Electrophysiological Characteristics of Localized Reentrant Atrial Tachycardia Occurring After Catheter Ablation of Long-Lasting Persistent Atrial Fibrillation

Background: Mapping of recurrent atrial tachycardia (AT) after extensive ablation for long-lasting persistent atrial fibrillation (AF) is complex. We sought to describe the electrophysiological characteristics of localized reentry occurring after ablation of long-lasting persistent AF.
Methods: Out of 70 patients undergoing catheter ablation of long-lasting persistent AF, 9 patients (13%, 55 ± 8 years, 8 males) in whom localized reentry was demonstrated in a repeat ablation were studied. Localized reentry was defined as reentry in which the circuit was localized to a small area and did not have a central obstacle. The mechanism of AT was determined by electroanatomical and entrainment mapping.
Results: Nine localized reentries with cycle length of 243 ± 41 ms were mapped in 9 patients. The location of AT was the left atrial appendage in 4 patients, anterior left atrium in 2, left septum in 2, and mitral isthmus in 1. In all ATs, a critical isthmus of <10 mm in width was identified in the vicinity of the prior linear lesions or ostia of isolated pulmonary veins. Ablation of the critical isthmus, which was characterized by continuous low-voltage activity (median voltage: 0.15 mV, mean duration: 117 ± 31 ms), terminated AT and rendered it noninducible. Additionally, ablation was performed for all of inducible ATs. At 11 ± 7 months after the procedure, 8 of 9 patients (89%) were free from any arrhythmias.
Conclusions: After ablation of long-lasting persistent AF, localized reentry may arise from a site in the vicinity of the prior ablation lesions. Ablation of the critical isthmus eliminates the arrhythmia.     

Successful Prevention of Recurrent Ventricular Fibrillation by Intravenous Isoproterenol in a Patient with Brugada Syndrome

TANAKA, H., et al. : Successful Prevention of Recurrent Ventricular Fibrillation by Intravenous Isoproterenol in a Patient with Brugada Syndrome. Intravenous administration of isoproterenol restored the ST-segment configuration to nearly normal in the right precordial leads and completely prevented spontaneous VF attacks in a patient with Brugada syndrome. The formation of a Brugada-type ECG has been attributed to the transmural dispersion of repolarization of the right ventricular epicardium and related to modulation of the autonomic nervous system. Our case may provide clues to the pathophysiological mechanism of this syndrome.     

Analysis of Met235 to Thr variant of the angiotensinogen gene in relation to the blood pressure and family history of essential hypertension in Japanese children

A recent study reported a significant relationship between a T⁷⁰⁴→C (Met²³⁵→Thr) variant in exon 2 of the angiotensinogen gene in adults and essential hypertension. In the present study, this variant was detected in 131 Japanese children using a polymerase chain reaction. The allele frequency of the variant was 0.76. The genotype frequency of the homozygote for the allele was 0.59, and children who were homozygous had higher systolic blood pressure than those with the other two genotypes. No relationship was found between children's polymorphism and a family history of essential hypertension. These findings suggest that this molecular variant of the angiotensinogen gene may play some role in the regulation of blood pressure in Japanese children.     

Serum level and gene polymorphism of angiotensin I converting enzyme in Japanese children

The aim of the present study was to determine the distribution of the insertion/deletion polymorphism of angiotensin I converting enzyme (ACE) gene in Japanese children. In addition, the relationship between this polymorphism and serum ACE levels in the same population were analyzed. Insertion/deletion polymorphism located in intron 16 of the ACE gene was examined by polymerase chain reaction in Japanese children aged 10–15 years. Allele frequencies were 0.64 for the insertion allele and 0.36 for the deletion allele in 122 subjects. No association was found between genotypes in this polymorphism and the level of systolic or diastolic blood pressure. A significant relationship between this polymorphism and serum ACE activity was observed. These results suggest that interindividual variability of serum ACE level is strongly influenced by the ACE genotype as early as in childhood.     

Lingual cyst in infancy: Importance of palpation for diagnosis

Two infants, 5 and 12 weeks of age, with lingual cysts were presented. Histological findings were compatible with a salivary retention cyst in one and a thyroglossal duct cyst in the other. Both infants were admitted to our hospital because of severe stridor that had developed from one to two weeks of age. Their lingual cysts were easily recognizable by simple palpation and were confirmed by non-invasive imaging techniques, such as ultrasound sonography, computed tomography and magnetic resonance imaging. Lingual cyst in infancy may be large enough to cause stridor and dyspnea, and occasionally result in sudden infant death, although once diagnosis is made a radical operation can be easily performed. Therefore, it is important that palpation in the oral cavity should be performed with all infants with persistent stridor as a part of a physical examination.     

Comprehensive treatment of advanced neuroblastoma involving autologous bone marrow transplant

Encouraging results are reported with high-dose chemotherapy and total body irradiation followed by autologous bone marrow transplantation in the treatment of advanced neuroblastoma. However, relapse remains a significant problem. We used high-dose chemotherapy, surgery, intraoperative radiation and an autologous bone marrow transplant treated in vitro to remove tumor cells followed by 13-cis-retinoic acid to treat 36 children with advanced neuroblastoma. This comprehensive treatment appears to improve the survival rate of patients with advanced neuroblastoma, including those with N-myc amplification and bony involvement. The disease-free survival rate was 66% (95% confidence interval, 49–84%) at 3 years. All patients who received 13-cis-retinoic acid developed cheilitis, but no bone marrow depression occurred in these patients. Five patients developed hemolytic uremic syndrome (HUS) post-transplant. This may have been related to the procedure used for total body irradiation. Patients who had their kidneys shielded during this procedure did not develop this syndrome. Patients who received local irradiation at the primary site showed no evidence of relapse in this region, indicating that such therapy may help to prevent a relapse. These data suggest a high rate of 3 year disease-free survival with this treatment strategy. The nonrandomized nature of the study and use of multiple modalities precludes analysis of the specific contribution of each.     

Treatment of a stage I testicular yolk sac tumor with vascular invasion

There is controversy concerning the treatment of stage I yolk sac tumor of the testis, particularly of those with histological factors that indicate a high risk of relapse. Usually orchiectomy alone is sufficient and adjuvant chemotherapy is unnecessary. Retroperitoneal lymphadenectomy is indicated for patients with persistently high alpha-fetoprotein. Once recurred, treatment at that time is thought to be curative. However, postoperative chemotherapy may be necessary for patients with a tumor expressing histological factors that predict possible relapse. In this paper we report on a case of a 2 year old boy whose tumor invaded the testicular veins. The patient suffered from recurrent disease but was successfully treated by chemotherapeutic regimens including cisplatin and retroperitoneal lymphadenectomy. The importance of the histological factors in making a decision on the treatment strategy for stage I testicular yolk sac tumor is discussed.     

Prevention of antibiotic-associated diarrhea in children by Clostridium butyricum MIYAIRI

BACKGROUND: Clostridium butyricum MIYAIRI (CBM) is a probiotic bacteria used for anti-diarrheal medicine in Japan. The preventive effect of CBM was investigated for antibiotic-associated diarrhea (AAD) in children. METHODS: One hundred and ten children who suffered from upper respiratory tract infection or gastroenteritis were divided into three groups. Twenty-seven of the patients received only antibiotics, 38 received CBM from the mid point of the antibiotic treatment and 45 concomitantly received CBM from the beginning of the antibiotic treatment. To examine the effects of CBM on AAD, the changes in intestinal flora were investigated. RESULTS: Diarrhea was observed in 59% of the subjects who received only antibiotics, and total fecal anaerobes, especially Bifidobacterium, were remarkably decreased. In contrast, diarrhea in the subjects who received CBM from either the middle or the beginning of the antibiotic therapy was decreased to 5% and 9%, respectively. Concomitant administration of CBM increased anaerobes and prevented the decrease of Bifidobacterium in the subjects who received antibiotics. CONCLUSIONS: Clostridium butyricum MIYAIRI is effective for both the treatment and the prophylaxis of AAD in children, as it normalizes the intestinal flora disturbed by antibiotics.     

Distinctive portal venographic pattern in patients with sclerotherapy resistant oesophageal varices

Abstract  We performed prophylactic sclerotherapy in 350 patients with 'high risk' oesophageal varices (F2 or F3 with a moderate or severe red colour sign). Of these patients, eight exhibited sclerotherapy resistance (i.e. no significant reduction in the size of varices after five sessions of sclerotherapy). Thus, the prevalence of sclerotherapy resistant varices was 2%. Of 350 patients, 97 underwent haemodynamic investigation before sclerotherapy. This group consisted of seven patients with sclerotherapy resistant varices and 90 patients with non-resistant varices. Portal pressure, assessed by portal venous pressure gradient, was similar in these two groups (21.5±4.8 vs 19.8±5.0 mmHg, respectively; NS). However, the prevalence of the 'pipe-line' form of variceal feeding pattern (a large dilated left gastric vein running up the oesophagus) was higher in patients with resistant varices than in those with non-resistant varices (100 vs 3%, respectively; P <0.01) and the diameter of the left gastric vein was larger in patients with resistant varices than in those with non-resistant varices (12.4±2.0 vs 7.8±2.3 mm, respectively; P <0.01). Moreover, the extravariceal portosystemic shunt was poorly developed in patients with resistant varices compared with non-resistant varices (0 vs 52%, respectively; P <0.05). We conclude that the pipe-line pattern, fed by a large left gastric vein and associated with poorly developed extravariceal portosystemic shunt, is a distinctive portal venographic feature of sclerotherapy resistant varices.