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Dimitris Klettas, Emma Alcock, Rafal Dworakowski, Philip MacCarthy, Mark Monaghan
AIM: The role of transoesophageal echocardiography in cardiac interventional structural procedures is well established and appreciated. However, the need for general anaesthesia (GA) throughout the procedure remains a controversial issue. The aim of the present study is to assess the feasibility and imaging quality of using a transnasal microrobe that allows the usage of conscious sedation in patients who undergo cardiac structural interventional procedures without missing the benefits, guidance and navigation of conventional trans-procedural TEE...
March 2017: Echo Research and Practice
Cesare Quarto, Simon Davies, Alison Duncan, Alistair Lindsay, Georg Lutter, Lucian Lozonschi, Neil Moat
OBJECTIVE: A small number of transcatheter mitral valve implants (TMVIs) have been reported using devices designed to treat secondary mitral regurgitation (MR). However, MR has many etiologies, and patients have a broad spectrum of annular size, geometry, and lesions. There are a number of technical challenges for TMVI including left ventricular outflow tract obstruction and paravalvular MR. Thirty days' outcome of first-in-man implants with a novel TMVI device is reported. METHODS: The Tendyne TMVI system consists of a porcine pericardial valve in a tethered nitinol frame...
May 2016: Innovations: Technology and Techniques in Cardiothoracic and Vascular Surgery
Danny Dvir, Anson Cheung, Robert Boone, Jonathon Leipsic, Philipp Blanke, Gidon Perlman, Robert Moss, Mustafa Toma, Dion Stub, Shmuel Banai, John Webb
AIMS: Transcatheter mitral valve implantation (TMVI) is a novel approach that may enable a less invasive effective reduction of mitral regurgitation (MR). A limitation of the MitraClip is that definitive implantation of a clip precludes future therapy with TMVI. The purpose of this paper is to describe contemporary treatment considerations in patients with mitral valve regurgitation. METHODS AND RESULTS: In this report we describe an attempted MitraClip implantation which resulted in no reduction of MR severity...
June 12, 2016: EuroIntervention
Samir R Kapadia, Amgad Mentias, Amr F Barakat, Mohammad Q Raza, Kanhaiya Lal Poddar, Cristian Baeza, Gabriel Maluenda, Jose Navia, Paul Schoenhagen, E Murat Tuzcu
AIM: Transcatheter mitral valve implantation (TMVI) is a novel technology for patients with severe mitral valve disease but at high surgical risk. Imaging guidance during the procedure is critical for successful device deployment. Identification of the mitral annular plane (MAP) with fluoroscopy during the procedure is limited by lack of clearly defined landmarks. We hypothesized that a plane defined by left circumflex-right coronary arteries (LCX-RCA) would have a consistent relationship to MAP...
April 2017: Catheterization and Cardiovascular Interventions
Bo Xu, Robert Gooley, Sujith K Seneviratne, Arthur Nasis
In recent years, there have been major advances in structural interventional cardiology, which have revolutionized the practice of cardiology. Appropriate selection and follow-up of patients undergoing these structural heart interventions is vital. Multi-detector computed tomography (MDCT) has emerged as a key imaging modality in the peri-procedural assessment of patients undergoing multiple structural cardiac interventions. The purpose of this review is to provide an evidence-based clinical update on the roles of MDCT in both established and evolving structural heart interventions, including transcatheter aortic valve replacement (TAVR) and transcatheter mitral valve implantation (TMVI)...
June 2016: Journal of Medical Imaging and Radiation Oncology
Rishi Puri, Omar Abdul-Jawad Altisent, Maria del Trigo, Francesco Campelo-Parada, Ander Regueiro, Henrique Barbosa Ribeiro, Robert DeLarochellière, Jean-Michel Paradis, Eric Dumont, Josep Rodés-Cabau
BACKGROUND: Transcatheter mitral valve implantation (TMVI) for severely calcified native mitral valve disease recently emerged as a treatment option in patients deemed inoperable by conventional techniques. Yet no systematic appraisal currently exists characterizing this novel treatment paradigm. METHODS: A systematic literature review summarizing the clinical, anatomical, peri- and post-procedural characteristics underscoring the technical feasibility of this procedure was performed...
February 15, 2016: Catheterization and Cardiovascular Interventions
Francesco Romeo, Valeria Cammalleri, Giovanni Ruvolo, Arshad Quadri, Pasquale De Vico, Saverio Muscoli, Massimo Marchei, Sabrina Meloni, Fabio Conti, Gian Paolo Ussia
Trans-catheter mitral valve implantation (TMVI) is actually the most attractive technique for treating patients with severe mitral regurgitation, who are denied surgical therapy. Recently, trans-catheter implantation of aortic biological prosthesis in mitral position has been done in compassionate cases, and very few experiences of TMVI in native non-calcified valves have been recently reported in very-high-risk patients, mainly with functional mitral regurgitation.Here, we report our case of TMVI using the second-generation CardiAQ prostheisis (CardiAQ Valve Technologies, Irvine, California, USA), reviewing the current state of the art...
February 2016: Journal of Cardiovascular Medicine
Philipp Blanke, Christopher Naoum, John Webb, Danny Dvir, Rebecca T Hahn, Paul Grayburn, Robert R Moss, Mark Reisman, Nicolo Piazza, Jonathon Leipsic
Transcatheter mitral valve implantation (TMVI) represents a promising approach to treating mitral valve regurgitation in patients at increased risk of perioperative mortality. Similar to transcatheter aortic valve replacement (TAVR), TMVI relies on pre- and periprocedural noninvasive imaging. Although these imaging modalities, namely echocardiography, computed tomography, and fluoroscopy, are well established in TAVR, TMVI has entirely different requirements. Approaches and nomenclature need to be standardized given the multiple disciplines involved...
October 2015: JACC. Cardiovascular Imaging
M Saxena, S S Bhunia, A K Saxena
The human histamine H2 receptor (hH2HR) is a G-protein coupled receptor protein with seven transmembrane (TM)-spanning helices primarily involved in regulation of gastric acid secretion. Antagonists targeting hH2HR are useful in the treatment of hyperacidic conditions such as peptic ulcers, gastresophageal reflux disease and gastrointestinal bleeding. We have previously reported the antagonism of 2-substituted pyrazinopyridoindoles at the human histamine H1 receptor and mode of binding of these compounds at the hH1HR using in silico methods...
2015: SAR and QSAR in Environmental Research
Darren Mylotte, Nicolo Piazza
In the last year transcatheter mitral valve implantation (TMVI) has seen a major jump in development. This technique offers the potential to treat a great number of elderly and/or high-risk patients with severe mitral regurgitation (MR). Such patients are declined surgical intervention either because the institutional Heart Team considers the risk of intervention to exceed the potential benefit, or because the patients and their families believe the morbidity of mitral surgery to be excessive. The advent of a less invasive transcatheter treatment could, therefore, potentially appeal to both clinicians and patients alike...
September 2015: EuroIntervention
Maurizio Taramasso, Francesco Maisano
Over the last few years, several surgical procedures to treat mitral regurgitation (MR) in high-risk or inoperable patients have inspired percutaneous devices, including valve repair and valve replacement technologies. As the field of transcatheter mitral valve intervention is rapidly developing, the interventional community is wondering whether valve implantation should become the leading percutaneous mitral valve therapy, and whether the introduction of reliable replacement technology will reduce the clinical value of repair approaches...
September 2015: EuroIntervention
Philipp Blanke, Danny Dvir, Christopher Naoum, Anson Cheung, Jian Ye, Pascal Thériault-Lauzier, Marco Spaziano, Robert H Boone, David A Wood, Nicolo Piazza, John G Webb, Jonathon Leipsic
BACKGROUND: We sought to determine if preprocedural CT can predict appropriate fluoroscopic angulations to achieve a coplanar view during transcatheter mitral valve implantation (TMVI) and to assess the relationship of the mitral annulus and the coronary sinus to determine the feasibility of using this as an additional landmark on fluoroscopy. METHODS: With CT, the mitral annulus was segmented in 25 patients with functional mitral regurgitation. After this, optimal projection curves were plotted and the necessary angulations for specific views parallel to the trigone-to-trigone line (TT view) and septal-to-lateral distance (SL view) were noted...
May 2015: Journal of Cardiovascular Computed Tomography
Lars Sondergaard, Matthew Brooks, Nikolaj Ihlemann, Anders Jonsson, Susanne Holme, Mariann Tang, Kim Terp, Arshad Quadri
OBJECTIVES: As many as 50% of patients with severe symptomatic mitral valve regurgitation are denied surgical valve replacement or repair due to high operative risk. We describe an early series of cases of transcatheter implantation with a CardiAQ™ mitral valve via a transapical approach. METHODS: Three consecutive patients with an Society of Thoracic Surgeons (STS) mortality score of >22% were selected for transcatheter mitral valve implantation (TMVI) on compassionate grounds...
December 2015: European Journal of Cardio-thoracic Surgery
Vinayak Bapat, Lutz Buellesfeld, Mark D Peterson, Jane Hancock, David Reineke, Chris Buller, Thierry Carrel, Fabien Praz, Ronal Rajani, Neil Fam, Han Kim, Simon Redwood, Christopher Young, Christopher Munns, Stephan Windecker, Martyn Thomas
Transcatheter aortic valve implantation (TAVI) has demonstrated the feasibility of treating valvular heart disease with transcatheter therapy. On the back of this success, various transcatheter concepts are being evaluated to treat other valvular disease, especially mitral regurgitation (MR). The concepts currently approved to treat MR replicate surgical mitral valve repair. However, most of them cannot eliminate MR completely. Similar to TAVI, a transcatheter mitral valve implantation may provide a valuable alternative...
September 2014: EuroIntervention
Ali Andalib, Samuel Mamane, Ian Schiller, Andrea Zakem, Darren Mylotte, Giuseppe Martucci, Pascal Lauzier, Waleed Alharbi, Renzo Cecere, Magdalena Dorfmeister, Ruediger Lange, James Brophy, Nicolo Piazza
AIMS: To evaluate the outcomes of mitral valve surgery in octogenarians with severe symptomatic mitral regurgitation (MR). METHODS AND RESULTS: We performed a systematic review and meta-analysis of data on octogenarians who underwent mitral valve replacement (MVR) or mitral valve repair (MVRpr). Our search yielded 16 retrospective studies. Using Bayesian hierarchical models, we estimated the pooled proportion of 30-day mortality, postoperative stroke, and long-term survival...
February 2014: EuroIntervention
Jennifer Tzeng, Brian L Lee, Brian D Sykes, Larry Fliegel
The mammalian Na(+)/H(+) exchanger isoform 1 (NHE1) resides on the plasma membrane and exchanges one intracellular H(+) for one extracellular Na(+). It maintains intracellular pH and regulates cell volume, and cell functions including growth and cell differentiation. Previous structural and functional studies on TMVI revealed several amino acids that are potentially pore lining. We examined these and other critical residues by site-directed mutagenesis substituting Asn227→Ala, Asp, Arg; Ile233→Ala; Leu243→Ala; Glu247→Asp, Gln; Glu248→Asp, Gln...
September 2011: Biochimica et Biophysica Acta
Xavier Iturrioz, Romain Gerbier, Vincent Leroux, Rodrigo Alvear-Perez, Bernard Maigret, Catherine Llorens-Cortes
Apelin is the endogenous ligand of the orphan seven-transmembrane domain (TM) G protein-coupled receptor APJ. Apelin is involved in the regulation of body fluid homeostasis and cardiovascular functions. We previously showed the importance of the C-terminal Phe of apelin 17 (K17F) in the hypotensive activity of this peptide. Here, we show either by deleting the Phe residue (K16P) or by substituting it by an Ala (K17A), that it plays a crucial role in apelin receptor internalization but not in apelin binding or in Gα(i)-protein coupling...
October 15, 2010: Journal of Biological Chemistry
Jeremiah Stitham, Scott R Gleim, Karen Douville, Eric Arehart, John Hwa
Prostacyclin plays important roles in vascular homeostasis, promoting vasodilatation and inhibiting platelet thrombus formation. Previous studies have shown that three of six cytoplasmic cysteines, particularly those within the C-terminal tail, serve as important lipidation sites and are differentially conjugated to palmitoyl and isoprenyl groups (Miggin, S. M., Lawler, O. A., and Kinsella, B. T. (2003) J. Biol. Chem. 278, 6947-6958). Here we report distinctive roles for extracellular- and transmembrane-located cysteine residues in human prostacyclin receptor structure-function...
December 1, 2006: Journal of Biological Chemistry
Songhai Chen, Fang Lin, Ming Xu, R Peter Riek, Jiri Novotny, Robert M Graham
We showed previously that Phe(303) in transmembrane segment (TM) VI of the alpha(1B)-adrenergic receptor (alpha(1B)-AR), a residue conserved in many G protein-coupled receptors (GPCRs), is critically involved in coupling agonist binding with TM helical movement and G protein activation. Here the equivalent residue, Phe(282), in the beta(2)-AR was evaluated by mutation to glycine, asparagine, alanine, or leucine. Except for F282N, which exhibits attenuated basal and maximal isoproterenol stimulation, the Phe(282) mutants display varying degrees of constitutive activity (F282L > F282A > F282G), and as shown by the results of substituted cysteine accessibility method (SCAM) studies, induce movement of endogenous cysteine(s) into the water-accessible ligand-binding pocket...
May 14, 2002: Biochemistry
Jeremiah Stitham, Kathleen A Martin, John Hwa
The human prostacyclin receptor (hIP), a G protein-coupled receptor (GPCR), plays important roles in vascular smooth muscle relaxation as well as the prevention of platelet aggregation. It has been postulated that GPCR transmembrane (TM) prolines serve as molecular hinges or swivels and are necessary for proper binding and activation. By individually (as well as collectively) mutating these hIP prolines to alanine, the ability to form key structural and functional configurations was removed. Significant effects on both binding and activation were observed...
May 2002: Molecular Pharmacology
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