CD34+ progenitor cell transplantation from two HLA-mismatched healthy fathers to two infants with severe aplastic anemia

Pluripotent stem cells of hematopoiesis are included among CD34+ cells in the blood and bone marrow. After granulocyte-colony stimulating factor (G-CSF) mobilization, 1-2% of the mononuclear cells in the blood are CD34+ cells, which can be obtained by leukapheresis. We performed CD34+ progenitor cell transplantation in two children with severe aplastic anemia (SAA) who lacked HLA-matched donors. The donors were treated with G-CSF, 600 micrograms/body/day subcutaneously, for 4-5 days. CD34+ cell selection was performed from the apheresis concentrate with mouse anti-CD34 antibody 9C5 and magnet beads coated with sheep anti-mouse IgG1. After the transplantation, the patients received tacrolimus to prevent graft-versus-host disease (GVHD). G-CSF was given to both patients. A mean number of 4.96 x 10(6) CD34+ cells per kilogram of body weight were transplanted. The hematopoietic recovery after the CD34+ cell transplantation was rapid, except for platelets, and acute GVHD was less than or equal to grade I. Case 1, who demonstrated mixed chimerism, anemia and thrombocytopenia after the graft, received a second transplant with intensified preconditioning, and now sustains complete and stable hematopoiesis after a follow-up of 314 days posttransplant. Although Case 2 showed early rejection and received a second transplant, sustained engraftment was never achieved. However, the patient's own hematopoiesis appeared. For SAA patients who do not have HLA-matched donors, this type of approach seems to be a feasible and useful method. However, an intensified preconditioning regimen to overcome the high likelihood of rejection should be employed.

Changes in hemostatic parameters in hepatic veno-occlusive disease following bone marrow transplantation

Hepatic veno-occlusive disease (VOD) is a major complication after bone marrow transplantation (BMT). Its prediction, diagnosis and treatment remain unclear. Examination was made of changes in hemostatic parameters in patients with or without VOD after BMT. Twenty-seven children were studied following BMT. Eight of them developed VOD. Tissue plasminogen activator (t-PA), plasminogen activator inhibitor 1 (PAI-1), thrombomodulin (TM), von Willebrand factor (vWF), factor VII, fibrinogen (FBG), FDP, D-dimer (D-D), plasminogen (PLG), thrombin-antithrombin III (TAT), alpha 2-plasmin inhibitor/plasmin complex (PIC), antithrombin III (AT-III), protein C, N-terminal propeptide for type III procollagen (P-III-P), were measured weekly from pre-BMT to day 28 after BMT. In VOD patients, t-PA and PAI-1 significantly increased (P < 0.05) and FBG significantly fell during the post-transplant period (P < 0.05). Significantly low AT-III and PLG were also noted before VOD (P < 0.05). There were no changes in other hemostatic parameters. t-PA, PAI-1 and FBG would thus appear useful markers for the diagnosis of VOD, and AT-III and PLG, predictive markers for VOD. The coagulation-fibrinolysis system following endothelial cell damage may contribute to the onset of VOD.

Wada memory and timing of stimulus presentation

We compared Wada memory performance for stimuli presented at two timing intervals following amobarbital injection in 47 non-lesional patients with complex partial seizures (L = 26; R = 21). A significant interaction between seizure focus and timing of presentation was present (P < 0.03). Memory performance for objects whose presentation began approximately 50-55 s following amobarbital administration differed as a function of ipsilateral vs. contralateral injection at a very high level of statistical significance (P < 0.00001). Items presented approximately 4 min, 30 s post injection were also related to seizure onset literality, but at a lower statistical level (P < 0.01). Presentation of Wada memory stimuli earlier during hemispheric anaesthesia yields results that are more sensitive to lateralized temporal lobe seizure onset than does presentation of items later during the procedure.

[The clinical significance of minimal residual disease of acute leukemia with t(4;11) (q21;q23)]

Hybrid fusion genes are specific tumor markers of several leukemic subtypes. The use of reverse transcription-polymerase chain reaction (RT-PCR) to amplify chimeric cDNAs allows sensitive detection of the leukemia clone. The clinical relevance of minimal residual disease (MRD) remains controversial. In this report, an infantile acute lymphoblastic leukemia with t(4;11) (q21; q23) was analyzed after each treatment for the presence of MRD by RT-PCR amplification of the MLL/LTG4 fusion gene which became available recently. The patient soon achieved a hematological CR, after induction therapy, and underwent autologous BMT following consolidation chemotherapy for 9 months. However, he relapsed three months after the BMT. MRD was always detectable during his clinical course. These findings suggest that the detection of MRD of the MLL/LTG4 fusion transcript is a useful tool for monitoring MRD and selecting treatment.

The significance of ictal depth EEG patterns in patients with temporal lobe epilepsy

We reviewed 187 depth recorded seizures in 33 patients with non-lesional temporal lobe complex partial seizures. All patients had a minimum of 1 year follow-up following temporal lobectomy. We classified seizure onset pattern as rhythmic activity, attenuation, or repetitive spikes or spike wave complexes. The most common pattern of seizure onset was rhythmic activity and the next most common pattern was repetitive spikes. Seventy-five seizures (49%) had only one seizure onset pattern, and 79 seizures (51%) had a combination of seizure onset patterns. The degree of hippocampal gliosis strongly predicted the type of seizure onset pattern (Chi square = 24.07, 2 d.f., P < 0.01). The rhythmic activity pattern was associated with mild gliosis, and the repetitive spike pattern was associated with severe gliosis. We classified seizure onset as focal or regional based on the number of electrode contacts that were involved by the ictal EEG. A focal seizure onset was associated with an excellent outcome following temporal lobectomy.

Structural instability of a transgene locus in tobacco is associated with aneuploidy

This paper describes molecular and cytogenetic evidence for the stability of a transgene locus that is present on the triplicated chromosome in an aneuploid tobacco line. This instability was manifested in several ways in trisomics including a major chromosome rearrangement that was detectable cytogenetically, smaller scale DNA rearrangements that occurred both germinally and somatically, and methylation/epigenetic silencing. In a deletion derivative of the locus, DNA breakpoints were found in AT-rich regions. One of these regions binds to nuclear scaffolds in vitro, suggesting a possible role for aberrant topoisomerase II cleavage in destabilization of the locus. The implications of increased chromosome instability in aneuploids for plant karyotype evolution and human carcinogenesis are discussed.

Changes of plasma atrial and brain natriuretic peptide levels during hemodialysis

OBJECTIVES

The purpose of this study was to evaluate the effect of hemodialysis on the plasma concentration of atrial and brain natriuretic peptides, and to determine the two-dimensional echocardiographic parameters affecting the changes of plasma atrial and brain natriuretic peptide levels in patients with chronic renal failure.

BACKGROUND

Brain natriuretic peptide has been found in human cardiac tissue and increases in patients with congestive heart failure. However, the factors that stimulate the secretion of plasma brain natriuretic peptide have not yet been fully clarified.

METHODS

In 15 patients with chronic renal failure, plasma atrial and brain natriuretic peptide levels and two-dimensional echocardiographic parameters were measured before and after each session of hemodialysis.

RESULTS

Plasma atrial natriuretic peptide levels significantly decreased from 367 +/- 537 pg/mL to 138 +/- 167 pg/mL after hemodialysis (p < 0.01). However, plasma brain natriuretic peptide levels did not significantly change after hemodialysis. Left atrial dimension significantly decreased (41.1 +/- 6.6 vs. 36.3 +/- 6.2 mm, p < 0.01) and left ventricular end-diastolic dimension slightly decreased after hemodialysis (57.0 +/- 10.3 vs. 55.7 +/- 9.9 mm, p < 0.05). The decrease of left atrial dimension was greater than that of left ventricular end-diastolic dimension (4.9 +/- 1.6 vs. 1.3 +/- 0.6 mm, p < 0.05). Plasma brain natriuretic peptide levels significantly correlated with fractional shortening both before and after hemodialysis (r = 0.65, p < 0.05).

CONCLUSION

Plasma atrial natriuretic peptide levels significantly decreased as the right and left atrial overloads decreased, and plasma brain natriuretic peptide levels did not significantly decrease after hemodialysis. Plasma brain natriuretic peptide levels were not significantly influenced by acute hemodynamic change, such as hemodialysis. However, plasma brain natriuretic peptide levels were significantly correlated with basic cardiac function.

Gene silencing mediated by promoter homology occurs at the level of transcription and results in meiotically heritable alterations in methylation and gene activity

The promoter homology-dependent inactivation of a 35Spro-hygromycin phosphotransferase (hpt) gene, which is present at the H2 locus, by the multipurpose 271 silencing locus has been studied. The 271 locus can silence any gene under the control of the 35Spro as well as endogenous nitrite reductase (NiR) genes of tobacco because of the presence of a chimeric antisense gene (35Spro-RiN). All F1 progeny of a cross between homozygous H2 and 271 lines were sensitive to hygromycin and were chlorotic (a symptom of nitrogen deficiency). These phenotypes were accompanied by a reduction in the steady-state levels of Hyg and NiR transcripts. Transcriptional run-on experiments indicated, however, that while NiR silencing occurred post-transcriptionally, the hpt gene was inactivated at the transcriptional level; this was associated with increased methylation of the 35Spro of the hpt gene. NiR gene expression recovered uniformly to wild-type levels in first generation backcross (BC1) progeny that did not inherit the 271 locus. In contrast, hygromycin resistance was only partially and non-uniformly regained among adult BC1 plants. Moreover, substantial silencing of the hpt gene could persist into the BC2 generation. Genomic sequencing demonstrated that the meiotic heritability of hpt silencing in the absence of the 271 locus was correlated with cytosine methylation primarily at CpG and CpNpG residues. Despite this residual methylation, H2 loci weakened by an association with 271 did not acquire the ability to silence a 'naive' H2 locus. Fluorescence in situ hybridization revealed that the 271 locus was located at a telomere. The results strengthen the distinction between silencing effects involving homology restricted to coding or promoter regions, respectively. The former is a post-transcriptional process that is meiotically reversible; the latter is due to transcriptional inactivation and is associated with increased promoter methylation, which can lead to meiotically heritable reductions in target gene activity. The relevance of these data for the meiotic heritability of silencing, the non-transferability of silencing activity, and the basis of 271 silencing effects is discussed.

Precision of dipole localization in a spherical volume conductor: a comparison of referential EEG, magnetoencephalography and scalp current density methods

In this study, we determined the influence of dipole orientation, dipole location, and number of recording sites on the precision of dipole localization in a spherical volume conductor. We compared localization from referential EEG (R-EEG), scalp current density EEG (SCD-EEG) and magnetoencephalography (MEG). Dipole orientation had a small influence on the precision of dipole localization for R-EEG and SCD-EEG. Dipole location relative to the recording sites, dipole depth, and number of recording channels strongly influenced the precision of dipole localization. Assuming equal signal to noise conditions for each recording method, MEG and SCD-EEG had a similar precision for dipole localization of a single tangential dipole source and both methods were more precise than R-EEG. However, SCD-EEG was inferior to MEG for distinguishing a single tangential current source from a pair of deeper radial current sources. In summary, these results suggest that the MEG will be most useful for localization of multiple simultaneous dipole sources.

Wada memory asymmetries predict verbal memory decline after anterior temporal lobectomy

We examined Wada memory and neuropsychological memory function in 34 nonlesional patients who underwent anterior temporal lobectomy (ATL) and who were seizure free at 1-year follow-up. Patients who displayed a decline on verbal memory measures that exceeded 1 SD after left ATL had significantly smaller left/right Wada memory asymmetries than left ATL patients without a significant verbal memory decline. When Wada memory asymmetries were used to predict verbal memory decline after left ATL in individual patients, similar statistically significant effects were present. No significant relationship between Wada memory and postoperative memory was present in right ATL patients, and postoperative memory function was not related to Wada memory performance after either left hemisphere or right hemisphere injection alone. We conclude that Wada memory asymmetries provide one measure of the risk to material-specific decline in verbal memory after left ATL.

Seizures associated with stroke in childhood

Seventy-three consecutive children younger than 17 years of age seen from 1978 to 1992 with acute hemiplegia from stroke, were retrospectively reviewed to evaluate the incidence of seizures and the risks of recurrent seizures after stroke. The population consisted of 56 children with cerebral infarction, 12 with intracranial hemorrhage, and 5 with transient ischemic attack. Children whose strokes occurred in the neonatal period and those secondary to trauma, malignancy, or infection were excluded. Mean follow-up time was 43.5 months (range: 12-156 months). At least 1 seizure occurred in 36 patients (49.3%) and recurrent seizures occurred in 21 patients (28.8%). Recurrent seizures developed more often among patients who had initial seizures with delayed onset (P < .05). In 56 patients with cerebral infarction, 16 of 31 patients (51.6%) with cortical involvement documented by neuroradiologic studies and 1 of 25 patients (4%) without cortical involvement developed recurrent seizures (P < .01). In 12 patients with intracranial hemorrhage, 3 of 10 patients with cortical involvement and none of 2 patients without cortical involvement developed recurrent seizures. It is concluded that seizures commonly occur in childhood stroke. Risk factors for recurrent seizures include later onset of initial seizures and presence of cortical involvement.

Multichannel magnetoencephalography in ablative seizure surgery outside the anteromesial temporal lobe

Magnetoencephalography (MEG) was used to evaluate 40 candidates for seizure surgery thought to have foci outside the anteromesial temporal lobe. Of 29 cases with electrographic data suggesting a convexity focus, MEG spikes were recorded from 28. In 21, MEG and electrographic data were localized to the same area. Invasive studies were, or could have been, avoided in 13 cases based on MEG and other noninvasive data. MEG was not localizing value in 4 orbitofrontal or 7-depth-nonlocalized cases. Seventeen patients with MEG epileptiform data have had postoperative follow-up. Eight of 13 with electrographic and MEG data localized to the same area are seizure free. None of 4 with spatial discordance of MEG electrographic data are seizure free.

Inheritance and expression of a transgene insert in an aneuploid tobacco line

A T-DNA locus comprising nptII, uidA and nos genes--all under the control of the nos promoter (this locus was designated K because it encodes resistance to Kanamycin)--was found to be inherited erratically in a transgenic tobacco line. This anomalous behavior was partially explained following a karyotype analysis of plants representing several generations: these plants were aneuploids, presumably for the K-containing chromosome. During four generations of sexual propagation, transgenic plants that were either trisomic or tetrasomic for the K-containing chromosome (i.e. 2n = 49 or 2n = 50, respectively) were obtained. The trisomic plants (2n = 48 + 1) were virtually indistinguishable phenotypically from normal euploids (2n = 4x = 48), whereas the tetrasomic plants (2n = 48 + 2) were smaller, had somewhat misshapen leaves and exhibited reduced fertility. Although the amount of NPTII protein in different trisomic (K--, KK-, KKK) and tetrasomic (KK--, KKK-) plants was generally consistent with a K dosage effect, the genetic behavior of each trisomic--with respect to segregation of KanR and marker gene activity in progeny--was unique and not completely explicable by invoking aneuploidy. Specifically, unexpected gains or losses of K could occur, suggesting the formation of double reductional gametes and/or frequent gene conversion at this locus. The susceptibility of K locus marker genes to trans-inactivation in the trisomic and tetrasomic lines was tested by crossing in partially homologous silencing loci. In all transgenotypes tested, the three K marker genes were sensitive to trans-silencing, which was accompanied by methylation in all copies of the nos promotor. In addition to this directed inactivation/methylation, the K locus could also undergo infrequent, spontaneous partial methylation, which produced stable epialleles. In most plants, however, the multiple copies of the nos promoter at this locus remained unmethylated and active through four generations in all transgenotypes examined. The significance of these results for irregular inheritance patterns, aneuploid syndromes and homology-dependent gene silencing is discussed.

Differential effects of chronic antidepressant treatment on 5-HT1C receptor binding sites in Wistar rat brain

The effects of chronic clomipramine, imipramine and clorgyline on 5-HT1C receptors were studied in discrete brain regions, in male Wistar rats, using [3H]mesulergine to label the receptor binding sites. Clorgyline treatment significantly reduced [3H]mesulergine binding (Bmax values) in both the hypothalamus and striatum compared to saline-treated animals. There were no differences in the maximum number of [3H]mesulergine binding sites following clorgyline in the hippocampus, frontal cortex or brainstem. Neither clomipramine or imipramine treatment resulted in any significant changes in 5-HT1C receptor number in the brain regions examined here. Furthermore, the Kd values (receptor affinity) for [3H]mesulergine binding were not significantly different comparing treatment groups to control animals. The significant changes in discrete brain regions following chlorgyline treatment suggest that 5-HT1C receptors may be involved in the clinical efficacy for the treatment of depression and other neuropsychiatric disorders.

Homology-dependent gene silencing in transgenic plants: epistatic silencing loci contain multiple copies of methylated transgenes

Previous work has shown that two homologous, unlinked transgene loci can interact in plant nuclei, leading to non-reciprocal trans-inactivation and methylation of genes at one locus. Here, we report the structure and methylation of different transgene loci that contain the same construct but are variably able to inactivate and methylate a partially homologous, unlinked target locus. Silencing loci comprised multiple, methylated copies of the transgene construct, whereas a non-silencing locus contained a single, unmethylated copy. The correspondence between strength of silencing activity and copy number/degree of methylation was further demonstrated by producing novel alleles of a strong silencing locus: reducing the transgene copy number and methylation within this silencing locus decreased its ability to inactivate the target locus. The strong silencing locus, which was located close to a telomere, trans-inactivated various structural variants of the original target construct, regardless of their location in the genome. This suggests that the silencing locus can scan the entire genome for homologous regions, a process possibly aided by its telomeric location. Our data support the idea that epistatic trans-inactivation of unlinked, homologous transgenes in plants results from a pre-existing epigenetic difference between transgene loci, which is subsequently equalized by "epigene conversion" involving DNA-DNA pairing.

Susceptibility of transgene loci to homology-dependent gene silencing

Previous work has shown that two unlinked, partially homologous transgene loci can interact in plant nuclei, leading to reversible methylation and inactivation of one transgene locus in the presence of the second. To study whether the chromosomal location of a transgene influences its susceptibility to trans-inactivation, we retransformed four transgenic lines, which contained the same construct (H) integrated in different chromosomal locations, with a second, partially homologous construct (K). At least 50 double transformants (DTs) were regenerated from each single transformants (ST) and screened for inactivation of markers [chloramphenicol acetyltransferase (CAT); hygromycin resistance (HYGR)] at the resident H locus. For two STs, H locus markers were inactivated in less than 1% of the DTs, suggesting that, at these integration sites, H was relatively resistant to trans-inactivation. In contrast, the other two STs appeared to be more sensitive to trans-inactivation: 4-10% of the DTs were CAT- and/or Hygs. Inactivation of H locus markers could be attributed to two distinct phenomena: 1. Regeneration from cells containing different epigenetic states of H, in which either both, one or none of the H alleles was active. This instability in the expression of the H locus, which was independent of K, was more pronounced in the homozygous state, and was associated with cellular mosaicism of expression and methylation. 2. The presence of an unlinked K locus could weaken the HygR phenotype by transcriptional inactivation and increased methylation of the hph gene at the H locus. These results indicated that a susceptible transgene locus is inherently unstable and partially methylated, and that these characteristics are exacerbated when the locus is homozygous for the transgene and/or when an unlinked homologous transgene is present.

Focal cerebral metabolic abnormality in a patient with continuous spike waves during slow-wave sleep

We report an 11-year-old boy with continuous spike-wave discharges during sleep accompanied by partial motor and atypical absence seizures, psychomotor regression, and severe behavior problems. During wakefulness, epileptiform discharges occurred over the right parietal region, suggesting that the continuous spike-wave discharges during sleep were a manifestation of secondary bilateral synchrony. Bilateral suppression of the spike-and-wave activity was observed after right-sided intracarotid amobarbital injection, further supporting the impression of secondary bilateral synchrony. The right superior temporoparietal increase in metabolic activity during continuous spike-wave discharges and noncontinuous spike-wave discharges was seen on [18F]fluorodeoxyglucose positron emission tomography and supports a right temporoparietal focus in our case. The presence of a focal abnormality suggests that surgical therapy may be effective.

Use of scalp-sphenoidal EEG for seizure localization in temporal lobe epilepsy

We determined the accuracy and sensitivity of scalp-sphenoidal EEG for seizure focus localization in 50 patients who became seizure-free or had rare seizures following temporal lobectomy. EEG localization was based on concordant interpretations of scalp-sphenoidal ictal EEG by three independent interpreters. All patients became seizure-free or had rare seizures following temporal lobectomy. Localization from EEG disagreed with the side of surgery in only 1 (2%) of 50 patients. We identified 3 distinct patient groups with a low, moderate, and high likelihood of having a focal ictal EEG pattern during a seizure. These groups comprised 31% (low likelihood), 44% (moderate likelihood), and 25% (high likelihood) of patients. A model based on these results suggests that with multiple ictal EEG recordings, accurate localization from scalp-sphenoidal EEG is possible in approximately up to 65-70% of patients with temporal lobe epilepsy.

Seizure localization in temporal lobe epilepsy: a comparison of scalp-sphenoidal EEG and volumetric MRI

We determined the accuracy of volumetric MRI (based on identification of unilateral hippocampal atrophy) and scalp-sphenoidal EEG (based on concordant interpretations of scalp-sphenoidal ictal EEG by three independent interpreters) for seizure focus localization in 20 patients with temporal lobe epilepsy. All patients became seizure-free or had rare seizures following temporal lobectomy. Among the 20 patients, nine (45%) met both MRI and EEG localization criteria, six (30%) met MRI localization criteria alone, three (15%) met EEG localization criteria alone, and two patients (10%) did not meet either localization criteria. In the 18 patients meeting MRI or EEG localization criteria, the predicted localization agreed with the side of temporal lobectomy. These results suggest that a noninvasive approach combining MRI and EEG will correctly localize the side of seizure onset in most patients with temporal lobe epilepsy.

Analysis of the 5-HT1C receptor and the serotonin uptake site in fawn-hooded rat brain

Both the 5-HT1C receptor and the 5-HT uptake binding sites were measured in Fawn-Hooded, Sprague-Dawley and Wistar rats. Five brain regions were examined: frontal cortex, hippocampus, striatum, hypothalamus, and brainstem. We found significant differences in the Bmax and Kd values in various brain regions comparing Fawn-Hooded rats, with Sprague-Dawley and Wistar animals. The regional differences in receptor number and affinity in both the 5-HT1C receptor and the 5-HT uptake site in the Fawn-Hooded strain, relative to Wistar and Sprague-Dawley animals, provide support for the use of the Fawn-Hooded rat in serotonin dysfunction studies.

Regional analysis of 5-HT1A receptors in two species of Peromyscus

Two species of deer-mice, Peromyscus maniculatus (P. man) and Peromyscus leucopus (P. leu), were compared for differences in 5-hydroxytryptamine1A (5-HT1A) receptor number and affinity. Both species enter into torpor; however, P. man enters spontaneous torpor with a higher frequency and for a longer duration than P. leu. Further, compared to P. leu a higher percentage of P. man exhibit daily torpor. Deer mice can be induced to enter torpor by a reduction in food supply, shortened photoperiods, and decreasing ambient temperature. Under these conditions, P. man enters into torpor more frequently, for longer durations, and with a higher percentage of individuals as compared to P. leu. [3H]8-OH-DPAT was used to label 5-HT1A brain receptors in three brain regions: the frontal cortex, brainstem, and striatum. In addition, the hypothalamus and hippocampus were examined for 5-HT1A receptor differences; however, no measurable specific binding could be determined in these regions. In the frontal cortex, the Bmax values were significantly lower in P. man compared to P. leu. There were no significant differences in the Bmax values in the striatum and brainstem between P. man and P. leu. Further, there were no significant differences in the Kd values between the two species in any of the brain regions examined. The absence of any difference in receptor number or affinity in any of the brain regions examined, except the cortex, suggests that the 5-HT1A receptor is most likely not involved in a more efficient pathway to torpor.

Localization of temporal lobe seizures with quantitative EEG

In this study, we describe a quantitative EEG method for localization of seizure onset in 29 patients with temporal lobe epilepsy. We used right-left differences in relative power and a logistic regression to predict the side of seizure onset. The optimum bipolar channels were T4-T6/T3-T5 and the optimum frequency band was 4-10.5 Hz. Using a threshold probability of 0.75 for classification, the best quantitative EEG method classified 23 patients (79%) correctly, 2 patients (7%) incorrectly, and 4 patients (14%) as undetermined localization. In comparison, 3 electroencephalographers visually interpreted these same EEGs and classified 20-25 patients (69-86%) correctly, 1 patient (3%) incorrectly and 3-8 patients (10-28%) as undetermined localization. In the 8 patients classified as undetermined localization by at least one interpreter, the quantitative EEG method classified 5 patients correctly, 1 patient incorrectly and 2 patients as undetermined localization. These results suggest that quantitative EEG might improve the reliability of ictal EEG localization and potentially reduce the need for invasive intracranial EEG monitoring.

Regional analysis of 5-HT1A and 5-HT2 receptors in the fawn-hooded rat

The Fawn-Hooded strain of rats exhibits a hemorrhagic disorder, known as platelet storage pool deficiency. In addition to the platelet dysfunction, there is an altered response to certain serotonin drugs. To assess the characteristics of the binding to 5-HT1A and 5-HT2 receptors in this strain, regions of the brain from Fawn-Hooded, Sprague-Dawley and Wistar male rats were examined. The drug [3H]8-OH-DPAT was used to label 5-HT1A receptors and the Kd values for frontal cortex, hippocampus, striatum, hypothalamus and brainstem were similar in all three strains of rat. As with the 5-HT1A receptors, no differences were observed in the Kd values for 5-HT2 receptors, in any of the regions examined, among the three strains. However, the Bmax for the binding of [3H]8-OH-DPAT in the striatum and brainstem of Fawn-Hooded rats was less than in the Sprague-Dawley and Wistar animals. Furthermore, 5-HT2 receptors displayed a greater Bmax value in the striatum and in the frontal cortex of Fawn-Hooded animals, compared to Sprague-Dawley and Wistar rats. These differences in receptors are consistent with previous studies in which Fawn-Hooded rats were found to have altered serotonergic function, relative to Wistar and Sprague-Dawley animals.

Experimental tests of a simple diffusion model for the estimation of scattering and absorption coefficients of turbid media from time-resolved diffuse reflectance measurements

When a picosecond light pulse is incident upon a turbid medium such as tissue, the temporal distribution of diffusely reflected and transmitted photons depends on the optical absorption and scattering properties of the medium. From diffusion theory it is possible to derive analytic expressions for the pulse shape in terms of the optical interaction coefficients of a homogeneous semi-infinite medium. Experimental tests of this simple model in tissue-simulating liquid phantoms of different geometries are presented here. The results of these tests show that, in a semi-infinite phantom, the application of the diffusion model provides estimates of the absorption and transport-scattering coefficients that are accurate to better than 10%. Comparable accuracy was also obtained with this simple model for finite slab, cylindrical, and spherical volumes as long as the objects were of sufficient size. For smaller volumes the absorption coefficient was overestimated because of the significant loss of photons at the bounda ries of the object.

The gap between mitral leaflets as a cause of mitral regurgitation: relationship to mitral valve prolapse

The gap between the tips of the anterior and posterior mitral leaflets was studied to assess the significance of this gap in the diagnosis of mitral valve prolapse. The subjects were 39 patients in whom the gap was seen and the mitral valve did not exceed the mitral annular line in systole on two-dimensional echocardiography. Forty eight healthy subjects, in whom phonocardiography disclosed no abnormalities, served as controls. The site of the gap as well as the site and severity of mitral regurgitation were assessed with two-dimensional echocardiography and Doppler flow imaging. The incidence of mitral regurgitation was 82%, which was comparable to that in the controls (67%). The site of the gap was consistent with that of regurgitation. The gap was also seen in a low percentage of healthy subjects, but clinically significant mitral regurgitation did not accompany the gap in healthy subjects including the gap-carrying controls. On the other hand, many of the gap-carrying patients showed clinically significant mitral regurgitation. Also the fact that a gap between the tip of the anterior and posterior mitral leaflets was found to be frequently accompanied by phonocardiographical features corresponding to mitral valve prolapse indicates that the presence of a gap is a significant finding.

Stroke in pediatric acquired immunodeficiency syndrome

In a 4 1/2-year period, 4 of 68 children in a longitudinal study of neurological complications of human immunodeficiency virus (HIV) infection had clinical and/or neuroradiological evidence of stroke, yielding a clinical incidence of stroke in this population of 1.3% per year. During this period, 32 subjects died, and permission for autopsy was granted in 18 of the patients, including 3 of 4 who had clinical evidence of stroke. The prevalence of cerebrovascular pathological features in our consecutive autopsy series was higher than the clinical incidence. At autopsy cerebrovascular disease was documented in 6 (24%) of 25 children with HIV infection, including all 3 children who had clinical evidence of stroke. Four patients had intracerebral hemorrhages, 6 patients had nonhemorrhagic infarcts, and 3 had both. Hemorrhage was catastrophic in 1 child and clinically silent in 3 children, all of whom had immune thrombocytopenia. One child had an arteriopathy that affected meningocerebral arteries. In another child, the arteries of the circle of Willis were aneurysmally dilated. Two children had coexisting cardiomyopathy and subacute necrotizing encephalomyelopathy with vascular proliferation. These results suggest that stroke should be considered when children with HIV infection develop focal neurological signs.

Predisposing factors of recurrent embolization in cardiogenic cerebral embolism

To elucidate the pathophysiology of intracardiac thrombus formation, serial two-dimensional echocardiographic examinations were performed on 30 consecutive patients with acute cardiogenic cerebral embolism in parallel with measurement of hematocrit and plasma levels of antithrombin III. The data from groups of patients with and without newly formed or enlarged thrombi were compared. Intracardiac thrombi were detected in eight of the 30 patients (27%), four at admission and four after admission. Enlargement of the thrombus was observed in four, and systemic embolization recurred in three of the eight. Antithrombin III levels already were low at admission in patients who later developed thrombi or had enlarged thrombi on serial examinations. When the development or enlargement of an intracardiac thrombus was detected by echocardiography, the diameter of the inferior vena cava was found to be reduced. At the same time, a decrease in antithrombin III and an increase in hematocrit were demonstrated. Intracardiac thrombi are frequently detected by repeated echocardiographic examination in patients with cerebral embolism. Dehydration seems to accelerate thrombus formation that is reflected by a decrease in antithrombin III. A low antithrombin III level at admission and/or a decrease in antithrombin III after admission may indicate the possible recurrence of embolism.

Assessment of relationship between the pattern of hypertrophy and the function of left ventricle in patients with chronic aortic regurgitation

Pre- and postoperative echocardiograms of 64 patients with chronic aortic regurgitation who had undergone isolated aortic valvular replacement (AVR) were studied. These patients were divided into 3 groups as follows: (1) Group A patients who had preoperative end-diastolic radius to wall thickness ratio (R/Thd) less than or equal to 3. (2) Group B1 patients who had preoperative R/Thd greater than 3 and end-systolic radius to wall thickness ratio (R/Ths) less than 2. (3) Group B2 patients who had preoperative R/Thd greater than 3 and R/Ths greater than or equal to 2. Using this classification we assessed the relation between the pattern of hypertrophy and left ventricular (LV) function and the reversibility of LV dysfunction following AVR. Preoperatively, ejection fraction (EF) during handgrip exercise was unchanged in Group A (% delta EF: -2.8 +/- 7.1%) and significantly decreased in Groups B1 (-17.0 +/- 5.8%) and B2 (-20.2 +/- 4.6%). In the late postoperative period, however, it was, -1.2 +/- 3.3%, -2.0 +/- 4.6%, and -17.7 +/- 8.6% in Groups A, B1, B2, respectively. Preoperatively the slope of end-systolic wall stress/volume (ESWS-ESV relation was 1.96 +/- 0.43 in Group A (p less than 0.01 vs Group B2, NS vs Group B1), 1.54 +/- 0.38 in Group B1 (NS vs Group B2) and 1.17 +/- 0.47 in Group B2. It was stressed that a good relationship existed between the pattern of hypertrophy and function as well as the reversibility of LV dysfunction following AVR.

[Evaluation of the contractile state of the left ventricle before and after aortic valve replacement from end-systolic stress-volume relations in patients with chronic aortic regurgitation]

Before and one month after aortic valve replacement, the contractile state of the left ventricles in 10 patients with chronic aortic regurgitation were studied. The slope and intercept of the end-systolic stress-volume relationship (ESSVR) determined by M-mode echocardiography during intravenous infusion of Nitroprusside were used as an index of myocardial contractility. We found that the end-systolic wall stress-volume relationship from more than four points of pressure and dimension data have shown the linear relation for each subject with linear coefficients ranging from 0.848-0.997. There was no significant change in the slope of ESSVR between the pre- and early postoperative studies (1.66 +/- 0.37 to 1.92 +/- 1.02; p greater than 0.05), however, the intercept decreased significantly (44.7 +/- 32.4 to 29.4 +/- 28.0; p less than 0.01), which meant the leftward shift of the line of ESSVR and may imply the improvement of myocardial contractility. On the contrary, the fractional shortening decreased significantly (25.6 +/- 8.5 to 18.9 +/- 8.8%; p less than 0.01), reflecting marked reduction in preload or left ventricular end-diastolic volume (7.52 +/- 1.07 to 6.04 +/- 1.38; p less than 0.01). The change in the slope of the liner of ESSVR demonstrated that myocardial contractility might not be depressed at this time but rather improving.

A study of infantile motor neuron disease with neurofilament and ubiquitin immunocytochemistry

We report a patient with infantile motor neuron disease who had pathologic findings consistent with multisystem degeneration. Although the muscle showed denervation atrophy and spinal anterior horn cells showed either atrophy or ballooning degeneration consistent with lower motor neuron disease, the infant was hypertonic and spastic. Degenerative changes were also detected in the dorsal root ganglia, cerebellum, and thalamus. Immunohistochemical studies showed a paucity of neurofilament (NF) staining in the corticospinal tract and accumulation of phosphorylated NF in ballooned neurons. Antibodies to ubiquitin immunostained ballooned neurons in the dorsal root ganglia, anterior horns, and thalamus. Accumulation of ubiquitinated and phosphorylated NF epitopes in degenerating neurons suggest that basic abnormalities in the neuronal cytoskeleton may be instrumental in the pathogenesis of this disorder.

Immunohistochemical localization of an HIV epitope in cerebral aneurysmal arteriopathy in pediatric acquired immunodeficiency syndrome (AIDS)

A 6-year-old boy with acquired immunodeficiency syndrome (AIDS) developed aphasia and quadriplegia 3 months before his death. Cerebral vascular ectasia and multiple cerebral infarcts were noted on premortem radiological studies. Postmortem evaluation revealed diffuse aneurysmal dilatation of the circle of Willis associated with fresh and organizing thrombi, destruction of the elastic lamina, and marked intimal fibroplasia. Multiple cerebral infarcts and subacute AIDS encephalitis with basal ganglia calcification were also present. Immunohistochemistry with a monoclonal antibody (anti-gp41) to human immunodeficiency virus (HIV) demonstrated positively stained cells in the arterial wall of the circle of Willis and in the cerebral parenchyma. Double immunostaining demonstrated that gp41-positive cells in the circle of Willis were also positive for a macrophage marker or leukocyte-common antigen, but not with an endothelial marker. Some macrophages or microglia in the cerebrum were also colabeled with anti-gp41. These results suggest that HIV may be directly involved in vascular pathology associated with pediatric AIDS.

Abnormal blood pathways in left ventricular cavity in acute myocardial infarction. Experimental observations with special reference to regional wall motion abnormality and hemostasis

To elucidate the mechanism of regional hemostasis in the left ventricular (LV) cavity during myocardial infarction, the blood pathway in LV cavity was examined with contrast echocardiography injected from the left atrium before and after coronary ligation in nine canines. Before coronary ligation, contrast echoes spread over LV cavity with one rush. After ligation, smokelike echoes indicating hemostasis were observed at the apical middle of the LV cavity in five dogs with apical akinesis and at the apical area in four dogs with apical dyskinesis. The contrast echoes did not reach the apex within one diastolic period but turned upward to the outflow tract in the middle of the cavity in all dogs. In the cardiac beats that followed, some contrast echoes spread slowly toward the apex, forming a thin layer along the posterior wall in cases with akinesis but not in cases with dyskinesis. The area separated from the blood pathway developed where the smokelike echoes had been developed. Tachycardia exaggerated the abnormality of blood pathway and widened the contrast echo-free area. The abnormal pathway of the blood in apical myocardial infarction develops hemostasis in the apex. This should be one of the mechanisms of thrombus formation in myocardial infarction.

[Anterolateral papillary muscle motion before and after septal myotomy in hypertrophic obstructive cardiomyopathy]

The left ventricular outflow pressure gradient in hypertrophic cardiomyopathy results from systolic anterior motion of the mitral valve (SAM). This abnormal orientation of the valve was previously proposed to be caused by inappropriately hypertrophied papillary muscles which protrude to the interventricular septum (IVS). Septal myotomy can alter the orientation of the papillary muscles and resolve the pressure gradient, without myectomy. Recently, we have experienced two instructive cases to prove our previously advocated hypothesis. Case 1: This 54-year-old man complained of effort dyspnea, and his echocardiogram disclosed marked SAM, and a thickened IVS (28 mm) and left ventricular posterior wall (16 mm). The intraventricular pressure gradient was 134 mmHg, and there was mitral regurgitation of grade 2/4. A longitudinal incision via the aorta on the anterior portion of the IVS, toward the base of the anterolateral papillary muscle, resolved the pressure gradient and mitral regurgitation, and two-dimensional echocardiography demonstrated that the SAM resolved at the lateral aspect of the valve, but it remained on the medial side. Case 2: This 57-year-old man complained of dyspnea during effort. He had marked SAM. The intraventricular pressure gradient was 65 mmHg, and there was grade 3/4 mitral regurgitation. Longitudinal incisions on the anterior, medial and posterior parts of the IVS abolished the SAM and reduced mitral regurgitation to grade 1/4. In both cases, during systole, the anterolateral papillary muscle protruded into the left ventricular ontflow tract, causing SAM. After surgery, the direction of the muscle axis moved toward the mitral orifice during systole, resulting in alleviation of SAM on the same side of the location of septotomy. This further confirmed our concept that disoriented papillary muscles play essential roles in causing SAM. If the Venturi forces previously stressed by other investigators cause SAM, the latter should resolve on both the medial and lateral aspects, even by septotomy. Thus, the Venturi theory seems untenable.

Transient abnormal septal motion after non-surgical closure of the ductus arteriosus

Abnormal septal motion on M mode echocardiography was seen in eight of 16 patients soon after non-surgical closure of the ductus arteriosus. Ten to twenty-nine months after the procedure the abnormal septal motion had disappeared spontaneously. The cross section of the left ventricular cavity was circular both when septal motion was abnormal and when it was normal. Cross sectional echocardiography showed that there was an exaggerated anterior swinging motion of the heart in systole in patients with abnormal septal motion on the M mode recordings. The left ventricular end diastolic diameter before closure was significantly larger, and its reduction after closure was more pronounced in those with abnormal septal motion than in those without. This suggested that the abnormal septal motion was associated with relief of long standing left ventricular volume overload. It is suggested that acute shrinkage of the heart caused temporary laxity of the pericardium, and consequently more movement of the heart within the thorax. The return of normal septal motion suggests that the pericardium gradually shrank to accommodate the smaller heart.

[Papillary muscle infarction: echocardiographic features and genetic factors]

To study the pathogenesis of papillary muscle infarction, its echocardiographic features were examined in 60 patients with old inferior infarction. Sixty-three healthy elderly persons served as the controls. 1. The papillary muscles were echocardiographically classified as fingerlike and non-fingerlike in configuration whose frequencies were 43% and 57%, respectively. In healthy subjects, the papillary muscles were less echogenic than the left ventricular wall. 2. In five patients, the posteromedial papillary muscle exhibited enhanced echo intensity and no contraction. The papillary muscles in two of these five patients were histologically examined and the diagnosis of papillary muscle infarction was verified. In these five patients, the papillary muscles were echocardiographically classified as fingerlike, and left ventricular infarction was observed to involve the attachment of the posteromedial papillary muscle. All five patients had mitral valve prolapse; posterior in four and anterior in one. Inferior infarction extended to the region just beneath the mitral annulus in the former four patients, but not in the latter one. 3. The echocardiographic features of papillary muscle infarction consisted of enhanced echo intensity of the papillary muscle and mitral valve prolapse, especially that of the posterior leaflet at the posteromedial commissural side, and extension of the asynergy region to the attachment portion of the papillary muscle. The fingerlike morphology of the papillary muscle and involvement of the attachment within the infarcted region are predispositions to the development of papillary muscle infarction.(ABSTRACT TRUNCATED AT 250 WORDS)

Mechanism of mitral regurgitation in patients with myocardial infarction: a study using real-time two-dimensional Doppler flow imaging and echocardiography

The aim of the present study was to elucidate the mechanisms of mitral regurgitation accompanying myocardial infarction. Severity and site of mitral regurgitation was evaluated by the real-time two-dimensional Doppler flow imaging technique in 81 patients with old myocardial infarction. The incidence of mitral regurgitation did not depend on the region of infarction. There was, however, a close relationship between the site of regurgitation and the region of infarction. In patients with mitral regurgitation spurting from the posteromedial area of the valve, the inferior wall was involved in infarction without exception and in some of these patients, the posteromedial papillary muscle was also found to be affected by myocardial infarction; in those with regurgitation spurting from the anterolateral area, the anterior wall showed asynergy. On the other hand in patients with mitral regurgitation spurting from the central area, the region of infarction varied. In these patients, however, the larger the diameter of the mitral anulus, the more severe the grade of regurgitation. The extent of asynergy was another factor related to the severity of mitral regurgitation. Both longitudinally and transversely, broad infarction leads to the enlargement of the mitral anulus. However, even if the mitral anulus is not so dilated, severe involvement of either commissural area results in severe mitral regurgitation from the same commissural side. Thus, there are two major causative factors of mitral regurgitation: (1) asynergy of the papillary muscle or the ventricle that results in mitral regurgitation located in the commissural area of the same side as asynergy, and (2) enlargement of mitral anulus, which results in regurgitation from the central area of the orifice.(ABSTRACT TRUNCATED AT 250 WORDS)

Visualization of right atrial thrombus associated with constrictive pericarditis by indium-111 oxine platelet imaging

A right atrial thrombus is not often seen and only a few reports of visualization have been described. We report a 44-yr-old man who had a large atrial thrombus associated with constrictive pericarditis. Two-dimensional echocardiography and computed tomography showed a large right atrial mass. Indium-111 oxine platelet deposition was demonstrated on the surface of thrombus by platelet imaging. Platelet imaging was useful for differential diagnosis from cardiac tumor, and as an indication for surgical treatment, since right atrial thrombus may have a high risk of pulmonary embolism or severe right heart failure.

[The physiological role of the pericardium: studies based on right heart inflow dynamics in cases of left-sided pericardial defect]

Using pulsed Doppler echocardiography, the effects of postural change on the blood flow pattern in the superior vena cava and in the right ventricular inflow tract were investigated to evaluate the physiological role of the pericardium. Eight cases of left-sided pericardial defect and eight healthy subjects were examined. 1. Suppressed inflow into the right atrium during systole in left-sided pericardial defect was manifested as a reduction of the systolic wave (S) in the superior caval vein and impairment of the systolic shift of the tricuspid annulus. This suppression suggested unsatisfactory volume expansion in the right atrium due to the absence of negative intrapericardial pressure. 2. In left-sided pericardial defect, the right ventricular inflow pattern differed from the normal, most distinctly in the right lateral recumbent position, though the cardiac motion was nearly identical with that of the normal in this position. In this position, the ratio of the peak velocity of presystolic filling to that of rapid filling was increased, and the deceleration half time of rapid filling was prolonged. These findings indicated that the right ventricular rapid filling was retarded, and was compensated by the filling due to atrial contraction. It is assumed that right ventricular filling is influenced by hydrostatic pressure due to changes in posture in the absence of restriction by the pericardium. 3. It is concluded that the pericardium maintains negative intrapericardial pressure, so that each cardiac chamber is uniformly expanded for its filling, and that this function minimizes the influence of posture on cardiac hemodynamics.

Diagnosis of mitral valve perforation by real-time two-dimensional Doppler flow imaging technique

It has been difficult to diagnose mitral regurgitation due to valve perforation using either noninvasive or invasive methods, differentiating it from that resulting from incomplete coaptation of the mitral valve. This report describes three patients with infective endocarditis and mitral valve perforation, which was definitively diagnosed by the real-time two-dimensional Doppler flow imaging technique. In these three patients, B-mode echocardiography demonstrated an echo interruption on the anterior mitral leaflet. However, it was not certain whether this interruption was simply an echo dropout or indicated an interruption of the valve tissue. Doppler flow imaging then demonstrated unusual flow in the vicinity of the echo interruption, which appeared to flow from the left ventricular cavity into the left atrial cavity across the midportion of the anterior mitral valve leaflet during systole and in the opposite direction during diastole. This was interpreted as mitral valve perforation. In general, Doppler flow imaging may play a complementary role with B-mode echocardiography in cardiac diagnosis.

Primary failure of Hancock porcine bioprosthetic valves: two dimensional echocardiographic assessment

To reveal the process of primary failure of the Hancock porcine bioprosthetic heart valve, a real-time two-dimensional echocardiography was undertaken. There were 75 cases (84 valves) with 26 in the aortic valve position, 39 in the mitral valve position, 9 in both the aortic and mitral valve positions, and 1 in the tricuspid valve position. The subjects comprised 35 males and 40 females, whose ages ranged from 18 to 65 years with a mean of 44.7 years. Valvular changes such as thickened valve cusps or abnormal valve movement were observed in 27 (32%) of the 84 valves; more specifically, in 5 (14.3%) of the 35 aortic valves and in 22 (45.8%) of the 48 mitral valves, indicating that valvular changes occurred most frequently in the mitral valve position (p less than 0.01). In the period between valve replacement surgery and the appearance of valvular changes, no significant difference was noted between aortic and mitral valve bioprostheses. The duration ranged from 14.5 to 74.5 months with a mean of 50.2 months. Valvular changes were evident in more than 50% of the valve bioprostheses implanted 6 or more years ago. In the mitral valve position, valve cusp changes appeared more frequently at the anterior cusp than at the inner and outer cusps. The frequency was 17 cases at the anterior cusp, 6 at the inner and 9 at the outer. In 7 of the 11 cases followed up after the appearance of valvular changes, an increase in the changes was recognized 7.5 to 29.5 months (a mean of 16.4 months) later.(ABSTRACT TRUNCATED AT 250 WORDS)

[Pericardial defect: roles of the pericardium on kinetoanatomic changes of the heart influenced by patients' postures]

To elucidate the physioanatomic roles of the pericardium, the alterations in gross anatomy and cardiac motion induced by posture were examined by two-dimensional echocardiography in seven patients with total absence of the left pericardium. Ten healthy subjects were served as controls. The heart was located deeper within the chest at end-diastole in patients with pericardial defect than in healthy subjects, especially in the left lateral decubitus position. With progression of systole, the cardiac apex swung anteriorly with the cardiac base as the fulcrum, and the heart approximated the normal position at end-systole. The deeper the position of the center of the cross-section of the left ventricular cavity at end-diastole, the more exaggerated the swinging motion in systole. The deep location of the heart in end-diastole is considered to result from release from pericardial support, and the systolic tonus of the cardiac muscle restores the apex to nearly normal position. The characteristic swinging motion of the heart and its alterations dependent of posture seemed the signs suggestive of total absence of the pericardium. The shape of the short-axis view of the left ventricular cavity was nearly circular throughout the cardiac cycle. Therefore, paradoxical motion of the ventricular septum observed on M-mode echocardiography in pericardial defect results from the anterior shift of the entire heart overcoming the proper motion of the interventricular septum. The left ventricular dimension become enlarged according to the postural change from the right to left lateral decubitus positions regardless of the presence or absence of the pericardium. The right ventricular cavity became enlarged in the left lateral decubitus position in patients with pericardial defect. The elevation of hydrostatic pressure due to postural change was considered excessive due to the absence of the pericardium. In the left lateral decubitus position, systolic excursions of the mitral and tricuspid rings became more prominent in healthy subjects, whereas these excursions, particularly of the tricuspid ring, were reduced in patients with pericardial defect. Depressed tricuspid ring motion was also observed in the right lateral position in cases with pericardial defects. The reduced excursion of the tricuspid, ring and the right ventricular dilatation may affect systemic venous return to the right atrium.

Smoke-like echo in the left atrial cavity in mitral valve disease: its features and significance

In some patients with mitral stenosis, a smoke-like echo is observed in the left atrial cavity. The present study in 116 consecutive patients with rheumatic mitral valve disease investigated the echocardiographic features and clinical significance of this echo. The smoke-like echo is characterized by the following echocardiographic features: 1) it is composed of numerous microechoes; 2) it curls up slowly in the enlarged left atrial cavity; and 3) it vanishes as soon as it pours into the ventricular cavity. Hemostasis in the left atrial cavity was considered to be an important underlying condition for development of the echo. Hemorheologic conditions indicated that the shear rate of blood flow in the left atrial cavity was calculated to be low enough for the development of red blood cell aggregation. These conditions suggest that the source of the smoke-like echo might be aggregated cells due to hemostasis in the left atrial cavity. Left atrial thrombi were detected in many patients who had this echo in the left atrial cavity. Although it has not been conclusively determined that the presence of the smoke-like echo is a necessary condition for thrombus formation, this echo appears to be closely related to thrombus formation in the left atrial cavity. It is concluded that the presence of this echo indicates severe left atrial hemostasis and is a warning for thrombus formation.

[Two-dimensional echocardiography in diagnosing the region of myocardial infarction: a comparative study by several independent examiners]

The efficacy of two-dimensional echocardiography in diagnosing the localization of myocardial infarction (MI) was studied by comparing the echocardiographic and pathological findings of 28 patients having MI. The ventricular wall was divided into 18 segments including three segments of the right ventricular wall. The regional wall motion abnormalities for each of the 504 segments were diagnosed by visual assessment. The echocardiographic recordings were reviewed individually by four examiners using the same protocol to assess the interobserver's variation. The receiver operating characteristics (ROC) curves differed by examiners. However, when the subjects were limited to anterior MI patients, the ROC curves established by the echo-trained physicians did not differ significantly. It was concluded that the echocardiographic diagnosis of regional wall motion by visual assessment has universal validity. Individual differences are thought mainly to depend on the sites of infarction. Sensitivities for detecting transmural (TM), non-transmural (non-TM) infarcted segments and intact segments were 90, 70 and 70%, respectively. Most of the underestimated TM or overestimated intact segments corresponded to the sites adjacent to MI. As the unexpectedly misdiagnosed segments, the mimic inward motion of the inferior wall drawn by the intact anteroapical wall was observed in a inferior MI patient, or the mimic anterior motion of the anteroapical wall by a swinging motion of the heart, or the paradoxical motion of the interventricular septum was observed in a right ventricular MI case. In the two third of the overestimated non-TM segments, it was considered that the wall motion was affected by the myocardial ischemia, which was not revealed by pathological examination. The underestimated non-TM segments located adjacent to the intact segments or opposite to the severely ischemic segments. From the echocardiographic viewpoint, nearly 90% of segments showing akinetic or dyskinetic motion had MI. However, one third of segments diagnosed as normal were actually MI segments.

Doppler echocardiographic features of ventricular septal rupture in myocardial infarction

Doppler echocardiography was used to evaluate the features of interventricular septal rupture in six patients with acute myocardial infarction and to substantiate the hemodynamic data and morphologic findings at surgery or autopsy. Although echocardiographic visualization of the septal rupture was obtained in only two of the six patients, unusual Doppler flow signals were detected in the apical portion of the right ventricle in all six patients. Five patients had unusual flow signals during both systole and diastole; one had such signals only during systole. The location of these unusual flow signals coincided with the site of septal rupture confirmed at surgery or autopsy. The pattern of the flow signals in one cardiac cycle was very similar to that of the pressure difference between the left and right ventricular cavities. These findings indicate that the unusual flow signals represent the left to right shunt flows resulting from septal rupture. In conclusion, Doppler echocardiography may be a very useful tool for diagnosing interventricular septal rupture easily and noninvasively in patients with acute myocardial infarction.

[Analysis of left ventricular blood flow in cases of myocardial infarction: a preliminary report]

Analysis of left ventricular blood flow in cases of myocardial infarction was attempted by two-dimensional Doppler echocardiography. Subjects consisted of 25 cases of myocardial infarction with and without ventricular aneurysm, and 15 healthy persons as controls. The Doppler recordings were made in nine areas within the left ventricular cavity from the apical approach. For healthy subjects, ejection flows were recorded in the main cavity and directed towards the aortic orifice in systole, and diastolic flows in the left ventricular inflow were recorded from the mitral orifice to the apex. However, diastolic flows toward the aortic orifice were also recorded along the interventricular septum, and interpreted as eddy currents from the apical cavity. There were no high velocity flows in the phases of isometric contraction and relaxation. In seven of 25 cases of myocardial infarction, abnormally high velocity flows of more than 30 cm/sec were recorded in the isometric relaxation phase, which were directed away from the asynergic part. In eight of the 25 patients examined, high velocity flows toward the cardiac apex were recorded at the posteroapical area in systole. Such flows have never been observed in healthy subjects. Inertia of the diastolic mitral inflow is considered to continue during systole due to impairment of contractions of the apicoinferior wall.

[Left ventricular thrombus formation and cuspal fusion of the prosthetic valve during left heart bypass: their pathophysiological significance and echocardiographic observations]

The echocardiographic findings during left ventricular assist of a heart of a 36-year-old woman who underwent mitral valve replacement were described. Blood was bypassed from the left atrium to the aorta. Echocardiography demonstrated that the pulmonary and tricuspid valves functioned with each heart beat, but that the aortic and prosthetic mitral valves did not open, and the left ventricular wall did not contract. In the left ventricular cavity, there was a mobile and amorphous thrombus which correlated with dynamic intracavitary micro-echoes ("moya moya" echoes). With higher left atrial pressure, the left ventricular motion increased slightly, and the left ventricular dimension gradually decreased. These findings were interpreted as follows: (1) desired results were attained from the previous powerful assist, or (2) the most optimum pressure of the left atrium in relation to the left ventricle was relatively high. It has not yet been determined which is actually the case. The "moya moya" and thrombus echoes were decreased. The general condition of the heart appeared to be improved, but the prosthetic valve motion was not observed. Contrast study via an echocardiographically-guided catheter inserted retrogradely into the left ventricular cavity revealed prosthetic valve stenosis. Fusion of its cusps by fibrin was confirmed on repeat surgery. Although the patient's condition allowed removal of the left ventricular assist device after surgery, the patient died of progressive infection. Optimum powerful assist should be performed while the formation of thrombi and cuspal adhesions is being prevented by other methods, or a more mild assist may be desirable.(ABSTRACT TRUNCATED AT 250 WORDS)