New implantable cardiac monitor with three-lead ECG and active noise detection.

BACKGROUND: A new implantable cardiac monitor (BioMonitor, Biotronik) with a continuous remote monitoring option was prospectively implanted in patients with suspected arrhythmias or for therapy control after atrial fibrillation (AF) ablation. A three-lead ECG detection was intended to make the implantation more independent of the implantation site and the electrical heart axis. Because noise is a frequent problem in implantable cardiac monitors, an active noise detection algorithm was implemented. The aim of the trial was to evaluate the clinical performance of the device. METHODS: The device performance was evaluated in a prospective nonrandomized multicenter study with a follow-up of 12 months. Study endpoints were device-related serious adverse events at 3 months, appropriate QRS detection in direct comparison with synchronized Holter ECG recordings, sensitivity and positive predictive value of arrhythmia detection in comparison with Holter ECG and independent of it, and noise burden during the entire follow-up period. RESULTS: The implantation was successful in all 152 patients. Two device-related serious adverse events (pocket infections) occurred by 3 months. The mean QRS amplitude of 0.3 ± 0.2 mV at implantation remained stable over 12 months. QRS sensing performance indicated little over- and undersensing in most patients. More than 80 % of the patients had more than 22 h of noise-free monitoring per day. CONCLUSION: BioMonitor effectively detects patients with bradycardia, tachycardia, AF, or asystole. Active noise detection seems to reduce the transmission of meaningless data without diminishing the positive predictive value of the device.

Single-catheter approach to pulmonary vein reisolation in selected patients : Data from a prospective registry.

BACKGROUND: In addition to different types of single-tip ablation catheters for pulmonary vein (PV) reisolation, a newly developed circular mapping and ablation catheter (nMARQ®) has been available since 2013 and is currently used only in initial PV isolation procedures. In this prospective registry we present feasibility and efficacy data for PV reisolation procedures with a single-catheter approach (nMARQ®) compared with a standard approach using a single-tip ablation catheter and a circular mapping catheter. METHODS: We included 35 carefully selected patients in this prospective registry and assigned them in a 2:1 ratio to undergo either PV reisolation with a single-tip ablation catheter together with a steerable circular mapping catheter (group 1) or with the nMARQ®catheter only (group 2). The recurrence rate was calculated for atrial tachyarrhythmias with a duration of > 30 s during a mean follow-up of 12.7 months. RESULTS: Reisolation of all PVs was achieved in all patients of both groups. In group 2, all gaps could be correctly identified with the nMARQ® catheter. PV isolation was clearly visible on the nMARQ® catheter in all targeted veins. With the nMARQ® catheter the ablation time decreased significantly (6.3 ± 3.0 vs. 18.6 ± 13.9 min, p < 0.05). The recurrence rate of atrial fibrillation did not differ significantly between the two groups (37.5 vs. 45.5 %, p = 0.66). CONCLUSION: In selected patients, a complete PV reisolation procedure is feasible with a singular circular mapping and ablation catheter. The 12-months success rate is comparable to a classic approach with a combination of a single-tip ablation catheter and a circular mapping catheter.

The HATCH and CHA2DS 2-VASc scores. Prognostic value in pulmonary vein isolation.

AIMS: The HATCH score describes the risk of paroxysmal atrial fibrillation (Afib) progression, while the CHA2DS2vasc score depicts the risk of thromboembolic events in patients with Afib. We hypothesized that both scores may predict failure of Afib ablation. METHODS AND RESULTS: In all, 449 consecutive patients (65.5 % male, mean age 61.7 ± 10.1 years) who presented to our institution for Afib ablation were investigated. A HATCH score of 0, 1, 2, 3, and ≥ 4 was found in 19.6, 50.3, 9.8, 15.6, and 4.6 % of the patients, respectively. A CHA2DS2vasc score of 0, 1, 2, 3, 4, 5, and > 5 was found in 10.7, 20.9, 25.1, 20.6, 15.0, 4.7, and 3.0 % of the patients, respectively (mean CHA2DS2vasc score, 2.4 ± 1.5). After 618 procedures (1.38 ± 0.55/patient), 84.3 % of patients were free of any atrial arrhythmia after a mean follow-up of 12.7 ± 7.1 months. The freedom of Afib after a single ablation procedure ranged between 50.7 and 60.3 % in patients with HATCH scores between 0 and 3 and dropped to 30.0 % in patients with a HATCH score greater than 3 (p = 0.041). The freedom of Afib after 1.38 procedures per patient ranged between 79.5 % and 88.4 % in patients with a HATCH score between 0 and 3 and was lower with a score of 4 or more (66.7 %, p = 0.064). Pulmonary vein isolation was equally successful in patients with a CHA2DS2vasc score of 5 or lower, but less effective in patients with a score greater than 5 (p = 0.013). CONCLUSION: Pulmonary vein isolation is equally effective in patients with a low-to-moderate risk of disease progression and thromboembolic risk. However, the success rate seems to decrease in patients with high sores.

Adjunctive surgical atrial fibrillation ablation during cardiac surgery: real life experiences.

AIM: Several tools have been invented for surgical atrial fibrillation (AF) ablation. In this study, we investigated the real world efficacy of intraoperative AF ablation (AFA) with radiofrequency-energy or cryo-ablation and performed an electro-anatomical remap in some patients with recurrences. METHODS: Seventy-three consecutive patients (53 male, median age of 69 ± 7 years) with history of AF underwent cardiac surgery for valve repair (74 % mitral defects, 60 % aortic defects) and/or coronary artery bypass graft procedures (56 %). During a follow-up of 23 ± 11 months after AFA we performed intensified holter-monitoring (4-7 days). Patients with symptomatic relapse of atrial arrhythmias (AA) were offered the opportunity for additional electrophysiological examination (EPE). RESULTS: During 23 ± 11 months after AFA, 45 patients (62 %) had recurrent AA. In eight patients we performed EPE. In all 8 cases, septal circumferential lesions could be demonstrated during mapping with discrete gaps. All lateral veins were isolated however, posteriorly deep inside the vein leaving the antral region completely untreated. Neither roof lines nor mitral isthmus lines were complete. Performing catheter ablation, all veins could be isolated and seven patients were free of any arrhythmias during follow up (9 ± 5 months) without taking antiarrhythmic drugs. CONCLUSION: Surgical AF ablation may often be incomplete rendering sobering results in unselected patients. Completion of the ablation is feasible with catheter ablation with good clinical outcome.

Fibres found in the eye during and after phacoemulsification cataract surgery.

PURPOSE: Fibres are regularly found within the delivery cartridge (DC) and in the anterior chamber (AC) during phacoemulsification cataract surgery (PCS) and postoperatively. The purpose of this study was to identify their frequency and possible significance. SETTING: Dedicated ophthalmic day surgery. DESIGN: Prospective, consecutive, single-surgeon, cohort study. METHODS: In 639 eyes undergoing PCS, the presence of fibres was documented in or on both the DC and in the AC intraoperatively, and in the AC postoperatively. The intraoperative method of fibre removal was documented. Corrected distance visual acuity (CDVA) was recorded preoperatively, and at day 1, week 1, and week 4 postoperatively. The incidence of clinical cystoid macular oedema (CMO) and endophthalmitis in the retained fibre subcohort was compared with that of the non-fibre subcohort. RESULTS: A total of 5.2% of the operated eyes had a fibre or fibres in or on the DC, which in all cases was removed with forceps intraoperatively. A total of 14.6% of operated eyes had a fibre or fibres in the AC intraoperatively; these were removed by irrigation/aspiration. Postoperatively, five eyes (0.78%) had a fibre in the AC. There was no significant difference in postoperative CDVA between the fibre and non-fibre subcohorts (P=0.26), and no clinically significant CMO or endophthalmitis in either subcohort. CONCLUSIONS: Most fibres seen on the DC or in the eye are sterile and non-inflammatory. However, there have been reports of endophthalmitis attributed to retained fibres. In this study, there were no complications attributable to the fibres, but their removal may minimise any adverse potential.

Expression of connexins 40 and 43 in human left atrium in atrial fibrillation of different aetiologies.

OBJECTIVE: To test the hypothesis that atrial fibrillation (AF) is associated with changes in the expression of connexins 40 and 43 in the left atrium with more pronounced changes in mitral valve disease than in lone AF. METHODS: Protein concentrations of connexin 40 and connexin 43 were analysed in left atrial tissue of patients undergoing cardiac surgery. One group of patients had lone AF (n = 41), one group had AF and mitral valve repair (n = 36), and one group in sinus rhythm served as controls (n = 15). RESULTS: Western blot analysis of connexin 40 and connexin 43 expression showed an increase of both gap junctional proteins (connexin 43 > connexin 40) in patients with AF of all forms compared with patients in sinus rhythm (p = 0.01 and p = 0.011, respectively). Subgroup analysis showed increased concentrations of connexin 40 in lone AF and AF with mitral valve disease compared with sinus rhythm (p = 0.06 and p = 0.029, respectively), whereas the same analysis for connexin 43 reached significance only in the mitral valve disease group (p = 0.031). No differences in connexin 40 and connexin 43 expression were detectable between lone AF and AF with mitral valve disease. Within the groups connexin 40 and connexin 43 expression did not differ between patients with paroxysmal AF and patients with chronic AF. CONCLUSION: The present study shows for the first time that AF can induce changes in the left atrium with increased connexin expression. Furthermore, no systematic differences between patients with paroxysmal and chronic AF were detected.

Fibrosis in left atrial tissue of patients with atrial fibrillation with and without underlying mitral valve disease.

OBJECTIVE: To examine the hypothesis that major extracellular matrix (ECM) proteins are expressed differently in the left atrial tissue of patients in sinus rhythm (SR), lone atrial fibrillation (AF), and AF with underlying mitral valve disease (MVD). DESIGN: Case-control study. PATIENTS: 118 patients with lone AF, MVD+AF, and SR. MAIN OUTCOME MEASURES: Collagen I, collagen III, and fibronectin protein expression measured by quantitative western blotting techniques and immunohistochemical methods. RESULTS: Protein concentrations increased in patients with AF (all forms) compared with those in SR (all forms): collagen I (1.15 (0.11) v 0.45 (0.28), respectively; p = 0.002), collagen III (0.74 (0.05) v 0.46 (0.11); p = 0.002, and fibronectin (0.88 (0.06) v 0.62 (0.13); p = 0.08). Especially, collagen I was similarly enhanced in both lone AF (1.49 (0.15) and MVD+AF (1.53 (0.16) compared with SR (0.56 (0.28); both p = 0.01). Collagen III was not significantly increased in lone AF but was significantly increased in AF combined with MVD (0.84 (0.07) both compared with SR (0.46 (0.11); p = 0.01). The concentration of fibronectin was not significantly increased in lone AF and MVD+AF (both compared with SR). Furthermore, there was a similar degree of enhanced collagen expression in paroxysmal AF and chronic AF. CONCLUSIONS: AF is associated with fibrosis. Forms of AF differ from each other in collagen III expression. However, there was no systematic difference in ECM expression between paroxysmal AF and chronic AF. Enhanced concentrations of ECM proteins may have a role in structural remodelling and the pathogenesis of AF as a result of separation of the cells by fibrotic depositions.