89 research outputs found

    1004-57 Regional Left Ventricular Function by Intraventricular Ultrasound in Patients with Myocardial Infarction

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    Regional left ventricular (LV) dysfunction induced by ischemia/infarction is accompanied by increased end-systolic stress because the ischemic LV wall is unable to generate enough tension to contribute effectively to systole. To explore the possibility of assessing regional LV dysfunction as changes in LV wall stress we performed intraventricular echocardiography in 10 patients with a 6.2 french/12.5MHZ catheter at the time of cardiac catheterization. Cross-sectional images obtained at the level of the papillary muscles were analyzed by computer aided system to assess left ventricular wall thickness and radius of curvature (RC) in 16 equi-angular segments. End-systolic segmental endocardial radius of curvature divided by LV wall thickness obtained as segment area divided by the average of endo and epicardial arc lengths was utilized as an index of regional LV performance proportional to segmental LV wall stress. Percent wall thickening (WT%) was reduced (20.7±14.5%) in the territory perfused by the stenosed artery determined at catheterization, when compared with WT% obtained from territory perfused by normal coronaries (34.4±15.8%, p<0.05). In addition, systolic wall thickening was inversely related to the ratio of RC to WT at end-systole (r=0.75, %WT=65.5 – 21.4 (RCIWT), p<0.05) reflecting regional systolic dysfunction with increased circumferential end-systolic wall stress in those regions. In conclusion, intraventricular echocardiography correctly detects regional left ventricular dysfunction and its geometric consequences to local LV performance induced by ischemic myocardial damage. This technique may play an important role in monitoring myocardial injury by ischemia during invasive interventional procedures

    Mechanisms and outcome of severe mitral regulation after inoue balloon valvuloplasty

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    AbstractObjectives. The purpose of this study was to assess the incidence, mechanism and outcome of severe mitral regurgitation after treatment of mitral stenosis with percutaneous mitral valvuloplasty using the Inoue balloon.Background. Severe mitral regurgitation occurs in up to 15% of percutaneous balloon valvuloplasty procedures for acquired mitral stenosis. The incidence and mechanism of production of mitral regurgitation with the recently introduced single-ballon lnone technique have not been characterized.Methods. We examined the incidence, mechanism, predictors and outcome of severe mitral regurgitation after Inoue balloon valvuloplasty in 280 patients in the North American multicenter registry. Twenty-one patients who developed either clinically significant or angiographically severe regurgitation were identified, and their echocardiograms were reviewed to determine the mechanism of regurgitation. These patients were then compared with the remaining patients without severe regurgitation to identify predictors of this outcome.Results. The incidence of severe regurgitation in this study was 7.5%, and the mean grade of angiographic regurgitation in these patients increased from 0.9 ± 1.0 to 2.8 ± 0.7 (p < 0.05). The most common cause of regurgitation (43%) was rupture of clhordae tendineae to the anterior or posterior mitral leaflet. Tearing of a leaflet (usually the posterior one) occurred in 30% of patients; and no recognizable structural abnormality, with wide splitting of the commissures and a central regurgitant jet, was present in five patients (26%). All patients with definite posterior leaflet tears had heavily calcified leaflet. Patients who developed severe regurgitation had fewer balloon inflations and a higher grade of preexisting mitral regurgitation but were otherwish similar to the remaining patients without severe regurgitation. During 6-month follow-up, 71% of the patients with severe regurgitation were treated surgically; the grade of regurgitation decreased in four patients (19%), and five (24%) not required mitral valve replacement during 18 ± 5 month of follow-up.Conclusions. Severe mitral regurgitation is a relatively infrequent complication of Inoue balloon valvutoplasty and results from disruption of the valve integrity, chordal rapture and leaflet tearing. Careful balloon positioning may help avoid chordal rapture, and heavily calcified posterior lesflets may be at greater risk of tearing. Most patients who develop severe regurgitation will require nonemergency mitral valve replacement

    Pulmonary artery stiffness in chronic obstructive pulmonary disease (copd) and emphysema: The Multi-Ethnic Study of Atherosclerosis (MESA) COPD Study

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    Purpose: Chronic obstructive pulmonary disease (COPD) and particularly emphysema are characterized by stiffness of the aorta, due in part to accelerated elastin degradation in the lungs and aorta. Stiffness of the pulmonary arteries (PAs) may also be increased in COPD and emphysema, but data are lacking. We assessed PA stiffness using MRI in patients with COPD and related these measurements to COPD severity and percent emphysema. Materials and Methods: The Multi-Ethnic Study of Atherosclerosis (MESA) COPD Study recruited 290 participants, age 50–79 years with 10 or more packyears and free of clinical cardiovascular disease. COPD severity were defined on postbronchodilator spirometry by ATS/ERS criteria. Percent emphysema was defined as the percentage of regions of the lung &lt; -950 Hounsfield units on full-lung computed tomography (CT). PA stain was defined by the percent change in cross-sectional PA area between systole and diastole on MRI. Blood flow across the tricuspid and mitral valves was assessed by phase-contrast MRI for determination of the ventricular diastolic dysfunction (E/A ratio). Results: PA strain was reduced in COPD compared with controls (P = 0.002) and was inversely correlated with COPD severity (P = 0.004). PA strain was inversely associated to percent emphysema (P = 0.01). PA strain was also markedly correlated with right ventricular diastolic dysfunction measured by E/A ratios in the fully adjusted mix models (P = 0.02). Conclusion: PA strain is reduced in COPD, related in part to percent emphysema on CT scan, which may have implications for pulmonary small vessel flow and right ventricular function. Level of Evidence: 2 Technical Efficacy: Stage

    Myoglobin for Detection of High-Risk Patients with Acute Myocarditis

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    There is an unmet need for accurate and practical screening to detect myocarditis. We sought to test the hypothesis that the extent of acute myocarditis, measured by late gadolinium enhancement (LGE) on cardiac magnetic resonance imaging (CMR), can be estimated based on routine blood markers. A total of 44 patients were diagnosed with acute myocarditis and included in this study. There was strong correlation between myoglobin and LGE (rs = 0.73 [95% CI 0.51; 0.87], p < 0.001), while correlation was weak between LGE and TnT-hs (rs = 0.37 [95% CI 0.09; 0.61], p = 0.01). Receiver operating curve (ROC) analysis determined myoglobin ≥ 87 μg/L as cutoff to identify myocarditis (92% sensitivity, 80% specificity). The data were reproduced in an established model of coxsackievirus B3 myocarditis in mice (n = 26). These data suggest that myoglobin is an accurate marker of acute myocarditis. Graphical Abstract Receiver operating curve analysis determined myoglobin ≥ 87 μg/L as cutoff to identify myocarditis and these data were reproduced in an established model of coxsackievirus B3 myocarditis in mice: CMRI, cardiac magnetic resonance imaging; Mb, myoglobin; LGE, late gadolinium enhancement; ROC, receiver operating curve analysis

    Reduction in blood pressure for elevated blood pressure/stage 1 hypertension according to the American College of Cardiology/American Heart Association guideline and cardiovascular outcomes

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    Aims Few studies have examined the relationship of blood pressure (BP) change in adults with elevated BP or stage 1 hypertension according to the American College of Cardiology (ACC)/American Heart Association (AHA) guideline with cardiovascular outcomes. We sought to identify the effect of BP change among individuals with elevated BP or stage 1 hypertension on incident heart failure (HF) and other cardiovascular diseases (CVDs). Methods We conducted a retrospective cohort study including 616 483 individuals (median age 46 years, 73.7% men) with elevated and results BP or stage 1 hypertension based on the ACC/AHA BP guideline. Participants were categorized using BP classification at one-year as normal BP (n = 173 558), elevated BP/stage 1 hypertension (n = 367 454), or stage 2 hypertension (n = 75 471). The primary outcome was HF, and the secondary outcomes included (separately) myocardial infarction (MI), angina pectoris (AP), and stroke. Over a mean follow-up of 1097 ± 908 days, 10 544 HFs, 1317 MIs, 11 070 APs, and 5198 strokes were recorded. Compared with elevated BP/stage 1 hypertension at one-year, normal BP at one-year was associated with a lower risk of developing HF [hazard ratio (HR): 0.89, 95% CI:0.85–0.94], whereas stage 2 hypertension at one-year was associated with an elevated risk of developing HF (HR:1.43, 95% CI:1.36–1.51). This association was also present in other cardiovascular outcomes including MI, AP, and stroke. The relationship was consistent in all subgroups stratified by age, sex, baseline BP category, and overweight/obesity. Conclusion A one-year decline in BP was associated with the lower risk of HF, MI, AP, and stroke, suggesting the importance of lowering BP in individuals with elevated BP or stage 1 hypertension according to the ACC/AHA guideline to prevent the risk of developing CVD.</p

    A user friendly statistical system for polarimetric SAR Image classification.

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    En este artículo se presenta un sistema para la clasificación de imágenes SAR polarimétricas. Este sistema utiliza información contextual a través de un modelo Markoviano para las clases, además de modelos estadísticos para los datos. El sistema fue desarrollado pensando en el usuario y, por lo tanto, está íntegramente basado en interfaces gráficas. Toda vez que el usuario trata de activar una operación inválida, el sistema le informa la secuencia correcta de pasos. La funcionalidad del sistema se verifica clasificando áreas de cultivo, en una imagen SIR-C/X-SAR
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