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Simpler Method (simpler + method)
Selected AbstractsComparison of Different Methods of ST Segment Resolution Analysis for Prediction of 1-Year Mortality after Primary Angioplasty for Acute Myocardial InfarctionANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 1 2007Jakub Przyluski M.D. Background: Resolution of ST segment elevation corresponds with myocardial tissue reperfusion and correlates with clinical outcome after ST elevation myocardial infarction. Simpler method evaluating the extent of maximal deviation persisting in a single ECG lead was an even stronger mortality predictor. Our aim was to evaluate and compare prognostic accuracy of different methods of ST segment elevation resolution analysis after primary percutaneous coronary intervention (PCI) in a real-life setting. Methods: Paired 12-lead ECGs were analyzed in 324 consecutive and unselected patients treated routinely with primary PCI in a single high-volume center. ST segment resolution was quantified and categorized into complete, partial, or none, upon the (1) sum of multilead ST elevations (sumSTE) and (2) sum of ST elevations plus reciprocal depressions (sumSTE+D); or into the low-, medium-, and high-risk groups by (3) the single-lead extent of maximal postprocedural ST deviation (maxSTE). Results: Complete, partial, and nonresolution groups by sumSTE constituted 39%, 40%, and 21% of patients, respective groups by sumSTE+D comprised 40%, 39%, and 21%. The low-, medium-, and high-risk groups constituted 43%, 32%, and 25%. One-year mortality rates for rising risk groups by sumSTE were 4.7%, 10.2%, and 14.5% (P = 0.049), for sumSTE+D 3.8%, 9.6%, and 17.6% (P = 0.004) and for maxSTE 5.1%, 6.7%, and 18.5% (P = 0.001), respectively. After adjustment for multiple covariates only maxSTE (high vs low-risk, odds ratio [OR] 3.10; 95% confidence interval [CI] 1.11,8.63; P = 0.030) and age (OR 1.07; 95% CI 1.02,1.11; P = 0.002) remained independent predictors of mortality. Conclusions: In unselected population risk stratifications based on the postprocedural ST resolution analysis correlate with 1-year mortality after primary PCI. However, only the single-lead ST deviation analysis allows an independent mortality prediction. [source] A simple method to calculate the signal-to-noise ratio of a circular-shaped coil for MRICONCEPTS IN MAGNETIC RESONANCE, Issue 6 2006K. Ocegueda Abstract The introduction of the ultrafast imaging sequences has renewed the interest in development of RF coils. The theoretical frame of the SNR of MRI coils is a challenge because it requires a deep mathematical background to master the associated concepts. Here, a simpler method is proposed based on Legendre polynomials. This approximation method, together with a quasi-static approach, was used to derive a signal-to-noise ratio expression for a circular-shaped coil. Legendre polynomials were used instead of a weighting function to simplify the vector potential of the power loss, and an SNR formula was then derived. The simplified version of the SNR formula of a circular coil was compared with the weighting function-derived SNR expression using the quasi-static approach. SNR-vs.-depth plots were computed to theoretically compare both SNR formulas. Results showed a strong agreement between SNR values for the circular-shaped coil. This approach can be used as a tool to derive SNR expressions for more complex geometries. © 2006 Wiley Periodicals, Inc. Concepts Magn Reson Part A 28A: 422,429, 2006 [source] In vivo31P MRS detection of an alkaline inorganic phosphate pool with short T1 in human resting skeletal muscleNMR IN BIOMEDICINE, Issue 8 2010H. E. Kan Abstract Non-invasive determination of mitochondrial content is an important objective in clinical and sports medicine. 31P MRS approaches to obtain information on this parameter at low field strength typically require in-magnet exercise. Direct observation of the intra-mitochondrial inorganic phosphate (Pi) pool in resting muscle would constitute an alternative, simpler method. In this study, we exploited the higher spectral resolution and signal-to-noise at 7T to investigate the MR visibility of this metabolite pool. 31P in vivo MR spectra of the resting soleus (SOL) muscle were obtained with 1H MR image-guided surface coil localization (six volunteers) and of the SOL and tibialis anterior (TA) muscle using 2D CSI (five volunteers). A resonance at a frequency 0.38,ppm downfield from the cytosolic Pi resonance (Pi1; pH 7.0,±,0.04) was reproducibly detected in the SOL muscle in all subjects and conditionally attributed to the intra-mitochondrial Pi pool (Pi2; pH 7.3,±,0.07). In the SOL muscle, the Pi2/Pi1 ratio was 1.6 times higher compared to the TA muscle in the same individual. Localized 3D CSI results showed that the Pi2 peak was present in voxels well away from blood vessels. Determination of the T1 of the two Pi pools in a single individual using adiabatic excitation of the spectral region around 5,ppm yielded estimates of 4.3,±,0.4 s vs 1.4,±,0.5 s for Pi1 and Pi2, respectively. Together, these results suggest that the intra-mitochondrial Pi pool in resting human skeletal muscle may be visible with 31P MRS at high field. Copyright © 2010 John Wiley & Sons, Ltd. [source] Testing Endothelial Function of Brachial and Cavernous Arteries in Patients with Erectile DysfunctionTHE JOURNAL OF SEXUAL MEDICINE, Issue 2 2006Evsey Mazo MD ABSTRACT Introduction., There is considerable clinical and scientific evidence that endothelial dysfunction may be an important clinical link connecting erectile dysfunction (ED) with cardiovascular diseases. Aims., To modify the method of assessment of endothelial function of cavernosal arteries, to develop a new algorithm for evaluating its results, and to investigate the relationship between postocclusive changes in the diameter of brachial and cavernous arteries. Methods., The study participants were 212 patients presenting to our department complaining of ED and 40 healthy volunteers without sexual problems, which formed the control group. All patients with ED underwent complex evaluation and ultrasound assessment of postocclusive changes in the diameter of cavernosal arteries modified by us and standard ultrasound assessment of endothelium-dependent flow-mediated dilation of the brachial artery. Main Outcome Measures., As the main outcome measure, the percent of increase of the cavernosal arteries diameter (PICAD) was recorded. Results., In the patients with arteriogenic ED, PICAD values were significantly less than in other groups (P < 0.001 for pairs of comparison). At the same time there were no differences between the control group and groups of patients with psychogenic and organic nonarterial ED. The sensitivity and specificity of a PICAD value of 50% in diagnosis of arteriogenic ED were 100% and 98.2%, respectively. In all groups and in the entire sample of patients studied we did not find a correlation between PICAD and postocclusive changes in the diameter of brachial arteries. Conclusion., The method of ultrasound assessment of postocclusive changes in the diameter of cavernosal arteries is, reliable and, a, highly informative tool for diagnosis of arteriogenic ED. It cannot be substituted by techni-cally simpler method of ultrasound examination of brachial arteries, while results of the latter could help to define the necessity of performing an examination of cavernous arteries. Mazo E, Gamidov S, Anranovich S, and Iremashvili V. Testing endothelial function of brachial and cavernous arteries in patients with erectile dysfunction. J Sex Med 2006;3:323,330. [source] | ||||||||||