Clinical Relevance of Sinus Rhythm Mapping to Quantify Electropathology Related to Atrial Fibrillation

Progression of AF is accompanied by structural and electrical remodelling, resulting in complex electrical conduction disorders. This is defined as electropathology and it increases with the progression of AF. The severity of electropathology, thus, defines the stage of AF and is a major determinant of effectiveness of AF therapy. As specific features of AF-related electropathology are still unknown, it is essential to first quantify the electrophysiological properties of atrial tissue and then to examine the inter- and intra-individual variation during normal sinus rhythm. Comparison of these parameters between patients with and without a history of AF unravels quantified electrophysiological features that are specific to AF patients. This can help to identify patients at risk for early onset or progression of AF. This review summarises current knowledge on quantified features of atrial electrophysiological properties during sinus rhythm and discusses its relevance in identifying AF-related electropathology

Rationale and design of the B-PROOF study, a randomized controlled trial on the effect of supplemental intake of vitamin B12 and folic acid on fracture incidence

Background: Osteoporosis is a major health problem, and the economic burden is expected to rise due to an increase in life expectancy throughout the world. Current observational evidence suggests that an elevated homocysteine concentration and poor vitamin B12and folate status are associated with an increased fracture risk. As vitamin B12and folate intake and status play a large role in homocysteine metabolism, it is hypothesized that supplementation with these B-vitamins will reduce fracture incidence in elderly people with an elevated homocysteine concentration. Methods/Design. The B-PROOF (B-Vitamins for the PRevention Of Osteoporotic Fractures) study is a randomized double-blind placebo-controlled trial. The intervention comprises a period of two years, and includes 2919 subjects, aged 65 years and older, independently living or institutionalized, with an elevated homocysteine concentration ( 12 mol/L). One group receives daily a tablet with 500 g vitamin B12and 400 g folic acid and the other group receives a placebo tablet. In both tablets 15 g (600 IU) vitamin D is included. The primary outcome of the study is osteoporotic fractures. Measurements are performed at baseline and after two years and cover bone health

Effect of magnetic navigation system on procedure times and radiation risk in children undergoing catheter ablation

Transcatheter ablation is an effective method to eliminate the arrhythmogenic substrate in symptomatic children with various types of arrhythmias. A reduction in the procedure and fluoroscopy time would decrease the hazardous effects of the ablation procedures. The magnetic navigation system (MNS) uses atraumatic catheters and facilitates accurate catheter placement in all regions of the heart for mapping and therapy delivery. We compared the efficacy and safety between a manual and MNS-guided approach for mapping and ablation of arrhythmias in a general pediatric arrhythmia population and in a subgroup of young children aged <10 years old. A total of 58 pediatric patients (mean age 12.2 +/- 3.2 years) were included in the present study. Of the 58 consecutive patients, 29 were treated with the MNS and 29 underwent conventional manual ablation. No demographic differences were present between the 2 groups. Acute success was achieved in 26 of 29 patients and 27 of 29 patients (p = NS). The mean procedure and fluoroscopy times were comparable in both study groups (168 +/- 56 minutes vs 183 +/- 52 minutes, p = NS; and 22 +/- 59 minutes vs 30 +/- 29 minutes, p = NS). In young children (aged <10 years), the success rate did not differ between the 2 groups (10 of 11 vs 6 of 8, p = NS). However, significant decreases in the procedure and fluoroscopy times were achieved (139 +/- 57 minutes vs 204 +/- 49 minutes and 13 +/- 7 minutes vs 31 +/- 28 minutes, respectively; p = 0.01 and p = 0.04). In conclusion, our data have strongly suggested that using the MNS for treating young children is advantageous, because it significantly reduced the procedure and fluoroscopy times without compromising efficacy. (C) 2010 Elsevier Inc. All rights reserved. (Am J Cardiol 2010;106:69-72

Outcomes of repeat catheter ablation using magnetic navigation or conventional ablation

After initial catheter ablation, repeat procedures could be necessary. This study evaluates the efficacy of the magnetic navigation system (MNS) in repeat catheter ablation as compared with manual conventional techniques (MANs). The results of 163 repeat ablation procedures were analysed. Ablations were performed either using MNS (n 84) or conventional manual ablation (n 79). Procedures were divided into four groups based on the technique used during the initial and repeat ablation procedure: MANMAN (n 66), MANMNS (n 31), MNSMNS (n 53), and MNSMAN (n 13). Three subgroups were analysed: supraventricular tachycardias (SVTs, n 68), atrial fibrillation (AF, n 67), and ventricular tachycardias (VT, n 28). Recurrences were assessed during 19 11 months follow-up. Overall, repeat procedures using MNS were successful in 89.0 as compared with 96.2 in the MAN group (P ns). The overall recurrence rate was significantly lower using MNS (25.0 vs. 41.4, P 0.045). Acute success and recurrence rates for the MANMAN, MANMNS, MNSMNS, and MNSMAN groups were comparable. For the SVT subgroup a higher acute success rate was achieved using MAN (87.9 vs. 100.0, P 0.049). The use of MNS for SVT is associated with longer procedure times (205 82 vs. 172 69 min, P 0.040). For AF procedure and fluoroscopy times were longer (257 72 vs. 185 64, P 0.001; 59.5 19.3 vs. 41.1 18.3 min, P 0.001). Less fluoroscopy was used for MNS-guided VT procedures (22.8 14.7 vs. 41.2 10.9, P 0.011). Our data suggest that overall MNS is comparable with MAN in acute success after repeat catheter ablation. However, MNS is related to fewer recurrences as compared with MAN

Clinical characteristics and acute results of catheter ablation for outflow tract ventricular tachycardia or premature beats

Contemporary outcome data of catheter ablation for outflow tract tachycardia (OTT) and ventricular premature beats (VPBs) are rare. The aim of this study was to describe the clinical characteristics, the acute procedure success rate, and the long-term survival of patients who underwent an ablation procedure for OTT or VPBs. The study was a single-center retrospective cohort study. All 82 consecutive OTT and VPB first ablation procedures between 1999 and 2009 were included. Patients with structural heart disease were excluded. Mean age was 46 +/- 13 years. Forty-three percent of the patients were male. All patients were alive after a median follow-up duration of 31 months (interquartile range, 14-65 months). Eighty-nine percent suffered from palpitations and 12 % had a history of syncope. Ventricular tachycardia was documented in 73 % and monomorphic VPBs in 99 %. Seventy-three percent of the patients were ablated in the right ventricular outflow tract, 15 % in the left ventricular outflow tract, and 12 % in the coronary cusps. Radiofrequency energy was used in 95 % of the patients, cryo energy in 9 %. Acute success was achieved in 78 %. Six patients (7 %) experienced a complication (five pericardial effusions, one pseudo-aneurysm of the femoral artery). Three patients needed pericardiocentesis (4 %). Ablation for OTT and VPB is successful in the vast majority of cases, with a low but still existing complication rate. Long-term survival was excellent, underscoring the benign nature of this arrhythmia

LEFT ATRIAL APPENDAGE CLOSURE USING LEFT FEMORAL VEIN APPROACH

Atrial Fibrillation (AF) is the most common tachyarrhythmia and is associated with major complications such as thromboembolic events. Anticoagulation therapy remains an important component of AF treatment to avoid thromboembolism. Left Atrial Appendage (LAA) closure may be considered in patients with AF with high stroke risk and contraindications for long term Oral Anti Coagulation (OAC) therapy. Devices for LAA closure are usually placed trans-septally using the Right Femoral Vein (RFV) approach (1). Alternative approaches for accessing the left atrium have been reported. (2) but there are no reports on usage of the Laft Femoral Vein (LFV) for LAA closure by using watchman device, that is unusual for septal puncture(3). In this report, we describe a LAA closure in a 83 year old patient using the LFV approach