The value of immunoscintigraphy in the detection of recurrent colorectal cancer.

The aim of this prospective study was to determine whether anti-carcinoembryonic antigen (anti-CEA) scintigraphy is a useful additional technique in the diagnosis recurrence of colorectal cancer. Forty patients with suspected recurrence of colorectal cancer, underwent immunoscintigraphy (IS) and helical computed tomography (CT) in the 2 weeks before surgery. Surgical findings were used to evaluate the performance of the imaging techniques. Suspected areas on IS and CT were systematically explored. Helical CT was found to be superior to IS for the liver, the sensitivity and specificity of CT being 100% and 90%, respectively, vs 53% and 100% for IS. However, IS was better than CT for the detection of extra-hepatic abdominal recurrence: sensitivity and specificity of IS were 100 and 82% respectively vs 33 and 82% for CT. Seven cases of peritoneal carcinomatosis were overlooked by helical CT. Our results indicate that IS improves detection of extra-hepatic abdominal recurrence of colorectal cancer. Immunoscintigraphy is valuable as a guide to the treatment strategy and operative procedures.

Thrombolysis or heparin therapy in massive pulmonary embolism with right ventricular dilation: results from a 128-patient monocenter registry.

STUDY OBJECTIVES: To assess the potential benefit of thrombolysis in patients with massive pulmonary embolism (PE) with stable hemodynamics and right ventricular dysfunction. DESIGN: Retrospective, cohort study. SETTING: University-based, tertiary referral medical center. PATIENTS: One hundred fifty-three consecutive patients with massive PE from January 1992 to December 1997 treated with heparin or thrombolysis. MEASUREMENTS AND RESULTS: Massive PE was confirmed by perfusion lung scan or pulmonary angiography. Right ventricular dysfunction was assessed by echocardiography (right ventricular/left ventricular [RV/LV] diastolic diameter ratio > 0.6) in all patients. In order to study a homogeneous population, 64 patients treated with thrombolysis (group 1) were matched on baseline RV/LV diameter ratio to 64 patients treated with heparin (group 2). Perfusion lung scan was repeated at day 7 to day 10. Mean relative improvement in perfusion lung scans was higher in group 1 than group 2 (54% vs 42%, respectively). PE recurrences were the same in both groups (4.7%; n = 3). There were no bleeding complications and no deaths in group 2. Conversely, in group 1, 15.6% (n = 10) of patients suffered from bleeding (4.7%; n = 3 with intracranial bleeding) and 6.25% (n = 4) of them died. CONCLUSIONS: The results of this monocenter registry do not support the indication for thrombolysis in patients suffering from massive PE with stable hemodynamics and right ventricular dysfunction. Appropriate therapy in such patients still remains unknown. Further prospective randomized trials should be performed.

Technetium-99m ECD single photon emission computed tomography in brain trauma: comparison of early scintigraphic findings with long-term neuropsychological outcome.

OBJECTIVE: The aim of this study was to assess the prognostic value of early brain scintigraphy in head injury in relation to long-term neuropsychological behavior. Twenty-four patients underwent technetium-99m (Tc-99m) ethyl cysteinate dimer single photon emission computed tomography (SPECT) within 1 month of the trauma. Scintigraphic abnormalities were evaluated both visually and semiquantitatively using the brain-to-cerebellum ratio method. The clinical neuropsychological investigation was conducted to evaluate abnormalities related to motor deficit, frontal behavior, and memory and language disorders. All patients had abnormalities on SPECT scan. One year after trauma, 14 patients (58%) had neuropsychological sequelae. The brain-to-cerebellum ratios in the left basal ganglia and brain stem were significantly decreased in patients with memory disorders (P = .03 and P = .02, respectively). Moreover, SPECT visual analysis indicated that low uptake in the basal ganglia, thalamus, and brain stem was associated with subsequent motor deficit, frontal behavior, and language and memory disorders. The authors conclude that brain SPECT can be valuable in predicting the neuropsychological behavior of survivors of severe head injury.

[Diagnostic value of physical examination and electrocardiogram in the initial evaluation of heart murmurs in children]. / Valeur diagnostique de l'examen clinique et de l'électrocardiogramme dans l'évaluation initiale d'un souffle cardiaque de l'enfant.

OBJECTIVE: To investigate the diagnostic value of the physical examination and electrocardiogram in the evaluation of heart murmur in new patients referred to the pediatric cardiologist. METHOD: From 1 April to 30 September 1998, all consecutive patients referred to the pediatric cardiology clinic for evaluation of heart murmur were included. They were prospectively categorized with no heart disease, possible heart disease or definite heart disease based on history and physical examination. They then underwent electrocardiogram with which the diagnosis was reevaluated by the pediatric cardiologist. Lastly, a doppler-echocardiography was systematically performed. RESULTS: In 120 children aged four days to 14 years (median: ten months), 72 (60%) showed abnormalities on doppler-echocardiography and 48 (40%) no heart disease. After physical examination, 52 patients were categorized with no heart disease: 45 patients had a normal doppler-echocardiography; in three of them, the diagnosis was incorrectly modified to possible heart disease on the basis of the electrocardiogram. In the other seven children, the electrocardiogram was normal and the doppler-echocardiography revealed minor (n = 5) or moderate (n = 2) heart defects. Nineteen patients were suspected of having possible heart disease, no diagnosis was modified after analysis of the electrocardiogram and six had normal doppler-echocardiography; 49 patients were correctly diagnosed as having definite heart disease. The sensibility of the physical examination was 90.3%, the specificity was 93.8%, the positive predictive value 95.6% and the negative predictive value 86.5%. CONCLUSION: The electrocardiogram is of no help in the discrimination between heart disease and no heart disease in children referred to the pediatric cardiologist for a cardiac murmur. The physical examination is able to differentiate children with or without heart disease in most of the cases.

Localization of the ventricular preexcitation site in Wolff-Parkinson-White syndrome with Doppler tissue imaging.

PURPOSE: The objective of this study was to evaluate the ability of Doppler tissue imaging (DTI) to localize the ventricular emergence site of accessory atrioventricular pathways (Wolff-Parkinson-White syndrome). METHODS: Thirty-three patients were studied prospectively by Doppler tissue imaging (128XP and Sequoia 256 echocardiographic systems; Acuson, Mountain View, Calif) before investigation of Wolff-Parkinson-White syndrome and after radiofrequency ablation of the accessory pathways. The normal appearance of the ventricular contractions was defined in a group of 10 control subjects. The preexcitation zone was determined as a zone of maximum acceleration in "DTI acceleration mode" or as a coded contraction zone in "DTI velocity mode," at the time of the delta wave or before the onset of the QRS complex. RESULTS: The earliest ventricular activation site was correctly localized for 12 of the 15 left-sided pathways (8 anterior or anterolateral, 2 lateral or posterolateral, 2 inferior). When wall motion abnormalities were detected in the left ventricle by DTI, the left-sided localization was confirmed by electrophysiologic exploration. For the right-sided pathways, the localization was correct in only 4 of 11 cases (3 posteroseptal and 1 anterolateral). After effective ablation in all patients, the abnormalities corresponding to the electrophysiologic data disappeared totally in only 11 of 16 patients. CONCLUSION: In the presence of Wolff-Parkinson-White syndrome, DTI localizes contraction abnormalities associated with early activation of a part of the ventricle. However, the interpretation of the images remains difficult because the normal coding of the contraction of the ventricular walls depends on the incidence for which they are investigated. This noninvasive examination seems to be an effective tool for localizing the left-sided accessory pathways of the left ventricle, in particular in the anterior, anterolateral, or inferior walls.

Fourier phase analysis of SPECT equilibrium radionuclide angiography in symptomatic patients with mitral valve prolapse without significant mitral regurgitation: assessment of biventricular functional abnormalities suggesting a cardiomyopathy.

BACKGROUND: Ventricular premature beats are common in patients with mitral valve prolapse (MVP). The purpose of this study was to determine whether symptomatic patients with MVP had certain functional characteristics and if ventricular arrhythmia (VA) could be explained by functional extravalvular abnormalities. Single photon emission computed tomography equilibrium radionuclide angiography with Fourier phase analysis was preferred to the planar radionuclide method. Only patients without significant mitral regurgitation were studied. METHODS AND RESULTS: A total of 23 symptomatic patients with MVP (13 men, 10 women, mean age, 47+/-14 years) without mitral regurgitation underwent single photon emission computed tomography equilibrium radionuclide angiography. Symptoms were present in 20 patients, and VA was present in 14 patients. Ejection fraction, regional wall motion, and Fourier phase analysis were examined in both ventricles and compared with results for normal subjects. Ventricular abnormalities were observed in 20 (87%) patients: decreased left ventricular and right ventricular ejection fractions, increased standard deviations of the mean phase and focal wall motion, and/or delayed phase abnormalities. Abnormalities were less frequent but more marked in the right ventricular free wall, the infundibulum, or the septum compared with left ventricular delayed abnormalities, which were more frequent but limited. In 12 of 14 patients with VA, phase-delayed areas were observed in the ventricle where the origin of ventricular premature beats was suspected on the basis of their electrocardiographic morphologic features. A relation was found between late potentials and delayed-phase areas (right ventricle or septum) and left bundle branch block morphologic features of VA. CONCLUSIONS: Symptomatic patients with MVP frequently have ventricular dysfunction in 1 or both ventricles, sometimes limited but more marked in the presence of severe VA even without significant mitral regurgitation, suggesting structural modification. The use of a sensitive, accurate, and 3-dimensional method such as single photon emission computed tomography equilibrium radionuclide angiography may be of interest for a noninvasive investigation, especially in young symptomatic patients with MVP and VA.

Doppler monitoring of the vascular resistance in the lower limbs during dipyridamole test in preparation for myocardial tomoscintigraphy.

OBJECTIVE: the aim of this work was to quantify the intensity of the vasodilation induced by dipyridamole used to simulate a stress test during a myocardial tomoscintigraphy. METHODS: Doppler measurements of the femoral artery and the thoracic aorta were made on 26 patients (11 men, 15 women), using transducers attached to the skin, measurements being performed every 2 min during the 10 min of the stress test. The following parameters were measured: (a) the vascular resistance index of the lower limbs defined as R(fa)=D/S with S and D, respectively, the maximum amplitude of the systolic wave and the maximum amplitude of the diastolic reflux measured on the Doppler femoral spectrogram; (b) the aortic and femoral blood flows obtained from the mean velocity on the Doppler spectrogram. RESULTS: 14 of the 26 patients (54%) showed a significant vasodilation (i.e. a decrease of R(fa) of more than 10%). Eighty-seven percent of the patients with a positive myocardial scintigraphy showed a vasodilation. Sixty-six percent of patients who had prior vasodilator treatment showed no vasodilation. A slight decrease in blood pressure was observed for vasodilated patients but also for non-vasodilated patients. The aortic flow increased slightly for all patients. CONCLUSIONS: Doppler monitoring of femoral vascular resistance is a useful method for quantifying the dipyridamole-induced vasodilation, and hence the stress level upon which the diagnostic efficiency of myocardial scintigraphy is depending. Our study demonstrates that testing with dipyridamole was inconclusive in 66% of patients who had already vasodilator treatment.

Evaluation of left ventricular systolic function by 3D echocardiography: a comparative study with X-ray angiography and radionuclide angiography.

OBJECTIVE: the aim of this study was to evaluate left ventricular systolic function by 3D ultrasound as compared to with radionuclide and X-ray angiographies. METHODS: one hundred and four patients were examinated by 3D ultrasound (3D-US) but only 72 examinations were successful. Thirty patients were investigated by 3D-US, M-mode US or bidimensional (2D) US, and X-ray angiography (group I) and 42 patients were investigated by 3D-US, M-mode, or 2D, and radionuclide angiography (group II). RESULTS: the correlation between ejection fraction (EF) evaluated by 3D-US and reference methods was found to be good and similar for the two groups (r=0.75; P<10(-4) for group I and r=0.76; P<10(-4) for group II). The correlation between EF calculated by conventional 2D-US and by reference methods was lower (r=0.60; P=0.04 for group I and r=0.54; P=0.001 for group II). The correlation between EF evaluated by 3D- and 2D-US was modest (r=0. 55; P=0.001 for the whole group). The correlation between 3D-US left ventricle end-diastolic volume (EDV) and end-systolic volume (ESV) and those evaluated by X-ray angiography was also modest (r=0.33; NS for EDV and r=0.60; P<10(-4) for ESV). The correlations between EDV and ESV in 3D-US, and those evaluated from radionuclide angiography were fairly good and in the same range (r=0.76; P<10(-4) and r=0.87; P<10(-4)). CONCLUSION: the 3D-US system using a rotating probe in an apical view is valuable for evaluation of left ventricular systolic function.

[Evolution of ventricular septal defects. Relation to echocardiographic anatomy]. / Evolution des communications interventriculaires membraneuses. Relation avec l'anatomie échocardiographique.

The aim of this study was to analyse the outcome of membranous ventricular septal defects (VSD) with respect to the echocardiographic data obtained during the first year of life. This retrospective series included patients born between January 1st 1986 and December 31st 1995, in the Indre et Loire department, with membranous ventricular septal defects alone or associated with minor abnormalities. The initial echocardiography, an echocardiography performed 2 to 6 months later, one a year later and the final echocardiography were compared. Three groups of VSD were constituted according to their diameter: group I (< or = 3 mm), group II (3-6 mm), and group III (> 6 mm). Depending on the outcome, the patients were classified as spontaneous closure (group A), surgical closure (group B) or persistent VSD (group C). The population comprised 84 children. There were 6 spontaneous deaths, three of which were unexplained, and 7 children were lost to follow-up. After the initial echocardiography, the VSD were classified as group I (38%), group II (26.2%) and group III (35.7%). After the second echocardiogram, 24 VSD changed group (31.5%), by increase (N = 10) or decrease (N = 14) in diameter. Aneurysms of the membranous septum were observed during the first two echocardiographies in 31.2% and 79.3% of VSDs of group I, 31.8% and 70% of VSDs of group II and 6.6% and 3.3% of VSDs of group III (p < 0.01). The average follow-up was 3.1 years (range 1 month-10 years). In group A (N = 22), the mean age of closure of the VSD was 26 months (3 months-7 years). In group B (N = 28), surgery was undertaken at an average age of 10 months (range 3 months-5 years). In group C (N = 21), the VSDs were classified as group I (N = 19) or group II (N = 2) at the last echocardiography. The frequency of aneurysms of the membranous septum in groups A, B and C were respectively 100%, 7.1% and 66.6% (p < 0.01). At the second echocardiographic examination, a significant relationship (p < 0.001) was observed between the diameter of the VSDs and their outcome. The VSDs of group A were associated with aneurysms of the membranous septum more often than those of group C (p < 0.005). The authors conclude that surgery is required in about one third of membranous VSD. At medium term, the others either close spontaneously or become smaller in comparable numbers. The outcome is directly related to the diameter of the VSD and the development of an aneurysm of the membranous septum. During the first 6 months, the dimensions of membranous VSDs change in about 30% of cases with an increase in frequency of aneurysms of the membranous septum.

[Comparative study of post-infarction myocardial viability after fibrinolysis by stress tomoscintigraphy and echography: can viability be detected without ischemia?]. / Etude comparée de la viabilité du myocarde en post-infarctus après fibrinolyse par tomoscintigraphie et échographie de stress: peut-on détecter la viabilité sans l'ischémie?

The objectives of this prospective study was to define the comparative ability of stress myocardial scintigraphy and dobutamine stress echocardiography to demonstrate post-MI myocardial viability, assessed on the functional recovery in terms of improvement of global and segmental kinetics by cardiac gamma-angiography after revascularization. 18 patients (11 anterior MI, 7 lateral or inferior MI) and 162 segments were analysed semiquantitatively. All patients with persistent significant stenosis underwent secondary revascularization of the artery responsible for myocardial infarction. The prevalence of viability was high, as only 34% of segments initially presented a segmental kinetic abnormality and contraction was improved at 6 months in 54% of cases. Stress scintigraphy and dobutamine echocardiography detected viability with a sensitivity of 96% and 70%, a specificity of 88% and 82%, a positive predictive value of 89% and 77% and a negative predictive value of 95% and 76%, respectively. Only the wall score index with low-dose dobutamine was correlated with the ejection fraction at 6 months. Stress echocardiography is a more reliable predictor of the degree of functional recovery after revascularization. Scintigraphy visualizes much more extensive abnormalities than echocardiography. This often corresponds to ischaemic territories with normal contraction under baseline conditions and low doses of dobutamine. It therefore seems preferable both examinations for optimal assessment of thrombolized patients following myocardial infarction.

Diagnosis of arrhythmogenic right ventricular cardiomyopathy by fourier analysis of gated blood pool single-photon emission tomography.

To evaluate the diagnostic performance of Fourier phase analysis of gated blood pool single-photon emission computed tomography (GBP SPECT) in arrhythmogenic right ventricular (RV) cardiomyopathy, 18 patients with confirmed arrhythmogenic RV cardiomyopathy underwent GBP SPECT and x-ray cineangiography. Results were compared with data obtained with GBP SPECT in 10 control subjects. This 3-dimensional method demonstrated good correlation with cineangiography for measurements of RV enlargement and extent of the disease; RV and left ventricular segments were analyzed with the same accuracy. Tomographic abnormalities were significant decreased RV ejection fraction, RV dilatation, nonsynchronized contraction of the ventricles, increased RV contraction dispersion, presence of segmental RV wall motion disorders and/or phase delays, and occasionally regional left ventricular abnormalities. RV-delayed phase areas were always present in our population. A scoring system with RV criteria was proposed to diagnose RV disease. Because Fourier analysis of GBP SPECT provides ventricular morphologic information for the right ventricle with the same accuracy as for the left ventricle, it may replace planar radionuclide studies. Therefore, this method is helpful in patients with a strong clinical suspicion of arrhythmogenic RV cardiomyopathy, and should be used as a screening method before right ventriculography.

[Comparative efficacy and risks of low molecular weight heparins and thrombolysis in massive pulmonary embolism without cardiogenic shock]. / Efficacité et risques comparés des héparines de bas poids moléculaire et de la thrombolyse dans l'embolie pulmonaire massive sans état de choc. A propos de 62 patients.

The aim of this retrospective study was to assess pulmonary reperfusion by scintigraphy, the risks of recurrent embolism and of bleeding complications at the 7th day and 3rd month in 2 groups of patients admitted to hospital for massive pulmonary embolism without cardiogenic shock treated by intravenous thrombolysis (Group I) and by subcutaneous low molecular weight heparin (Group II) paired by Miller's index. The basal characteristics of the two groups, each comprising 31 patients, were comparable with respect to the severity of the pulmonary embolism with an average global scintigraphic defect of 40.6 +/- 13.5% in Group I and 39 +/- 13.7% in Group II. The scintigraphic changes at the 7th day were comparable with a relative improvement of 55 and 51% respectively and at 3 months of 74% in both groups. There was no significant difference in terms of recurrence of embolism (3 versus 0% at the 7th day and 3% in each group at 3 months) or of bleeding complications (13 and 10% at the 7th day and 10 and 6% at 3 months respectively). Low molecular weight heparin seems to be as effective as intravenous thrombolysis for the treatment of massive pulmonary embolism without shock. This result requires confirmation by a large scale prospective randomised trial.

[Value of tomoscintigraphy with Fourier analysis in the diagnosis of arrhythmogenic right ventricular cardiomyopathy]. / Intérêt de la tomoscintigraphie cavitaire avec analyse de Fourier dans le diagnostic de cardiomyopathie arythmogène du ventricule droit.

ECG gated blood pool tomography has been performed in sixteen patients with right ventricular arrhythmias in whom the diagnosis of arrhythmogenic right ventricular cardiomyopathy was made based on the finding of abnormalities on contrast angiography. They were compared both to control subjects and to patients with primary dilated cardiomyopathy. Thick slices of ventricles were obtained throughout the cardiac cycle in three orthogonal planes: horizontal long axis and short axis thick slices for analysis of right and left ventricular regional wall motion abnormalities and analysis of the spread of the contraction by means of Fourier phase imaging, vertical long axis slices (one for each ventricle) for ejection fractions, because of easy and reproducible determination of valvular planes and analysis of all right ventricular segments, especially the pulmonary infundibulum. Five typical right ventricular abnormalities were seen: decreased ejection fraction (32 +/- 15% vs 55 +/- 3% in control; p < 0.001), increased diameter (ratio of right to left diameters = 1.2 +/- 0.3 vs 0.9 +/- 0.1; p < 0.01), global delayed contraction versus that of the left ventricle (22 +/- 20 degrees vs -2 +/- 6%; p < 0.01), increased dispersion of contraction (32 +/- 16 degrees vs 13 +/- 4 degrees; p < 0.01) and presence of segments with decreased and/or delayed contraction. Right ventricular disease was observed in all the patients: localized form (56%), diffused form (44%). This method provides accurate functional data for diagnosis and follow-up of patients. In future, this wall motion evaluation method may replace planar nuclear angiography as myocardial SPECT have replaced myocardial planar scintigraphy.

Free-floating thrombus and embolic risk in patients with angiographically confirmed proximal deep venous thrombosis. A prospective study.

BACKGROUND: A free-floating thrombus (FFT) is often considered to be a risk factor for pulmonary embolism (PE), despite adequate anticoagulation therapy, in patients with proximal deep venous thrombosis. METHODS: Ninety-five patients underwent prospective assessment according to the presence (FFT group [n = 62]) or absence (occlusive thrombus group [n = 28]) of an FFT. On day 1, color venous duplex scanning, venography (reference method), perfusion lung scanning, and, if results of the lung scan were abnormal, pulmonary angiography were performed. On day 10 (range, days 9-11), the lung scan was repeated, as well as pulmonary angiography if the lung scan demonstrated impairment. A 3-month clinical follow-up visit was scheduled. Five patients were retrospectively excluded from analysis for uncertain diagnosis of FFT. Patients were treated with intravenous unfractionated heparin sodium adjusted for activated partial thromboplastin time (n = 1) or subcutaneous low-molecular-weight heparin (n = 89) (nadroparin calcium, 225 Institut Choay factor Xa inhibitory units per kilogram for 12 hours). Warfarin sodium therapy was initiated on day 3 (range, days 2-4). RESULTS: Both groups were well-matched according to age, sex, risk factors, and delay from onset of symptoms to treatment. Positive and negative predictive values of color venous duplex scanning for the diagnosis of an FFT were 91% and 55%, respectively. On admission, PE prevalence was 64% in the FFT group (40 of 62 patients) and 50% in the occlusive thrombus group (14 of 28 patients) (P = .19). Two patients were excluded on follow-up analysis (range, days 9-11) for preventive vena cava filtering (due to major bleeding in 1 and cholecystectomy in the other); the recurrent rate of PE was 3.3% in the FFT group (2 of 61 patients) and 3.7% in the occlusive thrombus group (1 of 27 patients). No symptomatic recurrent PE occurred between day 10 (range, days 9-11) and 3 months. Four patients died of evolutive neoplasm after hospital discharge. CONCLUSIONS: No higher risk for PE was observed in patients with free-floating proximal deep venous thrombosis; anticoagulant therapy should prevent recurrent PE in such patients.

[Echocardiographic Doppler study of left ventricular filling in the diagnosis of minimal or moderate rejection in cardiac transplantation]. / Etude du remplissage ventriculaire gauche par écho-Doppler cardiaque pour le diagnostic de rejet aigu minime ou modéré dans les transplantations cardiaques.

The study of left ventricular filling by Doppler echocardiography may be a non-invasive diagnostic method of detection of acute rejection of cardiac transplants. The aim of this study was to assess the value of the method for diagnosis of minimal to moderate rejection (grades 1 to 3 of the Billingham classification). A total of 466 Doppler echocardiographic studies were performed in 23 cardiac transplantation patients (21 men, mean age 49.3 +/- 10 years) with endomyocardial biopsy as the reference method for the diagnosis of rejection. Over a follow-up period of 18.5 +/- 10 months, 22.7% of biopsies showed minimal or moderate rejection. The Doppler measurements of the isovolumic relaxation period and peak early diastolic (E) velocity with respect to the mitral velocity-time integral were no different in cases of acute rejection. The only difference observed was in the mitral half-pressure time which was much shorter in cases of rejection. However, after drawing a ROC graph, the accuracy of this parameter was insufficient for diagnosing rejection irrespective of the threshold of variation considered (23% sensitivity for a 20% shortening and 36% sensitivity for a 10% shortening). The authors conclude that Doppler echocardiographic study of left ventricular filling is of limited value for the diagnosis of acute minimal or moderate rejection in cardiac transplant patients. The half-pressure time may be a useful complement to endomyocardial biopsy or when biopsy investigations are performed less frequently.

Regional blood flow in microgravity: adaptation and deconditioning.

The objectives were to evaluate cardiac and peripheral changes induced by microgravity with and without countermeasures (CM), to assess the peripheral response to orthostatic tests (tilt, LBNP). Inflight or HDT, we used echography and Doppler to assess the left heart function and the peripheral arteries. We studied the cardiovascular system during 1) 21-d and 25-d spaceflights without CM, 2) 14.d spaceflight with "bracelets" CM, 3) 28-d HDT with and without LBNP, and 4) 30-d HDT with and without Exercise+LBNP. Similar peripheral circulation changes were noticed in both astronauts and HDT subjects without CM. There was a decrease in renal, cerebral, and femoral vascular resistances and maintenance of cerebral flow at rest, and a lack of increase in lower limb vascular resistance and abnormal flow redistribution during orthostatic tests. Conversely, with CM at rest, cerebral and renal vascular resistances stayed elevated and femoral resistance decreased, but less than without countermeasures. Lower limb vascular resistance increased normally, peripheral flows were adequately redistributed during orthostatic tests, and no orthostatic intolerance was observed. This confirms the efficiency of countermeasures (LBNP, exercise, cuffs) in preserving the vasomotor tone in most peripheral areas at rest and reducing the development of orthostatic intolerance.

[Transesophageal echography and systemic ischemic incidences: 235 cases]. / Echographie transoesophagienne et accident ischémique systémique: 235 cas.

From the first of June 90 to the thirty first of January 94, transesophageal echocardiography was performed in 235 consecutive patients (mean age 56+/-16 years), presenting either with cerebral ischemic event (n = 202) or a peripheral arterial embolism (n = 33). All patients had normal echocardiographic and Doppler examinations of the carotid arteries, and transthoracic echocardiography did not show any possible cardiac origin for stroke. Ninety seven patients (41.2%) had documented cardiac disease and/or atrial fibrillation (group 1); 138 patients (58.8%) had no previous cardiovascular history (group 2). Transesophageal echocardiography revealed a possible embolic source in 65.9% of cases (group 1) compared with 29.7% of cases in group 2 (p < 0.001). Intracavitary thrombus and spontaneous contrast in the left atrium were detected only in group 1 (21.6% vs 0%, p < 0.001 and 24.7% vs 0%, p < 0.001 respectively). Patent foramen ovale was more frequent in group 2: 14.5% of cases vs 4.1% of cases, p < 0.01. There was no significant difference between atheromatous aortic plaques and interatrial septam aneurysm incidence in the two groups. Patent foramen ovale and interatrial septal aneurysm were more frequent in group 2: 85% of cases vs 10% of cases in group 1. Transesophageal echocardiography contributes more in patients with a history of cardiac disease. In patients without cardiac disease, patient with foramen ovale and interatrial septal aneurysm were mainly detected: their association represented a risk factor of cerebral ischemic event. Therefore transesophageal echocardiography should be performed in young patients or in case of recurrent event.

Influence of the thigh cuffs countermeasure on the cardiovascular adaptation to 0.g (14 and 21 day Mir spaceflights).

Assess the 0.g induced cardiac and vascular changes at rest on two cosmonauts: one using thigh cuffs from flight day 1 to 8 (Mir 14d flight) the second one not using thigh cuffs (Mir 21d flight). Both were not using intensively any other countermeasure. The ultrasound device onboard Mir with Echo, Doppler, and TM, modes was used.