ABSTRACT
BACKGROUND: The presence of Mahaim accessory pathways (MAP) with anterograde decremental conduction is a disorder that leads to antidromic atrioventricular reentrant tachycardia. There are rare reports of cryoablation use in MAP. This study aims at sharing our experience with using cryoablation to treat MAP in children. METHODS: Electrophysiology study and catheter ablation were performed in 14 patients diagnosed with Mahaim tachycardia between January 2010 and December 2013. Cryoablation was used in nine of the cases. A three-dimensional navigation system with surface electrode patches (EnSite System, St. Jude Medical Inc., St. Paul, MN, USA) was used for all procedures. RESULTS: The patients (two girls and seven boys) had a median age of 11.5 years (8-18 years) and a median weight of 67 kg (31-80 kg). Mahaim conduction was localized in the right posterolateral (n = 4), right lateral region (n = 2), right posteroseptal (n = 1), right anterolateral (n = 1), and right anterior (n = 1). A pathway potential was noted in six of nine cases at the tricuspid annulus. Catheter choices and acute success rates were as follows: cryoablation in four (three of four successful), radiofrequency catheter ablation (RFA) and cryoablation in five (successful in four of five). No fluoroscopy was used in six of nine patients. The mean procedure duration was 249 ± 90 minutes. No major complications were observed. The final long-term success rate for cryoablation was seven of nine (78%). CONCLUSIONS: Cryoablation can be used as a reliable and effective alternative to RFA in the treatment of Mahaim accessory conduction pathways in children. Prospective comparative studies are necessary in order to further evaluate the long-term efficacy of this method.
Subject(s)
Accessory Atrioventricular Bundle/surgery , Cryosurgery/methods , Electrophysiologic Techniques, Cardiac , Heart Conduction System/surgery , Pre-Excitation, Mahaim-Type/surgery , Accessory Atrioventricular Bundle/physiopathology , Adolescent , Child , Echocardiography , Electrocardiography, Ambulatory , Female , Fluoroscopy , Heart Conduction System/physiopathology , Humans , Male , Pre-Excitation, Mahaim-Type/physiopathology , Telemetry , Treatment OutcomeABSTRACT
Doxorubicin (DOX) is a chemotherapeutic agent, and is widely used in cancer treatment. The most common side effect of DOX was indicated on cardiovascular system by experimental studies. There are some studies suggesting oxidative stress-induced toxic changes on liver related to DOX administration. The aim of the present study was to evaluate whether antioxidant N-acetylcysteine (NAC) relieves oxidative stress in DOX- induced liver injury in rat. Twenty-four male rats were equally divided into three groups. First group was used as a control. Second group received single dose of DOX. NAC for 10 days was given to constituting the third group after giving one dose of DOX. After 10 days of the experiment, liver tissues were taken from all animals. Lipid peroxidation (LP) levels were higher in the DOX group than in control whereas LP levels were lower in the DOX+NAC group than in control. Vitamin C and vitamin E levels were lower in the DOX group than in control whereas vitamin C and vitamin E levels were higher in the DOX+NAC group than in the DOX group. Reduced glutathione levels were higher in the DOX+NAC group than in control and DOX group. Glutathione peroxidase, vitamin A and ß-carotene values were not changed in the three groups by DOX and NAC administrations. In histopathological evaluation of DOX group, there were mononuclear cell infiltrations, vacuolar degeneration, hepatocytes with basophilic nucleus and sinusoidal dilatations. The findings were totally recovered by NAC administration. In conclusion, N-acetylcysteine induced modulator effects on the doxorubicin-induced hepatoxicity by inhibiting free radical production and supporting the antioxidant vitamin levels.
