[A comparison of two methods of long-term external ECG telemonitoring in patients after ablation for atrial fibrillation]. / Srovnání dvou metod dlouhodobého externího telemonitorování EKG po ablaci fibrilace síní

AIM: The aim of the study was to compare two methods of long-term ECG monitoring after atrial fibrillation (AF) ablation. METHODS: The study included 279 patients with paroxysmal (n = 163) or persistent (n = 116) AF, who were followed up for 1 year after the first catheter ablation for AF. All patients were provided with episodic ECG recorder for 1 year and instructed to send at least 2 random ECG recordings per day and whenever they sensed symptoms. They were also provided with external loop recorder for 2-3 weeks at 6 and 12 months to enable more continuous ECG monitoring. RESULTS: At the end of 39 ± 12 (12-60) month follow-up, 143 (88%) patients with paroxysmal AF, and 105 (91%) patients with persistent AF, respectively, remained in stable sinus rhythm. The efficacy of episodic recorder expressed as a ratio of patients with identified AF/atrial tachycardia (AT) out of all patients with a documented episode of AF/AT was superior to the efficacy of loop recorder. No AF/AT episode was recorded with the loop recorder that was not also documented by the episodic recorder. Of the patients with the AF/AT recurrence detected by the episodic recorder, the arrhythmia was also revealed by the loop recorder in 70% of the patients after paroxysmal AF ablation (p < 0.001), and in 52% of the patients after persistent AF ablation (p = 0.006). Asymptomatic AF/AT was present in 42 (26%) of patients with paroxysmal AF, and in 28 (24%) patients with persistent AF (p = 0.810). From conventional follow-up unexpected and clinically significant episode of AF/AT that required change in therapy was detected in 9 (5.5%) patients after ablation for paroxysmal AF, and in 4 (3.4%) patients after ablation for persistent FS. CONCLUSION: More episodes of AF/AT after ablation were detected by 1-year daily ECG monitoring using episodic recorder as compared to periodic ECG monitoring with loop recorder. Identification of clinically significant episodes of AF/AT unrecognized from conventional follow-up was low.

Magnetic resonance imaging of the rat brain after epileptic seizures--preliminary results.

The magnetic resonance imaging (MRI) of the rat brain after the epilepsy seizures has been performed. As a first step, the model of the kainic acid (KA) induced seizures has been conducted to examine the possibilities of magnetic resonance imaging system kept in disposition. Seven Wistar albino rats, weighing about 300 g, were used in this study. We administered six of them with intraperitoneal injection of 10 mg/kg of KA. The control animal received corresponding volume of the saline. Every animal was examined under systemic anaesthesia induced by an intraperitoneal injection of thiopental sodium approximately 15 minutes before scanning. Diffusion-weighted imaging (DWI) has been used to acquire the coronary scans of the rat brain. The progress of hyper intense signal at the cerebral cortex and amygdale has been observed. Marked asymmetry of the signal intensity between hemispheres has been discovered. Subsequently the experimental model of audiogenic epilepsy will be conducted.

Metropolitan concentration in developing countries.

"We examine the economic, political and cultural determinants of urban concentration in developing countries using a sample of 53 countries. We find that as countries develop, urban concentration, measured as the largest city's share of the population, at first increases and then decreases. We also find that foreign investment influences concentration in a similar way since foreign investors tend to locate in the main city at low levels of development but are willing to locate outside the center in more developed countries. Political and cultural factors such as lack of democracy, government instability and religiously and [ethnically] homogeneous populations all contribute to high levels of urban concentration. For many developing countries these non-economic factors have led to primate cities whose size far exceeds what would be justified by economic considerations." (SUMMARY IN FRE AND GER)