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Biomedical subjects

A Manrique

Publications and source records attributed to A Manrique.

At least 37 records · Page 2Linked to original sources
PubMed2000

Effect of temporal sampling on evaluation of left ventricular ejection fraction by means of thallium-201 gated SPET: comparison of 16- and 8-interval gating, with reference to equilibrium radionuclide angiography.

Gated myocardial single-photon emission tomography (SPET) allows the evaluation of left ventricular ejection fraction (LVEF), but temporal undersampling may lead to systolic truncation and ejection fraction underestimation. The aim of this study was to evaluate the impact of temporal sampling on thallium gated SPET LVEF measurements. Fifty-five consecutive patients (46 men, mean age 62+/-12 years) with a history of myocardial infarction (anterior 31, inferior 24) were studied. All patients underwent equilibrium radionuclide angiography (ERNA) and gated SPET 4 h after a rest injection of 185 MBq (5 mCi) of thallium-201 using either 8-interval (group 1, n=25) or 16-interval gating (group 2, n=30). In group 2, gated SPET acquisitions were automatically resampled to an 8-interval data set. Projection data were reconstructed using filtered back-projection (Butterworth filter, order 5, cut-off 0.20). LVEF was then calculated using commercially available software (QGS). A higher correlation between gated SPET and ERNA was obtained with 16-interval gating (r=0.94) compared with the resampled data set (r=0.84) and 8-interval gating (r=0.71). Bland-Altman plots showed a dramatic improvement in the agreement between gated SPET and ERNA with 16-interval gating (mean difference: -0.10%+/-5%). Using multiple ANOVA, temporal sampling was the only parameter to influence the difference between the two methods. When using 8-interval gating, gated SPET LVEF was overestimated in women and underestimated in men (ERNA minus gated SPET = -4.0%+/-9.6% in women and 3.6%+/-7.6% in men, P=0.01). In conclusion, 16-interval thallium gated SPET offered the best correlation and agreement with ERNA, and should be preferred to 8-interval gated acquisition for LVEF measurement.

Adult↗
PubMed1999

Thallium-gated SPECT in patients with major myocardial infarction: effect of filtering and zooming in comparison with equilibrium radionuclide imaging and left ventriculography.

UNLABELLED: The effect of filtering and zooming on 201TI-gated SPECT was evaluated in patients with major myocardial infarction. METHODS: Rest thallium (TI)-gated SPECT was performed with a 90 degrees dual-head camera, 4 h after injection of 185 MBq 201TI in 32 patients (mean age 61 +/- 11 y) with large myocardial infarction (33% +/- 17% defect on bull's eye). End diastolic volume (EDV), end systolic volume (ESV) and left ventricular ejection fraction (LVEF) were calculated using a commercially available semiautomatic validated software. First, images were reconstructed using a 2.5 zoom, a Butterworth filter (order = 5) and six Nyquist cutoff frequencies: 0.13 (B5.13), 0.15 (B5.15), 0.20 (B5.20), 0.25 (B5.25), 0.30 (B5.30) and 0.35 (B5.35). Second, images were reconstructed using a zoom of 1 and a Butterworth filter (order = 5) (cutoff frequency 0.20 [B5.20Z1]) (total = 32 x 7 = 224 reconstructions). LVEF was calculated in all patients using equilibrium radionuclide angiocardiography (ERNA). EDV, ESV and LVEF were measured with contrast left ventriculography (LVG). RESULTS: LVEF was 39% +/- 2% (mean +/- SEM) for ERNA and 40% +/- 13% for LVG (P = 0.51). Gated SPECT with B5.20Z2.5 simultaneously offered a mean LVEF value (39% +/- 2%) similar to ERNA (39% +/- 2%) and LVG (40% +/- 3%), optimal correlations with both ERNA (r = 0.83) and LVG (r = 0.70) and minimal differences with both ERNA (-0.9% +/- 7.5% [mean +/- SD]) and LVG (1.1% +/- 10.5%). As a function of filter and zoom choice, correlation coefficients between ERNA or LVG LVEF, and gated SPECT ranged from 0.26 to 0.88; and correlation coefficients between LVG and gated SPECT volumes ranged from 0.87 to 0.94. There was a significant effect of filtering and zooming on EDV, ESV and LVEF (P < 0.0001). Low cutoff frequency (B5.13) overestimated LVEF (P < 0.0001 versus ERNA and LVG). Gated SPECT with 2.5 zoom and high cutoff frequencies (B5.15, B5.20, B5.25, B5.30 and B5.35) overestimated EDV and ESV (P < 0.04) compared with LVG. This volume overestimation with TI-gated SPECT in patients with large myocardial infarction was correlated to the infarct size. A zoom of 1 underestimated EDV, ESV and LVEF compared with a 2.5 zoom (P < 0.02). CONCLUSION: Accurate LVEF measurement is possible with TI-gated SPECT in patients with major myocardial infarction. However, filtering and zooming greatly influence EDV, ESV and LVEF measurements, and TI-gated SPECT overestimates left ventricular volumes, particularly when the infarct size increases.

Female↗
PubMed1999

201Tl and 99mTc-MIBI gated SPECT in patients with large perfusion defects and left ventricular dysfunction: comparison with equilibrium radionuclide angiography.

UNLABELLED: Left ventricular ejection fraction (LVEF) is a major prognostic factor in coronary artery disease and may be computed by 99mTc-methoxyisobutyl isonitrile (MIBI) gated SPECT. However, 201Tl remains widely used for assessing myocardial perfusion and viability. Therefore, we evaluated the feasibility and accuracy of both 99mTc-MIBI and 201Tl gated SPECT in assessing LVEF in patients with myocardial infarction, large perfusion defects and left ventricular (LV) dysfunction. METHODS: Fifty consecutive patients (43 men, 7 women; mean age 61 +/- 17 y) with a history of myocardial infarction (anterior, 26; inferior, 18; lateral, 6) were studied. All patients underwent equilibnum radionuclide angiography (ERNA) and rest myocardial gated SPECT, either 1 h after the injection of 1110 MBq 99mTc-MIBI (n = 19, group 1) or 4 h after the injection of 185-203 MBq 201Tl (n = 31, group 2) using a 90 degrees dual-head camera. After filtered backprojection (Butterworth filter: order 5, cutoff 0.25 99mTc or 0.20 201Tl), LVEF was calculated from reconstructed gated SPECT with a previously validated semiautomatic commercially available software quantitative gated SPECT (QGS). Perfusion defects were expressed as a percentage of the whole myocardium planimetered by bull's-eye polar map of composite nongated SPECT. RESULTS: Gated SPECT image quality was considered suitable for LVEF measurement in all patients. Mean perfusion defects were 36% +/- 18% (group 1), 33% +/- 17% (group 2), 34% +/- 17% (group 1 + group 2). LVEF was underestimated using gated SPECT compared with ERNA (34% +/- 12% and 39% +/- 12%, respectively; P = 0.0001). Correlations were high (group 1, r= 0.88; group 2, r = 0.76; group 1 + group 2, r = 0.82), and Bland-Altman plots showed a fair agreement between gated SPECT and ERNA. The difference between the two methods did not vary as LVEF, perfusion defect size or seventy increased or when the mitral valve plane was involved in the defect. CONCLUSION: LVEF measurement is feasible using myocardial gated SPECT with the QGS method in patients with large perfusion defects and LV dysfunction. However, both 201Tl and 99mTc-MIBI gated SPECT similarly and significantly underestimated LVEF in patients with LV dysfunction and large perfusion defects.

Electrocardiography↗
PubMed1998

[Detection of myocardial viability by echocardiography with dobutamine infusion three weeks after myocardial infarction].

The aim of this study was to assess the value of low dose dobutamine (5 and 10 gammas/Kg/min) echocardiography for the detection of hibernating myocardium in an infarcted zone three weeks after the initial infarction. The authors studied 23 patients (18 men, 15 women) with an average age of 59 +/- 8 years before and 3 months after angioplasty of the culprit artery. Segmental wall motion was assessed semi-quantitatively by the criteria of the American Society of Echocardiography. All patients had regional contractile abnormalities under basal conditions and all underwent control coronary angiography at 3 months. Improvement of segmental wall motion with dobutamine predicted improvement after revascularisation with positive and negative predictive values of 95% and 85% respectively. The sensitivity and specificity of the test calculated in the usual manner were 83% and 96% respectively. In addition, assessment of diastolic function showed reduction of the isovolumic relaxation time with dobutamine only in patients with hibernating myocardium (120 +/- 30 ms decreasing to 114 +/- 29 ms with dobutamine, p < 0.02). Low dose dobutamine echocardiography therefore allows reliable non-invasive prediction of hibernating myocardium three weeks after infarction. The reduction of isovolumic relaxation time with dobutamine could be an additional argument in favour of the diagnosis.

Aged↗
PubMed1998

Impairment of cardiac neuronal function in acute myocarditis: iodine-123-MIBG scintigraphy study.

UNLABELLED: Abnormalities of norepinephrine uptake have been found to reflect impairment in adrenergic nerve function that has influenced the cardiac outcome of patients with heart failure. The aim of this study was to explore the cardiac neuronal function by using 123I-metaiodobenzylguanidine (MIBG) scintigraphy in patients with acute myocarditis. METHODS: We studied 15 patients (age range 42 +/- 10 yr) with clinical, biological, electrocardiographic and radionuclide left ventricular ejection fraction (LVEF) (41% +/- 7%) data indicating myocarditis and 10 normal subjects (age range 36 +/- 7 yr, mean radionuclide LVEF 69% +/- 8%, p < 0.05). Fourteen patients had positive histologic findings of myocarditis and 1 had nonspecific histological data. All patients underwent planar cardiac imaging after intravenous injection of 185 MBq 123I-MIBG and right ventricular biopsy within 7 days. A chest anterior view was acquired 4 hr later. Heart-to-mediastinum ratio activity was measured, as previously described in our laboratory. RESULTS: Significant impairment of cardiac neuronal uptake of MIBG was observed and based on a reduction of heart-to-mediastinum ratio (148% +/- 16% versus 234% +/- 36%, p < 0.05). A significant correlation was observed between LVEF and MIBG uptake in patients (y = 1.58x +/- 83.7, r = 0.72, p < 0.01). CONCLUSION: Acute myocarditis is associated with an injury of the cardiac adrenergic neuronal function. In addition to the inflammatory injury of the myocytes, the impairment of adrenergic function may be involved in the cardiac pump failure induced by myocarditis.

3-Iodobenzylguanidine↗
PubMed1997

Mycobacterium mageritense sp. nov.

Strains of a new species of rapidly growing, nonphotochromogenic mycobacteria, Mycobacterium mageritense, were isolated from human sputum. The growth characteristics, acid fastness, and mycolic acids of the isolates were consistent with those of Mycobacterium species. The isolates were identified as members of a new species by performing a biochemical analysis and DNA-DNA hybridization experiments, and by comparing the sequences of several conserved genes, such as the 16S rRNA, hsp65, and sodA genes. A phylogenetic analysis in which 16S rRNA and sodA sequences were used identified M. mageritense as a novel distinct species and placed M. mageritense between members of the Mycobacterium fortuitum complex and the thermotolerant rapidly growing group. Our results demonstrate that the taxonomic value of sodA sequence analysis in the genus Mycobacterium is similar to the well-established value of 16S rRNA sequence analysis.

Bacterial Proteins↗
PubMed1996

Giant molluscum contagiosum in AIDS.

A 31-year-old man, an intravenous drug user and in an advanced stage of acquired immune deficiency syndrome (AIDS), was admitted in our Department for the treatment of skin lesions that had been diagnosed as molluscum contagiosum (MC). The clinical examination revealed the presence of multiple nodular lesions, some of which were notably large and whose color resembled that of normal skin. These lesions were localized mainly to the face, and in particular on the forehead, glabellar, malar, beard, submandibular, and neck regions (Fig. 1). Smaller, crateriform lesions were detected on the hands and the upper limbs. The lymphocyte subsets ratio was 0.02, with a CD4+ T cell count of 13 cells per mm3 (1%) and a CD8+ T cell count of 624 per mm3 (48%). The patient also had leukopenia (1690 WBC per mm3), moderate macrocytic anemia, elevation of transaminases (SGOT 105 U/L, SGPT 114 U/L) and of immunoglobulins (IgG 2660 mg/dL), and a decrease of C3 (44.2 mg/dL) and C4 (16.6 mg/dL). Histologic examination revealed the presence of typical MC lesions. In addition to an important acanthosis, it was possible to detect pyriform lobules of perfectly delineated epidermal cells, radially separated by fibrous septa that merge towards the central crater. The characteristic MC eosinophil bodies were observed in infected cells (Fig. 2). The lesions were treated with cryosurgery by spray. Many courses of therapy were given with intervals of 2-3 weeks. Every session consisted of two cycles of rapid freezing followed by a slow thaw. Many lesions disappeared with this treatment, and others were reduced in size, but total destruction of all lesions was not achieved (Fig. 3).

AIDS-Related Opportunistic Infections↗
PubMed1995

[Late manifestation of congenital intrahepatic portacaval shunt in a healthy liver].

We report the discovery of a congenital intrahepatic portocaval shunt during heart failure in a 68 year-old woman, without cirrhosis or portal hypertension. She had hepatic encephalopathy. Only 17 such cases have been reported. Their physiopathology remains unclear. Reasons for late revelation are debated. Color doppler imaging is very useful for diagnosis following and treatment of these shunts. Therapeutic options are presented.

Aged↗
PubMed1993

[Clinical course of primary non-obstructive megaureter: analysis of our series].

Due to the widespread use of obstetrical ultrasonography with concomitant fetal screening, congenital uropathies are usually diagnosed in asymptomatic neonates. The main issue is to distinguish those cases of dilatation which are clearly obstructive and need surgical treatment from those which are within the normal anatomical range. Out of 47 patients with primary megaureter, 23 were nonobstructive, these are the aim of our study. There were 16 males and 7 females; 13 were located on the left side, 7 on the right side and 3 were bilateral, adding up to 26 reno-ureteral units. Prenatal diagnosis was performed in 16 cases, the eldest patient diagnosed was nine. All infants were evaluated with ultrasonography, voiding cystourethrography, excretory urography and diuresis renography. The latter has been the most important test inducing us to adopt a conservative attitude. Differential renal function was more than 40% in 24 units and in 2 was more than 35%. Diuretic renograms were type IIIa (Dilated non obstructed) in 19 cases and IIIb (Dilated partially obstructed) in 7. There were 2 cases with vesicoureteral reflux in the contralateral system. We have performed ultrasonography and diuresis renography during the follow-up. There were 8 cases with type I (Normal) renograms and 17 cases with type IIIa. Only one patient developed an obstruction and was operated on. In every case differential renal function did not deteriorate. In 9 cases urography was performed in order to see the anatomical changes. They have remained asymptomatic during the follow-up except for two cases which presented urinary tract infection. BUN, creatinine and other biochemical figures remained within normal ranges.(ABSTRACT TRUNCATED AT 250 WORDS)

Child↗
PubMed1988

[Indications and results of surgical treatment of cavernous hemangioma of the liver].

Over a period of 6.5 years, 29 patients with liver hemangiomas have been examined. In 8 patients, the most frequent symptom was pain; in 11, a tumor was found. The diagnosis was made by means of scintigraphy with 99mTc, followed by real-time sonography, computed tomography using a contrast medium, and selective arteriography. In 16 patients (15 women, 1 man), the tumor radius was more than 6 cm and in 9 of these, more than 10 cm. In 3 patients, a left lobectomy was carried out, and in 5 a right lobectomy; in an additional 5 patients, a extended right lobectomy (three segments excised) was done. In the rest, a medial lobectomy, a segmentectomy on the left side, or a segmentectomy on the right was performed. The only complications observed in the whole series were: pleural effusion (1 case), subphrenic abscess (1), and transitory biliary fistula (1). All hemangiomas with a radius of more than 10 cm should be removed operatively, as should smaller symptomatic hemangiomas and tumors that are not clearly benign.

Adult↗