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Pulmonary Valve (pulmonary + valve)

Distribution by Scientific Domains

Medical Sciences	100%

Terms modified by Pulmonary Valve

pulmonary valve replacement

pulmonary valve stenosis

Selected Abstracts

Pacemaker Lead Prolapse through the Pulmonary Valve in Children

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 10 2007
CHARLES I. BERUL M.D.
Background:Transvenous pacemaker leads in children are often placed with redundant lead length to allow for anticipated patient growth. This excess lead may rarely prolapse into the pulmonary artery and potentially interfere with valve function. We sought to determine the response to lead repositioning on pulmonary valve insufficiency. Methods:Retrospective reviews of demographics, lead type, implant duration, and radiography and echocardiography. Results:A total of 11 pediatric patients were identified with lead prolapse through the pulmonary valve, of which nine patients underwent procedures to retract and reposition the lead (age at implant 9 ± 4 years, age at revision 13 ± 4 years). The implant duration prior to revision was 4 ± 3 years. Two leads required radiofrequency extraction sheaths for removal, two pulled back using a snare, while five leads were simply retracted and repositioned. Tricuspid regurgitation was none/trivial (three), mild (four), or moderate (two) and only two improved with repositioning or replacement. Pulmonary regurgitation preoperatively was mild (three), mild-moderate (two), or moderate (four) compared with trivial (three), mild (four), and moderate (two) after revision. Patients with longer-term implanted leads had less improvement in pulmonary insufficiency. Two patients had mild pulmonary stenosis from lead-related obstruction. Conclusions:Prolapse of transvenous pacing leads into the pulmonary artery can occur when excess slack is left for growth. Leads can often be repositioned, but may require extraction and replacement, particularly if chronically implanted and adherent to valve apparatus. Lead revision does not always resolve pulmonary insufficiency, potentially leaving permanent valve damage. [source]

Two-Dimensional Echocardiographic Findings of Pulmonary Valve Cyst Secondary to Pulmonary Valvuloplasty

ECHOCARDIOGRAPHY, Issue 7 2009
Harvinder Dod M.D.
Real time two-dimensional transthoracic and transesophageal echocardiography demonstrated a mobile echolucent mass attached to the pulmonary valve in a 25-year-old adult, 20 years following balloon pulmonary valvuloplasty. The mass was surgically excised and pathology showed it to be a cyst. [source]

Minimally Invasive Transventricular Implantation of Pulmonary Xenograft

JOURNAL OF CARDIAC SURGERY, Issue 4 2008
Howaida Al Qethamy F.R.C.S., M.D.
A number of ingenious techniques have been described for percutaneous aortic and pulmonary valve replacement as well as transventricular aortic valve replacement. We describe a technique for transventricular pulmonary valve replacement utilizing off-the-shelf bovine tissue valve, vascular stents, and simplified delivery system. After median sternotomy with limited exposure of the right ventricle, Contegra 200 pulmonary valve (Medtronic, Inc., Minneapolis, MN, USA) is transfixed inside a CP stent (NuMed, Inc., Hopkinton, NY, USA) using multiple 5/0 prolene sutures. The valve/stent composite is crimped on a Cristal balloon catheter (Balt, Montmorency, France). The valve/stent and the balloon are then introduced via a small purse-string placed at the RVOT. The stent/valve composite is then expanded in the pulmonary valve position. [source]

Mid-term Results of the Ross Procedure

JOURNAL OF CARDIAC SURGERY, Issue 4 2001
Domenico Paparella M.D.
Although the Ross procedure has been performed for over three decades, its role in the management of patients with aortic valve disease is not well established. This study reviews our experience with this operation. From 1990 to 1999, 155 patients underwent the Ross procedure. The mean age of 106 men and 49 women was 35 years. Most patients (85%) had congenital aortic valve disease. The pulmonary autograft was implanted in the subcoronary position in 2 patients, as an aortic root inclusion in 78, and aortic root replacement in 75. The follow-up extended from 9 to 114 months, mean of 45 ± 28 months, and it was complete. All patients have had Doppler echocardiographic studies. There was only one operative and one late death. The survival was 98% at 7 years. The freedom from 3+ or 4+ aortic insufficiency was 86% at 7 years and the freedom from reoperation on the pulmonary autograft was 95% at 7 years. Dilation of the aortic annulus and/or sinotubular junction was the most common cause of aortic insufficiency. One patient required three reoperations on the biological pulmonary valve. Most patients (96%) have no cardiac symptoms. The Ross procedure has provided excellent functional results in most patients, but progressive aortic insufficiency due to dilation of the aortic annulus and/or sinotubular junction is a potential problem in a number of patients. [source]

Radiofrequency Catheter Ablation of Idiopathic Ventricular Tachycardia Originating in the Main Stem of the Pulmonary Artery

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 3 2002
CARL TIMMERMANS M.D.
Idiopathic Pulmonary Artery Ventricular Tachycardia. We report the case of a patient in whom successful radiofrequency catheter ablation of an idiopathic ventricular tachycardia (VT) originating in the main stem of the pulmonary artery was performed. After successful ablation of the index arrhythmia, which was an idiopathic right ventricular outflow tract VT, a second VT with a different QRS morphology was reproducibly induced. Mapping of the second VT revealed the presence of myocardium approximately 2 cm above the pulmonary valve. Application of radiofrequency energy at this site resulted in termination and noninducibility of this VT. After 6-month follow-up, the patient remained free from VT recurrences. [source]

Cardiac outcomes of hydrops as a result of twin,twin transfusion syndrome treated with laser surgery

JOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 1-2 2009
Peter H Gray
Aim: To determine cardiac outcomes of foetal hydrops as a result of twin,twin transfusion syndrome treated with laser surgery. Methods: Hydrops identified in 16 recipient foetuses with twin,twin transfusion syndrome was treated with laser ablation surgery to anastomotic vessels. Prior to laser surgery, the foetuses were assessed by echocardiography for cardiac abnormalities and ventricular and valvular dysfunction. After delivery, echocardiography was performed on 15 of the 16 newborn infants. Results: Foetal echocardiography indicated impaired biventricular function in the 16 hydropic foetuses. Five foetuses had little or no forward flow through the pulmonary valve, while four had pulmonary regurgitation. Following laser surgery performed at a mean of 22.9 weeks gestation, hydrops resolved in all cases. Delivery occurred at a mean of 33.6 weeks gestation. Post-natal echocardiography revealed cardiac abnormalities in five neonates, of whom three had right ventricular outflow tract obstruction. One preterm infant with severe pulmonary stenosis died with intractable cardiac failure. Conclusion: The majority of hydropic infants with twin,win transfusion syndrome have normal cardiac outcomes following intrauterine laser surgery. As up to one-third may have cardiac abnormalities, cardiological monitoring is recommended during the first year of life. [source]

Pacemaker Lead Prolapse through the Pulmonary Valve in Children

Tissue Engineering of Heart Valves In Vivo Using Bone Marrow-derived Cells

ARTIFICIAL ORGANS, Issue 7 2006
Sang-Soo Kim
Abstract:, In this study, we tissue-engineered heart valves in vivo using autologous bone marrow-derived cells (BMCs). Canine BMCs were differentiated into endothelial cell (EC)-like cells and myofibroblast (MF)-like cells. Decellularized porcine pulmonary valves were seeded with BMCs and implanted to abdominal aorta and pulmonary valve of bone marrow donor dogs. Histological examination of the explants identified the regeneration of valvular structures expressing CD31 and smooth muscle ,-actin, indicating the presence of EC-like and MF-like cells in the grafts at 3 and 1 week, respectively, after implantation. Fluorescent microscopic examinations identified the presence of fluorescently labeled cells in the explants, indicating that the implanted BMCs survived and participated in the heart valve reconstitution. This study reports, for the first time, on tissue engineering of heart valve in vivo using BMCs. [source]

Tissue Engineered Heart Valves: Autologous Cell Seeding on Biodegradable Polymer Scaffold

ARTIFICIAL ORGANS, Issue 5 2002
Toshiharu Shinoka
Abstract: We previosly reported on the successful creation of tissue-engineered valve leaflets and the implantation of these autologous tissue leaflets in the pulmonary valve position. Mixed cell populations of endothelial cells and fibroblasts were isolated from explanted ovine arteries. Endothelial cells were selectively labeled with an acetylated low-density lipoprotein marker and separated from fibroblasts using a fluorescent activated cell sorter. A synthetic biodegradable scaffold consisting of polyglycolic acid fibers was seeded first with fibroblasts then subsequently coated with endothelial cells. Using these methods, autologous cell/polymer constructs were implanted in 6 animals. In 2 additional control animals, a leaflet of polymer was implanted without prior cell seeding. In each animal, using cardiopulmonary bypass, the right-posterior leaflet of the pulmonary valve was resected completely and replaced with an engineered valve leaflet with (n = 6) or without (n = 2) prior cultured cell seeding. After 6 h and 1, 6, 7, 9, and 11 weeks, the animals were sacrificed and the implanted valve leaflets were examined histologically, biochemically, and biomechanically. Animals receiving leaflets made from polymer without cell seeding were sacrificed and examined in a similar fashion after 8 weeks. In the control animals, the acellular polymer leaflets were degraded completely leaving no residual leaflet tissue at 8 weeks. The tissue-engineered valve leaflet persisted in each animal in the experimental group; 4-hydroxyproline analysis of the constructs showed a progressive increase in collagen content. Immunohistochemical staining demonstrated elastin fibers in the matrix and factor VIII on the surface of the leaflet. The cell labeling experiments demonstrated that the cells on the leaflets had persisted from the in vitro seeding of the leaflets. In the tissue-engineered heart valve leaflet, transplanted autologous cells generated proper matrix on the polymer scaffold in a physiologic environment at a period of 8 weeks after implantation. [source]

Noninvasive Assessment of Influence of Resistant Respiration on Blood Flow Velocities Across the Cardiac Valves in Humans,A Quantification Study by Echocardiography

ECHOCARDIOGRAPHY, Issue 5 2004
Lijun Yuan M.D.
The aim of our study is to quantitatively investigate influence of the intrathoracic pressure change on the four cardiac valves' velocities and further verify a new proposal of the mechanism of respiratory influence on hemodynamics. Methods: Thirty healthy volunteers with no cardiopulmonary diseases were included. The intrathoracic pressure changes were measured with self-designed device. The velocity across the four cardiac valves during spontaneous respiration and with the intrathoracic pressure change at ,4, ,8, and ,12 mmHg, respectively, were recorded simultaneously with the electrocardiogram and respiratory curve. The respiratory variation indices (RVIs) were calculated. The average RVIs of mitral, aortic, tricuspid, and pulmonary valves were 12.54%, 13.19%; 6.23%, 8.27%; 20.27%, 24.36%; and 6.45%, 7.69% with intrathoracic pressure change at ,8 mmHg and ,12 mmHg, respectively. All the above parameters have a significant difference from those during spontaneous respiration (P < 0.01 or P < 0.001). We concluded that it might be the respiratory intrathoracic pressure change that causes the change of the velocity across the valves. (ECHOCARDIOGRAPHY, Volume 21, July 2004) [source]

Estimation of pulse wave velocity in main pulmonary artery with phase contrast MRI: Preliminary investigation

JOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 6 2006
Hsu-Hsia Peng MS
Abstract Purpose To assess the feasibility and reproducibility of a noninvasive MRI method to measure pulse wave velocity (PWV) in the main pulmonary artery (MPA). Materials and Methods A total of 17 subjects without history of pulmonary diseases (38.2 ± 18.4 years) participated in this study. Series of MR velocity maps of the MPA were acquired at 2 cm above the pulmonary valves using a two-dimensional phase-contrast sequence. Effective temporal resolution was 11 msec after interleaving two dynamic series with different values of electrocardiograph (ECG) trigger delay. PWV was derived as the rate of MPA flow variations per unit change in MPA cross-sectional area, during early systole. Seven healthy subjects underwent three repetitive examinations to investigate intrascan and interscan reproducibility. Results Flow vs. area was highly linear in the MPA during early systole, with Pearson's coefficients ranging from 0.982 to 0.999, rendering derivation of PWV with little difficulty. Average value of PWV in MPA was 1.96 ± 0.27 m/second, in good agreement with literature values measured using invasive means. The percentage intra- and interscan differences were 5.46% and ,10.86%, respectively. Conclusion Phase-contrast MRI to noninvasively measure PWV in the MPA is feasible with good reproducibility. J. Magn. Reson. Imaging 2006. © 2006 Wiley-Liss, Inc. [source]

Detergent Decellularization of Heart Valves for Tissue Engineering: Toxicological Effects of Residual Detergents on Human Endothelial Cells

ARTIFICIAL ORGANS, Issue 3 2010
Serghei Cebotari
Abstract Detergents are powerful agents for tissue decellularization. Despite this, the high toxicity of detergent residua can be a major limitation. This study evaluated the efficacy of detergent removal from decellularized pulmonary valves (PVs) and the consequences of repopulation with human endothelial cells (HECs). Porcine PVs were treated with 1% sodium deoxycholate (SDC), group A; 1% sodium dodecyl sulfate (SDS), group B; and a mixture of 0.5% SDC/0.5% SDS, group C (n = 5 each). After each of 10 succeeding wash cycles (WCs), samples of the washing solution (WS) were analyzed by solid phase extraction and high performance liquid chromatography for the presence of detergents. Metabolic activity of HEC was also assessed in the WS samples (cytotoxicity and MTS assays). Decellularized and washed PVs were reseeded with HEC. Histological analysis demonstrated efficient tissue decellularization in all groups. Detergents' concentration in all WSs decreased exponentially and was below 50 mg/L after 6, 8, and 4 WCs in groups A, B, and C, respectively. This concentration resulted in no significant toxic influence on cell cultures, and scaffolds could be efficiently reseeded with HEC. In conclusion, intensive washing of detergent decellularized valvular scaffolds lowers the residual contamination below a hazardous threshold and allows their successful repopulation with HEC for tissue engineering purposes. [source]