Efficacy of radiofrequency ablation for control of intraatrial reentrant tachycardia in patients with congenital heart disease

BACKGROUND: Intraatrial reentrant tachycardia (IART) is a common problem in patients with congenital heart disease (CHD). The progression of clinical symptoms of IART and their response to radiofrequency (RF) ablation are not yet well described. OBJECTIVES: The objective of the study was to determine the early and midterm success rates of RF ablation in effecting a reduction of clinical arrhythmic events in patients with IART and CHD. METHODS: Clinical records of patients undergoing early, successful RF ablation were analyzed retrospectively to document the occurrence and frequency of documented IART, cardioversion and arrhythmia-related hospital visits before and after ablation. RESULTS: Fifty-five catheterizations for intended RF ablation of IART were performed in 45 patients (mean [+/-SD] age 24.5 +/- 10.5 years, 40 after surgical palliation of CHD). Early success was achieved for one or more IART circuits in 33 patients (73%). Mean clinical follow-up of those patients with successful ablation is 17.4 +/- 11.3 months (total 574 patient-months). Documented IART recurrence was noted after 21 (53%) of 40 early, successful catheterizations in 17 (52%) of 33 patients, with a mean time to recurrence of 4.1 months, often with electrocardiographically novel configurations. A more prolonged and frequent history of IART was a univariate risk factor for recurrence. Seven patients underwent repeat RF ablations, and eight patients were restarted on antiarrhythmic medications after ablation. Two patients who had severe ventricular dysfunction before RF ablation died 1.5 and 11 months after RF ablation without known arrhythmia recurrence. Clinical events related to IART increased steadily in frequency for 24 months before RF ablation. Radiofrequency ablation resulted in a reduction of event frequency to levels significantly lower than those in the 12-month period before RF ablation and not significantly different from those levels observed at baseline 3 to 4 years before RF ablation. CONCLUSIONS: In patients with successful RF ablation, the frequency of subsequent events was reduced compared with the 2 preceding years. However, recurrence of IART in patients who showed clinical improvement was frequent, and often revealed the presence of new IART configurations.     

Neurophysiological evaluation with multimodality evoked potentials in craniostenosis and craniofacial stenosis

OBJECTIVE: To observe the changes of gastric mucosal hemodynamics and discuss the possible regulatory factors of prehepatic portal hypertensive rat. METHOD: Prehepatic portal hypertensive (PHT) rat model was produced by various degree of portal vein constriction, and gastric mucosal hemodynamics was measured by radioactive microsphere technique. Statistical analysis was performed by ANOVA, the student t test, and linear correlation. RESULT: The gastric mucosal blood flow was significantly reduced in PHT rats, whereas the blood flow in submucosa, muscular layer prominently increased. The resistance of mucosal vasculature was elevated in PHT rats, however, that of submucosa and muscular layer was decreased remarkably. There was a negative correlation between the gastric mucosal blood flow and portal pressure. CONCLUSION: The gastric mucosa of prehepatic portal hypertensive rat model is poorly perfused prominently. It may be due to the increased mucosal vascular resistance and elevated portal pressure.     

Sound damage and gentamicin treatment produce different patterns of damage to the efferent innervation of the chick cochlea

Both sound exposure and gentamicin treatment cause damage to sensory hair cells in the peripheral chick auditory organ, the basilar papilla. This induces a regeneration response which replaces hair cells and restores auditory function. Since functional recovery requires the re-establishment of connections between regenerated hair cells and the central nervous system, we have investigated the effects of sound damage and gentamicin treatment on the neuronal elements within the cochlea. Whole-mount preparations of basilar papillae were labeled with phalloidin to label the actin cytoskeleton and antibodies to neurofilaments, choline acetyltransferase, and synapsin to label neurons; and examined by confocal laser scanning microscopy. When chicks are treated with gentamicin or exposed to acoustic overstimulation, the transverse nerve fibers show no changes from normal cochleae assayed in parallel. Efferent nerve terminals, however, disappear from areas depleted of hair cells following acoustic trauma. In contrast, efferent nerve endings are still present in the areas of hair cell loss following gentamicin treatment, although their morphological appearance is greatly altered. These differences in the response of efferent nerve terminals to sound exposure versus gentamicin treatment may account, at least in part, for the discrepancies reported in the time of recovery of auditory function.     

IgG antibodies to chlamydial and mycoplasma infection plus C-reactive protein related to poor outcome in unstable angina

This postal survey among 174 UK palliative physicians, aimed to assess current practice and perceived problems within the management of venous thromboembolism (VTE) in patients with advanced cancer. The questionnaire was returned by 131 out of 174 (74%) of the doctors surveyed. The most common estimated incidence of patients with VTE was 1-5%. The diagnosis of VTE is usually confirmed by further investigation and in general, outpatients are more likely to be anticoagulated than inpatients. Problems with anticoagulation include bleeding, international normalized ratio instability, appropriateness of anticoagulation, practical difficulties associated with monitoring, and recurrent VTE. Although probably less effective, 77 out of 128 (60%) of respondents use subtherapeutic regimes in order to minimize the risks. Patients with advanced malignancy and VTE are anticoagulated, if considered appropriate, by the vast majority of palliative physicians in the UK. Warfarin has been abandoned in favour of low-molecular-weight heparin (LMWH) by 26%. LMWH provides anticoagulation with no need for monitoring, has no significant drug interactions and is not affected by liver dysfunction. Theoretically, LMWH is more effective than warfarin in the secondary prevention of VTE with less risk of bleeding.     

Allergenic sesquiterpene lactones from Eupatorium cannabinum L. and Kaunia rufescens (Lund ex de Candolle)

From Eupatorium cannabinum L., a hitherto unknown alpha-methylene-gamma-butyrolactone, 3 beta-peroxyeucannabinolide, was isolated. This compound and eupatoriopicrin from the same plant showed a weak sensitizing capacity in guinea pigs. 2-oxoludartin and dehydroleucodin, isolated from Kaunia rufescens (syn. Eupatorium rufescens), were strong sensitizers in the same sensitizarian procedure.     

The prediction of risk of recurrence and time to recurrence of hepatocellular carcinoma after orthotopic liver transplantation: a pilot study

Orthotopic liver transplantation (OLTx) in the presence of hepatocellular carcinoma (HCC) has been complicated by high recurrence rates. The ability to determine the risk and timing of HCC recurrence on an individual basis would greatly aid in the candidate selection process resulting in a more efficient use of donated organs and allow the individualization and better evaluation of adjuvant chemotherapy. The 214 patients who underwent OLTx in the presence of HCC were analyzed. From the 178 patients who survived more than 150 days, 71 (40%) have suffered HCC recurrence. Based on five risk factors, that is, gender, tumor number, lobar tumor distribution, tumor size, grade of vascular invasion, artificial neural network models predicting the likelihood of HCC recurrence within 1, 2, and 3 consecutive years after transplantation were developed. Based on model predictions, those combinations of risk factors that should/should not lead to recurrence were generated, allowing stratification of patients into the following three groups: 1) patients who should not suffer HCC recurrence and who should not need adjuvant therapy, 2) patients who will suffer recurrence and for whom postoperative chemotherapy significantly prolonged survival (but did not prevent recurrence), and 3) patients who may or may not suffer HCC recurrence and whose recurrence may be prevented by adjuvant chemotherapy. The outcome of OLTx for patients with HCC can be prognosticated based on a number of clinical variables. If verified through multicenter trials, these models could be made available to transplantation programs performing OLTx in the presence of HCC.