3 resultados para lateral flow platform


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INTRODUCTION: Adults with repaired tetralogy of Fallot (TOF) may be at risk for progressive right ventricular (RV) dilatation and dysfunction, which is commonly associated with arrhythmic events. In frequently volume-overloaded patients with congenital heart disease, tissue Doppler imaging (TDI) is particularly useful for assessing RV function. However, it is not known whether RV TDI can predict outcome in this population. OBJECTIVE: To evaluate whether RV TDI parameters are associated with supraventricular arrhythmic events in adults with repaired TOF. METHODS: We studied 40 consecutive patients with repaired TOF (mean age 35 +/- 11 years, 62% male) referred for routine echocardiographic exam between 2007 and 2008. The following echocardiographic measurements were obtained: left ventricular (LV) ejection fraction, LV end-systolic volume, LV end-diastolic volume, RV fractional area change, RV end-systolic area, RV end-diastolic area, left and right atrial volumes, mitral E and A velocities, RV myocardial performance index (Tei index), tricuspid annular plane systolic excursion (TAPSE), myocardial isovolumic acceleration (IVA), pulmonary regurgitation color flow area, TDI basal lateral, septal and RV lateral peak diastolic and systolic annular velocities (E' 1, A' 1, S' 1, E' s, A' s, S' s, E' rv, A' rv, S' rv), strain, strain rate and tissue tracking of the same segments. QRS duration on resting ECG, total duration of Bruce treadmill exercise stress test and presence of exercise-induced arrhythmias were also analyzed. The patients were subsequently divided into two groups: Group 1--12 patients with previous documented supraventricular arrhythmias (atrial tachycardia, fibrillation or flutter) and Group 2 (control group)--28 patients with no previous arrhythmic events. Univariate and multivariate analysis was used to assess the statistical association between the studied parameters and arrhythmic events. RESULTS: Patients with previous events were older (41 +/- 14 vs. 31 +/- 6 years, p = 0.005), had wider QRS (173 +/- 20 vs. 140 +/- 32 ms, p = 0.01) and lower maximum heart rate on treadmill stress testing (69 +/- 35 vs. 92 +/- 9%, p = 0.03). All patients were in NYHA class I or II. Clinical characteristics including age at corrective surgery, previous palliative surgery and residual defects did not differ significantly between the two groups. Left and right cardiac chamber dimensions and ventricular and valvular function as evaluated by conventional Doppler parameters were also not significantly different. Right ventricular strain and strain rate were similar between the groups. However, right ventricular myocardial TDI systolic (Sa: 5.4+2 vs. 8.5 +/- 3, p = 0.004) and diastolic indices and velocities (Ea, Aa, septal E/Ea, and RV free wall tissue tracking) were significantly reduced in patients with arrhythmias compared to the control group. Multivariate linear regression analysis identified RV early diastolic velocity as the sole variable independently associated with arrhythmic history (RV Ea: 4.5 +/- 1 vs. 6.7 +/- 2 cm/s, p = 0.01). A cut-off for RV Ea of < 6.1 cm/s identified patients in the arrhythmic group with 86% sensitivity and 59% specificity (AUC = 0.8). CONCLUSIONS: Our results suggest that TDI may detect RV dysfunction in patients with apparently normal function as assessed by conventional echocardiographic parameters. Reduction in RV early diastolic velocity appears to be an early abnormality and is associated with occurrence of arrhythmic events. TDI may be useful in risk stratification of patients with repaired tetralogy of Fallot.

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Previous studies have shown that a ratio of early transmitral flow velocity to early diastolic velocity of the mitral annulus (E/E') of > 15, obtained by tissue Doppler imaging (TDI), correlates with left ventricular filling pressure. OBJECTIVE: The aim of our study was to assess whether E/E' provides prognostic information in patients with dilated cardiomyopathy. METHODS: We studied 33 patients with dilated cardiomyopathy and mean ejection fraction of 31%. All the patients underwent routine two-dimensional and Doppler echocardiographic examination and TDI to determine early peak velocity of the mitral annulus. Pro-B-type natriuretic peptide (pro-BNP) and peak oxygen consumption (VO2max) were also measured. Patients were divided into two groups according to the value of E/E': Group I (n = 15 patients) with E/E' > or = 15 and Group II (n = 18 patients) with E/E' < 15. Patients were followed for 12+/-4 months; new hospital admission due to heart failure, heart transplantation and death were considered as cardiac events. RESULTS: There were significant differences between the two groups in conventional two-dimensional echocardiographic measurements (dimensions and ejection fraction) and Doppler parameters (mitral inflow). With regard to mitral annular velocities obtained by TDI at two different points (septum and lateral wall), the E', A' and S' velocities differed significantly between the two groups, with lower velocities in Group I. Systolic velocity measured in the lateral portion of the mitral annulus showed the most significant difference: Group I - 4.46 cm/sec versus Group II - 7.19 cm/sec, p < 0.00001. Pro-BNP was 5622 pg/ml in Group I, and 1254 pg/ml in Group II, p = 0.004. VO2 max was significantly different between the two groups: Group I - 17.6 ml/kg/min versus Group II - 22.8 ml/kg/min, p = 0.004. During follow-up, events were more common in Group I, with 9 patients (60%) having events, while in Group II, the event rate was 11.1% (2 patients), p = 0.004. CONCLUSION: The ratio of early transmitral flow velocity to early diastolic velocity of the mitral annulus is a powerful predictor of clinical outcome. Lower velocities of mitral annulus on TDI are expected in patients with E/E' > or = 15. Systolic velocities of under 5 cm/sec measured in the lateral portion of the mitral annulus appeared to be strongly related to prognosis.

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BACKGROUND: Congenital intracranial dermoid tumors are very rare. The location of these dermoid lesions in the cavernous sinus and the complexity of the operative procedure for these lesions have been noted by several authors. Dermoid tumors originating in the cavernous sinus are usually interdural, and thus blurred vision is an uncommon presentation. CASE DESCRIPTION: Herein we report the first incidental case of a cavernous sinus dermoid cyst in a 21-year-old woman. CONCLUSIONS: A literature review was done and the possible treatments and approaches for this lesion are discussed. We consider that surgical treatment is indicated in most incidental cavernous sinus dermoid lesions due to the possible symptoms related to compression or rupture leading to chemical meningitis.