fibrin and Cardiomyopathies

Reduction of biomaterial calcification is an important aim in the basic research of biological heart valves. An in vitro model was used to investigate the influence of serum calcium concentration and surface coverage with cells or basal proteins on calcium uptake of bovine pericardium.. Samples of glutaraldehyde-tanned bovine pericardium, stored in formaldehyde and detoxified with borohydride were incubated for two weeks with cell culture medium containing low (1.0 mmol/l) or physiologic (2.3 mmol Ca/l) calcium concentration. Specimens were either unseeded, completely surface-covered with rat fibrocytes (rf) or fibrin (fi), or incompletely seeded with rabbit cells (re). Quality of surface coverage was assessed by surface scanning electron microscopy and calcium content by atomic absorption spectroscopy.. Serum calcium had a significant influence on calcium uptake (low versus physiological (1.58 +/- 2.45 mg/g versus 8.10 +/- 1.73 mg/g wet wt, p < 0.001). This may explain early calcification of bioimplants in children and patients on dialysis. Surface coverage significantly reduces calcium uptake (fi, 1.20 +/- 0.41 mg/g, rf, 4.20 +/- 1.70 mg/g, p < 0.001) but complete coverage is necessary (re, 6.98 +/- 1.64 mg/g, NS).. In vitro testing of calcium uptake has proven to be a valuable tool for evaluation of biomaterial calcification.

Topics: Animals; Biocompatible Materials; Bioprosthesis; Calcinosis; Calcium; Cardiomyopathies; Cattle; Cells, Cultured; Culture Media; Disease Models, Animal; Fibrin; Heart Valve Prosthesis; Microscopy, Electron; Pericardium; Prosthesis Design; Rabbits; Rats; Reference Values; Spectrometry, Mass, Fast Atom Bombardment; Surface Properties

We have reviewed 74 cases of patients with permanent pacing, using different types of pacing leads in order to determine what morphological changes are produced by this therapy. Macroscopic examination of the heart was performed and slides at the implantation site reviewed when available. Severe chronic inflammation, scarring and a myocardial response were the prominent findings. From a strictly morphological aspect, the initial trauma at implantation time, the chronic foreign body reaction and myocardial response to chronic trauma, are both much less significant in endovenous than in epimyocardial pacing.

Topics: Abscess; Aged; Autopsy; Cardiomyopathies; Female; Fibrin; Humans; Male; Middle Aged; Myocardium; Necrosis; Pacemaker, Artificial

Topics: Africa; Autopsy; Cardiomyopathies; Cell Nucleus; Coronary Vessels; Elastic Tissue; Endocardium; Endomyocardial Fibrosis; Fibrin; Glycosaminoglycans; Heart Atria; Humans; India; Jamaica; Myocardium; Staining and Labeling

Topics: Adult; Cardiomegaly; Cardiomyopathies; Electrocardiography; Fibrin; Heart Conduction System; Heart Ventricles; Humans; Male; Radiography, Thoracic; Thromboembolism