Using high-resolution voltage maps to predict “redo” in the treatment of atrial fibrillation (AF)

The aim of this work is to use biomarkers extracted from high-resolution voltage maps of atrial fibrillation (AF) patients in order to make predictions about future “redo” procedures. We collected maps of the left atrium of 122 patients, prior of being treated for AF The bipolar voltage maps were extracted with the Rythmia system from Boston Scientific and subsequently analyzed in the MATLAB environment. The present study focuses on three biomarkers extracted from those maps. Two are associated with the bipolar voltage measurements on the map, i.e., the mean voltage and the voltage dispersion on the map. The third indicator is the area of the atrium evaluated from the map. The data are used for feeding a supervised classification algorithm. The output variable is a binary variable that is set to 1 if the patient will need a “redo” procedure in the twelve months following the cardiac intervention and 0 otherwise. We show that the biomarkers have some statistical power in predicting future outcomes. Especially the mean voltage on the map is the best predictor of the future outcome. We determine the cutoff value for the mean voltage based on the best prediction accuracy of Vm=0.542 mV in agreement with previous studies. We discuss some extensions of this study that could allow improvements in predictive power.Peer ReviewedPostprint (published version

A comparison of methodologies for pulmonary veins segmentation in high definition voltage maps of patients with atrial fibrillation

This paper compares three methodologies used to seg- ment images extracted from the atria of patients with atrial fibrillation (AF). We collected voltage maps of 120 pa- tients’ left atrium before being treated for AF with tissue ablation. The high-definition voltage maps (HDVM) were extracted with the Rythmia software system from Boston Scientific and subsequently analyzed offline in MATLAB. During the analysis, the atrium is segmented into three main structures: body, pulmonary veins (PVs), and mitral valve (MV). Method I is based on a manual elimination of the PV by the operator. Method II uses a semi-automatic method based on geometric considerations coupled with a thresh- old for voltage value. Method III, in addition, uses geo- metric features, i.e., the geometric curvature, to eliminate the maps’ PVs. We quantitatively compare the two first methods’ effi- ciency and ease of use. In particular, the values of two electrical biomarkers associated with the maps are com- puted before and after the PV’s elimination process. This allows us to classify them according to their sensitivity with respect to the cleaning of the PVs. Finally, we discuss which methodology is more adequate to perform the PVs and MV segmentation in light of im- proving the precision of the resulting maps.Postprint (published version

Associations of hypomagnesemia in patients seeking a first treatment of alcohol use disorder

Introduction: Hypomagnesemia (hypoMg) has not yet been extensively studied in alcohol use disorder (AUD) . We hypothesize that chronic, excessive alcohol consumption favors oxidative stress and pro-inflammatory alterations that may be exacerbated by hypoMg. The objective of this study was to analyze the prevalence and associations of hypoMg in AUD.Patients and Methods: Cross-sectional study in patients admitted for a first treatment of AUD in six tertiary centers between 2013 and 2020. Socio-demographic, alcohol use characteristics, and blood parameters were ascertained at admission.Results: 753 patients (71% men) were eligible; age at admission was 48 years [IQR, 41-56 years]. Prevalence of hypoMg was 11.2%, higher than that observed for hypocalcemia (9.3%), hyponatremia (5.6%), and hypokalemia (2.8%). HypoMg was associated with older age, longer duration of AUD, anemia, higher erythrocyte sedimen-tation rate, gamma-glutamyl transpeptidase, glucose levels, advanced liver fibrosis (FIB-4 >= 3.25) and estimated glomerular filtration rate (eGFR) < 60 mL/min. In multivariate analysis, advanced liver fibrosis (OR, 8.91; 95% CI, 3.3-23.9) and eGFR < 60 mL (OR, 5.2; 95% CI, 1.0-26.2) were the only factors associated with hypoMg.Conclusions: Mg deficiency in AUD is associated with liver damage and glomerular dysfunction suggesting that both comorbidities should be assessed in the course of serum hypoMg

Safety of pulsed field ablation in more than 17,000 patients with atrial fibrillation in the MANIFEST-17K study

Pulsed field ablation (PFA) is an emerging technology for the treatment of atrial fibrillation (AF), for which pre-clinical and early-stage clinical data are suggestive of some degree of preferentiality to myocardial tissue ablation without damage to adjacent structures. Here in the MANIFEST-17K study we assessed the safety of PFA by studying the post-approval use of this treatment modality. Of the 116 centers performing post-approval PFA with a pentaspline catheter, data were received from 106 centers (91.4% participation) regarding 17,642 patients undergoing PFA (mean age 64, 34.7% female, 57.8% paroxysmal AF and 35.2% persistent AF). No esophageal complications, pulmonary vein stenosis or persistent phrenic palsy was reported (transient palsy was reported in 0.06% of patients; 11 of 17,642). Major complications, reported for ~1% of patients (173 of 17,642), were pericardial tamponade (0.36%; 63 of 17,642) and vascular events (0.30%; 53 of 17,642). Stroke was rare (0.12%; 22 of 17,642) and death was even rarer (0.03%; 5 of 17,642). Unexpected complications of PFA were coronary arterial spasm in 0.14% of patients (25 of 17,642) and hemolysis-related acute renal failure necessitating hemodialysis in 0.03% of patients (5 of 17,642). Taken together, these data indicate that PFA demonstrates a favorable safety profile by avoiding much of the collateral damage seen with conventional thermal ablation. PFA has the potential to be transformative for the management of patients with AF.Peer reviewe

Registro Español de Ablación con Catéter. VI Informe Oficial (2006)

Se detallan los resultados del Registro Nacional de Ablación del año 2006, elaborado por la Sección de Electrofisiología y Arritmias de la Sociedad Española de Cardiología. Métodos: Al igual que en anteriores registros, la recogida de datos se llevó a cabo mediante dos sistemas: bien de forma retrospectiva con la cumplimentación de un cuestionario que fue enviado desde la Sección de Electrofisiología y Arritmias a los laboratorios de electrofisiología, bien prospectivamente mediante una base de datos común. La elección de una u otra fue voluntaria por parte de cada uno de los centros. Resultados: En el envío de datos participaron de forma voluntaria 48 centros. El número total de procedimientos de ablación analizado fue 6.568, con una media de 139 ± 75 procedimientos por centro. Como en registros previos, los tres sustratos abordados con mayor frecuencia fueron la taquicardia intranodular (n = 1.881; 28%), las vías accesorias (n = 1.628; 25%) y la ablación del istmo cavotricuspídeo (n = 1.507; 23%). El cuarto sustrato abordado (n = 540; 8%) fue la ablación de fibrilación auricular. El porcentaje general de éxito fue del 92,2%; el de complicaciones mayores, del 1,4%, y el de mortalidad, del 0,015%. Conclusiones: En el registro del año 2006 se mantiene una línea de continuidad ascendente en el número de ablaciones realizadas, con más de 6.500 procedimientos registrados, una elevada tasa de éxito y un número bajo de complicaciones. La ablación de fibrilación auricular supone ya el cuarto sustrato más frecuentemente abordado en las unidades de arritmias de nuestro país