Stentless valves are designed to reduce mechanical stress and it is hypothesized that degeneration is reduced. We report early calcification of a Sorin pericarbon stentless pericardial xenograft in aortic position leading to valve failure 2 years after valve replacement in an 11-year-old boy. Morphological evaluation of the explant revealed severe ...

Isolated pulmonic valve infective endocarditis is an uncommon clinical entity. We report our experience with three patients diagnosed with pulmonic valve endocarditis from our institution. Two cases were caused by Enterococcus faecalis (one was resistant to vancomycin) and one by coagulase-negative staphylococci (CNS). One of the cases of isolated pulmonic ...

Fungal valvular endocarditis is an unusual cause of endocarditis, yet very important because of its historically poor prognosis. We report two fatal cases of fungal valvular endocarditis following cardiovascular surgery, presenting as femoral artery embolism. Aspergillus terreus and A. flavus were the causative agents of endocarditis in the two patients. ...

Modern chitons (Mollusca: Polyplacophora) possess a highly conserved skeleton of eight shell plates (valves) surrounded by spicules or scales, and fossil evidence suggests that the chiton skeleton has changed little since the first appearance of the class in the Late Cambrian period (about 500 million years before present, Myr bp). ...

BACKGROUND: Prosthetic valve thrombosis is a life-threatening complication. We reviewed the incidence, risk factors, and treatment strategies of this rare complication. METHODS: From February 1981 through January 2001, 5430 valve operations were performed in 4924 patients at the Montreal Heart Institute. Of this cohort, 39 patients presented with prosthetic valve ...

BACKGROUND: The nasal valve region has remained difficult to define in clinical practice in part because of lack of integration between physiological data and anatomic-surgical findings. METHODS: In this review, we summarize the anatomic, physiological, and imaging data regarding this complex area of airflow regulation. RESULTS: There is no singular ...

BACKGROUND AND AIM OF THE STUDY: An in-vitro technique has been developed to assess the flow-induced thrombosis of artificial heart valves, using renneted milk as a blood analog. Previous studies have demonstrated similarities between the clotting of blood and milk on both microscopic and macroscopic scales. The study aim was ...

A fastidious gram-negative bacterium was isolated from the blood of a 37-year-old man who had insidious endocarditis with a sudden rupture of a cerebral aneurysm. Characterization of the organism through phylogenetic and phenotypic analyses revealed a novel species of Cardiobacterium, for which the name Cardiobacterium valvarum sp. nov. is proposed. ...

OBJECTIVE: We sought to compare the long-term clinical outcomes of patients who underwent isolated aortic valve replacement with single-disc and bileaflet mechanical heart valves. METHODS: From May 1975 through October 2001, 590 single-disc valves (7 models) were used for isolated valve replacement, and from November 1980 through July 2002, 1283 ...

OBJECTIVES: We report our initial experience with percutaneous pulmonary valve replacement in animals with large pulmonary trunks, using a modified percutaneous approach. BACKGROUND: Percutaneous pulmonary valve replacement has recently been introduced, and early clinical experience has been reported. This technique is presently limited to patients with a right ventricular outflow ...

OBJECTIVE: To attempt to reconcile reports containing contradictory findings with the St. Jude Medical Silzone heart valve. METHODS: Major leak and thromboembolism data were extracted from available Silzone valve studies. Linearized rates were used to summarize and compare the events rates among the studies. RESULTS: The Artificial Valve Endocarditis Reduction ...

OBJECT: Surveys of cerebrospinal fluid (CSF) shunts that have been removed from patients have shown that even when the ventricular catheter is the cause of the obstruction, the valve may be obstructed or underperforming. The aim of this pilot study was to investigate the degradation of shunt valve structure over ...

A 68-year old man with fever chills and a diastolic murmur was diagnosed with aortic-valve endocarditis caused by coagulase-negative Staphylococcus lugdunensis. The clinical condition initially improved with antibiotic therapy. On day seven, transoesophageal echocardiography revealed large abscesses extending from the aortic root to the left ventricular wall. Emergency cardiac surgery ...

Hemodynamically significant systemic-to-pulmonary artery collaterals may represent an underappreciated cause of cardiorespiratory compromise in tetralogy of Fallot with absent pulmonary valve (TOF/APV). We retrospectively reviewed the angiographic, magnetic resonance imaging, operative, and autopsy reports of the 50 patients with TOF/APV managed at our institution in the past 10 years and ...

BACKGROUND: Tissue degeneration and calcification are the two chief obstacles to the successful application of bioprosthetic heart valves. To enable the study of the durability of bioprosthetic heart valves and the efficacy of anti-calcification treatment, it has become necessary to develop animal models. The aim of this study is to ...

BACKGROUND: The purpose of this study was to perform midterm evaluation of the clinical performance of the Sorin Bicarbon mechanical heart valve prosthesis. METHODS: From November 1992 to December 2002, 328 patients underwent isolated aortic (AVR; 156) or mitral (MVR; 172) valve replacement with the Sorin Bicarbon mechanical valve. Concomitant ...

The objective of this study was to develop a pre-clinical large animal model for the in vivo hemodynamic testing of prosthetic valves in the aortic position without the need for cardiopulmonary bypass. Ten male pigs were used. A composite valved conduit was constructed in the operating room by implanting a ...

A prospective study was performed (June 1999 to May 2001) to determine the incidence of infective endocarditis (IE) due to Bartonella in dogs in northern California and to compare these patients with other dogs with IE. IE was diagnosed antemortem based on clinical signs and echocardiography in 18 dogs. The ...

To examine whether an accumulation of Ca in the tissues was accompanied by an increase of Mg, the authors investigated the relationships between Ca and Mg contents in the common iliac arteries, aortic valves, xiphoid processes, costal cartilages, posterior longitudinal ligaments, trigeminal nerves, and ribs by inductively coupled plasma-atomic emission ...

BACKGROUND AND OBJECTIVES: The prognosis for infants with pulmonary atresia and intact ventricular septum (PA/IVS) is poor and they present a major management challenge. Mechanical penetration of the atretic pulmonary valve is an applicable option for decompression of the right ventricle and optimization of left ventricular function. The utilization of ...

Prorocentrum lima (Ehrenberg) Dodge, one of the cosmopolitan dinoflagellates, is basically benthic and is found on the surface of macroalgae and detritus. The identification of this species requires detailed morphological observation because of its close similarity to other benthic Prorocentrum species. The purpose of this study is to detect the ...

It is commonly believed that venous valves are not present in veins smaller than 2 mm in diameter. Venous valves, however, have been identified recently in small veins in several regions of the body. This study was undertaken to determine the size distribution of venous valves in the human lower ...

Epididymo-orchitis is an uncommon complication of imperforate anus. A 14-year-old boy who received surgical repair for imperforate anus was diagnosed with right epididymo-orchitis. Intravenous pyelography showed a right solitary kidney. Posterior urethral valve, reflux of contrast medium to the ejaculatory duct and incomplete duplicate urethra were suspected from voiding cystourethrography. ...

Replacement of the native pulmonary valve (PV) with tissue engineered valves requires a thorough understanding of the function of the PV. We undertook the following study to quantify the biaxial mechanical behavior of the porcine PV and develop a structural constitutive model. To our knowledge, this is the first such ...

Recently, cavitation on the surface of mechanical heart valves (MHVs) has been studied as a cause of fractures occurring in implanted MHVs. In the present study, we investigated the mechanism of MHV cavitation associated with the Björk-Shiley valve and the Medtronic Hall valve in an electrohydraulic total artificial heart (EHTAH). ...

A 10-year-old girl underwent tetralogy of Fallot (TOF) repair and subsequent pulmonary valve replacement with a St. Jude Medical mechanical heart valve prosthesis. Valve replacement was necessary due to right heart failure resulting from pulmonary regurgitation occurring three months after TOF repair. At the age of 25 years, when she ...

The requieniid rudist species ‘Matheronia’ salevensis FAVRE, first described from the Tithonian of Mont Saleve, eastern France, is transferred to the genus Hypelasma PAQUIER, which is distinguished from Matheronia by possession of a posterior myophoral ledge in the left (attached) valve. Diminutive specimens from the Upper Kimmeridgian of the southern ...

Creation of a competent pulmonary monocusp valve facilitates transition from pressure to volume overload following right ventricular outflow tract reconstruction. To determine intermediate-term results and performance of the different types of polytetrafluoroethylene membrane used to construct monocusp valves and transannular patches, 12 infant lambs underwent excision of the native pulmonary ...

Heart valve surgery continues to evolve in a dynamic fashion. While the exact role of minimally invasive approaches still needs to be defined, progress has been made in the development of new bioprostheses and their durability. Most importantly, valve repair has been standardized for the mitral and introduced for the ...

OBJECTIVE: Cardiovascular tissue engineering is a novel concept to develop ideal heart valve substitutes. The objective of this study was to use decellularized porcine pulmonary valves, ovine cells and dynamic tissue culture to obtain viable and biomechanically stable constructs, resembling native aortic heart valves. METHODS: Endothelial cells and myofibroblasts were ...

BACKGROUND: Mechanical bileaflet valves with enhanced inner diameter may offer superior hemodynamic properties in patients with a small aortic annulus. The aim of this clinical study was to compare these valves with standard bileaflet prostheses in vivo. METHODS: Mechanical aortic valve replacement for combined stenosis and regurgitation was performed in ...

A 47-year-old male patient died unexpectedly 10 years after replacement of the aortic valve with a Carbomedics heart valve prosthesis required for post-endocarditic valve stenosis. The man was in regular medical attendance by his general practitioner and in hospital. Clinical data and examinations did not suggest the reoccurrence of endocarditis. ...

OBJECTIVE: Acellularized porcine heart valve scaffolds have been successfully used for heart valve tissue engineering, creating living functioning heart valve tissue. However, there is concern about the possibility of porcine endogenous retrovirus transmission. In this study we investigated whether acellularized porcine heart valve scaffold causes cross-species transmission of porcine endogenous ...

BACKGROUND AND OBJECTIVE: We aimed to develop a clinical prediction rule for 30-day mortality in patients undergoing Björk-Shiley convexo-concave (BScc) valve replacement, based on primary valve implantation procedures. METHODS: We studied 30-day mortality in 2,263 patients who received a BScc valve between 1979 and 1985 in The Netherlands. A logistic ...

Thrombotic occlusion of a prosthetic Bjork-Shiley valve is a potentially fatal complication. We present the case of a male, 62 years of age, diagnosed with thrombotic occlusion of prosthetic Bjork-Shiley aortic valve approximately 17 years post implantation. A brief review of the literature focusing on potential risk factors associated with ...

OBJECTIVE: To determine the amount of albuterol, in various particle size ranges, delivered from a hydrofluoroalkane-propelled metered-dose inhaler (Airomir) in 3 models of pediatric intubation (ages 8 months, 4 years, and 16 years) using 4 types of aerosol reservoir: 3 spacers (ACE, AeroChamber HC MV, metal NebuChamber without 1-way valve) ...

The outside of the Arabidopsis thaliana fruit consists of three principal tissues: the valves or seedpod walls, the replum or central ridge between the valves, and the valve margins where the valves separate from the replum to disperse the seeds. Previous studies have shown that valve margin formation is specified ...

The small-intestinal submucosa square-stent bicuspid venous valve has shown the most promising results of all of the artificial venous valves developed. In long-term experimental studies in sheep, 25 valves were placed into the jugular veins and 88% exhibited good function, whereas 12% had decreased function because of valve tilting. Only ...

Malfunction of either inspiratory or expiratory check valve in a breathing circuit system may allow carbon dioxide (CO2) rebreathing and result in hypercapnia. The subsequent increase of PaCO2 may entail increased sympathetic activity which in turn causes serious problems such as tachyarrhythmia and myocardial ischemia, particularly in patients who have ...

When cavitation occurs near a material surface of a mechanical heart valve (MHV), pits on the surface of the MHV and hemolysis are caused. Therefore, it is very important to investigate the possibility of the occurrence of cavitation in an MHV. To study the possibility of cavitation occurrence in a ...

Two types of hexactinomyxon spores, Hexactinomyxon type 1 nov. and Hexactinomyxon type 2 nov., are reported from freshwater tubificid oligochaetes, Limnodrilus hoffmeisteri and L. udekemianus. Spores are triradially symmetrical and comprise a spore body, style and 6 caudal processes. The caudal processes arise from the division of each of the ...

OBJECTIVES: Nominal size remains the standard by which valves are compared, but its relationship with orifice area and the patient tissue annulus diameter may differ according to valve design. The aims of this study were to measure the orifice size and compare biologic equivalence in six bileaflet mechanical heart valve ...

The conus (bulbo-ventricular) valves of teleosts perform a key function in the control of blood backflow during ventricular diastole. However, the structural characteristics of these valves are almost unknown. This paper presents a systematic anatomical, histological and structural study of the conus valves of the adult gilthead seabream (Sparus auratus). ...

BACKGROUND: Approaches to in vivo repopulation of acellularized valve matrix constructs have been described recently. However, early calcification of acellularized matrices repopulated in vivo remains a major obstacle. We hypothesised that the matrix composition has a significant influence on the onset of early calcification. Therefore, we evaluated the calcification of ...

Prosthetic valve dysfunction (PVD) due to pannus formation is an infrequent but serious complication. A 72-year-old man who underwent aortic valve replacement was diagnosed with PVD and aneurysm of the Sinus of Valsalva. Multidetector-row computed tomography (MDCT) was used to examine the cause of PVD before reoperation. MDCT demonstrated that ...

Two patients with dysplastic pulmonary valves associated with Noonan's syndrome successfully underwent leaflet augmentation with pericardial membrane and annular enlargement with preservation of valve competence. Both patients are doing well at 36 and 37 months, respectively, postoperatively. Echocardiography and clinical assessment showed gradients of 12 and 16 mmHg, respectively, and ...

The role of low molecular weight heparin in prevention of cardio embolism is yet not proven. We report a case of rnitral and aortic prosthetic valves who had intracranial hemorrhage due to overdose of oral anticoagulation, treated with low molecular weight heparin.

BACKGROUND: Cryopreserved human heart valves are used in approximately 20% of the tissue heart valve procedures performed annually. The pathophysiology of allograft failure is not fully understood. The authors proposed the hypothesis that the rapid deterioration observed in some allograft heart valve recipients is caused by disruptive interstitial ice damage ...

PURPOSE: To ascertain if a percutaneously delivered venous valve bioprosthesis (PVVB) can be implanted in the porcine venous system and function without complications. METHODS: The PVVB is a glutaraldehyde-preserved, valve-bearing venous xenograft sutured inside a memory-coded nitinol frame (diameter 10, 12, or 14 mm). In 10 50-kg pigs, the external ...

Candida albicans endocarditis occurs mostly in patients with congenital heart disease; open heart surgery is the greatest predisposing factor. We report on a child with truncus arteriosus communis and a large Candida vegetation within the prosthetic pulmonary valve, causing severe right ventricular outflow tract obstruction. Treatment was performed successfully by ...