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Hemodynamic Data (hemodynamic + data)
Selected AbstractsEvaluation of Right Ventricular Fibrosis in Adult Congenital Heart Disease Using Gadolinium-enhanced Magnetic Resonance Imaging: Initial Experience in Patients with Right Ventricular Loading ConditionsCONGENITAL HEART DISEASE, Issue 5 2006Lopa P. Hartke MD ABSTRACT Objective., Gadolinium-enhanced cardiac magnetic resonance imaging has been used to show myocardial fibrosis, a finding that appears as late gadolinium enhancement. Its role in the evaluation of right ventricular fibrosis in congenital heart disease is unclear. The purpose of this study was to demonstrate late gadolinium enhancement of the right ventricle in adult and adolescent congenital heart disease and to investigate the relationship between this enhancement and clinical and pathophysiological data. Design., In total, 24 patients, 16 patients with congenital heart disease and right ventricular loading conditions and 8 controls, underwent gadolinium-enhanced viability imaging. Diagnoses varied and included repaired, palliated, and unrepaired lesions. The presence and extent of right ventricular late gadolinium enhancement was compared with patient clinical and hemodynamic data. Exact Wilcoxon tests, Fisher's exact tests, and Spearman's rank correlation were used to compare variables. Results., Nine of 16 patients (56%) were found to have right ventricular late gadolinium enhancement, ranging from 5% to 80% of right ventricular myocardium affected (mean 36.1%, SD 29.7). The combination of right ventricular systolic pressure ,98 mm Hg and systemic oxygen saturation ,93% strongly suggested the presence of right ventricular late gadolinium enhancement (positive predictive value 100%), but no single variable or combination of variables could reliably predict its absence (negative predictive values ,75%). Extent of right ventricular late gadolinium enhancement did not correlate with degree of either hypoxia or right ventricular hypertension. Conclusions., Gadolinium-enhanced cardiac magnetic resonance demonstrates right ventricular late gadolinium enhancement in some patients with congenital heart disease and right ventricular loading conditions. Clinical variables were associated with the presence of fibrosis but did not reliably predict severity. Myocardial preservation is likely a multifactorial process that may affect the right and left ventricles differently. [source] Evaluation of Left Ventricular Systolic and Diastolic Global Function: Peak Positive and Negative Myocardial Velocity Gradients in M-Mode Doppler Tissue ImagingECHOCARDIOGRAPHY, Issue 1 2002Yoshiki Ueno M.D. Objectives: To evaluate a new indicator of left ventricular global function: Myocardial velocity gradient (MVG) M-mode Doppler tissue imaging (DTI). Background: MVG is a new indicator of regional left ventricular function and global left ventricular diastolic function. However, it is unclear whether MVG also is an indicator of left ventricular global function in comparison with invasive indices. Methods: We performed conventional imaging and M-mode DTI in 85 subjects and calculated MVG at the posterior wall. We obtained satisfactory images in 65 subjects, who we divided into three groups: Noninvasive study group, invasive study group, and hemodialysis group. The noninvasive study group was divided into three subgroups (a younger normal subgroup, an older normal subgroup, and a cardiomyopathy subgroup), and MVG was compared with indices of conventional imaging. In the invasive study group, we compared MVG and indices of conventional imaging with hemodynamic data (peak positive and negative dp/dt, and the time constant T) using a high fidelity micromanometer-tipped catheter. In the hemodialysis group, we compared indices before hemodialysis with those after hemodialysis. Results: Peak positive MVG correlated well with peak positive dp/dt (r = 0.79), and this did not change with hemodialysis (P = 0.87). Peak negative MVG also correlated well with peak positive dp/dt and the time constant T (r = 0.88 and r = 0.80), and this did not change with hemodialysis (P = 0.97). Conclusions: Peak positive and negative MVG are sensitive and load-insensitive indicators of left ventricular function. [source] Bench to Bedside: Electrophysiologic and Clinical Principles of Noninvasive Hemodynamic Monitoring Using Impedance CardiographyACADEMIC EMERGENCY MEDICINE, Issue 6 2003Richard L. Summers MD Abstract The evaluation of the hemodynamic state of the severely ill patient is a common problem in emergency medicine. While conventional vital signs offer some insight into delineating the circulatory pathophysiology, it is often impossible to determine the true clinical state from an analysis of blood pressure and heart rate alone. Cardiac output measurements by thermodilution have been the criterion standard for the evaluation of hemodynamics. However, this technology is invasive, expensive, time-consuming, and impractical for most emergency department environments. Impedance cardiography (ICG) is a noninvasive method of obtaining continuous measurements of hemodynamic data such as cardiac output that requires little technical expertise. ICG technology was first developed by NASA in the 1960s and is based on the idea that the human thorax is electrically a nonhomogeneous, bulk conductor. Variation in the impedance to flow of a high-frequency, low-magnitude alternating current across the thorax results in the generation of a measured waveform from which stroke volume can be calculated by a modification of the pulse contour method. To adequately judge the possible role of this technology in the practice of emergency medicine, it is important to have a sufficient understanding of the basic scientific principles involved as well as the clinical validity and limitations of the technique. [source] Determinants of Incomplete Left Ventricular Mass Regression Following Aortic Valve Replacement for Aortic StenosisJOURNAL OF CARDIAC SURGERY, Issue 4 2005Naoji Hanayama M.D. In this prospective study, we identified the predictors of Abn-LVMI. Methods: Between 1990 and 2000, 529 patients undergoing AVR for AS had clinical and hemodynamic data collected prospectively. Preoperative and annual postoperative transthoracic echos were employed to assess left ventricular mass index (LVMI) and hemodynamics. Abn-LVMI was defined as the 75th percentile of the lowest postoperative LVMI (>128 mg/m2, n = 133). All other patients were included in the normal regression group (N-LVMI). Univariate and multivariable logistic regression analyses were used to determine the predictors of Abn-LVMI. Results: Preoperative hypertension, diabetes, coronary disease, valve size, mean postoperative gradients, effective orifice area, and patient-prosthesis mismatch (PPM, indexed EOA <0.60 cm2/m2) did not predict Abn-LVMI. By logistic regression the most important positive predictor of Abn-LVMI was the extent of preoperative LVMI, with an odds ratio of 37.5 (p < 0.0001). Survival (93.4 ± 1.8% vs 94.8 ± 2.3%, p = 0.90) and freedom from NYHA III,IV (75.0 ± 3.7% vs 76.6 ± 5.3%, p = 0.60) were similar for both groups at 7 years. Conclusions: Measures of valve hemodynamics were not important predictors of incomplete regression of hypertrophy. The extent of preoperative hypertrophy was the most important predictor, suggesting that earlier surgical intervention may reduce the extent of hypertrophy postoperatively. Furthermore, the significance of LV hypertrophy to long-term survival must be reassessed, in the absence of scientific evidence. [source] Diagnosis of arterial occlusive disease of the upper extremities: Comparison of color duplex sonography and angiographyJOURNAL OF CLINICAL ULTRASOUND, Issue 8 2003Muharrem Tola MD Abstract Purpose The aim of this study was to assess the abilities of color duplex sonography (CDUS) to detect and characterize arterial occlusive disease of the upper extremities. Methods We prospectively compared the results of CDUS with those of intra-arterial digital subtraction angiography, which were considered definitive, in patients with symptomatic arterial occlusive disease of the upper extremities. In each extremity, we visualized 9 arterial segments, which were each evaluated for stenoses and occlusions. Each segment was categorized on each imaging modality as not significantly narrowed (narrowed by <50%), significantly narrowed (narrowed by ,50% but <100%), or occluded (100%). Results We examined a total of 578 segments in 57 patients (34 men and 23 women) with a mean age of 50 years (range, 20,74 years). CDUS had a sensitivity, a specificity, a positive predictive value, a negative predictive value, and an accuracy of 98%, 99%, 97%, 99.5%, and 99%, respectively, for detecting occluded lesions and 79%, 100%, 100%, 99%, and 99%, respectively, for detecting hemodynamically significantly stenotic lesions. Notably, the sensitivity of CDUS for diagnosing significantly stenotic lesions (79%) was lower than that for diagnosing occlusive disease (98%). Conclusions With high sensitivity and accuracy rates, CDUS is a reliable screening method for detecting arterial occlusive disease of the upper extremities. This modality efficiently provides anatomic and hemodynamic data that are useful in cases of such disease. © 2003 Wiley Periodicals, Inc. J Clin Ultrasound 31:407,411, 2003 [source] Percutaneous Left and Right Heart Catheterization in Fully Anticoagulated Patients Utilizing the Radial Artery and Forearm Vein: A Two-Center ExperienceJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 3 2006TED S. N. LO M.R.C.P. Background: Stopping oral anticoagulants prior to cardiac catheterization is associated with an increased risk of thromboembolism. Performing the procedures via the femoral artery and vein without interruption of anticoagulation is associated with a high rate of major access site complications. The transradial technique for left heart catheterization is safe in fully anticoagulated patients but few data are available on the percutaneous right and left heart catheterization utilizing a combination of the radial artery and antecubital vein in this group of patients. Methods: We report our experience in 28 consecutive patients that underwent left and right heart catheterizations via this percutaneous arm approach without interruption of anticoagulation. These were compared to 31 consecutive non-anticoagulated patients that underwent the procedure via a conventional femoral artery and vein approach. Results: Arterial and venous accesses were achieved and complete angiographic and hemodynamic data obtained in all patients. There were no access site complications in the anticoagulated patients despite an International normalized ratio (INR) of 2.5 ± 0.5. Procedural duration was longer in the anticoagulated group of patients, but fluoroscopy time and patient radiation dose were similar in both groups. Conclusion: Our experience suggests that left and right heart catheterization can be safely performed in most fully anticoagulated patients using this technique with a low bleeding and thromboembolic risk and no increase in radiation exposure. [source] Comparison of the cardio-respiratory effects of methadone and morphine in conscious dogs,JOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 4 2009A. A. MAIANTE The effects of methadone and morphine were compared in conscious dogs. Six animals received morphine sulfate (1 mg/kg) or methadone hydrochloride (0.5 mg/kg [MET0.5] or 1.0 mg/kg [MET1.0]) intravenously (i.v.) in a randomized complete block design. Cardiopulmonary variables were recorded before (baseline), and for 120 min after drug administration. One outlier was not included in the statistical analysis for hemodynamic data. Morphine decreased heart rate (HR) compared to baseline from 30 to 120 min (,15% to ,26%), while cardiac index (CI) was reduced only at 120 min (,19%). Greater and more prolonged reductions in HR (,32% to ,46%) and in CI (,24% to ,52%) were observed after MET1.0, while intermediate reductions were recorded after MET0.5 (,19 to ,28% for HR and ,17% to ,27% for CI). The systemic vascular resistance index (SVRI) was increased after methadone; MET1.0 produced higher SVRI values than MET0.5 (maximum increases: 57% and 165% for MET0.5 and MET1.0, respectively). Compared to morphine, oxygen partial pressure (PaO2) was lower (,12% to ,13%) at 5 min of methadone (0.5 and 1.0 mg/kg), while carbon dioxide partial pressure (PaCO2) did not change significantly. It was concluded that methadone induces cardiovascular changes that are dose-related and is a more potent cardiovascular depressant agent than morphine in conscious dogs. [source] Hemodynamic alterations in the transferred tissue to lower extremitiesMICROSURGERY, Issue 2 2009Hiroyuki Sakurai M.D., Ph.D. A higher incidence of failure has been reported for free flaps transplanted to the lower extremities. However, the physiological background of this phenomenon has not been elucidated. We reviewed the 3-day postoperative hemodynamic data for 103 free flaps, including the in situ venous pressure (N = 103), arterial pressure (N = 53), and surface blood flow (N = 42). The cases were divided into two groups based on the recipient site, i.e., lower extremity (the LE group: N = 29) and the other (non-LE group: N = 74). The venous pressure was significantly higher in the LE group (26.6 ± 2.2 vs. 14.8 ± 1.2 mmHg), whereas the arterial pressure immediately after surgery was lower than the non-LE group. The hemodynamic data within the transferred tissues demonstrated significant differences between groups, especially in the early postoperative period. There is a possibility that the high venous pressure may aggravate the poor perfusion in tissues transferred to the lower extremities. © 2008 Wiley-Liss, Inc. Microsurgery, 2009. [source] Implant Experience with an Implantable Hemodynamic Monitor for the Management of Symptomatic Heart FailurePACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 8 2005DAVID STEINHAUS Introduction: Management of congestive heart failure is a serious public health problem. The use of implantable hemodynamic monitors (IHMs) may assist in this management by providing continuous ambulatory filling pressure status for optimal volume management. Methods and Results: The Chronicle® system includes an implanted monitor, a pressure sensor lead with passive fixation, an external pressure reference (EPR), and data retrieval and viewing components. The tip of the lead is placed near the right ventricular outflow tract to minimize risk of sensor tissue encapsulation. Implant technique and lead placement is similar to that of a permanent pacemaker. After the system had been successfully implanted in 148 patients, the type and frequency of implant-related adverse events were similar to a single-chamber pacemaker implant. R-wave amplitude was 15.2 ± 6.7 mV and the pressure waveform signal was acceptable in all but two patients in whom presence of artifacts required lead repositioning. Implant procedure time was not influenced by experience, remaining constant throughout the study. Conclusion: Based on this evaluation, permanent placement of an IHM in symptomatic heart failure patients is technically feasible. Further investigation is warranted to evaluate the use of the continuous hemodynamic data in management of heart failure patients. [source] Dynamic Changes in Lymphocyte GRK2 Levels in Cardiac Transplant Patients: A Biomarker for Left Ventricular FunctionCLINICAL AND TRANSLATIONAL SCIENCE, Issue 1 2010Raphael E. Bonita M.D., Sc.M. Abstract G protein-coupled receptor kinase 2 (GRK2), which is upregulated in the failing human myocardium, appears to have a role in heart failure (HF) pathogenesis. In peripheral lymphocytes, GRK2 expression has been shown to reflect myocardial levels. This study represents an attempt to define the role for GRK2 as a potential biomarker of left ventricular function in HF patients. We obtained blood from 24 HF patients before and after heart transplantation and followed them for up to 1 year, also recording hemodynamic data and histological results from endomyocardial biopsies. We determined blood GRK2 protein by Western blotting and enzyme-linked immunosorbent assay. GRK2 levels were obtained before transplant and at first posttransplant biopsy. GRK2 levels significantly declined after transplant and remained low over the course of the study period. After transplantation, we found that blood GRK2 signifi cantly dropped and remained low consistent with improved cardiac function in the transplanted heart. Blood GRK2 has potential as a biomarker for myocardial function in end-stage HF. Clin Trans Sci 2010; Volume #: 1,5 [source] | ||||||||||