Aneurysm of the ventricular membranous septum: serial echocardiographic studies.

OBJECTIVES: The aim of this article is to examine the frequency, timing of formation of aneurysm of the ventricular membranous septum (AVMS), and prognosis in patients with a perimembranous ventricular septal defect (VSD). PATIENTS: One hundred forty-eight patients were diagnosed with a perimembranous VSD within 90 days after birth. They were classified into three groups: Group I, spontaneous closure; Group II, open; Group III, surgical closure. They were also divided into two further groups: 75 patients with congestive heart failure (CHF) and 73 patients without that. METHODS: An AVMS was observed by two-dimensional echocardiography, and spontaneous closure of the VSD was confirmed by color Doppler. RESULTS: An AVMS was formed in 69 (47%) of 148 patients: 50% in Group I, 66% in Group II, 15% in Group III. The timing of AVMS formation was at a median age of 6 months. In 14% of patients, AVMS was formed within 3 months of age. The frequency of AVMS at the time of the initial echocardiogram was low in patients with CHF (odds ratio, 3.23; 95% confidence interval, 1.19-8.79 p = 0.017). CONCLUSIONS: We believe that AVMS formation is related to avoidance of surgical closure during early infancy in patients with a perimembranous VSD, because the frequency of AVMS during early infancy is low in patients with CHF.

Abnormal cardiac autonomic nervous activity after right ventricular outflow tract reconstruction.

BACKGROUND: There are few studies of cardiac autonomic nervous activity (CANA) in patients with congenital heart disease. Methods and Results-We evaluated CANA in 54 patients after closure of an atrial/ventricular septal defect (group A), 54 patients after successful right ventricular outflow tract reconstruction (RVOTR) (group B1), 35 RVOTR patients with residual stenosis (group B2), and 47 controls. Cardiac parasympathetic nervous activity (PSNA) was estimated by heart rate (HR) change after cholinergic blockade, HR variability, and arterial baroreflex sensitivity (BRS). Cardiac sympathetic nervous activity was estimated by the heart-to-mediastinum (123)I-metaiodobenzylguanidine activity ratio (H/M) and HR increase after isoproterenol infusion (ss). HR response (DeltaHR) and peak oxygen uptake (VO(2)) were measured by exercise test. There was no difference in ss among study groups. Group A exhibited mildly impaired PSNA, which recovered 1 year after surgery, and no change in H/M. Impaired PSNA and low H/M were found in groups B1 and B2 compared with controls (P<0.001), although the PSNA tended to recover 1 year after re-RVOTR. In group B1, PSNA and ss were related to DeltaHR, and BRS correlated inversely with the number of surgical procedures and age at RVOTR and positively correlated with the follow-up period, whereas DeltaHR correlated with peak VO(2) (P<0.01 to 0.001). CONCLUSIONS: After RVOTR, postsynaptic ss-sensitivity is maintained and is important in DeltaHR during exercise, as is PSNA, although ventricular sympathetic denervation is common. Impaired PSNA immediately after RVOTR improves with improved DeltaHR and results in future amelioration of aerobic capacity, whereas ventricular sympathetic reinnervation is uncertain.

Comparison of the right and left ventricle as a systemic ventricle during exercise in patients with congenital heart disease.

BACKGROUND: Few studies have investigated the clinical advantages of surgical correction with the morphologic left ventricle (MLV) instead of the morphologic right ventricle as a systemic ventricle (SV) in patients with congenital heart disease. METHODS: Twenty-four healthy control subjects (group A1), 6 patients with isolated congenitally corrected transposition of the great arteries (TGA) (group A2), 16 patients with TGA who had undergone an arterial switch operation (group B1), 18 patients with TGA who had undergone a venous switch operation (group B2), 9 patients with atrioventricular and ventriculoarterial discordance who had undergone a double switch operation (group C1), and 6 patients with atrioventricular and ventriculoarterial discordance who had undergone a conventional external conduit operation from the MLV to the pulmonary artery (group C2), performed treadmill exercise testing. Their heart rate (HR), oxygen uptake (VO2), and oxygen pulse (O2 pulse), which reflects individual stroke volume, were measured, and contractile function was assessed by echocardiography. RESULTS: The peak HR for the patients after a definitive operation were significantly lower than that in group A1 and was correlated with peak VO2 (r =.67, P <.0001). The peak VO2 and peak O2 pulse for the groups A2 and B2 were significantly lower than those for the groups A1 and B1, respectively. The peak O2 pulse data were strongly correlated with those of peak VO 2 (r = 0.91, P <.0001). The left ventricular ejection fraction was significantly lower in groups B1 and C1 than in group A1 and was correlated with peak VO 2 (r =.50, P <.01). No significant differences in VO2, HR, and O 2 pulse at peak exercise were observed between groups C1 and C2. CONCLUSIONS: Chronotropic incompetence and an impaired response of the stroke volume of the MRV during exercise are partly responsible for the reduced exercise capacity in groups A2 and B2 compared with groups with the MLV as an SV, and the SV function at rest is also related to exercise capacity. Superiority of the double-switch operation compared with the conventional conduit operation was not observed. A longer-term follow-up is necessary before the advantages of these 2 operations can be compared.

Spontaneously immortalized adult mouse Schwann cells secrete autocrine and paracrine growth-promoting activities.

We established spontaneously immortalized Schwann cell lines from long-term cultures of adult mouse dorsal root ganglia and peripheral nerves. One of the cell lines, designated IMS32, responded to mitogenic stimuli by platelet-derived growth factor (PDGF)-BB, acidic and basic fibroblast growth factors (aFGF, bFGF), and transforming growth factors (TGF)-beta 1 and -beta 2, as determined by bromodeoxyuridine (BrdU) incorporation and double immunofluorescence for S100 and BrdU. Furthermore, conditioned media (CM) obtained from IMS32 cells showed mitogenic activity for both IMS32 cells and long-term cultured Schwann cells. Western blot analysis revealed TGF-beta-like molecule in the CM, and the activity was absorbed with anti-TGF-beta neutralizing antibody. Reverse transcription followed by polymerase chain reaction (RT-PCR) of IMS32 RNA revealed that these cells expressed TGF-beta 1, -beta 2, and -beta 3 transcripts. When rat pheochromocytoma PC12 cells were incubated with the CM, they developed neurite growth. Coculture of PC12 and IMS32 cells also showed neurite growth of PC12 cells. RNA transcripts of nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT3), ciliary neurotrophic factor (CNTF), and glial cell line-derived neurotrophic factor (GDNF) were detected from IMS32 cells by RT-PCR. In these, we sequenced the mouse GDNF cDNA coding region and observed 97% and 90% homologies to corresponding rat and human cDNA sequences, respectively. These results indicate that the immortalized Schwann cell line mitotically responds to various growth factors and secretes autocrine and paracrine growth-promoting activities in vitro.

Mitogenic effects of platelet-derived growth factor, fibroblast growth factor, transforming growth factor-beta, and heparin-binding serum factor for adult mouse Schwann cells.

Mitogenic effects of fetal calf serum (FCS), platelet-derived growth factor (PDGF), fibroblast growth factor (FGF), transforming growth factor-beta (TGF-beta), and forskolin to adult mouse Schwann cells were examined by bromodeoxyuridine (BrdU) incorporation and double immunofluorescence for S100 and BrdU. PDGF-BB, basic FGF, and TGF-beta 1 and beta 2 were all mitogenic for Schwann cells in media containing FCS. Forskolin suppressed the mitogenic activity of these factors. In serum-free media, PDGF-BB and bFGF were also mitogenic, but TGF-beta 1 and beta 2 were not. Heparin-binding fractions of FCS obtained by heparin-Sepharose chromatography synergized with TGF-beta 1 and beta 2 to produce a mitogenic response. Since PDGF-BB, acidic FGF, and basic FGF were not detected in these fractions by immunoabsorption and immunoblot assays, the presence of unidentified heparin-binding molecules in FCS bioactive for adult mouse Schwann cells is suggested.

Herpes zoster ophthalmicus with delayed contralateral hemiparesis.

A 35-year-old previously healthy woman developed left hemiparesis sixteen weeks after the onset of right herpes zoster ophthalmicus. Cerebral angiography showed complete occlusion of right middle cerebral artery at the origin and segmental narrowing of the right posterior cerebral artery. Computerized tomography (CT) and magnetic resonance imaging (MRI) also revealed a right hemispheric lesion consistent with angiographic findings. Reports from the literature along with the present case suggest that arteritis followed by cerebral infarction is the most probable cause of delayed contralateral hemiparesis.

[Xenon CT CBF mapping derived from two minutes inhalation].

Although xenon enhanced CT method for local cerebral blood flow measurement has been brought into a clinical practice, the technique has inherent limitations including anesthetic effects and expensive cost of xenon by a large consumption. To overcome these problems a modified method with a short-duration inhalation was developed and its validity was attested. Siemens Somatom SF with a resolution of 256 X 256 pixels and a scan time of 10 seconds was used. The subjects inhaled 50% Xe/O2 gas mixture from an apparatus consisted of Douglas bag and an open circuit. Xenon concentration in the expired gas was continuously monitored and estimated for arterial blood concentration by using a hematocrit correction. PaCO2 was monitored throughout the study. At the starting point and the endpoint of the inhalation two scans were performed respectively. Thus obtained four images were processed for CT noise cancellation, summation and subtraction to produce an in vivo autoradiography image. Local CBF was calculated from equations derived from the autoradiographic technique with a fixed partition coefficient of lambda = 1. Computer simulation studies were performed to find the optimal scan point to obtain an autoradiographic image and to estimate the calculation errors of this method. One minute and forty-five seconds was found to be the optimal scan point to gain an autoradiographic image in view of a balance between linearity of CBF/enhancement curve and total amount of tissue enhancement. The theoretical errors due to the assumption for a fixed partition coefficient were calculated to be 8% underestimation for gray matter and 5% overestimation for white matter.(ABSTRACT TRUNCATED AT 250 WORDS)