Uric acid significantly correlates with the presence of low-voltage areas at the endocardial mapping in patients with non-valvular atrial fibrillation.

BACKGROUND AND AIMS: Interest in the role of atrial substrate in maintaining Atrial Fibrillation (AF) is growing. Fibrosis is the culprit in the electrical derangement of the myocytes. Many cardiovascular risk factors are known to be linked to atrial scarring; among them Uric Acid (UA) is emerging. The purpose of our study is to find whether UA is associated with Left Atrium (LA) with pathological substrate. METHODS AND RESULTS: 81 patients who underwent radiofrequency transcatheter ablation for nonvalvular AF at the cardiological department of the Niguarda Hospital were enrolled in an observational, cross-sectional, single-center study. UA levels were analysed before the procedure. High density electroanatomic mapping of the LA was performed and patients were divided according to the presence or not of areas of pathological substrate (bipolar voltage <0.5 mV in sinus rhythm). 19 patients showed a LA with pathological substrate. These subjects showed a significant higher prevalence of persistent phenotype of AF (84.2 vs. 25.8%, p < 0.001). UA levels were significantly higher in the group of patients with LA with pathological substrate (6.8 ± 1.9 vs 5.3 ± 1.4 mg/dL, p < 0.001) as well as the prevalence of hyperuricemia (26.5 vs. 6.5%, p = 0.021). The association between uric acid LA with pathological substrate remains significant even after correction for confounding factors (age, left ventricular dysfunction, valvular disease, arrythmia phenotype and furosemide use) and also when the ratio UA/creatinine was evaluated. CONCLUSIONS: In a population of patients who underwent AF ablation, higher UA levels were significantly associated with pathological LA substrate at electro-anatomical mapping.

Direct anchoring technique for pacing and defibrillation leads inserted through cephalic vein: insight for a single high-volume center.

BACKGROUND: Direct anchoring of PM and ICD leads over cephalic vein body is officially discouraged by manufactures due to a supposed risk of conductor fracture or insulation failure, however careful tightening of anchoring knots can probably prevent lead damage. Direct anchoring (DA) technique is routinely used in our center for all leads inserted by cephalic vein while standard anchoring sleeves are used to secure subclavian leads only. Aim of the study is to assess short- and long-term safety of cephalic direct anchoring technique. METHODS: All patients undergoing PM and ICD implantation in our center from November 2014 to March 2016 were consecutively enrolled. Primary endpoints were acute lead fracture, lead dislodgement and chronic lead failure. Secondary endpoint was a composite of short-term surgical complications (pocket hematoma, pneumothorax, and pericardial effusion) plus device infections. Subclavian leads secured with sleeve anchoring (SA) were used as control. RESULTS: A total of 550 leads were implanted in 310 consecutive patients. DA involved 323 leads (59%) while SA was used for 227 (41%). Median follow-up was 50 months (IQR 24-62 months). 17 lead malfunctions (3.1%) were observed during follow-up. No difference was observed between groups (10 DA vs. 7 SP, P=ns). Survival analysis found no difference between groups. Secondary endpoints were not statistically different between groups (5 vs. 1, P=0.08). CONCLUSIONS: Direct anchoring technique of PM and ICD leads is a safe technique and does not increase lead malfunction risk.