ABSTRACT
Objective @# In the present study，the changes of left atrial matrix characteristics and the effect of cathe- ter ablation on cardiac function in elderly patients with persistent atrial fibrillation were observed．Furthermore，the application of two catheter ablation methods including circular pulmonary vein isolation combined with left atrial ma- trix modification or left atrial posterior wall isolation were compared by researchers in order to explore effectiveness and safety of the two methods in elderly persistent atrial fibrillation patients．@*Methods @#A total of 86 elderly pa- tients with persistent atrial fibrillation were selected and divided into two groups using randomization principle ; the pulmonary vein isolation combined with left atrial matrix modified catheter ablation method was named matrix modi- fied group (43 cases) ; the pulmonary vein isolation combined with left atrial posterior wall isolation catheter abla- tion method was named posterior wall isolation group (43 cases) ．During ablation left atrial electro matrix mapping were analyzed by multipole catheter for all patients．After ablation all patients were follow-up in 12 months by car- diac color doppler ultrasound examination，ECG and Holter．The incidence of arrhythmia ，serious adverse event and complications were compared between two groups． Successful rate of single ablation and blank period recur- rence after ablation were observed in 12 months follow-up time. @*Results @#Through electrogram mapping of left atri- um low-voltage areas or scar areas were founded in 72 cases among the 86 cases after ablation，After a 12-month follow-up，the incidence of arrhythmia in the blank period between the two groups was 41．9% ( matrix modified group) and 23. 3% (posterior wall isolation group) ，independently，P＜0. 01，successful rates of single ablation in the two groups were 83. 7% (matrix modified group) ，60. 5% (posterior wall isolation group) ，independently， P ＜0. 01 ．No adverse event occurred in the two groups．After AF ablation LVEF increased，LVEDD and LVAD significantly decreased in all of the cases．There was no significant difference between the two groups in patients ’ characters ablation time and complications rate．@*Conclusion @#Circular pulmonary vein isolation combined with left atrial matrix modification is as safe as left atrial posterior wall isolation，and it is a simplified，personalized，and more effective ablation strategy in elderly patients with persistent atrial fibrillation.
ABSTRACT
The purpose of this study was to compare the pharmacokinetic profiles of tetramethylpyrazine phosphate (TMPP) in plasma and extracellular fluid of the cerebral cortex of rats via three delivery routes: intranasal (i.n.), intragastric (i.g.) and intravenous (i.v.) administration. After i.n., i.g. and i.v. administration of a single-dose at 10 mg/kg, cerebral cortex dialysates and plasma samples drawn from the carotid artery were collected at timed intervals. The concentration of TMPP in the samples was analyzed by HPLC. The area under the concentration-time curve (AUC) and the ratio of the AUCbrain to the AUCplasma (drug targeting efficiency, DTE) was calculated to evaluate the brain targeting efficiency of the drug via these different routes of administration. After i.n. administration, TMPP was rapidly absorbed to reach its peak plasma concentration within 5 min and showed a delayed uptake into cerebral cortex (t max=15 min). The ratio of the AUCbrain dialysates value between i.n. route and i.v. injection was 0.68, which was greater than that obtained after i.g. administration (0.43). The systemic bioavailability obtained with i.n. administration was greater than that obtained by the i.g. route (86.33% vs. 50.39%), whereas the DTE of the nasal route was 78.89%, close to that of oral administration (85.69%). These results indicate that TMPP is rapidly absorbed from the nasal mucosa into the systemic circulation, and then crosses the blood-brain barrier (BBB) to reach the cerebral cortex. Intranasal administration of TMPP could be a promising alternative to intravenous and oral approaches.