Objective To characterize the electroanatomical mapping and to assess the value of radiofrequency ablation of atrial tachycardia (AT) in left atria. Methods Nine patients with AT in left atria were studied. Three-dimensional electroanatomical maps were constructed in left atrium using electroanatomical mapping system (Carto). The type of AT (focal or macroreentrant) was identified by the electroanatomical maps, and the ablation targets were at the earliest activation sites or the isthmus of circuit. Results There were ten ATs in 9 cases. The relatively early A waves were recorded in middle, distal or proximal parts of coronary sinus catheter. Nine focal ATs were diagnosed. The activation maps demonstrated that the earliest activation sites were at the ostium of pulmonary veins ( n =5), posterior area of left atrium ( n =2), ostia of left atria appendage ( n =1) or left atria appendage ( n =1) respectively. One macroreeentrant AT was diagnosed, whose circuit propagated through the isthmus, formed by the right superior pulmonary vein and fossa ovalis. Eight focal ATs were all ablated successfully at the earliest activation sites, and one AT from left atria appendage was ablated unsuccessfully. Line of ablation was performed at the isthmus of the macroreentrant AT. During a period of 6-30 months follow-up, one patient with focal AT recurred and underwent another ablation with successful result. No complication occurred. The procedure time and the fluoroscopic time were 90-140 min, 8-16 min respectively in successful cases. Conclusion These results suggest that electroanatomical mapping of AT in left atria may facilitate rapid and accurate identification of the type of AT and guide ablation safely or effectively with less fluoroscopic time and higher success rate, especially in unsuccessful cases with conventional technique.

Objective To investigate the influence of hepatitis B virus (HBV) infection on efficacy of combined antiretroviral therapy (cART) in patients with acquired immunodeficiency syndrome (AIDS).Methods Seventy-eight subjects with human immunodeficiency virus (HIV)/HBV co-infection and 156 subjects with HIV mono-infection were included.CD4+ T cell count,HIV viral load,HBV-markers and liver functions were routinely tested.The differences in survival rate,as well as immunological and virological responses between the two groups (HIV/HBV co-infection group and HIV mono-infection group) during cART were compared.Categorical data were compared by Chisquare test,measurement data were compared by t test,and measurement data with abnormal distribution were compared by Mann-Whitney test.Results At month 42 of cART,HIV RNA levels and CD4+ T cell counts of the two groups were comparable.However,at month 48,54 and 60 of cART,the immunological and virological responses of HIV/HBV co-infection group were less favorable than those of HIV mono-infection group.At each time point of month 12,24,36,48 and 60 of cART,3 out of 13 subjects with HIV/HBV co-infection maintained hepatitis B e antigen (HBeAg)loss; the HBeAg seroconversion rates were 32.1％ (9/28),50.0％ (14/28),53.6％ (15/28),64.3％ (18/28) and 71.4％ (20/28),respectively (x2 =10.189,P=0.037) ; HBV DNA negative rates were 95.1％ (39/41),82.9％ (34/41),68.3％ (28/41),43.9％ (18/41) and 43.9％ (18/41),respectively (x2 =29.982,P=0.000); liver dysfunction rate was 32.1 ％ (25/78),51.4％ (38/74),33.8％ (22/65),47.9％ (23/48) and 6.7％ (3/45),respectively (x2 =28.053,P=0.000).Mortalities in HIV/HBV co-infected and HIV mono-infected individuals were 24.4％ (19/78) and 5.1 ％ (8/156),respectively (x2 =18.841,P＜0.01).Sixteen out of the 19 deaths (84.2 ％) in HIV/ HBV co-infected subjects died of end stage liver diseases.Conclusions HBV co-infection diminishes the long term efficacy of cART.End stage liver diseases are the primary cause of death in HIV/HBV co-infected subjects during cART.