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J Rosso

Publications and source records attributed to J Rosso.

At least 19 recordsLinked to original sources

Thallium gated SPECT: relation between immediate post-stress evolution of ejection fraction and severity of perfusion pattern.

BACKGROUND AND AIMS: A significant decrease of left ventricular ejection fraction (LVEF) at stress has been reported with 99Tc(m) gated single-photon emission computed tomography (gSPECT) in severe myocardial stunning up to 1 h after exercise. This study was designed to show whether 201Tl gSPECT can measure LVEF evolution from rest to stress in routine examination and give additional information to perfusion interpretation since acquisition starts immediately after stress test. METHODS: Post-exercise and rest 201Tl gSPECT were performed in 187 patients with suspected coronary artery disease. Myocardial perfusion was quantified by 20-segment analysis. Patients were divided into four groups according to their summed perfusion score, reversibility rate and electrocardiographic findings, i.e. in order of severity: I = normal perfusion, II = fixed defect owing to a myocardial infarction, III = full reversible ischaemia, and IV = partial reversible ischaemia. LVEF was calculated by Germano's automatic algorithm. RESULTS: Normal subjects (n = 29) and infarcted patients (n = 34) showed a significant LVEF increase between rest and stress, +7 +/- 9% and +5 +/- 7% respectively. In full reversible ischaemic patients (n = 46), stress LVEF showed no increase (+1 +/- 8%) and this group was statistically different from both group I and group II. Furthermore, when ischaemia was partially reversible (n = 31), LVEF decreased significantly (-3 +/- 8%), particularly when exercise tests were abnormal (-4 +/- 8%). Group IV was statistically different from groups I and II. CONCLUSIONS: Good agreement exists between the severity of ischaemic perfusion pattern and LVEF degradation at stress, which is consistent with previously published data using 99Tc(m) gSPECT. Additionally, the use of 201Tl for immediate post-exercise imaging allows the observation of a physiological LVEF increase in normal and infarcted patients.

Adult↗

Myocardial tracking, a new method to calculate ejection fraction with gated SPECT: validation with (201)Tl versus planar angiography.

UNLABELLED: Left ventricular ejection fraction (LVEF) and viability are essential variables for the prognosis of myocardial infarction and can be measured simultaneously by (201)Tl gated SPECT; however, most algorithms tend to underestimate LVEF. This study aimed to evaluate a new myocardial tracking algorithm, MyoTrack (MTK), for automatic LVEF calculation. METHODS: A rest/redistribution (20 min/4 h) (201)Tl gated SPECT protocol followed immediately by a (99m)Tc equilibrium radionuclide angiography (ERNA) was performed in 75 patients with history of myocardial infarction. Quality of myocardial uptake was evaluated from count statistics and automatic quantification of defect sizes and severities (CardioMatch). LVEFs were calculated both with Germano's quantitative gated SPECT (QGS) algorithm and with MTK. Briefly, the originality of this algorithm resides in the unique end-diastole segmentation, matching to a template and motion field tracking throughout the cardiac cycle. RESULTS: ERNA LVEF averaged 33% +/- 14%. QGS significantly underestimated this value at 20 min (30% +/- 13%, P < 0.001) and at 4 h (30% +/- 13%, P < 0.0001). By contrast, MTK did not miscalculate LVEF at 20 min (34% +/- 14%, probability value was not significant) though a similar underestimation occurred at 4 h (31% +/- 13%, P < 0.02). Individual differences between early and late gated SPECT values and differences between gated SPECT and ERNA values did not correlate with the extension of perfusion defects, count statistics, or heart rate. CONCLUSION: MTK algorithm accurately calculates LVEF on early/high-count images compared with ERNA [corrected], even in patients with severe perfusion defects, but tends to underestimate LVEF on delayed/low-contrast images, as other algorithms do.

Adult↗

Systematic lung scans reveal a high frequency of silent pulmonary embolism in patients with proximal deep venous thrombosis.

BACKGROUND: A high frequency of asymptomatic pulmonary embolism (PE) has been reported in patients with deep venous thrombosis (DVT) in studies of a limited number of patients using varying criteria for lung scan assessment. OBJECTIVES: To estimate the frequency of PE using systematic lung scans in a large group of outpatients with DVT and to compare the results using varying lung scan assessment criteria. METHODS: An international multicenter study comparing 2 different regimens of low-molecular-weight heparin nadroparin in DVT: perfusion lung scans were performed in 622 outpatients with no clinical indication of PE and with proximal DVT confirmed by venography. Three hundred seventy-nine of these patients underwent ventilation lung scans. High-probability (HP) scans for PE were assessed separately using either ventilation scans or chest radiographs to define mismatched perfusion defects. RESULTS: Perfusion scans showed abnormalities in 82% of the patients; 59% had segmental defects and 30% had normal scans or scans with a very low probability of PE. Depending on the criteria used, 32% to 45% had HP scans for PE; these percentages were higher in young patients. No relationship was found between extent of thrombosis and HP scans. The estimated frequency of silent PE was 39.5% to 49.5%. During a 3-month follow-up period during which the patients received therapy, the rate of PE recurrence was low (1.3%) and did not differ between patients with baseline HP scans and those with normal scans. CONCLUSIONS: Regardless of what interpretative criteria are used for assessing lung scans in PE, the frequency of silent PE is 40% to 50% in patients with DVT. A baseline lung scan may easily detect PE in these patients but is not useful for predicting early thromboembolic recurrences that may occur during therapy.

Adolescent↗

Unusual case of diagnosis of pigeon breeder's hypersensitivity pneumonitis with ventilation-perfusion lung scan.

The authors describe a patient thought to have pulmonary embolism. Results of a perfusion scan were normal, but Tc-99m DTPA aerosol ventilation lung scan showed, in successive views, decreased activity of the deposited aerosol. The lung Tc-99m DTPA clearance was measured and was markedly increased. This suggested possible hypersensitivity pneumonitis, which was later confirmed as pigeon breeder's disease. The decreased activity observed on the DTPA ventilation scan must be directed toward increased lung clearance and its measurement.

Administration, Inhalation↗

Prediction of functional recovery of viable myocardium after delayed revascularization in postinfarction patients: accuracy of dobutamine stress echocardiography and influence of long-term vessel patency.

OBJECTIVES: We sought to evaluate dobutamine stress echocardiography (DSE) for predicting recovery of viable myocardium after revascularization with cineangiography as a gold standard for left ventricular (LV) function. We studied the influence of late vessel reocclusion on regional LV function. BACKGROUND: Dobutamine stress echocardiography is a well established evaluation method for myocardial viability assessment. In previous studies the reference method for assessing LV recovery was echocardiography, long-term vessel patency has not been systematically addressed. METHODS: Sixty-eight patients with a first acute myocardial infarction (AMI) and residual stenosis of the infarct related artery (IRA) underwent DSE (mean +/- standard deviation) 21 +/- 12 days after AMI to evaluate myocardial viability. Revascularization of the IRA was performed in 54 patients by angioplasty (n = 43) or bypass grafting (n = 11). Coronary angiography and LV cineangiography were repeated at four months to assess LV function and IRA patency. RESULTS: Sensitivity and specificity of DSE for predicting myocardial recovery after revascularization were 83% and 82%. In the case of late IRA patency, specificity increased to 95%, whereas sensitivity remained unchanged. In the 16 patients with myocardial viability and late IRA patency, echocardiographic wall motion score index decreased after revascularization from 1.83 +/- 0.15 to 1.36 +/- 0.17 (p = 0.0001), and left ventricular ejection fraction (LVEF) increased from 0.52 +/- 0.06 to 0.57 +/- 0.06 (p = 0.0004), whereas in five patients, reocclusion of the IRA prevented improvement of segmental or global LV function despite initially viable myocardium. CONCLUSIONS: Dobutamine stress echocardiography is reliable to predict recovery of viable myocardium after revascularization in postinfarction patients. Late reocclusion of the IRA may prevent LV recovery and influence the accuracy of DSE.

Adult↗

Effect of delayed percutaneous transluminal coronary angioplasty of occluded coronary arteries after acute myocardial infarction.

Whether angioplasty of occluded vessels after myocardial infarction may have beneficial effects on left ventricular function remains unknown. Patients with a first myocardial infarction and thrombolytic therapy who had an occluded infarct-related vessel at delayed coronary angiography were referred systematically for an elective coronary angioplasty performed between 3 and 4 weeks after the myocardial infarction. All patients underwent stress-redistribution-reinjection thallium-201 single-photon emission computed tomography for myocardial viability assessment. Prior angioplasty, a quantitative evaluation of global and regional left ventricular function, was performed. The study group consisted of 38 patients (aged 57 +/- 10 years); 18 had anterior wall infarctions and 20 inferior wall infarctions, but before angioplasty 3 had a patent artery and were excluded. Angioplasty was successful in 30 patients. At follow-up 13 patients (43%) had an occluded coronary artery. In contrast with patients with an occluded coronary artery at follow-up, those with a patent coronary artery had no left ventricular enlargement and had an improvement in both left ventricular ejection fraction (from 48 +/- 9% to 52 +/- 9.8%, p = 0.002) and regional wall motion index (delta = +0.95 SD, p <0.01). In patients with a patent vessel at follow-up, there was a positive correlation between the number of myocardial viable segments and improvement of the infarct zone wall motion (r = 0.52; p = 0.035), and the number of necrotic segments at baseline was positively correlated to the 4-month changes in end-diastolic volume indexes (r = 0.6; p = 0.04). Thus, elective revascularization of occluded coronary arteries with viable myocardium after myocardial infarction improves left ventricular function and lessens remodeling if the artery remains patent during follow-up.

Aged↗

Usefulness of redistribution images in viability detection after acute myocardial infarction.

We undertook this study to evaluate the importance of redistribution images in thallium 201 single-photon emission computed tomography (Tl-201 SPECT) assessment of myocardial viability after acute myocardial infarction. Stress-redistribution-reinjection Tl-201 SPECT was performed in 55 consecutive patients with recent (within 1 month) acute myocardial infarction. The myocardium was divided into 16 segments and activity assessed visually with a score from 0 to 3 on stress-redistribution and stress-reinjection images. A defect was considered moderate if the stress score was 2 and severe if the stress score was 0 or 1. All moderate defects were considered viable, regardless of score on redistribution or reinjection images. Severe defects were considered viable if they were reversible (improvement of 1 score) on redistribution or reinjection images. Stress-redistribution and stress-reinjection images were visually analyzed and compared in terms of viability classification. On visual analysis, 461 segments (52%) were abnormal. One hundred eleven stress defects were moderate; of these, 28 were reversible on reinjection images only and 15 on redistribution images only. However, all of these segments were viable, regardless of the analysis chosen. Of 350 severe stress defects, 48 were reversible on reinjection and irreversible on redistribution images, and 4 were reversible on redistribution and irreversible on reinjection images. Therefore, in viability assessment, 48 segments were misclassified with stress-redistribution analysis, whereas only 4 segments were misclassified using stress-reinjection analysis. Although the usefulness of Tl-201 reinjection imaging is confirmed, redistribution images seem to be of little interest in post-myocardial infarction viability assessment.

Aged↗

Comparison between radionuclide ejection fraction and fractional area changes derived from transesophageal echocardiography using automated border detection.

BACKGROUND: Left ventricular fractional area changes (FAC) can be derived from transesophageal echocardiography using an automated border detection system. However, FAC has not yet been compared to left ventricular ejection fraction (EF) evaluated by a reference technique. The aim of this study was to correlate transesophageal echocardiography automated FAC to EF derived from radionuclide angiography to obtain a quantifying method of global left ventricular systolic function at the bedside. METHODS: Ten critically ill patients, whose lungs were mechanically ventilated, were included in this prospective study. Patients were scheduled for radionuclide EF evaluation when at least 75% of the endocardium was clearly visualized on transesophageal echocardiography. Patients with esophageal pathology or cardiac dysrhythmia were excluded. Ejection fraction derived from radionuclide angiography was measured using technetium 99m. Echocardiographic data were obtained using an ultrasound system with automated border capabilities. Simultaneous measurements of left ventricular EF and FAC were obtained for each patient, both before and after starting a dobutamine intravenous infusion to modify left ventricular contractility. RESULTS: Mean values for radionuclide EF and transesophageal echocardiography FAC were, respectively: 55% +/- 19% (range 19-89%) and 46% +/- 18% (range 17-80%). Left ventricular EF and FAC were significantly correlated (r = 0.85, SEE = 9.6%). Variations of EF and FAC, induced by dobutamine, were also correlated (r = 0.70, SEE = 4.9%). CONCLUSIONS: Fractional area changes determined by transesophageal echocardiography using automated border detection correlate well with radionuclide EF and may be used at the bedside to quantify left ventricular function in selected intensive care unit patients.

Echocardiography, Transesophageal↗

Prevention of thrombotic complications of the nephrotic syndrome by the low-molecular-weight heparin enoxaparin.

The nephrotic syndrome (NS) carries one of the highest risks of thrombotic complications. Consequently, over the last 15 years, some nephrologists have treated patients risk (i.e. those with albuminemia < 20 g/l and membranous nephropathy) with anticoagulants: either subcutaneous heparin (Kakkar protocol) or antivitamin K. Low-molecular-weight heparin (LMWH) has a longer plasma half-life and better bioavailability than standard heparin and can thus be administered as a single daily injection. LMWH also carries a lower risk of hemorrhage. We prospectively studied the safety and efficacy of the LMWH Enoxaparin for preventive anticoagulation in NS. In a preliminary study, 10 adult nephrotic patients with biological markers of thrombosis risk (severe hypoalbuminemia and/or anomalies of the fibrinolytic pathway and/or deficiency in coagulation inhibitors) were given 40 mg (4,000 U) of Enoxaparin daily for at least 3 months; 3 patients were treated for 3 months, 1 for 6 months and 6 for 12 months. Patients were assessed for silent thrombosis, using renal vein Doppler ultrasonography, lower leg vein Doppler ultrasonography and lung ventilation-perfusion scintigraphy, before entry to the trial and subsequently at 3-month intervals. As LWMH caused no obvious side effects and no thrombosis was observed during the pilot study, we then placed 55 adult nephrotic patients free of thrombosis on the same treatment. Patients were seen according to the usual calendar required by their individual illnesses. At each examination, patients were assessed for clinical signs and symptoms of thrombosis and side effects; plasma D-dimer and urinary fibrin-fibrinogen degradation products were also measured at each visit.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Prospective study of pulmonary function for cyclomegalovirus infection after renal transplantation.

Pulmonary involvement remains the main complication of cytomegalovirus (CMV) infection in renal transplantation (RT). Early diagnosis is required for the best management of patients, and preemptive therapy could be a successful approach. In order to define the predictive value of lung alveolocapillary abnormalities. We prospectively studied 26 renal transplant recipients for their diffusing capacity of carbon monoxide (DLCO) and their pulmonary clearance of a 99mTc-DTPA aerosol. Patients were studied before transplantation and then every 2 weeks up to the end of the 3rd month following RT. Viral blood cultures and serological determinations were performed every week during these first 3 months. Bronchoalveolar lavage (BAL) was done in case of CMV disease. Statistic analysis was done using Student's t-test and Pearson's chi-square test. During the 3-month follow-up, 13 patients remained free of CMV infection. Three non-infected and 8 infected patients showed DTPA clearance abnormalities (P < 0.05). Six non-infected and 7 infected patients showed DLCO disturbance (P > 0.50). DTPA clearance were significantly modified on days 45 and 60 in the infected group. Serial DTPA scanning, in association with viral blood cultures, could be a useful test to avoid unnecessary BAL in a preemptive therapy strategy.

Bronchoalveolar Lavage↗

Technetium-99m-DTPA aerosol and gallium-67 scanning in pulmonary complications of human immunodeficiency virus infection.

We retrospectively compared the results of 67Ga chest scans and 99mTc-DTPA aerosol clearance measurements with those of fiberoptic bronchoscopy in 88 patients infected with the human immunodeficiency virus. Of 100 investigations, a pulmonary infection was diagnosed in 39, mainly Pneumocystis carinii pneumonia and a noninfectious disorder was found in 42, mainly Kaposi's sarcoma and lymphocytic alveolitis. Gallium scans and DTPA clearance were abnormal respectively in 74% and 92% of infectious complications, and in 12% and 60% of noninfectious disorders. In 10 cases, DTPA clearance was accelerated, while chest x-ray, arterial blood gases and even gallium scanning were normal. A value of DTPA clearance greater than 4.5%.min-1 was both sensitive and specific for the diagnosis of Pneumocystis carinii pneumonia. The gallium scan was always normal in bronchopulmonary Kaposi's sarcoma. We conclude that in symptomatic patients: (1) DTPA clearance measurements are useful for detecting lung disease when chest x-ray and/or PaO2 are normal and (2) a gallium scan is indicated to distinguish progressive Kaposi's sarcoma from a superimposed second process when radiological abnormalities of pulmonary Kaposi's sarcoma are present.

Acquired Immunodeficiency Syndrome↗

Effects of platelet-activating factor on lung epithelial permeability in the guinea-pig.

We examined the effects of platelet-activating factor (PAF) on lung epithelial permeability by measuring the clearance of intratracheally administered 99m-technetium-labeled diethylene triamine penta-acetic acid (99mTc-DTPA) in guinea-pigs which were anaesthetised, paralysed and mechanically ventilated. The clearance of the radiolabeled tracer molecule 99mTc-DTPA from airways to the blood was expressed as changes in counts/min corrected for background. For each guinea-pig, 99mTc-DTPA clearance was assessed before and after i.v. PAF administration, when tracheal pressure had returned to near control values. Doses of 10, 50 and 100 ng/kg of PAF caused dose-dependent increases in 99mTc-DTPA clearance of 7 +/- 3%, 38 +/- 7% and 65 +/- 11% respectively. The respective effects of 0.5 mg/kg of the beta 2-adrenergic agonist salbutamol and 0.3 mg/kg of the alpha 1-adrenergic agonist methoxamine on the increase in lung epithelial permeability induced by 50 ng/kg PAF were also studied. Salbutamol significantly reduced the acute bronchoconstrictor effects of PAF, but did not affect the increase in lung epithelial permeability, which was 58 +/- 10%. Conversely, methoxamine significantly enhanced the bronchoconstrictor effects of PAF but inhibited the lung epithelial permeability increase, which was only 10 +/- 13%. In the absence of PAF, salbutamol significantly increased this permeability by 49 +/- 11%, whereas methoxamine alone slightly reduced, it by -11 +/- 4%. These results demonstrate that PAF increases lung epithelial permeability and suggest that vascular surface area recruitment may explain this increase.

Albuterol↗

Increased lung epithelial permeability in HIV-infected patients with isolated cytotoxic T-lymphocytic alveolitis.

HIV-related lymphocytic alveolitis is common in HIV-seropositive patients without lung infection or tumor. In some of them a fraction of alveolar lymphocytes are HIV-specific cytotoxic T-lymphocytes (CTL) bearing the CD8 and D44 cell surface markers and capable of killing HIV-infected alveolar macrophages. In order to evaluate the in vivo effect of these CTL on lung function, we measured the pulmonary clearance of aerosolized 99mTc-diethylene triamine penta-acetate (DTPA-CI) on 24 occasions in 22 patients with lymphocytic alveolitis. DTPA-CI has been selected as a highly sensitive test to detect injury of the lung epithelium. In 13 of the patients, we found a high DTPA-CI of 4.56 +/- 2.54%.min-1 (mean +/- SD), suggesting an increase of the epithelial permeability. The lymphocytic alveolitis was then characterized by a high cellularity, a high proportion of lymphocytes (59 +/- 18%), mainly composed of CD8+D44+ T-lymphocytes (149 +/- 109 cells/mm3), which spontaneously exhibited a cytolytic activity against the autologous alveolar macrophages in a standard 51Cr release assay. In the remaining 11 patients, DTPA-CI was normal (less than 1.78%.min-1), lymphocytic alveolitis being characterized by a low number or an absence of CD8+D44+ alveolar lymphocytes (9 +/- 13 cells/mm3) with no significant cytolytic activity. In the whole group, a significant correlation (r = 0.74, p = 0.0004) was found between the DTPA-CI and the number of CD8+D44+ lymphocytes and their cytotoxic activity against alveolar macrophages. Altogether, these results suggest that an injury of the lung epithelium could result from a HIV-specific CTL-induced immunologic conflict.

Adult↗

Intravenous digital subtraction angiography and lung imaging: compared value in the diagnosis of pulmonary embolism.

In a prospective study, 42 consecutive patients with clinically suspected pulmonary embolism underwent ventilation-perfusion (V-Q) lung imaging and digital subtraction angiography (DSA) concurrently with selective conventional pulmonary angiography (CPA). Thirty-eight studies achieved within 24 hours were reviewed independently by two pairs of observers. The findings were compared using CPA as the gold standard. V-Q lung imaging had a high percentage of indeterminate results, but none were false negative nor false positive. DSA had a lower percentage of indeterminate results but missed four of the 25 positive cases and erroneously affirmed the presence of pulmonary embolism in three cases. Therefore, the authors think that V-Q lung imaging should remain the screening examination of choice for evaluating patients with suspected pulmonary embolism.

Angiography↗

Chronic thromboembolic occlusion of main pulmonary artery does not reduce the lung clearance of 99mTc-DTPA.

In two patients with chronic unilateral massive pulmonary embolism, we studied the pulmonary epithelial permeability by measuring the clearance of inhaled and deposited 99mTc-DTPA aerosol. The clearances from the embolized lungs with complete or almost complete occlusion of a main pulmonary artery were more rapid than the clearances from the normal lung, which had an increased blood flow. This suggests that in chronic, embolized lung (1) the bronchial flow clears the inhaled solutes, and (2) there is an increase of epithelial permeability.

Adult↗

Influence of chlorpromazine on the transverse mobility of phospholipids in the human erythrocyte membrane: relation to shape changes.

The influence of chlorpromazine (CPZ) on the transverse mobility of spin-labeled phospholipids incorporated into human erythrocytes was investigated by electron spin resonance. The very slow transverse diffusion of phosphatidylcholine, as well as the absence of transverse mobility of sphingomyelin were not modified even by sublytic concentrations (approximately equal to 1 mM) of CPZ. On the other hand, the rapid outside-inside translocation of the aminophospholipids (Seigneuret and Devaux (1984) Proc. Natl. Acad. Sci. USA 81, 3751-3755), was slightly hindered in CPZ containing membranes. If the spin-labeled aminolipids were incorporated in erythrocytes and allowed to flip to the inner monolayer before CPZ addition, a fraction of the spin labels (10-15%) flipped back instantaneously from the inner to the outer leaflet, upon incubation with CPZ. Similar experiments carried out with spin-labeled phosphatidylcholine and spin-labeled sphingomyelin showed that a fraction of the spin-labeled choline derivatives flip instantaneously to the inner leaflet if CPZ was added after the spin labels. Addition of lysophosphatidylcholine had no effect on the spin-labeled phospholipid redistribution nor on their transmembrane mobility. We interpret the immediate effect of CPZ addition as being due to a reorganization of the bilayer accompanying the rapid CPZ membrane penetration, phenomenon which is independent of the CPZ effect on the steady-state activity of the 'aminophospholipid translocase', the latter effect being probably a direct CPZ-protein interaction. By comparison of the time course of phosphatidylserine transverse diffusion in control discocyte cells and in CPZ-induced stomatocytes, we infer that the difference in cell shape is not a major factor in the regulation of the active inward transport of aminophospholipids in human erythrocytes.

Chlorpromazine↗

[Aerosol pulmonary scintigraphy. A new test in the diagnostic strategy of pneumocystis carinii pneumonia in patients with acquired immunodeficiency syndrome].

In eleven patients with AIDS and suspected Pneumocystis carinii pneumonia we measured the pulmonary clearance and half-life of aerosolized 99m Tc-DTPA (diethylenetriamine pentaacetate). We correlated the half-life with gallium scans and bronchoalveolar lavages. In all nine patients with Pneumocystis, this half-life was shorter than normal value, documenting a significant increase of lung epithelial permeability (p less than 0.001). Six of these 9 patients had abnormal gallium scans. However, in two patients with normal chest X-rays, PaO2 and gallium scans, only the reduced half-life of 99mTc-DTPA evidenced acute lung disease. After treatment, the results of the DTPA half-life correlated with the presence or absence of Pneumocystis. This method is, therefore, a sensitive initial diagnostic test in patients with suspected Pneumocystis pneumonia. A short half-life should prompt bronchoalveolar lavage even when PaO2 and/or chest X-rays and gallium scans are normal.

Acquired Immunodeficiency Syndrome↗