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Mitral
Terms modified by Mitral Selected AbstractsAge- and Sex-Related Differences in the Tissue Doppler Imaging Parameters of Left Ventricular Diastolic DysfunctionECHOCARDIOGRAPHY, Issue 6 2007Hyeun S. Park M.D. Background: The effect of age and gender on tissue Doppler imaging measurements comparing the septal and mitral annulus needs to be investigated. Methods: We investigated in 276 outpatients in a university cardiology practice the relationship of age and gender to left atrial (LA) size, LA volume, mitral pulse-wave Doppler E/A ratio, E/Ea ratios by tissue Doppler image of mitral annular velocity (TDI), and left ventricular diastolic dysfunction (LVDD) by TDI. Results: Mitral E/A inflow was statistically decreased with age. E/Ea ratios of the lateral and mean of both lateral and septal annulus showed a statistical increase with age, while the E/Ea ratio of the septal annulus did not correlate with age. When comparing men and women of all ages, the mean LA volume for men was 59.2 cm3± 24.36 cm3 versus 48.54 cm3± 16.14 cm3 (P-value < 0.0001) and the mean LA size was 4.0 + 0.51 cm for men and 3.65 + 0.47 for women (P-value < 0.0001). There was no statistical difference between men and women when looking at mitral E/A inflow ratio, deceleration time, E/Ea ratio of the septal annulus, E/Ea ratio of the lateral annulus, E/Ea ratio of the mean of both septal and lateral annulus, and grades of LVDD. Conclusion: In patients 70 years of age or older, the mean diastolic grade was mild-to-moderate LVDD when using lateral or mean of septal and lateral annular measurements. When only the septal annular measurements were used to determine diastolic grade, all four age groups showed a mean of mildly to moderately impaired LVDD and showed no correlation with age. There were no differences in tissue Doppler imaging measurements between men and women. [source] Improvement in "uremic" cardiomyopathy by persistent ultrafiltrationHEMODIALYSIS INTERNATIONAL, Issue 1 2007Hüseyin TÖZ Abstract Some patients with end-stage renal disease suffer severe cardiac dilatation with functional disturbances, notably low ejection fraction (EF) and valvular regurgitation. They often have normal or low blood pressure, and tolerate ultrafiltration (UF) poorly. The aim of our study was to investigate to what extent this condition can still be improved by persistent slow UF. Twelve patients with cardiothoracic index >0.54 and EF <0.45 but otherwise uncomplicated were treated by slow, prolonged UF during hemodialysis (3 times a week) sessions, if necessary supplemented by isolated UF sessions on a separate day. Repeated chest X-rays and Doppler echocardiography were applied. During treatment periods varying from 20 to 120 days, all of the patients lost weight (12±10 kg) and became edema free. Cardiothoracic index decreased in all patients from a mean of 0.59±0.04 to 0.47±0.03. Blood pressure decreased when it had been elevated and increased when it was below normal. Ejection fraction increased in all of them from a mean of 0.31±0.9 to 0.50±0.9. Mitral and tricuspid regurgitation were found in every patient and disappeared or improved in all of them. Striking improvement of cardiac dilatation and dysfunction can be achieved by carefully monitored persistent UF in the majority of patients with seemingly intractable dilated cardiomyopathy. [source] An Assessment of the Terminology Used by Diplomates and Students to Describe the Character of Equine Mitral and Aortic Valve Regurgitant Murmurs: Correlations with the Physical Properties of the SoundsJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 3 2003Jonathan M. Naylor Twenty students and 16 diplomates listened to 7 recordings made from 7 horses with either aortic (n = 3) or mitral valve (n = 4) regurgitant murmurs. A total of 30 different terms were used to describe the character of these murmurs. However, only 4 terms were used in a repeatable and consistent manner. Most people described the character of a given mitral or aortic valve murmur with 1 or 2 terms. Diplomates drew from a pool of terms that was about half the size of that used by students,.1 ±2.0 terms for diplomats (mean ±1 SD) versus 13.1 ±1.8 terms for students (P < .001). Only blowing, honking, buzzing, and musical were markedly associated with the recording played. Frequency analysis of the murmurs allowed them to be classified as containing harmonics (n = 4) or not containing harmonics (n = 3). Blowing was used to describe murmurs without harmonics on 39 of 48 occasions and corresponds to the term noisy used in some older descriptions of equine murmurs. Honking, musical, and buzzing were markedly associated with murmurs that contained harmonics; these terms were used 23, 13, and 12 of a possible 64 times, respectively. The frequency of buzzing and honking murmurs (72.7 ±9.3 and 88.4 ±46.3 Hz, respectively) was markedly lower than that of musical murmurs (156.8 ±81.1 Hz) (all P values <.01). Honking murmurs (0.392 ±0.092 seconds) were shorter than those described as buzzing or musical (0.496 ±0.205 and 0.504 ±0.116 seconds, respectively). The data suggest that the terminology for the character of aortic and mitral regurgitant murmurs should be restricted to 4 terms: blowing, honking, buzzing, and musical. Honking, buzzing, and musical describe murmurs with a peak dominant frequency and harmonics; blowing describes murmurs without a peak frequency. Effective communication could be enhanced by playing examples of reference sounds when these terms are taught so that nomenclature is used more uniformly. Key words: Cardiac; Heart; Learning; Meaning. [source] Serum Uric Acid Levels Correlate With Left Atrial Function and Systolic Right Ventricular Function in Patients With Newly Diagnosed Heart Failure: The Hellenic Heart Failure StudyCONGESTIVE HEART FAILURE, Issue 5 2008Christina Chrysohoou MD The authors sought to investigate whether serum uric acid levels are associated with systolic left and right ventricular function, as well as left atrial function in patients with newly diagnosed heart failure. The authors enrolled 106 consecutive patients (mean age 65±13 years). Echocardiographic and biochemical assessment was performed during the third day of hospitalization. Pulsed tissue Doppler imaging of the systolic function of mitral and tricuspid annulus was characterized by the systolic waves (Smv and Stv, respectively), expressed in cm/s, and the left atrial function by the Amv wave. Left atrial kinetics was calculated using an equation. Serum uric acid levels were inversely correlated with Stv (P=.005) and left atrial kinetics (P=.05), after controlling for potential confounders. Uric acid levels appear to be correlated with more impaired right ventricular systolic function and decreased left atrial work in patients with heart failure. [source] Olfactory sensory axon growth and branching is influenced by sonic hedgehogDEVELOPMENTAL DYNAMICS, Issue 7 2009Qizhi Gong Abstract Olfactory sensory neuron (OSN) axons extend from the olfactory epithelium to the olfactory bulb without branching until they reach their target region, the glomerulus. In this report, we present evidence to support the involvement of sonic hedgehog in promoting rat olfactory sensory axons to branch and to enter into the glomerulus. Sonic hedgehog (Shh) protein is detected in the glomeruli of the olfactory bulb, whereas its transcript is expressed in the mitral and tufted cells, suggesting that Shh in the glomeruli is produced by mitral and tufted cells. In primary OSN cultures, Shh-N peptide promotes olfactory axon branching. When Shh function is neutralized in vivo by its antibody, growth of newly generated OSN axons into the glomeruli is vastly reduced. Developmental Dynamics 238:1768,1776, 2009. © 2009 Wiley-Liss, Inc. [source] Olfactory epithelium influences the orientation of mitral cell dendrites during developmentDEVELOPMENTAL DYNAMICS, Issue 2 2005Laura López-Mascaraque Abstract We have established previously that, although the olfactory epithelium is absent in the homozygous Pax-6 mutant mouse, an olfactory bulb-like structure (OBLS) does develop. Moreover, this OBLS contains cells that correspond to mitral cells, the primary projection neurons in the olfactory bulb. The current study aimed to address whether the dendrites of mitral cells in the olfactory bulb or in the OBLS mitral-like cells, exhibit a change in orientation in the presence of the olfactory epithelium. The underlying hypothesis is that the olfactory epithelium imparts a trophic signal on mitral and mitral-like cell that influences the growth of their primary dendrites, orientating them toward the surface of the olfactory bulb. Hence, we cultured hemibrains from wild-type and Pax 6 mutant mice from two different embryonic stages (embryonic days 14 and 15) either alone or in coculture with normal olfactory epithelial explants or control tissue (cerebellum). Our results indicate that the final dendritic orientation of mitral and mitral-like cells is directly influenced both by age and indeed by the presence of the olfactory epithelium. Developmental Dynamics 232:325,335, 2005. © 2004 Wiley-Liss, Inc. [source] Development and topography of the lateral olfactory tract in the mouse: Imaging by genetically encoded and injected fluorescent markersDEVELOPMENTAL NEUROBIOLOGY, Issue 8 2006Andreas Walz Abstract In mammals, conventional odorants are detected by OSNs located in the main olfactory epithelium of the nose. These neurons project their axons to glomeruli, which are specialized structures of neuropil in the olfactory bulb. Within glomeruli, axons synapse onto dendrites of projection neurons, the mitral and tufted (M/T) cells. Genetic approaches to visualize axons of OSNs expressing a given odorant receptor have proven very useful in elucidating the organization of these projections to the olfactory bulb. Much less is known about the development and connectivity of the lateral olfactory tract (LOT), which is formed by axons of M/T cells connecting the olfactory bulb to central neural regions. Here, we have extended our genetic approach to mark M/T cells of the main olfactory bulb and their axons in the mouse, by targeted insertion of IRES-tauGFP in the neurotensin locus. In NT-GFP mice, we find that M/T cells of the main olfactory bulb mature and project axons as early as embryonic day 11.5. Final innervation of central areas is accomplished before the end of the second postnatal week. M/T cell axons that originate from small defined areas within the main olfactory bulb, as visualized by localized injections of fluorescent tracers in wild-type mice at postnatal days 1 to 3, follow a dual trajectory: a branch of tightly packed axons along the dorsal aspect of the LOT, and a more diffuse branch along the ventral aspect. The dorsal, but not the ventral, subdivision of the LOT exhibits a topographical segregation of axons coming from the dorsal versus ventral main olfactory bulb. The NT-GFP mouse strain should prove useful in further studies of development and topography of the LOT, from E11.5 until 2 weeks after birth. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006 [source] New Annular Tissue Doppler Markers of Pulmonary HypertensionECHOCARDIOGRAPHY, Issue 8 2010Angel López-Candales M.D., F.A.C.C., F.A.S.E. Background: Tissue Doppler imaging (TDI) of mitral (MA) and tricuspid annulus (TA) events characterizes systolic and diastolic properties of each respective ventricle. However, the effect of chronic pulmonary hypertension (cPH) on these TDI annular events has not been well described. Methods: Measurements of right ventricular (RV) performance with TDI of the lateral mitral and tricuspid annuli, to measure isovolumic contraction (IVC) and systolic (S) signals were recorded from 50 individuals without PH and from 50 patients with cPH. To avoid confounding variables, all patients had normal left ventricular ejection fraction and were in normal sinus rhythm at the time of the examination. Results: As expected, markers of RV systolic performance were markedly reduced while LV systolic function remained largely unaffected in cPH patients when compared to patients without PH. TDI interrogation of the MA revealed lengthening of the time interval between IVC and systolic signal (70 ± 17 msec) when compared to individuals without PH (43 ± 8 msec; P < 0.0001). In contrast, cPH markedly shortened the time interval between IVC and the TA systolic signal (34 ± 12 msec) when compared to individuals without PH (65 ± 17 msec; P < 0.0001). Conclusions: cPH lengthens time interval between the IVC and the MA systolic signal while shortening this same interval when the TA is interrogated with TDI; reflecting the potential influence that cPH exerts in biventricular performance. Whether measuring these intervals be routinely used in the follow-up of cPH patients will require further study. (Echocardiography 2010;27:969-976) [source] Evidence of Robust Coupling of Atrioventricular Mechanical Function of the Right Side of the Heart: Insights from M-Mode Analysis of Annular MotionECHOCARDIOGRAPHY, Issue 6 2008Raveen Bazaz M.D. Background: Extensive data exist regarding annular descent and ventricular function. We have already demonstrated significant differences in amplitude and timing of events between maximal mitral (MAPSE) and tricuspid (TAPSE) annular plane systolic excursion as well as described quantitative temporal differences in annular ascent (AA) between the right and left sides of the heart. However, whether any relationship exists between annular ascent and descent components remains uninvestigated. Methods: Left ventricular ejection fraction (LVEF), right ventricular fractional area change (RVFAC), MAPSE, TAPSE, MV, and TV AA as well as pulsed tissue Doppler of the lateral MV and TV annuli were recorded from 53 patients. Results: In this population (age 55 ± 17 years) mean LVEF was 55 ± 19%, mean RVFAC was 47 ± 20%, mean MAPSE was 2.11 ± 0.72 cm, mean TAPSE was 1.48 ± 0.44 cm, mean MV AA was 0.52 ± 0.17 cm, TV AA was 0.96 ± 0.47, MV A-wave 0.10 ± 0.04 cm/s, and TV A-wave was 0.13 ± 0.05 cm/s. A more robust correlation was seen between TV AA and RVFAC than between MV AA and LVEF and also between TV AA and pulsed TDI TV A-wave velocity than between MV AA and pulsed TDI MV A-wave. Conclusion: Our data reveal that mechanical systolic functions of the atria and the ventricles are more closely coupled on the right than on the left side of the heart. Whether this is a result of anatomic linking or chamber geometry will require further study. [source] Correlation between NT-pro BNP Levels and Early Mitral Annulus Velocity (E,) in Patients with Non,ST-Segment Elevation Acute Coronary SyndromeECHOCARDIOGRAPHY, Issue 4 2008Marcia M. Barbosa M.D., Ph.D. Acute coronary syndromes in the absence of ST-segment elevation (NSTE-ACS) are a heterogeneous entity in which early risk stratification is essential. Diastolic dysfunction is precocious and associated with poor prognosis. BNP has been recognized as a biochemical marker of ventricular dysfunction and ischemia. Objective: To investigate if there is correlation of NT pro-BNP levels with diastolic dysfunction in patients with NSTE-ACS. Methods: Fifty-two patients with NSTE-ACS admitted to the coronary unit were included. NT-pro brain natriuretic hormone (BNP) levels and a Doppler echocardiogram were obtained in all and systolic and diastolic functions were analyzed. Their Doppler indexes were compared with those of 53 age- and sex-matched controls, without heart failure symptoms and with normal ejection fraction (EF) and normal NT-pro BNP levels. Results: Twenty-four patients (46%) with unstable angina and 28 patients (54%) with acute myocardial infarction (AMI) were included. Mean EF was 55.9 ± 10.7% and mean NT-pro BNP level was 835 ± 989 pg/ml. No mitral or pulmonary venous flow parameters of diastolic function correlated with NT-pro BNP levels. E,/A, correlated with NT-pro BNP level in univariate analysis but, in a multivariate analysis, only the EF and the E, showed negative correlation with the peptide level (r =,0.33, P = 0.024 and r =,0.29, P = 0.045, respectively). Thirteen patients presented with stage II diastolic dysfunction but the NT-pro BNP level in these patients did not differ from the level in stage I patients. Conclusion: NT-pro BNP levels are elevated in acute coronary syndromes, even in the absence of significant necrosis. Of all echocardiographic parameters investigated, only E, and the EF correlated with the levels of NT-pro BNP in this group of patients. [source] ORIGINAL INVESTIGATIONS: Tissue Harmonic Imaging in Echocardiography: Better Valve Imaging, But at What Cost?ECHOCARDIOGRAPHY, Issue 2 2008Karin Hawkins M.D. Background: Tissue harmonic imaging (THI) improves echocardiographic image quality and is widely utilized. Unfortunately it also makes structures appear artificially thickened. We sought to examine its impact on the imaging of left-sided heart valves. Methods: A large echocardiographic database was searched for full, standard transthoracic echocardiographic exams performed 12-month periods before (n = 3,786) and after (n = 3,914) transition to THI at a single institution. Patients with prosthetic valves were excluded. Results: The mean age of patients was 63 ± 17 years and 65% were men. No appreciable difference in demographics was observed between time periods. While inadequate visualization of the mitral valve was reduced by 30% using THI (P = 0.014), reports of leaflet thickening increased by 28% (P = 0.005). Similarly, inadequate aortic valve visualization was reduced by 53% with THI (P < 0.001), at the expense of more aortic sclerosis (+6%, P = 0.034). Among the 480 patients with echocardiograms using each modality (time interval between studies: 370 ± 143 days), THI did not appreciably improve visualization of the either valve. Although no significant increase in mitral thickness was seen with THI, aortic sclerosis was increased by at least one grade in 24.5% (P < 0.006). Conclusion: This study suggests that while THI enhances imaging of difficult to visualize valves, it may overestimate mitral and aortic valve thickness. This could lead to overdiagnosis and unnecessary follow-up studies. Cardiologists interpreting THI echocardiograms should become familiar with the modality's shortcomings. [source] Age- and Sex-Related Differences in the Tissue Doppler Imaging Parameters of Left Ventricular Diastolic DysfunctionECHOCARDIOGRAPHY, Issue 6 2007Hyeun S. Park M.D. Background: The effect of age and gender on tissue Doppler imaging measurements comparing the septal and mitral annulus needs to be investigated. Methods: We investigated in 276 outpatients in a university cardiology practice the relationship of age and gender to left atrial (LA) size, LA volume, mitral pulse-wave Doppler E/A ratio, E/Ea ratios by tissue Doppler image of mitral annular velocity (TDI), and left ventricular diastolic dysfunction (LVDD) by TDI. Results: Mitral E/A inflow was statistically decreased with age. E/Ea ratios of the lateral and mean of both lateral and septal annulus showed a statistical increase with age, while the E/Ea ratio of the septal annulus did not correlate with age. When comparing men and women of all ages, the mean LA volume for men was 59.2 cm3± 24.36 cm3 versus 48.54 cm3± 16.14 cm3 (P-value < 0.0001) and the mean LA size was 4.0 + 0.51 cm for men and 3.65 + 0.47 for women (P-value < 0.0001). There was no statistical difference between men and women when looking at mitral E/A inflow ratio, deceleration time, E/Ea ratio of the septal annulus, E/Ea ratio of the lateral annulus, E/Ea ratio of the mean of both septal and lateral annulus, and grades of LVDD. Conclusion: In patients 70 years of age or older, the mean diastolic grade was mild-to-moderate LVDD when using lateral or mean of septal and lateral annular measurements. When only the septal annular measurements were used to determine diastolic grade, all four age groups showed a mean of mildly to moderately impaired LVDD and showed no correlation with age. There were no differences in tissue Doppler imaging measurements between men and women. [source] Atrial Dissection-Like Appearance Caused by Ileus Due to Metastatic Renal Cell CarcinomaECHOCARDIOGRAPHY, Issue 7 2006Mehmet Dogan M.D. Atrial dissection is an uncommon entity, defined as a gap from the mitral or tricuspid annular area to the interatrial septum or atrial wall, creating a new chamber with or without communication into the true left or right atrium. We present the interesting images of an atrial dissection-like appearance in the right atrium, which was actually caused by an ileus due to metastatic renal cell carcinoma in a 82-year-old man. The causes of true atrial dissection were also briefly discussed. [source] Noninvasive Assessment of Influence of Resistant Respiration on Blood Flow Velocities Across the Cardiac Valves in Humans,A Quantification Study by EchocardiographyECHOCARDIOGRAPHY, Issue 5 2004Lijun Yuan M.D. The aim of our study is to quantitatively investigate influence of the intrathoracic pressure change on the four cardiac valves' velocities and further verify a new proposal of the mechanism of respiratory influence on hemodynamics. Methods: Thirty healthy volunteers with no cardiopulmonary diseases were included. The intrathoracic pressure changes were measured with self-designed device. The velocity across the four cardiac valves during spontaneous respiration and with the intrathoracic pressure change at ,4, ,8, and ,12 mmHg, respectively, were recorded simultaneously with the electrocardiogram and respiratory curve. The respiratory variation indices (RVIs) were calculated. The average RVIs of mitral, aortic, tricuspid, and pulmonary valves were 12.54%, 13.19%; 6.23%, 8.27%; 20.27%, 24.36%; and 6.45%, 7.69% with intrathoracic pressure change at ,8 mmHg and ,12 mmHg, respectively. All the above parameters have a significant difference from those during spontaneous respiration (P < 0.01 or P < 0.001). We concluded that it might be the respiratory intrathoracic pressure change that causes the change of the velocity across the valves. (ECHOCARDIOGRAPHY, Volume 21, July 2004) [source] Successful Repair of Aortic and Mitral Incompetence Induced by Methylsergide Maleate: Confirmation by Intraoperative Transesophageal EchocardiographyECHOCARDIOGRAPHY, Issue 3 2003D.O., Thomas Joseph Methylsergide maleate, an effective anti-migraine medication, has a well-documented association with left-sided cardiac valve dysfunction. Prior reports have described cardiac valve dysfunction in patients using methylsergide chronically for a minimum of 6 years, with surgical intervention consisting of valve replacement for patients with intractable congestive heart failure. We report a 51-year-old woman who developed severe mitral and aortic valvular dysfunction after taking methylsergide maleate for migraine headaches for a period of 19 months, and who subsequently underwent aortic and mitral valve repair with excellent short-term results. (ECHOCARDIOGRAPHY, Volume 20, April 2003) [source] Is It Open or Is It Closed?ECHOCARDIOGRAPHY, Issue 4 2002Thrombosis of a St. Jude's Tricuspid Valve Prosthesis A 49-year-old woman with mitral and tricuspid mechanical valve prostheses developed marked weight gain with increasing abdominal girth and facial plethora 4 weeks after anticoagulation was temporarily interrupted for abdominal surgery. Transthoracic and transesophageal echocardiography documented severe tricuspid stenosis and regurgitation. The two discs of the tricuspid prosthesis were immobilized, half open and half closed. The prosthesis was replaced and the patient did well. [source] Effect of age and training on murmurs of atrioventricular valvular regurgitation in young ThoroughbredsEQUINE VETERINARY JOURNAL, Issue 3 2000L. E. Young Summary Cardiac auscultation was carried out on 111 Thoroughbred horses age 2,5 years to test the hypothesis that athletic training might influence the development of atrioventricular (AV) valve regurgitation in young Thoroughbreds. Murmurs of valvular regurgitation were identified and graded on a 1,6 scale. There were 2 sources of auscultation data: 1) 55 2-year-old horses that were examined by auscultation before training commenced and 9 months later when at race fitness; 2) 56 horses age 2,5 years that were examined on one occasion only (25 2-year-olds, 23 3-year-olds, five 4-year-olds and five 5-year olds). All horses in the second data set were in full training and racing regularly at the time of the examination. To conclude the study, 35 horses were selected randomly from both groups of horses and examined with colour-flow Doppler echocardiography. The aim of the final part of the study was to check specificity and sensitivity of auscultation for detection of AV valve murmurs and therefore validate the auscultation findings. Priorto training, the prevalence in 2-year-old racehorses of murmurs of mitral regurgitation and tricuspid regurgitation was 7.3% (4/55) and 12.7% (7/55), respectively. After training, the prevalence proportions increased to 21.8% (12/55) and 25.5% (14/55). After training, one horse developed a murmur characteristic of aortic regurgitation. The differences in murmur prevalence were statistically significant for mitral and tricuspid regurgitation (paired t test results: mitral regurgitation, P = 0.019; tricuspid regurgitation, P = 0.007), as were the differences in mean murmurgrade (P= 0.018 and P= 0.0006, respectively). There were no significant effects of age on the prevalence of valvular regurgitation in 56 horses examined at race fitness. Auscultation was a specific (specificity 100%) and reasonably sensitive method for detection of murmurs of mitral and tricuspid regurgitation (mitral regurgitation: positive predictive value 100%, negative predictive value 84%, tricuspid regurgitation: positive predictive value 100%, negative predictive value 65%). These data suggest that the prevalence and grade of murmurs of mitral and tricuspid valvular regurgitation increase in 2-year-old Thoroughbreds after 9 months of athletic training. Whereas the effects of age and growth on the prevalence of murmurs cannot be ruled out from these data, this study suggests that there is an influence of athletic training on the development of atrioventicular valvular regurgitation in flat-racing Thoroughbreds. [source] Expression of STAMP2 in monocytes associates with cardiovascular alterationsEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 6 2010Zhi-Hao Wang Eur J Clin Invest 2010; 40 (6): 490,496 Abstract Background, Metabolic and inflammatory pathways crosstalk at many levels. In this study, we aimed to investigate the expression of six-transmembrane protein of prostate 2 (STAMP2) in macrophages and tried to search for the association between the decreased STAMP2 expression, if any, and carotid atherosclerosis as well as cardiac adaptations. Materials and methods, A total of 97 unrelated Chinese subjects were recruited including 48 subjects with metabolic syndrome (MetS) and 49 controls. Clinical and biochemical characteristics were collected from subjects, with quantification of STAMP2 in monocyte/macrophages. All subjects underwent ultrasonography. Results, STAMP2 expression in macrophages was significantly decreased in MetS as compared with the control group (10·25 ± 9·20 vs. 15·20 ± 9·18, P = 0·009), especially in women patients. Partial correlation analysis showed that STAMP2 expression in macrophages correlated with BMI (r = ,0·375, P = 0·045), age (r = 0·414, P = 0·026) and HDL (r = 0·377, P = 0·044) after controlling for systolic blood pressure (SBP). Furthermore, STAMP2 expression was correlated with PI (r = ,0·454, P = 0·013), LVEF (r = ,0·503, P = 0·005), LA-ESR (r = ,0·424, P = 0·022), LA-S (r = 0·469, P = 0·010) and mitral E/A ratio (r = 0·492, P = 0·005) after controlling for SBP. Still, in multivariable analysis, STAMP2 expression was independently associated with IMTmean, PI and mitral E/A ratio. Conclusions, In MetS patients, especially women patients, STAMP2 expression was down-regulated in peripheral blood mononuclear cell, which was correlated with carotid atherosclerosis and cardiac adaptation. [source] Synapse-specific localization of vesicular glutamate transporters in the rat olfactory bulbEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 5 2007Marie-Madeleine Gabellec Abstract Vesicular glutamate transporters (VGLUTs) mediate the packaging of the excitatory neurotransmitter glutamate into synaptic vesicles. Three VGLUT subtypes have so far been identified, with distinct expression patterns in the adult brain. Here, we investigated the spatial distribution of the three VGLUTs in the rat olfactory bulb, a brain region containing a variety of glutamate synapses, both axodendritic and dendrodendritic. Using multilabelling confocal microscopy and electron microscopic immunocytochemistry, we showed that each VGLUT isoform has a highly selective localization in olfactory bulb synapses. VGLUT1 is present at dendrodendritic synapses established by the output neurones (mitral and tufted cells) with bulbar interneurones in the glomerular layer and external plexiform layer, as well as in axonal synapses of the granule cell layer. By contrast, VGLUT2 is strongly expressed in axon terminals of olfactory sensory neurones, which establish synapses with second-order neurones in the glomerular neuropil. VGLUT2 is also found in the outer part of the external plexiform layer and in the granule cell layer but colocalizes only partially with VGLUT1. Finally, we showed that VGLUT3 is exclusively located in the glomerular neuropil, where it colocalizes extensively with the vesicular inhibitory amino acid transporter vesicular GABA transporter, suggesting that it is associated with a subset of inhibitory synapses. Together, these observations extend previous findings on VGLUT distribution in the forebrain, and suggest that each VGLUT subtype has a specific function in the distinct features of axodendritic and dendrodendritic synapses that characterize the olfactory bulb circuit. [source] Pre- and postsynaptic GABAA receptors at reciprocal dendrodendritic synapses in the olfactory bulbEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2004Patrizia Panzanelli Abstract Presynaptic ionotropic receptors are important regulators of synaptic function; however, little is known about their organization in the presynaptic membrane. We show here a different spatial organization of presynaptic and postsynaptic GABAA receptors at reciprocal dendrodendritic synapses between mitral and granule cells in the rat olfactory bulb. Using postembedding electron microscopy, we have found that mitral cell dendrites express GABAA receptors at postsynaptic specializations of symmetric (GABAergic) synapses, as well as at presynaptic sites of asymmetric (glutamatergic) synapses. Analysis of the subsynaptic distribution of gold particles revealed that in symmetric synapses GABAA receptors are distributed along the entire postsynaptic membrane, whereas in asymmetric synapses they are concentrated at the edge of the presynaptic specialization. To assess the specificity of immunogold labelling, we analysed the olfactory bulbs of mutant mice lacking the ,1 subunit of GABAA receptors. We found that in wild-type mice ,1 subunit immunoreactivity was similar to that observed in rats, whereas in knockout mice the immunolabelling was abolished. These results indicate that in mitral cell dendrites GABAA receptors are distributed in a perisynaptic domain that surrounds the presynaptic specialization. Such presynaptic receptors may be activated by spillover of GABA from adjacent inhibitory synapses and modulate glutamate release, thereby providing a novel mechanism regulating dendrodendritic inhibition in the olfactory bulb. [source] ,And the beat goes on' The cardiac conduction system: the wiring system of the heartEXPERIMENTAL PHYSIOLOGY, Issue 10 2009Mark R. Boyett The cardiac conduction system (CCS), consisting of the sino-atrial node, atrioventricular node and His,Purkinje system, is responsible for the initiation and co-ordination of the heart beat. In the last decade, our understanding of the CCS has been transformed. Immunohistochemistry, used in conjunction with anatomical techniques, has transformed our understanding of its anatomy; arguably, we now understand the position of the sino-atrial node (not the same as in medical textbooks), and our new understanding of the atrioventricular node anatomy means that we can compute its physiological and pathophysiological behaviour. Ion channel expression in the CCS has been shown to be fundamentally different from that in the working myocardium. Dysfunction of the CCS has previously been attributed to fibrosis, but it is now clear that remodelling of ion channels plays an important role in dysfunction during ageing, heart failure and atrial fibrillation. Differences in ion channel expression may even be responsible for the bradycardia in the athlete and differences in heart rate among different species (such as humans and mice). Recent work has highlighted less well-known components of the CCS, including tricuspid, mitral and aortic rings and even a third (retro-aortic) node. These additional tissues do not participate in the initiation and co-ordination of the heart beat and instead they are likely to be the source of various life-threatening arrhythmias. During embryological development, all parts of the CCS have been shown to develop from the primary myocardium of the linear heart tube, partly under the influence of the transcription factor, Tbx3. [source] Transgenic expression of Cre recombinase in mitral/tufted cells of the olfactory bulbGENESIS: THE JOURNAL OF GENETICS AND DEVELOPMENT, Issue 1 2005Yumiko Nagai Abstract Olfactory information is conveyed from the periphery to the olfactory cortices through mitral and tufted (M/T) cells in the olfactory bulb. A mouse with a specific expression of Cre recombinase in M/T cells is essential for genetic marking of M/T cells and manipulating their properties. Protocadherin 21 (Pcdh21) expression is highly restricted to M/T cells. Here we report a transgenic mouse line, Pcdh21-Cre, in which ,10-kb mouse Pcdh21 promoter drives the expression of Cre recombinase. In Pcdh21-Cre mice, Cre recombinase activity is predominantly detected in M/T cells, visualized with the anti-CFP immunostaining in offspring of a cross between Pcdh21-Cre and the reporter Rosa26-loxP-stop-loxP-CFP strain. These results demonstrate that the ,10-kb Pcdh21 promoter can drive transcription in M/T cells and Pcdh21-Cre mice can be used to excise floxed DNA fragments in M/T cells, which provides a valuable tool to reveal the structure and function of the central olfactory circuits. genesis 43:12,16, 2005. © 2005 Wiley-Liss, Inc. [source] Evaluation of Left Ventricular Diastolic Function after Edge-to-Edge Mitral Valve PlastyJOURNAL OF CARDIAC SURGERY, Issue 1 2010Yong-Qiang Lai M.D. This procedure anchors the correspondence leaflets to create a double-orifice mitral valve. The original mitral valve anatomy is changed, and the opening of mitral valve is restricted. Little is known whether this procedure affects the left ventricular diastolic function. Methods: Thirty patients with mitral regurgitation were included in this study. Fifteen with posterior leaflet prolapse received quadrangular resection (group 1), 15 with anterior or bileaflet prolapse underwent edge-to-edge procedure (group 2). Acute hemodynamics was monitored with a Swan-Ganz catheter (Edwards Lifesciences LLC, Irvine, CA, USA). Left ventricular diastolic function was also evaluated with echocardiography in 28 patients with sinus rhythm. The ratio of peak E velocity and A velocity (E/A), the ratio of early diastolic peak flow velocity to early diastolic mitral annular movement velocity (E/Em), and the ratio of early diastolic mitral annular velocity to late diastolic mitral annular velocity (Em/Am) were measured before operation and one week after operation. Results: Mitral valve area and mitral regurgitate grade decreased significantly after operation. There was no significant change in pulmonary artery wedge pressure between two groups and in each group before and after operation. Echocardiography evaluation showed there was no significant difference in E/A, E/Em, and Em/Am before and after operation between two groups and in each group. Conclusion: Edge-to-edge mitral valve plasty procedure has no significant impairment on left ventricular diastolic function. A double-orifice mitral valve has similar hemodynamic behavior with a physiological valve.(J Card Surg 2010;25:5-8) [source] Beating-Heart Valvular Surgery: A Possible Alternative for Patients with Severely Compromised Ventricular FunctionJOURNAL OF CARDIAC SURGERY, Issue 2 2002Richard J. Kaplon M.D. We report a novel approach to myocardial protection in a patient requiring multi-valve surgery who had an ejection fraction of 15%. Warm oxygenated blood was infused continuously both antegrade and retrograde during aortic valve replacement and mitral and tricuspid valve repair. Adequacy of perfusion was confirmed by the absence of electrocardiographic changes. Clinical improvement suggests that this strategy of myocardial protection warrants further investigation. [source] Surface Electrocardiographic Patterns and Electrophysiologic Characteristics of Atrial Flutter Following Modified Radiofrequency MAZE ProceduresJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 4 2007JOSEPH G. AKAR M.D., Ph.D. Introduction: The radiofrequency MAZE is becoming a common adjunct to cardiac surgery in patients with atrial fibrillation. While a variety of postoperative arrhythmias have been described following the original Cox-MAZE III procedure, the electrophysiological characteristics and surgical substrate of post-radiofrequency MAZE flutter have not been correlated. We sought to determine the location, ECG patterns, and electrophysiological characteristics of post-radiofrequency MAZE atrial flutter. Methods: Nine consecutive patients with post-radiofrequency MAZE flutter presented for catheter ablation 9 ± 10 months after surgery. Results: Only one patient (11%) had an ECG appearance consistent with typical isthmus-dependent right atrial (RA) flutter. However, on electrophysiological study, 3/9 patients (33%) had typical right counter-clockwise flutter entrained from the cavo-tricuspid isthmus, despite description of surgical isthmus ablation. Six patients (67%) had left atrial (LA) circuits. These involved the mitral annulus in 5/6 cases (83%) despite description of surgical mitral isthmus ablation in the majority (60%). LA flutters had a shorter cycle length compared with RA flutters (253 ± 39 msec and 332 ± 63 msec respectively, P < 0.05). After a mean of 8 ± 4 months following ablation, 8/9 patients (89%) were in sinus rhythm. Conclusion: Up to one-third of post-radiofrequency MAZE circuits are typical isthmus-dependent RA flutters, despite a highly atypical surface ECG morphology. Therefore, diagnostic electrophysiological studies should commence with entrainment at the cavo-tricuspid isthmus in order to exclude typical flutter, regardless of the surface ECG appearance. Incomplete surgical lesions at the mitral and cavo-tricuspid isthmus likely predispose to the development of post-radiofrequency MAZE flutter. [source] Catheter Ablation of Long-Lasting Persistent Atrial Fibrillation: Critical Structures for TerminationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 11 2005MICHEL HAĎSSAGUERRE M.D. Background: The relative contributions of different atrial regions to the maintenance of persistent atrial fibrillation (AF) are not known. Methods: Sixty patients (53 ± 9 years) undergoing catheter ablation of persistent AF (17 ± 27 months) were studied. Ablation was performed in a randomized sequence at different left atrial (LA) regions and comprised isolation of the pulmonary veins (PV), isolation of other thoracic veins, and atrial tissue ablation targeting all regions with rapid or heterogeneous activation or guided by activation mapping. Finally, linear ablation at the roof and mitral isthmus was performed if sinus rhythm was not restored after addressing the above-mentioned areas. The impact of ablation was evaluated by the effect on the fibrillatory cycle length in the coronary sinus and appendages at each step. Activation mapping and entrainment maneuvers were used to define the mechanisms and locations of intermediate focal or macroreentrant atrial tachycardias. Results: AF terminated in 52 patients (87%), directly to sinus rhythm in 7 or via the ablation of 1,6 intermediate atrial tachycardias (total 87) in 45 patients. This conversion was preceded by prolongation of fibrillatory cycle length by 39 ± 9 msec, with the greatest magnitude occurring during ablation at the anterior LA, coronary sinus and PV-LA junction. Thirty-eight atrial tachycardias were focal (originating dominantly from these same sites), while 49 were macroreentrant (involving the mitral or cavotricuspid isthmus or LA roof). Patients without AF termination displayed shorter fibrillatory cycles at baseline: 130 ± 14 vs 156 ± 23 msec; P = 0.002. Conclusion: Termination of persistent AF can be achieved in 87% of patients by catheter ablation. Ablation of the structures annexed to the left atrium,the left atrial appendage, coronary sinus, and PVs,have the greatest impact on the prolongation of AF cycle length, the conversion of AF to atrial tachycardia, and the termination of focal atrial tachycardias. [source] Index of myocardial performance in patients with type 2 diabetes without hypertension and its relationship with clinical and echocardiographic parametersJOURNAL OF DIABETES, Issue 1 2009Hayrettin SAGLAM Abstract Background:, Diabetes mellitus affects the systolic and diastolic function of the left ventricle (LV). The aim of the present study was to evaluate the index of myocardial performance (IMP), a new Doppler index, in asymptomatic, normotensive patients with type 2 diabetes mellitus (T2DM). Methods:, The study population consisted of 40 asymptomatic normotensive patients with T2DM (22 women, 18 men; mean [±SD] age 49,±,7 years) and 20 healthy controls (13 women, seven men; mean age 45,±,4 years). M-Mode and two-dimensional Doppler echocardiography was performed in all subjects to calculate IMP. Venous blood samples were collected for analysis and body mass index (BMI) was calculated. Results:, In normotensive T2DM patients, the mitral E wave was decreased, whereas mitral A wave, mitral E/A ratio, and septal wall thickening were increased compared with values obtained for the control group. The IMP was higher in normotensive T2DM patients than in the control group (P = 0.004). There was a significant correlation between IMP and triglyceride (TG) levels (P,<,0.001), mitral E wave (P,<,0.001), mitral E/A ratio (P,<,0.001), ejection fraction (P = 0.001), fasting blood glucose (P =0.007), LV systolic dimension (P,<,0.001), duration of diabetes (P = 0.017), and BMI (P = 0.029). Stepwise multiple regression analysis demonstrated that only TG levels (, = 0.355, t = 2.487, P = 0.017) and the mitral E/A ratio (, = ,0.384, t = ,2.690, P = 0.011) had an independent effect on IMP. Conclusion:, The results of the present study indicate that IMP is increased in normotensive T2DM patients. The findings suggest that increased IMP may be an early sign of diabetic cardiomyopathy in normotensive diabetic patients with preserved LV function. [source] Advances in Heart Valve SurgeryJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 6 2003MATTHIAS AAZAMI Heart valve surgery continues to evolve in a dynamic fashion. While the exact role of minimally invasive approaches still needs to be defined, progress has been made in the development of new bioprostheses and their durability. Most importantly, valve repair has been standardized for the mitral and introduced for the aortic valve with results that have been superior to valve replacement. Selection of the optimal procedure for the individual patient is now facilitated. In the future, a wider application of repair procedures and further improvements of biologic valves can be anticipated not only to influence long-term results but also the decision-making process for conservative or surgical treatment. (J Interven Cardiol 2003;16:535,541) [source] Percutaneous Suture Closure for Management of Large French Size Arterial and Venous PunctureJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 4 2000TED FELDMAN M.D. Aortic valvuloplasty procedures have been limited principally by the occurrence of restenosis in this patient population. Once a decision has been made to proceed with aortic valvuloplasty, one of the next major concerns is management of the femoral artery puncture. For these procedures, 12Fr and 14Fr sheath introducers and prolonged compression with clamps or hemostatic devices have been necessary. Prolonged immobilization is painful for the elderly population in whom aortic valvuloplasty is used. The ability to use percutaneous suture closure to eliminate the need for manual compression, especially for clamp or hemostatic devices, has greatly improved patient tolerance for these procedures. A technique for preloading the suture closure device prior to insertion of a large bore sheath is the technique of choice to make this possible. Mitral valvuloplasty has faced fewer limitations and of course yields results equivalent to surgical commissurotomy in randomized trials. Improved management of the 14Fr femoral venous site has made outpatient treatment simpler. The technical approach necessary for success in the venous system uses contrast injections through the Perclose device marker port to insure that the device is properly positioned prior to deployment of the sutures. More rapid immobilization and simplified postprocedural management can be achieved using percutaneous suture closure for large caliber sheaths after mitral and aortic valvuloplasty. [source] Aortic and mitral regurgitation: Quantification using moving slice velocity mappingJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 2 2001Sebastian Kozerke PhD Abstract Comprehensive assessment of the severity of valvular insufficiency includes quantification of regurgitant volumes. Previous methods lack reliable slice positioning with respect to the valve and are prone to velocity offsets due to through-plane motion of the valvular plane of the heart. Recently, the moving slice velocity mapping technique was proposed. In this study, the technique was applied for quantification of mitral and aortic regurgitation. Time-efficient navigator-based respiratory artifact suppression was achieved by implementing a prospective k-space reordering scheme in conjunction with slice position correction. Twelve patients with aortic insufficiency and three patients with mitral insufficiency were studied. Aortic regurgitant volumes were calculated from diastolic velocities mapped with a moving slice 5 mm distal to the aortic valve annulus. Mitral regurgitant flow was indirectly assessed by measuring mitral inflow at the level of the mitral annulus and net aortic outflow. Regurgitant fractions, derived from velocity data corrected for through-plane motion, were compared to data without correction for through-plane motion. In patients with mild and moderate aortic regurgitation, regurgitant fractions differed by 60% and 15%, on average, when comparing corrected and uncorrected data, respectively. Differences in severe aortic regurgitation were less (7%). Due to the large orifice area of the mitral valve, differences were still substantial in moderate-to-severe mitral regurgitation (19%). The moving slice velocity mapping technique was successfully applied in patients with aortic and mitral regurgitation. The importance of correction for valvular through-plane motion is demonstrated. J. Magn. Reson. Imaging 2001;14:106,112. © 2001 Wiley-Liss, Inc. [source] | ||||||||||||||||||||||||||||