[Zero-fluoroscopy catheter ablation for idiopathic premature ventricular contractions from the aortic sinus cusp].

OBJECTIVE: To compare the safety, feasibility, and efficacy of a completely nonfluoroscopic approach to radiofrequency catheter ablation (RFCA) using CARTO3 and ablation with conventional fluoroscopic guidance for treatment of idiopathic premature ventricular contractions from the aortic sinus cusp (ASC-PVCs). METHODS: From April 2013 to October 2015, we prospectively enrolled 52 consecutive patients with ASC-PVCs scheduled for either CARTO3 mapping-guided zero-fluoroscopy ablation (group A, n=23) or conventional fluoroscopic ablation (group B, n=29). The success rates, rates of complications, rates of recurrences, number of radiofrequency applications, procedure time, mapping time and fluoroscopy time were compared between the 2 groups. RESULTS: s No significant differences were found in the success rates between the 2 groups [22/23 (96%) vs 24/29 (83%), P=0.21]. No major complications occurred during the procedures in either group. There was no significant difference with regard to the procedure time between the two groups (79.6∓8.8 vs 77.4∓7.2 min, P=0.332). The procedure was completed without any fluoroscopy use in group A, while the mean fluoroscopy time in group B was 23.1∓6.0 min. Group A showed a shorter mapping time than group B (4.3∓1.7 vs 7.8∓2.6 min, P<0.01) with significantly fewer radiofrequency applications (4.8∓1.1 vs 7.9∓3.2, P<0.01). The recurrence rates were comparable between the two groups over a follow-up period of 5 to 20 months. CONCLUSION: Compared with the conventional fluoroscopic technique, the zero-fluoroscopy approach can shorten the total procedure time and the ablation time with significantly reduced RF applications to eliminate ionizing radiation exposure in RFCA. RFCA guided by CARTO3 system without fluoroscopy is feasible, safe, and effective for treatment of ASC-PVCs.

Potential anatomic substrate of peri-atrioventricular nodal atrial tachycardia ablated from the noncoronary sinus of Valsalva.

INTRODUCTION: Although focal atrial tachycardia (AT) is known to sometimes be ablated from the noncoronary aortic cusp (NCC), the electro-anatomic characteristics of NCC-AT are not well known. METHODS: We compared the clinical, 12-lead electrocardiogram (ECG), and transthoracic echocardiogram characteristics of 6 women (median age, 66.5 years) with NCC-AT and 12 age-matched women (median age, 64.0 years) with atrioventricular nodal reentrant tachycardia (AVNRT) as the control group. RESULTS: There was no difference in the prevalence of hypertension between the two groups (67 vs. 33 %, respectively, P = 0.3213). The resting ECG of the NCC-AT group vs. that of the AVNRT group showed a significantly longer PQ interval (170.0 (interquartile range (IQR), 157.5-180.0 ms) vs. 140.0 ms (IQR, 122.5-147.5 ms), P = 0.0010) and leftward shifting of the QRS axis (4° (IQR, -26.0° to 24.0°) vs. 57° (IQR, 43.0-70.2°), P = 0.0087). The upper interventricular septum (IVS) thickness was significantly greater (15.6 (IQR, 11.9-18.7 ms) vs. 11.7 mm (IQR, 10.2-12.9 ms), P = 0.0393), and the angle formed by the aortic roof and IVS (AS angle) was significantly steeper (103.0° (IQR, 94.2-119.2°) vs. 122.5° (IQR, 108.5-128.5°), P = 0.0343) in the NCC-AT group than in the AVNRT group. CONCLUSIONS: Our data suggest that NCC-AT is characterized by a longer atrioventricular (AV) conduction time, steeper AS angle, and thicker IVS than are seen with AVNRT. These electrocardiographic and echocardiographic characteristics from the IVS to the peri-AV nodal regions may have some effect on the development of NCC-AT.

Electrophysiologic characteristics and radiofrequency ablation of focal atrial tachycardia arising from non-coronary sinuses of Valsalva in the aorta.

OBJECTIVES: Focal atrial tachycardia (AT) arising from non-coronary cusp (NCC) is very rare, and the experience in catheter ablation of this kind of tachycardia remains limited. This study describes the electrophysiologic characteristics and radiofrequency ablation of AT arising from NCC. METHODS AND RESULTS: The study population consisted of five consecutive patients (three females and two males; age 37-68 years) with AT arising from NCC. The morphology of P waves was described as positive, negative, isoelectric, or biphasic (positive-negative or negative-positive). The atrial mapping was performed during tachycardia to define the earliest atrial activation site. Mean tachycardia cycle length of AT in five patients was 363 +/- 44 ms. P-wave morphology was predominantly upright or biphasic in lead II, III, and aVF, inverted in aVR. Positive P-wave morphology was seen in lead aVL in all five patients. The precordial leads were negative-positive in V(1) and V(2), negative-positive or positive in lead V(3)-V(5), and positive in lead V(6). All the five patients underwent successful radiofrequency ablation within NCC. During a follow up of > 3 months, no patient presented with a recurrence. CONCLUSIONS: This study demonstrated that mapping and ablation of focal AT arising from NCC is safe and effective. When earliest activation was recorded in the proximal electrode of the His-bundle catheter, but radiofrequency ablation in this region cannot successfully eliminated the tachycardia, the AT should be considered to arise from NCC especially when P-wave morphology was initially negative with a late positive component in right precordial leads, upright or biphasic in inferior leads.