To determine the incidence and extent of calcification of implanted glutaraldehyde-treated porcine prosthetic heart valves, 82 valves explanted from 73 patients were examined for calcium by radiography and light microscopy. At the time of valve implantation, the patients were 2 1/4-76 years old. The included 15 children (patients younger than 15 years of age, mean age at time of valve implantat...

The aortic valve, located between the left ventricle and the aorta, allows for unidirectional blood flow, preventing backflow into the ventricle. Aortic valve leaflets are composed of interstitial cells suspended within an extracellular matrix (ECM) and are lined with an endothelial cell monolayer. The valve withstands a harsh, dynamic environment and is constantly exposed to shear, flexion, te...

PURPOSE We reviewed the literature to better elucidate the history behind our understanding of the anatomy, classification and embryology of posterior urethral valves. MATERIALS AND METHODS A directed MEDLINE literature review of the anatomy, classification and embryology of posterior urethral valves was performed. An effort was made to focus on the most frequently cited historical articles a...

Conventional biological heart valves treated with glutaraldehyde (GA) reveal a limited lifespan due to calcification. This is assumed to be an immune response initiated process, which is not seen with decellularized valves. However, their immunological potential is still a matter of debate. Therefore, serum samples from patients undergoing heart valve surgery were obtained before (Pre), after (...

Background. Although our comprehension of nonrheumatic aortic stenosis (NRAS) has increased substantially during the last decade, less is known about the histopathology of rheumatic aortic stenosis (RAS). The aim of this study was to investigate rheumatic aortic stenosis by means of analyses previously used in nonrheumatic stenosis. Material and Methods. Valve specimens were obtained from 39 pa...

BACKGROUND Minimal data exist on the long-term survival of dialysis patients after cardiac valve surgery. Current practice guidelines of the American College of Cardiology/American Heart Association Task Force on the management of patients with valvular heart disease proscribe the use of bioprosthetic (tissue) valves in hemodialysis patients. METHODS AND RESULTS Dialysis patients hospitalized...

BACKGROUND Rheumatic heart disease is the most common cause of valvular disease in developing countries. Despite the high prevalence of this disease, the cellular mechanisms are not well known. We hypothesized that rheumatic valve calcification is associated with an osteoblast bone formation and neoangiogenesis. METHODS AND RESULTS To test this hypothesis, we examined human rheumatic valves r...

It has been estimated that up to 7,000 patients with Björk-Shiley Delrin (BSD) heart valves may be alive as of January 1996, the range of implant durations being from 15 to 27 years. The clinical question was whether these BSD valves could be expected to continue to function satisfactorily or if prophylactic replacement might be warranted. The data presented in this supplement suggest that clin...

The past 50 years have witnessed remarkable progress in the development of safe, hemodynamically favorable mechanical heart valves. Starr-Edwards aortic and mitral ball valves introduced in the mid-1960s, continue to be used successfully worldwide. More than 100,000 Omniscience and Omnicarbon tilting-disc valves have been implanted since 1978 with essentially no mechanical failure; similar resu...

BACKGROUND AND AIM OF THE STUDY Glutaraldehyde-preserved bioprosthetic heart valves are non-viable and have a limited durability because of calcification, tissue wear, and inflammation, especially in children. Decellularized porcine heart valves, when treated with deoxycholic acid (DOA), have exhibited complete recellularization and an absence of calcification when implanted into the pulmonary ...