Hepatic iron overload in thalassemic patients: proposal and validation of an MRI method of assessment.

BACKGROUND: A simple, accurate, reproducible and noninvasive method of body iron overload assessment would be of great clinical use. Objective. The purpose of the study was the implementation of a 0. 5-T MRI method for liver iron overload measurement. MATERIALS AND METHODS: Thirty patients with thalassemia major took part in the study. Liver and paraspinal muscle signal intensity (SI) measurements were performed on T1-weighted images and normalized on a standard phantom, and a subjective hemochromatosis grading scale was made on both T1- and T2-weighted images. Serum ferritin levels and tissue iron from liver biopsy specimens were determined for comparison. RESULTS: A close correlation was found between bioptic liver iron and both the liver-to-phantom SI ratio (r = -0.88) and the subjective grading scale (rho = 0.89). Serum ferritin correlated poorly with liver iron deposition, whether assessed by biopsy (r = 0. 62) or MRI (r = -0.69). CONCLUSIONS: Both the subjective and the quantitative MRI methods proposed here are clinically valuable, with the former being adequate for a gross, the latter for an accurate estimation of tissue iron overload.

Left atrial thrombus and spontaneous echo-contrast in nonanticoagulated mitral stenosis. A transesophageal echocardiographic study.

OBJECTIVE: The aim of the study was to investigate if evidence at transthoracic echocardiography (TTE) of left atrial (LA) thrombus and LA spontaneous echo-contrast (LA SEC), which are potential precursors of embolization, can be predicted by clinical and TTE variables in nonanticoagulated mitral valve stenosis (MS). DESIGN: Clinical (age, NYHA class, rhythm, previous embolization) and TTE variables were related to transesophageal echocardiography (TEE) evidence of LA thrombus and/or LA SEC. SETTING: Nonanticoagulated MS was the setting. PATIENTS: Fifty-nine patients had MS, and they were not receiving anticoagulant or antiplatelet therapy (24 in sinus rhythm and 35 in atrial fibrillation). Previous arterial embolization had occurred in 12 patients (20.3 percent). MEASUREMENTS: The following TTE variables were analyzed: mitral orifice area (pressure half-time method), mitral gradient (Bernouilli's equation), LA end-systolic area, and mitral regurgitation (color Doppler grading). LA thrombus and LA SEC were analyzed by monoplane TEE. RESULTS: LA thrombus was found by TEE in 12 patients (20.3 percent). Of these 12, 11 (91.6 percent) were in atrial fibrillation. LA SEC was found by TTE in 2 patients (3.5 percent) and by TEE in 40 (67.8 percent) (p < 0.001). Previous embolization had occurred only in patients with LA SEC, of whom 5 had and 7 did not have LA thrombus. Patients with LA SEC, compared with those without LA SEC, were characterized by more frequent advanced NYHA class, atrial fibrillation, smaller mitral valve area, and larger LA size. By multivariate regression analysis, atrial fibrillation and LA end-systolic area were factors related to both LA thrombus and LA SEC, whereas mitral area was related only to LA SEC. However, whereas LA SEC was accurately predicted by the presence of atrial fibrillation (sensitivity: 87.5 percent; specificity: 100 percent) and a LA area > or = 30 cm2 (sensitivity: 72.5 percent; specificity: 89.5 percent), among patients with LA SEC no clinical or TTE variable accurately identified those with actual LA thrombus. CONCLUSIONS: TEE is not necessary in many patients with MS in order to recognize LA SEC. However, when actual LA thrombus detection is necessary for clinical decision making, TEE should be performed.

[Analysis of the segmentary motility of the left ventricle by dimensional echocardiography in ischemic cardiopathy]. / Análisis de la movilidad segmentaria del ventrículo izquierdo por ecocardiografia bidimensional en la cardiopatía isquémica.

In 30 patients with clinical diagnosis of ischemic heart disease, we correlated the segmental mobility of left ventricular walls as estimated by two-dimensional echocardiography (2-D Echo), and coronary arteriography findings. In consideration to the distribution of the coronary arteries, the left ventricular circle was divided in 5 sections: anterior interventricular septum, anterior wall, lateral wall, posterior wall and posterior interventricular septum. Each one of these walls were divided in three levels: basal, mid and apical, integrating 15 segments. Potentially we could study 450 segments, but it was only possible to examine 444 (98.6%) by 2-D Echo. In 26 patients in whom the coronary arteriography demonstrated ischemic heart disease, the 2-D Echo showed 100% sensitivity and specificity in recognizing the disease. In respect to the number of obstructed vessels, the sensitivity was the same and the specificity 66.6%. Regarding the location of the obstruction; the results of sensitivity and specificity were: for the left anterior descending 96% and 80% respectively, for the left circumflex 87% and 92% and for the right coronary artery 95% and 90%. In regard to the level of obstruction (proximal, mid or distal) the values were 88.6% and 81.8%. Finally, to recognize the presence of significant obstruction (75% or more) the sensitivity of 2-D Echo was 95% and the specificity 76.1%. It is concluded that the 2-D Echo is useful for the diagnosis of coronary artery disease, the number of obstructed vessels, the location, the level and the degree of obstruction.(ABSTRACT TRUNCATED AT 250 WORDS)