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Objectives: Clinical success of atrial fibrillation (AF) ablation depends on persistent blocking of electrical conduction across the ablation lines. Epicor high-intensity focused ultrasound (HIFU) ablation has been credited with a variable clinical efficacy. The aim of this work is to ascertain the electrophysiological (EP) efficacy of such lesions, by assessing pulmonary vein isolation (PVI) after open chest HIFU ablation, in the clinical setting., Methods: Ten consecutive mitral patients (mean age: 57±10 years) with paroxysmal AF undergoing concomitant ablation with the Epicor ablation system (St. Jude Inc.®, Minneapolis, MN, USA) were enrolled for EP assessment. During surgery, pairs of additional temporary wires were positioned on the right PVs (RPVs) and on the roof of the left atrium (RLA), before epicardial ablation. Exit block (no capture during PV pacing) of RPV and of RLA was assessed before, after ablating and immediately after closure of the chest, in order to check the correct positioning of the wires. EP assessment was repeated before discharge and at 3 weeks., Results: Baseline RPV pacing threshold (PT) was 3.5±2 mA (range 1.5-8), of RLA 1.73±1.1 mA (range 0.7-4.3 mA). PVI was not reached any time after HIFU ablation. At the pre-discharge EP study, the absence of isolation was observed in all cases. At 3 weeks, the PTs were 6.8±5.8 mA on RPV (range 2-16) and 6.4±5.3 mA (range 1-19) on RLA. All patients were discharged in sinus rhythm., Conclusions: PVI was not achieved after Epicor HIFU ablations, up to 3 weeks after surgery.

Introduction: Atrial fibrillation (AF) in mitral regurgitation (MR) is a complex disease where multiple factors may induce left-atrial structural remodeling (SR). We explored the differential SR of the left-atrial posterior wall (LAPW) of patients affected by MR with or without persistent AF, and the expression of key proteins involved in its pathogenesis., Methods and Results: Light microscopy of LAPW samples from 27 patients with MR and persistent AF (group 1), 33 with MR in sinus rhythm (group 2), and 15 autopsy controls (group 3) was used to measure myocyte diameter, percentage of myocytolytic myocytes, interstitial fibrosis, and capillary density; RT-PCR and Western blotting were used to assess the mRNA and protein levels of SOD-1, SOD-2, HO-1, calpain, MMP-2, MMP-9, TIMP-1, TIMP-2, and VEGF; immunofluorescence was used to locate these proteins. Myocyte diameter was similar in groups 1 and 2, but larger than controls. Compared to group 2, group 1 had more myocytolytic myocytes (20.8 ± 5.6% vs 14.7 ± 4.5%; P < 0.0001), increased interstitial fibrosis (10.4 ± 5.1% vs 7.5 ± 4.2%; P < 0.05), and decreased capillary density (923 ± 107 No/mm(2) vs 1,040 ± 100 No/mm(2); P < 0.0001). All of the proteins were more expressed in groups 1 and 2 than in controls. The protein and mRNA levels of SOD-1, SOD-2, MMP-2, and MMP-9 were higher in group 1 than in group 2., Conclusions: The LAPW of MR patients with or without AF shows considerable SR. The former has more severe histopathological changes and higher levels of proteins involved in SR, thereby reaching a threshold beyond which the sinus impulse cannot normally activate atrial myocardium., (© 2011 Wiley Periodicals, Inc.)

Objective: Clinical success of atrial fibrillation ablation depends on persistent transmurality of the lesions. Although bipolar radiofrequency grants acute pulmonary vein isolation, the fate of such ablations in the clinical setting is unknown. We assessed postoperative pulmonary vein isolation up to 3 weeks after open chest bipolar radiofrequency ablation., Methods: Thirteen consecutive patients with mitral valve disease (mean age, 60 +/- 10 years) and atrial fibrillation undergoing concomitant ablation with the BP2 bipolar device (Medtronic, Inc, Minneapolis, Minn) were enrolled for electrophysiologic assessment. During surgery, pairs of additional temporary wires were positioned on the right pulmonary veins and on the roof of the left atrium before bipolar ablation. Entrance block (abatement or disconnection of electrogram potentials) and exit block (no entrainment during pulmonary vein pacing) of the right pulmonary veins and of the free left atrium were assessed before and after ablation. After right pulmonary vein isolation was obtained, one additional encircling line was added. Electrophysiologic assessment was repeated before discharge and at 3 weeks., Results: Baseline right pulmonary vein pacing threshold was 2.9 +/- 1.6 mA. After 3 +/- 1 encircling ablations, bidirectional block was attained in all pulmonary veins. At pre-discharge electrophysiologic study, complete isolation persisted in all cases. At 3 weeks, conduction block persisted in 11 (85%) of 13 patients. All patients were discharged in sinus rhythm. At follow-up (19 +/- 7 months), 12 (92%) of 13 patients were still free from atrial fibrillation., Conclusions: Irrigated bipolar radiofrequency ablation provides acute transmurality after multiple ablations. However, total recovery of conduction occurred in 15% of the patients after 3 weeks. Repeated multiple ablations, possibly complemented by block validation, are suggested to help achieve durable transmurality with such technology., (2010 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.)

Here we report the description of a simple, safe and reproducible technique to perform a complete biatrial set of lines, entailing left and right isthmus lines, using bipolar radiofrequency as a solo modality or in combination with cryoenergy.

The field of information technology and the Internet for health care has developed rapidly in the last few years. Furthermore, new services devoted to improve personalized healthcare are emerging from current web-orientated research. Control of eating and physical activity behaviors can be performed in a computer mediated way as a social networking application. To this purpose, we designed and implemented a web application based on the cooperation between two communities: Patients and Nutritionists. The patients are able to cooperate as within a self-help group, while nutritionists can guide patients struggling with incorrect lifestyle and its consequences.