4.00 +/- 1.60 versus 4.62 +/- 1.46) of the IEA and the combined thickness of media and intima is lower (0.20 +/- 0.04 mm versus 0.30 +/- 0.06 mm). However, 24% of IEAs showed medial calcification of variable degrees. We conclude that the IEA should not be used routinely for myocardial revascularization until the long-term patency of this graft has been explored.