Atrial low voltage areas: A comparison between atrial fibrillation and sinus rhythm.

BACKGROUND: Atrial fibrosis can promote atrial fibrillation (AF). Electroanatomic mapping (EAM) can provide information regarding local voltage abnormalities that may be used as a surrogate marker for fibrosis. Specific voltage cut-off values have been reproduced accurately to identify fibrosis in the ventricles, but these values are not well defined in atrial tissue. METHODS: This study is a prospective single-center study. Patients with persistent AF referred for ablation were included. EAM was performed before ablation. We recorded bipolar signals, first in AF and later in sinus rhythm (SR). Two thresholds delimited low-voltage areas (LVA), 0.5 and 0.3 mV. We compared LVA extension between maps in SR and AF in each patient. RESULTS: A total of 23 patients were included in the study. The percentage of points with voltage lower than 0.5 mV and 0.3 mV was significantly higher in maps in AF compared with maps in SR: 38.2% of points < 0.5 mV in AF vs. 22.9% in SR (p < 0.001); 22.3% of points < 0.3 mV in AF vs. 14% in SR (p < 0.001). Areas with reduced voltage were significantly larger in maps in AF (0.5 mV threshold, mean area in AF 41.3 ± 42.5 cm2 vs. 11.7 ± 17.9 cm2 in SR, p < 0.001; 0.3 mV threshold, mean area in AF 15.6 ± 22.1 cm2 vs. 6.2 ± 11.5 cm2 in SR, p < 0.001). CONCLUSIONS: Using the same voltage thresholds, LVA extension in AF is greater than in SR in patients with persistent AF. These findings provide arguments for defining a different atrial fibrosis threshold based on EAM rhythm.

Evaluación comparativa de cuatro puntuaciones de riesgo para predecir la mortalidad de pacientes con desfibrilador automático implantable en prevención primaria / Comparative evaluation of four risk scores for predicting mortality in patients with implantable cardioverter-defibrillator for primary prevention

Introducción y objetivos: Se han elaborado varias puntuaciones clínicas del riesgo para identificar a los pacientes con un riesgo de mortalidad por cualquier causa elevado a pesar del implante de un desfibrilador implantable. El objetivo de este trabajo es examinar y comparar la capacidad predictiva de 4 sistemas de puntuación sencillos (MADIT-II, FADES, PACE y SHOCKED) por lo que respecta a la predicción de la mortalidad tras implante de desfibrilador para la prevención primaria de la muerte súbita cardiaca en un país mediterráneo. Métodos: Se llevó a cabo un estudio multicéntrico retrospectivo en 15 hospitales españoles. Se incluyó a los pacientes consecutivos remitidos para implante de desfibrilador entre enero de 2010 y diciembre de 2011. Resultados: Se incluyó a 916 pacientes con cardiopatía isquémica o no isquémica (media de edad, 62 ± 11 años; el 81,4% varones). Durante un periodo de 33,4 ± 12,9 meses, fallecieron 113 pacientes (12,3%), el 9,4% (86 pacientes) por causa cardiovascular. A los 12, 24, 36 y 48 meses, la tasa de mortalidad fue del 4,5, el 7,6, el 10,8 y el 12,3% respectivamente. Todas las puntuaciones de riesgo mostraron un aumento escalonado del riesgo de muerte a lo largo de todo el sistema de puntuación de cada una de ellas y las 4 identificaron a los pacientes en mayor riesgo de mortalidad. Las puntuaciones tuvieron asociación significativa con la mortalidad por cualquier causa en todo el periodo de seguimiento. La puntuación PACE fue la que mostró un valor del índice c más bajo, tanto si la población tenía una cardiopatía de origen isquémico (estadístico c = 0,61) como si era de origen no isquémico (estadístico c = 0,61), mientras que la puntuación MADIT-II (estadístico c = 0,67 y 0,65 en la miocardiopatía isquémica y no isquémica respectivamente), las puntuaciones SHOCKED (estadístico c = 0,68 y 0,66 respectivamente) y FADES (estadístico c = 0,66 y 0,60) mostraron unos valores del estadístico c similares (p ≥ 0,09). Conclusiones: En esta cohorte de pacientes mediterráneos que no formaba parte de un ensayo clínico, las 4 puntuaciones de riesgo evaluadas mostraron un significativo aumento escalonado del riesgo de muerte. De entre las puntuaciones de riesgo existentes, MADIT-II, FADES y SHOCKED aportan un rendimiento ligeramente superior al de la puntuación PACE (AU)

Introduction and objectives: Several clinical risk scores have been developed to identify patients at high risk of all-cause mortality despite implantation of an implantable cardioverter-defibrillator. We aimed to examine and compare the predictive capacity of 4 simple scoring systems (MADIT-II, FADES, PACE and SHOCKED) for predicting mortality after defibrillator implantation for primary prevention of sudden cardiac death in a Mediterranean country. Methods: A multicenter retrospective study was performed in 15 Spanish hospitals. Consecutive patients referred for defibrillator implantation between January 2010 and December 2011 were included. Results: A total of 916 patients with ischemic and nonischemic heart disease were included (mean age, 62 ± 11 years, 81.4% male). Over 33.4 ± 12.9 months, 113 (12.3%) patients died (cardiovascular origin in 86 [9.4%] patients). At 12, 24, 36, and 48 months, mortality rates were 4.5%, 7.6%, 10.8%, and 12.3% respectively. All the risk scores showed a stepwise increase in the risk of death throughout the scoring system of each of the scores and all 4 scores identified patients at greater risk of mortality. The scores were significantly associated with all-cause mortality throughout the follow-up period. PACE displayed the lowest c-index value regardless of whether the population had heart disease of ischemic (c-statistic = 0.61) or nonischemic origin (c-statistic = 0.61), whereas MADIT-II (c-statistic = 0.67 and 0.65 in ischemic and nonischemic cardiomyopathy, respectively), SHOCKED (c-statistic = 0.68 and 0.66, respectively), and FADES (c-statistic = 0.66 and 0.60) provided similar c-statistic values (P ≥ .09). Conclusions: In this nontrial-based cohort of Mediterranean patients, the 4 evaluated risk scores showed a significant stepwise increase in the risk of death. Among the currently available risk scores, MADIT-II, FADES, and SHOCKED provide slightly better performance than PACE (AU)

Comparative Evaluation of Four Risk Scores for Predicting Mortality in Patients With Implantable Cardioverter-defibrillator for Primary Prevention.

INTRODUCTION AND OBJECTIVES: Several clinical risk scores have been developed to identify patients at high risk of all-cause mortality despite implantation of an implantable cardioverter-defibrillator. We aimed to examine and compare the predictive capacity of 4 simple scoring systems (MADIT-II, FADES, PACE and SHOCKED) for predicting mortality after defibrillator implantation for primary prevention of sudden cardiac death in a Mediterranean country. METHODS: A multicenter retrospective study was performed in 15 Spanish hospitals. Consecutive patients referred for defibrillator implantation between January 2010 and December 2011 were included. RESULTS: A total of 916 patients with ischemic and nonischemic heart disease were included (mean age, 62 ± 11 years, 81.4% male). Over 33.4 ± 12.9 months, 113 (12.3%) patients died (cardiovascular origin in 86 [9.4%] patients). At 12, 24, 36, and 48 months, mortality rates were 4.5%, 7.6%, 10.8%, and 12.3% respectively. All the risk scores showed a stepwise increase in the risk of death throughout the scoring system of each of the scores and all 4 scores identified patients at greater risk of mortality. The scores were significantly associated with all-cause mortality throughout the follow-up period. PACE displayed the lowest c-index value regardless of whether the population had heart disease of ischemic (c-statistic = 0.61) or nonischemic origin (c-statistic = 0.61), whereas MADIT-II (c-statistic = 0.67 and 0.65 in ischemic and nonischemic cardiomyopathy, respectively), SHOCKED (c-statistic = 0.68 and 0.66, respectively), and FADES (c-statistic = 0.66 and 0.60) provided similar c-statistic values (P ≥ .09). CONCLUSIONS: In this nontrial-based cohort of Mediterranean patients, the 4 evaluated risk scores showed a significant stepwise increase in the risk of death. Among the currently available risk scores, MADIT-II, FADES, and SHOCKED provide slightly better performance than PACE.