Catheter Ablation of Left Parietal Accessory Pathways

Fifty-one patients with a left parietal pathway and drug refractory tachycardia underwent transcatheler ablation of their accessory pathway. Three had single concealed pathways, two had multiple pathways, and the remaining 46 had the Wolff-Parkinson-While syndrome. Two patients were resuscitated from a cardiac arrest related to a ventricular fibrillation. A multipolar (quadri-, hexa-, or octopolar) electrode catheter was positioned within the coronary sinus in order to localize the pathway accurately. An ablation catheter was then introduced either through a patent foramen ovale (11 patients), by transseptal catheterization (14 patients) or a retrograde arterial catheterization (26 patients). The mitral annulus was mapped with this catheter during orthodromic tachycardia in order to record ventriculoatrial (VA) time as short as (or even shorter than) that recorded in the coronary sinus. The VA time in our series was 82 ± 13 msec. Two 160-joule cathodal shocks were delivered at this site and eventually repeated according to the results (73 sessions/51 patients). The mean cumulative energy was 650 ± 205 joules. No significant side effects occurred except one case of a right coronary artery spasm leading to inferior wall infarction. During follow-up of 2–49 months, all but two patients were free of tachycardia. Twelve patients were reassessed 4 to 8 months after the procedure: conduction over the pathway was absent, and no vascular damage was noticed. Catheter ablation of left parietal accessory pathways is both effective and safe. Ablation by retrograde arterial catheterization was as efficient as the tranxseptal approach. This method is an attractive alternative to surgery.     

Adverse events in patients treated with 5-aminosalicyclic acid: 1993–1994 pharmacovigilance report for Pentasa in France

Background : The incidence of the side-effects of 5-aminosalicylic acid (5-ASA) in clinical practice is not known.
Aim : To present the safety reports on the use of Pentasa in France.
Methods : Pentasa-related adverse events were recorded from 1 January 1993 to 31 December 1994. Spontaneous reports to Ferring S.A. came from physicians or pharmacovigilance regional centres.
Results : In 1993 and 1994, 51 and 79 adverse events were reported; the estimated gross incidence was 6.6 and 9.0 per million days of therapy. Detailed information was obtained in 64% of cases in 1993 and 53% in 1994. Adverse events with a high likelihood of causalty included five cases of diarrhoea, 14 cases of pancreatitis, seven cases of liver abnormalities, seven of blood dyscrasias, two cases of renal insufficiency (one of which was in a fetus), and eight of cardiac disorders including three myocarditis.
Conclusions : Pentasa seldom has adverse effects. The majority of the adverse events do not seem to be dose-related. Clinicians should be aware of exceptional but severe adverse events including pancreatitis, cardiac disorders, blood dyscrasias and renal insufficiency.     

Elevated levels of basic fibroblast growth factor in megakaryocytes and platelets from patients with idiopathic myelofibrosis

Idiopathic myelofibrosis, or agnogenic myeloid metaplasia, is a chronic myeloproliferative disorder characterized by clonal expansion and marrow fibrosis. Although marrow fibrosis appears to be a reactive process, it substantially contributes to impaired haemopoiesis. During the last few years the implication of megakaryocyte-derived growth factors in its pathogenesis has been documented.
We previously reported increased expression of TGF-β in patients with idiopathic myelofibrosis. In the present study we show that circulating megakaryocytic cells from such patients expressed high levels of basic fibroblast growth factor (bFGF). An increased expression of bFGF was also detected in patients' platelets. Under culture conditions, bFGF present in megakaryocytic cells was not exported into the medium, consistent with the fact that bFGF is devoid of a secretion peptide signal. Interestingly, this lack of bFGF secretion was observed in all patients but one, who was in an accelerated phase of the disease and presented an important percentage of circulating megakaryoblasts.     

Myelolipoma of the adrenal gland: sonographic and CT features

The radiologic findings in 13 patients with pathologically proved adrenal myelolipomas were reviewed. All lesions involved the right adrenal gland; they ranged from 2 to 9 cm in diameter. Sonograms showed hyperechoic tumors in 11 cases (five homogeneous, six heterogeneous). Two myelolipomas composed primarily of myeloid tissue were hypoechoic. A propagation speed artifact was seen in seven lesions, all of which were composed primarily of fat and larger than 4 cm. CT identified fat-density tissues in all lesions. Contrast-enhanced CT showed positive attenuation values in the two predominantly myeloid tumors. CT appears to be sensitive for the diagnosis of adrenal myelolipomas. However, precontrast images are required to avoid errors.     

MR imaging of adrenal myelolipomas

The magnetic resonance (MR) images in six patients with seven adrenal myelolipomas are presented. Four lesions involved the right gland, and three the left; they ranged from 3 to 12.5 cm in diameter. Magnetic resonance was able to image all lesions. Using T1-weighted sequences, three structural patterns were observed; (a) homogeneous masses with intensity equal to adjacent fat (three cases); (b) heterogeneous masses with fat intensity areas and areas similar to renal cortex (two cases); and (c) nodules quite different from fat, hypointense to the liver (two cases). On T2-weighted images, myelolipomas were slightly hypointense to fat and either hypo- or isointense to the liver. A comparison with the results of CT studies was possible in all cases, and good correlation with determination of the presence and quantity of fat density tissues within the lesions was observed. However, MR imaging did not seem to help in diagnosing adrenal myelolipoma in patients with equivocal CT findings, and needle biopsy is still needed in difficult cases.     

Congenital anomalies and anatomical variants of the inferior vena cava and left renal vein: noninvasive diagnosis with duplex Doppler sonography

The sonographic findings in five patients with congenital anomalies of the interior vena cava and left renal vein are presented. We encountered two patients with duplication and two with transposition of the inferior vena cava, and one with a retroaortic left renal vein, In four cases the findings were confirmed by demonstrating venous flow within the anomalous vascular structures using duplex Doppler equipment. The diagnostic capabilities of sonographic imaging and Doppler analysis of blood flow allow noninvasive recognition of these vascular anomalies. In our opinion, invasive studies are needed only when retroperitoneal structures are difficult to assess by ultrasound because of obesity and/or abundant overlying intestinal gas.     

Anti-idiotypic antibodies specific for a pathologic anti-Pr2 cold agglutinin

The heterogeneity of human red cell (RBC) autoantibodies may be assessed by using anti-idiotypic antibodies. In this study, mouse monoclonal anti-idiotypic antibodies were produced against a pathologic RBC autoantibody with anti-Pr2 specificity. Epstein-Barr virus-transformed B-cell clones were established from a patient who had splenic lymphoma and associated immune hemolysis due to an anti-Pr2 cold autoantibody. Two of the eight clones producing this autoantibody were used to immunize mice for the establishment of hybridomas, and four monoclonal anti-idiotypic antibodies were isolated (2 IgG1 kappa and 2 IgM kappa). By the use of these anti-idiotypic antibodies, strong crossreactivity was seen on enzyme-linked immunosorbent assay with other anti-Pr2-producing clones from the same patient, but no cross-reactivity was seen with RBC autoantibodies from other individuals having anti-Pr or different specificities. Each of the anti-idiotypic antibodies inhibited hemagglutination (HA) by the patient's anti-Pr2 but failed to inhibit HA by antisera of a different RBC specificity. Cross-competition experiments indicated that all of the anti-idiotypic antibodies may recognize the same or a closely related idiotope on the anti-Pr2 autoantibody. These studies suggested that the four anti-idiotypic antibodies are directed against the same (or closely related) idiotypic determinant(s), unique to this patient's anti-Pr2 and located at or near the antigen-binding site. These anti-idiotypic antibodies may be useful tools for the study of this autoimmune response or for the development of immune therapeutic agents.(ABSTRACT TRUNCATED AT 250 WORDS)     

Appendices epiploicae of the large bowel. Sonographic appearance and differentiation from peritoneal seeding

Solid hyperechogenic nodules of different sizes and shapes surrounded by ascitic fluid were seen growing from the peritoneal surface of the large bowel in three patients with biopsy-proven alcoholic liver cirrhosis; they were spaced at regular intervals along the course of the colon. The same images were visible during in vitro examination of two surgical specimens of the large bowel and corresponded to appendices epiploicae of different sizes. The appendices epiploicae can be identified by sonography only when surrounded by fluid; their shape may be similar to that of peritoneal tumors. Careful analysis of both the relationships of the appendices epiploicae with the outer surface of the large bowel and of their regular spacing along the course of the colon itself may help to avoid possible misinterpretations.