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Diagnosis of arrhythmic disorders is challenging because of their short-lasting, intermittent character. Conventional technologies of noninvasive ambulatory rhythm monitoring are limited by modest sensitivity. We present a novel form of wearable electrocardiogram (ECG) sensors providing an alternative tool for long-term rhythm monitoring with the potential of increased sensitivity to detect intermittent or subclinical arrhythmia. The objective was to assess the signal quality and R-R coverage of a wearable ECG sensor system compared to a standard 3-lead Holter. In this phase-1 trial, healthy individuals underwent 24-h simultaneous rhythm monitoring using the OMsignal system together with a 3-lead Holter recording. The OMsignal system consists of a garment (bra or shirt) with integrated sensors recording a single-lead ECG and an acquisition module for data storage and processing. Head-to-head signal quality was assessed regarding adequate P-QRS-T distinction and was performed by three electrophysiologists blinded to the recording technology. The accuracy of signal coverage was assessed using Bland-Altman analysis. Fifteen individuals underwent simultaneous 24-h recording. Signal quality and accuracy of the OMgaments was equivalent to Holter-monitoring (84% vs. 93% electrophysiologists rating, p = 0.06). Signal coverage of R-R intervals showed a very close overlay between the OMsignal system and Holter signals, mean difference in heart rate of 2 ± 5 bpm. The noise level of OMgarments was comparable to Holter recording. OMgarments provide high signal quality for adequate rhythm analysis, representing a promising novel technology for long-term non-invasive ECG monitoring.

Twiddler syndrome is an uncommon yet dangerous phenomenon usually resulting in lead displacement with loss of capture of cardiac implantable electronic devices. In this case report, we present an interesting case of Twiddler syndrome without lead dislodgment which was detected by an alert triggered by an increase in impedance on remote monitoring.

In patients with ischemic cardiomyopathy and an implantable cardioverter–defibrillator who had ventricular tachycardia, catheter ablation was associated with a lower rate of death, ventricular tachycardia storm, or ICD shock at 28 months than an escalation in antiarrhythmic drugs. Ventricular tachycardia caused by the scarring that occurs after myocardial infarction carries a substantial risk of death, a risk that is significantly reduced by the placement of an implantable cardioverter–defibrillator (ICD). 1 ICDs are implanted in more than 100,000 patients annually in the United States. Of these patients, 15% are initially treated with concomitant antiarrhythmic drug (AAD) therapy, 2 and up to 38% receive an appropriate shock for ventricular arrhythmia within 5 years. 3 ICDs effectively terminate ventricular tachycardia, but recurrent arrhythmias and ICD shocks may cause impairment in the quality of life, 4 are associated with an increased risk of death, heart failure, . . .

Purpose Patients undergoing left atrial ablation require transseptal puncture, which can be challenging, even for experienced physicians. This study compared the efficacy and safety of radiofrequency (RF) energy transseptal punctures to conventional approach. Methods Patients requiring transseptal puncture for left atrial access were included using either conventional approach or the NRG™ RF transseptal needle as first attempt. Procedure time for transseptal access, fluoroscopy time, crossover, and safety of both techniques were compared. Results A total of 241 transseptal punctures were performed in 148 consecutive patients (114 men, 54 ± 10 years, left atrial volume 32 ± 10 ml/m 2 ) who underwent 157 procedures with left atrial access, mainly for atrial fibrillation. It was a repeat transseptal procedure in 49 patients. Procedures were guided by transesophageal echocardiography. RF transseptal puncture was planned in 119 procedures. RF was delivered in 98 procedures (82%) for 139/187 punctures: 48 punctures did not require RF, including 25 punctures performed by exposing the needle tip, 22 through patent foramen ovale, and 1 RF delivery failure by the generator. Average time for RF transseptal was 4.8 ± 2.8 min compared to 7.5 ± 8.5 min for conventional approach ( p  = 0.045). Fluoroscopy time was 1.8 ± 1.3 min for RF transseptal and 2.9 ± 2.8 min for standard approach ( p  = 0.043). Four patients required crossover to RF transseptal needle in the conventional group ( p  = 0.003). One tamponade occurred at the end of procedure in a patient using the RF needle, and one interatrial septum dissection with aortic root hematoma occurred in the conventional group. Conclusions Transseptal needle puncture using RF energy can be performed safely and quickly under imaging guidance.

Background and purpose Riata TM defibrillation leads are susceptible to conductor externalization. The point prevalence of insulation defect in Riata TM leads is up to 33 %, but prospective data concerning incidence of new lead abnormalities are lacking. The purpose of our study was to determine the annual incidence of new conductor externalizations and electrical lead failure. Methods A prospective observational study was conducted at a single tertiary center. One hundred forty-one patients were followed over 12 months. A posterior-anterior (PA)/lateral chest x-ray (CXR) with zooming was performed at baseline and at 12 months to screen for conductor externalization. Electrical abnormalities and clinical outcome were also assessed. Results The overall incidence of new insulation defects was 8.5 % at 12 months. High-risk leads for new conductor externalization were lead models 1580, 1582, and 1590 with an annual rate of 11.9, 11.1, and 10 %, respectively. New conductor externalizations were three times more common in 8 Fr leads compared to 7 Fr leads. The overall incidence of new electrical dysfunction was 6.4 % at 12 months. Electrical dysfunction was significantly higher in abnormal leads (25 % [3/12], 4.7 % [6/129]; p  = 0.03) and mostly driven by high ventricular pacing thresholds. There was no difference in inappropriate shock or failure of high-voltage therapy. Conclusion The annual incidence of new insulation defects in Riata TM leads is much higher than previously reported. Lead models 1580, 1582, and 1590 are at highest risk for new conductor externalization. Electrical dysfunction in Riata TM leads is also much higher than reported and is associated with conductor externalization.

Wild brook charr populations (Salvelinus fontinalis) completely introgressed with the mitochondrial genome (mtDNA) of arctic charr (Salvelinus alpinus) are found in several lakes of northeastern Québec, Canada. Mitochondrial respiratory enzymes of these populations are thus encoded by their own nuclear DNA and by arctic charr mtDNA. In the present study we performed a comparative sequence analysis of the whole mitochondrial genome of both brook and arctic charr to identify the distribution of mutational differences across these two genomes. This analysis revealed 47 amino acid replacements, 45 of which were confined to subunits of the NADH dehydrogenase complex (Complex I), one in the cox3 gene (Complex IV), and one in the atp8 gene (Complex V). A cladistic approach performed with brook charr, arctic charr, and two other salmonid fishes (rainbow trout [Oncorhynchus mykiss] and Atlantic salmon [Salmo salar]) revealed that only five amino acid replacements were specific to the charr comparison and not shared with the other two salmonids. In addition, five amino acid substitutions localized in the nad2 and nad5 genes denoted negative scores according to the functional properties of amino acids and, therefore, could possibly have an impact on the structure and functional properties of these mitochondrial peptides. The comparison of both brook and arctic charr mtDNA with that of rainbow trout also revealed a relatively constant mutation rate for each specific gene among species, whereas the rate was quite different among genes. This pattern held for both synonymous and nonsynonymous nucleotide positions. These results, therefore, support the hypothesis of selective constraints acting on synonymous codon usage.

Clarke reviews \"Africa: The Art of a Continent\" at London's Royal Academy of Arts, and \"Africa: The Art of a Continent, 100 Works of Power and Beauty\" at New York's Solomon R. Guggenheim Museum.