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.

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.

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.

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.

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.

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.

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.

The contribution of nuclear medicine and ultrasounds in cardiac surgery.

The constant progress in surgical techniques during the last few years have prepared the way for important developments in the field of noninvasive cardiac exploration. Their non-traumatic character, appreciable in diagnostic and preoperative examinations, become indipensable whenever there is a need to repeat the examination in order to evaluate the effects of a treatment or to monitor progress both in the short and long term. In order that such methods be adopted in cardiac surgery it is important that not only must they be without risk but also that the results obtained be clearly presented, if possible in the form of images, and allow a quantitative interpretation. It is necessary also that the results can be justified both by clinical experience and also by comparison with other examinations. No procedure, not even radiologic, can at the same time explore the myocardium and its perfusion, the central circulation and the cardiac haemodynamics. By reason of their respective principles, radioisotopic methods and ultrasounds tackle cardiac problems in different ways and facilitate, by appropriate choice of methods, the selection of one diagnostic response from among several. This paper contains first of all, a resume of the principal nuclear and ultrasonic techniques used together with their basic principles. Next we try to show how these non-invasive techniques, most with dynamic imaging, can assist cardiac surgery. For this, we successively look at the different pathologies, working from the exterior (pericardium) towards the interior (intracardiac structures and central circulation) and covering the different aspects of the myocardial pathology. In each case the mutual contributions of physical techniques is specified as well as the preference for either isotopic or ultrasonic methods.

[Angiography of right ventricular volume after surgical repair of tetralogy of Fallot]. / Etude angiographique des volumes du ventricule droit après correction chirurgicale de la tétralogie de Fallot.

Right ventricular volume and ejection fraction were measured in children who had undergone surgical repair for tetralogy of Fallot with excellent results. Fourteen children who had been operated upon at the age of 3 +/- 2.6 years had cardiac catheterization and cineangiography of the right ventricle at the age of 4.6 +/- 2.7 years. Right ventricular volumes were determined from single-plane cineangiography in right anterior oblique projection (Ferlinz method). Eleven children with a normal right ventricle served as controls. Dual projection cineangiography of the pulmonary artery enabled the pulmonary insufficiency to be divided into 4 grades. Echocardiography with colour-coded doppler velocimetry was also performed, showing the absence of residual shunt and of tricuspid, mitral and aortic valve abnormalities. The extension of pulmonary regurgitation flow to the right ventricle was analysed and divided into 4 grades. Pulmonary insufficiency was present in all patients; it was graded 1 or 2 by the two methods in 8 cases (group A) and 3 or 4 by one or the other of the two methods in 6 cases (group B). In 7 patients of group A the operation had included the insertion of a small patch to widen the pulmonary channels (infundibulum alone in 3 cases, transvalvular in 4 cases); in 5 patients of group B a large infundibulo-pulmonary transvalvular patch had been installed. The right ventricular systolic pressure was always below 50 mmHg (mean: 40.9 +/- 6.7 mmHg) and the systolic gradient between right ventricle and pulmonary artery never exceeded 30 mmHg (mean: 14.9 +/- 6.2 mmHg).(ABSTRACT TRUNCATED AT 250 WORDS)

[Contribution of two-dimensional echography in predicting spontaneous closure of interventricular defects in infants]. / Apport de l'échographie bidimensionnelle dans la prédiction de fermeture spontanée des communications interventriculaires du nourrisson.

The aim of this study was to assess the evolution of ventricular septal defects (VSD) with respect to their initial echocardiographic appearances: size and site. One hundred consecutive neonates under 3 months of age with a typical VSD murmur, were included in a prospective study. Malformation syndromes and associated cardiac disease were criteria of exclusion. Disappearance of the murmur was indicative of closure of the VSD. The VSDs were classified as: small (diameter less than or equal to 3 mm), medium (3 to 6 mm) and large (greater than 6 mm). Twelve children were lost to follow-up; the remainder were followed up for an average of 35 months. The VSDs were muscular (39%), membranous (37%), infundibular (2%) or unlocalised (22%). Of the muscular VSDs, 85% were small and 15% were medium-sized; 48% of membranous VSDs were small, 43% were medium and 9% large-sized. Spontaneous closure was observed in 64% of cases but this figure varied with the size and site of the VSD. The prognosis of unlocalised VSDs was excellent (100% spontaneous closures at 1 year), as was that of small muscular VSDs (89% spontaneous closures at 1 year). The prognosis of medium size muscular and small membranous VSDs was less favourable: 40% closures at 1 year, 50% closures at 2 years respectively. The closure of medium-sized membranous VSDs was slower: 7% at 2 years. It was essentially in this group and that of large-sized membranous VSDs that the surgical indications were mostly to be found. No spontaneous closures were observed in the large membranous or the infundibular VSDs.