Effect of Electroanatomically Guided Versus Conventional Catheter Ablation of Typical Atrial Flutter on the Fluoroscopy Time and Resource Use: A Prospective Randomized Multicenter Study

Aims: Radiofrequency catheter ablation of typical atrial flutter is one of the most frequent indications for catheter ablation in electrophysiology laboratories today. Clinical utility of electroanatomic mapping systems on treatment results and resource utilization compared with conventional ablation has not been systematically investigated in a prospective multicenter study. Methods and Results: In this prospective, randomized multicenter study, the results of catheter ablation to cure typical atrial flutter using conventional ablation strategy were compared with electroanatomically guided mapping and ablation (Carto®). Primary endpoints of the study were procedure duration and fluoroscopy exposure time, secondary endpoints were acute success rate, recurrence rate, and resource utilization. A total of 210 patients (169 men, 41 women, mean age 63 ± 10 years) with documented typical atrial flutter were included in the study. Acute ablation success, that is, demonstration of bidirectional isthmus block, was achieved in 99 of 105 patients (94%) in the electroanatomically guided ablation group and in 102 of 105 patients (97%) in the conventional ablation group (P > 0.05). Total procedure duration was comparable between both study groups (99 ± 57 minutes vs 88 ± 54 minutes, P > 0.05). Fluoroscopy exposure time was significantly shorter in the electroanatomically guided ablation group (7.7 ± 7.3 minutes vs 14.8 ± 11.9 minutes; P < 0.05). Total recurrence rate of typical atrial flutter at 6 months of follow‐up was comparable between the 2 groups (respectively for the CARTO and conventional group 6.6% vs 5.7%, P > 0.05). The material costs per procedure in the electroanatomically guided and conventional groups (NaviStar® DS vs Celsius® DS) was €3035 (USD 3,870) and €2133 (USD 2,720), respectively. Conclusions: This multicenter study documented that cavotricuspid isthmus ablation to cure typical atrial flutter was highly effective and safe, both in the conventional and the electroanatomically guided ablation group. The use of electroanatomical mapping system significantly reduced the fluoroscopy exposure time by almost 50%, however, at the expense of increased cost of the procedure.     

Real‐time PCR on the first galactomannan‐positive serum sample for diagnosing invasive aspergillosis in liver transplant recipients

Abstract: Invasive aspergillosis (IA) is a life‐threatening complication of liver transplantation. Detection of circulating galactomannan (GM) in serum samples is a method to improve the microbiological diagnosis in patients at risk for IA. However, the assay is hampered by false‐positive results. The search for circulating Aspergillus DNA in the first GM‐positive sample could improve the specificity of the test. Among 484 liver transplant recipients followed in a single center over 4 years, 25 patients had at least 1 GM‐positive serum sample. The threshold of GM positivity was a ratio ≥1. These 25 patients were classified by the clinicians as probable IA (n=11), possible IA (n=2), and no IA (n=12) using the EORTC/MSG criteria with blinding to the polymerase chain reaction (PCR) results. After 1 mL aliquots of the first GM‐positive serum sample were thawed, 2 independent DNA extractions were performed using the MagNA Pure Compact apparatus. Real‐time amplification targeted at Aspergillus fumigatus mitochondrial DNA was performed on 10 μL of the final eluate in duplicate in the 2 independent DNA extractions using a LightCycler instrument. A sample was considered positive when the crossing point was ≤43 cycles in at least 2 out of the 4 replicates. Among the 13 probable or possible IA, 8 patients were PCR positive. The other 12 patients who had no IA were all PCR negative. Our data suggest that a concomitant real‐time PCR performed on the first GM‐positive sample improves the specificity of the first GM‐positive assay result.     

3 Tesla MRI‐Detected Brain Lesions after Pulmonary Vein Isolation for Atrial Fibrillation: Results of the MACPAF Study

MRI Results of the MACPAF Study. Background: Left atrial catheter ablation (LACA) is an established therapeutic approach to abolish symptomatic atrial fibrillation (AF). Objective: Based on the prospective MACPAF study (clinicaltrials.gov NCT01061931) we report the rate of ischemic brain lesions postablation and their impact on cognitive function. Methods: Patients with symptomatic paroxysmal AF were randomized to LACA using the Arctic Front® or the HD Mesh Ablator® catheter. All patients underwent brain MRI at 3 Tesla, neurological, and neuropsychological examinations within 48 hours prior and after the ablation procedure. Results: There was no clinically evident stroke in 37 patients (mean age 62.4 ± 8.4 years; 41% female; median CHADS2 score 1 [IQR 0–2]) after LACA but high‐resolution diffusion‐weighted imaging (DWI) detected new ischemic lesions in 15 (41%) patients after LACA. Four (27%) of the HD Mesh Ablator® patients and 11 (50%) of the Arctic Front® patients suffered a silent ischemic lesion (P = 0.19). In these 15 patients, there was a nonsignificant trend toward lower cardiac ejection fraction (P = 0.07) and AF episodes during LACA (P = 0.09), while activated clotting time levels, number of energy applications, periprocedural electrocardioversion or CHADS₂ score had no impact. Lesion volumes varied from 5 to 150 mm³ and 1 to 5 lesions were detected per patient. However, acute brain lesions had no effect on cognitive performance immediately after LACA. Of the DWI lesions postablation 82% were not detectable on FLAIR images 6–9 months postablation. Conclusions: According to 3 Tesla high‐resolution DWI, ischemic brain lesions after LACA were common but not associated with impaired cognitive function after the ablation procedure. (J Cardiovasc Electrophysiol, Vol. 24, pp. 14‐21, January 2013)