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Sample records for bileaflet mechanical heart

  1. Effects of bileaflet mechanical heart valve orientation on coronary flow

    Science.gov (United States)

    Haya, Laura; Tavoularis, Stavros

    2015-11-01

    The aortic sinus is approximately tri-radially symmetric, but bileaflet mechanical heart valves (BMHVs), which are commonly used to replace diseased aortic valves, are bilaterally symmetric. This mismatch in symmetry suggests that the orientation in which a BMHV is implanted within the aortic sinus affects the flow characteristics downstream of it. This study examines the effect of BMHV orientation on the flow in the coronary arteries, which originate in the aortic sinus and supply the heart tissue with blood. Planar particle image velocimetry measurements were made past a BMHV mounted at the inlet of an anatomical aorta model under physiological flow conditions. The complex interactions between the valve jets, the sinus vortex and the flow in the right coronary artery were elucidated for three valve orientations. The coronary flow rate was directly affected by the size, orientation, and time evolution of the vortex in the sinus, all of which were sensitive to the valve's orientation. The total flow through the artery was highest when the valve was oriented with its axis of symmetry intersecting the artery's opening. The findings of this research may assist surgeons in choosing the best orientation for BMHV implantation. The bileaflet valve was donated by St. Jude Medical. Financial support was provided by the Natural Sciences and Engineering Research Council of Canada.

  2. Platelet activation through a Bi-leaflet mechanical heart valve

    Science.gov (United States)

    Hedayat, Mohammadali; Borazjani, Iman

    2016-11-01

    Platelet activation is one of the major drawbacks of the Mechanical Heart Valves (MHVs) which can increase the risk of thrombus formation in patients. The platelet activation in MHVs can be due to the abnormal shear stress during the systole, the backward leakage flow during the diastole, and the flow through the hinge region. We investigate the contribution of each of the above mechanism to the activation of platelets in MHVs by performing simulations of the flow through the MHV and in the hinge region. The large scale heart valve simulations are performed in a straight aorta using a sharp interface curvilinear immersed boundary method along with a strong-coupling algorithm under physiological flow conditions. In addition, in order to perform the simulation of hinge region the flow field boundary conditions are obtained from the largescale simulations during a whole cardiac cycle. In order to investigate the role of hinge flow on platelet activation in MHVs, a 23mm St. Jude Medical Regent valve hinge with three different gap sizes is tested along with different platelet activation models to ensure the consistency of our results with different activation models. We compare the platelet activation of the hinge region against the bulk of the flow during one cardiac cycle. This work is supported by the American Heart Association Grant 13SDG17220022, and the computational resources were partly provided by Center for Computational Research (CCR) at University at Buffalo.

  3. Experimental Observation on Antithrombotic Property of A New Bileaflet Mechanical Heart Valve in Sheep

    Institute of Scientific and Technical Information of China (English)

    LOU Hai-fang; XU Si-wei

    2008-01-01

    Objective: To observe the antithrombotic property of a new all-pyrolytic car-bon bileaflet mechanical heart valve so as to provide evidence for clinical practice. Meth-ods: 15 sheep underwent mitral valve replacement (MVR) with this new mechanical valve. Each animal was placed on cardiopulmonary bypass. All of the sheep were given in an anticoagulation protocol and followed for three months. Final studies were performed on all animals surviving for more than 12 weeks. Results: 10 sheep died within 48 h after op-eration, 5 sheep survived. The long-term survivors were killed for autopsies,2 sheep were killed after 1 week, 1 after 12 weeks and 2 after two and half years. Pathological examina-tion of 10 sheep which died early after operation revealed that there was neither evidence of thrombosis nor any failure of the mechanical valve. Autopsy studies in the 5 long-term survivors revealed that the sewing ring was covered by a thin layer of microthrombi consis-ted most of platelets and fibrin after 1 week. The sewing ring was covered by a tissue lay-er, with partial organized microthrombi and endothelialization after 12 weeks. Two and half years after operation, the complete endothelialization presented around the sewing ring without restriction of bileaflet motion. The tissue ingrowth tends to stop at the pyrolytic carbon-fabric interface on both surfaces of left atrium and ventricle. This study demonstra-ted that the new prosthetic heart valve had not promoted thrombosis and thrombembolism.

  4. Measurements of steady flow through a bileaflet mechanical heart valve using stereoscopic PIV.

    Science.gov (United States)

    Hutchison, Chris; Sullivan, Pierre; Ethier, C Ross

    2011-03-01

    Computational modeling of bileaflet mechanical heart valve (BiMHV) flow requires experimentally validated datasets and improved knowledge of BiMHV fluid mechanics. In this study, flow was studied downstream of a model BiMHV in an axisymmetric aortic sinus using stereoscopic particle image velocimetry. The inlet flow was steady and the Reynolds number based on the aortic diameter was 7600. Results showed the out-of-plane velocity was of similar magnitude as the transverse velocity. Although additional studies are needed for confirmation, analysis of the out-of-plane velocity showed the possible presence of a four-cell streamwise vortex structure in the mean velocity field. Spatial data for all six Reynolds stress components were obtained. Reynolds normal stress profiles revealed similarities between the central jet and free jets. These findings are important to BiMHV flow modeling, though clinical relevance is limited due to the idealized conditions chosen. To this end, the dataset is publicly available for CFD validation purposes.

  5. Vorticity dynamics of a bileaflet mechanical heart valve in an axisymmetric aorta

    Science.gov (United States)

    Dasi, L. P.; Ge, L.; Simon, H. A.; Sotiropoulos, F.; Yoganathan, A. P.

    2007-06-01

    We present comprehensive particle image velocimetry measurements and direct numerical simulation (DNS) of physiological, pulsatile flow through a clinical quality bileaflet mechanical heart valve mounted in an idealized axisymmetric aorta geometry with a sudden expansion modeling the aortic sinus region. Instantaneous and ensemble-averaged velocity measurements as well as the associated statistics of leaflet kinematics are reported and analyzed in tandem to elucidate the structure of the velocity and vorticity fields of the ensuing flow-structure interaction. The measurements reveal that during the first half of the acceleration phase, the flow is laminar and repeatable from cycle to cycle. The valve housing shear layer rolls up into the sinus and begins to extract vorticity of opposite sign from the sinus wall. A start-up vortical structure is shed from the leaflets and is advected downstream as the leaflet shear layers become wavy and oscillatory. In the second half of flow acceleration the leaflet shear layers become unstable and break down into two von Karman-like vortex streets. The onset of vortex shedding from the valve leaflets is responsible for the growth of significant cycle-to-cycle vorticity oscillations. At peak flow, the housing and leaflet shear layers undergo secondary instabilities and break down rapidly into a chaotic, turbulent-like state with multiple small-scale vortical structures emerging in the flow. During the deceleration and closing phases all large-scale coherent flow features disappear and a chaotic small-scale vorticity field emerges, which persists even after the valve has closed. Probability density functions of the leaflet position during opening and closing phases show that the leaflet position fluctuates from cycle to cycle with larger fluctuations evident during valve closure. The DNS is carried out by prescribing the leaflet kinematics from the experimental data. The computed instantaneous vorticity fields are in very good

  6. A squeeze flow phenomenon at the closing of a bileaflet mechanical heart valve prosthesis.

    Science.gov (United States)

    Bluestein, D; Einav, S; Hwang, N H

    1994-11-01

    In vivo cavitation in cardiovascular flow fields may occur under very unusual circumstances as a localized transient phenomenon which are confined to very small regions in the vicinity of the valve body or leaflet surface. The violent collapse of cavitation bubbles induces local erosion that may lead to structural damage. The fluid mechanical factors that may cause in vivo cavitation inception in mechanical heart valve (MHV) prostheses are investigated. It is established that the closing velocity of the leaflet holds the key to MHV cavitation. During the final phase of valve closing, the fluid mass in the gap space between the closing occluder and the valve's body is squeezed into motion by the rapidly approaching boundaries. The flow pattern created by this motion (termed 'squeeze flow'), is found to be related to the valve geometry, and the impact velocity of the closing leaflet. Given the closing velocity of the leaflet and the geometry of the MHV, computational flow dynamics (CFD) are made to determine the velocity distributions in the gap flow field of a bileaflet MHV in the mitral position. A two dimensional, time dependent model of the gap space show that flow velocity in the gap space can reach values as high as 30 ms-1 in regions near the edge of the inflow surface of the Edwards Duromedics (ED) MHV leaflet. This high speed stream ejected from the gap channel can create the conditions that characterize cavitation. The location of the isolated high speed region corresponds to the surface erosion that was observed in a number of damaged ED-MHV explants.

  7. Effect of heart rate on the hemodynamics of bileaflet mechanical heart valves' prostheses (St. Jude Medical) in the aortic position and in the opening phase: A computational study.

    Science.gov (United States)

    Jahandardoost, Mehdi; Fradet, Guy; Mohammadi, Hadi

    2016-03-01

    To date, to the best of the authors' knowledge, in almost all of the studies performed around the hemodynamics of bileaflet mechanical heart valves, a heart rate of 70-72 beats/min has been considered. In fact, the heart rate of ~72 beats/min does not represent the entire normal physiological conditions under which the aortic or prosthetic valves function. The heart rates of 120 or 50 beats/min may lead to hemodynamic complications, such as plaque formation and/or thromboembolism in patients. In this study, the hemodynamic performance of the bileaflet mechanical heart valves in a wide range of normal and physiological heart rates, that is, 60-150 beats/min, was studied in the opening phase. The model considered in this study was a St. Jude Medical bileaflet mechanical heart valve with the inner diameter of 27 mm in the aortic position. The hemodynamics of the native valve and the St. Jude Medical valve were studied in a variety of heart rates in the opening phase and the results were carefully compared. The results indicate that peak values of the velocity profile downstream of the valve increase as heart rate increases, as well as the location of the maximum velocity changes with heart rate in the St. Jude Medical valve model. Also, the maximum values of shear stress and wall shear stresses downstream of the valve are proportional to heart rate in both models. Interestingly, the maximum shear stress and wall shear stress values in both models are in the same range when heart rate is valve model when heart rate is >90 beats/min (up to ~40% growth compared to that of the native valve). The findings of this study may be of importance in the hemodynamic performance of bileaflet mechanical heart valves. They may also play an important role in design improvement of conventional prosthetic heart valves and the design of the next generation of prosthetic valves, such as percutaneous valves.

  8. The Application of Bileaflet Mechanical Heart Valves in the Polish Ventricular Assist Device: Physical and Numerical Study and First Clinical Usage.

    Science.gov (United States)

    Malota, Zbigniew; Sadowski, Wojciech; Krzyskow, Marek; Stolarzewicz, Bogdan

    2016-03-01

    The Polish ventricular assist device (Polvad) has been used successfully in clinical contexts for many years. The device contains two single-disc valves, one at the inlet and one at the outlet connector of the pneumatic pump. Unfortunately, in recent years, a problem has occurred with the availability of single-disc valves. This article presents the possibility of using bileaflet mechanical heart valve prostheses in the Polvad to avoid a discontinuity in clinical use. The study is based on experimental and numerical simulations and comparison of the distribution of flow, pressure, and stress (wall, shear, and turbulent) inside the Polvad chamber and the inlet/outlet connectors fitted with Sorin Monodisc and Sorin Bicarbon Fitline valves. The type and orientation of the inlet valve affects valve performance and flow distribution inside the chamber. Near-wall flow is observed for single-disc valves. In the case of bileaflet valves, the main jet is directed more centrally, with lower shear stress but higher turbulent stress in comparison with single-disc valves. For clinical usage, a 45° orientation of the bileaflet inlet valve was chosen, as this achieves good washing of the inlet area near the membrane paste surface. The Polvad with bileaflet valves has now been used successfully in our clinic for over a year and will continue to be used until new assist devices for heart support are developed.

  9. Evaluation of shear stress accumulation on blood components in normal and dysfunctional bileaflet mechanical heart valves using smoothed particle hydrodynamics.

    Science.gov (United States)

    Shahriari, S; Maleki, H; Hassan, I; Kadem, L

    2012-10-11

    Evaluating shear induced hemodynamic complications is one of the major concerns in design of the mechanical heart valves (MHVs). The monitoring of these events relies on both numerical simulations and experimental measurements. Currently, numerical approaches are mainly based on a combined Eulerian-Lagrangian approach. A more straightforward evaluation can be based on the Lagrangian analysis of the whole blood. As a consequence, Lagrangian meshfree methods are more adapted to such evaluation. In this study, smoothed particle hydrodynamics (SPH), a fully meshfree particle method originated to simulate compressible astrophysical flows, is applied to study the flow through a normal and a dysfunctional bileaflet mechanical heart valves (BMHVs). The SPH results are compared with the reference data. The accumulation of shear stress patterns on blood components illustrates the important role played by non-physiological flow patterns and mainly vortical structures in this issue. The statistical distribution of particles with respect to shear stress loading history provides important information regarding the relative number of blood components that can be damaged. This can be used as a measure of the response of blood components to the presence of the valve implant or any implantable medical device. This work presents the first attempt to simulate pulsatile flow through BMHVs using SPH method.

  10. A NUMERICAL ANALYSIS OF THE BLOOD FLOW AROUND THE BILEAFLET MECHANICAL HEART VALVES WITH DIFFERENT ROTATIONAL IMPLANTATION ANGLES

    Institute of Scientific and Technical Information of China (English)

    HONG Taehyup; KIM Chang Nyung

    2011-01-01

    The effects of implantation angles of Bileaflet Mechanical Heart Valves (BMHVs) on the blood flow and the leaflet motion are investigated in this paper.The physiological blood flow interacting with the moving leaflets ofa BMHV is simulated with a strongly coupled implicit Fluid-Structure Interaction (FSI) method based on the Arbitrary-Lagrangian-Eulerian (ALE) approach and the dynamic mesh method (remeshing) in Fluent.BMHVs are widely used to be implanted to replace the diseascd heart valves,but the patients would suffer from some complications such as hemolysis,platelet activation,tissue overgrowth and device failure.These complications are closely related to both the flow characteristics near the valves and the leaflet dynamics.The currentnumerical model is validated against a previous experimental study.The numerical results show that as the rotation angle of BMHV is increased the degree of asymmetry of the blood flow and the leaflet motion is increased,which may lead to an unbalanced force acting on the BMHVs.This study shows the applicability of the FSI model for the interaction between the blood flow and the leaflet motion in BMHVs.

  11. Blood damage through a bileaflet mechanical heart valve: a quantitative computational study using a multiscale suspension flow solver.

    Science.gov (United States)

    Min Yun, B; Aidun, Cyrus K; Yoganathan, Ajit P

    2014-10-01

    Bileaflet mechanical heart valves (BMHVs) are among the most popular prostheses to replace defective native valves. However, complex flow phenomena caused by the prosthesis are thought to induce serious thromboembolic complications. This study aims at employing a novel multiscale numerical method that models realistic sized suspended platelets for assessing blood damage potential in flow through BMHVs. A previously validated lattice-Boltzmann method (LBM) is used to simulate pulsatile flow through a 23 mm St. Jude Medical (SJM) Regent™ valve in the aortic position at very high spatiotemporal resolution with the presence of thousands of suspended platelets. Platelet damage is modeled for both the systolic and diastolic phases of the cardiac cycle. No platelets exceed activation thresholds for any of the simulations. Platelet damage is determined to be particularly high for suspended elements trapped in recirculation zones, which suggests a shift of focus in blood damage studies away from instantaneous flow fields and toward high flow mixing regions. In the diastolic phase, leakage flow through the b-datum gap is shown to cause highest damage to platelets. This multiscale numerical method may be used as a generic solver for evaluating blood damage in other cardiovascular flows and devices.

  12. Computational Simulation of Blood Flow through Bileaflet Heart Valve Prostheses

    Science.gov (United States)

    Healy, Timothy; Sotiropoulos, Fotis; Yoganathan, Ajit

    2001-11-01

    Non-physiologic flow patterns and levels of turbulence caused by contemporary bileaflet mechanical heart valve (MHV) designs are believed to be partially responsible for thromboembolic complications caused by these valves. Presently, computer-based flow assessment is not employed as a design tool. Rather, CFD is used to understand flow dynamics under highly-specialized circumstances after a design has been selected and tested experimentally. The absence of CFD from the design-screening process is most likely due to undeveloped tools specific to the heart valve problem. CFD tools for assessing MHV flow performance should be efficient at simulating the fluid-structure interaction and the resulting leaflet motion. As the first stage in the development of MHV simulation tools, a high-accuracy Chimera solver was developed and tested for laminar flow through two bileaflet MHV designs. Steady and time-dependent simulations were performed providing the highest resolution simulations of three-dimensional MHV flow fields to date. Flow structures and time-dependent flow phenomena were investigated and interpreted in the context of the clinical performance of each design studied.

  13. Effect of hinge gap width of a St. Jude medical bileaflet mechanical heart valve on blood damage potential--an in vitro micro particle image velocimetry study.

    Science.gov (United States)

    Jun, Brian H; Saikrishnan, Neelakantan; Arjunon, Sivakkumar; Yun, B Min; Yoganathan, Ajit P

    2014-09-01

    The hinge regions of the bileaflet mechanical heart valve (BMHV) can cause blood element damage due to nonphysiological shear stress levels and regions of flow stasis. Recently, a micro particle image velocimetry (μPIV) system was developed to study whole flow fields within BMHV hinge regions with enhanced spatial resolution under steady leakage flow conditions. However, global velocity maps under pulsatile conditions are still necessary to fully understand the blood damage potential of these valves. The current study hypothesized that the hinge gap width will affect flow fields in the hinge region. Accordingly, the blood damage potential of three St. Jude Medical (SJM) BMHVs with different hinge gap widths was investigated under pulsatile flow conditions, using a μPIV system. The results demonstrated that the hinge gap width had a significant influence during the leakage flow phase in terms of washout and shear stress characteristics. During the leakage flow, the largest hinge gap generated the highest Reynolds shear stress (RSS) magnitudes (~1000 N/m²) among the three valves at the ventricular side of the hinge. At this location, all three valves indicated viscous shear stresses (VSS) greater than 30 N/m². The smallest hinge gap exhibited the lowest level of shear stress values, but had the poorest washout flow characteristics among the three valves, demonstrating propensity for flow stasis and associated activated platelet accumulation potential. The results from this study indicate that the hinge is a critical component of the BMHV design, which needs to be optimized to find the appropriate balance between reduction in fluid shear stresses and enhanced washout during leakage flow, to ensure minimal thrombotic complications.

  14. High-resolution fluid-structure interaction simulations of flow through a bi-leaflet mechanical heart valve in an anatomic aorta.

    Science.gov (United States)

    Borazjani, Iman; Ge, Liang; Sotiropoulos, Fotis

    2010-02-01

    We have performed high-resolution fluid-structure interaction simulations of physiologic pulsatile flow through a bi-leaflet mechanical heart valve (BMHV) in an anatomically realistic aorta. The results are compared with numerical simulations of the flow through an identical BMHV implanted in a straight aorta. The comparisons show that although some of the salient features of the flow remain the same, the aorta geometry can have a major effect on both the flow patterns and the motion of the valve leaflets. For the studied configuration, for instance, the BMHV leaflets in the anatomic aorta open much faster and undergo a greater rebound during closing than the same valve in the straight axisymmetric aorta. Even though the characteristic triple-jet structure does emerge downstream of the leaflets for both cases, for the anatomic case the leaflet jets spread laterally and diffuse much faster than in the straight aorta due to the aortic curvature and complex shape of the anatomic sinus. Consequently the leaflet shear layers in the anatomic case remain laminar and organized for a larger portion of the accelerating phase as compared to the shear layers in the straight aorta, which begin to undergo laminar instabilities well before peak systole is reached. For both cases, however, the flow undergoes a very similar explosive transition to the small-scale, turbulent-like state just prior to reaching peak systole. The local maximum shear stress is used as a metric to characterize the mechanical environment experienced by blood cells. Pockets of high local maximum shear are found to be significantly more widespread in the anatomic aorta than in the straight aorta throughout the cardiac cycle. Pockets of high local maximum shear were located near the leaflets and in the aortic arc region. This work clearly demonstrates the importance of the aortic geometry on the flow phenomena in a BMHV and demonstrates the potential of our computational method to carry out image

  15. Laser Doppler anemometry measurements of steady flow through two bi-leaflet prosthetic heart valves

    Directory of Open Access Journals (Sweden)

    Ovandir Bazan

    2013-12-01

    Full Text Available INTRODUCTION: In vitro hydrodynamic characterization of prosthetic heart valves provides important information regarding their operation, especially if performed by noninvasive techniques of anemometry. Once velocity profiles for each valve are provided, it is possible to compare them in terms of hydrodynamic performance. In this first experimental study using laser doppler anemometry with mechanical valves, the simulations were performed at a steady flow workbench. OBJECTIVE: To compare unidimensional velocity profiles at the central plane of two bi-leaflet aortic prosthesis from St. Jude (AGN 21 - 751 and 21 AJ - 501 models exposed to a steady flow regime, on four distinct sections, three downstream and one upstream. METHODS: To provide similar conditions for the flow through each prosthesis by a steady flow workbench (water, flow rate of 17L/min. and, for the same sections and sweeps, to obtain the velocity profiles of each heart valve by unidimensional measurements. RESULTS: It was found that higher velocities correspond to the prosthesis with smaller inner diameter and instabilities of flow are larger as the section of interest is closer to the valve. Regions of recirculation, stagnation of flow, low pressure, and flow peak velocities were also found. CONCLUSIONS: Considering the hydrodynamic aspect and for every section measured, it could be concluded that the prosthesis model AGN 21 - 751 (RegentTM is superior to the 21 AJ - 501 model (Master Series. Based on the results, future studies can choose to focus on specific regions of the these valves.

  16. A finite element model on effects of impact load and cavitation on fatigue crack propagation in mechanical bileaflet aortic heart valve.

    Science.gov (United States)

    Mohammadi, H; Klassen, R J; Wan, W-K

    2008-10-01

    Pyrolytic carbon mechanical heart valves (MHVs) are widely used to replace dysfunctional and failed heart valves. As the human heart beats around 40 million times per year, fatigue is the prime mechanism of mechanical failure. In this study, a finite element approach is implemented to develop a model for fatigue analysis of MHVs due to the impact force between the leaflet and the stent and cavitation in the aortic position. A two-step method to predict crack propagation in the leaflets of MHVs has been developed. Stress intensity factors (SIFs) are computed at a small initiated crack located on the leaflet edge (the worst case) using the boundary element method (BEM). Static analysis of the crack is performed to analyse the stress distribution around the front crack zone when the crack is opened; this is followed by a dynamic crack analysis to consider crack propagation using the finite element approach. Two factors are taken into account in the calculation of the SIFs: first, the effect of microjet formation due to cavitation in the vicinity of leaflets, resulting in water hammer pressure; second, the effect of the impact force between the leaflet and the stent of the MHVs, both in the closing phase. The critical initial crack length, the SIFs, the water hammer pressure, and the maximum jet velocity due to cavitation have been calculated. With an initial crack length of 35 microm, the fatigue life of the heart valve is greater than 60 years (i.e. about 2.2 x 10(9) cycles) and, with an initial crack length of 170 microm, the fatigue life of the heart valve would be around 2.5 years (i.e. about 9.1 x 10(7) cycles). For an initial crack length greater than 170 microm, there is catastrophic failure and fatigue cracking no longer occurs. A finite element model of fatigue analysis using Patran command language (PCL custom code) in MSC software can be used to evaluate the useful lifespan of MHVs. Similar methodologies can be extended to other medical devices under cyclic

  17. Star GK Bileaflet Mechanical Valve Prosthesis-Patient Mismatch After Mitral Valve Replacement: A Chinese Multicenter Clinical Study

    Science.gov (United States)

    Cao, Hua; Qiu, Zhihuang; Chen, Liangwan; Chen, Daozhong; Chen, Qiang

    2015-01-01

    Background The aim of this study was to investigate the incidence and immediate and mid-term effects of heart valve prosthesis-patient mismatch (PPM) after mitral valve replacement using the GK bileaflet mechanical valve. Material/Methods A total of 493 cases of mechanical mitral valve replacement were performed in the departments of cardiac surgery in 7 hospitals from January 2000 to January 2008. The patients included 142 men and 351 women ages 21 to 67 (average age, 48.75). The patients were followed for 3 years after surgery. The effective orifice area index (EOAI), ≤1.2 cm2/m2, was detected during the follow-up period and was defined as PPM. The patients were assigned to either the PPM group or the non-PPM group. Finally, the preoperative, perioperative and postoperative indexes of the 2 groups of patients were compared. Results A total of 157 patients had PPM 3 years after surgery. The incidence of PPM was 31.84%. Sixty-three patients in the PPM group received a 25-mm GK bileaflet valve (40.13%), 82 received a 27-mm valve (52.23%), and 12 (7.64%) received a 29-mm valve. There were significant differences in length of intensive care unit stay, duration of ventilator use, length of hospitalization, body surface area, EOAI, mean transmitral pressure gradient, and pulmonary artery pressure between the PPM and non-PPM group (P0.05). Conclusions PPM after mitral valve replacement influences postoperative hemodynamics. Thus, larger-sized GK bileaflet mechanical valves are often used to reduce the risk of PPM. PMID:26313311

  18. Two-dimensional FSI simulation of closing dynamics of a tilting disc mechanical heart valve.

    Science.gov (United States)

    Govindarajan, V; Udaykumar, H S; Herbertson, L H; Deutsch, S; Manning, K B; Chandran, K B

    2010-03-01

    The fluid dynamics during valve closure resulting in high shear flows and large residence times of particles has been implicated in platelet activation and thrombus formation in mechanical heart valves. Our previous studies with bi-leaflet valves have shown that large shear stresses induced in the gap between the leaflet edge and the valve housing results in relatively high platelet activation levels whereas flow between the leaflets results in shed vortices not conducive to platelet damage. In this study we compare the result of closing dynamics of a tilting disc valve with that of a bi-leaflet valve. The two-dimensional fluid-structure interaction analysis of a tilting disc valve closure mechanics is performed with a fixed grid Cartesian mesh flow solver with local mesh refinement, and a Lagrangian particle dynamic analysis for computation of potential for platelet activation. Throughout the simulation the flow remains in the laminar regime and the flow through the gap width is marked by the development of a shear layer which separates from the leaflet downstream of the valve. Zones of re-circulation are observed in the gap between the leaflet edge and the valve housing on the major orifice region of the tilting disc valve and are seen to be migrating towards the minor orifice region. Jet flow is observed at the minor orifice region and a vortex is formed which sheds in the direction of fluid motion as observed in experiments using PIV measurements. The activation parameter computed for the tilting disc valve, at the time of closure was found to be 2.7 times greater than that of the bi-leaflet mechanical valve and was found to be in the vicinity of the minor orifice region mainly due to the migration of vortical structures from the major to the minor orifice region during the leaflet rebound of the closing phase.

  19. Mechanism of artificial heart

    CERN Document Server

    Yamane, Takashi

    2016-01-01

    This book first describes medical devices in relation to regenerative medicine before turning to a more specific topic: artificial heart technologies. Not only the pump mechanisms but also the bearing, motor mechanisms, and materials are described, including expert information. Design methods are described to enhance hemocompatibility: main concerns are reduction of blood cell damage and protein break, as well as prevention of blood clotting. Regulatory science from R&D to clinical trials is also discussed to verify the safety and efficacy of the devices.

  20. A biomimetic bi-leaflet mitral prosthesis with enhanced physiological left ventricular swirl restorative capability

    Science.gov (United States)

    Tan, Sean Guo-Dong; Kim, Sangho; Leo, Hwa Liang

    2016-06-01

    Mechanical heart valve prostheses are often implanted in young patients due to their durability and long-term reliability. However, existing designs are known to induce elevated levels of blood damage and blood platelet activation. As a result, there is a need for patients to undergo chronic anti-coagulation treatment to prevent thrombosis, often resulting in bleeding complications. Furthermore, recent studies have suggested that the implantation of a mechanical prosthetic valve at the mitral position results in a significant alteration of the left ventricular flow field which may contribute to flow turbulence. This study proposes a bi-leaflet mechanical heart valve design (Bio-MHV) that mimics the geometry of a human mitral valve, with the aim of reducing turbulence levels in the left ventricle by replicating physiological flow patterns. An in vitro three-dimensional particle velocimetry imaging experiment was carried out to compare the hemodynamic performance of the Bio-MHV with that of the clinically established ATS valve. The Bio-MHV was found to replicate physiological left ventricular flow patterns and produced lower turbulence levels.

  1. Role of vortices in cavitation formation in the flow at the closure of a bileaflet mitral mechanical heart valve.

    Science.gov (United States)

    Li, Chi-Pei; Chen, Sheng-Fu; Lo, Chi-Wen; Lu, Po-Chien

    2012-03-01

    Bubble cavitation occurs in the flow field when local pressure drops below vapor pressure. One hypothesis states that low-pressure regions in vortices created by instantaneous valve closure and occluder rebound promote bubble formation. To quantitatively analyze the role of vortices in cavitation, we applied particle image velocimetry (PIV) to reduce the instantaneous fields into plane flow that contains information about vortex core radius, maximum tangential velocity, circulation strength, and pressure drop. Assuming symmetrical flow along the center of the St. Jude Medical 25-mm valve, flow fields downstream of the closing valve were measured using PIV in the mitral position of a circulatory mock loop. Flow measurements were made during successive time phases immediately following the impact of the occluder with the housing (O/H impact) at valve closing. The velocity profile near the vortex core clearly shows a typical Rankine vortex. The vortex strength reaches maximum immediately after closure and rapidly decreases at about 10 ms, indicating viscous dissipation; vortex strength also intensifies with rising pulse rate. The maximum pressure drop at the vortex center is approximately 20 mmHg, an insignificant drop relative to atmospheric vapor pressures, which implies vortices play a minor role in cavitation formation.

  2. Flow visualization of a monoleaflet and bileaflet mechanical heart valve in a pneumatic ventricular assist device using a PIV system.

    Science.gov (United States)

    Lee, Hwansung; Tatsumi, Eisuke; Taenaka, Yoshiyuki

    2010-01-01

    Our group is developing a new type of pulsatile pneumatic ventricular assist device (PVAD) that uses the Medtronic Hall tilting disc valve (M-H valve). Although tilting disc valves have good washout effect inside the blood pump, they are no longer in common clinical use and may be difficult to obtain in the future. To investigate the stability of the Sorin Bicarbon valve (S-B valve) in our PVAD, we constructed a model pump made of an acrylic resin with the same configuration as our PVAD and attempted to compare the flow visualization upstream and downstream of the outlet position valve between the M-H valve and the S-B valve using a particle image velocimetry (PIV) method. The outlet S-B valve had faster closure than the M-H valve. The maximum flow velocity was greater than with the M-H valve. The maximum Reynolds shear stress (RSS) of the M-H valve reached 150 N/m(2) and that of the S-B valve reached 300 N/m(2) upstream during the end-systolic and early-diastolic phases. In both valves, the maximum RSS upstream of the valve was higher than downstream of the valve because of the regurgitation flow during valve closure. In addition, the maximum viscous shear stress reached above 2 N/m(2), which occupied only about 1%-1.5% of the maximum RSS.

  3. Developments in mechanical heart valve prosthesis

    Indian Academy of Sciences (India)

    Kalyani Nair; C V Muraleedharan; G S Bhuvaneshwar

    2003-06-01

    Artificial heart valves are engineered devices used for replacing diseased or damaged natural valves of the heart. Most commonly used for replacement are mechanical heart valves and biological valves. This paper briefly outlines the evolution, designs employed, materials being used,. and important factors that affect the performance of mechanical heart valves. The clinical performance of mechanical heart valves is also addressed. Efforts made in India in the development of mechanical heart valves are also discussed.

  4. Numerical simulation of flow in mechanical heart valves: grid resolution and the assumption of flow symmetry.

    Science.gov (United States)

    Ge, Liang; Jones, S Casey; Sotiropoulos, Fotis; Healy, Timothy M; Yoganathan, Ajit P

    2003-10-01

    A numerical method is developed for simulating unsteady, 3-D, laminar flow through a bileaflet mechanical heart valve with the leaflets fixed. The method employs a dual-time-stepping artificial-compressibility approach together with overset (Chimera) grids and is second-order accurate in space and time. Calculations are carried out for the full 3-D valve geometry under steady inflow conditions on meshes with a total number of nodes ranging from 4 x 10(5) to 1.6 x 10(6). The computed results show that downstream of the leaflets the flow is dominated by two pairs of counter-rotating vortices, which originate on either side of the central orifice in the aortic sinus and rotate such that the common flow of each pair is directed away from the aortic wall. These vortices intensify with Reynolds number, and at a Reynolds number of approximately 1200 their complex interaction leads to the onset of unsteady flow and the break of symmetry with respect to both geometric planes of symmetry. Our results show the highly 3-D structure of the flow; question the validity of computationally expedient assumptions of flow symmetry; and demonstrate the need for highly resolved, fully 3-D simulations if computational fluid dynamics is to accurately predict the flow in prosthetic mechanical heart valves.

  5. Time-Resolved Micro PIV in the Pivoting Area of the Triflo Mechanical Heart Valve.

    Science.gov (United States)

    Vennemann, Bernhard M; Rösgen, Thomas; Carrel, Thierry P; Obrist, Dominik

    2016-09-01

    The Lapeyre-Triflo FURTIVA valve aims at combining the favorable hemodynamics of bioprosthetic heart valves with the durability of mechanical heart valves (MHVs). The pivoting region of MHVs is hemodynamically of special interest as it may be a region of high shear stresses, combined with areas of flow stagnation. Here, platelets can be activated and may form a thrombus which in the most severe case can compromise leaflet mobility. In this study we set up an experiment to replicate the pulsatile flow in the aortic root and to study the flow in the pivoting region under physiological hemodynamic conditions (CO = 4.5 L/min / CO = 3.0 L/min, f = 60 BPM). It was found that the flow velocity in the pivoting region could reach values close to that of the bulk flow during systole. At the onset of diastole the three valve leaflets closed in a very synchronous manner within an average closing time of 55 ms which is much slower than what has been measured for traditional bileaflet MHVs. Hot spots for elevated viscous shear stresses were found at the flanges of the housing and the tips of the leaflet ears. Systolic VSS was maximal during mid-systole and reached levels of up to 40 Pa.

  6. 国产CL-V型双叶人工心脏瓣膜与进口St.Jude双叶瓣的临床疗效比较%Comparison on Clinical Outcomes Between China-made CL-V Bileaflet Prosthesis and St.Jude Bileaflet Prosthesis

    Institute of Scientific and Technical Information of China (English)

    祁亮; 宋兵; 刘瑞生; 唐汉博; 赵宏林; 邢旺; 高百顺

    2012-01-01

    Objective To evaluate early clinical outcomes and short-term follow-up results of CL-V bileaflet prosthesis. Methods From April 2004 to May 2010, 38 patients with valvular heart diseases underwent mechanical heart valve replacement. Eighteen patients received CL-V bileaflet valve replacement (CL group) including 8 males and 10 females with their mean age of (47. 4 ±6. 2) years and mean body weight off 64. 7±11. 9) kg. Preoperatively, 15 patients were in New York Heart Association (NYHA) class Ⅲ, and 2 patients were in NYHA class IV. Mitral valve replacement (MVR) was performed in 16patients, mitral and aortic valve replacement (DVR) in 2 patients. A total of 20 CL-V bileaflet prostheses were implanted. Twenty patients received St. Jude bileaflet valve replacement (SJM group Kncluding 9 males and 11 females with their mean age of (49. 7±7. 6) years and mean body weight of (66. 1±11. 1) kg. Preoperatively,15 patients were in NYHA class Ⅲ, and 3 patients were in NYHA class Ⅳ . MVR was performed in 17 patients, aortic valve replacement (AVR) in 1 patient, and DVR in 2 patients. A total of 22 St. Jude bileaflet prostheses were implanted. Clinical outcomes, hear function, hemodynamics and blood compatibility were measured on the 7th postoperative day and 6 months during follow-up and compared between the two groups. Results There was no early mortality ( < 30 d) or postoperative complication in either group. Follow-up rate was 100% and the mean follow-up duration was 19. 8 (6-61) months. At 6 months after surgery, those patients who were preoperatively in NYHA class Ⅲ or Ⅳall improved to class Ⅰ orⅡ. In CL group, cardiothoracic ratio was 0. 51±0. 05, left atrium diameter (44. 5±7. 8) mm, left ventricular end dias-tolic diameter (LVEDD, 46. 6±4.1) mm, LVEF 65. 3%±7. 7%, and LVFS 35. 0%±7. 1%. In SJM group, cardiothoracic ratio was 0. 51±0. 06, left atrium diameter(45. 8±9. 6)mm, LVEDD(46. 2±9. 8) mm, LVEF 64. l%+9. 0%, and LVFS 34. 9%±4. 7

  7. Mechanisms of heart failure in obesity.

    Science.gov (United States)

    Ebong, Imo A; Goff, David C; Rodriguez, Carlos J; Chen, Haiying; Bertoni, Alain G

    2014-01-01

    Heart failure is a leading cause of morbidity and mortality and its prevalence continues to rise. Because obesity has been linked with heart failure, the increasing prevalence of obesity may presage further rise in heart failure in the future. Obesity-related factors are estimated to cause 11% of heart failure cases in men and 14% in women. Obesity may result in heart failure by inducing haemodynamic and myocardial changes that lead to cardiac dysfunction, or due to an increased predisposition to other heart failure risk factors. Direct cardiac lipotoxicity has been described where lipid accumulation in the heart results in cardiac dysfunction inexplicable of other heart failure risk factors. In this overview, we discussed various pathophysiological mechanisms that could lead to heart failure in obesity, including the molecular mechanisms underlying cardiac lipotoxicity. We defined the obesity paradox and enumerated various premises for the paradoxical associations observed in the relationship between obesity and heart failure.

  8. A D-Shaped Bileaflet Bioprosthesis which Replicates Physiological Left Ventricular Flow Patterns.

    Directory of Open Access Journals (Sweden)

    Sean Guo-Dong Tan

    Full Text Available Prior studies have shown that in a healthy heart, there exist a large asymmetric vortex structure that aids in establishing a steady flow field in the left ventricle. However, the implantation of existing artificial heart valves at the mitral position is found to have a negative effect on this physiological flow pattern. In light of this, a novel D-shaped bileaflet porcine bioprosthesis (GD valve has been designed based on the native geometry mitral valve, with the hypothesis that biomimicry in valve design can restore physiological left ventricle flow patterns after valve implantation. An in-vitro experiment using two dimensional particle velocimetry imaging was carried out to determine the hemodynamic performance of the new bileaflet design and then compared to that of the well-established St. Jude Epic valve which functioned as a control in the experiment. Although both valves were found to have similar Reynolds shear stress and Turbulent Kinetic Energy levels, the novel D-shape valve was found to have lower turbulence intensity and greater mean kinetic energy conservation.

  9. Fluid mechanics of artificial heart valves.

    Science.gov (United States)

    Dasi, Lakshmi P; Simon, Helene A; Sucosky, Philippe; Yoganathan, Ajit P

    2009-02-01

    1. Artificial heart valves have been in use for over five decades to replace diseased heart valves. Since the first heart valve replacement performed with a caged-ball valve, more than 50 valve designs have been developed, differing principally in valve geometry, number of leaflets and material. To date, all artificial heart valves are plagued with complications associated with haemolysis, coagulation for mechanical heart valves and leaflet tearing for tissue-based valve prosthesis. For mechanical heart valves, these complications are believed to be associated with non-physiological blood flow patterns. 2. In the present review, we provide a bird's-eye view of fluid mechanics for the major artificial heart valve types and highlight how the engineering approach has shaped this rapidly diversifying area of research. 3. Mechanical heart valve designs have evolved significantly, with the most recent designs providing relatively superior haemodynamics with very low aerodynamic resistance. However, high shearing of blood cells and platelets still pose significant design challenges and patients must undergo life-long anticoagulation therapy. Bioprosthetic or tissue valves do not require anticoagulants due to their distinct similarity to the native valve geometry and haemodynamics, but many of these valves fail structurally within the first 10-15 years of implantation. 4. These shortcomings have directed present and future research in three main directions in attempts to design superior artificial valves: (i) engineering living tissue heart valves; (ii) development of advanced computational tools; and (iii) blood experiments to establish the link between flow and blood damage.

  10. Mechanical circulatory treatment of advanced heart failure

    DEFF Research Database (Denmark)

    Løgstrup, Brian B; Vase, Henrik; Gjedsted, Jakob;

    2016-01-01

    Heart failure is one of the most common causes of morbidity and mortality worldwide. When patients cease to respond adequately to optimal medical therapy mechanical circulatory support has been promising. The advent of mechanical circulatory support devices has allowed significant improvements...... in patient survival and quality of life for those with advanced or end-stage heart failure. We provide a general overview of current mechanical circulatory support devices encompassing options for both short- and long-term ventricular support....

  11. Mechanical signaling coordinates the embryonic heart

    Science.gov (United States)

    Chiou, Kevin; Rocks, Jason; Prosser, Benjamin; Discher, Dennis; Liu, Andrea

    The heart is an active material which relies on robust signaling mechanisms between cells in order to produce well-timed, coordinated beats. Heart tissue is composed primarily of active heart muscle cells (cardiomyocytes) embedded in a passive extracellular matrix. During a heartbeat, cardiomyocyte contractions are coordinated across the heart to form a wavefront that propagates through the tissue to pump blood. In the adult heart, this contractile wave is coordinated via intercellular electrical signaling.Here we present theoretical and experimental evidence for mechanical coordination of embryonic heartbeats. We model cardiomyocytes as mechanically excitable Eshelby inclusions embedded in an overdamped elastic-fluid biphasic medium. For physiological parameters, this model replicates recent experimental measurements of the contractile wavefront which are not captured by electrical signaling models. We additionally challenge our model by pharmacologically blocking gap junctions, inhibiting electrical signaling between myocytes. We find that while adult hearts stop beating almost immediately after gap junctions are blocked, embryonic hearts continue beating even at significantly higher concentrations, providing strong support for a mechanical signaling mechanism.

  12. Unsteady fluid dynamics of several mechanical prosthetic heart valves using a two component laser Doppler anemometer system.

    Science.gov (United States)

    Akutsu, T; Modi, V J

    1997-10-01

    Five typical mechanical heart valves (Starr-Edwards, Björk-Shiley convexo-concave (c-c), Björk-Shiley monostrut, Bicer-Val, and St. Jude Medical) were tested in the mitral position under the pulsatile flow condition. The test program included measurements of velocity and turbulent stresses at 5 downstream locations. The study was carried out using a sophisticated cardiac simulator in conjunction with a highly sensitive 2 component laser Doppler anemometer (LDA) system. The continuous monitoring of parametric time histories revealed useful details about the complex flow and helped to establish the locations and times of the peak parameter values. Based upon the nondimensional presentation of data, the following general conclusions can be made. First, all the 5 valve designs created elevated turbulent stresses during the accelerating and peak flow phases, presenting the possibility of thromboembolism and perhaps hemolysis. Second, the difference in valve configuration seemed to affect the flow characteristics; third, the bileaflet design of the St. Jude valve appeared to create a lower turbulence stress level.

  13. Mechanical circulatory devices in acute heart failure.

    Science.gov (United States)

    Teuteberg, Jeffrey J; Chou, Josephine C

    2014-07-01

    Cardiogenic shock remains a leading cause of mortality despite advances in the treatment of myocardial infarction and advanced heart failure. Medical therapy can be inadequate, and patients may need mechanical circulatory support (MCS). The proper application of MCS requires knowledge of the underlying cause of acute heart failure, familiarity with the circulatory support devices, and the potential benefits and limitations of device therapy. This article describes the most commonly used temporary ventricular assist devices and their use in the various causes of cardiogenic shock.

  14. Cellular Mechanisms of Drosophila Heart Morphogenesis

    Directory of Open Access Journals (Sweden)

    Georg Vogler

    2015-02-01

    Full Text Available Many of the major discoveries in the fields of genetics and developmental biology have been made using the fruit fly, Drosophila melanogaster. With regard to heart development, the conserved network of core cardiac transcription factors that underlies cardiogenesis has been studied in great detail in the fly, and the importance of several signaling pathways that regulate heart morphogenesis, such as Slit/Robo, was first shown in the fly model. Recent technological advances have led to a large increase in the genomic data available from patients with congenital heart disease (CHD. This has highlighted a number of candidate genes and gene networks that are potentially involved in CHD. To validate genes and genetic interactions among candidate CHD-causing alleles and to better understand heart formation in general are major tasks. The specific limitations of the various cardiac model systems currently employed (mammalian and fish models provide a niche for the fly model, despite its evolutionary distance to vertebrates and humans. Here, we review recent advances made using the Drosophila embryo that identify factors relevant for heart formation. These underline how this model organism still is invaluable for a better understanding of CHD.

  15. Micro particle image velocimetry measurements of steady diastolic leakage flow in the hinge of a St. Jude Medical® regent™ mechanical heart valve.

    Science.gov (United States)

    Jun, Brian H; Saikrishnan, Neelakantan; Yoganathan, Ajit P

    2014-03-01

    A number of clinical, in vitro and computational studies have shown the potential for thromboembolic complications in bileaflet mechanical heart valves (BMHV), primarily due to the complex and unsteady flows in the valve hinges. These studies have focused on quantitative and qualitative parameters such as velocity magnitude, turbulent shear stresses, vortex formation, and platelet activation to identify potential for blood damage. However, experimental characterization of the whole flow fields within the valve hinges has not yet been conducted. This information can be utilized to investigate instantaneous damage to blood elements and also to validate numerical studies focusing on the hinge's complex fluid dynamics. The objective of this study was therefore to develop a high-resolution imaging system to characterize the flow fields and global velocity maps in a BMHV hinge. In this study, the steady leakage hinge flow fields representing the diastolic phase during the cardiac cycle in a 23 mm St. Jude Medical regent BMHV in the aortic position were characterized using a two-dimensional micro particle image velocimetry system. Diastolic flow was simulated by imposing a static pressure head on the aortic side. Under these conditions, a reverse flow jet from the aortic to the ventricular side was observed with velocities in the range of 1.47-3.24 m/s, whereas low flow regions were observed on the ventricular side of the hinge with viscous shear stress magnitude up to 60 N/m². High velocities and viscous shearing may be associated with platelet activation and hemolysis, while low flow zones can cause thrombosis due to increased residence time in the hinge. Overall, this study provides a high spatial resolution experimental technique to map the fluid velocity in the BMHV hinge, which can be extended to investigate micron-scale flow domains in various prosthetic devices under different hemodynamic conditions.

  16. Mechanical stimulation in the engineering of heart muscle.

    Science.gov (United States)

    Liaw, Norman Yu; Zimmermann, Wolfram-Hubertus

    2016-01-15

    Recreating the beating heart in the laboratory continues to be a formidable bioengineering challenge. The fundamental feature of the heart is its pumping action, requiring considerable mechanical forces to compress a blood filled chamber with a defined in- and outlet. Ventricular output crucially depends on venous loading of the ventricles (preload) and on the force generated by the preloaded ventricles to overcome arterial blood pressure (afterload). The rate of contraction is controlled by the spontaneously active sinus node and transmission of its electrical impulses into the ventricles. The underlying principles for these physiological processes are described by the Frank-Starling mechanism and Bowditch phenomenon. It is essential to consider these principles in the design and evaluation of tissue engineered myocardium. This review focuses on current strategies to evoke mechanical loading in hydrogel-based heart muscle engineering.

  17. World’s First Mechanical Heart Implanted

    Institute of Scientific and Technical Information of China (English)

    Dug; Begley; 薛文浩

    2001-01-01

    7月初,美国传来消息,第一颗人造心脏被植入人体。作为医生,职业敏感让我追逐此消息。虽然此次试验遇到了一定挫折(编者注:在我们发稿的7月19日,从媒体得到的消息,接受人造心脏的病人情况良好),但是,这是人类在使用心脏代用品的试验方面迈出了坚实的一步。本文让我想起了近20年之前的一次人工心脏的试验: In 1982, Dr. Barney Clark, 61, of Salt Lake City, Utah, survived 112 days with the first artificial heart, known as the Jarvik-7. He was confined to his bed, attached to protruding cables, tubes and the artificial heart’s noisy air compressor(空气压缩机)。 20年过去,人类在心脏外科手术方面的进展惊人!令人浮想:再过20年呢? Abiomed公司因研制了人造心脏,其股票大涨,这是题外的花边新闻。】

  18. [History, present and future of biomaterials used for artificial heart valves].

    Science.gov (United States)

    Kostrzewa, Benita; Rybak, Zbigniew

    2013-01-01

    Artificial heart valves can be classified into mechanical and biological. We have three types of mechanical heart valves: caged ball, tilting disc and bileaflet. Mechanical heart valves are made from various materials. They may be produced from metals, ceramics and polymers, e.g.: stainless steel, titanium, silicone, pyrolytic carbon. Biological valves are made from synthetic components (e.g.: PTFE, Dacron) and materials of biological origin (e.g.: cow pericardium, pig heart valve). We have also identified transcatheter aortic valve implantation (TAVI). TAVI may be produced from metals, ceramics and polymers (e.g.: stainless steel, titanium, Dacron) and biological material (e.g.: pig heart valve). This paper describes advantages and disadvantages of different types of artificial heart valves. The lifespan of mechanical valves is 20-30 years and they can be used for patients of any age. Mechanical valves have also disadvantages--anticoagulants are required to prevent thrombosis. Biological valves are made from natural materials, so they do not require prolonged anticoagulation. Their lifetime is 10-15 years, so they are offered to patients over 40 years. Another problem is the occurrence of calcification.

  19. MECHANICAL HEART-VALVE PROSTHESES - SOUND LEVEL AND RELATED COMPLAINTS

    NARCIS (Netherlands)

    LAURENS, RRP; WIT, HP; EBELS, T

    1992-01-01

    In a randomised study, we investigated the sound production of mechanical heart valve prostheses and the complaints related to this sound. The CarboMedics, Bjork-Shiley monostrut and StJude Medical prostheses were compared. A-weighted levels of the pulse-like sound produced by the prosthesis were me

  20. Structural remodeling and mechanical function in heart failure.

    Science.gov (United States)

    Leonard, Bridget Louise; Smaill, Bruce Henry; LeGrice, Ian John

    2012-02-01

    The cardiac extracellular matrix (ECM) is the three-dimensional scaffold that defines the geometry and muscular architecture of the cardiac chambers and transmits forces produced during the cardiac cycle throughout the heart wall. The cardiac ECM is an active system that responds to the stresses to which it is exposed and in the normal heart is adapted to facilitate efficient mechanical function. There are marked differences in the short- and medium-term changes in ventricular geometry and cardiac ECM that occur as a result of volume overload, hypertension, and ischemic cardiomyopathy. Despite this, there is a widespread view that a common remodeling "phenotype" governs the final progression to end-stage heart failure in different forms of heart disease. In this review article, we make the case that this interpretation is not consistent with the clinical and experimental data on the topic. We argue that there is a need for new theoretical and experimental models that will enable stresses acting on the ECM and resultant deformations to be estimated more accurately and provide better spatial resolution of local signaling mechanisms that are activated as a result. These developments are necessary to link the effects of structural remodeling with altered cardiac mechanical function.

  1. Fluid Mechanics of Heart Valves and Their Replacements

    Science.gov (United States)

    Sotiropoulos, Fotis; Le, Trung Bao; Gilmanov, Anvar

    2016-01-01

    As the pulsatile cardiac blood flow drives the heart valve leaflets to open and close, the flow in the vicinity of the valve resembles a pulsed jet through a nonaxisymmetric orifice with a dynamically changing area. As a result, three-dimensional vortex rings with intricate topology emerge that interact with the complex cardiac anatomy and give rise to shear layers, regions of recirculation, and flow instabilities that could ultimately lead to transition to turbulence. Such complex flow patterns, which are inherently valve- and patient-specific, lead to mechanical forces at scales that can cause blood cell damage and thrombosis, increasing the likelihood of stroke, and can trigger the pathogenesis of various life-threatening valvular heart diseases. We summarize the current understanding of flow phenomena induced by heart valves, discuss their linkage with disease pathways, and emphasize the research advances required to translate in-depth understanding of valvular hemodynamics into effective patient therapies.

  2. Ischemic preconditioning in immature hearts: mechanism and compatibility with cardioplegia

    Institute of Scientific and Technical Information of China (English)

    朱斌; 闵苏; 龙村; 叶铁虎

    2003-01-01

    Objective To investigate (1) whether ischemic preconditioning (IPC) could protect immature rabbit hearts against ischemia-reperfusion injury and (2) the role of KATP channel in the mechanism of myocardial protection. Since cardioplegia is a t raditional and effective cardioprotective measure in clinic, our study is also d esigned to probe the compatibility between IPC and cardioplegia.Results The recovery of CF, HR, LVDP and ±dp/dtmax in preconditioned hearts was b est am ong the four groups. The incidence of arrhythmia was low and less CK-MB leaked out in the IPC group. Myocardial ATP content was better preserved by IPC. Pre treatment with glibenclamide completely abolished the myocardial protection prov ided by IPC, but did not affect ischemia-reperfusion injury.Conclusions While applying cardioplegia, IPC provides significant cardioprotective effects. Activation of KATP channels is involved in the mechanism of IPC-produced cardioprotection.

  3. Mechanisms of high heart rate variability: a fresh look

    Directory of Open Access Journals (Sweden)

    Vladimir A. Lukyanchenko

    2016-05-01

    Full Text Available Consideration is being given herein to some mechanisms of high heart rate variability (high HRV, which cannot be attributed to sports exercise loading. The mechanism responsible for high HRV is explained as that resulted from the continuous performance (opening and closure of arteriovenous anastomoses in different organs and systems in a human organism. An assessment of this phenomenon is given herein from the point of view of a practicing physician who treats regularly patients with already established clinical diagnoses and those without an established nosological profile according to International Statistical Classification of Diseases and Related Health Problems 10th Revision.

  4. Cardiac crossroads: deciding between mechanical or bioprosthetic heart valve replacement

    Directory of Open Access Journals (Sweden)

    Maggie N Tillquist

    2011-02-01

    Full Text Available Maggie N Tillquist1, Thomas M Maddox21School of Medicine, University of Colorado Denver, Denver, CO, USA; 2VA Eastern Colorado Health Care System, and Department of Medicine (Cardiology, University of Colorado Denver, Denver, CO, USAAbstract: Nearly 15 million people in the United States suffer from either aortic or mitral valvular disease. For patients with severe and symptomatic valvular heart disease, valve replacement surgery improves morbidity and mortality outcomes. In 2009, 90,000 valve replacement surgeries were performed in the United States. This review evaluates the advantages and disadvantages of mechanical and bioprosthetic prosthetic heart valves as well as the factors for consideration in deciding the appropriate valve type for an individual patient. Although many caveats exist, the general recommendation is for patients younger than 60 to 65 years to receive mechanical valves due to the valve's longer durability and for patients older than 60 to 65 years to receive a bioprosthetic valve to avoid complications with anticoagulants. Situations that warrant special consideration include patient co-morbidities, the need for anticoagulation, and the potential for pregnancy. Once these characteristics have been considered, patients' values, anxieties, and expectations for their lifestyle and quality of life should be incorporated into final valve selection. Decision aids can be useful in integrating preferences in the valve decision. Finally, future directions in valve technology, anticoagulation, and medical decision-making are discussed.Keywords: prosthetic heart valves, patient preference, valve type, anticoagulant, structural valve deterioration 

  5. Introducing a novel mechanism to control heart rate in the ancestral Pacific hagfish.

    Science.gov (United States)

    Wilson, Christopher M; Roa, Jinae N; Cox, Georgina K; Tresguerres, Martin; Farrell, Anthony P

    2016-10-15

    Although neural modulation of heart rate is well established among chordate animals, the Pacific hagfish (Eptatretus stoutii) lacks any cardiac innervation, yet it can increase its heart rate from the steady, depressed heart rate seen in prolonged anoxia to almost double its normal normoxic heart rate, an almost fourfold overall change during the 1-h recovery from anoxia. The present study sought mechanistic explanations for these regulatory changes in heart rate. We provide evidence for a bicarbonate-activated, soluble adenylyl cyclase (sAC)-dependent mechanism to control heart rate, a mechanism never previously implicated in chordate cardiac control.

  6. Effect of Induced Vibration on the Blood Flow Properties in a Mechanical Aortic Valve

    Directory of Open Access Journals (Sweden)

    Kadhim Saleem Khalefa

    2014-07-01

    Full Text Available The effect of induced vibration on velocity distribution for the blood flow in the bileaflet mechanical heart valves conveying blood was investigated in this study. The bileaflet valve was simulated as an orifice. The induced vibration is due to the pulsed blood flow in the artery. Results presented in this study were performed using CFD FLUENT software. This analysis is based on the non-linear numerical solution by using a finite-element method, for the system of governing partial differential equations (continuity, momentum of Navier - Stokes equation of blood flow through the orifice. It has been found that as the flow through the orifice increased, the vibration at the orifice inlet increased. For steady state conditions, at Reynolds number 50 the recorded frequency was 20Hz. When the Reynolds number increased to 100 due to the increase in the blood flow the recorded frequency increased to 30Hz. The increase in frequency may result in damaging the blood red cells and platelets which subsequently results in increasing the blood clogging downstream of the orifice.

  7. Ethanol exposure alters early cardiac function in the looping heart: a mechanism for congenital heart defects?

    Science.gov (United States)

    Karunamuni, Ganga; Gu, Shi; Doughman, Yong Qiu; Peterson, Lindsy M; Mai, Katherine; McHale, Quinn; Jenkins, Michael W; Linask, Kersti K; Rollins, Andrew M; Watanabe, Michiko

    2014-02-01

    Alcohol-induced congenital heart defects are frequently among the most life threatening and require surgical correction in newborns. The etiology of these defects, collectively known as fetal alcohol syndrome, has been the focus of much study, particularly involving cellular and molecular mechanisms. Few studies have addressed the influential role of altered cardiac function in early embryogenesis because of a lack of tools with the capability to assay tiny beating hearts. To overcome this gap in our understanding, we used optical coherence tomography (OCT), a nondestructive imaging modality capable of micrometer-scale resolution imaging, to rapidly and accurately map cardiovascular structure and hemodynamics in real time under physiological conditions. In this study, we exposed avian embryos to a single dose of alcohol/ethanol at gastrulation when the embryo is sensitive to the induction of birth defects. Late-stage hearts were analyzed using standard histological analysis with a focus on the atrio-ventricular valves. Early cardiac function was assayed using Doppler OCT, and structural analysis of the cardiac cushions was performed using OCT imaging. Our results indicated that ethanol-exposed embryos developed late-stage valvuloseptal defects. At early stages, they exhibited increased regurgitant flow and developed smaller atrio-ventricular cardiac cushions, compared with controls (uninjected and saline-injected embryos). The embryos also exhibited abnormal flexion/torsion of the body. Our evidence suggests that ethanol-induced alterations in early cardiac function have the potential to contribute to late-stage valve and septal defects, thus demonstrating that functional parameters may serve as early and sensitive gauges of cardiac normalcy and abnormalities.

  8. Radiation-Induced Heart Disease: Pathologic Abnormalities and Putative Mechanisms

    Directory of Open Access Journals (Sweden)

    Neil K Taunk

    2015-02-01

    Full Text Available Breast cancer is a common diagnosis in women. Breast radiation has become a critical in managing patients who receive breast conserving surgery, or have certain high-risk features after mastectomy. Most patients have an excellent prognosis, therefore understanding the late effects of radiation to the chest is important. Radiation induced heart disease (RIHD comprises a spectrum of cardiac pathology including myocardial fibrosis and cardiomyopathy, coronary artery disease, valvular disease, pericardial disease, and arrhythmias. Tissue fibrosis is a common mediator in RIHD. Multiple pathways converge with both acute and chronic cellular, molecular, and genetic changes to result in fibrosis. In this article, we review the pathophysiology of cardiac disease related to radiation therapy to the chest. Our understanding of these mechanisms has improved substantially, but much work remains to further refine radiation delivery techniques and develop therapeutics to battle late effects of radiation.

  9. Mechanical analysis of congestive heart failure caused by bundle branch block based on an electromechanical canine heart model

    Science.gov (United States)

    Dou, Jianhong; Xia, Ling; Zhang, Yu; Shou, Guofa; Wei, Qing; Liu, Feng; Crozier, Stuart

    2009-01-01

    Asynchronous electrical activation, induced by bundle branch block (BBB), can cause reduced ventricular function. However, the effects of BBB on the mechanical function of heart are difficult to assess experimentally. Many heart models have been developed to investigate cardiac properties during BBB but have mainly focused on the electrophysiological properties. To date, the mechanical function of BBB has not been well investigated. Based on a three-dimensional electromechanical canine heart model, the mechanical properties of complete left and right bundle branch block (LBBB and RBBB) were simulated. The anatomical model as well as the fiber orientations of a dog heart was reconstructed from magnetic resonance imaging (MRI) and diffusion tensor MRI (DT-MRI). Using the solutions of reaction-diffusion equations and with a strategy of parallel computation, the asynchronous excitation propagation and intraventricular conduction in BBB was simulated. The mechanics of myocardial tissues were computed with time-, sarcomere length-dependent uniaxial active stress initiated at the time of depolarization. The quantification of mechanical intra- and interventricular asynchrony of BBB was then investigated using the finite-element method with an eight-node isoparametric element. The simulation results show that (1) there exists inter- and intraventricular systolic dyssynchrony during BBB; (2) RBBB may have more mechanical synchrony and better systolic function of the left ventricle (LV) than LBBB; (3) the ventricles always move toward the early-activated ventricle; and (4) the septum experiences higher stress than left and right ventricular free walls in BBB. The simulation results validate clinical and experimental recordings of heart deformation and provide regional quantitative estimates of ventricular wall strain and stress. The present work suggests that an electromechanical heart model, incorporating real geometry and fiber orientations, may be helpful for better

  10. Mechanical analysis of congestive heart failure caused by bundle branch block based on an electromechanical canine heart model

    Energy Technology Data Exchange (ETDEWEB)

    Dou Jianhong; Xia Ling; Zhang Yu; Shou Guofa [Department of Biomedical Engineering, Zhejiang University, Hangzhou 310027 (China); Wei Qing; Liu Feng; Crozier, Stuart [School of Information Technology and Electrical Engineering, University of Queensland, St Lucia, Brisbane, Queensland 4072 (Australia)], E-mail: xialing@zju.edu.cn

    2009-01-21

    Asynchronous electrical activation, induced by bundle branch block (BBB), can cause reduced ventricular function. However, the effects of BBB on the mechanical function of heart are difficult to assess experimentally. Many heart models have been developed to investigate cardiac properties during BBB but have mainly focused on the electrophysiological properties. To date, the mechanical function of BBB has not been well investigated. Based on a three-dimensional electromechanical canine heart model, the mechanical properties of complete left and right bundle branch block (LBBB and RBBB) were simulated. The anatomical model as well as the fiber orientations of a dog heart was reconstructed from magnetic resonance imaging (MRI) and diffusion tensor MRI (DT-MRI). Using the solutions of reaction-diffusion equations and with a strategy of parallel computation, the asynchronous excitation propagation and intraventricular conduction in BBB was simulated. The mechanics of myocardial tissues were computed with time-, sarcomere length-dependent uniaxial active stress initiated at the time of depolarization. The quantification of mechanical intra- and interventricular asynchrony of BBB was then investigated using the finite-element method with an eight-node isoparametric element. The simulation results show that (1) there exists inter- and intraventricular systolic dyssynchrony during BBB; (2) RBBB may have more mechanical synchrony and better systolic function of the left ventricle (LV) than LBBB; (3) the ventricles always move toward the early-activated ventricle; and (4) the septum experiences higher stress than left and right ventricular free walls in BBB. The simulation results validate clinical and experimental recordings of heart deformation and provide regional quantitative estimates of ventricular wall strain and stress. The present work suggests that an electromechanical heart model, incorporating real geometry and fiber orientations, may be helpful for better

  11. The mechanisms of muscle wasting in COPD and heart failure

    Directory of Open Access Journals (Sweden)

    Giorgio Vescovo

    2012-10-01

    Full Text Available Many of the mechanisms leading to skeletal muscle wasting in COPD and heart failure are common to both conditions. These encompass neurohormonal activation and systemic inflammation. The mechanisms leading to muscle dysfunction are both qualitative and quantitative. Qualitative changes comprise the transition from aerobic metabolism and prevalent slow fibers composition toward anaerobic metabolism and fast fibers synthesis. Quantitative changes are mainly linked to muscle loss. These changes occur not only in the major muscles bulks of the body but also in respiratory muscles. The mechanisms leading to muscle wastage include cytokine-triggered skeletal muscle apoptosis and ubiquitin-proteasomeand non-ubiquitin-dependent pathways. The regulation of fiber type involves the growth hormone/insulin-like growth factor 1/calcineurin/transcriptional coactivator PGC1 cascade. The imbalance between protein synthesis and degradation plays an important role. Protein degradation can occur through ubiquitin-dependent and non-ubiquitin-dependent pathways. Very recently, two systems controlling ubiquitin-proteasome activation have been described: FOXO-ubiquitin ligase and NFkB ubiquitin ligase. These are triggered by TNFα and growth hormone/insulin-like growth factor 1. Moreover, apoptosis, which is triggered by tumor necrosis factor α, plays an important role. Another mechanism acting on muscle wastage is malnutrition, with an imbalance between catabolic and anabolic factors toward the catabolic component. Catabolism is also worsened by the activation of the adrenergic system and alteration of the cortisol/DEHA ratio toward cortisol production. Sarcomeric protein oxidation and its consequent contractile impairment can be another cause of skeletal muscle dysfunction in CHF.

  12. A Nodal-independent and tissue-intrinsic mechanism controls heart-looping chirality

    Science.gov (United States)

    Noël, Emily S.; Verhoeven, Manon; Lagendijk, Anne Karine; Tessadori, Federico; Smith, Kelly; Choorapoikayil, Suma; den Hertog, Jeroen; Bakkers, Jeroen

    2013-11-01

    Breaking left-right symmetry in bilateria is a major event during embryo development that is required for asymmetric organ position, directional organ looping and lateralized organ function in the adult. Asymmetric expression of Nodal-related genes is hypothesized to be the driving force behind regulation of organ laterality. Here we identify a Nodal-independent mechanism that drives asymmetric heart looping in zebrafish embryos. In a unique mutant defective for the Nodal-related southpaw gene, preferential dextral looping in the heart is maintained, whereas gut and brain asymmetries are randomized. As genetic and pharmacological inhibition of Nodal signalling does not abolish heart asymmetry, a yet undiscovered mechanism controls heart chirality. This mechanism is tissue intrinsic, as explanted hearts maintain ex vivo retain chiral looping behaviour and require actin polymerization and myosin II activity. We find that Nodal signalling regulates actin gene expression, supporting a model in which Nodal signalling amplifies this tissue-intrinsic mechanism of heart looping.

  13. Reconstitution of the Frank-Starling Mechanism in Engineered Heart Tissues

    OpenAIRE

    Asnes, Clara F.; Marquez, J. Pablo; Elson, Elliot L.; Wakatsuki, Tetsuro

    2006-01-01

    According to the Frank-Starling mechanism, as the heart is stretched, it increases its contraction force. Reconstitution of the Frank-Starling mechanism is an important milestone for producing functional heart tissue constructs. Spontaneously contracting engineered heart tissues (EHTs) were reconstituted by growing dissociated chicken embryo cardiomyocytes in collagen matrices. Twitch and baseline tensions were recorded at precisely controlled levels of tissue strain. The EHTs showed a steep ...

  14. Central Mechanisms of Abnormal Sympathoexcitation in Chronic Heart Failure

    Directory of Open Access Journals (Sweden)

    Takuya Kishi

    2012-01-01

    Full Text Available It has been recognized that the sympathetic nervous system is abnormally activated in chronic heart failure, and leads to further worsening chronic heart failure. In the treatment of chronic heart failure many clinical studies have already suggested that the inhibition of the abnormal sympathetic hyperactivity by beta blockers is beneficial. It has been classically considered that abnormal sympathetic hyperactivity in chronic heart failure is caused by the enhancement of excitatory inputs including changes in peripheral baroreceptor and chemoreceptor reflexes and chemical mediators that control sympathetic outflow. Recently, the abnormalities in the central regulation of sympathetic nerve activity mediated by brain renin angiotensin system-oxidative stress axis and/or proinflammatory cytokines have been focused. Central renin angiotensin system, proinflammatory cytokines, and the interaction between them have been determined as the target of the sympathoinhibitory treatment in experimental animal models with chronic heart failure. In conclusion, we must recognize that chronic heart failure is a syndrome with an abnormal sympathoexcitation, which is caused by the abnormalities in the central regulation of sympathetic nerve activity.

  15. [Present status and trend of heart fluid mechanics research based on medical image analysis].

    Science.gov (United States)

    Gan, Jianhong; Yin, Lixue; Xie, Shenghua; Li, Wenhua; Lu, Jing; Luo, Anguo

    2014-06-01

    With introduction of current main methods for heart fluid mechanics researches, we studied the characteristics and weakness for three primary analysis methods based on magnetic resonance imaging, color Doppler ultrasound and grayscale ultrasound image, respectively. It is pointed out that particle image velocity (PIV), speckle tracking and block match have the same nature, and three algorithms all adopt block correlation. The further analysis shows that, with the development of information technology and sensor, the research for cardiac function and fluid mechanics will focus on energy transfer process of heart fluid, characteristics of Chamber wall related to blood fluid and Fluid-structure interaction in the future heart fluid mechanics fields.

  16. Mechanism of relation among heart meridian, referred cardiac pain and heart

    Institute of Scientific and Technical Information of China (English)

    RONG; Peijing(荣培晶); ZHU; Bing(朱兵)

    2002-01-01

    It has been demonstrated that an important clinical phenomenon often associated with visceral diseases is the referred pain to somatic structures, especially to the body areaof homo-segmental innervation. It is interesting that the somatic foci of cardiac referred pain wereoften and mainly distributed along the heart meridian (HM), whereas the acupoints of HM havebeen applied to treat cardiac disease since ancient times. The purpose of this study was to inves-tigate the neural relationship between the cardiac referred pain and the heart meridian.Fluorescent triple-labeling was injected into the pericardium, some acupoints of HM and lung me-ridian (LM, for control). The responses of the left cardiac sympathetic nerve and of the EMG in left HM and LM were electrophysiologically studied, when the electrical stimuli were applied to the acupoints of left HM and to the left cardiac sympathetic nerve. More double-labeled neurons in HM-heart, not in LM-heart, were observed in the ipsilateral dorsal root ganglia of the spinal segments C8-T3. Electric stimulation of the acupoints of left HM was able to elicit more responses of left cardiac sympathetic nerve than that of the LM-acupoints. Electric stimulation of the left cardiac sympathetic nerve resulted in stronger activities of EMG-response in the acupoints of left HM than in LM-acupoints. We conclude that double-labeling study has provided direct evidence for the existence of dichotomizing afferent fibers that supply both the pericardium and HM. Electrophysiological results show that HM is more closely related functionally to heart. These findings provide a possible morphological and physiological explanation for the referred cardiac pain and HM-heart interrelation.

  17. Fractal mechanisms in the electrophysiology of the heart

    Science.gov (United States)

    Goldberger, A. L.

    1992-01-01

    The mathematical concept of fractals provides insights into complex anatomic branching structures that lack a characteristic (single) length scale, and certain complex physiologic processes, such as heart rate regulation, that lack a single time scale. Heart rate control is perturbed by alterations in neuro-autonomic function in a number of important clinical syndromes, including sudden cardiac death, congestive failure, cocaine intoxication, fetal distress, space sickness and physiologic aging. These conditions are associated with a loss of the normal fractal complexity of interbeat interval dynamics. Such changes, which may not be detectable using conventional statistics, can be quantified using new methods derived from "chaos theory.".

  18. Mechanical ventilation-induced intrathoracic pressure distribution and heart-lung interactions*

    NARCIS (Netherlands)

    Lansdorp, B.; Hofhuizen, C.M.; Lavieren, M. van; Swieten, H.A. van; Lemson, J.; Putten, M.J.A.M. van; Hoeven, J.G. van der; Pickkers, P.

    2014-01-01

    OBJECTIVE: Mechanical ventilation causes cyclic changes in the heart's preload and afterload, thereby influencing the circulation. However, our understanding of the exact physiology of this cardiopulmonary interaction is limited. We aimed to thoroughly determine airway pressure distribution, how thi

  19. Is thrombosis a contributor to heart failure pathophysiology? Possible mechanisms, therapeutic opportunities, and clinical investigation challenges

    NARCIS (Netherlands)

    Zannad, F.; Stough, W.G.; Regnault, V.; Gheorghiade, M.; Deliargyris, E.; Gibson, C.M.; Agewall, S.; Berkowitz, S.D.; Burton, P.; Calvo, G.; Goldstein, S.; Verheugt, F.W.A.; Koglin, J.; O'Connor, C.M.

    2013-01-01

    Thrombotic events (coronary thrombosis, venous thromboembolism, intraventricular thrombosis, intracranial and systemic thromboembolism) occur frequently in patients with heart failure. These events may be precipitated by several mechanisms including hypercoagulability through enhancement of procoagu

  20. Thromboembolism and mechanical heart valves : A randomized study revisited

    NARCIS (Netherlands)

    Kuntze, CEE; Blackstone, EH; Ebels, T

    1998-01-01

    Background. This study was designed to revise and substantiate previous inferences, based on short-term follow-up, about differences in the incidence of anticoagulant-related events after heart valve replacement among patients who had been randomly assigned to receive either a Bjork-Shiley, Edwards-

  1. Exercise training in chronic heart failure: mechanisms and therapies

    OpenAIRE

    Piepoli, M. F.

    2012-01-01

    Decreased exercise capacity negatively affects the individuals’ ability to adequately perform activities required for normal daily life and, therefore, the independence and quality of life. Regular exercise training is associated with improved quality of life and survival in healthy individuals and in cardiovascular disease patients. Also in patients with stable heart failure, exercise training can relieve symptoms, improve exercise capacity and reduce disability, hospitalisation and probably...

  2. Influence of metabolic dysfunction on cardiac mechanics in decompensated hypertrophy and heart failure.

    Science.gov (United States)

    Tewari, Shivendra G; Bugenhagen, Scott M; Vinnakota, Kalyan C; Rice, J Jeremy; Janssen, Paul M L; Beard, Daniel A

    2016-05-01

    Alterations in energetic state of the myocardium are associated with decompensated heart failure in humans and in animal models. However, the functional consequences of the observed changes in energetic state on mechanical function are not known. The primary aim of the study was to quantify mechanical/energetic coupling in the heart and to determine if energetic dysfunction can contribute to mechanical failure. A secondary aim was to apply a quantitative systems pharmacology analysis to investigate the effects of drugs that target cross-bridge cycling kinetics in heart failure-associated energetic dysfunction. Herein, a model of metabolite- and calcium-dependent myocardial mechanics was developed from calcium concentration and tension time courses in rat cardiac muscle obtained at different lengths and stimulation frequencies. The muscle dynamics model accounting for the effect of metabolites was integrated into a model of the cardiac ventricles to simulate pressure-volume dynamics in the heart. This cardiac model was integrated into a simple model of the circulation to investigate the effects of metabolic state on whole-body function. Simulations predict that reductions in metabolite pools observed in canine models of heart failure can cause systolic dysfunction, blood volume expansion, venous congestion, and ventricular dilation. Simulations also predict that myosin-activating drugs may partially counteract the effects of energetic state on cross-bridge mechanics in heart failure while increasing myocardial oxygen consumption. Our model analysis demonstrates how metabolic changes observed in heart failure are alone sufficient to cause systolic dysfunction and whole-body heart failure symptoms.

  3. Valve-related complications after mechanical heart valve implantation.

    Science.gov (United States)

    Misawa, Yoshio

    2015-10-01

    The number of heart valve surgeries is increasing, and 19,164 patients underwent heart valve surgery in Japan in 2011. The early mortality rate has remained stable for more than 10 years. Many patients now survive for many years, with a reported 10-year survival rate of at least 60 %. However, unfavorable complications can occur after valve surgery. Valve-related complications include thromboembolisms, bleeding complications and prosthetic valve endocarditis, followed by structural and nonstructural prosthetic valve dysfunctions. Our review of studies published after 2000 revealed that the rate of all valve-related complications was 0.7-3.5 % per patient-year. Thromboembolisms occur at a rate of approximately 1 % per patient-year, and bleeding complications occur at almost 0.5 % per patient-year. Thromboembolic and hemorrhagic events related to anticoagulant therapy should be considered during life-long follow-up. The occurrence rate of endocarditis reaches 0.5 % per patient-year, with a poor postoperative survival. Structural dysfunctions have been largely overcome, and the nonstructural dysfunction rate is 0.4-1.2 % per patient-year. The nonstructural dysfunctions induced by paravalvular leaks and pannus ingrowth are also issues that need to be resolved.

  4. The contribution of inspiratory muscles function to exercise limitation in heart failure: pathophysiological mechanisms

    OpenAIRE

    Jorge P. Ribeiro; Chiappa, Gaspar R.; Carine C. Callegaro

    2012-01-01

    BACKGROUND: Heart failure induces histological, metabolic and functional adaptations in the inspiratory muscles. This inspiratory muscle weakness, which occurs in 30% to 50% of the heart failure patients, is associated with reduction in the functional capacity, reduction in the quality of life and with a poor prognosis in these individuals. OBJECTIVES: The objective of this review was to discuss the pathophysiological mechanisms that may explain the role of the inspiratory muscles in the exer...

  5. Computer-assisted design of butterfly bileaflet valves for the mitral position.

    Science.gov (United States)

    McQueen, D M; Peskin, C S

    1985-01-01

    This paper describes the application of computer testing to a design study of butterfly bileaflet mitral prostheses having flat or curved leaflets. The curvature is in the plane normal to the pivot axes and is such that the convex sides of the leaflets face each other when the valve is open. The design parameters considered are the curvature of the leaflets and the location of the pivot points. In this study, stagnation is assessed by computing the smallest value (over the three openings of the valve) of the peak velocity, and hemodynamic performance is judged by a benefit/cost ratio: the net stroke volume divided by the mean transvalvular pressure difference. Unlike the case of a pivoting single-disc valve, the inclusion of a constraint on the maximum angle of opening of the leaflets is found to be essential for adequate, competent performance. Results are presented with both 85 degrees and 90 degrees constraints, since best performance is achieved with the opening-angle constraint in this range. Asymmetry of leaflet motion which is observed with flat leaflets in the mitral position is reduced with modest leaflet curvature. Leaflet curvature also ameliorates central orifice stagnation, which is observed with flat leaflets. Curvature of the valve produces the following improvements in comparison with the best flat valve when the opening-angle constraint is 85 degrees: a 38% increase in the minimum peak velocity and a 16% increase in the hemodynamic benefit/cost ratio. With a 90 degrees constraint the corresponding improvements are 34% and 20%, respectively.

  6. Ex vivo stretch reveals altered mechanical properties of isolated dystrophin-deficient hearts.

    Directory of Open Access Journals (Sweden)

    Matthew S Barnabei

    Full Text Available Duchenne muscular dystrophy (DMD is a progressive and fatal disease of muscle wasting caused by loss of the cytoskeletal protein dystrophin. In the heart, DMD results in progressive cardiomyopathy and dilation of the left ventricle through mechanisms that are not fully understood. Previous reports have shown that loss of dystrophin causes sarcolemmal instability and reduced mechanical compliance of isolated cardiac myocytes. To expand upon these findings, here we have subjected the left ventricles of dystrophin-deficient mdx hearts to mechanical stretch. Unexpectedly, isolated mdx hearts showed increased left ventricular (LV compliance compared to controls during stretch as LV volume was increased above normal end diastolic volume. During LV chamber distention, sarcomere lengths increased similarly in mdx and WT hearts despite greater excursions in volume of mdx hearts. This suggests that the mechanical properties of the intact heart cannot be modeled as a simple extrapolation of findings in single cardiac myocytes. To explain these findings, a model is proposed in which disruption of the dystrophin-glycoprotein complex perturbs cell-extracellular matrix contacts and promotes the apparent slippage of myocytes past each other during LV distension. In comparison, similar increases in LV compliance were obtained in isolated hearts from β-sarcoglycan-null and laminin-α(2 mutant mice, but not in dysferlin-null mice, suggesting that increased whole-organ compliance in mdx mice is a specific effect of disrupted cell-extracellular matrix contacts and not a general consequence of cardiomyopathy via membrane defect processes. Collectively, these findings suggest a novel and cell-death independent mechanism for the progressive pathological LV dilation that occurs in DMD.

  7. ENDURANCE TRAINING AND GLUTATHIONE-DEPENDENT ANTIOXIDANT DEFENSE MECHANISM IN HEART OF THE DIABETIC RATS

    Directory of Open Access Journals (Sweden)

    Mustafa Atalay

    2003-06-01

    Full Text Available Regular physical exercise beneficially influences cardiac antioxidant defenses in normal rats. The aim of this study was to test whether endurance training can strengthen glutathione-dependent antioxidant defense mechanism and decrease lipid peroxidation in heart of the streptozotocin-induced diabetic rats. Redox status of glutathione in blood of diabetic rats in response to training and acute exercise was also examined. Eight weeks of treadmill training increased the endurance in streptozotocin-induced diabetic rats. It did not affect glutathione level in heart tissue at rest and also after exercise. On the other hand, endurance training decreased glutathione peroxidase activity in heart, while glutathione reductase and glutathione S-transferase activities were not affected either by acute exhaustive exercise or endurance training. Reduced and oxidized glutathione levels in blood were not affected by either training or acute exercise. Conjugated dienes levels in heart tissue were increased by acute exhaustive exercise and also 8 weeks treadmill training. Longer duration of exhaustion in trained group may have contributed to the increased conjugated dienes levels in heart after acute exercise. Our results suggest that endurance type exercise may make heart more susceptible to oxidative stress. Therefore it may be wise to combine aerobic exercise with insulin treatment to prevent its adverse effects on antioxidant defense in heart in patients with diabetes mellitus

  8. Self-management of oral anticoagulant therapy for mechanical heart valve patients

    DEFF Research Database (Denmark)

    Christensen, Thomas D; Attermann, Jørn; Pilegaard, Hans K;

    2001-01-01

    .4%–2.9%) for the control group. Conclusion: Self-management of OAT is a feasible and safe concept for selected patients with mechanical heart valve prostheses also on a long-term basis. It provides at least as good and most likely better quality of anticoagulant therapy than conventional management assessed by time within......Objective: Self-management of oral anticoagulant therapy (OAT) has shown good results on a short-term basis. We hypothesize that self-management of OAT provides a better quality of treatment than conventional management also on a long-term basis. The aim of this study was to assess the quality...... of self-management of OAT in patients with mechanical heart valve prostheses on a 4-year perspective in a prospective, non-randomized study. Design: Twenty-four patients with mechanical heart valves and on self-managed OAT were followed for up to 4 years. A matched, retrospectively selected group...

  9. Time-resolved PIV technique for high temporal resolution measurement of mechanical prosthetic aortic valve fluid dynamics.

    Science.gov (United States)

    Kaminsky, R; Morbiducci, U; Rossi, M; Scalise, L; Verdonck, P; Grigioni, M

    2007-02-01

    Prosthetic heart valves (PHVs) have been used to replace diseased native valves for more than five decades. Among these, mechanical PHVs are the most frequently implanted. Unfortunately, these devices still do not achieve ideal behavior and lead to many complications, many of which are related to fluid mechanics. The fluid dynamics of mechanical PHVs are particularly complex and the fine-scale characteristics of such flows call for very accurate experimental techniques. Adequate temporal resolution can be reached by applying time-resolved PIV, a high-resolution dynamic technique which is able to capture detailed chronological changes in the velocity field. The aim of this experimental study is to investigate the evolution of the flow field in a detailed time domain of a commercial bileaflet PHV in a mock-loop mimicking unsteady conditions, by means of time-resolved 2D Particle Image Velocimetry (PIV). The investigated flow field corresponded to the region immediately downstream of the valve plane. Spatial resolution as in "standard" PIV analysis of prosthetic valve fluid dynamics was used. The combination of a Nd:YLF high-repetition-rate double-cavity laser with a high frame rate CMOS camera allowed a detailed, highly temporally resolved acquisition (up to 10000 fps depending on the resolution) of the flow downstream of the PHV. Features that were observed include the non-homogeneity and unsteadiness of the phenomenon and the presence of large-scale vortices within the field, especially in the wake of the valve leaflets. Furthermore, we observed that highly temporally cycle-resolved analysis allowed the different behaviors exhibited by the bileaflet valve at closure to be captured in different acquired cardiac cycles. By accurately capturing hemodynamically relevant time scales of motion, time-resolved PIV characterization can realistically be expected to help designers in improving PHV performance and in furnishing comprehensive validation with experimental data

  10. Simulations of heart mechanics over the cardiac cycle

    Science.gov (United States)

    Tavoularis, Stavros; Doyle, Matthew; Bourgault, Yves

    2009-11-01

    This study is concerned with the numerical simulation of blood flow and myocardium motion with fluid-structure interaction of the left ventricle (LV) of a canine heart over the entire cardiac cycle. The LV geometry is modeled as a series of nested prolate ellipsoids and is capped with cylindrical tubes representing the inflow and outflow tracts. The myocardium is modeled as a multi-layered, slightly compressible, transversely isotropic, hyperelastic material, with each layer having different principal directions to approximate the fibrous structure. Blood is modeled as a slightly compressible Newtonian fluid. Blood flow into and out of the LV is driven by left atrial and aortic pressures applied at the distal ends of the inflow and outflow tracts, respectively, along with changes in the stresses in the myocardium caused by time-dependent changes in its material properties, which simulate the cyclic contraction and relaxation of the muscle fibers. Numerical solutions are obtained with the use of a finite element code. The computed temporal and spatial variations of pressure and velocity in the blood and stresses and strains in the myocardium will be discussed and compared to physiological data. The variation of the LV cavity volume over the cardiac cycle will also be discussed.

  11. Mechanism of Microbubble Growth at Mitral Mechanical Heart Valve (MHV) Closure

    Science.gov (United States)

    Rambod, Edmond; Beizaie, Masoud; Shusser, Michael; Gharib, Morteza

    1999-11-01

    The growth mechanism of microbubbles at mitral MHV closure has been experimentally studied. In the heart, some of the tiny bubbles grow explosively and form larger and persistent bubbles. An experimental set-up was designed to allow the passage of micron-size bubbles through an 80 micron-wide slot, simulating a typical gap between the housing ring and the occluders in MHV. The bubbles were generated using an air-liquid dispenser and were delivered to the system via a 250 micron-diameter hypedermic needle positioned vertically near the slot. A solenoid valve was used to deliver a 10cc volume of liquid in 25ms time through the slot. High-speed imaging was used to study the impact of flow through the slot on bubble growth. The velocity of liquid through the slot was assessed to be in the range of 12-15 m/s. Our observations confirmed the rapid and drastic growth of microbubbles following their passage through the narrow slot, due to pressure drop. Vortices, which were induced by flow separation on the downstream of the slot, caused the grown bubbles to shatter and form more stable bubbles.

  12. Stress activated contractile wavefronts in the mechanically-excitable embryonic heart

    Science.gov (United States)

    Chiou, Kevin; Majkut, Stephanie; Discher, Dennis; Lubensky, Tom; Liu, Andrea

    2014-03-01

    The heart is a prime example of a robust, active system with behavior-the heart beat-that is extraordinarily well timed and coordinated. For more than half a century, electrical activity induced by ion release and diffusion has been argued to be the mechanism driving cardiac action. But recent work indicates that this phenomenon is also regulated by mechanical activity. In the embryonic avian heart tube, the speed of the contractile wavefront traversing the heart tube with each beat is measured to be a monotonic, linear function of tissue stiffness. Traditional electrical conduction models of excitation-contraction cannot explain this dependence; such a result indicates that the myocardium is mechanically excitable. Here, we extend this work by using experimental observations of stiffness-dependent behavior in isolated cardiomyocytes as an input to study contractile wavefronts in the tissue as a whole. We model the heart tube as an active, overdamped elastic network where the primary stress mediator is the extracellular matrix. Using this simple model, we explain experimental observations of the systolic wave and predict qualitatively new behavior.

  13. A surgical robot with a heart-surface-motion synchronization mechanism for myoblast cell sheet transplantation.

    Science.gov (United States)

    Xu, Kangyi; Nakamura, Ryoichi

    2013-01-01

    Myoblast cell sheets are employed in the clinical treatment of heart disorders. We propose a surgical robot system with two endoscopic cameras, characterized by a double remote center of motion (RCM) mechanism, to realize heart-surface-motion synchronization movement for myoblast cell sheet transplantation on a beating heart surface. A robot system with the double RCM mechanism was developed for which the linear and rotation motions are totally isolated, and an experiment was conducted to evaluate the tracking accuracy of the robot system when tracking a randomly moving target. The tracking data were updated with a Polaris system at 30 Hz. The experiment results showed linear and rotation tracking errors of 4.93 ± 5.92 mm and 2.54 ± 5.44°, respectively.

  14. Education and Coronary Heart Disease Risk: Potential Mechanisms Such as Literacy, Perceived Constraints, and Depressive Symptoms

    Science.gov (United States)

    Loucks, Eric B.; Gilman, Stephen E.; Howe, Chanelle J.; Kawachi, Ichiro; Kubzansky, Laura D.; Rudd, Rima E.; Martin, Laurie T.; Nandi, Arijit; Wilhelm, Aude; Buka, Stephen L.

    2015-01-01

    Objective: Education is inversely associated with coronary heart disease (CHD) risk; however the mechanisms are poorly understood. The study objectives were to evaluate the extent to which rarely measured factors (literacy, time preference, sense of control) and more commonly measured factors (income, depressive symptomatology, body mass index) in…

  15. Titin and Troponin: Central Players in the Frank-Starling Mechanism of the Heart

    OpenAIRE

    Fukuda, Norio; Terui, Takako; Ohtsuki, Iwao; Ishiwata, Shin’ichi; Kurihara, Satoshi

    2009-01-01

    The basis of the Frank-Starling mechanism of the heart is the intrinsic ability of cardiac muscle to produce greater active force in response to stretch, a phenomenon known as length-dependent activation. A feedback mechanism transmitted from cross-bridge formation to troponin C to enhance Ca2+ binding has long been proposed to account for length-dependent activation. However, recent advances in muscle physiology research technologies have enabled the identification of other factors involved ...

  16. Mechanical Circulatory Support Devices for Pediatric Patients With Congenital Heart Disease.

    Science.gov (United States)

    Chopski, Steven G; Moskowitz, William B; Stevens, Randy M; Throckmorton, Amy L

    2017-01-01

    The use of mechanical circulatory support (MCS) devices is a viable therapeutic treatment option for patients with congestive heart failure. Ventricular assist devices, cavopulmonary assist devices, and total artificial heart pumps continue to gain acceptance as viable treatment strategies for both adults and pediatric patients as bridge-to-transplant, bridge-to-recovery, and longer-term circulatory support alternatives. We present a review of the current and future MCS devices for patients having congenital heart disease (CHD) with biventricular or univentricular circulations. Several devices that are specifically designed for patients with complex CHD are in the development pipeline undergoing rigorous animal testing as readiness experiments in preparation for future clinical trials. These advances in the development of new blood pumps for patients with CHD will address a significant unmet clinical need, as well as generally improve innovation of the current state of the art in MCS technology.

  17. NON-LIPID MECHANISMS OF STATINS ACTION FOR HEART TRANSPLANT RECIPIENTS

    Directory of Open Access Journals (Sweden)

    А. О. Shevchenko

    2013-01-01

    Full Text Available Statins are widely used in the treatment of heart transplant recipients. It is assumed that the effectiveness of statins after heart transplantation is due not only to hypolipidemic effects, but also to non-lipid effects, including anti-inflammato- ry. In the review are presented the recently published results of the pro-and retrospective studies on the role of statins in the treatment of post-heart transplant recipients. Also there were analyzed the immunomodulatory and anti-in- flammatory mechanisms based on reduced levels of C-reactive protein, decreased concentration of cytokines (TNF-α, IL-6, IL-2R, suppression of tissue factor expression by monocytes etc. Another important factor is the role of statins in reducing the risk of cancer for transplant recipients. The use of statins in the treatment with immunosuppressive agents is an important factor in optimizing the long-term outcomes, reduction in the incidence of acute rejection and coronary artery disease of transplanted heart, increasing the duration and quality of life for heart transplant recipients. 

  18. Fast Simulation of Mechanical Heterogeneity in the Electrically Asynchronous Heart Using the MultiPatch Module.

    Directory of Open Access Journals (Sweden)

    John Walmsley

    2015-07-01

    Full Text Available Cardiac electrical asynchrony occurs as a result of cardiac pacing or conduction disorders such as left bundle-branch block (LBBB. Electrically asynchronous activation causes myocardial contraction heterogeneity that can be detrimental for cardiac function. Computational models provide a tool for understanding pathological consequences of dyssynchronous contraction. Simulations of mechanical dyssynchrony within the heart are typically performed using the finite element method, whose computational intensity may present an obstacle to clinical deployment of patient-specific models. We present an alternative based on the CircAdapt lumped-parameter model of the heart and circulatory system, called the MultiPatch module. Cardiac walls are subdivided into an arbitrary number of patches of homogeneous tissue. Tissue properties and activation time can differ between patches. All patches within a wall share a common wall tension and curvature. Consequently, spatial location within the wall is not required to calculate deformation in a patch. We test the hypothesis that activation time is more important than tissue location for determining mechanical deformation in asynchronous hearts. We perform simulations representing an experimental study of myocardial deformation induced by ventricular pacing, and a patient with LBBB and heart failure using endocardial recordings of electrical activation, wall volumes, and end-diastolic volumes. Direct comparison between simulated and experimental strain patterns shows both qualitative and quantitative agreement between model fibre strain and experimental circumferential strain in terms of shortening and rebound stretch during ejection. Local myofibre strain in the patient simulation shows qualitative agreement with circumferential strain patterns observed in the patient using tagged MRI. We conclude that the MultiPatch module produces realistic regional deformation patterns in the asynchronous heart and that

  19. Ultrastructure of Cardiomyocytes and Blood Capillary Endotheliocytes in the Myocardium under Conditions of Experimental Mechanical Injury to the Heart.

    Science.gov (United States)

    Novoselov, V P; Savchenko, S V; Porvin, A N; Koshlyak, D A; Nadev, A P; Ageeva, T A; Chikinev, Yu V; Polyakevich, A S

    2016-05-01

    We studied ultrastructural changes in cardiomyocytes and blood capillary endotheliocytes in the ventricular myocardium in response to mechanical injury of the heart of varying severity in Wistar rats. Acute alterative changes in cardiomyocyte and endotheliocyte ultrastructure indicate impairment of the energy-producing, contractile, and protein-synthesizing functions of the cells after mechanical injury. These disorders play the key role in the development of acute contractile insufficiency of the myocardium in mechanical injury to the heart.

  20. Frank-Starling mechanism retains recirculation fraction of myocardial Ca(2+) in the beating heart.

    Science.gov (United States)

    Mizuno, J; Araki, J; Mohri, S; Minami, H; Doi, Y; Fujinaka, W; Miyaji, K; Kiyooka, T; Oshima, Y; Iribe, G; Hirakawa, M; Suga, H

    2001-12-01

    Myocardial Ca(2+) handling in excitation-contraction coupling is the second primary determinant of energy or O(2) demand in a working heart. The intracellular and extracellular routes remove myocardial Ca(2+) that was released into the sarcoplasma with different Ca(2+): ATP stoichiometries. The intracellular route is twice as economical as the extracellular route. Therefore the fraction of total Ca(2+) removed via the sarcoplasmic reticulum, i.e., the recirculation fraction of intracellular Ca(2+) (RF), determines the economy of myocardial Ca(2+) handling. RF has conventionally been estimated as the exponential decay rate of postextrasystolic potentiation (PESP). However, we have found that PESP usually decays in alternans, but not exponentially in the canine left ventricle beating above 100 beats/min. We have succeeded in estimating RF from the exponential decay component of an alternans PESP. We previously found that the Frank-Starling mechanism or varied ventricular preload did not affect the economy of myocardial Ca(2+) handling. Then, to account for this important finding, we hypothesized that the Frank-Starling mechanism would not affect RF at a constant heart rate. We tested this hypothesis and found its supportive evidence in 11 canine left ventricles. We conclude that RF at a constant heart rate would remain constant, independent of the Frank-Starling mechanism.

  1. Arterial wall mechanics as a function of heart rate: role of vascular smooth muscle

    Energy Technology Data Exchange (ETDEWEB)

    Salvucci, Fernando Pablo; Schiavone, Jonathan; Craiem, Damian; Barra, Juan Gabriel [Facultad de Ingenieria y Ciencias Exactas y Naturales, Universidad Favaloro Av. Belgrano 1723 - Buenos Aires (Argentina)

    2007-11-15

    Vascular wall viscoelasticity can be evaluated using a first-order lumped model. This model consists of a spring with elastic constant E and a dashpot with viscous constant {eta}. More importantly, this viscoelastic model can be fitted in-vivo measuring arterial pressure and diameter. The aim of this work is to analyze the influence of heart rate over E and {eta}. In two anesthetized sheep, diameter in thoracic aorta and intravascular pressure has been registered. The right atrium was connected to a programmable stimulator through a pair of pace-maker wires to produce changes in stimulation heart rate (HR) from 80 to 160 bpm. Additionally, local activation of vascular smooth muscle was induced with phenylephrine. After converting pressure and diameter signals into stress and strain respectively, E y {eta} were calculated in control state and during muscle activation. The elastic modulus E did not present significant changes with heart rate. The viscous modulus {eta} decreased 49% with a two-fold acceleration in heart rate from 80 to 160 bpm. However, the product {eta} HR remained stable. The viscous modulus {eta} increased 39% with smooth muscle activation. No significant pressure changes were registered during the experiment. The contractile action of vascular smooth muscle could contribute to increasing arterial wall viscosity. The decrease of {eta} when HR increased might be related to smooth muscle relaxation mediated by endothelium activity, which was stimulated by flow increase. We conclude that HR can modulate arterial wall viscoelasticity through endothelium-dependent mechanisms.

  2. Role of long-term mechanical circulatory support in patients with advanced heart failure.

    Science.gov (United States)

    Stokes, M B; Bergin, P; McGiffin, D

    2016-05-01

    Advanced heart failure represents a small proportion of patients with heart failure that possess high-risk features associated with high hospital readmission rates, significant functional impairment and mortality. Identification of those who have progressed to, or are near a state of advanced heart failure should prompt referral to a service that offers therapies in mechanical circulatory support (MCS) and cardiac transplantation. MCS has grown as a management strategy in the care of these patients, most commonly as a bridge to cardiac transplantation. The predominant utilisation of MCS is implantation of left ventricular assist devices (LVAD), which have evolved significantly in their technology and application over the past 15-20 years. The technology has evolved to such an extent that Destination Therapy is now being utilised as a strategy in management of advanced heart failure in appropriately selected patients. Complication rates have decreased with VAD implantation, but remain a significant consideration in the decision to implant a device, and in the follow up of these patients.

  3. Low-dose copper infusion into the coronary circulation induces acute heart failure in diabetic rats: New mechanism of heart disease.

    Science.gov (United States)

    Cheung, Carlos Chun Ho; Soon, Choong Yee; Chuang, Chia-Lin; Phillips, Anthony R J; Zhang, Shaoping; Cooper, Garth J S

    2015-09-01

    Diabetes impairs copper (Cu) regulation, causing elevated serum Cu and urinary Cu excretion in patients with established cardiovascular disease; it also causes cardiomyopathy and chronic cardiac impairment linked to defective Cu homeostasis in rats. However, the mechanisms that link impaired Cu regulation to cardiac dysfunction in diabetes are incompletely understood. Chronic treatment with triethylenetetramine (TETA), a Cu²⁺-selective chelator, improves cardiac function in diabetic patients, and in rats with heart disease; the latter displayed ∼3-fold elevations in free Cu²⁺ in the coronary effluent when TETA was infused into their coronary arteries. To further study the nature of defective cardiac Cu regulation in diabetes, we employed an isolated-perfused, working-heart model in which we infused micromolar doses of Cu²⁺ into the coronary arteries and measured acute effects on cardiac function in diabetic and non-diabetic-control rats. Infusion of CuCl₂ solutions caused acute dose-dependent cardiac dysfunction in normal hearts. Several measures of baseline cardiac function were impaired in diabetic hearts, and these defects were exacerbated by low-micromolar Cu²⁺ infusion. The response to infused Cu²⁺ was augmented in diabetic hearts, which became defective at lower infusion levels and underwent complete pump failure (cardiac output = 0 ml/min) more often (P hearts. To our knowledge, this is the first report describing the acute effects on cardiac function of pathophysiological elevations in coronary Cu²⁺. The effects of Cu²⁺ infusion occur within minutes in both control and diabetic hearts, which suggests that they are not due to remodelling. Heightened sensitivity to the acute effects of small elevations in Cu²⁺ could contribute substantively to impaired cardiac function in patients with diabetes and is thus identified as a new mechanism of heart disease.

  4. THE RESULTS OF MECHANICAL HEART SUPPORT SYSTEMS «INCOR» IMPLANTATION

    Directory of Open Access Journals (Sweden)

    A. M. Cherniavskiy

    2013-01-01

    Full Text Available The aim of investigation isestimation of mechanical heart support system «INCOR» implantation efficacy. Materials and methods. The Institute of Circulation Pathology has clinical experience of mechanical circulatory support systems «INCOR» (Berlin Heart AG implantation in 12 patients (10 men and 2 women with severe heart failure during the period from November 2006 to October 2012. The main indication for the use of mechanical support of the left ventricle was a left ventricular failure with marked dilatation of the left heart: end-diastolic volume (EDV, LV – 283 ± 58 ml, end-systolic volume (ESV – 233 ± 57 ml, ejection fraction (EF – 16 ± 7%, with preserved function of the right ventricle (RV (RV ejection fraction 35 ± 12%. Results. All patients showed a significant improvement in central hemodynamics in early postoperative period, reducing the volume of the heart chambers: LV EDV from 283 ± 58 to 183 ± 94 ml; LV ESV with 234 ± 57 to 157 ± 65 ml, increased right ventricular ejection fraction (RV EF (from 35 ± 12 to 43 ± 17%. Improve the function of the right ventricle oc- curred mainly due to the expense of left ventricular unloading and pulmonary circulation. In addition, there was a significant improvement in clinical status of patients – regression of symptoms of heart failure, a recovery of the liver and kidney function. Despite the ongoing anticoagulation and antiplatelet therapy under constant parameters of coagulation, there was some complications. Uterine bleeding occurred in 1 patient (16.6%, which required the abolition of anticoagulants and antiplatelet, uterine artery embolization, and as a result has led to thrombosis and stop system «INCOR». Four patients (33.3% had severe thromboembolic complications – acute cerebrovascular accident (CVA. In 1 patient (8% there was a hemorrhagic stroke due to rupture of intracerebral aneurysms with a breakthrough into the lateral ventricle of the brain. In 3 patients (25

  5. Itraconazole decreases left ventricular contractility in isolated rabbit heart: Mechanism of action

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Yusheng, E-mail: yqu@amgen.com [Toxicology Science, Amgen, Inc, One Amgen Center Drive, Thousand Oaks, CA 91320 (United States); Fang, Mei; Gao, BaoXi; Amouzadeh, Hamid R. [Toxicology Science, Amgen, Inc, One Amgen Center Drive, Thousand Oaks, CA 91320 (United States); Li, Nianyu; Narayanan, Padma [Discovery Toxicology, Amgen, Inc, One Amgen Center Drive, Thousand Oaks, CA 91320 (United States); Acton, Paul; Lawrence, Jeff; Vargas, Hugo M. [Toxicology Science, Amgen, Inc, One Amgen Center Drive, Thousand Oaks, CA 91320 (United States)

    2013-04-15

    Itraconazole (ITZ) is an approved antifungal agent that carries a “black box warning” in its label regarding a risk of negative cardiac inotropy based on clinical findings. Since the mechanism of the negative inotropic effect is unknown, we performed a variety of preclinical and mechanistic studies to explore the pharmacological profile of ITZ and understand the negative inotropic mechanism. ITZ was evaluated in: (1) an isolated rabbit heart (IRH) preparation using Langendorff retrograde perfusion; (2) ion channel studies; (3) a rat heart mitochondrial function profiling screen; (4) a mitochondrial membrane potential (MMP) assay; (5) in vitro pharmacology profiling assays (148 receptors, ion channels, transporters, and enzymes); and (6) a kinase selectivity panel (451 kinases). In the IRH, ITZ decreased cardiac contractility (> 30%) at 0.3 μM, with increasing effect at higher concentrations, which indicated a direct negative inotropic effect upon the heart. It also decreased heart rate and coronary flow (≥ 1 μM) and prolonged PR/QRS intervals (3 μM). In mechanistic studies, ITZ inhibited the cardiac NaV channel (IC{sub 50}: 4.2 μM) and was devoid of any functional inhibitory effect at the remaining pharmacological targets. Lastly, ITZ did not affect MMP, nor interfere with mitochondrial enzymes or processes involved with fuel substrate utilization or energy formation. Overall, the cardiovascular and mechanistic data suggest that ITZ-induced negative inotropy is a direct effect on the heart, in addition, the potential involvement of mitochondria function and L-type Ca{sup 2+} channels are eliminated. The exact mechanism underlying the negative inotropy is uncertain, and requires further study. - Highlights: ► Effect of itraconazole (ITZ) was assessed in the isolated rabbit heart (IRH) assay. ► ITZ decreased ventricular contractility in IRH, indicating a direct effect. ► IC{sub 50} of ITZ on L-type I{sub Ca} was greater than 30 μM, on I{sub Na} was 4

  6. Management of abnormal uterine bleeding in women with mechanical heart valve prosthesis and anticoagulant therapy.

    Science.gov (United States)

    Saha, Pradip Kumar; Rakshit, Bibek Mohan; Jana, Narayan; Dutta, Sanjib; Roy, Subesha Basu; Sengupta, Gautam

    2011-12-01

    In a prospective observational case series, we assessed the effects and management and outcome of oral anticoagulant associated abnormal uterine bleeding in women with mechanical heart valve prosthesis. Six women with mechanical heart valve prosthesis, who were admitted with persistent severe vaginal bleeding between 2003 and 2010, were evaluated. For each woman, detailed history, treatment received, if there was any complication and their final outcome and satisfaction were recorded. All the 6 women were parous, with their ages ranging from 27 to 50 years. They were receiving oral anticoagulant therapy for mechanical heart valve prosthesis. Of the 6 women, 4 had uterine fibroids, and the other 2 had dysfunctional uterine bleeding.Three patients with uterine fibroids underwent abdominal hysterectomy, and one underwent balloon thermal ablation of endometrium. While 1 patient with dysfunctional uterine bleeding underwent hysterectomy, the other patient desirous for further children, required levonorgestrel intra-uterine system. Two women requiring hysterectomy, developed postoperative complications, one a massive intraperitoneal haemorrhage and another a rectus sheath haematoma. At follow-up, 5 women were satisfied, and 1 woman had died suddenly at home 1 year after hysterectomy. Because of the twin problem of heart disease and anticoagulant therapy, treatment of abnormal vaginal bleeding in these women is extremely challenging. Although medical treatment yields only temporary relief, endometrial ablative procedures or levonorgestrel intra-uterine system provides more durable solution. As anticoagulant associated peri-operative haemorrhage can be potentially fatal, hysterectomy should be reserved for women with major pelvic pathologies. Proper counselling and integrated management involving gynaecologist, cardiologist, haematologist and anaesthesiologist is essential to tackle this problem.

  7. Relationships between melanocytes, mechanical properties and extracellular matrix composition in mouse heart valves.

    Science.gov (United States)

    Carneiro, Flavia; Kruithof, Boudewijn Pt; Balani, Kanthesh; Agarwal, Arvind; Gaussin, Vinciane; Kos, Lidia

    2015-01-01

    Heart valves are complex structures composed of organized layers of extracellular matrix, and interstitial and overlying endothelial cells. In this article, we present the specific localization of a population of melanocytes within the murine heart valves at ages important for their post-natal development. In all stages analyzed in our study, melanocytes were found in high numbers populating the atrial aspect of the tricuspid and mitral leaflets. The pulmonary valve did not present melanocytes. To characterize a putative role for the valve melanocytes, the dynamic nanomechanical properties of tricuspid leaftets containing large numbers or no melanocytes were measured. The stiffness coefficient of hyperpigmented leaflets was higher (11.5 GPa) than the ones from wild-type (7.5 GPa) and hypopigmented (5.5 GPa) leaflets. These results suggest that melanocytes may contribute to the mechanical properties of the heart valves. The arrangement of extracellular matrix molecules such as Collagen I and Versican B is responsible for the mechanical characteristics of the leaflets. Melanocytes were found to reside primarily in areas of Versican B expression. The patterns of expression of Collagen I and Versican B were not, however, disrupted in hyper or hypopigmented leaflets. Melanocytes may affect other extracellular matrix molecules to alter the valves' microenvironment.

  8. Demikhov's "Mechanical Heart": The Circumstances Surrounding Creation of the World's First Implantable Total Artificial Heart in 1937.

    Science.gov (United States)

    Glyantsev, Sergey P; Tchantchaleishvili, Vakhtang; Bockeria, Leo A

    2016-01-01

    The world's first implantable total artificial heart was designed by Vladimir Demikhov as a fourth year biology student in Voronezh, Soviet Union, in 1937. As a prototype of his device, Demikhov must have used an apparatus for extracorporeal blood circulation invented by Sergei Bryukhonenko of Moscow. The device was the size of a dog's native heart and consisted of two diaphragm pumps brought into motion by an electric motor. A dog with an implanted device lived for 2.5 hours. In addition to having the prototype, the preconditions for Demikhov's artificial heart creation were his manual dexterity, expertise in animal physiology, and his mechanistic worldview.

  9. Multi-scale mechanical characterization of scaffolds for heart valve tissue engineering.

    Science.gov (United States)

    Argento, G; Simonet, M; Oomens, C W J; Baaijens, F P T

    2012-11-15

    Electrospinning is a promising technology to produce scaffolds for cardiovascular tissue engineering. Each electrospun scaffold is characterized by a complex micro-scale structure that is responsible for its macroscopic mechanical behavior. In this study, we focus on the development and the validation of a computational micro-scale model that takes into account the structural features of the electrospun material, and is suitable for studying the multi-scale scaffold mechanics. We show that the computational tool developed is able to describe and predict the mechanical behavior of electrospun scaffolds characterized by different microstructures. Moreover, we explore the global mechanical properties of valve-shaped scaffolds with different microstructural features, and compare the deformation of these scaffolds when submitted to diastolic pressures with a tissue engineered and a native valve. It is shown that a pronounced degree of anisotropy is necessary to reproduce the deformation patterns observed in the native heart valve.

  10. Anticoagulant independent mechanical heart valves: viable now or still a distant holy grail.

    Science.gov (United States)

    Chaux, Aurelio; Gray, Richard J; Stupka, Jonathan C; Emken, Michael R; Scotten, Lawrence N; Siegel, Rolland

    2016-12-01

    Valvular heart disease remains a large public health problem for all societies; it attracts the attention of public health organizations, researchers and governments. Valve substitution is an integral part of the treatment for this condition. At present, the choice of valve prosthesis is either tissue or mechanical. Tissue valves have become increasingly popular in spite of unresolved problems with durability, hemodynamics, cost and need for anticoagulation therapy. As a consequence, mechanical valve innovation has virtually ceased; the last successful mechanical design is 25 years old. We postulate that with improved technology, knowledge and experience gained over the last quarter century, the best possible solution to the problem of valve substitution can be achieved with a mechanical valve that is anticoagulant independent, durable, hemodynamically and cost efficient. At present, it is possible to design, test and produce a valve that can accomplish these goals.

  11. Mechanism of cardioprotective effect of erythropoietin-induced preconditioning in rat heart

    Directory of Open Access Journals (Sweden)

    Garg Kavita

    2010-01-01

    Full Text Available Objective : The cardioprotective potential of human recombinant erythropoietin (alpha (Epo against ischemia-reperfusion-induced injury is well known. But, the underlying mechanisms are not well elucidated. The aim of this study was to characterize the mechanism involved in the cardioprotective effect of Epo-induced preconditioning in isolated rat heart. Materials and Methods : The heart was mounted on a Langendorff apparatus. After 10 min of stabilization, four cycles of ischemic preconditioning (IPC were given followed by 30 min of global ischemia and 120 min of reperfusion. Epo preconditioning was induced by four cycles of 5-min perfusion of K-H solution containing Epo (1.0 U/ml followed by 5 min perfusion with K-H solution. Myocardial infarct size was estimated macroscopically using the triphenyltetrazolium chloride staining technique. The extent of myocardial injury was measured by release of lactate dehydrogenase and creatine kinase-MB in the coronary effluent. Results : The present study demonstrates that Epo preconditioning was almost as effective as IPC. Administration of Wortmannin (100 nM, a PI-3K inhibitor, or Chelerythrine (1 μM, a protein kinase-C (PKC inhibitor, or AG490 (5 μM, a JAK-2 inhibitor, significantly attenuated the cardioprotective effects of Epo-induced preconditioning. Conclusion : Our result suggest that the cardioprotective potential of Epo-induced preconditioning in isolated rat heart was due to an interplay of the JAK-2, PI-3K and PKC pathways. Inhibition of any one of the three pathways was sufficient to block the cardioprotective effect of Epo-induced preconditioning in isolated rat heart.

  12. Mitigation Effect of Proanthocyanidin on Secondary Heart Injury in Rats Caused by Mechanical Trauma

    Science.gov (United States)

    Ma, Shuo; Chen, Chong; Cao, Tingting; Bi, Yue; Zhou, Jicheng; Li, Xintao; Yu, Deqin; Li, Shuzhuang

    2017-01-01

    Multiple organ dysfunctional syndrome secondary to mechanical trauma (MT) has attracted considerable research attention. The heart is one of the most important organs of the body, and secondary cardiac insufficiency caused by MT seriously affects the quality of life. This study aims to investigate whether proanthocyanidin can alleviate myocardial injury and improve heart function in the process of MT leading to secondary cardiac insufficiency. Noble-Collip drum wasused to prepare MT model in rats. And myocardial apoptosis index was calculated after TUNEL staining. Ventricular intubation was employed to detect heart function. Changes in myocardial ultrastructure were observed using an electron microscope. ELISA was used to detect the content of TNF-α and reactive oxygen species generated from monocytes and cardiomyocytes. The changes in Ca2+ concentration in cardiomyocyte were observed by confocal microscope. Compared with trauma group, the administration group had a decreased apoptosis index of cardiomyocytes, and increased ±dp/dtmax. Meanwhile, proanthocyanidin can inhibit monocytes’ TNF-α production, and reduce plasma TNF-α concentration. Moreover, proanthocyanidin can attenuate the excessive oxidative stress reaction of cardiomyocyte, and inhibit calcium overload in cardiomyocytes. In conclusion, proanthocyanidin can effectively ease myocardial damage and improve cardiac function, through anti-inflammatory and antioxidant effects in secondary cardiac insufficiency caused by MT. PMID:28294148

  13. Experience with enoxaparin in patients with mechanical heart valves who must withhold acenocumarol

    Science.gov (United States)

    Ferreira, I; Dos, L; Tornos, P; Nicolau, I; Permanyer-Miralda, G; Soler-Soler, J

    2003-01-01

    Objectives: To evaluate the incidence of thromboembolic and haemorrhagic events in a cohort of patients with mechanical heart valves who had to withhold acenocumarol and were treated with enoxaparin. Design: Observational prospective study. Setting: In hospital; after discharge, and follow up by telephone call. Patients and methods: All consecutive patients with mechanical heart valves admitted to the authors’ hospital between May 1999 and January 2002 who had to interrupt treatment with acenocumarol and were treated with enoxaparin as an alternative to other methods were enrolled. In each patient, the following characteristics were prospectively determined: the reason for interrupting acenocumarol, demographic data, estimated global risk for thromboembolic events, international normalised ratio before starting enoxaparin treatment, number of days taking enoxaparin, and mean level of anti-Xa activity during treatment. All patients were followed up through clinical history during the hospitalisation and by telephone after discharge to detect thromboembolic events. Main outcome measure: Presence of thromboembolic or haemorrhagic events. Results: 82 patients were identified and followed up for a mean of 2.8 months (range 1.5–3.5 months) after discharge. 61 of them (74%) had one or more associated thromboembolic risk factors. Acenocumarol was interrupted (to perform an invasive procedure in 74 patients and because of haemorrhagic complication in 8) an average of 11.2 days (range 3–40 days). Most patients received the standard enoxaparin dose (1 mg/kg at 12 hour intervals). Mean (SD) anti-Xa activity was 0.58 (0.3) IU/ml (median 0.51). There were 8 minor and 1 major bleeding events during enoxaparin treatment. No thromboembolic complications were clinically detected during hospitalisation or during follow up (95% confidence interval 0% to 3.6%). Conclusions: Enoxaparin may be an effective and relatively safe substitute anticoagulant for patients with mechanical

  14. Univariate Risk Factors for Prolonged Mechanical Ventilation in Patients Undergoing Prosthetic Heart Valves Replacement Surgery

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Data from 736 patients undergoing prosthetic heart valve replacement surgery and concomitant surgery (combined surgery) from January 1998 to January 2004 at Union Hospital were retrospectively reviewed. Univariate logistic regression analyses were conducted to identify risk factors for prolonged mechanical ventilation. The results showed that prolonged cardiopulmonary bypass duration, prolonged aortic cross clamp time and low ejection fraction less than 50 percent (50 %)were found to be independent predictors for prolonged mechanical ventilation. Meanwhile age,weight, and preoperative hospital stay (days) were not found to be associated with prolonged mechanical ventilation. It was concluded that, for age and weight, this might be due to the lower number of old age patients (70 years and above) included in our study and genetic body structure of majority Chinese population that favor them to be in normal weight, respectively.

  15. Cavitation behavior observed in three monoleaflet mechanical heart valves under accelerated testing conditions.

    Science.gov (United States)

    Lo, Chi-Wen; Liu, Jia-Shing; Li, Chi-Pei; Lu, Po-Chien; Hwang, Ned H

    2008-01-01

    Accelerated testing provides a substantial amount of data on mechanical heart valve durability in a short period of time, but such conditions may not accurately reflect in vivo performance. Cavitation, which occurs during mechanical heart valve closure when local flow field pressure decreases below vapor pressure, is thought to play a role in valve damage under accelerated conditions. The underlying flow dynamics and mechanisms behind cavitation bubble formation are poorly understood. Under physiologic conditions, random perivalvular cavitation is difficult to capture. We applied accelerated testing at a pulse rate of 600 bpm and transvalvular pressure of 120 mm Hg, with synchronized videographs and high-frequency pressure measurements, to study cavitation of the Medtronic Hall Standard (MHS), Medtronic Hall D-16 (MHD), and Omni Carbon (OC) valves. Results showed cavitation bubbles between 340 and 360 micros after leaflet/housing impact of the MHS, MHD, and OC valves, intensified by significant leaflet rebound. Squeeze flow, Venturi, and water hammer effects each contributed to cavitation, depending on valve design.

  16. Analysis of electrolyte abnormalities and the mechanisms leading to arrhythmias in heart failure. A literature review.

    Science.gov (United States)

    Urso, C; Canino, B; Brucculeri, S; Firenze, A; Caimi, G

    2016-01-01

    About 50% of deaths from heart failure (HF) are sudden, presumably referable to arrhythmias. Electrolyte and acid-base abnormalities are a frequent and potentially dangerous complication in HF patients. Their incidence is almost always correlated with the severity of cardiac dysfunction; furthermore leading to arrhythmias, these imbalances are associated with a poor prognosis. The frequency of ventricular ectopic beats and sudden cardiac death correlate with both plasma and whole body levels of potassium, especially in alkalemia. The early recognition of these alterations and the knowledge of the pathophysiological mechanisms are useful for the management of these HF patients.

  17. End-stage heart failure and mechanical circulatory support: feasibility of discharge from hospital.

    Science.gov (United States)

    Oosterom, A; de Jonge, N; Kirkels, J H; Rodermans, B F M; Sukkel, E; Klöpping, C; Ramjankhan, F; Lahpor, J R

    2007-01-01

    BACKGROUND.: Due to the shortage of donor hearts, mechanical circulatory support is increasingly being used as a bridge to transplantation. In order to allow for more widespread use of ventricular assist devices it is mandatory that patients are not continuously hospitalised. We present the results of our experience with patients with end-stage heart failure, discharged from hospital after implantation of a ventricular assist device and followed in an outpatient setting. METHODS.: After an intensive training and education programme, focusing on the management of the percutaneous driveline and instructions on how to handle in case of an alarm or malfunction of the device, patients were discharged. They were followed in the outpatient department. All regular and unplanned visits were registered, including readmissions. RESULTS.: Twenty-seven patients treated with a ventricular assist device were discharged from hospital. There were 37 extra visits, of these, 27 were device related resulting in 21 readmissions (0.78/patient). We treated eight infectious episodes in four patients, all device related. Furthermore seven thromboembolic episodes occurred in four patients. One patient died because of multiorgan failure seven weeks after he was readmitted with an urosepsis. In our experience of 11.4 patient years at home while on the device, only 5% of the time was spent in hospital for complications. In comparison with patients on an assist device who stayed in hospital until transplantation, there were no more complications. CONCLUSION.: This study demonstrates that patients with end-stage heart failure, treated with a ventricular assist device, can be safely discharged from hospital, with an acceptable rate of readmissions. It results in a fair quality of life, with a high degree of independence of the patient. (Neth Heart J 2007;15:45-50.).

  18. Mechanism of the negative inotropic effect of naringin in mouse heart.

    Directory of Open Access Journals (Sweden)

    Julio Alvarez-Collazo

    2014-10-01

    Full Text Available Context: Naringin (NRG is the major flavonoid (flavanone glycoside in grapefruit juice. Its biological activity has been only partially characterized and little is known about the mechanism of the negative inotropic action of this flavonoid. Aims: To evaluate the effects of NRG on the surface electrogram (ECG and the force of contraction (FC of mice hearts as well as on the sodium (INa, calcium (ICaL and Na+ – Ca2+ exchange (INaCaX currents of enzymatically isolated mouse ventricular cardiomyocytes. Methods: ECG and FC were recorded on mouse hearts perfused in a Langendorff column. Ventricular cardiomyocytes were enzimatically dissociated and ionic currents recorded with the patch-clamp technique. Results: NRG increased RR interval and shortened corrected QT only at high concentrations (30-100 µM. However, at a fixed heart rate, it decreased FC with an IC50 of 0.4 µM. NRG reduced INa with an IC50 of 0.07 µM but with a maximal inhibition of 60 %. NRG also depressed ICaL with an IC50 of 0.013 µM and increased its fast inactivation time constant. The effects on ICaL were not voltage-dependent. INaCaX was not affected by NRG. Conclusions: Our results indicate that NRG exerts a negative inotropic effect in mice hearts that could be explained by a decrease in INa and ICaL. These actions should be taken into account when considering this molecule either as a dietetic supplement or as a template to develop therapeutic agents for human diseases.

  19. Exhaustion of Frank-Starling mechanism in conscious dogs with heart failure.

    Science.gov (United States)

    Komamura, K; Shannon, R P; Ihara, T; Shen, Y T; Mirsky, I; Bishop, S P; Vatner, S F

    1993-10-01

    The goal of this study was to elucidate the ability of the left ventricle to accommodate an increase in preload (Frank-Starling mechanism) in the presence of congestive heart failure (CHF) but in the absence of the complicating effects of hypertrophy and fibrosis. To accomplish this, the effects of volume loading were examined in eight conscious dogs during the control state and after 3 wk of right ventricular pacing (240 beats/min). CHF increased heart rate (by 16 +/- 5 from 92 +/- 5 beats/min), left ventricular (LV) end-diastolic pressure (by 17 +/- 2 from 10 +/- 1 mmHg), and LV end-diastolic volume (EDV; by 23 +/- 4 from 57 +/- 3 ml). Despite reduced LV ejection fraction (from 54 +/- 3 to 31 +/- 3%), there was no significant change in cardiac output (2.5 +/- 0.3 l/min) compared with control (2.7 +/- 0.2 l/min). Stroke volume was preserved (control 19 +/- 2 ml; CHF 18 +/- 2 ml) at a constant heart rate by a shift to the right in the relationship between LV stroke volume and EDV, indicating the importance of chronic ventricular dilatation in maintaining pump performance. In the control state, acute volume load increased LV EDV (by 17 +/- 2 ml) and stroke volume (by 11 +/- 2 ml), whereas in CHF it did not increase LV EDV or stroke volume. Scanning electron microscopy revealed areas of reduced collagen weave pattern surrounding myofibers. Myocyte cross-sectional area by transmission electron microscopy was significantly reduced, and there were multiple electron-dense expansions of the Z lines with disruption of the normal lateral sarcomere alignment. These morphological findings suggest that chronic ventricular dilatation utilized in CHF results from myocyte stretch and morphological intracellular rearrangement. Furthermore, the failing heart cannot further augment stroke volume by acutely increasing EDV in CHF, suggesting that the Frank-Starling reserve is essentially exhausted.

  20. 人造机械瓣心音的分析研究%Analysis of Heart Sounds with Artificial Mechanical Prosthetic Heart Valves

    Institute of Scientific and Technical Information of China (English)

    张地; 姚尖平; 杜明辉; 杨嵩

    2011-01-01

    在一些致命性心脏病的诊断中,心音听诊是最有效也是应用得最成功的手段之一.鉴于目前机械瓣的使用非常普遍,研究简单有效的机械瓣病变判别方法对于临床诊断来讲具有重要意义.运用希尔波特-黄变换(HHT),针对不同的机械瓣心音进行分析,并设计一种基于Hilbert边界谱特征的提取方法,结合线性判别分析(LDA),对不同的机械瓣心音进行分类.同时,与基于局部最优基特征的分类器分类结果进行比较.分析结果表明,机械瓣心音的各阶Hilbert边界谱具有非常明显不同的分布,基于HHT的分类器识别率达到了97.3%,较基于局部最优基特征分类器的识别率(91.3%)更高.对于人造机械瓣心音而言,HHT是一种有效的分析处理手段.%Auscultation is a widely used efficient technique by cardiologists for detecting some deadly heart diseases. Since the mechanical prosthetic heart valves are widely used today, it is important to develop a simple and efficient method to detect abnormal mechanical valves. In this paper, Hilbert-Huang transform ( HHT) was applied to analyze the heart sounds with different kinds of mechanical prosthetic valves. A Hilbert marginal spectral based feature extraction procedure was also developed. Combined with linear discriminant analysis ( LDA) , the extracted features were used to classify different kinds of heart sounds for mechanical prosthetic heart valves. Experimental results showed that the spectrum of different heart sounds were significantly different. The proposed classifier achieved a recognition rate of 97. 3% , higher than the one based on local discriminant bases (91. 3% ). It is demonstrated that HHT is an efficient analyzing technique for artificial heart valve sounds.

  1. Mechanism-based modeling of reduced inotropic responsiveness to digoxin in endotoxemic rat hearts.

    Science.gov (United States)

    Baek, Myoungki; Weiss, Michael

    2005-05-02

    The mechanisms by which endotoxemia affects myocardial contractility and responsiveness to inotropic drugs are not well understood. We examined the positive inotropic effect of digoxin in single-pass Langendorff-perfused hearts from rats after in vivo pretreatment with lipopolysaccharide (LPS, 4 mg/kg, i.p., 4 h before heart isolation). Using a mathematical modeling approach that allows differentiation between effects elicited at the receptor and postreceptor level, we studied uptake, receptor binding and effectuation kinetics after three consecutive digoxin doses (15, 30, and 45 microg) in the absence and presence of the reverse mode Na(+)/Ca(2+) exchange (NCX) inhibitor KB-R7943 (0.1 microM) in perfusate. LPS significantly depressed baseline contractility and the inotropic response to digoxin without affecting its uptake mechanism. Compared with the control group, the slope of the functional receptor occupancy (stimulus)-to-response relationship was reduced by 44% in the LPS group. Model analysis revealed a significant correlation between changes in digoxin action and LPS-induced febrile response: digoxin receptor affinity increased and the response/stimulus ratio decreased with rise in body temperature, respectively. In contrast, the diminished responsiveness to digoxin observed after NCX inhibition in the control group was not further attenuated in the LPS group. These results support the hypothesis that postreceptor events may be responsible for the diminished contractile response to digoxin during endotoxemia.

  2. Heart rate reduction with ivabradine promotes shear stress-dependent anti-inflammatory mechanisms in arteries.

    Science.gov (United States)

    Luong, Le; Duckles, Hayley; Schenkel, Torsten; Mahmoud, Marwa; Tremoleda, Jordi L; Wylezinska-Arridge, Marzena; Ali, Majid; Bowden, Neil P; Villa-Uriol, Mari-Cruz; van der Heiden, Kim; Xing, Ruoyu; Gijsen, Frank J; Wentzel, Jolanda; Lawrie, Allan; Feng, Shuang; Arnold, Nadine; Gsell, Willy; Lungu, Angela; Hose, Rodney; Spencer, Tim; Halliday, Ian; Ridger, Victoria; Evans, Paul C

    2016-07-04

    Blood flow generates wall shear stress (WSS) which alters endothelial cell (EC) function. Low WSS promotes vascular inflammation and atherosclerosis whereas high uniform WSS is protective. Ivabradine decreases heart rate leading to altered haemodynamics. Besides its cardio-protective effects, ivabradine protects arteries from inflammation and atherosclerosis via unknown mechanisms. We hypothesised that ivabradine protects arteries by increasing WSS to reduce vascular inflammation. Hypercholesterolaemic mice were treated with ivabradine for seven weeks in drinking water or remained untreated as a control. En face immunostaining demonstrated that treatment with ivabradine reduced the expression of pro-inflammatory VCAM-1 (pivabradine alters EC physiology indirectly via modulation of flow because treatment with ivabradine had no effect in ligated carotid arteries in vivo, and did not influence the basal or TNFα-induced expression of inflammatory (VCAM-1, MCP-1) or protective (eNOS, HMOX1, KLF2, KLF4) genes in cultured EC. We therefore considered whether ivabradine can alter WSS which is a regulator of EC inflammatory activation. Computational fluid dynamics demonstrated that ivabradine treatment reduced heart rate by 20 % and enhanced WSS in the aorta. In conclusion, ivabradine treatment altered haemodynamics in the murine aorta by increasing the magnitude of shear stress. This was accompanied by induction of eNOS and suppression of VCAM-1, whereas ivabradine did not alter EC that could not respond to flow. Thus ivabradine protects arteries by altering local mechanical conditions to trigger an anti-inflammatory response.

  3. Exhaustion of the Frank-Starling mechanism in conscious dogs with heart failure induced by chronic coronary microembolization.

    Science.gov (United States)

    Gill, Robert M; Jones, Bonita D; Corbly, Angela K; Ohad, Dan G; Smith, Gerald D; Sandusky, George E; Christe, Michael E; Wang, Jie; Shen, Weiqun

    2006-07-04

    The role of the Frank-Starling mechanism in the regulation of cardiac systolic function in the ischemic failing heart was examined in conscious dogs. Left ventricular (LV) dimension, pressure and systolic function were assessed using surgically implanted instrumentations and non-invasive echocardiogram. Heart failure was induced by daily intra-coronary injections of microspheres for 3-4 weeks via implanted coronary catheters. Chronic coronary embolization resulted in a progressive dilation of the left ventricle (12+/-3%), increase in LV end-diastolic pressure (118+/-19%), depression of LV dP/dt(max) (-19+/-4%), fractional shortening (-36+/-7%), and cardiac work (-60+/-9%), and development of heart failure, while the LV contractile response to dobutamine was depressed. A brief inferior vena caval occlusion in dogs with heart failure decreased LV preload to match the levels attained in their control state and caused a further reduction of LV dP/dt(max), fractional shortening, stroke work and cardiac work. Moreover, in response to acute volume loading, the change in the LV end-diastolic dimension-pressure (DeltaLVEDD-DeltaLVEDP) curve in the failing heart became steeper and shifted significantly to the left, while the increases in LV stroke work and cardiac work were blunted. Thus, our results suggest that the Frank-Starling mechanism is exhausted in heart failure and unable to further respond to increasing volume while it plays an important compensatory role in adaptation to LV dysfunction in heart failure.

  4. Heart failure with normal ejection fraction: consideration of mechanisms other than diastolic dysfunction.

    Science.gov (United States)

    Bench, Travis; Burkhoff, Daniel; O'Connell, John B; Costanzo, Maria Rosa; Abraham, William T; St John Sutton, Martin; Maurer, Mathew S

    2009-03-01

    More than half of patients with heart failure (HF) have a normal ejection fraction (EF). These patients are typically elderly, are predominantly female, and have a high incidence of multiple comorbid conditions associated with development of ventricular hypertrophy and/or interstitial fibrosis. Thus, the cause of HF has been attributed to diastolic dysfunction. However, the same comorbidities may also impact myocardial systolic, ventricular, vascular, renal, and extracardiovascular properties in ways that can also contribute to symptoms of HF by way of mechanisms not related to diastolic dysfunction. Accordingly, the descriptive term HF with normal EF has been suggested as an alternative to the mechanistic term diastolic HF. In this article, we review the current understanding of nondiastolic mechanisms that may contribute to the HF with normal EF syndrome to highlight potential pathways for research that may lead to new targets for therapy.

  5. Role of the giant elastic protein titin in the Frank-Starling mechanism of the heart.

    Science.gov (United States)

    Fukuda, Norio; Granzier, Henk

    2004-04-01

    Increased ventricular volume enhances the systolic performance, a phenomenon known as Frank-Starling's law of the heart. At its basis is the ability of cardiac muscle to produce increased active force in response to increased muscle length. Although numerous studies have been conducted to elucidate the molecular basis of length-dependent activation, the mechanism remains elusive. The giant protein titin (also known as connectin) is the third filament system in the sarcomere and is responsible for most passive stiffness of striated muscle in the physiological sarcomere length range. The force generated by titin is usually seen as passive and independent of active force generation. Recent findings, however, suggest that titin-based passive force modulates actin-myosin interaction, resulting in greater active force in response to stretch. In this short review, we discuss the molecular mechanisms of length-dependent activation, focusing on the possible role of titin in its regulation.

  6. Outcome of left heart mechanical valve replacement in West African children - A 15-year retrospective study

    Directory of Open Access Journals (Sweden)

    Tamatey Martin

    2011-04-01

    Full Text Available Abstract Background The West African sub-region has poor health infrastructure. Mechanical valve replacement in children from such regions raises important postoperative concerns; among these, valve-related morbidity and complications of lifelong anticoagulation are foremost. Little is known about the long-term outcome of mechanical valve replacement in West Africa. We sought to determine the outcome of mechanical valve replacement of the left heart in children from this sub-region. Method We conducted a retrospective review of all consecutive left heart valve replacements in children ( Results One hundred and fourteen patients underwent mitral valve replacement (MVR, aortic valve replacement (AVR or mitral and aortic valve replacements (MAVR. Their ages ranged from 6-18 years (13.3 ± 3.1 years. All patients were in NYHA class III or IV. Median follow up was 9.1 years. MVR was performed in 91 (79.8% patients, AVR in 13 (11.4% and MAVR in 10 (8.8% patients. Tricuspid valve repair was performed concomitantly in 45 (39.5% patients. There were 6 (5.3% early deaths and 6 (5.3% late deaths. Preoperative left ventricular dysfunction (ejection fraction Conclusion Mechanical valve replacement in West African children has excellent outcomes in terms of mortality, valve-related events, and reoperation rate. Preoperative left ventricular dysfunction is the primary determinant of mortality within the first 2 years of valve replacement. The risk of valve-related complications is acceptably low. Anticoagulation is well tolerated with a very low risk of bleeding even in this socioeconomic setting.

  7. Válvula cardíaca de carbono de duplo folheto Biplus: projeto e desenvolvimento Biplus bileaflet carbon cardiac valve: project and development

    Directory of Open Access Journals (Sweden)

    Hélio Pereira de Magalhães

    1996-12-01

    uso clínico. CONCLUSÕES: A válvula de dois folhetos Biplus apresentou-se com desenho adequado para receber o material biológico e, também, para funcionar com batente de silicone, deixando a válvula bastante silenciosa, para melhor conforto do paciente.INTRODUCTION: After the development of carbon cardiac disc valve covered with heterologous pericardium with good clinical results after two years, the authors developed the first brazilian carbon bileaflet valve. The finality was to have a valve with low level of noise, recovered with biological material for improving the annulus valve healing and reduce the exposed synthetic material in blood stream. Linning the valve with biologic material is a tentative to reduce the morbidity and mortality on respect of thrombosis, thromboembolism, reoperations and minor use of anticoagulants to reduce the haemorrhagic events. Some principles were established on hybrid valve: durable mechanical system, points of contact without biologic material, use of biologic material with minor organic reaction, preferential closing system with superposition on a track seat and loose points for accept biologic material limited growth. MATERIAL AND METHODS: The bileaflet valve has horizontal closing with points of articulation in the internal face of valve ring, made of CARBOLITE (hardened polymeric carbon. The valve is made in three models: only in carbon (equal to other valves, one model recovered with biologic material and a model with silicone elastomer track seat recovered with heterologous pericardium, intended to be noiseless, conserved in glycerin. There are two aortic patients with the second model with two and three months of evolution with oral anticoagulations. RESULTS: The cases have a short time of evolution with good results. The model with silicone elastomer track seat is in fatigue test system and does not have any rupture after 30 days, equivalent to 1.4 years of clinic use. CONCLUSIONS: The Biplus valve shows adequate

  8. Analysis of the Influence of the Electrical Asynchrony on Regional Mechanics of the Infarcted Left Ventricle Using Electromechanical Heart Models

    Science.gov (United States)

    Liu, Feng; Xia, Ling; Zhang, Xin

    Asynchronous electrical activation, as induced by myocardial infarction, causes various abnormalities in left ventricle function. The influence of the electrical asynchrony on regional mechanics of the left ventricle is simulated using a mechanical heart model and an electrical heart model. The mechanical model accounts for the ventricular geometry, the fiber nature of the myocardial tissue, and the dependency of the activation sequence of the ventricular wall. The electrical model is based on a heart-torso model with realistic geometry, and different action potential waveforms with variables in duration are used to simulate the abnormal electrical activation after myocardial infarction. Regional deformation, strain and stress are calculated during systole phase. The preliminary results show that asynchronous electrical activation, as an important factor, significantly affects regional mechanical performance of the infarcted left ventricle, it indicates heterogeneous contraction pattern and elevated systolic stresses near the injured region. The simulated results are compared with solutions obtained in the literature. This simulation suggests that such coupled heart models can be used to assess the mechanical function of the left ventricle with diseases such as myocardial infarction, and more realistic models of cardiac function are essential for clinical evaluation of heart disease.

  9. Titin/connectin-based modulation of the Frank-Starling mechanism of the heart.

    Science.gov (United States)

    Fukuda, Norio; Granzier, Henk L

    2005-01-01

    The basis of the Frank-Starling mechanism of the heart is the increase in active force when muscle is stretched. Various findings have shown that muscle length, i.e., sarcomere length (SL), modulates activation of cardiac myofilaments at a given concentration of Ca2+ ([Ca2+]). This augmented Ca2+ activation with SL, commonly known as "length-dependent activation", is manifested as the leftward shift of the force-pCa (= -log [Ca2+]) relation as well as by the increase in maximal Ca2+ -activated force. Despite the numerous studies that have been undertaken, the molecular mechanism(s) of length-dependent activation is (are) still not fully understood. The giant sarcomere protein titin/connectin is the largest protein known to date. Titin/connectin is responsible for most passive force in vertebrate striated muscle and also functions as a molecular scaffold during myofibrillogenesis. Recent studies suggest that titin/connectin plays an important role in length-dependent activation by sensing stretch and promoting actomyosin interaction. Here we review and extend this previous work and focus on the mechanism by which titin/connectin might modulate actomyosin interaction.

  10. Heart Rate Variability: New Perspectives on Physiological Mechanisms, Assessment of Self-regulatory Capacity, and Health risk.

    Science.gov (United States)

    McCraty, Rollin; Shaffer, Fred

    2015-01-01

    Heart rate variability, the change in the time intervals between adjacent heartbeats, is an emergent property of interdependent regulatory systems that operates on different time scales to adapt to environmental and psychological challenges. This article briefly reviews neural regulation of the heart and offers some new perspectives on mechanisms underlying the very low frequency rhythm of heart rate variability. Interpretation of heart rate variability rhythms in the context of health risk and physiological and psychological self-regulatory capacity assessment is discussed. The cardiovascular regulatory centers in the spinal cord and medulla integrate inputs from higher brain centers with afferent cardiovascular system inputs to adjust heart rate and blood pressure via sympathetic and parasympathetic efferent pathways. We also discuss the intrinsic cardiac nervous system and the heart-brain connection pathways, through which afferent information can influence activity in the subcortical, frontocortical, and motor cortex areas. In addition, the use of real-time HRV feedback to increase self-regulatory capacity is reviewed. We conclude that the heart's rhythms are characterized by both complexity and stability over longer time scales that reflect both physiological and psychological functional status of these internal self-regulatory systems.

  11. Heart Conditions and Pregnancy: Know the Risks

    Science.gov (United States)

    ... concern. Heart valve issues. If you have an artificial heart valve or your heart or valves are scarred ... lining of the heart and heart valves. Mechanical artificial heart valves also pose serious risks during pregnancy due ...

  12. Glycyrrhizic Acid Reduces Heart Rate and Blood Pressure by a Dual Mechanism

    OpenAIRE

    Kailash Singh; Aung Moe Zaw; Revathi Sekar; Ahuja Palak; Allam, Ahmed A.; Jamaan Ajarem; Chow, Billy K. C.

    2016-01-01

    Beta adrenergic receptors are crucial for their role in rhythmic contraction of heart along with their role in the pathological conditions such as tachycardia and high risk of heart failure. Studies report that the levels of beta-1 adrenergic receptor tend to decrease by 50%, whereas, the levels of beta-2 adrenergic receptor remains constant during the risk of heart failure. Beta blockers—the antagonistic molecules for beta-adrenergic receptors, function by slowing the heart rate, which there...

  13. Edema mechanisms in the patient with heart failure and treatment options.

    Science.gov (United States)

    Sica, Domenic A

    2008-10-01

    Volume overload is a common accompanying feature of heart failure. The mechanistic basis for volume overload in heart failure is incompletely worked out. An important component of heart failure treatment remains diuretic therapy. Diuretic dosing remains as much an art as a science with multiple environmental and disease state-related factors influencing the efficiency with which a diuretic works. In heart failure, diuretics should always be given in the lowest possible dose with careful attention to reducing dietary sodium intake.

  14. THE STUDY OF PRODUCTION AND MECHANISM OF ANTIPHOSPHOLIPID ANTIBODIES IN PATIENTS WITH CORONARY HEART DISEASE

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective To assess whether there was strong association between antiphospholipid antibodies(APA) and coronary heart disease(CHD), to study the environmental factors of APA production and APA pathogenic mechanism in patients with CHD.Methods Blood samples from 76 patients with CHD and 30 controls were tested for anticardiolipin antibodies IgG(ACA-IgG),human cytomegalovirus IgG,IgM(HCMV-IgG,IgM) by enzyme-link immunosorbant assay(ELISA) and 6-keto-PGF1a,endothelin(ET) by radioimmunoassay(RIA).Results A total of 27 patients(35.53%) were ACA positive in 76, as compared to 2 of 30(6.67%) healthy individuals, P<0.05. There was no difference in ACA among acute myocardial infarction(AMI,39.13%), old myocardial infarction(OMI,26.53%), unstable angina pectoris(UA,38.40%), P>0.05. The number of ACA positive subjects was higher in HCMV infection patients with CHD than no HCMV infectious patients with CHD. There was no PGI2 and ET level difference between ACA-IgG positive and negative CHD.Conclusion There are strong association between APA and CHD. The HCMV infection may be an environmental factor of APA production in CHD patients with raised ACA. The alteration of PGI2 and ET are not the pathogenic mechanism of ACA in patients with CHD.

  15. the Multitargets Pharmacological Mechanism of Qishenkeli Acting on the Coronary Heart Disease

    Directory of Open Access Journals (Sweden)

    Yong Wang

    2012-01-01

    Full Text Available In this paper, we present a case study of Qishenkeli (QSKL to research TCM’s underlying molecular mechanism, based on drug target prediction and analyses of TCM chemical components and following experimental validation. First, after determining the compositive compounds of QSKL, we use drugCIPHER-CS to predict their potential drug targets. These potential targets are significantly enriched with known cardiovascular disease-related drug targets. Then we find these potential drug targets are significantly enriched in the biological processes of neuroactive ligand-receptor interaction, aminoacyl-tRNA biosynthesis, calcium signaling pathway, glycine, serine and threonine metabolism, and renin-angiotensin system (RAAS, and so on. Then, animal model of coronary heart disease (CHD induced by left anterior descending coronary artery ligation is applied to validate predicted pathway. RAAS pathway is selected as an example, and the results show that QSKL has effect on both rennin and angiotensin II receptor (AT1R, which eventually down regulates the angiotensin II (AngII. Bioinformatics combing with experiment verification can provide a credible and objective method to understand the complicated multitargets mechanism for Chinese herbal formula.

  16. Titin and troponin: central players in the frank-starling mechanism of the heart.

    Science.gov (United States)

    Fukuda, Norio; Terui, Takako; Ohtsuki, Iwao; Ishiwata, Shin'ichi; Kurihara, Satoshi

    2009-05-01

    The basis of the Frank-Starling mechanism of the heart is the intrinsic ability of cardiac muscle to produce greater active force in response to stretch, a phenomenon known as length-dependent activation. A feedback mechanism transmitted from cross-bridge formation to troponin C to enhance Ca(2+) binding has long been proposed to account for length-dependent activation. However, recent advances in muscle physiology research technologies have enabled the identification of other factors involved in length-dependent activation. The striated muscle sarcomere contains a third filament system composed of the giant elastic protein titin, which is responsible for most passive stiffness in the physiological sarcomere length range. Recent studies have revealed a significant coupling of active and passive forces in cardiac muscle, where titin-based passive force promotes cross-bridge recruitment, resulting in greater active force production in response to stretch. More currently, the focus has been placed on the troponin-based "on-off" switching of the thin filament state in the regulation of length-dependent activation. In this review, we discuss how myocardial length-dependent activation is coordinately regulated by sarcomere proteins.

  17. Advances in cardiovascular fluid mechanics: bench to bedside.

    Science.gov (United States)

    Dasi, Lakshmi P; Sucosky, Philippe; de Zelicourt, Diane; Sundareswaran, Kartik; Jimenez, Jorge; Yoganathan, Ajit P

    2009-04-01

    This paper presents recent advances in cardiovascular fluid mechanics that define the current state of the art. These studies include complex multimodal investigations with advanced measurement and simulation techniques. We first discuss the complex flows within the total cavopulmonary connection in Fontan patients. We emphasize the quantification of energy losses by studying the importance of caval offsets as well as the differences among various Fontan surgical protocols. In our studies of the fluid mechanics of prosthetic heart valves, we reveal for the first time the full three-dimensional complexity of flow fields in the vicinity of bileaflet and trileaflet valves and the microscopic hinge flow dynamics. We also present results of these valves functioning in a patient-specific native aorta geometry. Our in vitro mitral valve studies show the complex mechanism of the native mitral valve apparatus. We demonstrate that the different components of the mitral valve have independent and synergistically complex functions that allow the valve to operate efficiently. We also show how valve mechanics change under pathological and repair conditions associated with enlarged ventricles. Finally, our ex vivo studies on the interactions between the aortic valve and its surrounding hemodynamic environment are aimed at providing insights into normal valve function and valve pathology. We describe the development of organ- and tissue-culture systems and the biological response of the tissue subjected to their respective simulated mechanical environment. The studies noted above have enhanced our understanding of the complex fluid mechanics associated with the cardiovascular system and have led to new translational technologies.

  18. Physiologic benefits of pulsatile perfusion during mechanical circulatory support for the treatment of acute and chronic heart failure in adults.

    Science.gov (United States)

    Guan, Yulong; Karkhanis, Tushar; Wang, Shigang; Rider, Alan; Koenig, Steven C; Slaughter, Mark S; El Banayosy, Aly; Undar, Akif

    2010-07-01

    A growing population experiencing heart failure (100,000 patients/year), combined with a shortage of donor organs (less than 2200 hearts/year), has led to increased and expanded use of mechanical circulatory support (MCS) devices. MCS devices have successfully improved clinical outcomes, which are comparable with heart transplantation and result in better 1-year survival than optimal medical management therapies. The quality of perfusion provided during MCS therapy may play an important role in patient outcomes. Despite demonstrated physiologic benefits of pulsatile perfusion, continued use or development of pulsatile MCS devices has been widely abandoned in favor of continuous flow pumps owing to the large size and adverse risks events in the former class, which pose issues of thrombogenic surfaces, percutaneous lead infection, and durability. Next-generation MCS device development should ideally implement designs that offer the benefits of rotary pump technology while providing the physiologic benefits of pulsatile end-organ perfusion.

  19. Biomedical engineering support. Progress report, August 15, 1976--May 15, 1977. [Testing of radioisotope-powered mechanical heart in calves

    Energy Technology Data Exchange (ETDEWEB)

    Kolff, W.J.; Olsen, D.B.

    1977-05-01

    A total of 41 ERDA Artificial Hearts have been implanted since the initiation of the ERDA Artificial Heart Program. During the period covered by this report, August 15, 1976 to May 15, 1977, 8 total heart replacement experiments have been performed in calves using the ERDA Blood Pump powered by an electric motor implanted in the abdomen. The average survival time for these 8 experiments was 162 hours (6.8 days). Significant advances have been achieved in the mechanical, surgical, and physiological areas. This year the oil-filled blood pump called the Implantable Version of the Bench Model (IVBM) was delivered by Westinghouse for in vivo studies at the University of Utah. Experience is being gained in the assembling and surgical implantation of this device. Several of these systems have been implanted and a 37 day survivor has been achieved.

  20. Vitamin D Biology in Heart Failure : Molecular Mechanisms and Systematic Review

    NARCIS (Netherlands)

    Meems, Laura M. G.; van der Harst, P.; van Gilst, W. H.; de Boer, R. A.

    2011-01-01

    Vitamin D has recently been suggested as an important mediator of blood pressure and cardiovascular disease, including heart failure. In patients with heart failure, low vitamin D levels are associated with adverse outcome and correlate with established clinical correlates and biomarkers. Many precu

  1. Estimation of viscous dissipative stresses induced by a mechanical heart valve using PIV data.

    Science.gov (United States)

    Li, Chi-Pei; Lo, Chi-Wen; Lu, Po-Chien

    2010-03-01

    Among the clinical complications of mechanical heart valves (MHVs), hemolysis was previously thought to result from Reynolds stresses in turbulent flows. A more recent hypothesis suggests viscous dissipative stresses at spatial scales similar in size to red blood cells may be related to hemolysis in MHVs, but the resolution of current instrumentation is insufficient to measure the smallest eddy sizes. We studied the St. Jude Medical (SJM) 27 mm valve in the aortic position of a pulsatile circulatory mock loop under physiologic conditions with particle image velocimetry (PIV). Assuming a dynamic equilibrium assumption between the resolved and sub-grid-scale (SGS) energy flux, the SGS energy flux was calculated from the strain rate tensor computed from the resolved velocity fields and the SGS stress was determined by the Smagorinsky model, from which the turbulence dissipation rate and then the viscous dissipative stresses were estimated. Our results showed Reynolds stresses up to 80 N/m2 throughout the cardiac cycle, and viscous dissipative stresses below 12 N/m2. The viscous dissipative stresses remain far below the threshold of red blood cell hemolysis, but could potentially damage platelets, implying the need for further study in the phenomenon of MHV hemolytic complications.

  2. Transient pressure at closing of a monoleaflet mechanical heart valve prosthesis: mounting compliance effect.

    Science.gov (United States)

    Wu, Z J; Gao, B Z; Hwang, N H

    1995-09-01

    An in vitro experimental study was performed to investigate the mounting compliance effect on the occluder closing dynamics and the transient pressure at the closing of the mitral Medtronic Hall (MH) mechanical heart valve (MHV). The closing velocity and the transient pressure were simultaneously measured at heart rates of 70, 90, 120, and 140 beats/minute with cardiac outputs of 5.0, 6.0, 7.5, and 8.5 liters/minute, respectively. The experiment was conducted under simulated physiologic ventricular and aortic pressures in a pulsatile mock flow loop. The characteristics of the transient pressure were investigated by detailed mapping of the transient pressure field in the atrial chamber using high frequency pressure transducers. Simultaneous measurements of the occluder closing velocity and the transient pressure around the seat stop of the MH showed that the transient pressure generated on the inflow side dropped below the vapor pressure of liquid during the occluder's sudden deceleration at closing. The amplitude of the transient pressure reduction (TR) was proportional to the occluder approaching velocity. The development of the transient pressure in the rigid and flexible mountings were significantly different. In the rigid mounting (RM), the pressure was reduced below the liquid's vapor pressure and maintained below -350 mmHg for approximately 180 microseconds. Strong signals of high frequency pressure oscillations (HPO) were recorded in the transient pressure traces. The timing of the HPO was found to be consistent with that of the cavitation bubble collapse as observed by others. In the flexible mounting (FM), TR also occurred, but recovered quickly and was followed immediately by a positive pressure spike. Relatively weak HPO appeared in the transient pressure trace. The mapping of the transient pressure field showed that both the transient pressure reduction (on the major orifice side) or rise (on the minor orifice side) as well as the HPO were locally

  3. The failing human heart is unable to use the Frank-Starling mechanism.

    Science.gov (United States)

    Schwinger, R H; Böhm, M; Koch, A; Schmidt, U; Morano, I; Eissner, H J; Uberfuhr, P; Reichart, B; Erdmann, E

    1994-05-01

    There is evidence that the failing human left ventricle in vivo subjected to additional preload is unable to use the Frank-Starling mechanism. The present study compared the force-tension relation in human nonfailing and terminally failing (heart transplants required because of dilated cardiomyopathy) myocardium. Isometric force of contraction of electrically driven left ventricular papillary muscle strips was studied under various preload conditions (2 to 20 mN). To investigate the influence of inotropic stimulation, the force-tension relation was studied in the presence of the cardiac glycoside ouabain. In skinned-fiber preparations of the left ventricle, developed tension was measured after stretching the preparations to 150% of the resting length. To evaluate the length-dependent activation of cardiac myofibrils by Ca2+ in failing and nonfailing myocardium, the tension-Ca2+ relations were also measured. After an increase of preload, the force of contraction gradually increased in nonfailing myocardium but was unchanged in failing myocardium. There were no differences in resting tension, muscle length, or cross-sectional area of the muscles between both groups. Pretreatment with ouabain (0.02 mumol/L) restored the force-tension relation in failing myocardium and preserved the force-tension relation in nonfailing tissue. In skinned-fiber preparations of the same hearts, developed tension increased significantly after stretching only in preparations from nonfailing but not from failing myocardium. The Ca2+ sensitivity of skinned fibers was significantly higher in failing myocardium (EC50, 1.0; 95% confidence limit, 0.88 to 1.21 mumol/L) compared with nonfailing myocardium (EC50, 1.7; 95% confidence limit, 1.55 to 1.86 mumol/L). After increasing the fiber length by stretching, a significant increase in the sensitivity of the myofibrils to Ca2+ was observed in nonfailing but not in failing myocardium. These experiments provide evidence for an impaired force

  4. On-X Heart Valve Prosthesis: Numerical Simulation of Hemodynamic Performance in Accelerating Systole.

    Science.gov (United States)

    Mirkhani, Nima; Davoudi, Mohammad Reza; Hanafizadeh, Pedram; Javidi, Daryoosh; Saffarian, Niloofar

    2016-09-01

    Numerical simulation of the bileaflet mechanical heart valves (BMHVs) has been of interest for many researchers due to its capability of predicting hemodynamic performance. A lot of studies have tried to simulate this three-dimensional complex flow in order to analyze the effect of different valve designs on the blood flow pattern. However, simplified models and prescribed motion for the leaflets were utilized. In this paper, transient complex blood flow in the location of ascending aorta has been investigated in a realistic model by fully coupled simulation. Geometry model for the aorta and the replaced valve is constructed based on the medical images and extracted point clouds. A 23-mm On-X Medical BMHV as the new generation design has been selected for the flow field analysis. The two-way coupling simulation is conducted throughout the accelerating phase in order to obtain valve dynamics in the opening process. The complex flow field in the hinge recess is captured precisely for all leaflet positions and recirculating zones and elevated shear stress areas have been observed. Results indicate that On-X valve yields relatively less transvalvular pressure gradient which would lower cardiac external work. Furthermore, converging inlet leads to a more uniform flow and consequently less turbulent eddies. However, the leaflets cannot open fully due to middle diffuser-shaped orifice. In addition, asymmetric butterfly-shaped hinge design and converging orifice leads to better hemodynamic performance. With the help of two-way fluid solid interaction simulation, leaflet angle follows the experimental trends more precisely rather than the prescribed motion in previous 3D simulations.

  5. Late sodium current: A mechanism for angina, heart failure, and arrhythmia.

    Science.gov (United States)

    Makielski, Jonathan C

    2016-02-01

    The peak sodium current underlies excitability and conduction in heart muscle, but a late sodium current flowing after the peak contributes to maintaining and prolonging the action potential plateau, and also to intracellular sodium loading, which in turn increases intracellular calcium with consequent effects on arrhythmia and diastolic function. Late sodium current is pathologically increased in both genetic and acquired heart disease, making it an attractive target for therapy to treat arrhythmia, heart failure, and angina. This review provides an overview of the underlying bases for the clinical implications of late sodium current block.

  6. Role of thrombus precursor protein in assessment of anticoagulation in patients with atrial fibrillation after mechanical heart valve replacement

    Institute of Scientific and Technical Information of China (English)

    秦川; 肖颖彬; 陈林; 王学锋; 钟前进

    2004-01-01

    Objective: To explore the role of thrombus precursor protein (TpP) in assessment of anticoagulation and predict the risk of thromboembolism in the patients with atrial fibrillation (AF) after mechanical heart valve replacement. Methods: TpP plasma concentration and international normalization ratio (INR) were measured in 45 patients with atrial fibrillation and 45 patients with sinus rhythm both after mechanical heart valve replacement. Twenty patients with non-valvular heart diseases were selected as the control. Furthermore, the patients with AF were divided into groups based on different TpP plasma concentration and TpP plasma concentration and INR were analyzed. Results: After mechanical heart valve replacement, those with AF had higher TpP plasma concentration than those with sinus rhythm. It was found that discordancy existed between INR and TpP plasma concentration in the patients with AF. There were 28 AF patients with TpP plasma concentration lower than 6 μg/ml and without bleeding, who might be at the optimal anticoagulant state. The 95% confidence of the mean INR value was 1.90-2.30 in these patients and TpP plasma concentration was between 2.84-5.74 μg/ml. Conclusion: Patients with AF might face higher risk of thromboembolism after mechanical valve replacement; INR between 1.90-2.30 and TpP plasma concentration between 2.84-6 μg/ml might be the optimal anticoagulant range for patients with AF after mechanical valve replacement.

  7. Sequential mechanical ventilation improves hemodynamics, cardiac function and neurohumoral status in elderly patients with acute left heart failure

    Institute of Scientific and Technical Information of China (English)

    Xing-Hong Zeng; Ming Chen; Qi Cao; Yan-Xia Chen

    2016-01-01

    Objective:To analyze the effect of sequential mechanical ventilation on improving hemodynamics, cardiac function and neurohumoral status in elderly patients with acute left heart failure.Methods:A total of 90 cases of elderly patients with acute left heart failure were randomly divided into observation group and control group, control group received conventional mechanical ventilation therapy, observation group received sequential mechanical ventilation, and then differences in hemodynamics, cardiac function and neurohumoral status were compared between two groups after treatment.Results:24 h after treatment, mPAP, PCWP and RAP levels of observation group after treatment were lower than those of control group, and CO level was higher than that of control group; LVEF value was higher than that of control group, and SVR, LVEDV and LVESV values were lower than those of control group; 12 h and 24 h after treatment, plasma Nt-proBNP, ANP, R, AngⅡ and ALD levels of observation group were significantly lower than those of control group.Conclusion:Sequential mechanical ventilation can optimize the illness in elderly patients with acute left heart failure, and plays a positive role in promoting patients' cardiac function recovery, restoring homeostasis and other aspects.

  8. Exertional dyspnoea in chronic heart failure: the role of the lung and respiratory mechanical factors

    OpenAIRE

    Bruno-Pierre Dubé; Piergiuseppe Agostoni; Pierantonio Laveneziana

    2016-01-01

    Exertional dyspnoea is among the dominant symptoms in patients with chronic heart failure and progresses relentlessly as the disease advances, leading to reduced ability to function and engage in activities of daily living. Effective management of this disabling symptom awaits a better understanding of its underlying physiology. Cardiovascular factors are believed to play a major role in dyspnoea in heart failure patients. However, despite pharmacological interventions, such as vasodilators o...

  9. Respiratory muscle training improves hemodynamics, autonomic function, baroreceptor sensitivity, and respiratory mechanics in rats with heart failure.

    Science.gov (United States)

    Jaenisch, Rodrigo B; Hentschke, Vítor S; Quagliotto, Edson; Cavinato, Paulo R; Schmeing, Letiane A; Xavier, Léder L; Dal Lago, Pedro

    2011-12-01

    Respiratory muscle training (RMT) improves functional capacity in chronic heart-failure (HF) patients, but the basis for this improvement remains unclear. We evaluate the effects of RMT on the hemodynamic and autonomic function, arterial baroreflex sensitivity (BRS), and respiratory mechanics in rats with HF. Rats were assigned to one of four groups: sedentary sham (n = 8), trained sham (n = 8), sedentary HF (n = 8), or trained HF (n = 8). Trained animals underwent a RMT protocol (30 min/day, 5 day/wk, 6 wk of breathing through a resistor), whereas sedentary animals did not. In HF rats, RMT had significant effects on several parameters. It reduced left ventricular (LV) end-diastolic pressure (P RMT (P RMT (P RMT (P RMT protocol in HF rats promotes an improvement in hemodynamic function, sympathetic and vagal heart modulation, arterial BRS, and respiratory mechanics, all of which are benefits associated with improvements in cardiopulmonary interaction.

  10. Numerical simulation of the non-Newtonian blood flow through a mechanical aortic valve. Non-Newtonian blood flow in the aortic root

    Science.gov (United States)

    De Vita, F.; de Tullio, M. D.; Verzicco, R.

    2016-04-01

    This work focuses on the comparison between Newtonian and non-Newtonian blood flows through a bileaflet mechanical heart valve in the aortic root. The blood, in fact, is a concentrated suspension of cells, mainly red blood cells, in a Newtonian matrix, the plasma, and consequently its overall behavior is that of a non-Newtonian fluid owing to the action of the cells' membrane on the fluid part. The common practice, however, assumes the blood in large vessels as a Newtonian fluid since the shear rate is generally high and the effective viscosity becomes independent of the former. In this paper, we show that this is not always the case even in the aorta, the largest artery of the systemic circulation, owing to the pulsatile and transitional nature of the flow. Unexpectedly, for most of the pulsating cycle and in a large part of the fluid volume, the shear rate is smaller than the threshold level for the blood to display a constant effective viscosity and its shear thinning character might affect the system dynamics. A direct inspection of the various flow features has shown that the valve dynamics, the transvalvular pressure drop and the large-scale features of the flow are very similar for the Newtonian and non-Newtonian fluid models. On the other hand, the mechanical damage of the red blood cells (hemolysis), induced by the altered stress values in the flow, is larger for the non-Newtonian fluid model than for the Newtonian one.

  11. Large-scale integrated model is useful for understanding heart mechanisms and developments of medical therapy.

    Science.gov (United States)

    Washio, Takumi; Okada, Jun-ichi; Sugiura, Seiryo; Hisada, Toshiaki

    2009-01-01

    In this paper, we discuss the need for a large-scale integrated computer heart model to understand cardiac pathophysiology and to assist in the development of novel treatments through our experiences with the "UT-heart" simulator. The UT-heart simulator is a multi-scale, multi-physics heart simulator that integrates and visualizes our knowledge of cardiac function in various aspects and scales. To demonstrate the usefulness of this model, we focus especially on two problems in cardiac anatomy and physiology. In the first application, the mechanistic implication of complex fiber and laminar structures is analyzed with respect to optimality of pumping performance. In the second application, the coronary circulation is analyzed, to identify factors that determine the behavior of the microcirculatory system. These two examples indicate not only the importance of the integration technique, but also the need to resolve structural complexities of the heart in the modeling. This leads naturally to incorporating high performance computing in medical therapy.

  12. INFLUENCE OF MIMIC CARDIAC RATE ON HYDRODYNAMICS OF DIFFERENT MECHANICAL PROSTHETIC CARDIAC VALVES IN VITRO

    Institute of Scientific and Technical Information of China (English)

    Yin-ping Chu; Jin-lian Cheng; Ru-kun Chen; Yu-bo Fan; Fang Pu

    2005-01-01

    Objective To assess the influence of mimic cardiac rate on hydrodynamics of different mechanical prosthetic cardiac valves.Methods US-made CarboMedics bileaflet valve, China-made Jiuling bileaflet valve and C-L tilting disc valve were tested via a pulsatile flow simulator in the aortic position. Testing conditions were set at mimic cardiac rates of 55 bpm, 75 bpm, 100bpm with a constant mimic cardiac output of 4 L/min. The mean pressure differences (△P), leakage volumes (LEV) and closing volumes (CLV) across each valve, and effective orifice areas (EOA) were analyzed.Results Within physiological range, △p, LEV, and CLV decreased as mimic cardiac rate increased, with a large extent of variance. EOA increased along with an increase in mimic cardiac rate. It was a different response in terms of cardiac rate alteration for different types of mechanical prosthetic cardiac valves.Conclusion Mimic cardiac rate change affects hydrodynamics of mechanical prosthetic cardiac valves. Within physiological range, the hydrodynamic of prosthetic bileaflet valve is better than that of tilting disc valve.

  13. Experimental investigations on the fluid-mechanics of an electrospun heart valve by means of particle image velocimetry.

    Science.gov (United States)

    Del Gaudio, Costantino; Gasbarroni, Pier Luca; Romano, Giovanni Paolo

    2016-12-01

    End-stage failing heart valves are currently replaced by mechanical or biological prostheses. Both types positively contribute to restore the physiological function of native valves, but a number of drawbacks limits the expected performances. In order to improve the outcome, tissue engineering can offer an alternative approach to design and fabricate innovative heart valves capable to support the requested function and to promote the formation of a novel, viable and correctly operating physiological structure. This potential result is particularly critical if referred to the aortic valve, being the one mainly exposed to structural and functional degeneration. In this regard, the here proposed study presents the fabrication and in vitro characterization of a bioresorbable electrospun heart valve prosthesis using the particle image velocimetry technique either in physiological and pathological fluid dynamic conditions. The scaffold was designed to reproduce the aortic valve geometry, also mimicking the fibrous structure of the natural extracellular matrix. To evaluate its performances for possible implantation, the flow fields downstream the valve were accurately investigated and compared. The experimental results showed a correct functionality of the device, supported by the formation of vortex structures at the edge of the three cusps, with Reynolds stress values below the threshold for the risk of hemolysis (which can be comprised in the range 400-4000N/m(2) depending on the exposure period), and a good structural resistance to the mechanical loads generated by the driving pressure difference.

  14. Anemia and iron deficiency in heart failure : mechanisms and therapeutic approaches

    NARCIS (Netherlands)

    van Veldhuisen, Dirk J.; Anker, Stefan D.; Ponikowski, Piotr; Macdougall, Iain C.

    2011-01-01

    Anemia and iron deficiency are common in patients with heart failure (HF), and are associated with worse symptoms and adverse outcomes in this population. Although the two can occur together, anemia in HF is often not caused by iron deficiency, and iron deficiency can be present without causing anem

  15. Age-Dependent Changes in Geometry, Tissue Composition and Mechanical Properties of Fetal to Adult Cryopreserved Human Heart Valves.

    Science.gov (United States)

    van Geemen, Daphne; Soares, Ana L F; Oomen, Pim J A; Driessen-Mol, Anita; Janssen-van den Broek, Marloes W J T; van den Bogaerdt, Antoon J; Bogers, Ad J J C; Goumans, Marie-José T H; Baaijens, Frank P T; Bouten, Carlijn V C

    2016-01-01

    There is limited information about age-specific structural and functional properties of human heart valves, while this information is key to the development and evaluation of living valve replacements for pediatric and adolescent patients. Here, we present an extended data set of structure-function properties of cryopreserved human pulmonary and aortic heart valves, providing age-specific information for living valve replacements. Tissue composition, morphology, mechanical properties, and maturation of leaflets from 16 pairs of structurally unaffected aortic and pulmonary valves of human donors (fetal-53 years) were analyzed. Interestingly, no major differences were observed between the aortic and pulmonary valves. Valve annulus and leaflet dimensions increase throughout life. The typical three-layered leaflet structure is present before birth, but becomes more distinct with age. After birth, cell numbers decrease rapidly, while remaining cells obtain a quiescent phenotype and reside in the ventricularis and spongiosa. With age and maturation-but more pronounced in aortic valves-the matrix shows an increasing amount of collagen and collagen cross-links and a reduction in glycosaminoglycans. These matrix changes correlate with increasing leaflet stiffness with age. Our data provide a new and comprehensive overview of the changes of structure-function properties of fetal to adult human semilunar heart valves that can be used to evaluate and optimize future therapies, such as tissue engineering of heart valves. Changing hemodynamic conditions with age can explain initial changes in matrix composition and consequent mechanical properties, but cannot explain the ongoing changes in valve dimensions and matrix composition at older age.

  16. Detection of acoustic cavitation in the heart with microbubble contrast agents in vivo: a mechanism for ultrasound-induced arrhythmias.

    Science.gov (United States)

    Rota, Claudio; Raeman, Carol H; Child, Sally Z; Dalecki, Diane

    2006-11-01

    Ultrasound fields can produce premature cardiac contractions under appropriate exposure conditions. The pressure threshold for ultrasound-induced premature contractions is significantly lowered when microbubble contrast agents are present in the vasculature. The objective of this study was to measure directly ultrasound-induced cavitation in the murine heart in vivo and correlate the occurrence of cavitation with the production of premature cardiac contractions. A passive cavitation detection technique was used to quantify cavitation activity in the heart. Experiments were performed with anesthetized, adult mice given intravenous injections of either a contrast agent (Optison) or saline. Murine hearts were exposed to ultrasound pulses (200 kHz, 1 ms, 0.1-0.25 MPa). Premature beats were produced in mice injected with Optison and the likelihood of producing a premature beat increased with increasing pressure amplitude. Similarly, cavitation was detected in mice injected with Optison and the amplitude of the passive cavitation detector signal increased with increasing exposure amplitude. Furthermore, there was a direct correlation between the extent of cavitation and the likelihood of ultrasound producing a premature beat. Neither premature beats nor cavitation activity were observed in animals injected with saline and exposed to ultrasound. These results are consistent with acoustic cavitation as a mechanism for this bioeffect.

  17. Neurohumoral Mechanisms Associated with Orthostasis: Reaffirmation of the Significant Contribution of the Heart Rate Response

    Science.gov (United States)

    2014-06-30

    rate (HR, left panel) and systolic blood pressure ( SBP , right panel) during supine pre-stand (open bars) and at 5 min of standing (solid bars) in...standing systolic blood pressure (Standing SBP ) in subjects who did or did not experience syncopal symptoms during a stand test following 30 days of bed...than 100 bpm, vagal withdrawal con- tributes to the elevation of heart rate (Mosqueda-Garcia, 1995). However, in the absence of vagally-mediated

  18. Mechanisms of the Frank-Starling phenomena studied in intact hearts.

    Science.gov (United States)

    Burkhoff, D; Stennett, R A; Ogino, K

    1995-01-01

    The impact of ventricular volume on the relationship between intracellular calcium and ventricular pressure under steady-state conditions was determined in intact ferret hearts. The results reveal major quantitative differences and minor qualitative differences between these relations and those previously measured in isolated intact and skinned cardiac muscle. The importance of these differences is discussed within the context of developing a comprehensive mechanistic theory to describe load-dependence of the intact ventricle.

  19. Evaluation of left ventricular mechanical dyssynchrony in chronic heart failure patients by two-dimensional speckle tracking imaging.

    Science.gov (United States)

    Jiang, Feng-Xia; Guo, Rui-Qiang; Chen, Jin-Ling

    2013-07-01

    The purpose of this study was to evaluate left ventricular mechanical dyssynchrony (LVMD) in chronic heart failure (CHF) patients using two-dimensional speckle tracking imaging (2D-STI), and also to compare the usefulness of three patterns of myocardial deformation in mechanical dyssynchrony assessment. Furthermore, the relationships between left ventricular ejection fraction (LVEF), QRS duration (QRSd), and LVMD were explored. In total, 78 patients and 60 healthy individuals (group 3) were enrolled. The patients were classified into two subgroups: LVEF≤35% (group 1), 35%0.05). CHF patients have different extents of LVMD. Longitudinal deformation shows the best detectability of dyssynchrony motion. Left ventricular systolic function was closely related to mechanical dyssynchrony, whereas QRSd showed no significant correlation.

  20. In Vitro Study of Influence of Mimic Cardiac Rate on Hydrodynamics of the Different Mechanical Cardiac Valve Prostheses

    Institute of Scientific and Technical Information of China (English)

    CHU Yin-ping; CHENG Jin-lian; CHEN Ru-kun; FAN Yu-bo; PU Fang

    2005-01-01

    Objective:To assess the influence of mimic cardiac rate on hydrodynamics of the different mechanical prosthetic cardiac valves. Methods: US-made CarboMedics bileaflet valve and China-made Jiuling bileaflet valve and C-L tilting disc valve have been tested in a pulsatile flow simulator in the aortic position. The testing condition was set at the mimic cardiac rate of 55 beats/min,75 beats/min,100beats/min and a constant mimic cardiac output of 4L/min. The mean pressure differences (△P) ,leakage volumes (LEV) and closing volumes (CLV) across each valve,and the effective orifice areas(EOA) have been analyzed. Results:Within the range of physiology,the △P,LEV and CLV were falling as the increasing of mimic cardiac rate,and the extent of variance was larger. The EOA was increasing with the increase of the mimic cardiac rate. It is a different response as the altering of the cardiac rate for the different type of the mechanical prosthetic cardiac valves.Conclusions:The change of the mimic cardiac rate can affect the hydrodynamics of the mechanical prosthetic cardiac valves. The hydrodynamics of the bileaflet valve prosthesis is better than the tilting disc valve.

  1. Metformin in patients with ischemic heart disease and type 2 diabetes mellitus: mechanism of action and clinical efficiency

    Directory of Open Access Journals (Sweden)

    E N Kravchuk

    2013-03-01

    Full Text Available Diabetes mellitus is one of the leading causes of death in modern society, primarily due to its cardiovascular complications. This factor drives search for novel pharmacologic agents to affect not only glycemic levels, but also the cardiovascular prognosis in diabetic patients with ischemic heart disease. Recent studies demonstrate that aside from basic blood glucose lowering action, metformin shows beneficial influence on blood rheology and vascular tone, hemostasis, oxidative stress, lipid spectrum and delivers and an ant-ischemic effect. Here we review clinical and experimental evidence on cardio- and vasoprotective effects of metformin, highlighting their molecular mechanisms.

  2. PERIPHERAL VENO-ARTERIAL ECMO AS MECHANICAL CIRCULATORY SUPPORT BEFORE HEART TRANSPLANTATION

    Directory of Open Access Journals (Sweden)

    E. A. Spirina

    2013-01-01

    Full Text Available Aim of our clinical study was evaluation own initial experience of high-urgency ortotopic heart transplantation (OHT in recipients, who were bridged on peripheral Vena-Arterial Extracorporeal Membrane Oxygenation (VA ECMO. Materials and methods. In this study was included 17 patients (14/3 M/F, age 16–66 (40.1 ± 4.2 yrs who underwent OHT while on peripheral ECMO support. In all cases we used peripheral surgical can- nulation technique via femoral vessels – arterial cannula 15–19 Fr, venous cannula – 21–25 Fr, arterial cannula or vascular catheter 8–10 Fr for anterograde leg’s perfusion. Results. Duration Vena-Arterial Extracorporeal Membrane Oxygenation before OHT was 81 ± 17 h. VA ECMO support was blood flow 4.8 ± 0.6 l/min or 2.63 ± 0/04 l/min/m2, gas flow 4.8 ± 0.6 l/min, FiO2 0.86 ± 0.07. Vena-Arterial Extracorporeal Membrane Oxygenation support was continued in “protective mode” (blood flow 1.9 ± 0.2 l/min 4.3 ± 0.5 days after OHT. Thirteen pa- tients (76.4% were weaned from VA ECMO successfully and survived to be discharged. ICU and hospital LOS after orthotopic heart transplantation was respectively 6.7 ± 0.8 and 32.3 ± 4.6 days in group of survived patients. The reasons of a lethal outcome (n = 4, 23.5% were sepsis and multiorgan failure (n = 3, sudden cardiac arrest (n = 1. Conclusion. Vena-Arterial Extracorporeal Membrane Oxygenation is a favorable short-term method of circulatory support in patients who needed in high-urgency heart transplantation. 

  3. Marine omega-3 highly unsaturated fatty acids: From mechanisms to clinical implications in heart failure and arrhythmias.

    Science.gov (United States)

    Glück, Tobias; Alter, Peter

    2016-07-01

    Therapeutic implications of marine omega-3 highly unsaturated fatty acids (HUFA) in cardiovascular disease are still discussed controversially. Several clinical trials report divergent findings and thus leave ambiguity on the meaning of oral omega-3 therapy. Potential prognostic indications of HUFA treatment have been predominantly studied in coronary artery disease, sudden cardiac death, ventricular arrhythmias, atrial fibrillation and heart failure of various origin. It is suspected that increased ventricular wall stress is crucially involved in the prognosis of heart failure. Increased wall stress and an unfavorable myocardial remodeling is associated with an increased risk of arrhythmias by stretch-activated membrane ion channels. Integration of HUFA into the microenvironment of cardiomyocyte ion channels lead to allosteric changes and increase the electrical stability. Increased ventricular wall stress appears to be involved in the local myocardial as well as in the hepatic fatty acid metabolism, i.e. a cardio-hepatic syndrome. Influences of an altered endogenous HUFA metabolism and an inverse shift of the fatty acid profile was underrated in the past. A better understanding of these interacting endogenous mechanisms appears to be required for interpreting the findings of recent experimental and clinical studies. The present article critically reviews major studies on basic pathophysiological mechanisms and treatment effects in clinical trials.

  4. Quantitative Mitochondrial Proteomics Study on Protective Mechanism of Grape Seed Proanthocyanidin Extracts Against Ischemia/Reperfusion Heart Injury in Rat

    Institute of Scientific and Technical Information of China (English)

    LU Wei-da; QIU Jie; ZHAO Gai-xia; QIE Liang-yi; WEI Xin-bing; GAO Hai-qing

    2012-01-01

    Cardiac ischemia/reperfusion(I/R) injury is a critical condition,often associated with high morbidity and mortality.The cardioprotective effect of grape seed proanthocyanidin extracts(GSPE) against oxidant injury during I/R has been described in previous studies.However,the underlying molecular mechanisms have not been fully elucidated.This study investigated the effect of GSPE on reperfusion arrhythmias especially ventricular tachycardia(VT)and ventricular fibrillation(VF),the lactic acid accumulation and the ultrastructure of ischemic cardiomyocytes as well as the global changes of mitochondria proteins in in vivo rat heart model against I/R injury.GSPE significantly reduced the incidence of VF and VT,lessened the lactic acid accumulation and attenuated the ultrastructure damage.Twenty differential proteins related to cardiac protection were revealed by isobaric tag for relative and absolute quantitation(iTRAQ) profiling.These proteins were mainly involved in energy metabolism.Besides,monoamine oxidase A(MAOA) was also identified.The differential expression of several proteins was validated by Western blot.Our study offered important information on the mechanism of GSPE treatment in ischemic heart disease.

  5. Can Pregnancy Harm Your Heart?

    Science.gov (United States)

    ... and women's heart health, said Dr. Mary Ann Bauman, a spokeswoman for the American Heart Association. "We ... of the mechanisms of women and heart disease," Bauman said. "Women aren't just men with ovaries. ...

  6. Neuregulin-1 preconditioning protects the heart against ischemia/reperfusion injury through a PI3K/Akt-dependent mechanism

    Institute of Scientific and Technical Information of China (English)

    FANG Shan-juan; WU Xue-si; HAN Zhi-hong; ZHANG Xiao-xia; WANG Chun-mei; LI Xin-yan; LU Ling-qiao; ZHANG Jing-lan

    2010-01-01

    Background Neuregulin-1 (NRG-1), the ligand of the myocardial ErbB receptor, is a protein mediator with regulatory actions in the heart. This study investigated whether NRG-1 preconditioning has protective effects on myocardial ischemia/reperfusion (I/R) injury and its potential mechanism.Methods We worked with an in vivo rat model with induced myocardial ischemia (45 minutes) followed by reperfusion (3 hours). NRG-1 message was detected in the heart using RT-PCR and the protein levels of NRG-1 and ErbB4 were detected by Western blotting analysis. Infarct size was assessed using the staining agent triphenyltetrazolium chloride and cardiac function was continuously monitored. The levels of creatine kinase and lactate dehydrogenase in plasma were analyzed to assess the degree of cardiac injury. The extent of cardiac apoptosis was evaluated by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay and by Western blotting analysis of cleaved caspase-3. We examined the phosphorylation of Akt in the myocardium and the effect of PI3K/Akt inhibition on NRG-1-induced cardioprotection.Results Transcription and expression of NRG-1 and phosphorylation of its ErbB4 receptor were significantly upregulated in the I/R hearts. NRG-1 pretreatment reduced the infarct size following cardiac I/R in a concentration-dependent manner with an optimal concentration of 4 μg/kg in vivo. NRG-1 pretreatment with 4 μg/kg, i.v.markedly reduced the plasma creatine kinase and lactate dehydrogenase levels. Pretreatment with NRG-1 also significantly reduced the percentage of TUNEL positive myocytes and the level of cleaved caspase-3 in the I/R hearts.Pretreatment with NRG-1 significantly increased phosphorylation of Akt following I/R. Furthermore, the cardioprotective effect limiting the infarct size that was induced by NRG-1 was abolished by co-administration of the PI3K inhibitor LY294002.Conclusions The concentration of NRG-1, a new autacoid, was rapidly upregulated

  7. The Effects and Mechanism of Atorvastatin on Pulmonary Hypertension Due to Left Heart Disease.

    Directory of Open Access Journals (Sweden)

    Qing Wang

    Full Text Available Pulmonary hypertension due to left heart disease (PH-LHD is one of the most common forms of PH, termed group 2 PH. Atorvastatin exerts beneficial effects on the structural remodeling of the lung in ischemic heart failure. However, few studies have investigated the effects of atorvastatin on PH due to left heart failure induced by overload.Group 2 PH was induced in animals by aortic banding. Rats (n = 20 were randomly divided into four groups: a control group (C, an aortic banding group (AOB63, an atorvastatin prevention group (AOB63/ATOR63 and an atorvastatin reversal group (AOB63/ATOR50-63. Atorvastatin was administered for 63 days after banding to the rats in the AOB63/ATOR63 group and from days 50 to 63 to the rats in the AOB63/ATOR50-63 group.Compared with the controls, significant increases in the mean pulmonary arterial pressure, pulmonary arteriolar medial thickening, biventricular cardiac hypertrophy, wet and dry weights of the right middle lung, percentage of PCNA-positive vascular smooth muscle cells, inflammatory infiltration and expression of RhoA and Rho-kinase II were observed in the AOB63 group, and these changes concomitant with significant decreases in the percentage of TUNEL-positive vascular smooth muscle cells. Treatment of the rats in the AOB63/ATOR63 group with atorvastatin at a dose of 10 mg/kg/day significantly decreased the mean pulmonary arterial pressure, right ventricular hypertrophy, pulmonary arteriolar medial thickness, inflammatory infiltration, percentage of PCNA-positive cells and pulmonary expression of RhoA and Rho-kinase II and significantly augmented the percentage of TUNEL-positive cells compared with the AOB63 group. However, only a trend of improvement in pulmonary vascular remodeling was detected in the AOB63/ATOR50-63 group.Atorvastatin prevents pulmonary vascular remodeling in the PH-LHD model by down-regulating the expression of RhoA/Rho kinase, by inhibiting the proliferation and increasing the

  8. [Possible mechanism of production of the musical second heart sound and its clinical significance].

    Science.gov (United States)

    Fukuda, N; Hosoi, K; Iuchi, A; Ogawa, S; Kageji, Y; Hayashi, M; Yoshimoto, K; Tanimoto, M; Oki, T

    1991-01-01

    To investigate the predisposing factors and the clinical significance of the musical aortic component of the second heart sound (musical S2), 18 patients with musical S2 (musical group) among the consecutive 2,000 patients with phonocardiographic examination were noninvasively studied by analyzing underlying diseases, phonocardiographic findings, organic changes of the aortic valve, severity of aortic regurgitation and left ventricular dysfunction. Organic changes of the aortic valve were assessed by two-dimensional echocardiography, and aortic regurgitation was assessed by color Doppler flow imaging. Twenty-two normal subjects (normal group) and 17 patients with essential hypertension (hypertensive group) served as controls. Mean ages were matched among the three groups. 1. Left ventricular dilatation (seven patients) and hypertension (six patients) were the dominant part of underlying disease in the musical group. 2. Musical S2 was classified in the following two types based on the phonocardiographic characteristics; musical vibrations followed immediately after the accentuated S2, and the S2 which was replaced by regular vibratory waves. 3. Frequency of the musical vibrations ranged from 120 to 200 Hz, and its duration ranged from 60 to 120 msec. Amplitude of the musical vibrations decreased by inhalation of amyl nitrite, but increased by infusion of methoxamine. In a case with mild rheumatic valve disease, methoxamine induced marked intensification of the amplitude and prolongation of the duration of the musical vibrations, finally giving a typical cooing murmur. 4. Echo intensity of the aortic valve tended to be higher in the musical group than in the other two groups. 5. Echocardiographically, aortic regurgitation appeared more frequently in the musical group (88%) than in the normal (36%) and hypertensive (41%) groups. Area of the aortic regurgitant signal was significantly larger in the musical group (4.1 +/- 1.4 cm2) than in the normal (1.2 +/- 0.8 cm2

  9. Effects of simulated microgravity on circadian rhythm of caudal arterial pressure and heart rate in rats and their underlying mechanism

    Directory of Open Access Journals (Sweden)

    Li CHEN

    2016-04-01

    Full Text Available Objective  To explore the effects of simulated microgravity on the circadian rhythm of rats' caudal arterial pressure and heart rate, and their underlying mechanism. Methods  Eighteen male SD rats (aged 8 weeks were randomly assigned to control (CON and tail suspension (SUS group (9 each. Rats with tail suspension for 28 days were adopted as the animal model to simulate microgravity. Caudal arterial pressure and heart rate of rats were measured every 3 hours. The circadian difference of abdominal aorta contraction was measured by aortic ring test. Western blotting was performed to determine and compare the protein expression level of clock genes such as Per2 (Period2, Bmal1 (Aryl hydrocarbon receptor nuclear translocatorlike and dbp (D element binding protein in suprachiasmatic nucleus (SCN and abdominal aorta of rats in CON and SUS group at different time points. Results  Compared with CON group, the caudal arterial pressure, both systolic and diastolic pressure, decreased significantly and the diurnal variability disappeared, meanwhile the heart rate increased obviously and also the diurnal variability disappeared in rats of SUS group. Compared with CON group, the contraction reactivity of abdominal aorta decreased with disappearence of the diurnal variability, and also the clock genes expression in SCN and abdominal aorta showed no diurnal variability in rats of SUS group. Conclusion  Simulated microgravity may lead to circadian rhythm disorders in rats' cardiovascular system, which may be associated with the changes of the clock genes expression. DOI: 10.11855/j.issn.0577-7402.2016.04.06

  10. Phentolamine prevents the adverse effects of adenosine on glycolysis and mechanical function in isolated working rat hearts subjected to antecedent ischemia.

    Science.gov (United States)

    Finegan, B A; Gandhi, M; Clanachan, A S

    2000-06-01

    adenosine from inhibition to stimulation of glycolysis or alter the cardioprotective properties of adenosine in hearts subject to ischemia and reperfusion. The detrimental switch in the metabolic and cardioprotective effects of adenosine, in hearts subject to AIS, can be prevented by phentolamine, an alpha-adrenoceptor antagonist. These data support the concept that modulation of glucose metabolism is an important factor in the mechanical functional recovery of the post-ischemic heart.

  11. Skeletal myoblasts for heart regeneration and repair: state of the art and perspectives on the mechanisms for functional cardiac benefits.

    Science.gov (United States)

    Formigli, L; Zecchi-Orlandini, S; Meacci, E; Bani, D

    2010-01-01

    Until recently, skeletal myoblasts (SkMBs) have been the most widely used cells in basic research and clinical trials of cell based therapy for cardiac repair and regeneration. Although SkMB engraftment into the post-infarcted heart has been consistently found to improve cardiac contractile function, the underlying therapeutic mechanisms remain still a matter of controversy and debate. This is basically because SkMBs do not attain a cardiac-like phenotype once homed into the diseased heart nor they form a contractile tissue functionally coupled with the surrounding viable myocardium. This issue of concern has generated the idea that the cardiotropic action of SkMBs may depend on the release of paracrine factors. However, the paracrine hypothesis still remains ill-defined, particularly concerning the identification of the whole spectrum of cell-derived soluble factors and details on their cardiac effects. In this context, the possibility to genetically engineering SkMBs to potentate their paracrine attitudes appears particularly attractive and is actually raising great expectation. Aim of the present review is not to cover all the aspects of cell-based therapy with SkMBs, as this has been the object of previous exhaustive reviews in this field. Rather, we focused on novel aspects underlying the interactions between SkMBs and the host cardiac tissues which may be relevant for directing the future basic and applied research on SkMB transplantation for post ischemic cardiac dysfunction.

  12. Heart Rate Changes in Response to Mechanical Pressure Stimulation of Skeletal Muscles Are Mediated by Cardiac Sympathetic Nerve Activity

    Science.gov (United States)

    Watanabe, Nobuhiro; Hotta, Harumi

    2017-01-01

    Stimulation of mechanoreceptors in skeletal muscles such as contraction and stretch elicits reflexive autonomic nervous system changes which impact cardiovascular control. There are pressure-sensitive mechanoreceptors in skeletal muscles. Mechanical pressure stimulation of skeletal muscles can induce reflex changes in heart rate (HR) and blood pressure, although the neural mechanisms underlying this effect are unclear. We examined the contribution of cardiac autonomic nerves to HR responses induced by mechanical pressure stimulation (30 s, ~10 N/cm2) of calf muscles in isoflurane-anesthetized rats. Animals were artificially ventilated and kept warm using a heating pad and lamp, and respiration and core body temperature were maintained within physiological ranges. Mechanical stimulation was applied using a stimulation probe 6 mm in diameter with a flat surface. Cardiac sympathetic and vagus nerves were blocked to test the contribution of the autonomic nerves. For sympathetic nerve block, bilateral stellate ganglia, and cervical sympathetic nerves were surgically sectioned, and for vagus nerve block, the nerve was bilaterally severed. In addition, mass discharges of cardiac sympathetic efferent nerve were electrophysiologically recorded. Mechanical stimulation increased or decreased HR in autonomic nerve-intact rats (range: −56 to +10 bpm), and the responses were negatively correlated with pre-stimulus HR (r = −0.65, p = 0.001). Stimulation-induced HR responses were markedly attenuated by blocking the cardiac sympathetic nerve (range: −9 to +3 bpm, p mechanical stimulation increased, or decreased the frequency of sympathetic nerve activity in parallel with HR (r = 0.77, p = 0.0004). Furthermore, the changes in sympathetic nerve activity were negatively correlated with its tonic level (r = −0.62, p = 0.0066). These results suggest that cardiac sympathetic nerve activity regulates HR responses to muscle mechanical pressure stimulation and the direction of HR

  13. Mitochondrial damage: An important mechanism of ambient PM{sub 2.5} exposure-induced acute heart injury in rats

    Energy Technology Data Exchange (ETDEWEB)

    Li, Ruijin; Kou, Xiaojing; Geng, Hong; Xie, Jingfang; Tian, Jingjing [Institute of Environmental Science, College of Environmental & Resource Sciences, Shanxi University, Taiyuan (China); Cai, Zongwei, E-mail: zwcai@hkbu.edu.hk [State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong SAR (China); Dong, Chuan, E-mail: dc@sxu.edu.cn [Institute of Environmental Science, College of Environmental & Resource Sciences, Shanxi University, Taiyuan (China)

    2015-04-28

    Highlights: • PM{sub 2.5} induces heart mitochondrial morphological damage of rats. • Mitochondrial fission/fusion gene expression is important regulation mechanism. • Proinflammatoy cytokine level changes are accompanied with mitochondrial damage. • Alterations in oxidative stress and calcium homeostasis are focused on. - Abstract: Epidemiological studies suggested that ambient fine particulate matter (PM{sub 2.5}) exposure was associated with cardiovascular disease. However, the underlying mechanism, especially the mitochondrial damage mechanism, of PM{sub 2.5}-induced heart acute injury is still unclear. In this study, the alterations of mitochondrial morphology and mitochondrial fission/fusion gene expression, oxidative stress, calcium homeostasis and inflammation in hearts of rats exposed to PM{sub 2.5} with different dosages (0.375, 1.5, 6.0 and 24.0 mg/kg body weight) were investigated. The results indicated that the PM{sub 2.5} exposure induced pathological changes and ultra-structural damage in hearts such as mitochondrial swell and cristae disorder. Furthermore, PM{sub 2.5} exposure significantly increased specific mitochondrial fission/fusion gene (Fis1, Mfn1, Mfn2, Drp1 and OPA1) expression in rat hearts. These changes were accompanied by decreases of activities of superoxide dismutase (SOD), Na{sup +}K{sup +}-ATPase and Ca{sup 2+}-ATPase and increases of levels of malondialdehyde (MDA), inducible nitric oxide synthase (iNOS) and nitric oxide (NO) as well as levels of pro-inflammatory mediators including TNF-α, IL-6 and IL-1β in rat hearts. The results implicate that mitochondrial damage, oxidative stress, cellular homeostasis imbalance and inflammation are potentially important mechanisms for the PM{sub 2.5}-induced heart injury, and may have relations with cardiovascular disease.

  14. Biomedical engineering support. Annual progress report, August 15, 1974--August 14, 1975. [/sup 238/PuO/sub 2/-powered mechanical heart

    Energy Technology Data Exchange (ETDEWEB)

    Kolff, W.J.; Smith, L.M.; Sandquist, G.M.

    1975-01-01

    The major responsibility of the Institute for Biomedical Engineering at the University of Utah under the ERDA Artificial Heart Program has been to provide in vitro and in vivo experimental data and evaluation of the anatomical fitting, accommodation, performance and adequacy of the artificial heart system and its components as they are developed in the ERDA Program and provided to the Institute for study. The Institute also has the responsibility of designing, constructing and testing the blood handling components of the Blood Pump and insuring reliability, durability and satisfactory performance of these system components. During the reporting period, nine total heart replacement experiments were performed in calves using the ERDA Blood Pump powered by an electric motor implanted in the abdomen. Results of the experiments are given. Ultimately the mechanical heart will be powered by a radioisotope heat source. (TFD)

  15. Anemia and iron deficiency in heart failure: mechanisms and therapeutic approaches.

    Science.gov (United States)

    van Veldhuisen, Dirk J; Anker, Stefan D; Ponikowski, Piotr; Macdougall, Iain C

    2011-05-31

    Anemia and iron deficiency are common in patients with heart failure (HF), and are associated with worse symptoms and adverse outcomes in this population. Although the two can occur together, anemia in HF is often not caused by iron deficiency, and iron deficiency can be present without causing anemia. Erythropoiesis-stimulating agents have been investigated extensively in the past few years and might be of benefit in patients with HF and anemia. However, concerns have arisen regarding the safety of erythropoiesis-stimulating agents in patients with chronic kidney disease and so the results of a large mortality trial are eagerly awaited to provide information on safety in patients with HF. Iron supplementation or replacement is a much older treatment option for patients with HF and anemia, but questions about the safety of intravenous iron, and absorption problems with oral formulations have prevented its widespread use to date. In the past few years, however, new data on the importance of iron deficiency in HF have become available, and a number of studies with intravenous iron have shown promising results. Therefore, this treatment approach is likely to become an attractive option for patients with HF and iron deficiency, both with and without anemia.

  16. Pyruvate dehydrogenase kinase regulatory mechanisms and inhibition in treating diabetes, heart ischemia, and cancer.

    Science.gov (United States)

    Roche, T E; Hiromasa, Y

    2007-04-01

    The fraction of pyruvate dehydrogenase complex (PDC) in the active form is reduced by the activities of dedicated PD kinase isozymes (PDK1, PDK2, PDK3 and PDK4). Via binding to the inner lipoyl domain (L2) of the dihydrolipoyl acetyltransferase (E2 60mer), PDK rapidly access their E2-bound PD substrate. The E2-enhanced activity of the widely distributed PDK2 is limited by dissociation of ADP from its C-terminal catalytic domain, and this is further slowed by pyruvate binding to the N-terminal regulatory (R) domain. Via the reverse of the PDC reaction, NADH and acetyl-CoA reductively acetylate lipoyl group of L2, which binds to the R domain and stimulates PDK2 activity by speeding up ADP dissociation. Activation of PDC by synthetic PDK inhibitors binding at the pyruvate or lipoyl binding sites decreased damage during heart ischemia and lowered blood glucose in insulin-resistant animals. PDC activation also triggers apoptosis in cancer cells that selectively convert glucose to lactate.

  17. Heart Health - Brave Heart

    Science.gov (United States)

    ... Robert's (left) three heart attacks, he and his wife Sue began volunteering for The Mended Hearts, a ... arrest. "It scared the heck out of my wife," Robert remembers. He was operated on and doctors ...

  18. [Clinical experience of mechanical ventricular support with centrifugal pump for severe ventricular failure after open heart surgery].

    Science.gov (United States)

    Matsuwaka, R; Matsuda, H; Kaneko, M; Masai, T; Fudemoto, Y; Kobayashi, T; Imagawa, H; Miyamoto, K; Morisaki, H; Kawashima, Y

    1990-09-01

    Five adult patients (pts) with age 15-67 (mean 43) received mechanical circulatory support with centrifugal pump (Biomedicus, BP-80, Sarns centrifugal pump) for postcardiotomy profound shock. Three pts underwent left ventricular support (LVS) alone, and the other 2 required biventricular support (BVS). Duration of the LVS ranged from 33 to 240 hours (mean 126 hours) and the right ventricular support 92, 120 hrs. Pump flow rate was 1.1 to 2.5 (mean 1.9) L/min/m2. Sixteen pumps were used and the pump exchange was performed 9 times in five pts and an average perfusion time per pump was 57 hrs. Two of 3 pts with LVS alone survived and one died of multiorgan failure associated with right heart dysfunction. In two pts with BVS, one survived and the other died of persistent low cardiac output early after pump removal. As the complication during mechanical support, bleeding was seen in 3 pts and cerebral infarction in one. Although centrifugal pump has potential limitation in antithrombogenicity and durability, this device provides a simple and effective mechanical circulatory support.

  19. Anticoagulation in pregnant women with mechanical heart valves : the new ESC guidelines

    NARCIS (Netherlands)

    Pieper, P. G.

    2012-01-01

    In pregnant women with a mechanical valve prosthesis, anticoagulation therapy is challenging because of the risk of embryopathy with vitamin K antagonists (VKA's), while unfractioned heparin and low molecular weight heparin (LMWH) are associated with a higher risk of valve thrombosis [1]. The presen

  20. Central autonomic control of the heart, angina, and pathogenic mechanisms of post-myocardial infarction depression

    NARCIS (Netherlands)

    Ter Horst, GJ

    1999-01-01

    Depression can develop in 20% of the patients with a myocardial infarction (MI). Pathobiological mechanisms underlying the development of mood disorders in these patients are unknown. Since post-MI depression has been associated with increased risk of mortality we hypothesized that dysfunction of li

  1. Protective effect of acupuncture on heart in mice with hyperlipemia and its mechanism

    Institute of Scientific and Technical Information of China (English)

    申洪波

    2014-01-01

    Objective To observe the inhibiting effect of acupuncture on blood lipid,myocardial hypertrophy and fibrosis in mice with hyperlipemia,and explore its possible action mechanism.Methods Ten inbred mice(C57)were applied.Forty ApoE(-/-)mice removed gene of apolipoprotein E were randomly divided into a control

  2. Acute cardiac arrhythmias following surgery for congenital heart disease: mechanisms, diagnostic tools, and management.

    Science.gov (United States)

    Payne, Linda; Zeigler, Vicki L; Gillette, Paul C

    2011-06-01

    This article focuses on the management of those cardiac arrhythmias most commonly seen in the immediate postoperative period. They include ventricular tachycardia, ventricular fibrillation, atrial flutter, junctional ectopic tachycardia, bradycardia, and atrioventricular block. The mechanisms of cardiac arrhythmias are reviewed followed by a brief overview of the predominant acute arrhythmias, tools used for the diagnostic evaluation of these arrhythmias, management strategies, and, finally, nursing considerations.

  3. Hemolymph circulation in insect sensory appendages: functional mechanics of antennal accessory pulsatile organs (auxiliary hearts) in the mosquito Anopheles gambiae.

    Science.gov (United States)

    Boppana, Sushma; Hillyer, Julián F

    2014-09-01

    Mosquito antennae provide sensory input that modulates host-seeking, mating and oviposition behaviors. Thus, mosquitoes must ensure the efficient transport of molecules into and out of these appendages. To accomplish this, mosquitoes and other insects have evolved antennal accessory pulsatile organs (APOs) that drive hemolymph into the antennal space. This study characterizes the structural mechanics of hemolymph propulsion throughout the antennae of Anopheles gambiae. Using intravital video imaging, we show that mosquitoes possess paired antennal APOs that are located on each side of the head's dorsal midline. They are situated between the frons and the vertex in an area that is dorsal to the antenna but ventral to the medial-most region of the compound eyes. Antennal APOs contract in synchrony at 1 Hz, which is 45% slower than the heart. By means of histology and intravital imaging, we show that each antennal APO propels hemolymph into the antenna through an antennal vessel that traverses the length of the appendage and has an effective diameter of 1-2 μm. When hemolymph reaches the end of the appendage, it is discharged into the antennal hemocoel and returns to the head. Because a narrow vessel empties into a larger cavity, hemolymph travels up the antenna at 0.2 mm s(-1) but reduces its velocity by 75% as it returns to the head. Finally, treatment of mosquitoes with the anesthetic agent FlyNap (triethylamine) increases both antennal APO and heart contraction rates. In summary, this study presents a comprehensive functional characterization of circulatory physiology in the mosquito antennae.

  4. Nanosecond pulse electric field activation of platelet-rich plasma reduces myocardial infarct size and improves left ventricular mechanical function in the rabbit heart.

    Science.gov (United States)

    Hargrave, Barbara; Li, Francis

    2012-12-01

    In the current study, we used the novel, nonchemical method of nanosecond pulsed electric fields (nsPEF) to investigate the efficiency of a protocol involving the in vivo treatment of the ischemic and reperfused heart and heart cells in culture with platelet-rich plasma (PRP). Associated with the restoration of blood flow to the ischemic tissue is a phenomenon referred to as "ischemic reperfusion injury." Clinically a type of reperfusion injury occurs during coronary bypass surgery once blood perfusion to the heart is restarted. Although the restoration of oxygen to ischemic myocardial cells is critical for tissue survival, reperfusion causes myocardial oxidative stress, attributable in part to the increased production of reactive oxygen species (ROS). Enhanced ROS production is associated with mitochondrial damage. Adult female New Zealand white rabbits were anesthetized and a left thoracotomy performed to expose the heart. The distal segment of the left anterior descending coronary artery was occluded for 15 minutes and then released so reperfusion of the tissue could occur. PRP (.21 mg/heart) or saline was injected into the ischemic area of the myocardium. Mechanical function of the left ventricle was analyzed using a Millar catheter attached to a Micro-Med Analysis System. H9c2 cells in culture were treated with 1 mL of nsPEF activated PRP (1.05 mg/flask) for 24 hours before analysis for ROS production or mitochondrial depolarization damage). The left ventricle contracted and relaxed faster and infarct size was reduced in hearts treated with PRP compared with saline. ROS production and mitochondrial depolarization were reduced in H9c2 cells treated with PRP and stimulated with hydrogen peroxide. These results provide evidence that nsPEFs can successfully be used to prepare PRP and that the PRP is functional in heart protection possibly by reducing ROS generation and stabilizing the mitochondria of the ischemic/reperfused heart.

  5. Prospective ECG triggering reduces prosthetic heart valve-induced artefacts compared with retrospective ECG gating on 256-slice CT

    Energy Technology Data Exchange (ETDEWEB)

    Symersky, Petr [Academic Medical Center, Department of Cardiothoracic Surgery, Amsterdam (Netherlands); Habets, Jesse; Budde, Ricardo P.J. [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Westers, Paul [University Medical Center Utrecht, Department of Biostatistics, Julius Center for Health Sciences and Primary Care, Utrecht (Netherlands); Mol, Bas A.J.M. de [Academic Medical Center, Department of Cardiothoracic Surgery, Amsterdam (Netherlands); University of Technology Eindhoven, Department of Biomedical Engineering, Eindhoven (Netherlands); Prokop, Mathias [Radboud University Nijmegen Medical Center, Department of Radiology, Nijmegen (Netherlands)

    2012-06-15

    Multidetector computed tomography (MDCT) has diagnostic value for the evaluation of prosthetic heart valve (PHV) dysfunction but it is hampered by artefacts. We hypothesised that image acquisition using prospective triggering instead of retrospective gating would reduce artefacts related to pulsating PHV. In a pulsatile in vitro model, a mono- and bileaflet PHV were imaged using 256 MDCT at 60, 75 and 90 beats per minute (BPM) with either retrospective gating (120 kV, 600 mAs, pitch 0.2, CTDI{sub vol} 39.8 mGy) or prospective triggering (120 kV, 200 mAs, CTDI{sub vol} 13.3 mGy). Two thresholds (>175 and <-45HU), derived from the density of surrounding structures, were used for quantification of hyper- and hypodense artefacts. Image noise and artefacts were compared between protocols. Prospective triggering reduced hyperdense artefacts for both valves at every BPM (P = 0.001 all comparisons). Hypodense artefacts were reduced for the monoleaflet valve at 60 (P = 0.009), 75 (P = 0.016) and 90 BPM (P = 0.001), and for the bileaflet valves at 60 (P = 0.001), 90 (P = 0.001) but not at 75 BPM (P = 0.6). Prospective triggering reduced image noise at 60 (P = 0.001) and 75 (P < 0.03) but not at 90 BPM. Compared with retrospective gating, prospective triggering reduced most artefacts related to pulsating PHV in vitro. circle Computed tomographic images are often degraded by prosthetic heart valve-induced artefacts circle Prospective triggering reduces prosthetic heart valve-induced artefacts in vitro circle Artefact reduction at 90 beats per minute occurs without image noise reduction circle Prospective triggering may improve CT image quality of moving hyperdense structures. (orig.)

  6. Time-dependent biaxial mechanical behavior of the aortic heart valve leaflet.

    Science.gov (United States)

    Stella, John A; Liao, Jun; Sacks, Michael S

    2007-01-01

    . The relation between collagen fibril kinematics and mechanical properties in the mitral valve anterior leaflet. Journal of Biomechanical Engineering 129 (1), 78-87], we speculate that the mechanisms underlying this quasi-elastic behavior may be attributed to inter-fibrillar structures unique to valvular tissues. These mechanisms are an important functional aspect of native valvular tissues, and are likely critical to improve our understanding of valvular disease and help guide the development of valvular tissue engineering and surgical repair.

  7. Mechanisms increasing n-3 highly unsaturated fatty acids in the heart.

    Science.gov (United States)

    Glück, Tobias; Rupp, Heinz; Alter, Peter

    2016-03-01

    Due to ambiguous findings on cardiovascular benefits of systemic omega-3 fatty acid therapy, endogenous mechanisms contributing to local organ-specific concentrations of highly unsaturated fatty acids (HUFA) were examined. Using gas chromatography, 43 fatty acids were analyzed in atrial and ventricular myocardium and in pericardial fluid of male Wistar rats. To examine the endogenous fatty acid metabolism, precursors were administered into the pericardial sac. Pro- and anti-inflammatory actions were induced by talc or fenofibrate, respectively. Physical exercise and a sedentary obese state were used for increased beta-oxidation. DHA (22:6n-3) was increased in ventricular when compared with atrial myocardium (9.0 ± 2.1% vs. 4.7 ± 1.0%, p acid (24:5n-3) in atrial myocardium, which is a key precursor of DHA. In contrast, proinflammatory stimulation of the n-6 HUFA pathway did not influence the n-3 metabolism. Exercise- and obesity-induced increased beta-oxidation, the finalizing step of DHA synthesis, was associated with increased ventricular DHA concentrations (6.7 ± 1.0% vs. 8.4 ± 1.2%, p < 0.01). It is concluded that the endogenous metabolism contributes markedly to myocardial HUFA concentrations. The findings are supposed to influence the efficacy of oral HUFA treatment and provide a rationale for divergent findings of previous trials on omega-3 therapy.

  8. [Understanding heart failure].

    Science.gov (United States)

    Boo, José Fernando Guadalajara

    2006-01-01

    Heart failure is a disease with several definitions. The term "heart failure" is used by has brougth about confusion in the terminology. For this reason, the value of the ejection fraction (< 0.40 or < 0.35) is used in most meganalyses on the treatment of heart failure, avoiding the term "heart failure" that is a confounding concept. In this paper we carefully analyze the meaning of contractility, ventricular function or performance, preload, afterload, heart failure, compensation mechanisms in heart failure, myocardial oxygen consumption, inadequate, adequate and inappropriate hypertrophy, systole, diastole, compliance, problems of relaxation, and diastolic dysfunction. Their definitions are supported by the original scientific descriptions in an attempt to clarify the concepts about ventricular function and heart failure and, in this way, use the same scientific language about the meaning of ventricular function, heart failure, and diastolic dysfunction.

  9. Molecular mechanisms of AGE/RAGE-mediated fibrosis in the diabetic heart

    Science.gov (United States)

    Zhao, Jia; Randive, Rushil; Stewart, James A

    2014-01-01

    Chronic hyperglycemia is one of the main characteristics of diabetes. Persistent exposure to elevated glucose levels has been recognized as one of the major causal factors of diabetic complications. In pathologies, like type 2 diabetes mellitus (T2DM), mechanical and biochemical stimuli activate profibrotic signaling cascades resulting in myocardial fibrosis and subsequent impaired cardiac performance due to ventricular stiffness. High levels of glucose nonenzymatically react with long-lived proteins, such as collagen, to form advanced glycation end products (AGEs). AGE-modified collagen increase matrix stiffness making it resistant to hydrolytic turnover, resulting in an accumulation of extracellular matrix (ECM) proteins. AGEs account for many of the diabetic cardiovascular complications through their engagement of the receptor for AGE (RAGE). AGE/RAGE activation stimulates the secretion of numerous profibrotic growth factors, promotes increased collagen deposition leading to tissue fibrosis, as well as increased RAGE expression. To date, the AGE/RAGE cascade is not fully understood. In this review, we will discuss one of the major fibrotic signaling pathways, the AGE/RAGE signaling cascade, as well as propose an alternate pathway via Rap1a that may offer insight into cardiovascular ECM remodeling in T2DM. In a series of studies, we demonstrate a role for Rap1a in the regulation of fibrosis and myofibroblast differentiation in isolated diabetic and non-diabetic fibroblasts. While these studies are still in a preliminary stage, inhibiting Rap1a protein expression appears to down-regulate the molecular switch used to activate the ζ isotype of protein kinase C thereby promote AGE/RAGE-mediated fibrosis. PMID:25512788

  10. Low standard oral anticoagulation therapy for Chinese patients with St.Jude mechanical heart valves

    Institute of Scientific and Technical Information of China (English)

    孙晓刚; 胡盛寿; 祁国奇; 周玉燕

    2003-01-01

    Objective To study the efficacy of the low standard oral anticoagulation therapy following St Jude Medical (SJM) valve implantation for Chinese patients.Methods Totally 805 patients with a mean age of 42.70±11.09 years, enrolled into this study. Among them, 230 underwent aortic valve replacements (AVR), 381 mitral valve replacements (MVR), 189 double valve replacements (DVR) and 5 tricuspid valve replacememts (TVR). All patients received postoperative oral anticoagulation therapy based on a low standard of international normalized ratio (INR, 2.0-2.5). Of the 805 patients, 710 were followed up for 0.25-13 years (a median, 4.15 years). Results Postoperatively, 17 adverse events occurred. Operative mortality was 2.11%. The most frequent cause of operative mortality was a low cardiac output. During follow-up, there were 47 anticoagulant-induced hemorrhages [1.59%/patient-year (pt-yr)], 10 cases of thromboembolism (0.34%/pt-yr), and 3 mechanical valve thromboses (0.19%/pt-yr). There were 44 late deaths and the linearized late mortality rates were 0.51%pt-yr. Estimates of actuarial survival for all patients at 5 and 10 years was 97.45% (0.70%) and 77.96% (17.44%), respectively.Conclusions A low target INR range of 2.0-2.5 is preferable for Chinese patients so as to reduce the severe bleeding complications in those with conventionally higher levels of INR. The long-term results were satisfactory in terms of the numbers of those who suffered thrombosis, embolism and bleeding.

  11. Molecular mechanisms of AGE/RAGE-mediated fibrosis in the diabetic heart

    Institute of Scientific and Technical Information of China (English)

    Jia; Zhao; Rushil; Randive; James; A; Stewart

    2014-01-01

    Chronic hyperglycemia is one of the main characteristics of diabetes. Persistent exposure to elevated glucose levels has been recognized as one of the major causal factors of diabetic complications. In pathologies, like type 2 diabetes mellitus(T2DM), mechanical and biochemical stimuli activate profibrotic signaling cascades resulting in myocardial fibrosis and subsequent impaired cardiac performance due to ventricular stiffness. High levels of glucose nonenzymatically react with long-lived proteins, such as collagen, to form advanced glycation end products(AGEs). AGE-modified collagen increase matrix stiffness making it resistant to hydrolytic turnover, resulting in an accumulation of extracellular matrix(ECM) proteins. AGEs account for many of the diabetic cardiovascular complications through their engagement of the receptor for AGE(RAGE). AGE/RAGE activation stimulates the secretion of numerous profibrotic growth factors, promotes increased collagen deposition leading to tissue fibrosis, as well as increased RAGE expression. To date, the AGE/RAGE cascade is not fully understood. In this review, we willdiscuss one of the major fibrotic signaling pathways, the AGE/RAGE signaling cascade, as well as propose an alternate pathway via Rap1 a that may offer insight into cardiovascular ECM remodeling in T2 DM. In a series of studies, we demonstrate a role for Rap1 a in the regulation of fibrosis and myofibroblast differentiation in isolated diabetic and non-diabetic fibroblasts. While these studies are still in a preliminary stage, inhibiting Rap1 a protein expression appears to down-regulate the molecular switch used to activate the ζ isotype of protein kinase C thereby promote AGE/RAGE-mediated fibrosis.

  12. In vitro heart valve testing: steady versus pulsatile flow.

    Science.gov (United States)

    Black, M M; Hose, D R; Lamb, C J; Lawford, P V; Ralph, S J

    1994-03-01

    The design of artificial heart valves has traditionally been based on the development of a prototype device which was then subjected to extensive laboratory testing in order to confirm its suitability for clinical use. In the past the in vitro assessment of a valve's performance was based principally on the measurement of parameters such as pressure difference, regurgitation and, more recently, energy losses. Such measurements can be defined as being at the 'macro' level and rarely show any clinically significant differences amongst currently available prostheses. The analytical approach to flow through heart valves has previously been hampered by difficulties experienced in solving the relevant equations of flow particularly in the case of pulsatile conditions. Computational techniques are now available which enable appropriate solutions to be obtained for these problems and consequently provide an opportunity for detailed examination of the 'micro' level of flow disturbances exhibited by the different valves. This present preliminary study is designed to illustrate the use of such an analytical approach to the flow through prosthetic valves. A single topic has been selected for this purpose which is the comparative value of steady versus pulsatile flow testing. A bileaflet valve was chosen for the analysis and a mathematical model of this valve in the aortic position of the Sheffield Pulse Duplicator was created. The theoretical analysis was carried out using a commercially available Computational Fluid Dynamics package, namely, FIDAP, on a SUN MICROSYSTEMS 10-30 workstation.(ABSTRACT TRUNCATED AT 250 WORDS)

  13. Mechanisms of Chinese Medicine Xinmailong’s protection against heart failure in pressure-overloaded mice and cultured cardiomyocytes

    Science.gov (United States)

    Qi, Jianyong; Yu, Juan; Tan, Yafang; Chen, Renshan; Xu, Wen; Chen, Yanfen; Lu, Jun; Liu, Qin; Wu, Jiashin; Gu, Weiwang; Zhang, Minzhou

    2017-01-01

    Patients with heart failure (HF) have high mortality and mobility. Xinmailong (XML) injection, a Chinese Medicine, is clinically effective in treating HF. However, the mechanism of XML’s effectiveness on HF was unclear, and thus, was the target of the present study. We created a mouse model of pressure-overload-induced HF with transverse aortic constriction (TAC) surgery and compared among 4 study groups: SHAM (n = 10), TAC (n = 12), MET (metoprolol, positive drug treatment, n = 7) and XML (XML treatment, n = 14). Dynamic changes in cardiac structure and function were evaluated with echocardiography in vivo. In addition, H9C2 rat cardiomyocytes were cultured in vitro and the phosphorylation of ERK1/2, AKT, GSK3β and protein expression of GATA4 in nucleus were detected with Western blot experiment. The results showed that XML reduced diastolic thickness of left ventricular posterior wall, increased ejection fraction and fraction shortening, so as to inhibit HF at 2 weeks after TAC. Moreover, XML inhibited the phosphorylation of ERK1/2, AKT and GSK3β, subsequently inhibiting protein expression of GATA4 in nucleus (P < 0.001). Together, our data demonstrated that XML inhibited the TAC-induced HF via inactivating the ERK1/2, AKT/GSK3β, and GATA4 signaling pathway. PMID:28205629

  14. Long-chain n-3 polyunsaturated fatty acids: new insights into mechanisms relating to inflammation and coronary heart disease.

    Science.gov (United States)

    de Roos, Baukje; Mavrommatis, Yiannis; Brouwer, Ingeborg A

    2009-09-01

    Evidence from observational studies, prospective cohort studies and randomized clinical intervention studies indicate that moderate doses of long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFA) significantly decrease risk of fatal coronary heart disease (CHD). Higher doses and longer duration of intervention may also protect from non-fatal CHD events. The exact mechanisms through which LC n-3 PUFA has an effect on CHD are not well established but may include a decrease in fasting and postprandial triacylglycerol levels, a decrease in arrhythmias, modulation of platelet aggregation and decreased synthesis of pro-inflammatory agents. The mechanistic relation between LC n-3 PUFA and inflammation has attracted great interest, and in vitro studies have revealed that these fatty acids decrease endothelial activation, affect eicosanoid metabolism (including epoxygenation pathways) and induce inflammatory resolution. However, the effects of LC n-3 PUFA on established biomarkers of inflammation and endothelial activation in vivo are not strong. Consequently we need new and more sensitive and systemic biomarkers to reveal the effects of LC n-3 PUFA on localized inflammatory processes.

  15. Obesity and natriuretic peptides, BNP and NT-proBNP: mechanisms and diagnostic implications for heart failure.

    Science.gov (United States)

    Madamanchi, Chaitanya; Alhosaini, Hassan; Sumida, Arihiro; Runge, Marschall S

    2014-10-20

    Many advances have been made in the diagnosis and management of heart failure (HF) in recent years. Cardiac biomarkers are an essential tool for clinicians: point of care B-type natriuretic peptide (BNP) and its N-terminal counterpart (NT-proBNP) levels help distinguish cardiac from non-cardiac causes of dyspnea and are also useful in the prognosis and monitoring of the efficacy of therapy. One of the major limitations of HF biomarkers is in obese patients where the relationship between BNP and NT-proBNP levels and myocardial stiffness is complex. Recent data suggest an inverse relationship between BNP and NT-proBNP levels and body mass index. Given the ever-increasing prevalence of obesity world-wide, it is important to understand the benefits and limitations of HF biomarkers in this population. This review will explore the biology, physiology, and pathophysiology of these peptides and the cardiac endocrine paradox in HF. We also examine the clinical evidence, mechanisms, and plausible biological explanations for the discord between BNP levels and HF in obese patients.

  16. Limited dose warfarin throughout pregnancy in patients with mechanical heart valve prosthesis: a meta-analysis.

    Science.gov (United States)

    Hassouna, Ahmed; Allam, Hemat

    2014-06-01

    The continuation of warfarin throughout pregnancy in patients with a mechanical valve prosthesis is a valid anticoagulation regimen, provided that warfarin dose does not exceed 5 mg/day. Two decades after being introduced, the efficacy and safety of this regimen merit evaluation. We performed a systematic review for cases published between January 1991 and January 2013. We compiled our prospective data on 55 pregnancies and calculated pooled estimates (95% confidence interval) of adverse foetal and maternal outcomes. Events were expressed as proportions of total pregnancies, except embryopathy and maternal death, which were related to the number of live births and number of patients, respectively. There were 494 eligible pregnancies reported in 11 studies. The rate of embryopathy was 0.9% (0.4-2.4%) and most of the 13.4% (8.4-24.7%) foetal losses were due to the 12.8% (7.7-22.7%) rate of spontaneous abortion. No maternal mortality was encountered (0-1.3%) but 0.6% (0.3-2%) prosthetic valve thrombosis, 1.8% (1.1-3.6%) total thromboembolic events and 3.4% (2-5.1%) major maternal bleeding events were recorded. Foetal loss, spontaneous abortions and foetal embryopathy dropped to 8.1% (2.9-13.7%), 7.3% (3.1-11.8%) and 0.6% (0.1-2.1%) among the 344 pregnancies (69.6%) observed in the 6 prospective studies (54.5%). Prosthetic valve thrombosis (0.6%; 01-2%), total thromboembolic (2.3%; 1.2-4.6%) and major bleeding events (2.9%; 1.8-6%) remained comparable with overall results. Foetal embryopathy and prosthetic valve thrombosis were not robust on sensitivity analysis, regardless of the study design. A prospective subgroup of 96 patients (19.4%) received smaller warfarin dose, through targeting a lower international normalized ratio (INR) between 1.5 and 2.5. The associated rate of foetal loss (2.1%; 0.5-6.9%) was significantly lower than that observed in the remaining patients targeting a higher INR between 2.5 and 3.5 (16.1%; 13.1-34.4%). Adverse maternal outcomes were

  17. Clinical Update: Cardiovascular Disease in Diabetes Mellitus: Atherosclerotic Cardiovascular Disease and Heart Failure in Type 2 Diabetes Mellitus - Mechanisms, Management, and Clinical Considerations.

    Science.gov (United States)

    Low Wang, Cecilia C; Hess, Connie N; Hiatt, William R; Goldfine, Allison B

    2016-06-14

    Cardiovascular disease remains the principal cause of death and disability among patients with diabetes mellitus. Diabetes mellitus exacerbates mechanisms underlying atherosclerosis and heart failure. Unfortunately, these mechanisms are not adequately modulated by therapeutic strategies focusing solely on optimal glycemic control with currently available drugs or approaches. In the setting of multifactorial risk reduction with statins and other lipid-lowering agents, antihypertensive therapies, and antihyperglycemic treatment strategies, cardiovascular complication rates are falling, yet remain higher for patients with diabetes mellitus than for those without. This review considers the mechanisms, history, controversies, new pharmacological agents, and recent evidence for current guidelines for cardiovascular management in the patient with diabetes mellitus to support evidence-based care in the patient with diabetes mellitus and heart disease outside of the acute care setting.

  18. [The assessment of mechanical heart valves stenosis in adults after aortic valve replacement: the advantage of full-flow design of mechanical valve].

    Science.gov (United States)

    Bokeria, L A; Bokeria, O L; Fadeev, A A; Makhachev, O A; Kosareva, T I; Averina, I I

    2013-01-01

    The analysis of transprosthetic hemodynamics in adults after aortic valve replacement in the Bakoulev Center for Cardiovascular Surgery in 2007-2010 demonstrated the hemodynamic advantage of the concept of new full-flow mechanical aortic valve prosthesis "CorBeat". Having the same size of internal orifice and tissue annulus diameters, the values of transprosthetic parameters (peak and mean gradients, blood flow velocities) through "CorBeat" were close to physiological values of transvalvular native aortic parameters and had a tendency to be not dependent on the size of prosthesis (p = 0.63). In the article for the first time a morphometric database of geometric values of internal orifice area of normal native aortic valves in adults was used taking into account both the gender and the body surface area's of a patient. There was also used the standardized prosthesis size Z-score which represents the number of SDs by which the internal prosthesis area differs from the mean normal native aortic valve area for the patient's body surface area. The article emphasizes the need of the personal selection of the size and the type of prosthesis for any patient as well as the need for new design development of prosthetic heart valves.

  19. Short-term mechanical circulatory support by veno-arterial extracorporeal membrane oxygenation in the management of cardiogenic shock and end-stage heart failure.

    Science.gov (United States)

    Brugts, Jasper J; Caliskan, Kadir

    2014-02-01

    Despite modern treatment modalities, cardiogenic shock is associated with a very high risk of mortality and morbidity. The short- and long-term survival in patients with cardiogenic shock or end-stage heart failure has improved considerably by recent technological advances in short and long-term mechanical circulatory support devices. For short-term mechanical support, veno-arterial extracorporeal membrane oxygenation (VA-ECMO) has been increasingly used as bridge-to-decision and bridge-to-recovery in cardiogenic shock patients. Long-term mechanical circulatory support devices such as left ventricular assist devices (LVADs) are widely available and play a central role in bridge-to-transplantation in those eligible for heart transplantation (HTX) and as destination therapy (DT) in those not eligible for heart transplantation. Nevertheless, patients with critical cardiogenic shock show a deleterious outcome after LVAD-implantation or HTX with higher mortality, more complications and higher burden on financial resources. These considerations underscore the importance of optimal timing and appropriate patient selection for eventual LVAD therapy. The current report will focus on the immediate management of patients with cardiogenic shock with inotropes, discuss the use of IABP and focus mainly on pivotal choices to be made in the period spanned by short term mechanical circulatory support in patients with refractory cardiogenic shock.

  20. Strategies and outcomes of periprocedural bridging therapy with low-molecular-weight heparin in patients with mechanical heart valves.

    Science.gov (United States)

    Schulman, Jacqueline M; Majeed, Ammar; Mattsson, Eva; Schulman, Sam; Holmström, Margareta; Ågren, Anna

    2015-11-01

    Patients with mechanical heart valves (MHV) undergoing invasive procedures often receive periprocedural bridging with low-molecular-weight heparin (LMWH). The bridging strategies used in real-life and the predictors for bleeding and thrombosis are not well studied. We retrospectively assessed patients with MHV that underwent invasive procedures requiring vitamin K antagonist interruption and LMWH bridging. Thromboembolic and bleeding events occurring up to 30 days after the procedures were recorded. Predictors of major bleeding events (MBEs) were analyzed with logistic regression. We evaluated 547 patients with MHV who underwent 275 procedures during a 6.5-year period. Bridging with LMWH was used in 185 procedures in a total of 117 patients. Combined pre- and post-operative bridging was the most frequently employed (63 %). Doses of LMWH were prophylactic in 96 (52 %) of the procedures and therapeutic in 89 (48 %). The procedure-related bleeding risk was evaluated as high in 70 (38 %) and low in 115 (62 %) of the procedures. There was a trend to more frequent use of prophylactic doses (61 %) in high-risk surgery, and more therapeutic doses (53 %) in low-risk ones. There were 36 bleeding episodes, 21 (11 % of procedures) of which were classified as MBEs, but there were no thromboembolic events. Most MBEs (n = 14; 67 %) occurred in surgeries with high bleeding risk. In the multivariate analysis, the bleeding risk of the surgery itself was the only independent predictor for MBEs. For patients with MHV receiving perioperative bridging with LMWH, the major predictor for MBE is the bleeding risk of the surgery.

  1. A novel left heart simulator for the multi-modality characterization of native mitral valve geometry and fluid mechanics.

    Science.gov (United States)

    Rabbah, Jean-Pierre; Saikrishnan, Neelakantan; Yoganathan, Ajit P

    2013-02-01

    Numerical models of the mitral valve have been used to elucidate mitral valve function and mechanics. These models have evolved from simple two-dimensional approximations to complex three-dimensional fully coupled fluid structure interaction models. However, to date these models lack direct one-to-one experimental validation. As computational solvers vary considerably, experimental benchmark data are critically important to ensure model accuracy. In this study, a novel left heart simulator was designed specifically for the validation of numerical mitral valve models. Several distinct experimental techniques were collectively performed to resolve mitral valve geometry and hemodynamics. In particular, micro-computed tomography was used to obtain accurate and high-resolution (39 μm voxel) native valvular anatomy, which included the mitral leaflets, chordae tendinae, and papillary muscles. Three-dimensional echocardiography was used to obtain systolic leaflet geometry. Stereoscopic digital particle image velocimetry provided all three components of fluid velocity through the mitral valve, resolved every 25 ms in the cardiac cycle. A strong central filling jet (V ~ 0.6 m/s) was observed during peak systole with minimal out-of-plane velocities. In addition, physiologic hemodynamic boundary conditions were defined and all data were synchronously acquired through a central trigger. Finally, the simulator is a precisely controlled environment, in which flow conditions and geometry can be systematically prescribed and resultant valvular function and hemodynamics assessed. Thus, this work represents the first comprehensive database of high fidelity experimental data, critical for extensive validation of mitral valve fluid structure interaction simulations.

  2. Ultrasound-targeted transfection of tissue-type plasminogen activator gene carried by albumin nanoparticles to dog myocardium to prevent thrombosis after heart mechanical valve replacement

    Directory of Open Access Journals (Sweden)

    Ji J

    2012-06-01

    Full Text Available Ji Jun, Ji Shang-Yi, Yang Jian-An, He Xia, Yang Xiao-Han, Ling Wen-Ping, Chen Xiao-LingDepartment of Pathology and Cardiovascular Surgery, Shenzhen Sun Yat-Sen Cardiovascular Hospital, Shenzhen, Guangdong, People's Republic of ChinaBackground: There are more than 300,000 prosthetic heart valve replacements each year worldwide. These patients are faced with a higher risk of thromboembolic events after heart valve surgery and long-term or even life-long anticoagulative and antiplatelet therapies are necessary. Some severe complications such as hemorrhaging or rebound thrombosis can occur when the therapy ceases. Tissue-type plasminogen activator (t-PA is a thrombolytic agent. One of the best strategies is gene therapy, which offers a local high expression of t-PA over a prolonged time period to avoid both systemic hemorrhaging and local rebound thrombosis. There are some issues with t-PA that need to be addressed: currently, there is no up-to-date report on how the t-PA gene targets the heart in vivo and the gene vector for t-PA needs to be determined.Aims: To fabricate an albumin nano-t-PA gene ultrasound-targeted agent and investigate its targeting effect on prevention of thrombosis after heart mechanic valve replacement under therapeutic ultrasound.Methods: A dog model of mechanical tricuspid valve replacement was constructed. A highly expressive t-PA gene plasmid was constructed and packaged by nanoparticles prepared with bovine serum albumin. This nanopackaged t-PA gene plasmid was further cross-linked to ultrasonic microbubbles prepared with sucrose and bovine serum albumin to form the ultrasonic-targeted agent for t-PA gene transfection. The agent was given intravenously followed by a therapeutic ultrasound treatment (1 MHz, 1.5 w/cm2, 10 minutes of the heart soon after valve replacement had been performed. The expression of t-PA in myocardium was detected with multiclonal antibodies to t-PA by the indirect immunohistochemical method

  3. Heart Disease

    Science.gov (United States)

    ... daily aspirin to prevent heart attack? Does taking birth control pills increase my risk for heart disease? Does using ... tells you to. Return to top Does taking birth control pills increase my risk for heart disease? Taking birth ...

  4. Estimation of torque on mechanical heart valves due to magnetic resonance imaging including an estimation of the significance of the Lenz effect using a computational model

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, Neil M. [44 Ardgowan Street, Greenock PA16 8EL (United Kingdom). E-mail: neil.robertson at physics.org; Diaz-Gomez, Manuel [Plaza Alcalde Horacio Hermoso, 2, 3-A 41013 Seville (Spain). E-mail: manolo-diaz at latinmail.com; Condon, Barrie [Department of Clinical Physics, Institute of Neurological Sciences, Glasgow G51 4TF (United Kingdom). E-mail: barrie.condon at udcf.gla.ac.uk

    2000-12-01

    Mitral and aortic valve replacement is a procedure which is common in cardiac surgery. Some of these replacement valves are mechanical and contain moving metal parts. Should the patient in whom such a valve has been implanted be involved in magnetic resonance imaging, there is a possible dangerous interaction between the moving metal parts and the static magnetic field due to the Lenz effect. Mathematical models of two relatively common forms of single-leaflet valves have been derived and the magnitude of the torque which opposes the motion of the valve leaflet has been calculated for a valve disc of solid metal. In addition, a differential model of a ring-strengthener valve type has been considered to determine the likely significance of the Lenz effect in the context of the human heart. For common magnetic field strengths at present, i.e. 1 to 2 T, the effect is not particularly significant. However, there is a marked increase in back pressure as static magnetic field strength increases. There are concerns that, since field strengths in the range 3 to 4 T are increasingly being used, the Lenz effect could become significant. At 5 to 10 T the malfunction of the mechanical heart valve could cause the heart to behave as though it is diseased. For unhealthy or old patients this could possibly prove fatal. (author)

  5. Multidetector CT imaging of mechanical prosthetic heart valves : quantification of artifacts with a pulsatile in-vitro model

    NARCIS (Netherlands)

    Symersky, Petr; Budde, Ricardo P. J.; Westers, Paul; de Mol, Bas A. J. M.; Prokop, Mathias

    2011-01-01

    Objectives Multidetector computed tomography (MDCT) can detect the cause of prosthetic heart valve (PHV) dysfunction but is hampered by valve-induced artifacts. We quantified artifacts of four PHV using a pulsatile in-vitro model and assessed the relation to leaflet motion and valve design. Methods

  6. Use of the Frog Heart Preparation to Teach Students about the Spontaneous Mechanical Activity of the Vena Cava

    Science.gov (United States)

    Hill, Brent J. F.; Goodman, Ian; Moran, William M.

    2011-01-01

    Most undergraduate physiology texts describe veins simply as reservoirs for blood and conduits for return of blood to the heart. This article describes a laboratory exercise that can be performed by students to demonstrate that veins are much more than reservoirs and conduits for blood flow: they possess a dynamic rhythmic contraction. In this…

  7. Multidetector CT imaging of mechanical prosthetic heart valves: quantification of artifacts with a pulsatile in-vitro model

    NARCIS (Netherlands)

    Symersky, P.; Budde, R.P.; Westers, P.; Mol, B.A. de; Prokop, M.

    2011-01-01

    OBJECTIVES: Multidetector computed tomography (MDCT) can detect the cause of prosthetic heart valve (PHV) dysfunction but is hampered by valve-induced artifacts. We quantified artifacts of four PHV using a pulsatile in-vitro model and assessed the relation to leaflet motion and valve design. METHODS

  8. Multidetector CT imaging of mechanical prosthetic heart valves: quantification of artifacts with a pulsatile in-vitro model

    NARCIS (Netherlands)

    Symersky, P.; Budde, R.P.J.; Westers, P.; de Mol, B.A.J.M.; Prokop, M.

    2011-01-01

    Multidetector computed tomography (MDCT) can detect the cause of prosthetic heart valve (PHV) dysfunction but is hampered by valve-induced artifacts. We quantified artifacts of four PHV using a pulsatile in-vitro model and assessed the relation to leaflet motion and valve design. A Medtronic Hall ti

  9. Calcium sensitivity and the Frank-Starling mechanism of the heart are increased in titin N2B region deficient mice

    Science.gov (United States)

    Lee, Eun-Jeong; Peng, Jun; Radke, Michael; Gotthardt, Michael; Granzier, Henk L

    2010-01-01

    Previous work suggests that titin-based passive tension is a factor in the Frank-Starling mechanism of the heart, by increasing length-dependent activation (LDA) through an increase in calcium sensitivity at long sarcomere length. We tested this hypothesis in a mouse model (N2B KO model) in which titin-based passive tension is elevated as a result of the excision of the N2B element, one of cardiac titin’s spring elements. LDA was assessed by measuring the active tension-pCa (−log[Ca2+]) relationship at sarcomere length (SLs) of 1.95, 2.10 and 2.30 µm in WT and N2B KO skinned myocardium. LDA was positively correlated with titin-based passive tension, due to an increase in calcium sensitivity at the longer SLs in the KO. For example, at pCa 6.0 the KO:WT tension ratio was 1.28 ± 0.07 and 1.42 ± 0.04 at SLs of 2.1 and 2.3 µm, respectively. There was no difference in protein expression or phosphorylation of sarcomeric proteins. We also measured the calcium sensitivity after PKA treating the skinned muscle and found that titin-based passive tension was also now correlated with LDA, with a slope that was significantly increased compared to no PKA treatment. Finally, we performed isolated heart experiments and measured the Frank-Starling relation (slope of developed wall stress-LV volume relation) as well as diastolic stiffness (slope of diastolic wall stress – volume relation). The FSM was more pronounced in the N2B KO hearts and the slope of the FSM correlated with diastolic stiffness. These findings support that titin-based passive tension triggers an increase in calcium sensitivity at long sarcomere length, thereby playing an important role in the Frank-Starling mechanism of the heart. PMID:20507834

  10. Calcium sensitivity and the Frank-Starling mechanism of the heart are increased in titin N2B region-deficient mice.

    Science.gov (United States)

    Lee, Eun-Jeong; Peng, Jun; Radke, Michael; Gotthardt, Michael; Granzier, Henk L

    2010-09-01

    Previous work suggests that titin-based passive tension is a factor in the Frank-Starling mechanism of the heart, by increasing length-dependent activation (LDA) through an increase in calcium sensitivity at long sarcomere length. We tested this hypothesis in a mouse model (N2B KO model) in which titin-based passive tension is elevated as a result of the excision of the N2B element, one of cardiac titin's spring elements. LDA was assessed by measuring the active tension-pCa (-log[Ca(2+)]) relationship at sarcomere length (SLs) of 1.95, 2.10, and 2.30 microm in WT and N2B KO skinned myocardium. LDA was positively correlated with titin-based passive tension due to an increase in calcium sensitivity at the longer SLs in the KO. For example, at pCa 6.0, the KO:WT tension ratio was 1.28+/-0.07 and 1.42+/-0.04 at SLs of 2.1 and 2.3 microm, respectively. There was no difference in protein expression or total phosphorylation of sarcomeric proteins. We also measured the calcium sensitivity after PKA treating the skinned muscle and found that titin-based passive tension was also now correlated with LDA, with a slope that was significantly increased compared to no PKA treatment. Finally, we performed isolated heart experiments and measured the Frank-Starling relation (slope of developed wall stress-LV volume relation) as well as diastolic stiffness (slope of diastolic wall stress-volume relation). The FSM was more pronounced in the N2B KO hearts and the slope of the FSM correlated with diastolic stiffness. These findings support that titin-based passive tension triggers an increase in calcium sensitivity at long sarcomere length, thereby playing an important role in the Frank-Starling mechanism of the heart.

  11. Low radiation dose non-contrast cardiac CT: is it of value in the evaluation of mechanical aortic valve

    Energy Technology Data Exchange (ETDEWEB)

    Bazeed, Mohamed Fayez (Dept. of Diagnostic Radiology, Faculty of Medicine, Mansoura Univ. (Egypt)), email: m_bazeed@yahoo.com; Moselhy, Mohamed Saleh (Cardiology Dept. Faculty of Medicine, Suez Canal Univ. (Egypt)); Rezk, Ahmad Ibrahim (Dept. of Cardiac Surgery, Faculty of Medicine, Aim Shams Univ. (Egypt)); Al-Murayeh, Mushabab Ayedh (Dept. of Cardiac Services, Armed Forces Hospitals Southern Region (Saudi Arabia))

    2012-05-15

    Background: Prosthetic bileaflet mechanical valve function has been traditionally evaluated using echocardiography and fluoroscopy. Multidetector computed tomography (MDCT) is a novel technique for cardiac evaluation. Purpose: To evaluate bileaflet mechanical aortic valves using a low-milliampere (mA), non-contrast MDCT protocol with a limited scan range. Material and Methods: Forty patients with a bileaflet mechanical aortic valve were evaluated using a non-contrast, low-mA, ECG-gated 64 MDCT protocol with a limited scan range. MDCT findings of opening and closing valve angles were correlated to fluoroscopy and echocardiography. Also, the valve visibility was evaluated on MDCT and fluoroscopy according to a 3-point grading scale. Results: The visualization score with the MDCT was significantly superior to the fluoroscopy (3 vs. 2.7). A strong correlation was noted between the opening (r = 0.82) and closing (r = 0.96) valve angles with MDCT and fluoroscopy without a statistically significant difference (P = 0.31 and 0.16, respectively). The mean effective radiation dose of the suggested protocol was 4 +- 0.5 mSv. Five valves were evaluated using transesophageal echocardiography because the valves were difficult to evaluate with transthoracic echocardiography, and all of these valves were evaluated optimally with MDCT. A high-pressure gradient was noted in nine valves, and the MDCT showed that seven of these valves inadequately opened, and two valves opened well, which resulted in patient valve mismatch. Incomplete valve closure was noted in five valves, and the echocardiography showed significant transvalvular regurgitation in all five valves. Conclusion: MDCT can provide a precise measurement of valve function and can potentially evaluate high-pressure gradients and transvalvular regurgitation

  12. Heart Diseases

    Science.gov (United States)

    ... you're like most people, you think that heart disease is a problem for others. But heart disease is the number one killer in the U.S. ... of disability. There are many different forms of heart disease. The most common cause of heart disease is ...

  13. Heart Transplantation

    Science.gov (United States)

    A heart transplant removes a damaged or diseased heart and replaces it with a healthy one. The healthy heart comes from a donor who has died. It is the last resort for people with heart failure when all other treatments have failed. The ...

  14. The total artificial heart.

    Science.gov (United States)

    Cook, Jason A; Shah, Keyur B; Quader, Mohammed A; Cooke, Richard H; Kasirajan, Vigneshwar; Rao, Kris K; Smallfield, Melissa C; Tchoukina, Inna; Tang, Daniel G

    2015-12-01

    The total artificial heart (TAH) is a form of mechanical circulatory support in which the patient's native ventricles and valves are explanted and replaced by a pneumatically powered artificial heart. Currently, the TAH is approved for use in end-stage biventricular heart failure as a bridge to heart transplantation. However, with an increasing global burden of cardiovascular disease and congestive heart failure, the number of patients with end-stage heart failure awaiting heart transplantation now far exceeds the number of available hearts. As a result, the use of mechanical circulatory support, including the TAH and left ventricular assist device (LVAD), is growing exponentially. The LVAD is already widely used as destination therapy, and destination therapy for the TAH is under investigation. While most patients requiring mechanical circulatory support are effectively treated with LVADs, there is a subset of patients with concurrent right ventricular failure or major structural barriers to LVAD placement in whom TAH may be more appropriate. The history, indications, surgical implantation, post device management, outcomes, complications, and future direction of the TAH are discussed in this review.

  15. Theory of heart

    Energy Technology Data Exchange (ETDEWEB)

    Glass, L. (ed.) (McGill Univ., Montreal (Canada). Dept. of Physiology); Hunter, P. (ed.) (Auckland Univ., Auckland (New Zealand). Dept. of Engineering Science); McCulloch, A. (ed.) (California Univ., San Diego (United States))

    1991-01-01

    In recent years there has been a growth in interest in studying the heart from the perspective of the physical sciences: mechanics, fluid flow, electromechanics. This volume is the result of a workshop held in July 1989 at the Institute for Nonlinear Sciences at the University of California at San Diego that brought together scientists and clinicians with graduate students and postdoctoral fellows who share an interest in the heart. The chapters were prepared by the invited speakers as didactic reviews of their subjects but also include up-to-date results in their fields. Topics covered include the structure, mechanical properties, and function of the heart and the myocardium, electrical activity of the heart and myocardium, and mathematical models of heart function. Individual chapters are abstracted separately.

  16. Effects of high fat-, cholesterol-enriched diet on the antioxidant defence mechanisms in the rabbit heart.

    Science.gov (United States)

    Lapenna, D; Del Boccio, G; Porreca, E; Pennelli, A; Mezzetti, A; De Gioia, S; Marzio, L; Di Ilio, C; Cuccurullo, F

    1992-01-01

    In 7 rabbits fed on hyperlipidic diet (0.5% cholesterol, 5% peanut oil and 5% lard) for 4 weeks, the ventricular myocardium was tested for antioxidant defences and thiobarbituric acid reactive substances. Seven age-matched rabbits served as controls. The hearts were previously subjected to 45 min Langendorff perfusion to study coronary flow, developed tension and resting tension; coronary effluent values of CPK activity, pH and UV absorbance at 250 nm (i.e., low molecular weight ATP catabolites) were also investigated. After 4 weeks of diet, a significant rise of plasma cholesterol (P effluent of hyperlipidemic rabbits. In conclusion, high fat-, cholesterol-enriched diet induces an imbalance in the rabbit heart antioxidant defences, some of which are increased, whereas others are depressed, eventually resulting in enhanced myocardial lipid peroxidation. These biochemical changes are associated with higher perfusate values of UV absorbance at 250 nm, but not with significant CPK leakage or myocardial hemodynamics derangement.

  17. Valveless pumping mechanics of the embryonic heart during cardiac looping: Pressure and flow through micro-PIV.

    Science.gov (United States)

    Bark, D L; Johnson, B; Garrity, D; Dasi, L P

    2017-01-04

    Cardiovascular development is influenced by the flow-induced stress environment originating from cardiac biomechanics. To characterize the stress environment, it is necessary to quantify flow and pressure. Here, we quantify the flow field in a developing zebrafish heart during the looping stage through micro-particle imaging velocimetry and by analyzing spatiotemporal plots. We further build upon previous methods to noninvasively quantify the pressure field at a low Reynolds number using flow field data for the first time, while also comparing the impact of viscosity models. Through this method, we show that the atrium builds up pressure to ~0.25mmHg relative to the ventricle during atrial systole and that atrial expansion creates a pressure difference of ~0.15mmHg across the atrium, resulting in efficient cardiac pumping. With these techniques, it is possible to noninvasively fully characterize hemodynamics during heart development.

  18. Similar oxygen cost of myocardial contractility between DPI 201-106 and epinephrine despite different subcellular mechanisms of action in dog hearts.

    Science.gov (United States)

    Futaki, S; Goto, Y; Ohgoshi, Y; Yaku, H; Suga, H

    1992-01-01

    The effects of DPI 201-106 (a novel, cyclic AMP-independent positive inotropic agent with Ca(2+)-sensitizing and Na(+)-channel agonistic mechanisms) on myocardial mechanics and energetics were assessed in the excised cross-circulated dog left ventricle. In the first protocol, the relation between left ventricular oxygen consumption (VO2) and systolic pressure-volume area (PVA) was analyzed before and during administration of DPI 201-106. The reciprocal of the slope of the VO2-PVA relation has been shown to reflect the contractile efficiency, and the VO2-intercept consists of the oxygen cost of contractility-dependent excitation-contraction coupling and basal metabolism. DPI 201-106 increased Emax (contractility index) and elevated the VO2-PVA relation in a parallel manner, i.e., the VO2-intercept increased without a change in the slope. In the second protocol, the increase in the VO2-intercept of the VO2-PVA relation for a unit increase in Emax (i.e., oxygen cost of enhanced contractility) was compared between DPI 201-106 and epinephrine in a paired manner in each heart. Epinephrine significantly abbreviated the time to end systole, whereas DPI 201-106 did not, suggesting that the mechanism of inotropic action differed between the two drugs. However, the oxygen cost of enhanced contractility was the same between the two drugs in each heart. Therefore, DPI 201-106 did not alter the contractile efficiency nor spare the oxygen cost of enhanced contractility as compared to epinephrine under the present experimental conditions. This suggests that the Ca(2+)-sensitizing effect of DPI 201-106, if any, is too small to spare the oxygen cost of contractility in the blood-perfused, non-failing dog heart.

  19. THE IMPACT OF A SINGLE AND CONTINUOUS AUDIOVISUAL STIMULATION ON HEART RATE VARIABILITY AND MECHANISMS OF AUTONOMIC REGULATION IN ATHLETES-CYCLICS

    Directory of Open Access Journals (Sweden)

    R. I. Aizman

    2014-01-01

    Full Text Available The purpose of this study was to investigate the effect of influence of single and prolonged exposure of audio-visual stimulation (AVS on heart rate variability and the mechanisms of the autonomic regulation in athletes, involved in cyclic sports activity.Material and methods. In this study 60 athletes aging of 17–23 years old, specializing in middle-distance running, were involved. The running volume in the zones of varying intensity was from 185 to 225 km/month. The experiment was conducted in January – March 2014, at the Scientific Educational Center “Physiology of ontogenesis” at the Department of Anatomy, Physiology and Life Safety of NSPU.Training course of audiovisual stimulation (AVS consisted of 20–22 sessions, which were conducted in a day with using a portable audiovisual stimulator “NOVO PRO” (USA. ECG registration signal was performed using hardware and software complex VNS-Micro (Neurosoft, Ivanovo, Russia in standard electrocardiogram lead II. Athletes who received AVS course in the morning, before sports training loads, have received training with activating program, and after exercise – by using a relaxed program.Results. In athletes after 20–22 sessions of AVS the decreased influence of the sympathetic regulation and contribution of central levels of management in the regulation of heart rate were found. A decrease of intensity of regulatory system was observed.Increased influence of the parasympathetic regulation and strengthening of autonomous regulation contour was found. AVS contributed to increasing influence of respiratory waves on the heart rhythm and a more economical functional activity. AVS single exposure caused a significant increase in the functioning of autonomous regulation contour, the growing influence of parasympathetic effects and higher contribution of respiratory waves in the formation of heart rate by using activating as well relaxing programs. However, a more pronounced effect was

  20. Fatty acids are important for the Frank-Starling mechanism and Gregg effect but not for catecholamine response in isolated rat hearts.

    Science.gov (United States)

    Pagliaro, P; Chiribiri, A; Gattullo, D; Penna, C; Rastaldo, R; Recchia, F A

    2002-11-01

    In some pathophysiological conditions myocardial metabolism can switch from mainly long chain fatty acid (LCFA) oxidation to mainly glucose oxidation. Whether the predominant fatty acid or glucose oxidation affects cardiac performance has not been defined. In a buffer perfused isovolumetrically contracting rat heart, oxidation of endogenous pool LCFA was avoided by inhibiting carnitine-palmitoyl-transferase I (CPT-I) with oxfenicine (2 mM). In order to restore fatty acid oxidation, hexanoate (1 mM), which bypasses CPT-I inhibition, was added to the perfusate. Three groups of hearts were subjected to either an increase in left ventricular volume (VV, +25%) or an increase in coronary flow (CF, +50%), or inotropic stimulation with isoproterenol (10(-8) and 10(-6) m). The increase in VV (the Frank-Starling mechanism) increased rate-pressure product (RPP) by 21 +/- 2% under control conditions, but only by 6 +/- 2% during oxfenicine-induced CPT-I inhibition. The contractile response to changes in VV recovered after the addition of hexanoate. Similar results were obtained in hearts, in which an increase in CF was elicited (the Gregg phenomenon). Isoproterenol caused a similar increase in contractility regardless of the presence of oxfenicine or hexanoate. In all groups, a commensurate increase in oxygen consumption accompanied the increase in contractility. The fatty acid oxidation is necessary for an adequate contractile response of the isolated heart to increased pre-load or flow, whereas the inotropic response to adrenergic beta-receptor stimulation is insensitive to changes in substrate availability.

  1. Critical heart disease and mechanical circulatory support%重症心脏与心脏机械辅助装置:现状与未来

    Institute of Scientific and Technical Information of China (English)

    孙仁华; 刘景全

    2016-01-01

    机械循环支持(mechanical circulatory support,MCS)已广泛应用于ICU心源性休克及重度心力衰竭患者的救治,为心脏功能恢复的过渡发挥着重要的作用,可纠正患者的血流动力学状态,保障组织灌注,提高生存率。目前,对于MCS应用于重症心脏领域仍有很多值得进一步探索问题,如MCS适应证、应用时机及应用效果等,有待大规模临床研究验证。近年来MCS领域取得了令人欣喜的进步,如小型便携式心脏泵。未来MCS发展方向是体积小、微创、置入和撤离方便、组织相容性好及辅助效果确切。%Mechanical circulatory support (MCS) plays an important role in the treatment of cardiogenic shock and heart failure in the ICU. It is able to correct hemodynamic disorders, improve tissue perfusion and increase survival rate. But problems exist in the application of MCS in patients with critical heart disease including its indications, timing and effect, and RCTs are needed. Remarkable achievements have been made in MCS such as the application of small, portable heart pump. In future, MCS would be smaller, minimally invasive, convenient for placement and removal, and have better histocompatibility and auxiliary effectiveness.

  2. Imidazoline receptors in the heart: a novel target and a novel mechanism of action that involves atrial natriuretic peptides

    Directory of Open Access Journals (Sweden)

    S. Mukaddam-Daher

    2004-08-01

    Full Text Available Chronic stimulation of sympathetic nervous activity contributes to the development and maintenance of hypertension, leading to left ventricular hypertrophy (LVH, arrhythmias and cardiac death. Moxonidine, an imidazoline antihypertensive compound that preferentially activates imidazoline receptors in brainstem rostroventrolateral medulla, suppresses sympathetic activation and reverses LVH. We have identified imidazoline receptors in the heart atria and ventricles, and shown that atrial I1-receptors are up-regulated in spontaneously hypertensive rats (SHR, and ventricular I1-receptors are up-regulated in hamster and human heart failure. Furthermore, cardiac I1-receptor binding decreased after chronic in vivo exposure to moxonidine. These studies implied that cardiac I1-receptors are involved in cardiovascular regulation. The presence of I1-receptors in the heart, the primary site of production of natriuretic peptides, atrial natriuretic peptide (ANP and brain natriuretic peptide (BNP, cardiac hormones implicated in blood pressure control and cardioprotection, led us to propose that ANP may be involved in the actions of moxonidine. In fact, acute iv administration of moxonidine (50 to 150 µg/rat dose-dependently decreased blood pressure, stimulated diuresis and natriuresis and increased plasma ANP and its second messenger, cGMP. Chronic SHR treatment with moxonidine (0, 60 and 120 µg kg-1 h-1, sc for 4 weeks dose-dependently decreased blood pressure, resulted in reversal of LVH and decreased ventricular interleukin 1ß concentration after 4 weeks of treatment. These effects were associated with a further increase in already elevated ANP and BNP synthesis and release (after 1 week, and normalization by 4 weeks. In conclusion, cardiac imidazoline receptors and natriuretic peptides may be involved in the acute and chronic effects of moxonidine.

  3. Combined heart-kidney transplantation after total artificial heart insertion.

    Science.gov (United States)

    Ruzza, A; Czer, L S C; Ihnken, K A; Sasevich, M; Trento, A; Ramzy, D; Esmailian, F; Moriguchi, J; Kobashigawa, J; Arabia, F

    2015-01-01

    We present the first single-center report of 2 consecutive cases of combined heart and kidney transplantation after insertion of a total artificial heart (TAH). Both patients had advanced heart failure and developed dialysis-dependent renal failure after implantation of the TAH. The 2 patients underwent successful heart and kidney transplantation, with restoration of normal heart and kidney function. On the basis of this limited experience, we consider TAH a safe and feasible option for bridging carefully selected patients with heart and kidney failure to combined heart and kidney transplantation. Recent FDA approval of the Freedom driver may allow outpatient management at substantial cost savings. The TAH, by virtue of its capability of providing pulsatile flow at 6 to 10 L/min, may be the mechanical circulatory support device most likely to recover patients with marginal renal function and advanced heart failure.

  4. Heart Failure

    Science.gov (United States)

    ... heart failure due to systolic dysfunction. http://www.uptodate.com/home. Accessed Sept. 26, 2014. Colucci WS. ... patient with heart failure or cardiomyopathy. http://www.uptodate.com/home. Accessed Sept. 26, 2014. Colucci WS. ...

  5. Heart palpitations

    Science.gov (United States)

    ... Mann DL, Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine . 10th ... Mann DL, Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of ...

  6. Heart pacemaker

    Science.gov (United States)

    ... Mann DL, Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine . 10th ... Mann DL, Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of ...

  7. Heart Attack

    Science.gov (United States)

    ... a million people in the U.S. have a heart attack. About half of them die. Many people have permanent heart damage or die because they don't get ... It's important to know the symptoms of a heart attack and call 9-1-1 if someone ...

  8. Heart Truth

    Science.gov (United States)

    ... Public » Educational Campaigns & Programs » The Heart Truth Español Home About The Heart Truth ® Program Background The Red Dress ® All of Our Stories Are Red The Heart Truth ® Founding Ambassador Founding Ambassador Photographs Program Launch Program ...

  9. Could vitamin D supplements be a new therapy for heart failure? Possible pathogenic mechanisms from data of intervention studies.

    Science.gov (United States)

    Dalbeni, Andrea; Delva, Pietro; Minuz, Pietro

    2014-10-01

    Vitamin D deficiency may play a role in the pathogenesis of chronic heart failure (HF), but whether giving patients supplements to raise vitamin D into the normal range improves their survival is not clear. It has been demonstrated that vitamin D deficiency is common in patients with HF, especially the elderly, in obese and in dark skinned people, and that low vitamin D levels are associated with adverse outcome. The epidemiological data have been confirmed by experimental data, which show that knockout mice for the vitamin D receptor developed myocardial hypertrophy and dysfunction. Data from interventional studies are scarce and discordant, and more research is urgently needed to confirm whether add-on supplementation therapy with vitamin D has a role in the management of patients with chronic HF.

  10. Exercise intolerance in patients with heart failure and preserved left ventricular systolic function: failure of the Frank-Starling mechanism.

    Science.gov (United States)

    Kitzman, D W; Higginbotham, M B; Cobb, F R; Sheikh, K H; Sullivan, M J

    1991-04-01

    Invasive cardiopulmonary exercise testing was performed in 7 patients who presented with congestive heart failure, normal left ventricular ejection fraction and no significant coronary or valvular heart disease and in 10 age-matched normal subjects. Compared with the normal subjects, patients demonstrates severe exercise intolerance with a 48% reduction in peak oxygen consumption (11.6 +/- 4.0 versus 22.7 +/- 6.1 ml/kg per min; p less than 0.001), primarily due to a 41% reduction in peak cardiac index (4.2 +/- 1.4 versus 7.1 +/- 1.1 liters/min per m2; p less than 0.001). In patients compared with normal subjects, peak left ventricular stroke volume index (34 +/- 9 versus 46 +/- 7 ml/min per m2; p less than 0.01) and end-diastolic volume index (56 +/- 14 versus 68 +/- 12 ml/min per m2; p less than 0.08) were reduced, whereas peak ejection fraction and end-systolic volume index were not different. In patients, the change in end-diastolic volume index during exercise correlated strongly with the change in stroke volume index (r = 0.97; p less than 0.0001) and cardiac index (r = 0.80; p less than 0.03). Pulmonary wedge pressure was markedly increased at peak exercise in patients compared with normal subjects (25.7 +/- 9.1 versus 7.1 +/- 4.4 mm Hg; p less than 0.0001). Patients demonstrated a shift of the left ventricular end-diastolic pressure-volume relation upward and to the left at rest. Increases in left ventricular filling pressure during exercise were not accompanied by increases in end-diastolic volume, indicating a limitation to left ventricular filling.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Effects of temperature on the nitric oxide-dependent modulation of the Frank-Starling mechanism: the fish heart as a case study.

    Science.gov (United States)

    Amelio, D; Garofalo, F; Capria, C; Tota, B; Imbrogno, S

    2013-02-01

    The Frank-Starling law is a fundamental property of the vertebrate myocardium which allows, when the end-diastolic volume increases, that the consequent stretch of the myocardial fibers generates a more forceful contraction. It has been shown that in the eel (Anguilla anguilla) heart, nitric oxide (NO) exerts a direct myocardial relaxant effect, increasing the sensitivity of the Frank-Starling response (Garofalo et al., 2009). With the use of isolated working heart preparations, this study investigated the relationship between NO modulation of Frank-Starling response and temperature challenges in the eel. The results showed that while, in long-term acclimated fish (spring animals perfused at 20 °C and winter animals perfused at 10 °C) the inhibition of NO production by L-N5 (1-iminoethyl)ornithine (L-NIO) significantly reduced the Frank-Starling response, under thermal shock conditions (spring animals perfused at 10 or 15 °C and winter animals perfused at 15 or 20 °C) L-NIO treatment resulted without effect. Western blotting analysis revealed a decrease of peNOS and pAkt expressions in samples subjected to thermal shock. Moreover, an increase in Hsp90 protein levels was observed under heat thermal stress. Together, these data suggest that the NO synthase/NO-dependent modulation of the Frank-Starling mechanism in fish is sensitive to thermal stress.

  12. The effect of foot reflexology on physiologic parameters and mechanical ventilation weaning time in patients undergoing open-heart surgery: A clinical trial study.

    Science.gov (United States)

    Ebadi, Abbas; Kavei, Parastoo; Moradian, Seyyed Tayyeb; Saeid, Yaser

    2015-08-01

    The aim of this study was to investigate the efficacy of foot reflexology on physiological parameters and mechanical ventilation weaning time in patients undergoing open-heart surgery. This was a double blind three-group randomized controlled trial. Totally, 96 patients were recruited and randomly allocated to the experimental, placebo, and the control groups. Study groups respectively received foot reflexology, simple surface touching, and the routine care of the study setting. Physiological parameters (pulse rate, respiratory rate, systolic and diastolic blood pressures, mean arterial pressure, percutaneous oxygen saturation) and weaning time were measured. The study groups did not differ significantly in terms of physiological parameters (P value > 0.05). However, the length of weaning time in the experimental group was significantly shorter than the placebo and the control groups (P value reflexology in shortening the length of weaning time.

  13. The imbalance between oxygen demand and supply as a potential mechanism in the pathophysiology of heart failure : The role of microvascular growth and abnormalities

    NARCIS (Netherlands)

    De Boer, RA; Pinto, YM; van Veldhuisen, DJ

    2003-01-01

    In heart failure., a deficient oxygen supply often is a primary cause for myocardial dysfunction. The reverse however, may also be true; the changes that occur in the failing heart may predispose for the existence of tissue hypoxia, which further affects the function of the heart. Specifically, myoc

  14. Airway Complications of Total Artificial Heart.

    Science.gov (United States)

    Pathak, Vikas; Donovan, Colin; Malhotra, Rajiv

    2017-02-01

    The total artificial heart is the mechanical device which is used as a bridge to the heart transplant in patients with biventricular failure. Due to the mechanical nature of the device, patients receiving total artificial heart (TAH) require to be on anticoagulation therapy. Hemorrhage and coagulopathy are few of the known complications of TAH.

  15. Pediatric heart surgery

    Science.gov (United States)

    Heart surgery - pediatric; Heart surgery for children; Acquired heart disease; Heart valve surgery - children ... outside the heart. Some heart defects may need surgery right after the baby is born. For others, ...

  16. Hypoplastic left heart syndrome

    Science.gov (United States)

    HLHS; Congenital heart - hypoplastic left heart; Cyanotic heart disease - hypoplastic left heart ... Hypoplastic left heart is a rare type of congenital heart disease. It is more common in males than in ...

  17. Lungs in Heart Failure

    Directory of Open Access Journals (Sweden)

    Anna Apostolo

    2012-01-01

    Full Text Available Lung function abnormalities both at rest and during exercise are frequently observed in patients with chronic heart failure, also in the absence of respiratory disease. Alterations of respiratory mechanics and of gas exchange capacity are strictly related to heart failure. Severe heart failure patients often show a restrictive respiratory pattern, secondary to heart enlargement and increased lung fluids, and impairment of alveolar-capillary gas diffusion, mainly due to an increased resistance to molecular diffusion across the alveolar capillary membrane. Reduced gas diffusion contributes to exercise intolerance and to a worse prognosis. Cardiopulmonary exercise test is considered the “gold standard” when studying the cardiovascular, pulmonary, and metabolic adaptations to exercise in cardiac patients. During exercise, hyperventilation and consequent reduction of ventilation efficiency are often observed in heart failure patients, resulting in an increased slope of ventilation/carbon dioxide (VE/VCO2 relationship. Ventilatory efficiency is as strong prognostic and an important stratification marker. This paper describes the pulmonary abnormalities at rest and during exercise in the patients with heart failure, highlighting the principal diagnostic tools for evaluation of lungs function, the possible pharmacological interventions, and the parameters that could be useful in prognostic assessment of heart failure patients.

  18. Mechanical ventilation and the total artificial heart: optimal ventilator trigger to avoid post-operative autocycling - a case series and literature review

    Directory of Open Access Journals (Sweden)

    Arabia Francisco A

    2010-05-01

    Full Text Available Abstract Many patients with end-stage cardiomyopathy are now being implanted with Total Artificial Hearts (TAHs. We have observed individual cases of post-operative mechanical ventilator autocycling with a flow trigger, and subsequent loss of autocycling after switching to a pressure trigger. These observations prompted us to do a retrospective review of all TAH devices placed at our institution between August 2007 and May 2009. We found that in the immediate post-operative period following TAH placement, autocycling was present in 50% (5/10 of cases. There was immediate cessation of autocycling in all patients after being changed from a flow trigger of 2 L/minute to a pressure trigger of 2 cm H2O. The autocycling group was found to have significantly higher CVP values than the non-autocycling group (P = 0.012. Our data suggest that mechanical ventilator autocycling may be resolved or prevented by the use of a pressure trigger rather than a flow trigger setting in patients with TAHs who require mechanical ventilation.

  19. Heart attack

    Science.gov (United States)

    ... Saunders; 2014:chap 51. Read More Arrhythmias Cardiogenic shock Diabetes Hardening of the arteries Heart failure - overview High blood pressure Implantable cardioverter-defibrillator Lipoprotein- ...

  20. Mechanical Circulatory Support Devices Improve Tissue Perfusion in Patients With End-Stage Heart Failure or Cardiogenic Shock

    NARCIS (Netherlands)

    C.A. den Uil; A.P. Maat; W.K. Lagrand; M. van der Ent; L.S.D. Jewbali; R.J. van Thiel; P.E. Spronk; M.L. Simoons

    2009-01-01

    Objectives: This study evaluated the effects of mechanical circulatory support (MCS) on sub-lingual microcirculation as a surrogate for splanchnic microvascular perfusion. Methods: Between May 2008 and April 2009, 10 consecutive patients received an MCS device or extracorporeal membrane oxygenation

  1. Pulmonary valve replacement with a mechanical prosthesis. Promising results of 28 procedures in patients with congenital heart disease

    NARCIS (Netherlands)

    Hoendermis, Elke S.; den Hamer, Inez J.; Ebels, Tjark; Waterbolk, T

    2006-01-01

    Objective: Pulmonary valve replacement is performed increasingly late after correction of Tetralogy of Fallot. Most reports deal with pulmonary allografts as the valvar substitute of choice, although late deterioration and reoperation(s) are the rule. Mechanical valves are scarcely reported and if s

  2. Advanced echocardiography and cardiac magnetic resonance in congenital heart disease : insights in right ventricular mechanics and clinical implications

    NARCIS (Netherlands)

    Hulst, Anna Elisabeth van der

    2011-01-01

    The thesis provides new insights into advanced echocardiographic and magnetic resonance imaging techniques for comprehensive mechanical assessment of the right ventricle in healthy children and in pediatric patients with right ventricular dysfunction. It is shown that the right ventricle does not co

  3. Depression and Coronary Heart Disease

    OpenAIRE

    2012-01-01

    There are exciting findings in the field of depression and coronary heart disease. Whether diagnosed or simply self-reported, depression continues to mark very high risk for a recurrent acute coronary syndrome or for death in patients with coronary heart disease. Many intriguing mechanisms have been posited to be implicated in the association between depression and heart disease, and randomized controlled trials of depression treatment are beginning to delineate the types of depression manage...

  4. Heart failure

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    970284 Effects of enalapril on heart rate variabilityin patients with congestive heart failure. ZHANGYouhua(章友华), et a1. Dept Cardiol, Cardiovasc Instit& Fuwai Hosp, CAMS & PUMC, Beijing, 100037. ChinCir J 1996; 11(2): 729-732.

  5. Heart transplant

    Science.gov (United States)

    ... factors include the type and severity of your heart disease, and how sick you are at the time you are listed. The amount of time you spend on a waiting list is usually NOT a factor for how soon you get a heart, except in the case of children. Most, but ...

  6. Heart Anatomy

    Science.gov (United States)

    ... from the left ventricle into the aorta, your body's largest artery. See also on this site: The Heartbeat The Conduction System (illustration) Electrical impulses from your heart muscle (the myocardium) cause your heart to contract. This electrical signal begins in the sinoatrial (SA) node, located at ...

  7. [Mechanobiology and the Heart].

    Science.gov (United States)

    Ishiguro, Yoshiki

    2016-05-01

    Mechanobiology has been focusing on biological research regarding mechanisms of muscle force generation, or recently sensing and response to the force applied to the tissue or each cell. Therefore, the heart has been one of the target organs and studied extensively for a long time since late 19th century. Its force-length relationship was demonstrated as the Starling's law of the heart, which is one of the most important findings in mechanobiology. In late 20th century, excitation-contraction coupling in the muscle was demonstrated and then, molecular mechanisms are gradually elucidated including calcium homeostasis and signal transductions in various situations: under the effects of catecholamines, other vasoactive agents, or ischemia. Among them, recent findings suggest possible involvement of titin, the giant elastic protein connected with both actin and myosin, with basic mechanism of the Starling's law of the heart Pathological proliferation of the heart as hypertrophic remodeling has also been extensively studied in recent years, and its signal transduction from pressure overload and volume overload to respective morphological changes of the heart chamber are partially clarified.

  8. The mechanism of neurally mediated syncope assessed by an ambulatory radionuclide monitoring system and heart rate variability indices during head-up tilt

    Energy Technology Data Exchange (ETDEWEB)

    Hosaka, Haruhiko [Self Defense Force Central Hospital, Tokyo (Japan); Takase, Bonpei; Ohsuzu, Fumitaka [National Defense Medical Coll., Tokorozawa, Saitama (Japan); Kurita, Akira [National Defense Medical Coll., Tokorozawa, Saitama (Japan). Research Center

    2002-11-01

    Previously, we tested the hypothesis that the great decline in left ventricular volume during head-up tilt test could trigger ventricular mechanoreceptor activation, using ambulatory radionuclide monitoring system (C-VEST system). The aim of this study is to investigate the mechanism of tilt-induced syncope further, based on our previous report. We measured the temporal changes in left ventricular volume, ejection fraction, cardiac output, and heart rate variability indices during head-up tilt test in 34 patients with syncope of an undetermined etiology. Twenty-two patients and a positive response (P group). Twelve patients showed a negative response (N group). Before syncope, left ventricular volume declined (P group, diastolic volume; -7.9{+-}6.8%: systolic volume; -23.3{+-}33.8%: N group, diastolic volume; -2.5{+-}1.9%: systolic volume; 0.6{+-}9.5%: p<0.05), ejection fraction increased (P group, 3.9{+-}2.5%; N group, -3.5{+-}7.2%; p<0.005), and high frequency spectra increased (P group, 12.0{+-}20.3%; N group, 3.1{+-}9.7%; p<0.05), more extremely in the P group than in the N group. The value of the high frequency spectra before the head-up tilt test was significantly higher in the P group than in the N group (P group, 5.8{+-}0.9 ms; N group, 5.0{+-}1.1 ms; p<0.05). The precise evaluation of left ventricular volume by ambulatory radionuclide monitoring system combined with a heart rate variability analysis is considered to be useful for clarifying the pathophysiology of neurally mediated syncope. Patients with neurally mediated syncope have higher baseline parasympathetic tone than normal population. (author)

  9. Actualización en los mecanismos fisiopatológicos de la insuficiencia cardiaca Update in physiopathological mechanisms in heart failure

    Directory of Open Access Journals (Sweden)

    Guido Ulate-Montero

    2008-03-01

    fibrosis y de arritmias cardiacas, para lo cual es indispensable el manejo apropiado de los niveles intracelulares de Ca2+.Heart failure is one of the most frequent clinical syndromes in medical practice;it appears when the heart is unable to pump enough volume of blood to supply the tissue ’s requirements.This article reviews the most recent information regarding the mechanisms involved in the pathophysiology of heart failure,the main goal is to offer the knowledge necessary to understand and manage properly this condition.In heart failure,as a response to the low cardiac output,a series of neuroendocrine systemic mechanisms are activated,but they contribute to deteriorate the clinical status;this happens with the sympathetic and the renin-angiotensin-aldosterone systems,which end up producing endothelial damage,increase of oxidative radicals,apoptosis, cardiac fibrosis and generation of arrhythmias.Also there is an increase in the secretion of natriuretic peptides,which tend to regulate some of the exacerbated neuroendocrine responses, but with time their effect tend to diminish.At the cellular and molecular level a series of alterations occur in the regulation of intracellular Ca2+, as well as in some of the ionic currents that play a role in the generation of action potentials in cardiac myocytes.Cardiac remodeling precedes the clinical manifestations of heart failure and contributes to its deterioration.Chemical messengers like endothelin-1,norepinephrine and angiotensin II,activate the MAP kinases cascade and provoke cardiac hypertrophy favoring the development of ischemia and the appearance of arrhythmias.Pharmacological management of heart failure must aim the mechanisms affected,it must block the deleterious actions of the neuroendocrine systems,avoiding the loss of myocytes, the generation of fibrosis and the production of cardiac arrhythmias,in order to achieve this goal an appropriate management of intracellular levels of Ca2+ is required.

  10. Cardiomyocytic apoptosis and heart failure

    Institute of Scientific and Technical Information of China (English)

    Quanzhou Feng

    2008-01-01

    Heart failure is a major disease seriously threatening human health.Once left ventricular dysfunction develops,cardiac function usually deteriorates and progresses to congestive heart failure in several months or years even if no factors which accelerate the deterioration repeatedly exist.Mechanism through which cardiac function continually deteriorates is still unclear.Cardiomyocytic apoptosis can occur in acute stage of ischemic heart diseases and the compensated stage of cardiac dysfunction.In this review,we summarize recent advances in understanding the role of cardiomyocytic apoptosis in heart failure.

  11. Men and Heart Disease

    Science.gov (United States)

    ... Pressure Salt Cholesterol Million Hearts® WISEWOMAN Men and Heart Disease Fact Sheet Recommend on Facebook Tweet Share Compartir ... Source: Interactive Atlas of Heart Disease and Stroke Heart Disease Facts in Men Heart disease is the leading ...

  12. How the Heart Works

    Science.gov (United States)

    ... Works Explore How the Heart Works What Is... Anatomy Contraction Circulation Electrical System Heart Disease Related Topics Arrhythmia Congenital Heart Defects Coronary Heart Disease Heart Valve Disease How the Lungs Work Send a link to NHLBI to someone ...

  13. About Heart Failure

    Science.gov (United States)

    ... talk about your health and the medicines About Heart Failure Heart failure is a disease where the heart cannot do ... very important for your health. common causes of heart failure are diseases or conditions that damage the heart. ...

  14. What Is Heart Failure?

    Science.gov (United States)

    ... page from the NHLBI on Twitter. What Is Heart Failure? Heart failure is a condition in which the heart can' ... force. Some people have both problems. The term "heart failure" doesn't mean that your heart has stopped ...

  15. Wine and heart health

    Science.gov (United States)

    Health and wine; Wine and heart disease; Preventing heart disease - wine; Preventing heart disease - alcohol ... more often just to lower your risk of heart disease. Heavier drinking can harm the heart and ...

  16. [Preparation of Ti-O Film Deposited on the Surface of a New Type of Artificial Mechanical Heart Valve].

    Science.gov (United States)

    Zhou, Feng; Cui, Yuanyuan; Wu, Liangliang; Sun, Hong; Huang, Nan

    2015-04-01

    The rutile structure titanium oxide (Ti-O) film was prepared on the pure titanium material TA2 (99.999%) surface by the magnetic filter high vacuum arc deposition sputtering source. The method can not only maintain the material mechanical properties, but also improve the surface properties for better biocompatibility to accommodate the physiological environment. The preparation process of the Ti-O film was as follows. Firstly, argon ions sputtered to the TA2 substrate surface to remove the excess impurities. Secondly, a metal ion source generated Ti ions and oxygen ions by the RF discharge. Meanwhile a certain negative bias was imposed on the sample. There a certain composition of Ti-O film was obtained under a certain pressure of oxygen in the vacuum chamber. Finally, X-ray diffraction was used to research the structure and composition of the film. The results showed that the Ti-O film of the rutile crystal structure was formed under the 0.18 Pa oxygen partial pressure. A Nano scratch experiment was used to test the coating adhesion property, which demonstrated that the film was stable and durable. The contact angle experiment and the platelet clotting experiment proved that the modified surface method had improved platelet adhesion performance, and, therefore, the material possessed better biocompatibility. On the whole, the evaluations proved the modified material had excellent performance.

  17. Heart Disease

    Science.gov (United States)

    ... Atherosclerosis is also the most common cause of cardiovascular disease. It can be caused by correctable problems, such as an unhealthy diet, lack of exercise, being overweight and smoking. Causes of heart arrhythmia ...

  18. Heart Attack

    Science.gov (United States)

    ... tear in the heart artery (spontaneous coronary artery dissection). Certain factors contribute to the unwanted buildup of ... logo are trademarks of Mayo Foundation for Medical Education and Research. © 1998-2017 Mayo Foundation for Medical ...

  19. Heart failure

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    2008275 Relationship of calcineure in mRNA level in peripheral blood and cardiac muscle of patients with heart failure.WANG Mengmeng(王萌萌),et al.Dept Cardiol,Shandong Prov Hosp,Shandong Univ,Jinan 250021.Chin Cir J 2008;23(2):113-116.Objective To study the relationship of calcineurin mRNA level between peripheral lymphocytes and cardiac muscles of patients with chronic heart failure.Methods

  20. Heart failure

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    2008037 Factors associated with efficacy of cardiac resynchronization therapy for patients with congestive heart failure. SHI Haoying(史浩颖), et al. Dept Cardiol, Zhongshan Hosp Fudan Univ, Shanghai 200032. Chin J Cardiol 2007;35(12):1099-1163. Objective The efficacy of cardiac resynchronization therapy (CRT) in patients with congestive heart failure and the potential factors associated with responder or nonresponder were investigated. Methods Fifty

  1. Studies on very long chain marine n-3 fatty acids in patients with atherosclerotic heart disease with special focus on mechanisms, dosage and formulas of supplementation.

    Science.gov (United States)

    Arnesen, H; Seljeflot, I

    2010-02-25

    Based on experience from randomised trials with n-3 PUFA we intend to answer some relevant questions in patients with coronary heart disease. In the SHOT study supplementation with 3.4 g/day of highly concentrated n-3 PUFA for 1 year significantly reduced the occlusion rate of venous aortocoronary bypass grafts, and this effect correlated significantly to the change in serum levels of n-3 fatty acids. In the CART study 5.1 g/day of highly concentrated n-3 PUFA did not reduce the incidence of restenosis after 6 months. If anything, a negative effect was observed. The background for this was probably a pro-oxidative and proinflammatory mechanism as elucidated in substudies. In the OVITES trial the addition of vitamin E did not counteract the proinflammatory effect of high amounts of n-3 PUFA supplementation as observed in CART, although circulating oxidative substances were unaffected. In the "Fiord-to-table" study replacement of fish oils by vegetable oils in the feed of farmed Atlantic salmon was mirrored in the fatty acid profile of the salmon fillets as well as in that of serum from patients after ingesting about 700 g/week for six weeks. A parallel reduction of the proinflammatory profile was observed only in patients who ingested salmon fed on fish oil.

  2. The effect of adrenaline and high Ca2+ on the mechanical performance and oxygen consumption of the isolated perfused trout (Oncorhynchus mykiss) heart

    DEFF Research Database (Denmark)

    Rytter, Dorte; Gesser, Hans

    2007-01-01

    In heart muscle from mammals, catecholamines frequently evoke an oxygen waste and reduce efficiency. It was examined if this also applies to fish in which heart muscle activity is often restricted by oxygen availability. In the isolated perfused heart from rainbow trout, adrenaline (0.5 micro......M) increased power output by approximately 97%, when afterload was adjusted to maximum both before and after adrenaline addition, and by approximately 68%, when afterload remained at the maximum obtained before adrenaline addition. Oxygen consumption was enhanced by a similar amount (approximately 70%) in both...... situations. Hence, efficiency, i.e. power output/oxygen consumption, increased significantly from 25 to 30% for the heart always exposed to maximal afterload, whereas it stayed unchanged at 24% for the heart exposed to control afterload only. Adrenaline increases the Ca2+ activity participating in activation...

  3. The Basic Mechanism of Beta-blocker in Chronic Heart Failure%β受体阻断剂在慢性心衰中作用的基础机制

    Institute of Scientific and Technical Information of China (English)

    刘伟

    2011-01-01

    心力衰竭是很多心血管疾病的最终阶段,也是常见的致死原因之一.心力衰竭时起代偿作用的交感神经系统的持续兴奋是导致心力衰竭恶化的一个重要原因.近年来,众多临床试验证实β受体阻断剂类药物对心力衰竭有良好的治疗作用,β受体阻断剂能通过慢性抑制交感神经的兴奋,改善心力衰竭患者心功能,从而减少患者病死率,增加生存率.%Heart failure is the final phase for many cardiovascular diseases , one of the common fatal causes as well. One important reason of heart failure deterioration is the sustained excitement of sympathetic nervous system which is a compensatory mechanism in heart failure. In recent years,evidence has been accumulated on the beneficial actions of beta-blockers in patients with heart failure. The effect of beta-blocker in chronic inhibition of sympathetic nervous system can improve cardiac function of heart failure patients , reduce mortality and increase survival rates.

  4. Negative impact of β-arrestin-1 on post-myocardial infarction heart failure via cardiac and adrenal-dependent neurohormonal mechanisms.

    Science.gov (United States)

    Bathgate-Siryk, Ashley; Dabul, Samalia; Pandya, Krunal; Walklett, Karlee; Rengo, Giuseppe; Cannavo, Alessandro; De Lucia, Claudio; Liccardo, Daniela; Gao, Erhe; Leosco, Dario; Koch, Walter J; Lymperopoulos, Anastasios

    2014-02-01

    β-Arrestin (βarr)-1 and β-arrestin-2 (βarrs) are universal G-protein-coupled receptor adapter proteins that negatively regulate cardiac β-adrenergic receptor (βAR) function via βAR desensitization and downregulation. In addition, they mediate G-protein-independent βAR signaling, which might be beneficial, for example, antiapoptotic, for the heart. However, the specific role(s) of each βarr isoform in cardiac βAR dysfunction, the molecular hallmark of chronic heart failure (HF), remains unknown. Furthermore, adrenal βarr1 exacerbates HF by chronically enhancing adrenal production and hence circulating levels of aldosterone and catecholamines. Herein, we sought to delineate specific roles of βarr1 in post-myocardial infarction (MI) HF by testing the effects of βarr1 genetic deletion on normal and post-MI cardiac function and morphology. We studied βarr1 knockout (βarr1KO) mice alongside wild-type controls under normal conditions and after surgical MI. Normal (sham-operated) βarr1KO mice display enhanced βAR-dependent contractility and post-MI βarr1KO mice enhanced overall cardiac function (and βAR-dependent contractility) compared with wild type. Post-MI βarr1KO mice also show increased survival and decreased cardiac infarct size, apoptosis, and adverse remodeling, as well as circulating catecholamines and aldosterone, compared with post-MI wild type. The underlying mechanisms, on one hand, improved cardiac βAR signaling and function, as evidenced by increased βAR density and procontractile signaling, via reduced cardiac βAR desensitization because of cardiac βarr1 absence, and, on the other hand, decreased production leading to lower circulating levels of catecholamines and aldosterone because of adrenal βarr1 absence. Thus, βarr1, via both cardiac and adrenal effects, is detrimental for cardiac structure and function and significantly exacerbates post-MI HF.

  5. Anemia and iron deficiency in heart failure.

    Science.gov (United States)

    Gil, Victor M; Ferreira, Jorge S

    2014-01-01

    Heart failure is a common problem and a major cause of mortality, morbidity and impaired quality of life. Anemia is a frequent comorbidity in heart failure and further worsens prognosis and disability. Regardless of anemia status, iron deficiency is a common and usually unidentified problem in patients with heart failure. This article reviews the mechanisms, impact on outcomes and treatment of anemia and iron deficiency in patients with heart failure.

  6. Computer Simulation of the Beating Human Heart

    Science.gov (United States)

    Peskin, Charles S.; McQueen, David M.

    2001-06-01

    The mechanical function of the human heart couples together the fluid mechanics of blood and the soft tissue mechanics of the muscular heart walls and flexible heart valve leaflets. We discuss a unified mathematical formulation of this problem in which the soft tissue looks like a specialized part of the fluid in which additional forces are applied. This leads to a computational scheme known as the Immersed Boundary (IB) method for solving the coupled equations of motion of the whole system. The IB method is used to construct a three-dimensional Virtual Heart, including representations of all four chambers of the heart and all four valves, in addition to the large arteries and veins that connect the heart to the rest of the circulation. The chambers, valves, and vessels are all modeled as collections of elastic (and where appropriate, actively contractile) fibers immersed in viscous incompressible fluid. Results are shown as a computer-generated video animation of the beating heart.

  7. Nerves Regulate Cardiomyocyte Proliferation and Heart Regeneration.

    Science.gov (United States)

    Mahmoud, Ahmed I; O'Meara, Caitlin C; Gemberling, Matthew; Zhao, Long; Bryant, Donald M; Zheng, Ruimao; Gannon, Joseph B; Cai, Lei; Choi, Wen-Yee; Egnaczyk, Gregory F; Burns, Caroline E; Burns, C Geoffrey; MacRae, Calum A; Poss, Kenneth D; Lee, Richard T

    2015-08-24

    Some organisms, such as adult zebrafish and newborn mice, have the capacity to regenerate heart tissue following injury. Unraveling the mechanisms of heart regeneration is fundamental to understanding why regeneration fails in adult humans. Numerous studies have revealed that nerves are crucial for organ regeneration, thus we aimed to determine whether nerves guide heart regeneration. Here, we show using transgenic zebrafish that inhibition of cardiac innervation leads to reduction of myocyte proliferation following injury. Specifically, pharmacological inhibition of cholinergic nerve function reduces cardiomyocyte proliferation in the injured hearts of both zebrafish and neonatal mice. Direct mechanical denervation impairs heart regeneration in neonatal mice, which was rescued by the administration of neuregulin 1 (NRG1) and nerve growth factor (NGF) recombinant proteins. Transcriptional analysis of mechanically denervated hearts revealed a blunted inflammatory and immune response following injury. These findings demonstrate that nerve function is required for both zebrafish and mouse heart regeneration.

  8. Heart failure - tests

    Science.gov (United States)

    CHF - tests; Congestive heart failure - tests; Cardiomyopathy - tests; HF - tests ... the best test to: Identify which type of heart failure (systolic versus diastolic, valvular) Monitor your heart failure ...

  9. Problem: Heart Valve Stenosis

    Science.gov (United States)

    ... Cholesterol Tools & Resources Congenital Defects Children & Adults About Congenital Heart Defects The Impact of Congenital Heart Defects Understand Your Risk for Congenital Heart Defects Symptoms & ...

  10. Healthy Heart Quizzes

    Science.gov (United States)

    ... Cholesterol Tools & Resources Congenital Defects Children & Adults About Congenital Heart Defects The Impact of Congenital Heart Defects Understand Your Risk for Congenital Heart Defects Symptoms & ...

  11. Problem: Heart Valve Regurgitation

    Science.gov (United States)

    ... Cholesterol Tools & Resources Congenital Defects Children & Adults About Congenital Heart Defects The Impact of Congenital Heart Defects Understand Your Risk for Congenital Heart Defects Symptoms & ...

  12. Travel and Heart Disease

    Science.gov (United States)

    ... Cholesterol Tools & Resources Congenital Defects Children & Adults About Congenital Heart Defects The Impact of Congenital Heart Defects Understand Your Risk for Congenital Heart Defects Symptoms & ...

  13. Cumene hydroperoxide, an agent inducing lipid peroxidation, and 4-hydroxy-2,3-nonenal, a peroxidation product, cause coronary vasodilatation in perfused rat hearts by a cyclic nucleotide independent mechanism.

    Science.gov (United States)

    van der Kraaij, A M; de Jonge, H R; Esterbauer, H; de Vente, J; Steinbusch, H W; Koster, J F

    1990-02-01

    STUDY OBJECTIVE - The aim of the study was to determine whether cumene hydroperoxide, a substance known to induce lipid peroxidation through free radical action, and 4-hydroxy-2,3-nonenal (4-hydroxynonenal), a major aldehyde formed during lipid peroxidation, induce coronary vasodilatation by changing cyclic nucleotide levels. DESIGN - The study involved Langendorff perfused rat hearts, using different concentrations of cumene hydroperoxide and 4-hydroxynonenal, with sodium nitroprusside for comparison. Coronary flow was measured indirectly as retrograde aortic flow, with constant perfusion pressure. Information about the precise localisation of cyclic guanosine monophosphate (cGMP) in the heart was obtained by immunocytochemistry, using a new cGMP antiserum. EXPERIMENTAL MATERIAL - Hearts were from male Wistar rats, body weight 200-250 g. MEASUREMENTS and RESULTS - Both cumene hydroperoxide and 4-hydroxynonenal caused a dose dependent and reversible increase in coronary flow comparable with sodium nitroprusside. With sodium nitroprusside there was a good correlation between extent of vasodilatation and total heart cGMP concentration. Vasodilatation induced by cumene hydroperoxide or 4-hydroxynonenal was not accompanied by increase in total heart cGMP or cAMP (cyclic adenosine monophosphate) concentration. Isoprenaline was used as a positive control for cAMP. cGMP immunostaining was found in coronary vascular smooth muscle after vasodilatation with sodium nitroprusside, but no immunostaining was found in vascular smooth muscle after vasodilatation with cumene hydroperoxide or 4-hydroxynonenal. CONCLUSIONS - Cumene hydroperoxide and 4-hydroxynonenal can provoke reversible coronary vasodilatation in isolated perfused rat hearts by a cyclic nucleotide independent mechanism.

  14. Incidence of thromboembolic complications in patients with atrial fibrillation or mechanical heart valves with a subtherapeutic international normalized ratio: a prospective multicenter cohort study.

    Science.gov (United States)

    Dentali, Francesco; Pignatelli, Pasquale; Malato, Alessandra; Poli, Daniela; Di Minno, Matteo Nicola Dario; Di Gennaro, Leonardo; Rancan, Elena; Pastori, Daniele; Grifoni, Elisa; Grifoni, Elena; Squizzato, Alessandro; Siragusa, Sergio; Di Minno, Giovanni; Ageno, Walter

    2012-04-01

    Subtherapeutic international normalized ratio (INR) is frequently encountered in clinical practice, and patients with high-risk atrial fibrillation (AF) and with mechanical heart valve (MHV) with inadequate anticoagulation may be exposed to an increased risk of thromboembolic events (TE). However, there are no prospective data evaluating this risk. Consecutive patients with a history of stable anticoagulation, but with a subtherapeutic INR, were prospectively included. Data on use and dose of low-molecular weight heparin (LMWH) bridging therapy were collected. The incidence of objectively confirmed TE and of major bleeding events within 90 days after the index INR was assessed. Five hundred and one patients with INR value 0.5-1 INR units below the lower limit of the patient-specific target INR were included in the study (280 with MHV and 221 with AF and CHADS2 score ≥3). LMWH was prescribed for 64 patients (12.8%). During follow-up, seven patients had a TE (1.40%; 95% confidence interval 0.68, 2.86%; 5.58 events for 100 patients year). All the events occurred within 14 days after the index INR. When we consider only patients who did not receive bridging therapy, the incidence of TE was 1.14% (5 of 437 patients; 95% confidence interval 0.49, 2.64%; 4.58 events for 100 patients year). There were no major bleeding events. The risk of TE in this population was not negligible. Given the frequent observation of subtherapeutic INR levels when monitoring vitamin K antagonists, this finding warrants additional investigation to improve the management of these patients.

  15. From basic mechanisms to clinical applications in heart protection, new players in cardiovascular diseases and cardiac theranostics:meeting report from the third international symposium on "New frontiers in cardiovascular research"

    OpenAIRE

    Cabrera-Fuentes, Hector A.; Aragones, Julian; Bernhagen, Jürgen; Boening, Andreas; William A. Boisvert; Bøtker, Hans E.; Bulluck, Heerajnarain; Cook, Stuart; Di Lisa, Fabio; Engel, Felix B.; Engelmann, Bernd; Ferrazzi, Fulvia; Ferdinandy, Péter; Fong, Alan; Fleming, Ingrid

    2016-01-01

    In this meeting report, particularly addressing the topic of protection of the cardiovascular system from ischemia/reperfusion injury, highlights are presented that relate to conditioning strategies of the heart with respect to molecular mechanisms and outcome in patients' cohorts, the influence of co-morbidities and medications, as well as the contribution of innate immune reactions in cardioprotection. Moreover, developmental or systems biology approaches bear great potential in systematica...

  16. Women's Heart Disease: Heart Disease Risk Factors

    Science.gov (United States)

    ... this page please turn JavaScript on. Feature: Women's Heart Disease Heart Disease Risk Factors Past Issues / Winter 2014 Table of ... or habits may raise your risk for coronary heart disease (CHD). These conditions are known as risk factors. ...

  17. Women's Heart Disease: Heart Attack Symptoms

    Science.gov (United States)

    ... this page please turn JavaScript on. Feature: Women's Heart Disease Heart Attack Symptoms Past Issues / Winter 2014 Table ... NHLBI has uncovered some of the causes of heart diseases and conditions, as well as ways to prevent ...

  18. Heart Health: The Heart Truth Campaign 2009

    Science.gov (United States)

    ... Past Issues Cover Story Heart Health The Heart Truth Campaign 2009 Past Issues / Winter 2009 Table of ... of the celebrities supporting this year's The Heart Truth campaign. Both R&B singer Ashanti (center) and ...

  19. Heart failure

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    2009170 Curcumin attenuates left ventricular dysfunction and remodeling in rabbits with chronic heart failure. TANG Yanhong(唐艳红),et al.Dept Cardiol,Renmin Hosp,Wuhan Univ,Wuhan 430060.Chin J Cardiol,2009;37(3):262-267.

  20. Heart failure

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    2008411 Expression of S100B during heart failure in rats. JIANG Zhenni(蒋珍妮), et al. Dept Cardiol, 2nd Affili Hosp, Zhejiang Univ, Coll Med Hangzhou 310009. Chin J Emerg Med 2008;17(5):475-478. Objective To evaluate the value of S100B gene on cardiovascular remodeling in rats with abdominal aorta coarctation.

  1. Signaling and transcriptional networks in heart development and regeneration.

    Science.gov (United States)

    Bruneau, Benoit G

    2013-03-01

    The mammalian heart is the first functional organ, the first indicator of life. Its normal formation and function are essential for fetal life. Defects in heart formation lead to congenital heart defects, underscoring the finesse with which the heart is assembled. Understanding the regulatory networks controlling heart development have led to significant insights into its lineage origins and morphogenesis and illuminated important aspects of mammalian embryology, while providing insights into human congenital heart disease. The mammalian heart has very little regenerative potential, and thus, any damage to the heart is life threatening and permanent. Knowledge of the developing heart is important for effective strategies of cardiac regeneration, providing new hope for future treatments for heart disease. Although we still have an incomplete picture of the mechanisms controlling development of the mammalian heart, our current knowledge has important implications for embryology and better understanding of human heart disease.

  2. Coronary heart disease

    Science.gov (United States)

    Heart disease, Coronary heart disease, Coronary artery disease; Arteriosclerotic heart disease; CHD; CAD ... slow down or stop. A risk factor for heart disease is something that increases your chance of getting ...

  3. Diabetic Heart Disease

    Science.gov (United States)

    ... be coronary heart disease (CHD), heart failure, and diabetic cardiomyopathy. Diabetes by itself puts you at risk for heart disease. Other risk factors include Family history of heart disease Carrying extra ...

  4. Classes of Heart Failure

    Science.gov (United States)

    ... Disease Venous Thromboembolism Aortic Aneurysm More Classes of Heart Failure Updated:Sep 28,2016 Doctors usually classify patients' ... Blood Pressure Tracker Find additional helpful resources here Heart Failure • Home • About Heart Failure Introduction Types of Heart ...

  5. Heart attack first aid

    Science.gov (United States)

    First aid - heart attack; First aid - cardiopulmonary arrest; First aid - cardiac arrest ... A heart attack occurs when the blood flow that carries oxygen to the heart is blocked. The heart muscle ...

  6. Prosthetic heart valve assessment with multidetector-row CT: imaging characteristics of 91 valves in 83 patients

    Energy Technology Data Exchange (ETDEWEB)

    Habets, Jesse; Mali, Willem P.T.M.; Budde, Ricardo P.J. [UMC Utrecht, Department of Radiology, P.O. Box 85500, E01.132, GA, Utrecht (Netherlands); Symersky, Petr [Onze Lieve Vrouwe Gasthuis, Department of Cardiothoracic Surgery, Amsterdam (Netherlands); Academic Medical Center Amsterdam, Department of Cardiothoracic Surgery, Amsterdam (Netherlands); Herwerden, Lex A. van [University Medical Center Utrecht, Department of Cardiothoracic Surgery, Utrecht (Netherlands); Mol, Bas A.J.M. de [Academic Medical Center Amsterdam, Department of Cardiothoracic Surgery, Amsterdam (Netherlands); Spijkerboer, Anje M. [Academic Medical Center Amsterdam, Department of Radiology, Amsterdam (Netherlands)

    2011-07-15

    Multidetector CT (MDCT) has shown potential for prosthetic heart valve (PHV) assessment. We assessed the image quality of different PHV types to determine which valves are suitable for MDCT evaluation. All ECG-gated CTs performed in our institutions since 2003 were reviewed for the presence of PHVs. After reconstruction in 3 specific PHV planes, image quality of the supravalvular, perivalvular, subvalvular and valvular regions was scored on a four-point scale (1 = non-diagnostic, 2 = moderate, 3 = good and 4 = excellent) by two independent observers. Eighty-four CT examinations (66 cardiac, 18 limited-dose aortic protocols) of 83 patients with a total of 91 PHVs in the aortic (n = 71), mitral (n = 17), pulmonary (n = 1) and tricuspid (n = 2) position were included. CT was performed on a 16-slice (n = 4), 64-slice (n = 28) or 256-slice (n = 52) MDCT system. Median image quality scores for the supra-, peri- and subvalvular regions and valvular detail were (3.5, 3.3, 3.5 and 3.5, respectively) for bileaflet PHV; (3.0, 3.0, 3.5 and 3.0, respectively) for Medtronic Hall PHV; (1.0, 1.0, 1.0 and 1.0, respectively) for Bjoerk-Shiley and Sorin monoleaflet PHV and (3.5, 3.5, 4.0 and 2.0 respectively) for biological PHV. Currently implanted PHVs have good image quality on MDCT and are suitable for MDCT evaluation. (orig.)

  7. Heart failure

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    2005186 The diagnostic application of bedside measurement of plasma brain natriuretic in patients with heart failure. SHAO Le-wen (邵乐文) , Advanced Ward Dept, 1st Hosp, Med Sch, Zhejiang Univ, Hangzhou 310003. Chin J Intern Med, 2005;44(2): 99-101. Objective: To investigate differential diagnosis value of ultra-rapid bedside measurement of brain na-triuretic peptide (BNP) in patients with dyspnea.

  8. Heart failure

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    2010316 Tissue doppler imaging observation on effect of long-term use of gingko biloba tabtet on left ventricular function in patients with chronic heart failure. ZHANG Hui(张辉),et al. Dept Cardiovasc Med, 2nd Hosp, Hebei Med Univ,Shijiazhuang 050000. Chin J Integr Tradit & West Med 2010;30(5):478-481. Objective To quantitatively observe the effect of long-term

  9. Cardiac mechanics and ventricular twist by three-dimensional strain analysis in relation to B-type natriuretic peptide as a clinical prognosticator for heart failure patients.

    Directory of Open Access Journals (Sweden)

    Sheng-Nan Chang

    Full Text Available BACKGROUND: Three dimensional (3D echocardiography-derived measurements of myocardial deformation and twist have recently advanced as novel clinical tools. However, with the exception of left ventricular ejection fraction and mass quantifications in hypertension and heart failure populations, the prognostic value of such imaging techniques remains largely unexplored. METHODS: We studied 200 subjects (mean age: 60.2±16 years, 54% female, female n = 107 with known hypertension (n = 51, diastolic heart failure (n = 61, or systolic heart failure (n = 30, recruited from heart failure outpatient clinics. Fifty-eight healthy volunteers were used as a control group. All participants underwent 3D-based myocardial deformation and twist analysis (Artida, Toshiba Medical Systems, Tokyo, Japan. We further investigated associations between these measures and brain natriuretic peptide levels and clinical outcomes. RESULTS: The global 3D strain measurements of the healthy, hypertension, diastolic heart failure, and systolic heart failure groups were 28.03%, 24.43%, 19.70%, and 11.95%, respectively (all p<0.001. Global twist measurements were estimated to be 9.49°, 9.77°, 8.32°, and 4.56°, respectively. We observed significant differences regarding 3D-derived longitudinal, radial, and global 3D strains between the different disease categories (p<0.05, even when age, gender, BMI and heart rate were matched. In addition, 3D-derived longitudinal, circumferential, and 3D strains were all highly correlated with brain natriuretic peptide levels (p<0.001. At a mean 567.7 days follow-up (25th-75th IQR: 197-909 days, poorer 3D-derived longitudinal, radial, and global 3D strain measurements remained independently associated with a higher risk of cardiovascular related death or hospitalization due to heart failure, after adjusting for age, gender, and left ventricular ejection fraction (all p<0.05. CONCLUSIONS: 3D-based strain analysis may be a

  10. Ventricular assist device in univentricular heart physiology.

    Science.gov (United States)

    Brancaccio, Gianluca; Gandolfo, Fabrizio; Carotti, Adriano; Amodeo, Antonio

    2013-04-01

    The use of mechanical cardiac assistance is well established as a bridge to orthotopic heart transplantation (OHT) or to recovery for patients with congestive heart failure, however, the experience in single ventricle (SV) physiology is still limited. We report two cases of mechanical assistance in patients with SV physiology: a 2-year old male with hypoplastic left heart syndrome who underwent Norwood Stage I and II followed by HF and a 4-year old female with a univentricular heart who developed a severe right ventricular dysfunction 2 years after a cavopulmonary shunt. Mechanical support utilizing ventricular assist devices (VADs) is considered a valid tool to bridge patients with congestive heart failure to either OHT or to recovery. Increasing experience and improved outcomes utilizing this technology in children with biventricular hearts have led to considering employing these devices in failing SV treatment. We present 2 cases of terminally ill children with SV who were assisted with a VAD.

  11. Microstructure of Silicon-alloyed Pyrocarbon for Mechanical Heart Valves%人工心瓣含硅热解炭涂层的微观结构

    Institute of Scientific and Technical Information of China (English)

    张建辉; 孙海博; 王根明; 郭鹏海

    2011-01-01

    为了研究人工心瓣含硅热解炭涂层的微观结构,利用准稳态流化床反应装置制备出了含硅热解炭涂层,利用X射线衍射(XRD)、X射线能谱仪(EDS)、扫描电镜(SEM)、透射电镜(TEM)和偏光显微镜(PLM)对涂层微观结构进行了表征.结果表明,该涂层材料只有乱层结构热解炭和β型碳化硅两种物相,主要由直径为300 nm ~1μm的球形颗粒状碳结构组成,球形颗粒之间由片层状碳结构紧密相连,偶尔会形成闭合孔洞(直径约为0.1 ~1μm).涂层中硅元素宏观均匀分布且含量适中(6.48 wt%),直径约6~8nm的β型碳化硅晶粒无规则取向分布且存在微观尺度的集聚现象.含硅热解炭涂层的这些结构特征决定了其均匀致密、宏观各向同性的特性.%In order to study microstructure of silicon-alloyed pyrocarbon for mechanical heart valves, the silicon-alloyed pyrocarbon coating was prepared by a quasi-steady-state fluidized bed reactor. Microstructure of the coating was investigated by X-ray diffraction ( XRD ) , X-ray energy dispersive spectrometer ( EDS ) , scanning electron microscopy ( SEM ) , transmission electron microscopy ( TEM) and polarized light microscopy ( PLM). The results showed that the coating consisted of two phases, turbostratic pyrocarbon and (3 silicon carbide (β-SiC) , and was mainly composed of spherical particles that were from 300 nm to 1 μm in diameter. These spherical particles, between which there were occasionally pores (about 0. 1 - 1 μm in diameter) , were welded by laminar carbons. The silicon element whose content was moderate (6. 48 wt% ) distributed macro-unifonnly in the coating. The β-SiC grains about 6-8 nm in grain size distributed with random orientation and had some micro-scale agglomeration. These structural features of the silicon-alloyed pyrocarbon coating determined its uniform, dense and macroscopically isotropic properties.

  12. Mechanisms involved in the differential reduction of omega-3 and omega-6 highly unsaturated fatty acids by structural heart disease resulting in "HUFA deficiency".

    Science.gov (United States)

    Rupp, Heinz; Rupp, Thomas P; Alter, Peter; Maisch, Bernhard

    2012-01-01

    The causes of reduced levels of omega-3 and omega-6 highly unsaturated fatty acids ("HUFA deficiency") in heart failure remain unresolved. HUFA profiles were examined in the serum of 331 patients with failing versus nonfailing heart disease. Arachidonic acid was positively correlated (P acid (EPA) (r = 0.40) and docosahexaenoic acid (DHA) (r = 0.53) and negatively with palmitic (r = 0.42), palmitoleic (r = 0.38), and oleic acid (r = 0.48). Delta-5 desaturase activity was reduced (P heart failure patients with low ejection fraction, dilatation, increased wall stress, and reduced heart rate variability (SDNN). In these patients, the reduced (P acid (P = 0.05) arose from separate influences involving reduced cardiac contractility (arachidonic acid and palmitic acid predicted by ejection fraction) and chamber dilatation (DHA and oleic acid predicted by end-diastolic diameter). A low DHA (0.2%-0.9% versus 1.4%-3.1%) was associated (P fatty acid oxidation (CPT-1 inhibition). Based on administration of omega-3 HUFA (OMACOR), dilatation is identified as a target for 1-2 g omega-3 HUFA·day(-1). Interventions for reduced arachidonic acid remain to be explored.

  13. Application of Regent mechanical valve in patients with small aortic annulus: 3-year follow-up

    Directory of Open Access Journals (Sweden)

    Zhao Dong

    2012-09-01

    Full Text Available Abstract Background Aortic valve replacement (AVR with a small aortic annulus is always challenging for the cardiac surgeon. In this study, we sought to evaluate the midterm performance of implantation with a 17-mm or 19-mm St. Jude Medical Regent (SJM Regent mechanical valve in retrospective consecutive cohort of patients with small aortic annulus (diameter ≤ 19 mm. Methods From January 2008 to April 2011, 40 patients (31 female, mean age = 47.2 ± 5.8 years with small aortic annulus (≤19 mm in diameter underwent aortic valve replacement with a 17-mm or 19-mm St. Jude Medical Regent (SJM Regent mechanical valve. Preoperative mean body surface area, New York Heart Association class, and mean aortic annulus were 1.61 ± 0.26 m2, 3.2 ± 0.4, and 18 ± 1.4 mm respectively. Patients were divided into two groups, according to the implantation of 17 mm SJM Regent mechanical valve (group 1, n = 18 or 19 mm SJM Regent valve (group 2, n = 22. All patients underwent echocardiography examination preoperatively and at one year post-operation. Results There were no early deaths in either group. Follow-up time averaged 36 ± 17.6 months. The mean postoperative New York Heart Association class was 1.3 ± 0.6 (p 2/m2 to 69.8 ± 9.3%, 41.4 ± 8.3%, and 0.92 ± 0.10 cm2/m2 respectively (P 2, 46.1 ± 8.5 mmHg to 86.7 ± 18.2 g/m2 , 13.7 ± 5.2 mmHg respectively. In group 2, the LVEF, LVFS and EOAI increased from 45.9% ± 9.7%, 30.7% ± 8.0%, and 0.81 ± 0.09 cm2/m2 to 77.4% ± 9.7%, 44.5% ± 9.6%, and 1.27 ± 0.11 cm2/m2 respectively, while the LVMI, and the aortic transvalvular pressure gradient decreased from 118.3 ± 27.6 g/m2, 44.0 ± 6.7 mmHg to 80.1 ± 19.7 g/m2, 10.8 ± 4.1 mmHg as well. The prevalence of PPM was documented in 2 patients in Group 1. Conclusions Patients with small aortic annulus and body surface

  14. Biological heart valves.

    Science.gov (United States)

    Ciubotaru, Anatol; Cebotari, Serghei; Tudorache, Igor; Beckmann, Erik; Hilfiker, Andres; Haverich, Axel

    2013-10-01

    Cardiac valvular pathologies are often caused by rheumatic fever in young adults, atherosclerosis in elderly patients, or by congenital malformation of the heart in children, in effect affecting almost all population ages. Almost 300,000 heart valve operations are performed worldwide annually. Tissue valve prostheses have certain advantages over mechanical valves such as biocompatibility, more physiological hemodynamics, and no need for life-long systemic anticoagulation. However, the major disadvantage of biological valves is related to their durability. Nevertheless, during the last decade, the number of patients undergoing biological, rather than mechanical, valve replacement has increased from half to more than three-quarters for biological implants. Continuous improvement in valve fabrication includes development of new models and shapes, novel methods of tissue treatment, and preservation and implantation techniques. These efforts are focused not only on the improvement of morbidity and mortality of the patients but also on the improvement of their quality of life. Heart valve tissue engineering aims to provide durable, "autologous" valve prostheses. These valves demonstrate adaptive growth, which may avoid the need of repeated operations in growing patients.

  15. Heart Devices 101: Guide to The Tools That Keep You Ticking

    Science.gov (United States)

    ... heart rhythm when the heart beats too slowly. Implantable cardioverter defibrillators : These deliver a shock to restore ... become blocked again. Ventricular assist devices : These mechanical pumps help weak hearts pump blood effectively. While originally ...

  16. Types of Heart Failure

    Science.gov (United States)

    ... Disease Venous Thromboembolism Aortic Aneurysm More Types of Heart Failure Updated:Feb 9,2017 Left-sided heart failure ... making. This content was last reviewed April 2015. Heart Failure • Home • About Heart Failure Introduction Types of Heart ...

  17. Mechanisms for the adverse effects of late gestational increases in maternal cortisol on the heart revealed by transcriptomic analyses of the fetal septum.

    Science.gov (United States)

    Richards, Elaine M; Wood, Charles E; Rabaglino, Maria Belen; Antolic, Andrew; Keller-Wood, Maureen

    2014-08-01

    We have previously shown in sheep that 10 days of modest chronic increase in maternal cortisol resulting from maternal infusion of cortisol (1 mg/kg/day) caused fetal heart enlargement and Purkinje cell apoptosis. In subsequent studies we extended the cortisol infusion to term, finding a dramatic incidence of stillbirth in the pregnancies with chronically increased cortisol. To investigate effects of maternal cortisol on the heart, we performed transcriptomic analyses on the septa using ovine microarrays and Webgestalt and Cytoscape programs for pathway inference. Analyses of the transcriptomic effects of maternal cortisol infusion for 10 days (130 day cortisol vs 130 day control), or ∼25 days (140 day cortisol vs 140 day control) and of normal maturation (140 day control vs 130 day control) were performed. Gene ontology terms related to immune function and cytokine actions were significantly overrepresented as genes altered by both cortisol and maturation in the septa. After 10 days of cortisol, growth factor and muscle cell apoptosis pathways were significantly overrepresented, consistent with our previous histologic findings. In the term fetuses (∼25 days of cortisol) nutrient pathways were significantly overrepresented, consistent with altered metabolism and reduced mitochondria. Analysis of mitochondrial number by mitochondrial DNA expression confirmed a significant decrease in mitochondria. The metabolic pathways modeled as altered by cortisol treatment to term were different from those modeled during maturation of the heart to term, and thus changes in gene expression in these metabolic pathways may be indicative of the fetal heart pathophysiologies seen in pregnancies complicated by stillbirth, including gestational diabetes, Cushing's disease and chronic stress.

  18. Nerves Regulate Cardiomyocyte Proliferation and Heart Regeneration

    OpenAIRE

    Mahmoud, Ahmed I.; O’Meara, Caitlin C.; Gemberling, Matthew; Zhao, Long; Bryant, Donald M.; Zheng, Ruimao; Gannon, Joseph B.; Cai, Lei; Choi, Wen-Yee; Egnaczyk, Gregory F.; Burns, Caroline E.; Burns, C. Geoffrey; MacRae, Calum A.; Poss, Kenneth D.; Lee, Richard T.

    2015-01-01

    Some organisms, such as adult zebrafish and newborn mice, have the capacity to regenerate heart tissue following injury. Unraveling the mechanisms of heart regeneration is fundamental to understanding why regeneration fails in adult humans. Numerous studies have revealed that nerves are crucial for organ regeneration, thus we aimed to determine whether nerves guide heart regeneration. Here, we show using transgenic zebrafish that inhibition of cardiac innervation leads to reduction of myocyte...

  19. 有创机械通气救治老年急性左心衰临床分析%Clinical study on treatment of senile acute left heart failure by invasive mechanical ventilation

    Institute of Scientific and Technical Information of China (English)

    林长煜

    2014-01-01

    目的:分析有创机械通气救治老年急性左心衰的临床疗效。方法分析我院2011年10月~2013年10月收治的42例老年急性左心衰竭患者,行有创压力支持联合呼气末正压机械通气治疗,比较患者的临床疗效以及治疗前后患者的心率、血压、呼吸频率、血氧饱和度。结果本组42例患者中有效83.3%(35/42)。死亡16.7%(7/42)。死亡原因,1例为室性心动过速,5例心源性休克合并多脏器功能衰竭,1例为顽固性无脉性心衰。治疗后8h、24h比较,与治疗前比较,HR、舒张压、收缩压、R、SpO2水平变化在统计学上有显著意义(P<0.05)。结论有创机械通气治疗急性左心衰竭能够及时有效地缓解急性左心衰所致症状,有效抢救老年急性左心衰竭。%ObjectiveTo analyze the clinical curative effect of senile acute left heart failure by invasive mechanical ventilation.Methods42 cases of acute left heart failure patients in our hospital from 2011 October to 2013 October were analyzed and treated by the method of invasive pressure support combined with mechanical ventilation with positive end expiratory pressure. The clinical efficacy before and after treatment, blood pressure, heart rate, patients with respiratory rate, oxygen saturation of all patients were compared.ResultsThe effective rate and the mortality rate were 83.3% (35/42)and 16.7% (7/42) in all patients. The causes of death were ventricular Beckoning tachycardia(1 cases), cardiogenic shock complicated with multiple organ failure(5 cases) and intractable pulseless heart failure(1 cases). The comparisons of HR, diastolic blood pressure, systolic blood pressure, R and SpO2 levels of 8h and 24h after treatment were statistically significant (P< 0.05).Conclusion Invasive mechanical ventilation in the treatment of acute left heart failure can effectively relieve acute left heart failure symptoms, and can be an effective treatment in elderly acute

  20. Hypertensive heart disease

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/000163.htm Hypertensive heart disease To use the sharing features on this page, please enable JavaScript. Hypertensive heart disease refers to heart problems that occur because of ...

  1. Congenital heart disease

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/001114.htm Congenital heart disease To use the sharing features on this page, please enable JavaScript. Congenital heart disease (CHD) is a problem with the heart's structure ...

  2. Cyanotic heart disease

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/001104.htm Cyanotic heart disease To use the sharing features on this page, please enable JavaScript. Cyanotic heart disease refers to a group of many different heart ...

  3. Who Needs Heart Surgery?

    Science.gov (United States)

    ... this page from the NHLBI on Twitter. Who Needs Heart Surgery? Heart surgery is used to treat ... will work with you to decide whether you need heart surgery. A cardiologist specializes in diagnosing and ...

  4. Heart disease and depression

    Science.gov (United States)

    ... gov/ency/patientinstructions/000790.htm Heart disease and depression To use the sharing features on this page, ... a heart attack or heart surgery Signs of Depression It is pretty common to feel down or ...

  5. Living with Heart Failure

    Science.gov (United States)

    ... page from the NHLBI on Twitter. Living With Heart Failure Currently, heart failure has no cure. You'll ... avoid harmful side effects. Take Steps To Prevent Heart Failure From Getting Worse Certain actions can worsen your ...

  6. Honolulu Heart Program

    Science.gov (United States)

    2016-04-13

    Cardiovascular Diseases; Coronary Disease; Cerebrovascular Accident; Heart Diseases; Heart Failure, Congestive; Myocardial Infarction; Asthma; Emphysema; Lung Diseases, Obstructive; Aortic Aneurysm, Abdominal; Bronchitis; Dementia; Hypertension; Chronic Obstructive Pulmonary Disease; Heart Failure

  7. Left heart catheterization

    Science.gov (United States)

    Catheterization - left heart ... to help guide the catheters up into your heart and arteries. Dye will be injected into your ... in the blood vessels that lead to your heart. The catheter is then moved through the aortic ...

  8. Heart Health Tests

    Science.gov (United States)

    ... is easier to treat. Blood tests and heart health tests can help find heart diseases or identify ... diseases. There are several different types of heart health tests. Your doctor will decide which test or ...

  9. Heart pacemaker - discharge

    Science.gov (United States)

    ... pacemaker can be used for patients with heart failure. It has three leads to help the heart beat in a more coordinated manner. Some pacemakers also can deliver electric shocks to the heart that can stop life-threatening ...

  10. Understanding chronic heart failure

    OpenAIRE

    Fenton, Matthew; Burch, Michael

    2007-01-01

    The key principles of chronic heart failure and the development of clinical management strategies are described. The physiological changes in chronic heart failure and the clinical management of children with heart failure are considered, but the treatment of heart failure related to congenital heart disease or the intensive care management of heart failure are not mentioned as both topics require consideration in their own right. A greater understanding of the maladaptive responses to chroni...

  11. High Altitude and Heart

    Directory of Open Access Journals (Sweden)

    Murat Yalcin

    2011-04-01

    Full Text Available Nowadays, situations associated with high altitude such as mountaineering, aviation increasingly draw the attention of people. Gas pressure decreases and hypoxia is encountered when climbing higher. Physiological and pathological responses of human body to different heights are different. Therefore, physiological and pathological changes that may occur together with height and to know the clinical outcomes of these are important . Acute mountain sickness caused by high altitude and high altitude cerebral edema are preventable diseases with appropriate precautions. Atmospheric oxygen decreasing with height, initiates many adaptive mechanisms. These adaptation mechanisms and acclimatization vary widely among individuals because of reasons such as environmental factors, exercise and cold. High altitude causes different changes in the cardiovascular system with various mechanisms. Although normal individuals easily adapt to these changes, this situation can lead to undesirable results in people with heart disease. For this reason, it should be known the effective evaluation of the people with known heart disease before traveling to high altitude and the complications due to the changes with height and the recommendations can be made to these patients. [TAF Prev Med Bull 2011; 10(2.000: 211-222

  12. Sites and mechanisms responsible for the low rate of free radical production of heart mitochondria in the long-lived pigeon.

    Science.gov (United States)

    Herrero, A; Barja, G

    1997-11-01

    Basal (substrate alone) and maximum rates of H2O2 production, oxygen consumption and free radical leak in the respiratory chain were higher in heart mitochondria of the short-lived rat (4 years) than in the long-lived pigeon (35 years). This suggests that the low free radical production of pigeon heart mitochondria is due in part to both a low electron flow and a low percent leak of electrons out of sequence in the respiratory chain. Thenoyltrifluoroacetone did not increase H2O2 production with succinate either in rats or pigeons. Mitochondrial H2O2 production was higher with pyruvate/malate than with succinate in both animal species. Rotenone and antimycin A increased H2O2 production with pyruvate/malate to the maximum levels observed in each species. Addition of myxothiazol to antimycin A-treated mitochondria supplemented with pyruvate/malate decreased H2O2 production in both species. All the combinations of inhibitors added with pyruvate/malate resulted in higher rates of H2O2 production in rats than in pigeons. When succinate instead of pyruvate/malate was used as substrate, rotenone and thenoyltrifluoroacetone decreased mitochondrial H2O2 production in the rat and did not change it in the pigeon. The results indicate that Complexes I and III are the main H2O2 generators of heart mitochondria in rats and pigeons and that both Complexes are responsible for the low H2O2 production of the bird. p-Chloromercuribenzoate and ethoxyformic anhydride strongly inhibited the H2O2 production induced by rotenone with pyruvate/malate in both species. This suggests that the free radical generator of Complex I is located after the ferricyanide reduction site, between the ethoxyformic and the rotenone-sensitive sites.

  13. Smoking, Stress, and Coronary Heart Disease.

    Science.gov (United States)

    Epstein, Leonard H.; Perkins, Kenneth A.

    1988-01-01

    Focuses on the interrelation between stressors and smoking, and on its potential impact on coronary heart disease risk beyond that due to stressors or to smoking alone. Reviews evidence supporting the stress-smoking interrelationship, its relevance to the risk of heart disease, and mechanisms explaining why smokers smoke more during stress and why…

  14. Do neonatal mouse hearts regenerate following heart apex resection?

    DEFF Research Database (Denmark)

    Andersen, Ditte Caroline; Ganesalingam, Suganya; Jensen, Charlotte Harken;

    2014-01-01

    , the resection border contained a massive fibrotic scar mainly composed of nonmyocytes and collagen disposition. Furthermore, there was a substantial reduction in the number of proliferating cardiomyocytes in AR hearts. Our results thus question the usefulness of the AR model for identifying molecular mechanisms...

  15. Modelling of the concentration--effect relationship of THC on central nervous system parameters and heart rate -- insight into its mechanisms of action and a tool for clinical research and development of cannabinoids.

    Science.gov (United States)

    Strougo, A; Zuurman, L; Roy, C; Pinquier, J L; van Gerven, J M A; Cohen, A F; Schoemaker, R C

    2008-09-01

    Pharmacokinetics after pulmonary administration of delta-9-tetrahydrocannabinol (THC) and its major metabolites 11-OH-THC and 11-nor-9-COOH-THC was quantified. Additionally, the relationship between THC and its effects on heart rate, body sway and several visual analogue scales was investigated using pharmacokinetic-pharmacodynamic (PK-PD) modelling. This provided insights useful for the research and development of novel cannabinoids and the physiology and pharmacology of cannabinoid systems. First, the PK-PD model gave information reflecting various aspects of cannabinoid systems. The delay between THC concentration and effect was quantified in equilibration half-lives of 7.68 min for heart rate and from 39.2 to 84.8 min for the CNS responses. This suggests that the effect of THC on the different responses could be due to different sites of action or different physiological mechanisms. Differences in the shape of the concentration-effect relationship could indicate various underlying mechanisms. Second, the PK-PD model can be used for prediction of THC concentration and effect profiles. It is illustrated how this can be used to optimise studies with entirely different trial designs. Third, many new cannabinoid agonists and antagonists are in development. PK-PD models for THC can be used as a reference for new agonists or as tools to quantitate the pharmacological properties of cannabinoid antagonists.

  16. Curved butterfly bileaflet prosthetic cardiac valve

    Science.gov (United States)

    McQueen, David M.; Peskin, Charles S.

    1991-06-25

    An annular valve body having a central passageway for the flow of blood therethrough with two curved leaflets each of which is pivotally supported on an accentric positioned axis in the central passageway for moving between a closed position and an open position. The leaflets are curved in a plane normal to the eccentric axis and positioned with the convex side of the leaflets facing each other when the leaflets are in the open position. Various parameters such as the curvature of the leaflets, the location of the eccentric axis, and the maximum opening angle of the leaflets are optimized according to the following performance criteria: maximize the minimum peak velocity through the valve, maximize the net stroke volume, and minimize the mean forward pressure difference, thereby reducing thrombosis and improving the hemodynamic performance.

  17. Clinical trial design and rationale of the Multicenter Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy With HeartMate 3 (MOMENTUM 3) investigational device exemption clinical study protocol.

    Science.gov (United States)

    Heatley, Gerald; Sood, Poornima; Goldstein, Daniel; Uriel, Nir; Cleveland, Joseph; Middlebrook, Don; Mehra, Mandeep R

    2016-04-01

    The HeartMate 3 left ventricular assist system (LVAS; St. Jude Medical, Inc., formerly Thoratec Corporation, Pleasanton, CA) was recently introduced into clinical trials for durable circulatory support in patients with medically refractory advanced-stage heart failure. This centrifugal, fully magnetically levitated, continuous-flow pump is engineered with the intent to enhance hemocompatibility and reduce shear stress on blood elements, while also possessing intrinsic pulsatility. Although bridge-to-transplant (BTT) and destination therapy (DT) are established dichotomous indications for durable left ventricular assist device (LVAD) support, clinical practice has challenged the appropriateness of these designations. The introduction of novel LVAD technology allows for the development of clinical trial designs to keep pace with current practices. The prospective, randomized Multicenter Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy With HeartMate 3 (MOMENTUM 3) clinical trial aims to evaluate the safety and effectiveness of the HeartMate 3 LVAS by demonstrating non-inferiority to the HeartMate II LVAS (also St. Jude Medical, Inc.). The innovative trial design includes patients enrolled under a single inclusion and exclusion criteria , regardless of the intended use of the device, with outcomes ascertained in the short term (ST, at 6 months) and long term (LT, at 2 years). This adaptive trial design includes a pre-specified safety phase (n = 30) analysis. The ST cohort includes the first 294 patients and the LT cohort includes the first 366 patients for evaluation of the composite primary end-point of survival to transplant, recovery or LVAD support free of debilitating stroke (modified Rankin score >3), or re-operation to replace the pump. As part of the adaptive design, an analysis by an independent statistician will determine whether sample size adjustment is required at pre-specified times during the study. A further 662

  18. [The role of nitric oxide and superoxide synthesis in protective mechanism of ecdysterone in the heart mitochondria of rats with streptozotocin-induced diabetes].

    Science.gov (United States)

    Korkach, Iu P; Rudyk, O V; Kotsiuruba, A V; Prysiazhna, O D; Sahach, V F

    2007-01-01

    This study evaluated generation of O2*- and NO in heart mitochondria isolated from 9-week old streptozotocin (STZ)-induced diabetic rats and the effect of ecdysterone treatment on these parameters. Mitochondria isolated from 9-week old placebo-treated rats were used as control. Several parameters were evaluated: O2*- production, the levels of stable NO metabolites nitrate, nitrite and total nitrosothiols, the level of bilirubine (as marker of CO generation), inducible (iNOS) and constitutive (nNOS) mtNOS, NADH- dependent nitrate reductase (NR) and inducible arginase II (AII) activity. We observed that diabetes was accompanied by a significant decrease in nNOS activity, nitrite, total nitrosothiols and bilirubine content while iNOS, NR and AII activity, as well as O2*- generation was increased in heart mitochondria. Ecdysterone treatment normalized the levels of stable NO metabolites, ability to generate superoxide, iNOS and nNOS activity, but not bilirubine level, NR and AII activity. These results suggest that ecdysterone treatment attenuates diabetes-induced mitochondrial alterations protecting against oxidative and nitrosative stresses. Thus, ecdysterone therapy, besides its well known importance in the maintenance of glycemic control, may help to protect against mitochondrial dysfunction associated to several age-related disorders.

  19. Take heart!

    CERN Multimedia

    Alizée Dauvergne

    2010-01-01

    Recently, ten new semi-automatic defibrillators were installed at various locations around CERN. This is a preventive measure intended to provide cardiac arrest victims with the best possible response. The first responder could be you!   The Director-General has welcomed the initiative of the Medical Service and Fire Brigade for the installation of ten new semi-automatic defibrillators. You have probably seen them on your way to the restaurant, for example:  brand new semi-automatic defibrillators, ready for an emergency. Housed in a white wall-mounted case, the bright red defibrillators are marked with a white heart symbol crossed by a lightning bolt (see photo). The defibrillator is designed so that anyone can use it. “Anyone can use it, you don’t need to be a health professional,” says Dr Reymond from CERN's Medical Service. Together with the CERN Fire Brigade, he is behind the initiative to have these units put in place. And with good reason, as the unit...

  20. Hypoplastic left heart syndrome (image)

    Science.gov (United States)

    Hypoplastic left heart syndrome is a congenital heart condition that occurs during the development of the heart in the ... womb. During the heart's development, parts of the left side of the heart (mitral valve, left ventricle ...

  1. The contribution of inspiratory muscles function to exercise limitation in heart failure: pathophysiological mechanisms Contribuição da musculatura inspiratória na limitação ao exercício na insuficiência cardíaca: mecanismos fisiopatológicos

    OpenAIRE

    Jorge P. Ribeiro; Chiappa,Gaspar R.; Callegaro,Carine C.

    2012-01-01

    BACKGROUND: Heart failure induces histological, metabolic and functional adaptations in the inspiratory muscles. This inspiratory muscle weakness, which occurs in 30% to 50% of the heart failure patients, is associated with reduction in the functional capacity, reduction in the quality of life and with a poor prognosis in these individuals. OBJECTIVES: The objective of this review was to discuss the pathophysiological mechanisms that may explain the role of the inspiratory muscles in the exer...

  2. What Causes Heart Disease?

    Science.gov (United States)

    ... page from the NHLBI on Twitter. What Causes Heart Disease? Research suggests that coronary heart disease (CHD) begins with damage to the lining and ... causing coronary microvascular disease (MVD). Coronary MVD is heart disease that affects the heart's tiny arteries. The cause ...

  3. Heart Disease in Women

    Science.gov (United States)

    ... United States, 1 in 4 women dies from heart disease. The most common cause of heart disease in both men and women is narrowing or ... It's the major reason people have heart attacks. Heart diseases that affect women more than men include Coronary ...

  4. Mechanisms Involved in the Improvement of Lipotoxicity and Impaired Lipid Metabolism by Dietary α-Linolenic Acid Rich Salvia hispanica L (Salba Seed in the Heart of Dyslipemic Insulin-Resistant Rats

    Directory of Open Access Journals (Sweden)

    Agustina Creus

    2016-01-01

    Full Text Available This study explores the mechanisms underlying the altered lipid metabolism in the heart of dyslipemic insulin-resistant (IR rats fed a sucrose-rich diet (SRD and investigates if chia seeds (rich in α-linolenic acid 18:3, n-3 ALA improve/reverse cardiac lipotoxicity. Wistar rats received an SRD-diet for three months. Half of the animals continued with the SRD up to month 6. The other half was fed an SRD in which the fat source, corn oil (CO, was replaced by chia seeds from month 3 to 6 (SRD+chia. A reference group consumed a control diet (CD all the time. Triglyceride, long-chain acyl CoA (LC ACoA and diacylglycerol (DAG contents, pyruvate dehydrogenase complex (PDHc and muscle-type carnitine palmitoyltransferase 1 (M-CPT1 activities and protein mass levels of M-CPT1, membrane fatty acid transporter (FAT/CD36, peroxisome proliferator activated receptor α (PPARα and uncoupling protein 2 (UCP2 were analyzed. Results show that: (a the hearts of SRD-fed rats display lipotoxicity suggesting impaired myocardial lipid utilization; (b Compared with the SRD group, dietary chia normalizes blood pressure; reverses/improves heart lipotoxicity, glucose oxidation, the increased protein mass level of FAT/CD36, and the impaired insulin stimulated FAT/CD36 translocation to the plasma membrane. The enhanced M-CPT1 activity is markedly reduced without similar changes in protein mass. PPARα slightly decreases, while the UCP2 protein level remains unchanged in all groups. Normalization of dyslipidemia and IR by chia reduces plasma fatty acids (FAs availability, suggesting that a different milieu prevents the robust translocation of FAT/CD36. This could reduce the influx of FAs, decreasing the elevated M-CPT1 activity and lipid storage and improving glucose oxidation in cardiac muscles of SRD-fed rats.

  5. Mechanisms Involved in the Improvement of Lipotoxicity and Impaired Lipid Metabolism by Dietary α-Linolenic Acid Rich Salvia hispanica L (Salba) Seed in the Heart of Dyslipemic Insulin-Resistant Rats.

    Science.gov (United States)

    Creus, Agustina; Ferreira, María R; Oliva, María E; Lombardo, Yolanda B

    2016-01-28

    This study explores the mechanisms underlying the altered lipid metabolism in the heart of dyslipemic insulin-resistant (IR) rats fed a sucrose-rich diet (SRD) and investigates if chia seeds (rich in α-linolenic acid 18:3, n-3 ALA) improve/reverse cardiac lipotoxicity. Wistar rats received an SRD-diet for three months. Half of the animals continued with the SRD up to month 6. The other half was fed an SRD in which the fat source, corn oil (CO), was replaced by chia seeds from month 3 to 6 (SRD+chia). A reference group consumed a control diet (CD) all the time. Triglyceride, long-chain acyl CoA (LC ACoA) and diacylglycerol (DAG) contents, pyruvate dehydrogenase complex (PDHc) and muscle-type carnitine palmitoyltransferase 1 (M-CPT1) activities and protein mass levels of M-CPT1, membrane fatty acid transporter (FAT/CD36), peroxisome proliferator activated receptor α (PPARα) and uncoupling protein 2 (UCP2) were analyzed. Results show that: (a) the hearts of SRD-fed rats display lipotoxicity suggesting impaired myocardial lipid utilization; (b) Compared with the SRD group, dietary chia normalizes blood pressure; reverses/improves heart lipotoxicity, glucose oxidation, the increased protein mass level of FAT/CD36, and the impaired insulin stimulated FAT/CD36 translocation to the plasma membrane. The enhanced M-CPT1 activity is markedly reduced without similar changes in protein mass. PPARα slightly decreases, while the UCP2 protein level remains unchanged in all groups. Normalization of dyslipidemia and IR by chia reduces plasma fatty acids (FAs) availability, suggesting that a different milieu prevents the robust translocation of FAT/CD36. This could reduce the influx of FAs, decreasing the elevated M-CPT1 activity and lipid storage and improving glucose oxidation in cardiac muscles of SRD-fed rats.

  6. 探讨血管内皮损伤致冠心病心绞痛的发生机理%Studying the Mechanism of Damage of Vascular Endotheliocyte Result in Angina Pectoris of Coronary Heart Disease

    Institute of Scientific and Technical Information of China (English)

    韩学杰; 沈绍功

    2001-01-01

    Hyperlipidemia syndrome (Phlegm accumulates with stagnant blood syndrome) is easily to cause disorder or damage of vascular endotheliocyte,which in turn induce angina pectoris of coronary heart disease under stimulation of many kinds of pathogenic factors. According to the theory of Traditional Chinese Medicine,the occurrence of “Xiong Bi” is due to the phlegm and blood stasis which blocks heart meridian. One hypothesis of the mechanisms of phlegm accumulates with stagnant blood are increase of lipoid peroxide,oxygen free radical,attachment of lipoid to vascular endothelia cell,and injury of vascular system. which provides theory basis for study the pathogenesis of angina pectoris of coronary heart disease.%高脂血症(痰瘀互结证)易致血管内皮功能紊乱或损伤,在各种致病因素的刺激下诱发冠心病心绞痛的发作。中医认为“胸痹”的发生是由于“痰瘀互结,阻塞心脉”。痰瘀互结证的物质基础可能是脂质过氧化、氧自由基增多,脂性物质附着在血管内皮上,逐渐损伤血管内皮的病理过程。此假设为研究冠心病心绞痛的发病机制提供理论基础。

  7. Mechanics

    CERN Document Server

    Hartog, J P Den

    1961-01-01

    First published over 40 years ago, this work has achieved the status of a classic among introductory texts on mechanics. Den Hartog is known for his lively, discursive and often witty presentations of all the fundamental material of both statics and dynamics (and considerable more advanced material) in new, original ways that provide students with insights into mechanical relationships that other books do not always succeed in conveying. On the other hand, the work is so replete with engineering applications and actual design problems that it is as valuable as a reference to the practicing e

  8. Heart rate variability in isolated rabbit hearts.

    Science.gov (United States)

    Frey, B; Heger, G; Mayer, C; Kiegler, B; Stöhr, H; Steurer, G

    1996-11-01

    The presence of heart rate variability (HRV) in patients with cardiac denervation after heart transplantation raised our interest in HRV of isolated, denervated hearts. Hearts from seven adult white ELCO rabbits were transferred to a perfusion apparatus. All hearts were perfused in the working mode and in the Langendorff mode for 20 minutes each. HRV was analyzed in the frequency domain. A computer simulated test ECG at a constant rate of 2 Hz was used for error estimation of the system. In the isolated, denervated heart, HRV was of random, broadband fluctuations, different from the well-characterized oscillations at specific frequencies in intact animals. Mean NN was 423 +/- 51 ms in the Langendorff mode, 406 +/- 33 ms in the working heart mode, and 500 ms in the test ECG. Total power was 663 +/- 207 ms2, 817 +/- 318 ms2, and 3.7 ms2, respectively. There was no significant difference in any measure of HRV between Langendorff and working heart modes. The data provide evidence for the presence of HRV in isolated, denervated rabbit hearts. Left atrial and ventricular filling, i.e., the working heart mode, did not alter HRV, indicating that left atrial or ventricular stretch did not influence the sinus nodal discharge rate.

  9. 机械通气治疗113例ICU重症肺心病呼吸衰竭的分析%Analysis of Mechanical Ventilation Therapy of 113 Cases of ICU Severe Pulmonary Heart Disease Patients with Respiratory Failure

    Institute of Scientific and Technical Information of China (English)

    陈光梅

    2016-01-01

    目的:探讨机械通气法治疗重症肺心病呼吸衰竭的临床效果。方法选取收治的113例重症肺心病呼吸衰竭患者使用机械通气法对患者进行治疗,比较患者治疗前后呼吸频率和血气分析指标:动脉血氧分压(PaO2)和动脉血二氧化碳分压(PaCO2)变化。结果患者治疗前后的呼吸频率和PaO2、PaCO2均有明显变化,差异具有统计学意义(P<0.05)。结论使用机械通气法治疗重症肺心病呼吸衰竭可以有效改善患者呼吸衰竭的症状,提高患者的成活率,值得在临床应用中进行推广。%Objective To explore the effect of mechanical ventilation therapy of severe pulmonary heart disease with respiratory failure.Methods 113 cases of severe pulmonary heart disease with respiratory failure were selected retrospectively for the study, who were treated with mechanical ventilation method. Respiratory rate and blood gas analysis indicators including changes of arterial oxygen tension (PaO2) and arterial carbon dioxide tension (PaCO2) of patients before and after treatment were compared.Results The respiratory rate, PaO2, and PaCO2 of patients before and after treatment changed signiifcantly, the differences were statistically signiifcant (P<0.05).Conclusion The use of mechanical ventilation method of severe pulmonary heart disease with respiratory failure can improve respiratory failure symptoms and survival rate of patients, which is worth promoting in clinical applications.

  10. 正压机械通气模式在急性左心衰抢救中的应用分析%Investigate the application of Vary Mechanical ventilation pattern in the saving of acute left heart failure

    Institute of Scientific and Technical Information of China (English)

    陈怡粤; 杨俊芬; 庄义浩

    2009-01-01

    Objective Investigate the clinic curative effect of Vary Mechanical ventilation pattern in the saving of acute left heart failure (ALHF).Methods 87 ALHF patients with conscious disorder were divided into three groups. Control group was treated by conventional therapy. In addition to conventional therapy, treatment group Ⅰ were applied CPAP and treatment group Ⅱ were applied SIMV+PEEP. Evaluating the changes of clinical symptoms, heart rate(HR), blood pressure, pH, PaO2 and PaO2/FiO2 after 2 hours among the groups. Results After 2 hours, the pH, PaO2 and PaO2/FiO2 ratio were significantly increased in the two groups compared with control group (P0.05).治疗组Ⅱ对PaO2/FiO2的改善较治疗组Ⅰ显著(P<0.05),Ⅰ组和Ⅱ组临床表现有效率分别为86.2%和96.5%(P<0.05).结论 根据病情选择合适的正压机械通气方式抢救急性左心衰疗效显著,值得推广.

  11. 国产人工双叶机械瓣置入绵羊肺动脉瓣位的实验研究%Chronic sheep modal for pulmonary valve implantation with domestic bileaflet mechanical prosthesis

    Institute of Scientific and Technical Information of China (English)

    唐跃; 胡盛寿; 孟亮; 仲京; 董以谦; 周燕文; 袁卫民

    2003-01-01

    目的探讨国产人工双叶机械瓣用于绵羊肺动脉瓣位的功能状况及其长期在体内的各项性能. 方法于2001年10 ~11月,在体外循环并行下维持心跳对6只成年绵羊经主肺动脉行肺动脉瓣国产人工双叶机械瓣置换术,长期观察术后绵羊生存时间、机械瓣的功能情况及病理变化. 结果术后6只绵羊全部存活,平均存活(221±208)d,按计划将其中2只绵羊分别于术后41 d和71 d处死,处死前绵羊状况良好,病理检查:机械瓣功能良好,无血栓形成,无瓣周漏,无组织过度生长;1只绵羊于术后158 d 时停用抗凝药物,1周后(165 d)死于白色血栓形成导致的机械瓣功能障碍,病理检查示瓣周缝合缘纤维组织轻度增生;2只绵羊分别于术后196和234 d死于重度贫血,尸检未见其他异常;1只绵羊迄今仍存活(>617 d),并分别于术后438 d和479 d行彩色超声多普勒检查,提示机械瓣在肺动脉瓣位功能正常. 结论在绵羊肺动脉瓣位应用新型国产人造双叶机械瓣,可取得良好的长期效果.

  12. Valvular heart disease in pregnancy.

    Science.gov (United States)

    Windram, Jonathan D; Colman, Jack M; Wald, Rachel M; Udell, Jacob A; Siu, Samuel C; Silversides, Candice K

    2014-05-01

    In women with valvular heart disease, pregnancy-associated cardiovascular changes can contribute to maternal, foetal and neonatal complications. Ideally, a woman with valvular heart disease should receive preconception assessment and counselling from a cardiologist with expertise in pregnancy. For women with moderate- and high-risk valve lesions, appropriate risk stratification and management during pregnancy will optimise outcomes. Pregnancy in women with high-risk lesions, such as severe aortic stenosis, severe mitral stenosis and those with mechanical valves, requires careful planning and coordination of antenatal care by a multidisciplinary team. The purpose of this overview is to describe the expected haemodynamic changes in pregnancy, review pregnancy risks for women with valvular heart disease and discuss strategies for management.

  13. 超声心动图评价心脏机械瓣功能的长期变化趋势%Long term change trend of echocardiographic evaluation of mechanical heart valve function

    Institute of Scientific and Technical Information of China (English)

    陈文斌; 蔡震宇

    2015-01-01

    Objective To explore the long term change trend of echocardiographic evaluation of mechanical heart valve function after mechanical heart valve replacement. Methods 186 patients after mechanical heart valve replacement from June 2012 to June 2014 in our hospital were selected as the research object,the echocardiography data was ana-lyzed,the mechanical valve function of different replacement times,different types in aortic valve replacement and mitral valve replacement patients was compared according to the mechanical valve. Results The Pmax and MGP in the 10-15 years group was higher than that in the 5-10 years group and less than 5 years group,with significant difference (P<0.05). The EOA of each time point of different types of aortic mechanical valve was compared,with statistical differ-ence(P<0.05).The PR,MR,PG,MGP in the 5-10 years group was higher than that in less than 5 years group,with signifi-cant difference (P<0.05).The PR,MR,PG,MGP in the 10-15 years group was higher than that in the 5-10 years group, with significant difference (P<0.05). Conclusion Echocardiographic evaluation can reflect the recessionary situation of mechanical prosthetic valve function,the mechanical valve function in the aortic valve and mitral valve replacement in 5-10 years is gradually declined,so patients should be given regular echocardiographic assessment.%目的:探讨超声心动图评价心脏机械瓣膜置换术后瓣叶功能的长期变化趋势。方法选取2012年6月~2014年6月本院收治的186例心脏机械瓣置换术后患者作为研究对象,分析其超声心动图检查资料,根据置换时间、机械瓣类型等因素比较主动脉瓣置换与二尖瓣置换患者不同置换时间、不同型号的机械瓣功能。结果10~15年组的Pmax、MGP显著高于5~10年组和<5年组,差异有统计学意义(P<0.05)。各时间点不同类型主动脉瓣位机械瓣间EOA比较,差异有统计学意义(P<0.05)。5~10

  14. Mitochondria and the aging heart

    Institute of Scientific and Technical Information of China (English)

    Ketul R Chaudhary; Haitham El-Sikhry; John M Seubert

    2011-01-01

    The average human life span has markedly increased in modern society largely attributed to advances in medical and therapeutic sciences that have successfully reduced important health risks.However,advanced age results in numerous alterations to cellular and subcellular components that can impact the overall health and function of an individual.Not surprisingly,advanced age is a major risk factor for the development of heart disease in which elderly populations observe increased morbidity and mortality.Even healthy individuals that appear to have normal heart fimction under resting conditions,actually have an increased susceptibility and vulnerability to stress.This is confounded by the impact that stress and disease can have over time to both the heart and vessels. Although, there is a rapidly growing body of literature investigating the effects of aging on the heart and how age-related alterations affect cardiac fimction, the biology of aging and underlying mechanisms remain unclear .In this review,we summarize effects of aging on the heart and discuss potential theories of cellular aging with special emphasis on mitochondrial dysfunction.

  15. Exercise Intolerance in Heart Failure

    DEFF Research Database (Denmark)

    Brassard, Patrice; Gustafsson, Finn

    2016-01-01

    Exercise tolerance is affected in patients with heart failure (HF). Although the inability of the heart to pump blood to the working muscle has been the conventional mechanism proposed to explain the lowered capacity of patients with HF to exercise, evidence suggests that the pathophysiological...... mechanisms associated with their exercise intolerance is more complex. Recent findings indicate that lowered cerebral blood flow (CBF) and oxygenation likely represent limiting factors for exercise capacity in patients with HF. After an overview of cardiac and peripheral responses during acute and chronic...... exercise in healthy individuals, we succinctly review cardiac and noncardiac mechanisms by which HF influences exercise tolerance. We then consider how HF, comorbidity, and HF treatment influence CBF and oxygenation at rest and during exercise. Finally, we provide suggestions for further research...

  16. Fusion beat in patients with heart failure treated with left ventricular pacing: may ECG morphology relate to mechanical synchrony? A pilot study

    Directory of Open Access Journals (Sweden)

    Sassone Biagio

    2008-01-01

    Full Text Available Abstract Background Electrical fusion between left ventricular pacing and spontaneous right ventricular activation is considered the key to resynchronisation in sinus rhythm patients treated with single-site left ventricular pacing. Aim Use of QRS morphology to optimize device programming in patients with heart failure (HF, sinus rhythm (SR, left bundle branch block (LBBB, treated with single-site left ventricular pacing. Methods and Results We defined the "fusion band" (FB as the range of AV intervals within which surface ECG showed an intermediate morphology between the native LBBB and the fully paced right bundle branch block patterns. Twenty-four patients were enrolled. Echo-derived parameters were collected in the FB and compared with the basal LBBB condition. Velocity time integral and ejection time did not improve significantly. Diastolic filling time, ejection fraction and myocardial performance index showed a statistically significant improvement in the FB. Interventricular delay and mitral regurgitation progressively and significantly decreased as AV delay shortened in the FB. The tissue Doppler asynchrony index (Ts-SD-12-ejection showed a non significant decreasing trend in the FB. The indications provided by the tested parameters were mostly concordant in that part of the FB corresponding to the shortest AV intervals. Conclusion Using ECG criteria based on the FB may constitute an attractive option for a safe, simple and rapid optimization of resynchronization therapy in patients with HF, SR and LBBB.

  17. P2X4 receptor–eNOS signaling pathway in cardiac myocytes as a novel protective mechanism in heart failure

    Directory of Open Access Journals (Sweden)

    Ronghua Yang

    2015-01-01

    Full Text Available We have demonstrated using immunoprecipitation and immunostaining a novel physical association of the P2X4 receptor (P2X4R, a ligand-gated ion channel, with the cardioprotective, calcium-dependent enzyme endothelial nitric oxide synthase (eNOS. Treatment of murine ventricular myocytes with the P2XR agonist 2-methylthioATP (2-meSATP to induce a current (mainly Na+ increased the formation of nitric oxide (NO, as measured using a fluorescent probe. Possible candidates for downstream effectors mediating eNOS activity include cyclic GMP and PKG or cellular protein nitrosylation. A cardiac-specific P2X4R overexpressing mouse line was protected from heart failure (HF with improved cardiac function and survival in post-infarct, pressure overload, and calsequestrin (CSQ overexpression models of HF. Although the role of the P2X4R in other tissues such as the endothelium and monocytes awaits characterization in tissue-specific KO, cardiac-specific activation of eNOS may be more cardioprotective than an increased activity of global systemic eNOS. The intra-myocyte formation of NO may be more advantageous over NO derived externally from a donor. A small molecule drug stimulating this sarcolemmal pathway or gene therapy-mediated overexpression of the P2X4R in cardiac myocytes may represent a new therapy for both ischemic and pressure overloaded HF.

  18. P2X4 receptor–eNOS signaling pathway in cardiac myocytes as a novel protective mechanism in heart failure

    Science.gov (United States)

    Yang, Ronghua; Beqiri, Dardan; Shen, Jian-Bing; Redden, John M.; Dodge-Kafka, Kimberly; Jacobson, Kenneth A.; Liang, Bruce T.

    2014-01-01

    We have demonstrated using immunoprecipitation and immunostaining a novel physical association of the P2X4 receptor (P2X4R), a ligand-gated ion channel, with the cardioprotective, calcium-dependent enzyme endothelial nitric oxide synthase (eNOS). Treatment of murine ventricular myocytes with the P2XR agonist 2-methylthioATP (2-meSATP) to induce a current (mainly Na+) increased the formation of nitric oxide (NO), as measured using a fluorescent probe. Possible candidates for downstream effectors mediating eNOS activity include cyclic GMP and PKG or cellular protein nitrosylation. A cardiac-specific P2X4R overexpressing mouse line was protected from heart failure (HF) with improved cardiac function and survival in post-infarct, pressure overload, and calsequestrin (CSQ) overexpression models of HF. Although the role of the P2X4R in other tissues such as the endothelium and monocytes awaits characterization in tissue-specific KO, cardiac-specific activation of eNOS may be more cardioprotective than an increased activity of global systemic eNOS. The intra-myocyte formation of NO may be more advantageous over NO derived externally from a donor. A small molecule drug stimulating this sarcolemmal pathway or gene therapy-mediated overexpression of the P2X4R in cardiac myocytes may represent a new therapy for both ischemic and pressure overloaded HF. PMID:25750695

  19. Heart rate variability indices as bio-markers of top-down self-regulatory mechanisms: A meta-analytic review.

    Science.gov (United States)

    Holzman, Jacob B; Bridgett, David J

    2017-03-01

    Theoretical perspectives posit that heart-rate variability (HRV) reflects self-regulatory capacity and therefore can be employed as a bio-marker of top-down self-regulation (the ability to regulate behavioral, cognitive, and emotional processes). However, existing findings of relations between self-regulation and HRV indices are mixed. To clarify the nature of such relations, we conducted a meta-analysis of 123 studies (N=14,347) reporting relations between HRV indices and aspects of top-down self-regulation (e.g., executive functioning, emotion regulation, effortful control). A significant, albeit small, effect was observed (r=0.09) such that greater HRV was related to better top-down self-regulation. Differences in relations were negligible across aspects of self-regulation, self-regulation measurement methods, HRV computational techniques, at-risk compared with healthy samples, and the context of HRV measurement. Stronger relations were observed in older relative to younger samples and in published compared to unpublished studies. These findings generally support the notion that HRV indices can tentatively be employed as bio-markers of top-down self-regulation. Conceptual and theoretical implications, and critical gaps in current knowledge to be addressed by future work, are discussed.

  20. Correctness of multi-detector-row computed tomography for diagnosing mechanical prosthetic heart valve disorders using operative findings as a gold standard

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, I.Chen [Taichung Veterans General Hospital, Department of Radiology, Taichung (China); Institute of Clinical Medicine and Faculty of Medicine, National Yang-Ming University, Taipei (China); Lin, Yung-Kai; Chang, Yen; Wang, Chung-Chi; Hsieh, Shih-Rong; Wei, Hao-Ji; Tsai, Hung-Wen [Taichung Veterans General Hospital, Section of Cardiovascular Surgery, Cardiovascular Center, Taichung (China); Fu, Yun-Ching; Jan, Sheng-Ling [Institute of Clinical Medicine and Faculty of Medicine, National Yang-Ming University, Taipei (China); Taichung Veterans General Hospital, Section of Pediatric Cardiology, Department of Pediatrics, Taichung (China); Wang, Kuo-Yang [Taichung Veterans General Hospital, Section of General Cardiology, Cardiovascular Center, Taichung (China); Chung-Shan Medical University, Department of Medicine, Taichung (China); Chen, Min-Chi; Chen, Clayton Chi-Chang [Taichung Veterans General Hospital, Department of Radiology, Taichung (China); Central Taiwan University of Science and Technology, Department of Radiological Technology, Taichung (China)

    2009-04-15

    The purpose was to compare the findings of multi-detector computed tomography (MDCT) in prosthetic valve disorders using the operative findings as a gold standard. In a 3-year period, we prospectively enrolled 25 patients with 31 prosthetic heart valves. MDCT and transthoracic echocardiography (TTE) were done to evaluate pannus formation, prosthetic valve dysfunction, suture loosening (paravalvular leak) and pseudoaneurysm formation. Patients indicated for surgery received an operation within 1 week. The MDCT findings were compared with the operative findings. One patient with a Bjoerk-Shiley valve could not be evaluated by MDCT due to a severe beam-hardening artifact; thus, the exclusion rate for MDCT was 3.2% (1/31). Prosthetic valve disorders were suspected in 12 patients by either MDCT or TTE. Six patients received an operation that included three redo aortic valve replacements, two redo mitral replacements and one Amplatzer ductal occluder occlusion of a mitral paravalvular leak. The concordance of MDCT for diagnosing and localizing prosthetic valve disorders and the surgical findings was 100%. Except for images impaired by severe beam-hardening artifacts, MDCT provides excellent delineation of prosthetic valve disorders. (orig.)

  1. HEART TRANSPLANTATION IN PATIENTS WITH PREVIOUS OPEN HEART SURGERY

    Directory of Open Access Journals (Sweden)

    R. Sh. Saitgareev

    2016-01-01

    Full Text Available Heart Transplantation (HTx to date remains the most effective and radical method of treatment of patients with end-stage heart failure. The defi cit of donor hearts is forcing to resort increasingly to the use of different longterm mechanical circulatory support systems, including as a «bridge» to the follow-up HTx. According to the ISHLT Registry the number of recipients underwent cardiopulmonary bypass surgery increased from 40% in the period from 2004 to 2008 to 49.6% for the period from 2009 to 2015. HTx performed in repeated patients, on the one hand, involves considerable technical diffi culties and high risks; on the other hand, there is often no alternative medical intervention to HTx, and if not dictated by absolute contradictions the denial of the surgery is equivalent to 100% mortality. This review summarizes the results of a number of published studies aimed at understanding the immediate and late results of HTx in patients, previously underwent open heart surgery. The effect of resternotomy during HTx and that of the specifi c features associated with its implementation in recipients previously operated on open heart, and its effects on the immediate and long-term survival were considered in this review. Results of studies analyzing the risk factors for perioperative complications in repeated recipients were also demonstrated. Separately, HTx risks after implantation of prolonged mechanical circulatory support systems were examined. The literature does not allow to clearly defi ning the impact factor of earlier performed open heart surgery on the course of perioperative period and on the prognosis of survival in recipients who underwent HTx. On the other hand, subject to the regular fl ow of HTx and the perioperative period the risks in this clinical situation are justifi ed as a long-term prognosis of recipients previously conducted open heart surgery and are comparable to those of patients who underwent primary HTx. Studies

  2. Effect of mibefradil on heart rate variability in patients with chronic heart failure

    NARCIS (Netherlands)

    Brouwer, J; de Kam, PJ; Haaksma, J; Crijns, HJGM; van Veldhuisen, DJ

    2000-01-01

    Background: Mibefradil was recently withdrawn from the market because of an unfavorable clinical profile in patients with chronic heart failure. Although drug interactions appear to play a role, other mechanisms such as proarrhythmia and autonomic deterioration could also be relevant. Chronic heart

  3. All about Heart Rate (Pulse)

    Science.gov (United States)

    ... Cholesterol Tools & Resources Congenital Defects Children & Adults About Congenital Heart Defects The Impact of Congenital Heart Defects Understand Your Risk for Congenital Heart Defects Symptoms & ...

  4. Illegal Drugs and Heart Disease

    Science.gov (United States)

    ... Cholesterol Tools & Resources Congenital Defects Children & Adults About Congenital Heart Defects The Impact of Congenital Heart Defects Understand Your Risk for Congenital Heart Defects Symptoms & ...

  5. Comparison between Prothrombin Complex Concentrate (PCC) and Fresh Frozen Plasma (FFP) for the Urgent Reversal of Warfarin in Patients with Mechanical Heart Valves in a Tertiary Care Cardiac Center.

    Science.gov (United States)

    Fariborz Farsad, Bahram; Golpira, Reza; Najafi, Hamideh; Totonchi, Ziae; Salajegheh, Shirin; Bakhshandeh, Hooman; Hashemian, Farshad

    2015-01-01

    Fresh frozen plasma (FFP) and prothrombin complex concentrate (PCC) reverse oral anticoagulants such as Warfarin. We compared the standard dosage of FFP and PCC in terms of efficacy and safety for patients with mechanical heart valves undergoing interventional procedures while receiving Warfarin. Fifty patients were randomized (25 for each group) with mechanical heart valves [international normalized ratio (INR) >2.5]. FFP dosage was administered based on body weight (10-15 mL/Kg), while PCC dosage was administered based on both body weight and target INR. INR measurements were obtained at different time after PCC and FFP infusion. The mean ± SD of INR pre treatment was not significantly different between the PCC and FFP groups. However, over a 48-hour period following the administration of PCC and FFP, 76% of the patients in the PCC group and only 20% of the patients in the FFP group reached the INR target. Five (20%) patients in the PCC group received an additional dose of PCC, whereas 17 (68%) patients in the FFP group received a further dose of FFP (P=0.001). There was no significant difference between the two groups in Hb and Hct before and during a 48-hour period after PCC and FFP infusion. As regards safety monitoring and adverse drug reaction screening in the FFP group, the INR was high (INR > 2.5) in 86% of the patients. There was no report of hemorrhage in both groups. PCC reverses anticoagulation both effectively and safely while having the advantage of obviating the need to extra doses.

  6. Heart Disease Affects Far More Than the Heart

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_163584.html Heart Disease Affects Far More Than the Heart Blocked arteries ... 14, 2017 TUESDAY, Feb. 14, 2017 (HealthDay News) -- Heart disease affects more than just the heart. It also ...

  7. Smoking Thickens Heart Wall, Leading to Heart Failure: Study

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_160932.html Smoking Thickens Heart Wall, Leading to Heart Failure: Study ... 13, 2016 TUESDAY, Sept. 13, 2016 (HealthDay News) -- Smoking leads to heart failure by causing thickened heart ...

  8. Heart transplantation in adult congenital heart disease.

    Science.gov (United States)

    Burchill, Luke J

    2016-12-01

    Heart failure (HF) in adult congenital heart disease (ACHD) is vastly different to that observed in acquired heart disease. Unlike acquired HF in which pharmacological strategies are the cornerstone for protecting and improving ventricular function, ACHD-related HF relies heavily upon structural and other interventions to achieve these aims. patients with ACHD constitute a small percentage of the total adult heart transplant population (∼3%), although the number of ACHD heart transplant recipients is growing rapidly with a 40% increase over the last two decades. The worldwide experience to date has confirmed heart transplantation as an effective life-extending treatment option in carefully selected patients with ACHD with end-stage cardiac disease. Opportunities for improving outcomes in patients with ACHD-related HF include (i) earlier recognition and referral to centres with combined expertise in ACHD and HF, (ii) increased awareness of arrhythmia and sudden cardiac death risk in this population, (iii) greater collaboration between HF and ACHD specialists at the time of heart transplant assessment, (iv) expert surgical planning to reduce ischaemic time and bleeding risk at the time of transplant, (v) tailored immunosuppression in the post-transplant period and (vi) development and validation of ACHD-specific risk scores to predict mortality and guide patient selection. The purpose of this article is to review current approaches to diagnosing and treating advanced HF in patients with ACHD including indications, contraindications and clinical outcomes after heart transplantation.

  9. Effect Evaluation of Dexmedetomidine and Propofol on Heart Operating Patients with Mechanical Ventilation%心脏手术后机械通气患者使用右美托咪啶和丙泊酚效果评价

    Institute of Scientific and Technical Information of China (English)

    王潇毅

    2015-01-01

    Objective To compare sedation effect and difference on intubatton patients after heart operation when using dexmedetomidine and propofol in mechanical ventilation.Methods To collect ICU heart operating patients requiring mechanical ventilation and divide them into two groups. They received intravenously dexmedetomidine or propofol respectively, and keep sedative effect at Ramsay sedation scale 2~4. Compare sedative onset, awake time, duration of ventilator support and blood pressure, heart rate.Results Sedative onset time in Group Dexmedetomidine and Group Propofol were 107.5±16.2s and 120.5±11.3s respectively. There was no significant difference among groups. However awake time in Group Dexmedetomidine(0.55±0.05min) obviously decreased, there was significant difference compared with Group Propofol(14.3±2.0min). Hypotension and intervened bradycardia in Group Dexmedetomidine were no significant increased.Conclusion Dexmedetomidine used in heart operating patients with mechanical ventilation bring about safe and effective sedation.%目的:比较心脏手术后气管插管患者在机械通气镇静时使用右美托咪啶和丙泊酚效果。方法:将42例入住ICU需要机械通气的心脏手术后气管插管患者分成两组,分别应用右美托咪啶镇静和丙泊酚镇静,并维持镇静水平Ramsay2~4级,比较镇静起效时间,唤醒时间,机械通气时间及血压、心率指标。结果:在目标镇静起效时间上两组无显著差异,右美托咪啶组为107.5±16.2秒,丙泊酚组为120.5±11.3秒;停用镇静剂后唤醒时间上右美托咪啶组为0.55±0.05分钟显著优于丙泊酚组14.3±2.0分钟;右美托咪啶组的需要干预的低血压和心动过缓未比丙泊酚组有明显增加。结论:右美托咪啶应用于心脏手术后气管插管机械通气患者镇静效果良好,安全有效。

  10. Inflammation and Heart Disease

    Science.gov (United States)

    ... Disease Venous Thromboembolism Aortic Aneurysm More Inflammation and Heart Disease Updated:Oct 12,2016 Understand the risks of ... inflammation causes cardiovascular disease, inflammation is common for heart disease and stroke patients and is thought to be ...

  11. Aspirin and heart disease

    Science.gov (United States)

    ... medlineplus.gov/ency/patientinstructions/000092.htm Aspirin and heart disease To use the sharing features on this page, ... healthy people who are at low risk for heart disease. You provider will consider your overall medical condition ...

  12. Heart disease and women

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/007188.htm Heart disease and women To use the sharing features on ... please enable JavaScript. People often DO NOT consider heart disease a woman's disease. Yet cardiovascular disease is the ...

  13. Caffeine and Heart Disease

    Science.gov (United States)

    ... Healthy Workplace Food and Beverage Toolkit Caffeine and Heart Disease Updated:Aug 17,2015 Caffeine has many metabolic ... high caffeine intake increases the risk of coronary heart disease is still under study. Many studies have been ...

  14. Know Your Heart's Numbers

    Science.gov (United States)

    ... of body fat based on height and weight), waist circumference, blood sugar and weight. The telephone survey of ... for heart health. Just 36 percent knew that waist circumference is important measure of heart disease risk. The ...

  15. Heart Attack Payment - State

    Data.gov (United States)

    U.S. Department of Health & Human Services — Payment for heart attack patients measure – state data. This data set includes state-level data for payments associated with a 30-day episode of care for heart...

  16. Heart Attack Payment - Hospital

    Data.gov (United States)

    U.S. Department of Health & Human Services — Payment for heart attack patients measure – provider data. This data set includes provider data for payments associated with a 30-day episode of care for heart...

  17. Heart Attack Payment - National

    Data.gov (United States)

    U.S. Department of Health & Human Services — Payment for heart attack patients measure – national data. This data set includes national-level data for payments associated with a 30-day episode of care for heart...

  18. Heart Health for Women

    Science.gov (United States)

    ... it Email Print En Español In Chinese - In Korean - In Vietnamese - In French Creole You may think ... Download and Share: Social Media Toolkit (PDF 481KB) Learn More About Heart Disease: The Heart Truth Campaign ...

  19. Anatomy of the Heart

    Science.gov (United States)

    ... Share this page from the NHLBI on Twitter. Anatomy of the Heart Your heart is located under your ribcage in the center of your chest between your right and left lungs. Its muscular walls beat, or contract, pumping blood ...

  20. Valvular heart disease

    OpenAIRE

    Gelson, E; Gatzoulis, M; Johnson, M.

    2007-01-01

    Valvular disease may be unmasked in pregnancy when physiological changes increase demands on the heart. Women with valvular heart disease require close follow-up during pregnancy, delivery, and postpartum

  1. Heart failure - medicines

    Science.gov (United States)

    ... are working and to measure your potassium levels. Beta Blockers Beta blockers slow your heart rate and decrease the strength ... muscle contracts in the short term. Long term beta blockers help keep your heart failure from becoming worse. ...

  2. Open heart surgery

    Science.gov (United States)

    Heart surgery - open ... lung machine is used in most cases during open heart surgery. While the surgeon works on the ... with these procedures, the surgeon may have to open the chest to do the surgery.

  3. Hypothyroidism and Heart Disease

    Science.gov (United States)

    ... in Balance › Hypothyroidism and Heart Disease Fact Sheet Hypothyroidism and Heart Disease January 2014 Download PDFs English ... nervous system, body temperature, and weight. What is hypothyroidism and what are its symptoms? Hypothyroidism, also called ...

  4. Menopause and Heart Disease

    Science.gov (United States)

    ... Peripheral Artery Disease Venous Thromboembolism Aortic Aneurysm More Menopause and Heart Disease Updated:Aug 30,2016 Heart ... can become more evident after the onset of menopause. Menopause does not cause cardiovascular diseases . However, certain ...

  5. Right heart ventriculography

    Science.gov (United States)

    Angiography - right heart ... The catheter will be moved forward into the right side of the heart. As the catheter is advanced, the doctor can record pressures from the right atrium and right ventricle. Contrast material ("dye") is ...

  6. Heart Diseases--Prevention

    Science.gov (United States)

    ... you have a close family member who had heart disease at an early age. Fortunately, there are many things you can do reduce your chances of getting heart disease. You should Know your blood pressure and keep ...

  7. Stress and Heart Health

    Science.gov (United States)

    ... Recognition & Awards Healthy Workplace Food and Beverage Toolkit Stress and Heart Health Updated:Jun 13,2014 When ... Health and Heart Health Last reviewed 6/2014 Stress Management • Home • How Does Stress Affect You? Introduction ...

  8. Heart failure - home monitoring

    Science.gov (United States)

    ... Mann DL, Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine . 10th ... Mann DL, Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of ...

  9. Heart failure - discharge

    Science.gov (United States)

    ... Mann DL, Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine . 10th ... Mann DL, Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of ...

  10. Heart and Stroke Encyclopedia

    Science.gov (United States)

    ... Venous Thromboembolism Aortic Aneurysm More The Heart and Stroke Encyclopedia Click a letter below to get a ... dozens of cardiovascular terms from our Heart and Stroke Encyclopedia and get links to in-depth information. ...

  11. The mitochondrial uniporter controls fight or flight heart rate increases.

    Science.gov (United States)

    Wu, Yuejin; Rasmussen, Tyler P; Koval, Olha M; Joiner, Mei-Ling A; Hall, Duane D; Chen, Biyi; Luczak, Elizabeth D; Wang, Qiongling; Rokita, Adam G; Wehrens, Xander H T; Song, Long-Sheng; Anderson, Mark E

    2015-01-20

    Heart rate increases are a fundamental adaptation to physiological stress, while inappropriate heart rate increases are resistant to current therapies. However, the metabolic mechanisms driving heart rate acceleration in cardiac pacemaker cells remain incompletely understood. The mitochondrial calcium uniporter (MCU) facilitates calcium entry into the mitochondrial matrix to stimulate metabolism. We developed mice with myocardial MCU inhibition by transgenic expression of a dominant-negative (DN) MCU. Here, we show that DN-MCU mice had normal resting heart rates but were incapable of physiological fight or flight heart rate acceleration. We found that MCU function was essential for rapidly increasing mitochondrial calcium in pacemaker cells and that MCU-enhanced oxidative phoshorylation was required to accelerate reloading of an intracellular calcium compartment before each heartbeat. Our findings show that MCU is necessary for complete physiological heart rate acceleration and suggest that MCU inhibition could reduce inappropriate heart rate increases without affecting resting heart rate.

  12. Mechanics

    CERN Document Server

    Chester, W

    1979-01-01

    When I began to write this book, I originally had in mind the needs of university students in their first year. May aim was to keep the mathematics simple. No advanced techniques are used and there are no complicated applications. The emphasis is on an understanding of the basic ideas and problems which require expertise but do not contribute to this understanding are not discussed. How­ ever, the presentation is more sophisticated than might be considered appropri­ ate for someone with no previous knowledge of the subject so that, although it is developed from the beginning, some previous acquaintance with the elements of the subject would be an advantage. In addition, some familiarity with element­ ary calculus is assumed but not with the elementary theory of differential equations, although knowledge of the latter would again be an advantage. It is my opinion that mechanics is best introduced through the motion of a particle, with rigid body problems left until the subject is more fully developed. Howev...

  13. Congenital Heart Disease in Adults

    Science.gov (United States)

    ... and genetics may play a role. Why congenital heart disease resurfaces in adulthood Some adults may find that ... in following adults with congenital heart disease. Congenital heart disease and pregnancy Women with congenital heart disease who ...

  14. Managing Feelings about Heart Failure

    Science.gov (United States)

    ... About Heart Failure Module 6: Managing Feelings About Heart Failure Download Module Order Hardcopy Heart failure can cause ... professional help for emotional problems. Common Feelings About Heart Failure It is common for people to feel depressed ...

  15. What Are Congenital Heart Defects?

    Science.gov (United States)

    ... page from the NHLBI on Twitter. What Are Congenital Heart Defects? Congenital (kon-JEN-ih-tal) heart defects are problems ... carry blood to the heart or the body Congenital heart defects change the normal flow of blood through the ...

  16. Living with Heart Disease

    Science.gov (United States)

    ... page from the NHLBI on Twitter. Living With Heart Disease If you have coronary heart disease (CHD), you can take steps to control its ... the section of this article titled "How Is Heart Disease Treated?" You also can visit the Health Topics ...

  17. Women and Heart Disease

    Institute of Scientific and Technical Information of China (English)

    邹国如

    2005-01-01

    Heart disease is the leading killer of Americans. But it kills more women than men. The American Heart Association says heart disease and other cardiovascular (心血管的) disorders kill about five hundred thousand women a year. That is more than the next seven causes of death combined.

  18. The Danish Heart Registry

    DEFF Research Database (Denmark)

    Özcan, Cengiz; Juel, Knud; Lassen, Jens Flensted

    2016-01-01

    AIM: The Danish Heart Registry (DHR) seeks to monitor nationwide activity and quality of invasive diagnostic and treatment strategies in patients with ischemic heart disease as well as valvular heart disease and to provide data for research. STUDY POPULATION: All adult (≥15 years) patients...

  19. Heart valve surgery - discharge

    Science.gov (United States)

    ... ACC guideline for the management of patients with valvular heart disease: executive summary: a report of the American College ... Editorial team. Related MedlinePlus Health Topics Heart Surgery Heart Valve Diseases Browse the Encyclopedia A.D.A.M., Inc. ...

  20. Heart Valve Diseases

    Science.gov (United States)

    Your heart has four valves. Normally, these valves open to let blood flow through or out of your heart, and then shut to keep it from flowing ... close tightly. It's one of the most common heart valve conditions. Sometimes it causes regurgitation. Stenosis - when ...

  1. Heart Truth for Latinas

    Science.gov (United States)

    ... That’s a man’s disease.” But here’s The Heart Truth : Heart disease is the #1 killer of Latinas ... TAKING ACTION Now that you know The Heart Truth , what should you do? First, find out your ...

  2. The Heart of Coaching

    Science.gov (United States)

    Docheff, Dennis M.; Gerdes, Dan

    2015-01-01

    This article challenges coaches to address the more personal, human elements of coaching--the HEART of coaching. While there is much research on numerous aspects of coaching, this article provides ideas that make a lasting impact on the hearts of athletes. Using HEART as an acronym, five elements of effective coaching are presented: Humility,…

  3. Heart failure overview

    Science.gov (United States)

    ... symptoms) You feel a severe crushing chest pain Prevention Most cases of heart failure can be prevented by living a healthy lifestyle and taking steps aimed at reducing your risk for heart disease . . Alternative Names CHF; Congestive heart failure; Left-sided ...

  4. Tachycardia | Fast Heart Rate

    Science.gov (United States)

    ... SA) node --- the heart's natural pacemaker - sends out electrical signals faster than usual. The heart rate is fast, but the heart beats properly. Causes of sinus tachycardia A rapid heartbeat may be your body's response to common conditions such as: Fever Anxiety ...

  5. 2015 SCAI/ACC/HFSA/STS Clinical Expert Consensus Statement on the Use of Percutaneous Mechanical Circulatory Support Devices in Cardiovascular Care (Endorsed by the American Heart Association, the Cardiological Society of India, and Sociedad Latino Americana de Cardiologia Intervencion; Affirmation of Value by the Canadian Association of Interventional Cardiology-Association Canadienne de Cardiologie D'intervention).

    Science.gov (United States)

    Rihal, Charanjit S; Naidu, Srihari S; Givertz, Michael M; Szeto, Wilson Y; Burke, James A; Kapur, Navin K; Kern, Morton; Garratt, Kirk N; Goldstein, James A; Dimas, Vivian; Tu, Thomas

    2015-06-01

    Although historically the intra-aortic balloon pump has been the only mechanical circulatory support device available to clinicians, a number of new devices have become commercially available and have entered clinical practice. These include axial flow pumps, such as Impella®; left atrial to femoral artery bypass pumps, specifically the TandemHeart; and new devices for institution of extracorporeal membrane oxygenation. These devices differ significantly in their hemodynamic effects, insertion, monitoring, and clinical applicability. This document reviews the physiologic impact on the circulation of these devices and their use in specific clinical situations. These situations include patients undergoing high-risk percutaneous coronary intervention, those presenting with cardiogenic shock, and acute decompensated heart failure. Specialized uses for right-sided support and in pediatric populations are discussed and the clinical utility of mechanical circulatory support devices is reviewed, as are the American College of Cardiology/American Heart Association clinical practice guidelines.

  6. 2015 SCAI/ACC/HFSA/STS Clinical Expert Consensus Statement on the Use of Percutaneous Mechanical Circulatory Support Devices in Cardiovascular Care (Endorsed by the American Heart Association, the Cardiological Society of India, and Sociedad Latino Americana de Cardiologia Intervencion; Affirmation of Value by the Canadian Association of Interventional Cardiology-Association Canadienne de Cardiologie d'intervention).

    Science.gov (United States)

    Rihal, Charanjit S; Naidu, Srihari S; Givertz, Michael M; Szeto, Wilson Y; Burke, James A; Kapur, Navin K; Kern, Morton; Garratt, Kirk N; Goldstein, James A; Dimas, Vivian; Tu, Thomas

    2015-06-01

    Although historically the intra-aortic balloon pump has been the only mechanical circulatory support device available to clinicians, a number of new devices have become commercially available and have entered clinical practice. These include axial flow pumps, such as Impella(®); left atrial to femoral artery bypass pumps, specifically the TandemHeart; and new devices for institution of extracorporeal membrane oxygenation. These devices differ significantly in their hemodynamic effects, insertion, monitoring, and clinical applicability. This document reviews the physiologic impact on the circulation of these devices and their use in specific clinical situations. These situations include patients undergoing high-risk percutaneous coronary intervention, those presenting with cardiogenic shock, and acute decompensated heart failure. Specialized uses for right-sided support and in pediatric populations are discussed and the clinical utility of mechanical circulatory support devices is reviewed, as are the American College of Cardiology/American Heart Association clinical practice guidelines.

  7. 2015 SCAI/ACC/HFSA/STS Clinical Expert Consensus Statement on the Use of Percutaneous Mechanical Circulatory Support Devices in Cardiovascular Care: Endorsed by the American Heart Assocation, the Cardiological Society of India, and Sociedad Latino Americana de Cardiologia Intervencion; Affirmation of Value by the Canadian Association of Interventional Cardiology-Association Canadienne de Cardiologie d'intervention.

    Science.gov (United States)

    Rihal, Charanjit S; Naidu, Srihari S; Givertz, Michael M; Szeto, Wilson Y; Burke, James A; Kapur, Navin K; Kern, Morton; Garratt, Kirk N; Goldstein, James A; Dimas, Vivian; Tu, Thomas

    2015-05-19

    Although historically the intra-aortic balloon pump has been the only mechanical circulatory support device available to clinicians, a number of new devices have become commercially available and have entered clinical practice. These include axial flow pumps, such as Impella(®); left atrial to femoral artery bypass pumps, specifically the TandemHeart; and new devices for institution of extracorporeal membrane oxygenation. These devices differ significantly in their hemodynamic effects, insertion, monitoring, and clinical applicability. This document reviews the physiologic impact on the circulation of these devices and their use in specific clinical situations. These situations include patients undergoing high-risk percutaneous coronary intervention, those presenting with cardiogenic shock, and acute decompensated heart failure. Specialized uses for right-sided support and in pediatric populations are discussed and the clinical utility of mechanical circulatory support devices is reviewed, as are the American College of Cardiology/American Heart Association clinical practice guidelines.

  8. Elevated heart rate and nondipping heart rate as potential targets for melatonin: a review.

    Science.gov (United States)

    Simko, Fedor; Baka, Tomas; Paulis, Ludovit; Reiter, Russel J

    2016-09-01

    Elevated heart rate is a risk factor for cardiovascular and all-cause mortalities in the general population and various cardiovascular pathologies. Insufficient heart rate decline during the night, that is, nondipping heart rate, also increases cardiovascular risk. Abnormal heart rate reflects an autonomic nervous system imbalance in terms of relative dominance of sympathetic tone. There are only a few prospective studies concerning the effect of heart rate reduction in coronary heart disease and heart failure. In hypertensive patients, retrospective analyses show no additional benefit of slowing down the heart rate by beta-blockade to blood pressure reduction. Melatonin, a secretory product of the pineal gland, has several attributes, which predict melatonin to be a promising candidate in the struggle against elevated heart rate and its consequences in the hypertensive population. First, melatonin production depends on the sympathetic stimulation of the pineal gland. On the other hand, melatonin inhibits the sympathetic system in several ways representing potentially the counter-regulatory mechanism to normalize excessive sympathetic drive. Second, administration of melatonin reduces heart rate in animals and humans. Third, the chronobiological action of melatonin may normalize the insufficient nocturnal decline of heart rate. Moreover, melatonin reduces the development of endothelial dysfunction and atherosclerosis, which are considered a crucial pathophysiological disorder of increased heart rate and pulsatile blood flow. The antihypertensive and antiremodeling action of melatonin along with its beneficial effects on lipid profile and insulin resistance may be of additional benefit. A clinical trial investigating melatonin actions in hypertensive patients with increased heart rate is warranted.

  9. Focus on renal congestion in heart failure.

    Science.gov (United States)

    Afsar, Baris; Ortiz, Alberto; Covic, Adrian; Solak, Yalcin; Goldsmith, David; Kanbay, Mehmet

    2016-02-01

    Hospitalizations due to heart failure are increasing steadily despite advances in medicine. Patients hospitalized for worsening heart failure have high mortality in hospital and within the months following discharge. Kidney dysfunction is associated with adverse outcomes in heart failure patients. Recent evidence suggests that both deterioration in kidney function and renal congestion are important prognostic factors in heart failure. Kidney congestion in heart failure results from low cardiac output (forward failure), tubuloglomerular feedback, increased intra-abdominal pressure or increased venous pressure. Regardless of the cause, renal congestion is associated with increased morbidity and mortality in heart failure. The impact on outcomes of renal decongestion strategies that do not compromise renal function should be explored in heart failure. These studies require novel diagnostic markers that identify early renal damage and renal congestion and allow monitoring of treatment responses in order to avoid severe worsening of renal function. In addition, there is an unmet need regarding evidence-based therapeutic management of renal congestion and worsening renal function. In the present review, we summarize the mechanisms, diagnosis, outcomes, prognostic markers and treatment options of renal congestion in heart failure.

  10. The Danish Heart Registry

    DEFF Research Database (Denmark)

    Özcan, Cengiz; Juel, Knud; Flensted Lassen, Jens;

    2016-01-01

    AIM: The Danish Heart Registry (DHR) seeks to monitor nationwide activity and quality of invasive diagnostic and treatment strategies in patients with ischemic heart disease as well as valvular heart disease and to provide data for research. STUDY POPULATION: All adult (≥15 years) patients...... undergoing coronary angiography (CAG), percutaneous coronary intervention (PCI), coronary artery bypass grafting, and heart valve surgery performed across all Danish hospitals were included. MAIN VARIABLES: The DHR contains a subset of the data stored in the Eastern and Western Denmark Heart Registries (EDHR...

  11. Heart Age PSA (:60)

    Centers for Disease Control (CDC) Podcasts

    2015-09-01

    This 60 second public service announcement is based on the September 2015 CDC Vital Signs report. Your heart age is the age of your heart and blood vessels as a result of your risk factors for heart attack and stroke. If you smoke or have high blood pressure, your heart age will be much higher than your actual age. Learn what you can do to lower your heart age and keep it low.  Created: 9/1/2015 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 9/1/2015.

  12. Multiplexin promotes heart but not aorta morphogenesis by polarized enhancement of slit/robo activity at the heart lumen.

    Science.gov (United States)

    Harpaz, Nofar; Ordan, Elly; Ocorr, Karen; Bodmer, Rolf; Volk, Talila

    2013-06-01

    The Drosophila heart tube represents a structure that similarly to vertebrates' primary heart tube exhibits a large lumen; the mechanisms promoting heart tube morphology in both Drosophila and vertebrates are poorly understood. We identified Multiplexin (Mp), the Drosophila orthologue of mammalian Collagen-XV/XVIII, and the only structural heart-specific protein described so far in Drosophila, as necessary and sufficient for shaping the heart tube lumen, but not that of the aorta. Mp is expressed specifically at the stage of heart tube closure, in a polarized fashion, uniquely along the cardioblasts luminal membrane, and its absence results in an extremely small heart tube lumen. Importantly, Mp forms a protein complex with Slit, and interacts genetically with both slit and robo in the formation of the heart tube. Overexpression of Mp in cardioblasts promotes a large heart lumen in a Slit-dependent manner. Moreover, Mp alters Slit distribution, and promotes the formation of multiple Slit endocytic vesicles, similarly to the effect of overexpression of Robo in these cells. Our data are consistent with Mp-dependent enhancement of Slit/Robo activity and signaling, presumably by affecting Slit protein stabilization, specifically at the lumen side of the heart tube. This activity results with a Slit-dependent, local reduction of F-actin levels at the heart luminal membrane, necessary for forming the large heart tube lumen. Consequently, lack of Mp results in decreased diastolic capacity, leading to reduced heart contractility, as measured in live fly hearts. In summary, these findings show that the polarized localization of Mp controls the direction, timing, and presumably the extent of Slit/Robo activity and signaling at the luminal membrane of the heart cardioblasts. This regulation is essential for the morphogenetic changes that sculpt the heart tube in Drosophila, and possibly in forming the vertebrates primary heart tube.

  13. 机械心脏瓣膜术后患者自我管理行为的研究%Research for self- management action of patient suffered from mechanical heart valve post-operation

    Institute of Scientific and Technical Information of China (English)

    李飞霞; 袁述兰; 梁克

    2011-01-01

    目的 探讨机械心脏瓣膜术后患者行为的自我管理.方法 将168例机械心脏瓣膜术后患者随机分为干预组86例和对照组82例.干预组患者在常规药物治疗的同时给予有针对性的自我管理教育,而对照组患者在常规药物治疗的同时则行常规健康教育,分别于治疗护理1年后采用"自我管理行为量表"对两组患者进行测定,评估两组患者的自我管理行为,并应用中文版SF-36量表对两组患者进行评价,比较两组患者的生活质量(QOL).结果 治疗护理1年后,干预组患者的自我管理行为量表及SF-36量表的各项评分均明显高于对照组,两组比较差异均有统计学意义(P<0.01).结论 自我管理教育可帮助患者建立良好的健康行为模式,能提高患者自我管理疾病的能力,减少并发症的发生,从而促进康复,达到提高机械心脏瓣膜术后患者生活质量的目的.%Objective To explore the self-management action of patient suffered from mechanical heart valve post-operation. Methods 168cases of the patients suffered from the mechanical heart valve post-operation were separately divided into 86 cases as the interference group and 82 cases as control group at random. The interference group was given for the normal medical treatment and also objective self-management education but the control group used normal medical treatment and also health education. Two groups of the patients were tested by "Self-Management Action Measurement Form" separately to asseSS the self-management action and also were assessed by Chinese version of SF-36 Measurement Form for the assessment of two groups of the patients for the comparison of the patients of two groups in living quality(QOL) one year after treatment and nursing. Results The various items of assessments of interference group were higher than the comparison group in self-management action measurement form SF-36 Measurement Form with the difference of statistics meaning

  14. Effects of Different Types of Mechanical Valves on Hemodynamics in Patients Undergoing Mitral Valve Replacement%不同类型机械瓣对二尖瓣置换术患者术后血流动力学的影响

    Institute of Scientific and Technical Information of China (English)

    蒙俊

    2016-01-01

    (Department of Cardiovascular Surgery,The First Affiliated Hospital of Kunming Medical University,Kunming 650032,Yunnan,China) Objective To investigate the hemodynamics influence of different types of mechanical valve in patients with mitral valve replacement. Methods 52 patients who underwent mitral valve replacement in our hospital were selected as research object,according to the different type of mechanical valves were divided into bileaflet valve group and tilting disc valve group,26 cases in each group.After one years of follow-up,observed the hemodynamic parameters of cases in two groups.Results The difference of left atrial diameter (LA)and E wave peak velocity between bileaflet group and tilting disc valve group was statistically significant ( 0.05).Conclusion Bileaflet valve has better hemodynamic influence than tilting disk valve in patients with mitral valve replacement.%目的探讨不同类型机械瓣对二尖瓣置换术患者术后血流动力学的影响.方法选择我院收治的52例行二尖瓣置换术患者作为研究对象,根据术中使用机械瓣类型的不同将患者分为双叶瓣组和倾斜碟瓣两组,每组26例,术后对患者进行1年的随访,观察两组患者手术后的血流动力学超声参数.结果双叶瓣组和倾斜碟瓣组患者术后左房内径(LA)及E波峰值速度之间的差异有统计学意义(<0.05).两组患者的左室内径(LV)/右室内径(RV)/平均跨瓣压差(MPG)以及肺动脉收缩压(PASP)组间差异未见统计学意义(>0.05).结论在二尖瓣置换手术中使用双叶瓣对患者血流动力学的影响优于倾斜碟瓣.

  15. Mechanisms, diagnoses and therapies of heart failure with preserved ejection fraction%慢性射血分数保留心力衰竭的发病机制与诊治

    Institute of Scientific and Technical Information of China (English)

    赵鹏; 李玉明

    2015-01-01

    Heart failure with left ventricular ejection fraction is not common, which is named HF with preserved EF (HF-pEF), is increasingly predominant form of HF in the real world. Its morbidity and mortality are equal with HF with reduced EF (HF-rEF) and it remains the most challenging of clinical syndromes for the practicing clinician, with a multitude of proposed mechanisms involving the heart and other organs and complex interplay with common comorbidities. As the list of failed treatments continues to grow, HF-pEF clearly represents a major unmet medical need. In this article, we provide an overview of HF-pEF for both the clinical and basic research, which includes a brief examination of its evolving epidemiology, a summary of proposed mechanisms, the diagnostic criteria, a review of our valiant but unsuccessful prior efforts to develop an effective therapy and a discussion of newer potential approaches.%左心室射血分数保留的心力衰竭(HF-pEF)在临床中较常见,处理此类心力衰竭对临床医生是一个挑战。HF-pEF的发病率和死亡率与左心室射血分数降低的心力衰竭(HF-rEF)相同,且发病机制更加复杂,既有心脏本身也有其他脏器的异常,同时还存在多种并发症间的相互作用影响。现有治疗心力衰竭的多数药物对于HFpEF无效,因此这类患者应该受到更多的关注。本文基于临床实践和基础研究,总结了HFpEF的流行病学特点、发病机制、诊断标准、医学上曾经尝试过的治疗方法,并对未来治疗本病的新手段进行讨论。

  16. Optical coherence tomography provides an ability to assess mechanical property of cardiac wall of developing outflow tract in embryonic heart in vivo

    Science.gov (United States)

    Li, Peng; Wang, Ruikang K.

    2012-12-01

    Knowledge of the biomechanical/elastic property of the cardiac wall is of fundamental importance in improving our understanding of cardiac development, particularly the interaction between the wall dynamics and hemodynamics in the developing outflow tract (OFT). We describe a method that employs optical coherence tomography (OCT) as a means to noninvasively measure the local elastic property of the cardiac wall in vivo. The method uses a time-lapse sequence of OCT images that represent the dynamic behavior of the OFT longitudinal section to calculate the regional wall pulse wave velocity (PWV), upon which the Young's modulus of the cardiac wall is deduced by the use of the Moens-Korteweg equation. The experimental results show that the foot-to-foot PWV ranges from 3.2 to 6.6 mm/s with a mean of 4.7 mm/s, and the averaged Young's modulus is 0.36 Pa, both of which are comparable to the documented values of stage HH17 atrioventricular canal tissue. The proposed method that provides the quantitative mechanical assessment may play a significant role in the understanding of the cardiac development.

  17. Ischemic heart disease in women

    Directory of Open Access Journals (Sweden)

    Stella Iraklianou

    2009-10-01

    Full Text Available Coronary heart disease has long been recognized as the leading cause of death among middle-aged men and an equally important cause of death and disability among older women. Women with acute ischemic syndromes tend to be older than men with such syndromes. This is considered to be attributed to the protective effects of female ovarian sex hormones. Estrogen express an antiatherogenic profile via mechanisms that cause favorable modifications of lipoprotein levels, coagulation and fibrolytic system and alterations in the wall of vessels that cause vasodilation. Women are susceptible to coronary heart disease because of differences in the anatomy and physiology of their vessels. Women's coronary arteries are smaller and have more diffuse disease than men's. Ischemia can be induced in women without flow limiting stenosis because of endothelial dysfunction or coronary spasm. Usually, the way of manifestation of the disease and ECG abnormalities are not typical in women. Female patients usually delay to seek treatment for their symptoms .The way of evaluation and treatment is usually conservative in women than male counterparts. The diagnosis of the disease is overestimated in men and the treatment is more often invasive, even in the category of low risk. Reversely, women of high risk are less likely to undergo a full assessment and invasive diagnostic and therapeutic interventions are seldom. Recommendations of the American Heart Association for ischemic heart disease in women are in accordance to alterations in the way of life interventions in major risk factors such as arterial hypertension, dyslipidemia and diabetes mellitus, preventive use of medications and drugs that are not recommended. In this category of medications belong hormone replacement therapy (HRT.The last is not recommended for primary and secondary prevention of coronary heart disease in women.

  18. Patterns of Heart Attacks

    Science.gov (United States)

    2010-06-01

    Hypertension (high blood pressure), smoking, family history of heart disease, and diabetes mellitus (both types 1 and 2) are also factors that increase the risk...breath 16% 19% Hyperlipidemia 2% Asthma 23% Coronary Artery Disease 15% Chest Pain 4% Pneumonia 24% 38% Diabetes 7% Congestive Heart Failure 9% 6...Pain Diabetes Congestive Heart Failure Hypertension Asthma Table 5.7: Diagnoses that distinguish cluster 8 from the cost bucket 2 population average. The

  19. Pediatric cardiology. Clinical and practical experiences with heart diseases of children, juveniles and young adults; Kinderkardiologie. Klinik und Praxis der Herzerkrankungen bei Kindern, Jugendlichen und jungen Erwachsenen

    Energy Technology Data Exchange (ETDEWEB)

    Haas, Nikolaus A. [Herz- und Diabeteszentrum NRW, Bad Oeynhausen (Germany). Klinik fuer angeborene Herzfehler; Kleideiter, Ulrich [Klinik fuer Kinder- und Jugendmedizin, Coesfeld (Germany)

    2011-07-01

    The book on pediatric cardiology covers the following chapters: (I) Fundamentals and diagnostics: pediatric cardiologic anamnesis, electrocardiograms, thorax X-radiography, MRT and CT of the heart, nuclear medical diagnostics, exercise tests, heart catheter examination, electrophysiological tests. (II) Leading symptoms: Cyanosis, cardiac murmur, thorax pain, palpitation, syncopes. (III) Disease pictures: congenital heart defects, acquired heart defects, cardiomyopathies, heart rhythm disturbances, heart insufficiency, arterial hypertension, pulmonary hypertension, other heart involving syndromes. (IV) Therapy: Catheter interventional therapy, post-surgical pediatric cardiac therapy, surgery involving the life-support machine, mechanical cardiovascular support systems, initial treatment of newborns with critical heart defects, heart transplantation, vaccination of children with heart diseases, medicinal therapy.

  20. Genetics of Congenital Heart Disease: Past and Present.

    Science.gov (United States)

    Muntean, Iolanda; Togănel, Rodica; Benedek, Theodora

    2016-11-02

    Congenital heart disease is the most common congenital anomaly, representing an important cause of infant morbidity and mortality. Congenital heart disease represents a group of heart anomalies that include septal defects, valve defects, and outflow tract anomalies. The exact genetic, epigenetic, or environmental basis of congenital heart disease remains poorly understood, although the exact mechanism is likely multifactorial. However, the development of new technologies including copy number variants, single-nucleotide polymorphism, next-generation sequencing are accelerating the detection of genetic causes of heart anomalies. Recent studies suggest a role of small non-coding RNAs, micro RNA, in congenital heart disease. The recently described epigenetic factors have also been found to contribute to cardiac morphogenesis. In this review, we present past and recent genetic discoveries in congenital heart disease.

  1. Connection forms for beating the heart

    DEFF Research Database (Denmark)

    Mensch, Arthur; Piuze, Emmanuel; Lehnert, Lucas

    2014-01-01

    We combine recent work on modeling cardiac mechanics using a finite volume method with the insight that heart wall myofiber orientations exhibit a particular volumetric geometry. In our finite vol- ume mechanical simulation we use Maurer-Cartan one-forms to add a geometrical consistency term...... to control the rate at which myofiber ori- entation changes in the direction perpendicular to the heart wall. This allows us to estimate material properties related to both the passive and active parameters in our model. We have obtained preliminary results on the 4 canine datasets of the 2014 mechanics...... challenge using the FEBio software suite. In ongoing work we are validating and improving the model using rat heart (ex-vivo DTI and in-vivo tagging) MRI datasets, from which we have estimated strain tensors....

  2. The Analysis of Early-Term Surgical Complications Following Mechanical Heart Valve Replacement%人工机械瓣膜替换术后早期并发症分析

    Institute of Scientific and Technical Information of China (English)

    杜心灵; 孙宗全; 张宏超; 苏伟; 蓝鸿均

    2001-01-01

    1987年1月至2000年4月,共施行人工机械瓣膜替换手术700例,其中二尖瓣替换术398例,主动脉瓣替换术81例,二尖瓣和主动脉瓣替换术213例,三尖瓣替换术8例.158例患者术中和术后早期发生并发症,发生率为22.6%,死亡44例,死亡率6.3%.死亡原因主要为低心排出量综合征、严重感染和心律失常等.%From Jan. 1987 to Apr. 2000, 700 patients received mechanical heart valve insertion in our hospital. Among them 398 underwent mitral valve replacement, 81 aortic valve replacement, 213 mitral and aortic valve replacement, and 8 tricuspid valve replacement. Surgical complications occurred in 158 cases (22.6 %) during or after operation. Forty-four patients died with a mortality rate of 6.3 %. Low cardiac output syndrome, serious infection and arrhythmia were the main causes of death.

  3. Therapeutic options in chronic heart failure. Findings on chest X-ray; Nicht medikamentoese Therapieoptionen der chronischen Herzinsuffizienz. Befunde in der Projektionsradiografie des Thorax

    Energy Technology Data Exchange (ETDEWEB)

    Granitz, M.R.; Meissnitzer, T.; Meissnitzer, M.W.; Hergan, K.; Altenberger, J.; Granitz, C. [Uniklinikum Salzburg - Landeskrankenhaus (Austria)

    2016-05-15

    The contribution covers drugless therapeutic options for chronic heart failure: the implantable cardioverter/defibrillator (ICD), the cardiac resynchronization therapy (CRT), the interventional catheter treatment of functional mitral insufficiency, and mechanical heart supporting systems and heart transplantation.

  4. 无创通气改善心脏术后呼吸功能不全患者心功能的效果%Effect of noninvasive mechanical ventilation on cardiac function after the heart surgery

    Institute of Scientific and Technical Information of China (English)

    章淬; 穆心苇; 王翔; 施乾坤; 李静; 程子昊

    2011-01-01

    目的 观察无创通气对心脏术后患者血流动力学的影响.方法 对心脏术后在气管插管拔除后出现呼吸功能不全的患者48例实施无创通气治疗.记录无创通气前(T0)、无创通气30 min(T1)、1 h(T2)、2 h(T3)、4 h(T4)的脉搏氧饱和度(SpO2)、氧合指数(OI)、平均动脉压(MAP)、心率(HR)、中心静脉压(CVP)、心指数(CI)、右心射血分数(RVEF)、右室舒张末容积(RVEDV)、平均肺动脉压(MPAP)、肺血管阻力指数(PVRI).结果 与T0比较,HR、MAP、CVP、RVEDV在T1、T2、T3、T4时均无明显变化(P>0.05) ;MPAP在T4时明显降低(P<0.05);PVRI在T3、T4时明显降低(P<0.05);CI、RVEF在T3、T4时明显升高(P<0.05);SpO2和OI在T2、T3、T4时明显上升(P<0.05).结论 心脏术后出现呼吸功能不全时进行无创通气治疗可明显改善心功能.%Objective To investigate the effects of nomnvasive mechanical ventilation on hemodynamics after heart surgery. Methods Noninvasive mechanical ventilation was performed in 48 patients underwent cardiosurgery with respiratory insufficiency after extubation. The pulsed oxygen saturation(SpO2),oxygenation index(OI), mean arterial pressure(MAP), heart rate(HR), central venous pressure(CVP), cardiac index( CI), right ventricular ejection fraction(RVEF), right ventricular end-diastolic volume ( RVEDV), mean pulmonary artery pressure (MPAP) and pulmonary vascular resistance index(PVRI) were recorded after extubation (TO), at 30 min(Tl), 60 min(T2), 120 min (T3) and 240 min(T4) during noninvasive mechanical ventilatioa Results Compared with T0,there were no remarkable changes of HR,MAP,CVP and RVEDV at T1,T2,T3 and T4(P>0. 05),but CI and RVEF were highly increased at T3 and T4(P<0. 05),MPAP was decreased at T4(P<0. 05), PVRI was decreased at T3 and T4(P<0. 05),and SpO2. And OI were highly increased at T2,T3 and T4(P<0. 05). Conclusion The noninvasive mechanical ventilation can effectively improve cardiac function in the

  5. [Atrial fibrillation concomitant with valvular heart disease].

    Science.gov (United States)

    Ishii, Yosuke

    2013-01-01

    Patients with valvular heart disease frequently have atrial fibrillation(AF) due to elevated pressure and dilatation of the left and right atria and pulmonary veins. Guidelines for valvular heart disease and AF recommend that surgical treatment for the valvular heart disease should be performed concomitantly with AF surgery. The Full-Maze procedure has evolved into the gold standard of treatment for medically refractory AF. In addition to the pulmonary vein isolation, the right and left atrial incisions of the Full-Maze procedure are designed to block potential macroreentrant pathways. According to the mechanisms of AF with valvular heart disease, the Full-Maze procedure is more effective for the patients than the pulmonary vein isolation alone.

  6. Medicinal Chemistry Approaches to Heart Regeneration.

    Science.gov (United States)

    Schade, Dennis; Plowright, Alleyn T

    2015-12-24

    Because of the minimal and clearly insufficient ability of the adult heart to regenerate after ischemic injury, there is a great opportunity to identify biological mechanisms, substances, and factors that enhance this process. Hence, innovative therapeutic management of heart failure following infarction requires a paradigm shift in pharmacotherapy. Spurred by tremendous progress in the field of stem cell and cardiac biology, several attractive approaches for regeneration of lost cardiomyocytes and supporting vasculature have emerged. Research in this area focuses on restoring the hearts' original function via proliferation and differentiation of cardiac progenitor cells, proliferation of pre-existing cardiomyocytes, and reprogramming of cardiac fibroblasts. In this review, we outline these principal strategies, putative biological targets or signaling pathways and chemical agents, with a focus on small molecules, to achieve therapeutic heart regeneration. We also point out the many remaining questions and challenges, particularly for translating in vitro discoveries to in vivo application.

  7. Women and Heart Disease: Sharing Advice from the Heart

    Science.gov (United States)

    ... page please turn JavaScript on. Feature: Women and Heart Disease Sharing Advice From The Heart Past Issues / Spring ... gowns in an effort to raise awareness that heart disease is the leading cause of death among women. ...

  8. Women's Heart Disease: Join the Heart Truth Community

    Science.gov (United States)

    ... this page please turn JavaScript on. Feature: Women's Heart Disease Join The Heart Truth Community Past Issues / Winter ... introduced as the national symbol for women and heart disease awareness in 2002 by the NHLBI. The Red ...

  9. Dimensional analysis of heart rate variability in heart transplant recipients

    Energy Technology Data Exchange (ETDEWEB)

    Zbilut, J.P.; Mayer-Kress, G.; Geist, K.

    1987-01-01

    We discuss periodicities in the heart rate in normal and transplanted hearts. We then consider the possibility of dimensional analysis of these periodicities in transplanted hearts and problems associated with the record.

  10. Congestive Heart Failure and Central Sleep Apnea.

    Science.gov (United States)

    Sands, Scott A; Owens, Robert L

    2016-03-01

    Congestive heart failure (CHF) is among the most common causes of admission to hospitals in the United States, especially in those over age 65. Few data exist regarding the prevalence CHF of Cheyne-Stokes respiration (CSR) owing to congestive heart failure in the intensive care unit (ICU). Nevertheless, CSR is expected to be highly prevalent among those with CHF. Treatment should focus on the underlying mechanisms by which CHF increases loop gain and promotes unstable breathing. Few data are available to determine prevalence of CSR in the ICU, or how CSR might affect clinical management and weaning from mechanical ventilation.

  11. Animal models of heart failure with preserved ejection fraction

    OpenAIRE

    Conceição, G.; Heinonen, I.; Lourenço, A. P.; Duncker, D. J.; Falcão-Pires, I.

    2016-01-01

    Heart failure with preserved ejection fraction (HFpEF) constitutes a clinical syndrome in which the diagnostic criteria of heart failure are not accompanied by gross disturbances of systolic function, as assessed by ejection fraction. In turn, under most circumstances, diastolic function is impaired. Although it now represents over 50 % of all patients with heart failure, the mechanisms of HFpEF remain understood, precluding effective therapy. Understanding the pathophysiology of HFpEF has be...

  12. Heart Rate Variability Interventions for Concussion and Rehabilitation

    OpenAIRE

    Robert Lake Conder; Conder, Alanna A.

    2014-01-01

    The study of Heart Rate Variability (HRV) has emerged as an essential component of cardiovascular health, as well as a physiological mechanism by which one can increase the interactive communication between the cardiac and the neurocognitive systems (i.e., the body and the brain). It is well-established that lack of heart rate variability implies cardiopathology, morbidity, reduced quality-of-life, and precipitous mortality. On the positive, optimal heart rate variability has been associated ...

  13. Crosstalk between the heart and peripheral organs in heart failure.

    Science.gov (United States)

    Jahng, James Won Suk; Song, Erfei; Sweeney, Gary

    2016-03-11

    Mediators from peripheral tissues can influence the development and progression of heart failure (HF). For example, in obesity, an altered profile of adipokines secreted from adipose tissue increases the incidence of myocardial infarction (MI). Less appreciated is that heart remodeling releases cardiokines, which can strongly impact various peripheral tissues. Inflammation, and, in particular, activation of the nucleotide-binding oligomerization domain-like receptors with pyrin domain (NLRP3) inflammasome are likely to have a central role in cardiac remodeling and mediating crosstalk with other organs. Activation of the NLRP3 inflammasome in response to cardiac injury induces the production and secretion of the inflammatory cytokines interleukin (IL)-1β and IL-18. In addition to having local effects in the myocardium, these pro-inflammatory cytokines are released into circulation and cause remodeling in the spleen, kidney, skeletal muscle and adipose tissue. The collective effects of various cardiokines on peripheral organs depend on the degree and duration of myocardial injury, with systematic inflammation and peripheral tissue damage observed as HF progresses. In this article, we review mechanisms regulating myocardial inflammation in HF and the role of factors secreted by the heart in communication with peripheral tissues.

  14. Forkhead box transcription factors in embryonic heart development and congenital heart disease.

    Science.gov (United States)

    Zhu, Hong

    2016-01-01

    Embryonic heart development is a very complicated process regulated precisely by a network composed of many genes and signaling pathways in time and space. Forkhead box (Fox, FOX) proteins are a family of transcription factors characterized by the presence of an evolutionary conserved "forkhead"or "winged-helix" DNA-binding domain and able to organize temporal and spatial gene expression during development. They are involved in a wide variety of cellular processes, such as cell cycle progression, proliferation, differentiation, migration, metabolism and DNA damage response. An abundance of studies in model organisms and systems has established that Foxa2, Foxc1/c2, Foxh1 and Foxm1, Foxos and Foxps are important components of the signaling pathways that instruct cardiogenesis and embryonic heart development, playing paramount roles in heart development. The previous studies also have demonstrated that mutations in some of the forkhead box genes and the aberrant expression of forkhead box gene are heavily implicated in the congenital heart disease (CHD) of humans. This review primarily focuses on the current understanding of heart development regulated by forkhead box transcription factors and molecular genetic mechanisms by which forkhead box factors modulate heart development during embryogenesis and organogenesis. This review also summarizes human CHD related mutations in forkhead box genes as well as the abnormal expression of forkhead box gene, and discusses additional possible regulatory mechanisms of the forkhead box genes during embryonic heart development that warrant further investigation.

  15. Ischaemic heart disease

    DEFF Research Database (Denmark)

    Hansen, Louise Houlberg; Mikkelsen, Søren

    2013-01-01

    Purpose. Correct prehospital diagnosis of ischaemic heart disease (IHD) may accelerate and improve the treatment. We sought to evaluate the accuracy of prehospital diagnoses of ischemic heart diseases assigned by physicians. Methods. The Mobile Emergency Care Unit (MECU) in Odense, Denmark...

  16. Music and the heart.

    Science.gov (United States)

    Koelsch, Stefan; Jäncke, Lutz

    2015-11-21

    Music can powerfully evoke and modulate emotions and moods, along with changes in heart activity, blood pressure (BP), and breathing. Although there is great heterogeneity in methods and quality among previous studies on effects of music on the heart, the following findings emerge from the literature: Heart rate (HR) and respiratory rate (RR) are higher in response to exciting music compared with tranquilizing music. During musical frissons (involving shivers and piloerection), both HR and RR increase. Moreover, HR and RR tend to increase in response to music compared with silence, and HR appears to decrease in response to unpleasant music compared with pleasant music. We found no studies that would provide evidence for entrainment of HR to musical beats. Corresponding to the increase in HR, listening to exciting music (compared with tranquilizing music) is associated with a reduction of heart rate variability (HRV), including reductions of both low-frequency and high-frequency power of the HRV. Recent findings also suggest effects of music-evoked emotions on regional activity of the heart, as reflected in electrocardiogram amplitude patterns. In patients with heart disease (similar to other patient groups), music can reduce pain and anxiety, associated with lower HR and lower BP. In general, effects of music on the heart are small, and there is great inhomogeneity among studies with regard to methods, findings, and quality. Therefore, there is urgent need for systematic high-quality research on the effects of music on the heart, and on the beneficial effects of music in clinical settings.

  17. Heart failure in COPD

    NARCIS (Netherlands)

    Rutten, Frans Hendrik

    2005-01-01

    The main aim of the thesis was to assess the prevalence of heart failure in patients with a diagnosis of chronic obstructive pulmonary disease (COPD). Furthermore, to explore diagnostic strategies (including natriuretic peptides and cardiovascular magnetic resonance imaging (CMR)) to identify heart

  18. Mapping the Heart

    Science.gov (United States)

    Hulse, Grace

    2012-01-01

    In this article, the author describes how her fourth graders made ceramic heart maps. The impetus for this project came from reading "My Map Book" by Sara Fanelli. This book is a collection of quirky, hand-drawn and collaged maps that diagram a child's world. There are maps of her stomach, her day, her family, and her heart, among others. The…

  19. World Heart Day

    Centers for Disease Control (CDC) Podcasts

    2009-09-01

    For World Heart Day, learn more about what heart-healthy steps you can take in the workplace.  Created: 9/1/2009 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 9/9/2009.

  20. Mechanical ventilation and nutritional support for the treatment of severe valvular heart disease for valve replacement%重症心脏瓣膜置换术后营养支持治疗

    Institute of Scientific and Technical Information of China (English)

    董铭峰; 马增山; 马胜军; 王建堂; 柴守栋; 唐培哲

    2011-01-01

    目的 探讨重症心脏瓣膜置换术患者机械通气和营养支持治疗的临床特点及治疗效果.方法 回顾性分析48例患者经机械通气和营养支持治疗的临床资料.全组采用胃肠外营养(PN)+胃肠内营养(EN)支持3~10 d,第1~3天PN+ EN支持,第4天后完全EN支持,期间监测术前1天、术后第1、3、7天血浆总白蛋白(TP)、血浆白蛋白(ALB)、前白蛋白(PA);CD3+、CD4+、CD8+,计算CD4+/CD8+及血糖变化.结果 术后第7天CD3+、CD4+、CD8+,CD4+/CD8+明显升高(P<0.05或P<0.01);TP、ALB、PA明显增高(P<0.05).合并高血糖6例,消化道出血3例,肺感染2例.36例1次脱机成功,2次脱机成功8例,3次脱机成功4例,无一例依赖呼吸机.结论 机械通气和营养支持治疗重症心脏瓣膜置换术临床效果较好,但应注意营养供给方式的选择.%Objective To investigate the clinical features and effect of the treatment of mechanical ventilation and nutritional support for patients with severe valvular heart disease for valve replacement.Methods The clinical datas of 48 cases treated with mechanical ventilation and nutritional support were retrospectively analyzed.Parenteral + Enteral nutrition support were used in all patients for 3-10 days.For each periphera samples were taken on one day before operation on the first,third and seventh day after opration respective,The percentage subsets including TP,ALB,PA,CD3 +,CD4 +,CD8 + as well as CD4 + / CD8 + were examined.Results It was found that the percentage of TP,ALB,PA,CD3 +,CD4 +,CD8 + as well as CD4 + / CD8 + were significantly increased at seven days after operation (P < 0.05 or P < 0.01 ).Initiation of spontaneously breathing occurred in 36,8 and 4 patients at the first,second and third off-line performance respectively.High blood sugar,gastrointestinal bleeding,lung infection and respiratory failure were found in 6,3 and 2 patients respectively.No patient was found ventilator dependent.Conclusions The

  1. Living with Coronary Heart Disease

    Science.gov (United States)

    ... from the NHLBI on Twitter. Living With Coronary Heart Disease Coronary heart disease (CHD) can cause serious complications. However, if you ... changes and medicines, go to "How Is Coronary Heart Disease Treated?" Work closely with your doctor to control ...

  2. Heart Disease and African Americans

    Science.gov (United States)

    ... Minority Population Profiles > Black/African American > Heart Disease Heart Disease and African Americans Although African American adults are ... were 30 percent more likely to die from heart disease than non-Hispanic whites. African American women are ...

  3. Living with Diabetic Heart Disease

    Science.gov (United States)

    ... from the NHLBI on Twitter. Living With Diabetic Heart Disease Diabetic heart disease (DHD) increases the likelihood of earlier and more ... also tend to have less success from certain heart disease treatments, such as coronary artery bypass grafting and ...

  4. Heart Disease and Stroke Prevention

    Science.gov (United States)

    ... Heart Health and Stroke Heart disease and stroke prevention Related information Learn more about healthy eating and ... top More information on Heart disease and stroke prevention Read more from womenshealth.gov A Lifetime of ...

  5. Adults with Congenital Heart Defects

    Science.gov (United States)

    ... Thromboembolism Aortic Aneurysm More Web Booklet: Adults With Congenital Heart Defects Updated:Apr 24,2014 From the Committee on ... below to learn more. Web Booklet: Adults With Congenital Heart Defects Introduction Introduction: Adults with Congenital Heart Defects Introduction: ...

  6. What Causes Heart Valve Disease?

    Science.gov (United States)

    ... a heart attack or injury to the heart. Rheumatic Fever Untreated strep throat or other infections with strep bacteria that progress to rheumatic fever can cause heart valve disease. When the body ...

  7. Heart Disease and Stroke Statistics

    Science.gov (United States)

    ... Media for Heart.org Heart and Stroke Association Statistics Banner 1 - Stats white banner Each year, the ... health and disease in the population. Heart & Stroke Statistics FAQs What is Prevalence? Prevalence is an estimate ...

  8. The Effects and Mechanism of C-Type Natriuretic Peptides on Swine Heart Coronary Artery%C型利钠肽扩张猪冠状动脉的作用及机制的研究

    Institute of Scientific and Technical Information of China (English)

    舒燕; 李其勇; 姜荣建; 孔洪

    2015-01-01

    Objective Investigate the influences of C-natriuretic peptides on langendorff-perfused swine heart coronary. Reveal the underlying vasodilatory ability and mechanism of C-natriuretic peptides. Methods Three different groups named the C-Natriuretic Group ( CNP Group) , the Nitroglycerol Group ( GTN Group) , and the NPR-C Receptor Agonist Group ( cANF4-23 Group) were set up.①Each of above groups was perfused by solution of NE,and then was perfused by GTN、CNP and cANF4-23. The vasodilatory influences of CNP and GTN on swine heart coronary arteries and whether cANF4-23 were involved in this procedure were studied .②cANF4-28 was given first, and then CNP were added, the vasodilatory influences were observed.③K + solutions ( at the concentration of 80 nM) were used to preserve the arteries, so they were all in contracted state, and then CNP and cANF4-23 were added, and the vasodilatory influences were observed. Results ①CNP,GTN and cANF4-23 all had significant vasodilatory in-fluences on swine heart coronary artery. no significant difference of vasodilation influences was found between CNP Group and cANF4-23 Group(P>0. 05). The vasodilatory influence of CNP Group was weaker than GTN Group (P<0. 05).②In cANF4-28 preserved arteries, The largest circulus vasculosus vasodilatory ratios of CNP was significantly weaker than Control Group , and had statistical significance (P<0. 01).③The vasodilatory influences of CNP and cANF4-23 Groups were significantly decreased in high concentration K + solution in contrast with the Control Group ( P<0. 05 ) , but not blocked. Conclusions C- Natriuretic peptides have significant vasodilatory influence on swine heart coronary artery. The vasodilatory mechanism of CNP involves NPR-C. NPR-C is not only the well-known clearance receptor, but also leads to vasodilation of the coronary artery. the vasodilatory of CNP/NPR-C sig-naling involves K+ channel.%目的:本研究通过离体灌流方法观察C型利钠肽( CNP)对离体

  9. STUDY ON THE RELATIONSHIP AMONG THE HEART MERIDIAN,CARDIAC REFERRED PAIN AND THE HEART

    Institute of Scientific and Technical Information of China (English)

    RONG Peijing; ZHU Bing

    2002-01-01

    @@ Purpose: The referred pain of the somatic structure, a response of the visceralgia, is often seen in clinic. But its underlying mechanisms are poorly understood. It is interested that cardiac referred pain often appears along the running course of the Heart Meridian (HM), while acupuncture of the acupoints of HM can effectively relieve cardiac pain. In the present study, the neural basis of the relationship among the HM, cardiac referred pain and the heart is investigated by using tri-labeling technique.

  10. [Valvular heart disease in women].

    Science.gov (United States)

    Tornos, Pilar

    2006-08-01

    Very few studies of valvular heart disease have been specifically carried out in women. It is well known that the prevalence of some types of valve disease is influenced by sex: rheumatic mitral stenosis is very common in women but degenerative valve disease affects both sexes similarly. A number of sex differences in the physiopathology of degenerative aortic stenosis have been reported: the degree of calcification is less in women than men and women's ventricles respond to equivalent reductions in valve area with a greater increase in gradient and greater contractility. With regard to prognosis, it is generally accepted that mortality associated with heart surgery is higher in women than men, for both coronary artery and valve surgery. The underlying reasons for the increase in mortality are not clear. Pregnancy presents particular difficulties for women with valvular heart disease. In those with significant valve lesions, it is advisable to correct the valve disease before pregnancy is considered. Anticoagulant treatment involves serious problems for pregnant women with a mechanical prosthesis. They suffer increased risks of prosthetic valve thrombosis and of fetal embryopathy if they take oral anticoagulants during the first trimester.

  11. Regulation of the renal sympathetic nerves in heart failure

    Directory of Open Access Journals (Sweden)

    Rohit eRamchandra

    2015-08-01

    Full Text Available Heart failure (HF is a serious debilitating condition with poor survival rates and an increasing level of prevalence. Heart failure is associated with an increase in renal norepinephrine spillover, which is an independent predictor of mortality in HF patients. The excessive sympatho-excitation that is a hallmark of heart failure has long-term effects that contribute to disease progression. An increase in directly recorded renal sympathetic nerve activity has also been recorded in animal models of heart failure. This review will focus on the mechanisms controlling sympathetic nerve activity to the kidney during normal conditions and alterations in these mechanisms during heart failure. In particular the roles of afferent reflexes and central mechanisms will be discussed.

  12. Angioplasty and stent placement - heart

    Science.gov (United States)

    ... angioplasty; Coronary artery angioplasty; Percutaneous transluminal coronary angioplasty; Heart artery dilatation ... to carefully guide the catheter up into your heart and arteries. Dye will be injected into your ...

  13. 心脏机械瓣膜置换术后华法林低强度抗凝疗效观察%Efficacy of warfarin low intense anticoagulation after heart valve replacement

    Institute of Scientific and Technical Information of China (English)

    刘状; 葛圣林; 张成鑫

    2014-01-01

    anticoagulation at the 1st Affiliated Hospital of Anhui Medical University from January 2010 to January 2013 .During the follow-up,we recorded the prothrombin time ( PT) ,international normalized ratio ( INR) and oral war-farin dose and thromboembolism/hemorrhage complications .Results Complete data were obtained of 469 patients which were followed up for an average of 18.13 ±6.02 months (range 1~37 months),totally followed up 1 960.8p-ys.Two hundred and eleven were males and two hundred and fifty-eight were females with a mean age of 40.52 ±13.38 years.A total of 268 patients had MVR,115 patients AVR,and 86 patients DVR.Valves implanted were all bileaflet ,of which 153 were St.Jude Regent,291 CarboMedics,and 111 GKS. Average INR was 2.11 ±0.56,and warfarin dose was (3.124 ±2.4) mg.There were 47 cases of anticoagulation-related complications ,of which 37 were anticoagulation-related hemorrhage (1.89%pt-y),and 10 were anticoagulation-related thromboembolism (0.51%pt-y). And 5 patients died,of which 3 were anticoagulation related .Among all of these patients ,316 were complicated by atrial fibrillation and 43 by left atrial thrombosis .Conclusions Anticoagulation for mechanical heart valve replacement can be managed with INR levels within the range of 1.8~2.2 ,which can prevent hemorrhagic and thromboembolic events .Patients with atrial fibrillation and double valve replace-ment have higher anticoagulation-related morbidity ,which should have higher frequency of review and timely adjustment of warfarin dose .

  14. Mechanical circulatory treatment of advanced heart failure

    DEFF Research Database (Denmark)

    Rujic, Dragana; Sundbøll, Jens; Tofig, Bawer Jalal;

    2016-01-01

    The paroxysmal supraventricular tachycardias (SVT) are commonly encountered arrhythmias and include atrioventricular nodal re-entrant tachycardia, atrioventricular reciprocating tachycardia, and focal atrial tachycardia. These tachycardias share several clinical features as well as similar manage...

  15. A healthy heart is not a metronome: an integrative review of the heart's anatomy and heart rate variability.

    Science.gov (United States)

    Shaffer, Fred; McCraty, Rollin; Zerr, Christopher L

    2014-01-01

    Heart rate variability (HRV), the change in the time intervals between adjacent heartbeats, is an emergent property of interdependent regulatory systems that operate on different time scales to adapt to challenges and achieve optimal performance. This article briefly reviews neural regulation of the heart, and its basic anatomy, the cardiac cycle, and the sinoatrial and atrioventricular pacemakers. The cardiovascular regulation center in the medulla integrates sensory information and input from higher brain centers, and afferent cardiovascular system inputs to adjust heart rate and blood pressure via sympathetic and parasympathetic efferent pathways. This article reviews sympathetic and parasympathetic influences on the heart, and examines the interpretation of HRV and the association between reduced HRV, risk of disease and mortality, and the loss of regulatory capacity. This article also discusses the intrinsic cardiac nervous system and the heart-brain connection, through which afferent information can influence activity in the subcortical and frontocortical areas, and motor cortex. It also considers new perspectives on the putative underlying physiological mechanisms and properties of the ultra-low-frequency (ULF), very-low-frequency (VLF), low-frequency (LF), and high-frequency (HF) bands. Additionally, it reviews the most common time and frequency domain measurements as well as standardized data collection protocols. In its final section, this article integrates Porges' polyvagal theory, Thayer and colleagues' neurovisceral integration model, Lehrer et al.'s resonance frequency model, and the Institute of HeartMath's coherence model. The authors conclude that a coherent heart is not a metronome because its rhythms are characterized by both complexity and stability over longer time scales. Future research should expand understanding of how the heart and its intrinsic nervous system influence the brain.

  16. 畅心饮改善冠心病心肌缺血及其机制初步研究%Changxinyin Decoction for Ameliorating Cardiac Ischemia of Coronary Heart Disease and Its Underlying Mechanisms: A Pilot Clinical Study

    Institute of Scientific and Technical Information of China (English)

    郭炜; 崔松; 金涛

    2011-01-01

    Objective To observe the effects of Changxinyin Decoction (a traditional Chinese medicinemainly composed of coptis, pinellia, snakegourd fruit, salvia miltiorrhiza, earthworm, cassia twig, and astragalus) on angina pectoris, traditional Chinese medicine (TCM) syndromes and cardiac ischemia in coronary heart disease patients, and explore its underlying mechanisms. Methods A total of 66 patients with coronary heart disease were divided into 2 groups. Thirty-two patients in the control group were treated with conventional western therapies; additionally, 34 patients in the treatment group were treated with Changxinyin Decoction.The therapeutic effects of Changxinyin Decoction on angina pectoris and TCM syndromes were observed; and its effects on total ischemic burden (TIB) and body mass index (BMI) as well as the levels of high sensitive C-reactive protein (hs-CRP) and blood lipids, including low density lipoprotein-cholesterol (LDL-C) and total cholesterol (TC), were observed also. Results As compared to conventional western therapies, Changxinyin Decoction could further alleviate angina pectoris, reduce scores of TCM syndromes, and further lower the levels of TIB, hs-CRP,LDL-C, and TC. Conclusion Changxinyin Decoction can alleviate cardiac ischemia; the underlying mechanisms might be related with lowering blood lipids, and inhibiting the inflammation in the coronary artery.%目的 观察畅心饮对冠心病心绞痛与中医证候疗效、心肌缺血的改善作用,并探究其可能机制.方法 将66例冠心病患者分为2组,对照组(32例)按常规西医治疗,治疗组(34例)在常规西医治疗基础上加服畅心饮,观察畅心饮对心绞痛与中医证候的疗效及对缺血总负荷(total ischemic burden,TIB)、体质量指数(body mass index,BMI)、超敏C反应蛋白(high sensitive C-reactive protein,hs-CRP)以及低密度脂蛋白胆固醇(low density lipoprotein-cholesterol,LDL-C )和总胆固醇(total cholesterol,TC)的影响.结果 与对

  17. Renal neurohormonal regulation in heart failure decompensation.

    Science.gov (United States)

    Jönsson, Sofia; Agic, Mediha Becirovic; Narfström, Fredrik; Melville, Jacqueline M; Hultström, Michael

    2014-09-01

    Decompensation in heart failure occurs when the heart fails to balance venous return with cardiac output, leading to fluid congestion and contributing to mortality. Decompensated heart failure can cause acute kidney injury (AKI), which further increases mortality. Heart failure activates signaling systems that are deleterious to kidneys such as renal sympathetic nerve activity (RSNA), renin-angiotensin-aldosterone system, and vasopressin secretion. All three reduce renal blood flow (RBF) and increase tubular sodium reabsorption, which may increase renal oxygen consumption causing AKI through renal tissue hypoxia. Vasopressin contributes to venous congestion through aquaporin-mediated water retention. Additional water retention may be mediated through vasopressin-induced medullary urea transport and hyaluronan but needs further study. In addition, there are several systems that could protect the kidneys and reduce fluid retention such as natriuretic peptides, prostaglandins, and nitric oxide. However, the effect of natriuretic peptides and nitric oxide are blunted in decompensation, partly due to oxidative stress. This review considers how neurohormonal signaling in heart failure drives fluid retention by the kidneys and thus exacerbates decompensation. It further identifies areas where there is limited data, such as signaling systems 20-HETE, purines, endothelin, the role of renal water retention mechanisms for congestion, and renal hypoxia in AKI during heart failure.

  18. Intercellular communication lessons in heart failure.

    Science.gov (United States)

    Bang, Claudia; Antoniades, Charalambos; Antonopoulos, Alexios S; Eriksson, Ulf; Franssen, Constantijn; Hamdani, Nazha; Lehmann, Lorenz; Moessinger, Christine; Mongillo, Marco; Muhl, Lars; Speer, Thimoteus; Thum, Thomas

    2015-11-01

    Cell-cell or inter-organ communication allows the exchange of information and messages, which is essential for the coordination of cell/organ functions and the maintenance of homeostasis. It has become evident that dynamic interactions of different cell types play a major role in the heart, in particular during the progression of heart failure, a leading cause of mortality worldwide. Heart failure is associated with compensatory structural and functional changes mostly in cardiomyocytes and cardiac fibroblasts, which finally lead to cardiomyocyte hypertrophy and fibrosis. Intercellular communication within the heart is mediated mostly via direct cell-cell interaction or the release of paracrine signalling mediators such as cytokines and chemokines. However, recent studies have focused on the exchange of genetic information via the packaging into vesicles as well as the crosstalk of lipids and other paracrine molecules within the heart and distant organs, such as kidney and adipose tissue, which might all contribute to the pathogenesis of heart failure. In this review, we discuss emerging communication networks and respective underlying mechanisms which could be involved in cardiovascular disease conditions and further emphasize promising therapeutic targets for drug development.

  19. Direct myocardial perfusion imaging in valvular heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Soto, R.C.; Durante, M.L.; Villacorta, E.V.; Torres, J.F.; Monzon, O.P.

    1981-02-01

    Twenty two patients with rheumatic valvular heart disease - 21 having a history of heart failure - were studied using direct coronary injection of /sup 99m/Tc labelled MAA particles during the course of hemodynamic and arteriographic studies. Myocardial perfusion deficit patterns have been shown to be consistent or indicative of either patchy, regional or gross ischemia. In patients with history of documented heart failure 90% (18 cases) had ischemic perfusion deficit in the involved ventricle. We conclude that diminished myocardial blood flow is an important mechanism contributing to the development of heart failure.

  20. Isolated heart models: cardiovascular system studies and technological advances.

    Science.gov (United States)

    Olejnickova, Veronika; Novakova, Marie; Provaznik, Ivo

    2015-07-01

    Isolated heart model is a relevant tool for cardiovascular system studies. It represents a highly reproducible model for studying broad spectrum of biochemical, physiological, morphological, and pharmaceutical parameters, including analysis of intrinsic heart mechanics, metabolism, and coronary vascular response. Results obtained in this model are under no influence of other organ systems, plasma concentration of hormones or ions and influence of autonomic nervous system. The review describes various isolated heart models, the modes of heart perfusion, and advantages and limitations of various experimental setups. It reports the improvements of perfusion setup according to Langendorff introduced by the authors.

  1. Anticoagulation property and security of artificial heart valve material

    Institute of Scientific and Technical Information of China (English)

    WANG Xianghui; XU Jingfang; LIU Xianghuai; ZHANG Feng; LI Changrong; YU Liujiang; ZHENG Zhihong; WANG Xi; JIANG Zhenbin; CHEN Anqing

    2005-01-01

    Heart valve diseases threaten human health. One reliable way to save lives of such patients is to replace the pathologically changed heart valves by artificial ones. Over 2 million patients have received LTI-carbon heart valve's implantation. However, the thrombosis after the implantation is one of the difficulties that need to be solved. In order to improve the blood compatibility and security of mechanical heart valves, ion beam technology was used to modify the surface properties of the materials. The investigation results have been summarized in this paper.

  2. [Ischemic heart disease].

    Science.gov (United States)

    Yamamuro, Megumi; Ogawa, Hisao

    2009-04-01

    It has been reported that antihypertensive therapy reduces the risk of ischemic heart disease. Except for the antihypertensive effects, the angiotensin converting enzyme (ACE) inhibitors are proved to be very effective in primary and secondary event onset prophylaxis by many clinical trials. The angiotensin II receptor antagonists (ARBs) used briskly in recent years inhibits angiotensin II type 1 receptor alternatively. Although ARBs protect organs, especially blood vessel, heart, brain and kidney in sites of pharmacology, ARBs are still not much as effective results as ACE inhibitors for the patients with ischemic heart disease, by many clinical trials.

  3. Study on anti-heart failure mechanism of Qiliqiangxin capsule on rats%芪苈强心胶囊抗大鼠心衰的作用机制研究

    Institute of Scientific and Technical Information of China (English)

    张学团

    2016-01-01

    目的::探讨芪苈强心胶囊对心衰大鼠的作用机制。方法:将60只雄性SD大鼠随机抽取10只作为正常对照组,其余50只大鼠腹腔注射阿霉素造成心力衰竭大鼠模型,并随机分为模型对照组,贝那普利组,芪苈强心胶囊低剂量组、中剂量组和高剂量组,每组各10只。正常对照组、模型对照组大鼠给予等剂量蒸馏水;贝那普利组大鼠给予1.43mg/kg盐酸贝那普利;芪苈强心胶囊低剂量组、中剂量组、高剂量组大鼠分别给予芪苈强心胶囊420 mg/kg、840 mg/kg和1680 mg/kg。各组大鼠均连续给药4周后,用超声心动图检测心衰大鼠左心室舒张末内径( LVEDD)和收缩末内径( LVESD),并计算左室短轴缩短率( LVFS)及射血分数( LVEF)。酶联免疫吸附法( ELISA)检测大鼠血液中血管紧张素Ⅱ(AngⅡ)、脑钠肽(BNP)、心肌肌钙蛋白I(cTnI)和醛固酮(ALD)的水平。结果:芪苈强心胶囊能够明显降低心衰大鼠的 LVESD、LVEDD、AngⅡ、BNP、cTnI和ALD的水平(P<0.05),升高LVEF和LVFS(P<0.05);中剂量效果较佳。结论:芪苈强心胶囊能改善心衰大鼠心舒张功能,经抑制RAAS系统调节神经内分泌,改善心衰症状。%Objective:To investigate anti-heart failure mechanism of Qiliqiangxin capsule on rats. Methods:60 male SD rats were selected, wherein 10 rats were used as normal control group, and the other 50 rats were intraperitoneally injected with Adriamycin to establish the heart failure rat models. Then, these rat models were randomly divided into model control group, Benazepril group, and Qiliqiangxin capsule low-dose group, medium-dose group and high-dose group with 10 rats in each group. The normal control group and model control group were given the equivalent dose distilled water; the Benazepril group was given 1. 43mg/kg Benazepril hydro-chloride;and the Qiliqiangxin capsule low-dose group, medium-dose group and high-dose group were given 420

  4. Depressive symptoms are related to decreased low-frequency heart rate variability in older adults with decompensated heart failure

    NARCIS (Netherlands)

    Guinjoan, Salvador M.; Castro, Mariana N.; Vigo, Daniel E.; Weidema, Hylke; Berbara, Carlos; Fahrer, Rodolfo D.; Grancelli, Hugo; Nogues, Martin; Leiguarda, Ramon C.; Cardinali, Daniel P.

    2007-01-01

    Background/Aims: Depression has been associated with increased mortality among individuals with heart failure, but the mechanism for this association is unsettled. Depression is often found to result in autonomic dysfunction which, if present in heart failure, might help explain worsened outcomes. M

  5. Heart to Heart Art: Empowering Homeless Children and Youth

    Science.gov (United States)

    Shepard, Jerri; Booth, Deborah

    2009-01-01

    This article describes Heart to Heart Art, an after-school program developed for homeless children and youth at the YWCA in Spokane, Washington. Pre-service teacher candidates from a local university create meaningful activities that engage homeless students in visual art, music, drama, cooking, and community service. Heart to Heart Art was…

  6. Postextrasystolic potentiation in the isolated rat heart

    NARCIS (Netherlands)

    Meijler, F.L.; Boogaard, F. van de; Tweel, H. van der; Durrer, D.

    1962-01-01

    “Postextrasystolic potentiation" of isotonic contractions of the intact isolated rat heart was studied. It was found that the Frank-Starling mechanism does not participate in the increase of the contraction following a premature beat and a compensatory pause. A linear relationship could be demonstra

  7. Deteriorated function of cutaneous microcirculation in chronic congestive heart failure

    Institute of Scientific and Technical Information of China (English)

    Marie-Louise Edvinsson; Erik Uddman; Sven E Andersson

    2011-01-01

    Background Chronic congestive heart failure is a complex condition that leads to dysfunction in the peripheral microcirculation. We have previously shown that vascular reactivity is reduced with increasing age.In this study,we examined a group of very old patients with severe chronic heart failure to test the hypothesis that vascular function is further compromised by a combination of heart failure and aging.Methods Cutaneous forearm blood flow was measured by laser Doppler flownretry and compared among three groups:Group 1 (n=20,men±SE:85.54 years),heart failure patients with New York Heart Association class Ⅳ(NYHA IV) and with a NT-proBNP level =10,mean±SE:67.6 ± 3.0 years),healthy controls with no clinical signs of heart failure.The vasodilator response to the iontophoretic administration of acetylcholine (ACh),acting via an endothelial mechanism,and sodium nitroprusside (SNP),acting via a smooth muscle cell mechanism,were studied. Results All patients with heart failure had significantly reduced vascular reactivity independent of the mode of stimulation (ACh,SNP or heat) when compared to healthy controls.However,the responses did not differ between the two groups of heart failure patients.Conclusions Cutaneous vascular reactivity is reduced in heart failure patients and does not correlate with the severity of the condition or age of patients.

  8. Heart Procurement from a Donor on Venovenous ECMO Support.

    Science.gov (United States)

    Singh, Gopal; Tsukashita, Masaki; Biscotti, Mauer; Costa, Joseph; Lambert, Daniel; Bacchetta, Matthew; Takayama, Hiroo

    2016-01-01

    We report the case of a 37-year-old woman with acute respiratory distress syndrome and became a candidate for organ donation after anoxic brain injury and was on a venovenous extracorporeal membrane oxygenation (VV-ECMO) support. On preoperative evaluation and gross examination, the donor's heart was acceptable for heart transplantation to a 62-year-old female patient with a history of nonischemic cardiomyopathy with a HeartMate II mechanical assist device. Orthotopic heart transplantation was successfully performed in the recipient. We report a case that suggests that the procurement of a heart from a donor on ECMO support can potentially expand the donor heart pool in carefully selected patients.

  9. Genome-wide association studies and resting heart rate

    DEFF Research Database (Denmark)

    Oskari Kilpeläinen, Tuomas

    2016-01-01

    Genome-wide association studies (GWASs) have revolutionized the search for genetic variants regulating resting heart rate. In the last 10 years, GWASs have led to the identification of at least 21 novel heart rate loci. These discoveries have provided valuable insights into the mechanisms...... and pathways that regulate heart rate and link heart rate to cardiovascular morbidity and mortality. GWASs capture majority of genetic variation in a population sample by utilizing high-throughput genotyping chips measuring genotypes for up to several millions of SNPs across the genome in thousands...... of individuals. This allows the identification of the strongest heart rate associated signals at genome-wide level. While GWASs provide robust statistical evidence of the association of a given genetic locus with heart rate, they are only the starting point for detailed follow-up studies to locate the causal...

  10. ST2 IN REJECTION OF THE TRANSPLANTED HEART

    Directory of Open Access Journals (Sweden)

    O. P. Shevchenko

    2015-01-01

    Full Text Available This review summarizes the current literature devoted to the analysis of prognostic role of ST2 biomarker in rejection of the transplanted heart. ST2 is one of the most promising diagnostic markers of the development and severity of heart failure as well as the mortality risk in patients with cardiovascular diseases. ST2 is expressed in cardiomyocytes in response to a variety of pathological processes and mechanical damage to the heart, which allows diagnosing cardiovascular diseases before clinical manifestations. Presumably, measuring the level of ST2 in heart transplant may have diagnostic and prognostic value in the assessment of graft and risk of rejection. Currently, accumulated clinical data on the role of given biomarker in heart transplantation are not enough, and further research on the relation of ST2 levels with different clinical and laboratory parameters in heart recipients is necessary. 

  11. Data and Statistics: Women and Heart Disease

    Science.gov (United States)

    ... Pressure Salt Cholesterol Million Hearts® WISEWOMAN Women and Heart Disease Fact Sheet Recommend on Facebook Tweet Share Compartir ... Atlas of Heart Disease Facts on Women and Heart Disease Heart disease is the leading cause of death ...

  12. Apoptosis and congestive heart failure.

    Science.gov (United States)

    Feuerstein, G; Ruffolo, R R; Yue, T L

    1997-10-01

    Congestive heart failure (CHF) is the final clinical manifestation of a variety of cardiac (myopathies), coronary (atherosclerosis), and systemic diseases (diabetes, hypertension). Regardless of the origin of the cardiac insult, left ventricular dysfunction resulting in decreased cardiac output elicits a series of adaptational processes that attempt to compensate for some of the decrement in myocardial function. One of the key manifestations of these compensatory processes is cardiac hypertrophy, which is characterized by a marked increase in myocyte size and an increase in contractile proteins. The benefits resulting from these compensatory adaptational mechanisms, however, are only transient, and within a period of months to years, the changes induced in the myocardium fail to sustain cardiac output at a level that is sufficient to meet the demands of the body; subsequently, physical performance is impaired. Typically, progressive dilation and thinning of the left ventricle occur along with progression of CHF. The mechanisms responsible for the thinning of ventricular tissue and loss of left ventricular mass are poorly understood; traditionally, such loss has been attributed to tissue necrosis based on the morphologic observation of dead cardiac myocytes. Very recently, there have been data suggesting that apoptosis, a form of programmed cell death (PCD), occurs in the heart and may be responsible, at least in part, for the progression of CHF and the chronic loss of left ventricular function and mass. Evidence for a role of apoptosis/PCD in the progression of heart failure has been obtained from a variety of observations, including in vitro studies of cardiac myocytes in culture, experimental animal models of cardiac injury, and cardiac tissue obtained from patients with CHF. Thus, apoptosis/PCD may be a critical mechanism involved in the progressive loss of cardiac myocytes, which ultimately results in end-stage heart failure. In this brief review, the evidence

  13. Heart Surgery Terms

    Science.gov (United States)

    ... Patients Choosing Wisely® Adult Cardiac Surgery What is Pediatric Heart Disease? What is Risk Adjustment? Valve Repair/Replacement Surgery Esophageal Surgery Lung/Thoracic Surgery Aneurysm Surgery Arrhythmia Surgery Other Types of Surgery Clinical ...

  14. Heart PET scan

    Science.gov (United States)

    ... nuclear medicine scan; Heart positron emission tomography; Myocardial PET scan ... A PET scan requires a small amount of radioactive material (tracer). This tracer is given through a vein (IV), ...

  15. Types of Heart Surgery

    Science.gov (United States)

    ... from the NHLBI on Twitter. Types of Heart Surgery Coronary Artery Bypass Grafting Coronary artery bypass grafting ( ... TAHs) might be used to treat these patients. Surgery To Place Ventricular Assist Devices or Total Artificial ...

  16. Heart disease and diet

    Science.gov (United States)

    ... liver, and prepared meats such as sausage, hot dogs, and high-fat lunch meats. Adults should eat ... risk: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. ...

  17. Heart and vascular services

    Science.gov (United States)

    ... CT angiography (CTA) and magnetic resonance angiography (MRA) Echocardiogram PET scan of the heart Stress tests (many ... most cases, such procedures do not need general anesthesia . Patients often do not need to stay in ...

  18. Hyperkalemia in Heart Failure.

    Science.gov (United States)

    Sarwar, Chaudhry M S; Papadimitriou, Lampros; Pitt, Bertram; Piña, Ileana; Zannad, Faiez; Anker, Stefan D; Gheorghiade, Mihai; Butler, Javed

    2016-10-01

    Disorders of potassium homeostasis can potentiate the already elevated risk of arrhythmia in heart failure. Heart failure patients have a high prevalence of chronic kidney disease, which further heightens the risk of hyperkalemia, especially when renin-angiotensin-aldosterone system inhibitors are used. Acute treatment for hyperkalemia may not be tolerated in the long term. Recent data for patiromer and sodium zirconium cyclosilicate, used to treat and prevent high serum potassium levels on a more chronic basis, have sparked interest in the treatment of hyperkalemia, as well as the potential use of renin-angiotensin-aldosterone system inhibitors in patients who were previously unable to take these drugs or tolerated only low doses. This review discusses the epidemiology, pathophysiology, and outcomes of hyperkalemia in heart failure; provides an overview of traditional and novel ways to approach management of hyperkalemia; and discusses the need for further research to optimally treat heart failure.

  19. Heart CT scan

    Science.gov (United States)

    ... stored, viewed on a monitor, or printed on film. 3D or three-dimensional models of the heart ... Cardiology, Harborview Medical Center, University of Washington Medical School, Seattle, WA. Also reviewed by David Zieve, MD, ...

  20. Picturing the Heart

    Science.gov (United States)

    ... Links for Students Glossary Picturing the Heart SCIENCE EDUCATION Science Topics Resource Links for General Public Resource Links for Parents/Teachers Resource Links for Students Glossary Government Resources Kids.gov – Science Information and services on the web ...

  1. Heart disease. Third edition

    Energy Technology Data Exchange (ETDEWEB)

    Braunwald, E.

    1988-01-01

    This book contains 62 chapters. Some of the chapter titles are: Radiological and Angiographic Examination of the Heart; Newer Cardiac Imaging Techniques: Digital Subtraction Angiography, Computerized Tomography, Magnetic Resonance Imaging; Nuclear Cardiology; and Genetics and Cardiovascular Disease.

  2. Heart attack - discharge

    Science.gov (United States)

    ... nih.gov/pubmed/23166211 . Giugliano RP, Cannon CP, Braunwald E. Non-ST elevation acute coronary syndromes. In: Mann DL, Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of ...

  3. Advanced Heart Failure

    Science.gov (United States)

    ... patients and their doctors, making good decisions requires teamwork. Through shared decision making, doctors and patients consider ... Heart Failure and Knowing Your Options Planning Ahead Communicating With Your Healthcare Provider Overcoming Barriers to Shared ...

  4. Heart Healthy Eating

    Science.gov (United States)

    ... of heart disease and stroke? You should limit: Saturated fats. Saturated fat is usually in pizza, ice cream, fried chicken, ... and hamburgers. Check the Nutrition Facts label for saturated fat. Less than 10% of your daily calories should ...

  5. Heart Transplantation in Congenital Heart Disease: In Whom to Consider and When?

    Directory of Open Access Journals (Sweden)

    Christine H. Attenhofer Jost

    2013-01-01

    Full Text Available Due to impressive improvements in surgical repair options, even patients with complex congenital heart disease (CHD may survive into adulthood and have a high risk of end-stage heart failure. Thus, the number of patients with CHD needing heart transplantation (HTx has been increasing in the last decades. This paper summarizes the changing etiology of causes of death in heart failure in CHD. The main reasons, contraindications, and risks of heart transplantation in CHD are discussed and underlined with three case vignettes. Compared to HTx in acquired heart disease, HTx in CHD has an increased risk of perioperative death and rejection. However, outcome of HTx for complex CHD has improved over the past 20 years. Additionally, mechanical support options might decrease the waiting list mortality in the future. The number of patients needing heart-lung transplantation (especially for Eisenmenger’s syndrome has decreased in the last years. Lung transplantation with intracardiac repair of a cardiac defect is another possibility especially for patients with interatrial shunts. Overall, HTx will remain an important treatment option for CHD in the near future.

  6. STUDY ON THE RELATIONSHIP AMONG THE HEART MERIDIAN,CARDIAC REFERRED PAIN AND THE HEART

    Institute of Scientific and Technical Information of China (English)

    RONGPeijing; ZHUBing

    2002-01-01

    Purpose:The referred pain of the somatic structure,a response of the visceralgia,is often seen in clinic.But ist underlying mechanisms are poorly understood.It is interested that cardiac referred pain ofter appears along the running course of the Heart Meridian(HM),while acupuncture of the acupoints of HM can effectively relieve cardiac pain.In the present study,the neural basis of the relationship among the HM,cardiac referred pain and the heart is investigated by using tri-labeling technique.Methods:Wistar rats are used in the present study.Three fluorescent dyes,fast blue(FB),propidium lodide(PI) and bibenzimide(Bb)are respectively injected into the pericardial sac,the left and right medial-middle band (HM) or lateral sides[rung Meridian(LM),used for control] of the rat forearms.Results:Examination of the sections of the dorsal ganglions shows that more doubly labeled neurons are found in the ipsilateral dorsal root ganglions of C8-T3 nerve segments from HM and the heart,while fewer double-labeled neurons found from LM and the heart.The facts provide direct evidence for existence of dichotomizing fibers of the ganglion neurons.There exists a relative specific connection between the HM and the heart.It also provides a morphological explanation for cardiogenic referred pain and for the specific interrelation between the heart Meridian and the heart of traditional Chinese medicine.

  7. Mercury Exposure and Heart Diseases

    Directory of Open Access Journals (Sweden)

    Giuseppe Genchi

    2017-01-01

    Full Text Available Environmental contamination has exposed humans to various metal agents, including mercury. It has been determined that mercury is not only harmful to the health of vulnerable populations such as pregnant women and children, but is also toxic to ordinary adults in various ways. For many years, mercury was used in a wide variety of human activities. Nowadays, the exposure to this metal from both natural and artificial sources is significantly increasing. Recent studies suggest that chronic exposure, even to low concentration levels of mercury, can cause cardiovascular, reproductive, and developmental toxicity, neurotoxicity, nephrotoxicity, immunotoxicity, and carcinogenicity. Possible biological effects of mercury, including the relationship between mercury toxicity and diseases of the cardiovascular system, such as hypertension, coronary heart disease, and myocardial infarction, are being studied. As heart rhythm and function are under autonomic nervous system control, it has been hypothesized that the neurotoxic effects of mercury might also impact cardiac autonomic function. Mercury exposure could have a long-lasting effect on cardiac parasympathetic activity and some evidence has shown that mercury exposure might affect heart rate variability, particularly early exposures in children. The mechanism by which mercury produces toxic effects on the cardiovascular system is not fully elucidated, but this mechanism is believed to involve an increase in oxidative stress. The exposure to mercury increases the production of free radicals, potentially because of the role of mercury in the Fenton reaction and a reduction in the activity of antioxidant enzymes, such as glutathione peroxidase. In this review we report an overview on the toxicity of mercury and focus our attention on the toxic effects on the cardiovascular system.

  8. Mercury Exposure and Heart Diseases

    Science.gov (United States)

    Genchi, Giuseppe; Sinicropi, Maria Stefania; Carocci, Alessia; Lauria, Graziantonio; Catalano, Alessia

    2017-01-01

    Environmental contamination has exposed humans to various metal agents, including mercury. It has been determined that mercury is not only harmful to the health of vulnerable populations such as pregnant women and children, but is also toxic to ordinary adults in various ways. For many years, mercury was used in a wide variety of human activities. Nowadays, the exposure to this metal from both natural and artificial sources is significantly increasing. Recent studies suggest that chronic exposure, even to low concentration levels of mercury, can cause cardiovascular, reproductive, and developmental toxicity, neurotoxicity, nephrotoxicity, immunotoxicity, and carcinogenicity. Possible biological effects of mercury, including the relationship between mercury toxicity and diseases of the cardiovascular system, such as hypertension, coronary heart disease, and myocardial infarction, are being studied. As heart rhythm and function are under autonomic nervous system control, it has been hypothesized that the neurotoxic effects of mercury might also impact cardiac autonomic function. Mercury exposure could have a long-lasting effect on cardiac parasympathetic activity and some evidence has shown that mercury exposure might affect heart rate variability, particularly early exposures in children. The mechanism by which mercury produces toxic effects on the cardiovascular system is not fully elucidated, but this mechanism is believed to involve an increase in oxidative stress. The exposure to mercury increases the production of free radicals, potentially because of the role of mercury in the Fenton reaction and a reduction in the activity of antioxidant enzymes, such as glutathione peroxidase. In this review we report an overview on the toxicity of mercury and focus our attention on the toxic effects on the cardiovascular system. PMID:28085104

  9. Interplay between cardiac function and heart development.

    Science.gov (United States)

    Andrés-Delgado, Laura; Mercader, Nadia

    2016-07-01

    Mechanotransduction refers to the conversion of mechanical forces into biochemical or electrical signals that initiate structural and functional remodeling in cells and tissues. The heart is a kinetic organ whose form changes considerably during development and disease. This requires cardiomyocytes to be mechanically durable and able to mount coordinated responses to a variety of environmental signals on different time scales, including cardiac pressure loading and electrical and hemodynamic forces. During physiological growth, myocytes, endocardial and epicardial cells have to adaptively remodel to these mechanical forces. Here we review some of the recent advances in the understanding of how mechanical forces influence cardiac development, with a focus on fluid flow forces. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Integration of Developmental and Environmental Cues in the Heart edited by Marcus Schaub and Hughes Abriel.

  10. Novel therapies in heart failure

    NARCIS (Netherlands)

    Liu, Licette Cécile Yang

    2016-01-01

    Heart failure is a clinical condition that is characterized by the inability of the heart to meet the oxygen requirements of peripheral tissues and organs, despite normal filling pressures. Despite recent developments in the treatment of heart failure, the prognosis of heart failure patients remains

  11. Congenital Heart Defects (For Parents)

    Science.gov (United States)

    ... Old Feeding Your 1- to 2-Year-Old Congenital Heart Defects KidsHealth > For Parents > Congenital Heart Defects A A A What's in this article? How ... a Problem en español Anomalías cardíacas congénitas A congenital heart defect is a problem in the heart's structure that ...

  12. Heart rate response to breathing

    DEFF Research Database (Denmark)

    Mehlsen, J; Pagh, K; Nielsen, J S

    1987-01-01

    Heart rate responses to stepwise and periodic changes in lung volume were studied in seven young healthy males. Stepwise inspiration and expiration both resulted in an increase in heart rate followed by a rapid decrease in heart rate. The fastest heart rate was reached in 1.6 +/- 0.5 s and in 3.6...

  13. Risks for Heart Disease & Stroke

    Science.gov (United States)

    ... for Heart Disease & Stroke Risks for Heart Disease & Stroke About 1.5 million heart attacks and strokes happen every year in the United States. You ... some of your risks for heart disease and stroke, but you can manage many of your risks ...

  14. Community - based Rehabilitation and Health Management in Patients with Mechanical Heart Valve Replacement%人工机械瓣膜置换术后患者的社区康复管理

    Institute of Scientific and Technical Information of China (English)

    胡丕; 余舜; 胡知朋

    2014-01-01

    Objective To explore the significance of community - based rehabilitation and health management in pre-venting and treating long - term complications after mechanical heart valve replacement, Methods During February 2001 to July 2012,83 prosthetic valve implanted patients were included and their health archives were established, All the patients included were given health education,periodic physical examination and complication diagnosis and treatment, Results Follow - up to May 1st,2013,of the 83 patients,no one died of valve disease or complications but three patients(3, 6% )died of lung canc-er,trauma and gastric cancer respectively;79 patients(95, 2% )reached the presupposed anticoagulation standard;8 patients (9, 6% )experienced hemorrhagic tendency and one patient were diagnosed as encephalorrhagia by using MRI;3 patients (3, 6% )were diagnosed as cardiac function NAHY grade Ⅱ and their heart failure was induced by pneumonia,anemia and over-work respectively,but no cardiac shock occurred;3 patients(3, 6% )were diagnosed as atrial fibrillation for the first time and 2 patients(2, 4% )experienced worsened atrial fibrillation that obviously influenced haemodynamics;One patient(1, 2% )ex-perienced ventricular arrhythmias following the infective endocarditis, Conclusion Community - based rehabilitation and health management is of great significance for preventing and treating the long - term complications after prosthetic valve replacement.%目的:探讨社区康复管理在防治人工机械瓣膜置换术后患者远期并发症中的意义。方法2001年2月—2012年7月,共计83例金属瓣膜置换患者在杨柳湾镇中心卫生院建立健康档案,接受系统的健康宣教、定期体检、并发症判断和处理。结果随访至2013-05-01,本组患者死亡3例(3,6%),死亡原因为肺癌、创伤、胃癌各1例,无一例因心脏瓣膜病或相关并发症死亡;总抗凝达标人数79例(95,2%);出血倾向8例(9,6%

  15. [Heart failure and comorbidities].

    Science.gov (United States)

    Boully, Clémence; Hanon, Olivier

    2015-03-01

    Heart failure is a frequent disease in the elderly. Its clinical presentation is less typical and the prognosis more severe than in younger subjects because heart failure occurs in patients with multiple comorbidities. A comprehensive geriatric assessment should therefore be performed to detect the vulnerabilities and manage the comorbidities. The main diseases associated with heart failure are dementia, depression, malnutrition, atrial fibrillation, coronary artery disease, orthostatic hypotension, renal failure, anemia and iron deficiency. Comorbidities worsen heart failure and makes its treatment more difficult. The identification and treatment of comorbidities improve the prognosis in terms of mortality but especially in terms of quality of life. Caution with drugs is necessary because of pharmacokinetic or pharmacodynamic changes related to aging and the comorbidities. In this context, clinical and laboratory monitoring should be increased, mostly during an acute event (acute heart failure, infection, dehydration, fall, new therapy…). Therefore, the follow-up of elderly patients with heart failure requires a multidisciplinary approach that involves close cooperation between cardiologists, geriatricians, general practitioners, nurses, and pharmacists.

  16. Mitochondrial dysfunction in heart failure.

    Science.gov (United States)

    Rosca, Mariana G; Hoppel, Charles L

    2013-09-01

    Heart failure (HF) is a complex chronic clinical syndrome. Energy deficit is considered to be a key contributor to the development of both cardiac and skeletal myopathy. In HF, several components of cardiac and skeletal muscle bioenergetics are altered, such as oxygen availability, substrate oxidation, mitochondrial ATP production, and ATP transfer to the contractile apparatus via the creatine kinase shuttle. This review focuses on alterations in mitochondrial biogenesis and respirasome organization, substrate oxidation coupled with ATP synthesis in the context of their contribution to the chronic energy deficit, and mechanical dysfunction of the cardiac and skeletal muscle in HF. We conclude that HF is associated with decreased mitochondrial biogenesis and function in both heart and skeletal muscle, supporting the concept of a systemic mitochondrial cytopathy. The sites of mitochondrial defects are located within the electron transport and phosphorylation apparatus and differ with the etiology and progression of HF in the two mitochondrial populations (subsarcolemmal and interfibrillar) of cardiac and skeletal muscle. The roles of adrenergic stimulation, the renin-angiotensin system, and cytokines are evaluated as factors responsible for the systemic energy deficit. We propose a cyclic AMP-mediated mechanism by which increased adrenergic stimulation contributes to the mitochondrial dysfunction.

  17. Bio-artificial heart as ultimate treatment of end-stage heart failure.

    Science.gov (United States)

    Smit, Francis E; Dohmen, Pascal M

    2014-10-16

    End-stage heart failure is a major health problem, but implementation of guidelines and optimizing medical therapy for this devastating disease should decrease mortality. If optimal conservative therapy is no longer sufficient, a mechanical support system may be required as final destination therapy or as bridge-to-transplant. Since the first heart transplantation in 1967, this therapy has become the criterion standard for end-stage heart failure, but is limited due to organ shortage. Tissue engineering could help overcome this limitation and provide regeneration, remodeling, and growth potential. This so-called bio-artificial heart would be available, created by a decellularized extracellular matrix and seeded with in vitro proliferated autologous cardiovascular cells. Results of the first experimental studies have been promising, but numerous challenges must be met before this procedure will be available.

  18. Machines versus medication for biventricular heart failure: focus on the total artificial heart.

    Science.gov (United States)

    Arabia, Francisco A; Moriguchi, Jaime D

    2014-09-01

    The medical/surgical management of advanced heart failure has evolved rapidly over the last few decades. With better understanding of heart failure pathophysiology, new pharmacological agents have been introduced that have resulted in improvements in survival. For those patients that fail to improve, mechanical circulatory support with left ventricular assist devices and total artificial hearts (TAHs) have served as a beneficial bridge to transplantation. The TAH has continued to play a significant role as a bridge to transplantation in patients with biventricular failure and more selected indications that could not be completely helped with left ventricular assist devices. Improved survival with the TAH has resulted in more patients benefiting from this technology. Improvements will eventually lead to a totally implantable device that will permanently replace the failing human heart.

  19. A novel approach in cross-linking of bioprosthetic heart valves

    NARCIS (Netherlands)

    Everaerts, Fransiscus Joannes Leonardus

    2007-01-01

    Due to some form of heart valve disease, approximately 250000 patients worldwide undergo surgery to receive a new heart-valve each year. In about 70% of the cases a mechanical heart valve is used despite the fact that permanent anticoagulant therapy for the patient is required. The remaining 30% of

  20. Genomic and nongenomic effects of aldosterone in the rat heart : why is spironolactone cardioprotective?

    NARCIS (Netherlands)

    Chai, WX; Garrelds, IM; Arulmani, U; Schoemaker, RG; Lamers, JMJ; Danser, AHJ

    2005-01-01

    1 Mineralocorticoid receptor (MR) antagonism with spironolactone reduces mortality in heart failure on top of ACE inhibition. To investigate the underlying mechanism, we compared the actions of both aldosterone and spironolactone to those of angiotensin (Ang) II in the rat heart. 2 Hearts of male Wi

  1. [EFFICIENCY OF COMBINATION OF ROFLUMILAST AND QUERCETIN FOR CORRECTION OXYGEN- INDEPENDENT MECHANISMS AND PHAGOCYTIC ACTIVITY OF MACROPHAGE CELLS OF PATIENTS WITH ACUTE EXACERBATION OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE WHEN COMBINED WITH CORONARY HEART DISEASE].

    Science.gov (United States)

    Gerych, P; Yatsyshyn, R

    2015-01-01

    Studied oxygen independent reaction and phagocytic activity of macrophage cells of patients with chronic obstructive pulmonary disease (COPD) II-III stage when combined with coronary heart disease (CHD). The increasing oxygen independent reactions monocytes and neutrophils and a decrease of the parameters that characterize the functional state of phagocytic cells, indicating a decrease in the functional capacity of macrophage phagocytic system (MPS) in patients with acute exacerbation of COPD, which runs as its own or in combination with stable coronary heart disease angina I-II. FC. Severity immunodeficiency state in terms of cellular component of nonspecific immunity in patients with acute exacerbation of COPD II-III stage in conjunction with the accompanying CHD increases with the progression of heart failure. Inclusion of basic therapy of COPD exacerbation and standard treatment of coronary artery disease and drug combinations Roflumilastand quercetin causes normalization of phagocytic indices MFS, indicating improved immune status and improves myocardial perfusion in terms of daily ECG monitoring.

  2. The aging heart.

    Science.gov (United States)

    Klausner, S C; Schwartz, A B

    1985-02-01

    Pathologic studies of the myocardium and valvular structures have failed to provide convincing evidence of gross or microscopic changes that can be ascribed to aging alone. Lipofuscin accumulation and basophilic degeneration in cardiac muscle cells appear to be the most consistent findings associated with aging, but they are found in other conditions. Without doubt, pathologic changes in the myocardium, valves, and coronary arteries are found more frequently in the hearts of elderly persons, but those changes are caused by disease processes associated with an aging population rather than the aging process itself. Both the sinus and atrioventricular nodes decrease in size with age owing to a loss of cellularity. These structures become infiltrated with collagen, elastic tissue, and reticular fibers. Some have found infiltration also with fat. Amyloid deposition, basophilic degeneration of cells, and lipofuscin accumulation occur but probably do not cause functional abnormalities. Similar but less dramatic changes occur in the bundle of His and individual bundle branches. Most of the data suggests that these aging changes are not due to vascular insufficiency. Age-related changes in intrinsic mechanical function have been identified as a prolongation of contraction duration, decreased inotropic responses to catecholamines and cardiac glycosides, and an increase in mechanical refractoriness. Other possible age-related changes include alterations in relaxation, which may or may not be independent of the prolongation of contraction, and changes in the viscoelastic properties of cardiac muscle. When examined in the context of the components of a model of excitation-contraction coupling, changes in action potential duration and the function of the sarcoplasmic reticulum emerge as the most likely bases for the changes. The electrical characteristics of sinus, atrioventricular, and His-Purkinje cells as well as atrial and ventricular muscle cells change with age. The sinus

  3. 1例心脏病术后患者华法林抗凝治疗的用药分析%Analysis of Anticoagulant Therapy for a Patient after Mechanical Heart Valve Replacement

    Institute of Scientific and Technical Information of China (English)

    吴晓丽; 周玲

    2015-01-01

    1例46岁男性患者,既往有房颤及脑梗塞病史,二尖瓣机械瓣膜置换术后予以华法林抗凝治疗。根据药物基因检测及合并用药情况,初始给予华法林2.5 mg po qd,监测INR值偏低,华法林调整至3.75 mg po qd后出院,一月后复查INR 1.64。在随访过程中,临床药师发现该患者出院后自2014年10月至2015年1月,华法林剂量上调,但抗凝效果不佳,有栓塞风险。经详细了解后,考虑与患者服药依从性差相关,建议家属严格监督患者每日按时按量服用华法林,在饮食上避免长期摄入大量含有维生素K的食物并戒酒,一周后复查INR为1.46,接近合适范围。%A 46-year-old male patient, who has a history of atrial fibrillation and cerebral infarction, has taken warfarin-anticoagulant therapy after mechanical heart valve replacement. According to the results of drug genetic testing and drug combination, an abnormal low international standardization ration (INR) was observed when the initial warfarin dosage was 2.5 mg po qd, which indicated the risk of thrombosis. The warfarin dosage was adjusted to 3.75 mg po qd as the patient left hospital and then INR was 1.64 when rechecked one month later. At follow-up, with the increasing dosage of warfarin, the anticoagulant effect was not satisfactory from October 2014 to January 2015. After the detailed investigation, the clinical pharmacists considered the unsatisfactory anticoagulant effect was related to the poor compliance of the patient. The family dependents of the patient were advised to strictly supervise the patient to take warfarin timely and quantitatively and the patient was exhorted to avoid long-term foods with large amounts of vitamin K and forbear from alcohols. INR was 1.46 when rechecked one week later, which was close to the target range.

  4. Theory of heart biomechanics, biophysics, and nonlinear dynamics of cardiac function

    CERN Document Server

    Hunter, Peter; McCulloch, Andrew

    1991-01-01

    In recent years there has been a growth in interest in studying the heart from the perspective of the physical sciences: mechanics, fluid flow, electromechanics. This volume is the result of a workshop held in July 1989 at the Institute for Nonlinear Sciences at the University of California at San Diego that brought together scientists and clinicians with graduate students and postdoctoral fellows who shared an interest in the heart. The chapters were prepared by the invited speakers as didactic reviews of their subjects but also include the structure, mechanical properties, and function of the heart and the myocardium, electrical activity of the heart and myocardium, and mathematical models of heart function.

  5. Remodeling in the ischemic heart: the stepwise progression for heart

    Directory of Open Access Journals (Sweden)

    J.G. Mill

    2011-09-01

    Full Text Available Abstract Coronary artery disease is the leading cause of death in the developed world and in developing countries. Acute mortality from acute myocardial infarction (MI has decreased in the last decades. However, the incidence of heart failure (HF in patients with healed infarcted areas is increasing. Therefore, HF prevention is a major challenge to the health system in order to reduce healthcare costs and to provide a better quality of life. Animal models of ischemia and infarction have been essential in providing precise information regarding cardiac remodeling. Several of these changes are maladaptive, and they progressively lead to ventricular dilatation and predispose to the development of arrhythmias, HF and death. These events depend on cell death due to necrosis and apoptosis and on activation of the inflammatory response soon after MI. Systemic and local neurohumoral activation has also been associated with maladaptive cardiac remodeling, predisposing to HF. In this review, we provide a timely description of the cardiovascular alterations that occur after MI at the cellular, neurohumoral and electrical level and discuss the repercussions of these alterations on electrical, mechanical and structural dysfunction of the heart. We also identify several areas where insufficient knowledge limits the adoption of better strategies to prevent HF development in chronically infarcted individuals.

  6. Electrical Heart Defibrillation with Ion Channel Blockers

    Science.gov (United States)

    Feeney, Erin; Clark, Courtney; Puwal, Steffan

    Heart disease is the leading cause of mortality in the United States. Rotary electrical waves within heart muscle underlie electrical disorders of the heart termed fibrillation; their propagation and breakup leads to a complex distribution of electrical activation of the tissue (and of the ensuing mechanical contraction that comes from electrical activation). Successful heart defibrillation has, thus far, been limited to delivering large electrical shocks to activate the entire heart and reset its electrical activity. In theory, defibrillation of a system this nonlinear should be possible with small electrical perturbations (stimulations). A successful algorithm for such a low-energy defibrillator continues to elude researchers. We propose to examine in silica whether low-energy electrical stimulations can be combined with antiarrhythmic, ion channel-blocking drugs to achieve a higher rate of defibrillation and whether the antiarrhythmic drugs should be delivered before or after electrical stimulation has commenced. Progress toward a more successful, low-energy defibrillator will greatly minimize the adverse effects noted in defibrillation and will assist in the development of pediatric defibrillators.

  7. Nonlinear and stochastic dynamics in the heart

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Zhilin, E-mail: zqu@mednet.ucla.edu [Department of Medicine (Cardiology), David Geffen School of Medicine, University of California, Los Angeles, CA 90095 (United States); Hu, Gang [Department of Physics, Beijing Normal University, Beijing 100875 (China); Garfinkel, Alan [Department of Medicine (Cardiology), David Geffen School of Medicine, University of California, Los Angeles, CA 90095 (United States); Department of Integrative Biology and Physiology, University of California, Los Angeles, CA 90095 (United States); Weiss, James N. [Department of Medicine (Cardiology), David Geffen School of Medicine, University of California, Los Angeles, CA 90095 (United States); Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, CA 90095 (United States)

    2014-10-10

    In a normal human life span, the heart beats about 2–3 billion times. Under diseased conditions, a heart may lose its normal rhythm and degenerate suddenly into much faster and irregular rhythms, called arrhythmias, which may lead to sudden death. The transition from a normal rhythm to an arrhythmia is a transition from regular electrical wave conduction to irregular or turbulent wave conduction in the heart, and thus this medical problem is also a problem of physics and mathematics. In the last century, clinical, experimental, and theoretical studies have shown that dynamical theories play fundamental roles in understanding the mechanisms of the genesis of the normal heart rhythm as well as lethal arrhythmias. In this article, we summarize in detail the nonlinear and stochastic dynamics occurring in the heart and their links to normal cardiac functions and arrhythmias, providing a holistic view through integrating dynamics from the molecular (microscopic) scale, to the organelle (mesoscopic) scale, to the cellular, tissue, and organ (macroscopic) scales. We discuss what existing problems and challenges are waiting to be solved and how multi-scale mathematical modeling and nonlinear dynamics may be helpful for solving these problems.

  8. Cardiac fluid dynamics anticipates heart adaptation.

    Science.gov (United States)

    Pedrizzetti, Gianni; Martiniello, Alfonso R; Bianchi, Valter; D'Onofrio, Antonio; Caso, Pio; Tonti, Giovanni

    2015-01-21

    Hemodynamic forces represent an epigenetic factor during heart development and are supposed to influence the pathology of the grown heart. Cardiac blood motion is characterized by a vortical dynamics, and it is common belief that the cardiac vortex has a role in disease progressions or regression. Here we provide a preliminary demonstration about the relevance of maladaptive intra-cardiac vortex dynamics in the geometrical adaptation of the dysfunctional heart. We employed an in vivo model of patients who present a stable normal heart function in virtue of the cardiac resynchronization therapy (CRT, bi-ventricular pace-maker) and who are expected to develop left ventricle remodeling if pace-maker was switched off. Intra-ventricular fluid dynamics is analyzed by echocardiography (Echo-PIV). Under normal conditions, the flow presents a longitudinal alignment of the intraventricular hemodynamic forces. When pacing is temporarily switched off, flow forces develop a misalignment hammering onto lateral walls, despite no other electro-mechanical change is noticed. Hemodynamic forces result to be the first event that evokes a physiological activity anticipating cardiac changes and could help in the prediction of longer term heart adaptations.

  9. Pathophysiology of valvular heart disease.

    Science.gov (United States)

    Zeng, Y I; Sun, Rongrong; Li, Xianchi; Liu, Min; Chen, Shuang; Zhang, Peiying

    2016-04-01

    Valvular heart disease (VHD) is caused by either damage or defect in one of the four heart valves, aortic, mitral, tricuspid or pulmonary. Defects in these valves can be congenital or acquired. Age, gender, tobacco use, hypercholesterolemia, hypertension, and type II diabetes contribute to the risk of disease. VHD is an escalating health issue with a prevalence of 2.5% in the United States alone. Considering the likely increase of the aging population worldwide, the incidence of acquired VHD is expected to increase. Technological advances are instrumental in identifying congenital heart defects in infants, thereby adding to the growing VHD population. Almost one-third of elderly individuals have echocardiographic or radiological evidence of calcific aortic valve (CAV) sclerosis, an early and subclinical form of CAV disease (CAVD). Of individuals ages >60, ~2% suffer from disease progression to its most severe form, calcific aortic stenosis. Surgical intervention is therefore required in these patients as no effective pharmacotherapies exist. Valvular calcium load and valve biomineralization are orchestrated by the concerted action of diverse cell-dependent mechanisms. Signaling pathways important in skeletal morphogenesis are also involved in the regulation of cardiac valve morphogenesis, CAVD and the pathobiology of cardiovascular calcification. CAVD usually occurs without any obvious symptoms in early stages over a long period of time and symptoms are identified at advanced stages of the disease, leading to a high rate of mortality. Aortic valve replacement is the only primary treatment of choice. Biomarkers such as asymmetric dimethylarginine, fetuin-A, calcium phosphate product, natriuretic peptides and osteopontin have been useful in improving outcomes among various disease states. This review, highlights the current understanding of the biology of VHD, with particular reference to molecular and cellular aspects of its regulation. Current clinical questions

  10. Heart-on-a-chip based on stem cell biology.

    Science.gov (United States)

    Jastrzebska, Elzbieta; Tomecka, Ewelina; Jesion, Iwona

    2016-01-15

    Heart diseases are one of the main causes of death around the world. The great challenge for scientists is to develop new therapeutic methods for these types of ailments. Stem cells (SCs) therapy could be one of a promising technique used for renewal of cardiac cells and treatment of heart diseases. Conventional in vitro techniques utilized for investigation of heart regeneration do not mimic natural cardiac physiology. Lab-on-a-chip systems may be the solution which could allow the creation of a heart muscle model, enabling the growth of cardiac cells in conditions similar to in vivo conditions. Microsystems can be also used for differentiation of stem cells into heart cells, successfully. It will help better understand of proliferation and regeneration ability of these cells. In this review, we present Heart-on-a-chip systems based on cardiac cell culture and stem cell biology. This review begins with the description of the physiological environment and the functions of the heart. Next, we shortly described conventional techniques of stem cells differentiation into the cardiac cells. This review is mostly focused on describing Lab-on-a-chip systems for cardiac tissue engineering. Therefore, in the next part of this article, the microsystems for both cardiac cell culture and SCs differentiation into cardiac cells are described. The section about SCs differentiation into the heart cells is divided in sections describing biochemical, physical and mechanical stimulations. Finally, we outline present challenges and future research concerning Heart-on-a-chip based on stem cell biology.

  11. Animal models of heart failure recent developments and perspectives.

    Science.gov (United States)

    Hongo, M; Ryoke, T; Ross, J

    1997-07-01

    Heart failure is a complex syndrome characterized by inability of the heart to supply sufficient cardiac output to meet the metabolic needs of the body. Over the past few decades, a number of animal models of heart failure have been developed to study questions that cannot be readily studied in the clinical setting. Because the syndrome of heart failure in humans has many underlying causes, ranging from primary myocardial disease (often of unknown etiology) to myocardial failure consequent to ventricular overload with secondary cardiac hypertrophy (as in hypertension, valvular heart disease, or myocardial infarction), no single animal model can successfully mimic the pathophysiology of these clinical settings. Regardless of the original cardiac abnormality, however, the end-stage heart failure syndrome generally presents a picture of cardiac dilation and circulatory congestion associated with maladaptive neurohumoral responses affecting the heart and peripheral circulation, which provide prime targets for new treatment strategies. An ideal animal model of heart failure should mimic the clinical setting as closely as possible, be accessible and reproducible, relatively stable under chronic conditions, and sufficiently economical to permit experiments in a large number of animals. In this review, we discuss the advantages and disadvantages of naturally occurring models of heart failure and models in which heart failure is induced in normal animals, focusing in particular on models that are useful for exploring disease mechanisms and interventions to prevent or treat heart failure. Much is being learned from large animals such as the dog and pig, although small animal models (rat and hamster) have many favorable features, and as genetic methods and miniaturized physiologic techniques mature, the mouse is beginning to provide gene-based models of cardiac failure aimed at better understanding of molecular mechanisms. (Trends Cardiovasc Med 1997;7:161-167). © 1997

  12. Heart transplantation in adults with congenital heart disease.

    Science.gov (United States)

    Houyel, Lucile; To-Dumortier, Ngoc-Tram; Lepers, Yannick; Petit, Jérôme; Roussin, Régine; Ly, Mohamed; Lebret, Emmanuel; Fadel, Elie; Hörer, Jürgen; Hascoët, Sébastien

    2017-02-22

    With the advances in congenital cardiac surgery and postoperative care, an increasing number of children with complex congenital heart disease now reach adulthood. There are already more adults than children living with a congenital heart defect, including patients with complex congenital heart defects. Among these adults with congenital heart disease, a significant number will develop ventricular dysfunction over time. Heart failure accounts for 26-42% of deaths in adults with congenital heart defects. Heart transplantation, or heart-lung transplantation in Eisenmenger syndrome, then becomes the ultimate therapeutic possibility for these patients. This population is deemed to be at high risk of mortality after heart transplantation, although their long-term survival is similar to that of patients transplanted for other reasons. Indeed, heart transplantation in adults with congenital heart disease is often challenging, because of several potential problems: complex cardiac and vascular anatomy, multiple previous palliative and corrective surgeries, and effects on other organs (kidney, liver, lungs) of long-standing cardiac dysfunction or cyanosis, with frequent elevation of pulmonary vascular resistance. In this review, we focus on the specific problems relating to heart and heart-lung transplantation in this population, revisit the indications/contraindications, and update the long-term outcomes.

  13. "Young at heart": Regenerative potential linked to immature cardiac phenotypes.

    Science.gov (United States)

    Gomes, Renata S M; Skroblin, Philipp; Munster, Alex B; Tomlins, Hannah; Langley, Sarah R; Zampetaki, Anna; Yin, Xiaoke; Wardle, Fiona C; Mayr, Manuel

    2016-03-01

    The adult human myocardium is incapable of regeneration; yet, the zebrafish (Danio rerio) can regenerate damaged myocardium. Similar to the zebrafish heart, hearts of neonatal, but not adult mice are capable of myocardial regeneration. We performed a proteomics analysis of adult zebrafish hearts and compared their protein expression profile to hearts from neonatal and adult mice. Using difference in-gel electrophoresis (DIGE), there was little overlap between the proteome from adult mouse (>8weeks old) and adult zebrafish (18months old) hearts. Similarly, there was a significant degree of mismatch between the protein expression in neonatal and adult mouse hearts. Enrichment analysis of the selected proteins revealed over-expression of DNA synthesis-related proteins in the cardiac proteome of the adult zebrafish heart similar to neonatal and 4days old mice, whereas in hearts of adult mice there was a mitochondria-related predominance in protein expression. Importantly, we noted pronounced differences in the myofilament composition: the adult zebrafish heart lacks many of the myofilament proteins of differentiated adult cardiomyocytes such as the ventricular isoforms of myosin light chains and nebulette. Instead, troponin I and myozenin 1 were expressed as skeletal isoforms rather than cardiac isoforms. The relative immaturity of the adult zebrafish heart was further supported by cardiac microRNA data. Our assessment of zebrafish and mammalian hearts challenges the assertions on the translational potential of cardiac regeneration in the zebrafish model. The immature myofilament composition of the fish heart may explain why adult mouse and human cardiomyocytes lack this endogenous repair mechanism.

  14. Arrhythmogenic remodelling of activation and repolarization in the failing human heart.

    Science.gov (United States)

    Holzem, Katherine M; Efimov, Igor R

    2012-11-01

    Heart failure is a major cause of disability and death worldwide, and approximately half of heart failure-related deaths are sudden and presumably due to ventricular arrhythmias. Patients with heart failure have been shown to be at 6- to 9-fold increased risk of sudden cardiac death compared to the general population. (AHA. Heart Disease and Stroke Statistics-2003 Update. Heart and Stroke Facts. Dallas, TX: American Heart Association; 2002) Thus, electrophysiological remodelling associated with heart failure is a leading cause of disease mortality and has been a major investigational focus examined using many animal models of heart failure. While these studies have provided an important foundation for understanding the arrhythmogenic pathophysiology of heart failure, the need for corroborating studies conducted on human heart tissue has been increasingly recognized. Many human heart studies of conduction and repolarization remodelling have now been published and shed some light on important, potentially arrhythmogenic, changes in human heart failure. These studies are being conducted at multiple experimental scales from isolated cells to whole-tissue preparations and have provided insight into regulatory mechanisms such as decreased protein expression, alternative mRNA splicing of ion channel genes, and defective cellular trafficking. Further investigations of heart failure in the human myocardium will be essential for determining possible therapeutic targets to prevent arrhythmia in heart failure and for facilitating the translation of basic research findings to the clinical realm.

  15. Protect Your Heart in the Heat

    Science.gov (United States)

    ... Cholesterol Tools & Resources Congenital Defects Children & Adults About Congenital Heart Defects The Impact of Congenital Heart Defects Understand Your Risk for Congenital Heart Defects Symptoms & ...

  16. When a Heart Murmur Signals Valve Disease

    Science.gov (United States)

    ... Cholesterol Tools & Resources Congenital Defects Children & Adults About Congenital Heart Defects The Impact of Congenital Heart Defects Understand Your Risk for Congenital Heart Defects Symptoms & ...

  17. Race By Hearts

    DEFF Research Database (Denmark)

    Sonne, Tobias; Jensen, Mads Møller

    2014-01-01

    In this paper, we explore the qualities of sharing biometric data in re- al-time between athletes, in order to increase two motivational factors for gym- goers: Enjoyment and social interaction. We present a novel smartphone appli- cation, called Race By Hearts, which enables competition based...... on heart rate data sharing between users in real-time. Through an empirical study conducted in the gym, we show that sharing biometric data in real-time can strengthen so- cial relations between participants, increase motivation, and improve the en- joyment of the fitness activity. Nevertheless, we found...

  18. Towards defining heart failure in adults with congenital heart disease.

    Science.gov (United States)

    Bolger, Aidan P; Gatzoulis, Michael A

    2004-12-01

    Injury to the myocardium disrupts geometric integrity and results in changes to intracardiac pressure, wall stress and tension, and the pattern of blood flow through the heart. Significant disruption to pump function results in heart failure which is defined in terms of symptoms: breathlessness and fatigue, signs of salt and water retention, and neurohormonal activation. This syndrome most commonly occurs in the context of injury due to ischaemic heart disease and dilated cardiomyopathy but because patients with congenital heart disease (CHD) are born with sometimes gross distortions of cardiac anatomy they too are subject to the forces that drive heart failure. This paper explores the available data relating to the clinical and neurohormonal manifestations of heart failure in patients with congenital heart disease and describes how, by additionally exploring events at a cellular level, we may be able to arrive at a definition of heart failure relevant to this population.

  19. Heart Truth for Women: If You Have Heart Disease

    Science.gov (United States)

    ... of physical activity • Unhealthy diet • Diabetes and prediabetes • Metabolic syndrome Other conditions and factors also may contribute to ... The Heart Truth is a way of informing women about what they can do to prevent heart ...

  20. Heart failure association of the European society of cardiology specialist heart failure curriculum.

    Science.gov (United States)

    McDonagh, Theresa A; Gardner, Roy S; Lainscak, Mitja; Nielsen, Olav W; Parissis, John; Filippatos, Gerasimos; Anker, Stefan D

    2014-02-01

    It is well established that organized care of heart failure patients, including specialist management by cardiologists, improves patient outcomes. In response to this, other national training bodies (the UK and the USA) have developed heart failure subspecialty curricula within their Cardiology Training Curricula. In addition, European Society of Cardiology (ESC) subspecialty curricula exist for Interventional Cardiology and Heart Rhythm Management. The purpose of this heart failure curriculum is to provide a framework which can be used as a blueprint for training across Europe. This blueprint mirrors other ESC curricula. Each section has three components: the knowledge required, the skills which are necessary, and the professionalism (attitudes and behaviours) which should be attained. The programme is designed to last 2 years. The first year is devoted to the specialist heart failure module. The second year allows completion of the optional modules of advanced imaging, device therapy for implanters, cardiac transplantation, and mechanical circulatory support. The second year can also be devoted to continuation of specialist heart failure training and/or research for those not wishing to continue with the advanced modules.

  1. 基于数据挖掘和网络分析的“脑心同治”分子机制研究%Molecular mechanism research on simultaneous therapy of brain and heart based on data mining and network analysis

    Institute of Scientific and Technical Information of China (English)

    陈迪; 卢朋; 张方博; 唐仕欢; 杨洪军

    2013-01-01

    研究从分子层面出发,结合利用信息技术中的网络分析、聚类和关联规则分析方法,找到步长脑心通这一实现脑心同治的方剂中的化合物成分共同作用于人体内的主要靶标组合,并对比分析这些主要成分在基于冠心病和中风病相关的蛋白质交互作用网络中作用的节点的异同.结果从分子层面上找出该方的主要成分对于2种疾病频繁作用的共同靶标及对于2种疾病分别作用到的不同靶标,同时确定了主要成分在作用于2种疾病共同靶标的同时也间接影响到不同靶标,从而解释其脑心同治的分子作用机制.%Objective:The theory of treating heart and brain simultaneously is from the theory of traditional Chinese medicine,and there aren't enough explanations for this theory from the perspective of molecular mechanism.As one successful case of this theory,the Chinese medicine formula——Buchang Naoxintong can achieve the goal of treating coronary heart disease and stroke at the same time.To illustrate the mechanism of the theory of treating heart and brain simultaneously,it is necessary to find out the molecular mechanism of this formula.Method:Using the network analysis method,together with two data mining methods-clustering and apriori algorithm,the frequent gene combinations interfered by the chemicals of the formula based on the protein-protein interaction networks related with coronary heart disease and stroke disease were figured out respectively.To find out the molecular mechanism of the theory of treating heart and brain simultaneously,the results got from two diseases were compared and analyzed.Result:Based on comparing two results from these two different diseases,the mechanism of the theory of treating heart and brain simultaneously was explained from molecular level by finding out key genes targeted by the components of this formula for both diseases and some particular genes interfered by the components for each

  2. Heart Health: Learn the Truth About Your Heart

    Science.gov (United States)

    ... Bar Home Current Issue Past Issues Cover Story Heart Health Learn the Truth About Your Heart Past Issues / Winter 2009 Table of Contents For ... turn Javascript on. Photo: iStock February is American Heart Month. Now is the time to make sure ...

  3. 缺血前预处理对心脏缺血后再灌注损伤的影响及其机制%Effects of ischemic preconditioning with atorvastatin on heart ischemia-reperfusion injury and possible mechanism

    Institute of Scientific and Technical Information of China (English)

    任凌云; 刘志刚; 黄晓帆

    2014-01-01

    目的 探讨缺血前预处理对心脏缺血后再灌注损伤的影响与机制.方法 健康清洁级雄性SD大鼠66只,均建立缺血再灌注(I/R)型,然后分为3个实验组,每组22只大鼠,具体为(1)对照(control)组:心脏持续缓冲液灌注;(2) I/R组:心脏接受30 min全心缺血后行120 min再灌注;(3)阿托伐他汀处理(Ator)组:全心缺血前给予Ator 1 μmol/L灌流30 min后行I/R处理.观察与测定3组的心肌超微结构、心梗面积、血流动力学、血清乳酸脱氢酶含量、三磷酸腺苷(ATP)与烟酰胺腺嘌呤二核苷酸(NAD+)水平.结果 I/R组与Ator组结扎前降支后心电图ST段弓背向上抬高,与T波融合;control组手术前后心电图无明显变化;与I/R组比较,Ator组的心肌梗死面积显著减少(P<0.05).显微结构显示3组中心肌细胞水肿、肌原纤维排列、线粒体结构与糖原颗粒都有明显不同.L/R后,I/R组与Ator组左室收缩压(LVSP)、左室压力下降的峰速度(dp/dtmin)和心率(HR)值明显降低,而左室舒张末期压(LVEDP)明显升高(P<0.05);Ator组中上述值LVSP与dp/dtmin值明显高于I/R组,而LVEDP与HR值明显低于I/R组(P<0.05).control组的乳酸脱氢酶(LDH)水平为(164.32±20.84) U/L,I/R组为(3589.63±133.25) U/L,Ator组为(1703.25±155.80) U/L,I/R组较control组LDH水平显著增加(P<0.05);而与I/R组比较,Ator组的LDH活性显著下降(P<0.05).与control组比较,I/R组内心肌ATP与NAD+含量明显降低(P<0.05);Ator组较I/R组心肌内ATP与NAD+含量显著升高(P<0.05).结论 阿托伐他汀预处理,在I/R损伤中能有效发挥保护心肌作用,其机制是通过线粒体ATP敏感性钾通道活化与降低心肌中LDH释放介导的.%Objective To investigate the effects of pretreatment with atorvastatin (Ator) on the heart ischemia-reperfusion injury (IRI) and the possible mechanism.Methods After establishment of IRI models,66 healthy male SD rats were divided into three experimental groups (n =22

  4. Diabetes, Heart Disease, and Stroke

    Science.gov (United States)

    ... Disease, & Other Dental Problems Diabetes & Sexual & Urologic Problems Diabetes, Heart Disease, and Stroke Having diabetes means that ... help to stop. What is the link between diabetes, heart disease, and stroke? Over time, high blood ...

  5. How Is Heart Failure Diagnosed?

    Science.gov (United States)

    ... your heart pumps blood when it beats. Doppler Ultrasound A Doppler ultrasound uses sound waves to measure ... when your heart is working hard and beating fast. During stress testing , you exercise to make your ...

  6. Mental Health and Heart Health

    Science.gov (United States)

    ... Recognition & Awards Healthy Workplace Food and Beverage Toolkit Mental Health and Heart Health Updated:Nov 10,2015 For years, doctors thought the connection between mental health and heart health was strictly behavioral – such as ...

  7. Heart failure - fluids and diuretics

    Science.gov (United States)

    ... Mann DL, Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine . 10th ... Mann DL, Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of ...

  8. Hispanics and Heart Disease, Stroke

    Science.gov (United States)

    ... Thromboembolism Aortic Aneurysm More Hispanics and Heart Disease, Stroke Updated:Aug 30,2016 Heart disease is the No. 1 killer for all Americans and stroke is the fifth leading cause of death. Hispanics ...

  9. What Is a Heart Murmur?

    Science.gov (United States)

    ... Holes in the Heart How the Heart Works Patent Ductus Arteriosus Stress Testing Tetralogy of Fallot Rate This Content: Updated: December 9, 2016 Twitter Facebook YouTube Google+ SITE INDEX ACCESSIBILITY PRIVACY STATEMENT FOIA OIG CONTACT ...

  10. Heart Disease: Symptoms, Diagnosis, Treatment

    Science.gov (United States)

    ... Past Issues Cover Story Heart Health Heart Disease: Symptoms, Diagnosis, Treatment Past Issues / Winter 2009 Table of Contents ... to view a larger version of the image Symptoms It is very important to learn the signs ...

  11. Hypertensive Heart Disease

    DEFF Research Database (Denmark)

    Wachtell, Kristian

    2011-01-01

    Abstract Hypertensive heart disease is prevalent and during the last decade it has been determined that patients with left ventricular (LV) hypertrophy have increased cardiovascular morbidity and mortality. However, many have doubted the effectiveness of LV mass assessment because it is difficult...

  12. Feedback on heart attack.

    Science.gov (United States)

    Pearce, Lynne

    2016-04-13

    The Royal Brompton & Harefield NHS Foundation Trust in London is the largest heart and lung centre in the UK. This article explores a project carried out by nurses at the trust looking at the experiences of having an acute myocardial infarction, and how patients felt about taking part in a research study.

  13. [Echinococcosis of the heart].

    Science.gov (United States)

    Rein, R; Niggemann, B; Runge, M

    1996-06-01

    Human disease caused by echinococcus granulosus is rare in Northern Europe, but is seen increasingly due to migration of labour and of tourism to endemic areas e. g. Southern Europe and the Middle East. Echinococcosis of the heart occurs in only 0.5 to 2% of cases of echinococcosis. Diagnosis is difficult because of the long latency between infection and manifestation of disease, and also because symptoms are unspecific. It is a diagnosis "to think of". Apart from a thorough history serological tests and medical imaging (ultrasound, X-rays, computed tomography) are used in the diagnosis of echinococcosis. Surgery is the preferred therapy, if not feasible medical treatment with benzimidazoles (Albendazole and Mebendazole) is effective. We describe a case of echinococcosis of the heart as the only manifestation of the disease: a 34-year-old male Turkish patient came in severe cardiac shock due to cardiac tamponade to the emergency department. Immediate heart surgery revealed a pericardium filled with cysts of echinococcus granulosus, infiltrating the left ventricle of the heart (Figure 1). The cysts were removed and the patient was put on a 2-year course of Mebendazole. The patient is free of relapse for more than 6 years now and he is considered to be cured.

  14. Heart Disease and Stroke

    Centers for Disease Control (CDC) Podcasts

    2013-09-03

    In this podcast, Dr. Tom Frieden, CDC Director, discusses the number one killer in the United States - heart disease and stroke.  Created: 9/3/2013 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 3/6/2014.

  15. Copeptin in Heart Failure

    DEFF Research Database (Denmark)

    Balling, Louise; Gustafsson, Finn

    2016-01-01

    Heart failure (HF) is one of the most common causes of hospitalization and mortality in the modern Western world and an increasing proportion of the population will be affected by HF in the future. Although HF management has improved quality of life and prognosis, mortality remains very high...

  16. The Danish Heart Register

    DEFF Research Database (Denmark)

    Abildstrom, S. Z.; Madsen, Mette

    2011-01-01

    Introduction: The Danish Heart Register (DHR) is a clinical database of invasive procedures within cardiology. Content: All providers of these procedures have been obliged to report to DHR since 2000. DHR is used to monitor the activity and quality of the procedures and serves as a data source...

  17. Congenital heart disease

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    970296 Evaluating the degree of pulmonary vascularlesions in congenital heart disease with selective pul-monary angiography. PAN Shiwei(潘世伟), et al.Fuwai Hosp, CAMS & PUMC, Beijing, 100037. Chin JCardiol 1997; 25(1): 39-41. Objective: To evaluate the degree of pulmonary vas-

  18. Heart disease - risk factors

    Science.gov (United States)

    ... classes or programs, or things like meditation or yoga. Limiting how much alcohol you drink to 1 drink a day for women and 2 a day for men. Good nutrition is important to your heart health and will help control some of your risk ...

  19. Congenital Heart Information Network

    Science.gov (United States)

    ... and Uwe Baemayr for The Congenital Heart Information Network Exempt organization under Section 501(c)3. Copyright ©1996 - 2016 C.H.I.N. All rights reserved TX4-390-685 Original site design and HTML by Panoptic Communications

  20. Sweet & Simple Clay Hearts

    Science.gov (United States)

    White, Heather

    2010-01-01

    Nothing pleases parents more than receiving handmade gifts from their children, especially if the gift is in the shape of a heart. Nothing pleases an art teacher more than having a lesson that is easy to follow, teaches basic skills, and enables students to be successful with the activity. In this article, the author describes how to create a…