1,721,044 research outputs found
A META-ANALYSIS REPORTING EFFECTS OF ANGIOTENSIN-CONVERTING ENZYME INHIBITORS AND ANGIOTENSIN RECEPTOR BLOCKERS IN PATIENTSWITHOUT HEART FAILURE
Full text linkTranslation articles: G. Savarese, P. Costanzo, J.G.F. Cleland, E. Vassallo, D. Ruggiero, G. Rosano, P. Perrone-Filardi «A Meta-Analysis Reporting Effects of Angiotensin-Converting Enzyme Inhibitors and Angiotensin Receptor Blockers in Patients Without Heart Failure» J Am Coll Cardiol 2013;61(2):131-42; http://dx.doi.org/10.1016/j.jacc.2012.10.01
Predicted values of exercise capacity in heart failure: where we are, where to go
No full textCardiopulmonary exercise testing (CPET) is a procedure widely used in daily clinical activity to investigate cardiac and pulmonary disorders. Peak oxygen consumption (VO2 peak) is the most validated and clinically accepted parameter used to report aerobic capacity in healthy individuals and in different clinical settings. However, peak VO2 is influenced by several factors, whose variability is nowadays particularly evident due to the extensive use of CPET even in very young and very old subgroups of patients. Thus, its diagnostic and prognostic significance may be improved by the use of % of predicted VO2. At present, many sets of normal values are available, making the identification of the most proper max VO2 predicted value a challenging problem. In fact, normal value sets have been obtained fromstudieswhose accuracy was reduced by important limitations, such as small sample size, low grade of heterogeneity of the population enrolled, poor rigorousness of methods, or difficulty in interpreting results. Accordingly, the aim of the present review is threefold: (A) to report some illustrative cases to showhowthe choice of the normal value set can influence the report of CPET; (B) to describe the most known and used reference value sets, highlighting the main characteristics of sample population, the most important methodological aspects, and the major limitations of the studies; (C) to suggest which equation should be used, if any, and to underline its weakness
Quantitation of left ventricular asynchrony on radionuclide angiography phase images
No full textQuantitation of left ventricular (LV) asynchrony is relevant in clinical cardiology, as well as in evaluating LV mechanical properties. Radionuclide angiography (RA) phase images are extensively used, and asynchrony is usually assessed by computing the standard deviation of phase angle distribution (SD). However, SD is dependent on count statistics and does not take into account the spatial distribution of asynchrony. In this study a new index to evaluate asynchrony on phase images is presented (differential uniformity parameter, DUP). DUP is based on the frequency analysis of phase images. Diagnostic accuracy and reproducibility of either SD or DUP were tested. Reproducibility was evaluated in 15 patients studied by RA twice within a few minutes. DUP showed a better reproducibility than SD. Diagnostic accuracy was estimated in 84 patients, divided into four subgroups on the basis of coronary arteriography and contrast ventriculography findings: (a) 25 control subjects, (b) 16 patients with coronary artery disease (CAD) and normal LV wall motion, (c) 23 patients with CAD and LV hypokinesia and (d) 20 patients with CAD and LV dyskinesia. Relative diagnostic ability was assessed by comparing the areas under receiver-operating characteristic curves. DUP's area was larger than SD's when group D was tested against all the other groups (DUP's area = 87% +/- 5%, SD's area = 76% +/- 7%; P less than 0.01). Thus, our study indicates that DUP is more reproducible and more accurate than SD in identifying patients with CAD and LV dyskinesia
Non-Imaging Nuclear Monitoring of Left Ventricular Function: Twenty-Five Years of Technical Development and Clinical Experience
No full textAlthough the first non-imaging nuclear probe for clinical application was already available 25 years ago, this technique is still underused for the assessment of ventricular function. Over the years substantial technological progress rendered nuclear probes more accurate and easier to use, and so far the applicability of these devices has been evaluated in several experimental and clinical contexts. Bedside devices can be used in the evaluation of hemodynamically unstable patients and of drug therapy. In patients with several heart diseases, particularly with ischemic cardiomyopathy, accurate information on the changes in ventricular function occurring during routine activities, as well as during structured activities, can be provided using the ambulatory probes. This review will focus on the development and clinical application of these diagnostic tools
Pattern of Left Ventricular Filling in Hypertrophic Cardiomyopathy. Assessment by Dopples Echocardiography and Radionuclide Angiography
No full textAIMS:
The left ventricle in hypertrophic cardiomyopathy is anatomically and functionally non-uniform. This study was undertaken to verify whether a heterogeneity in the pattern of diastolic filling can be detected along the left ventricular inflow tract in hypertrophic cardiomyopathy.
METHODS AND RESULTS:
Early (E) and late (A) diastolic velocities were recorded by Doppler echocardiography at mitral and at mid-ventricular level in 16 normal volunteers and 30 patients with hypertrophic cardiomyopathy. Patients with hypertrophic cardiomyopathy also underwent radionuclide angiography to assess left ventricular function. E wave decreased significantly in normal volunteers (80 +/- 15 to 60 +/- 14 cm x s(-1); P<0.001), but it increased in hypertrophic cardiomyopathy (76 +/- 22 to 87 +/- 28 cm x s(-1) P=0.04), whereas the A wave decreased similarly in both. By multivariate analysis, systolic asynchrony and the ejection fraction of left ventricular lateral wall were directly related to the pattern of early filling progression (r=0.656, F=9.467; P<0.002). Moreover, systolic asynchrony showed a univariate direct correlation with changes in E velocity (r=0.42; P=0.02).
CONCLUSION:
Many patients with hypertrophic cardiomyopathy have an acceleration of filling within the left ventricular inflow tract; this phenomenon is directly related to systolic asynchrony and ejection fraction of the left ventricular lateral wall, suggesting increased suction
LOW-DOSE DOBUTAMINE ECHOCARDIOGRAPHY PREDICTING FUNCTIONAL RECOVERY AFTER CORONARY REVASCULARIZATION
No full textRelation between contractile reserve, 201-Tl uptake and collateral circulation in collateral-dependent myocardium. Implications regarding the evaluation of myocardial viabiltiy
No full text
Identification of Viable Myocardium in Patients with Chronic Coronary Artery Disease Using Rest-Redistribution Thallium-201: Optimal Image Analysis
No full textAbstract
With the widely used 50% threshold, sensitivity is high, but specificity is low in detecting viable myocardium on 201Tl SPECT. In this study, we sought to identify the best threshold for semiquantitative 201Tl analysis.
METHODS:
Rest-redistribution 201Tl SPECT was performed in 46 patients with chronic coronary artery disease before and after myocardial revascularization. Regional function was evaluated by two-dimensional echocardiography before and after myocardial revascularization using a 3-point scale (1 = normal, 2 = hypokinetic, 3 = a/dyskinetic). Myocardial segments with abnormal systolic function were defined as viable if the systolic function score decreased > or = 1 after myocardial revascularization. A second group of 12 patients with chronic coronary artery disease constituted the validation population. Sensitivity-specificity curves, as well as receiver operating characteristic curves, for rest and redistribution mages were generated by varying the 201Tl uptake threshold.
RESULTS:
A 65% threshold uptake using resting images was found to be the best for detecting a/dyskinetic segments that improve after myocardial revascularization from those that do not improve. Sensitivity was lower with a 65% threshold (75%) than with a 50% threshold (90%, p < 0.05), but specificity was higher (76% versus 26%, p < 0.05) resulting in better accuracy (76% versus 57%, p < 0.05) and positive predictive value (77% versus 55%), while the negative predictive value was not different (69% versus 75%, p not significant). The area under the receiver operating characteristic curve was significantly (p < 005) larger for rest (0.80 +/- 0.05) as opposed to redistribution (0.72 +/- 0.05) images. Similar results were obtained in a subgroup of patients with low ejection fraction. Significant correlations between the percentage of revascularized viable segments and both the change in ejection fraction and in postrevascularization ejection fraction were found. When these findings were applied in the validation group, a gain in specificity, accuracy and positive predictive value was obtained with the 65% threshold compared with the 50% threshold.
CONCLUSION:
This study demonstrated that analysis of resting images and use of the 65% 201Tl uptake threshold is preferable for separating viable from not viable dyssynergic myocardial segments in patients with chronic coronary artery disease
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