Índice cronotrópico y eventos adversos a largo plazo en insuficiencia cardiaca con fracción de eyección conservada / Chronotropic index and long-term outcomes in heart failure with preserved ejection fraction

Introducción y objetivos: Poco se sabe sobre la utilidad de la respuesta de la frecuencia cardiaca (FC) al ejercicio para la estratificación del riesgo en la insuficiencia cardiaca con fracción de eyección conservada (ICFEc). El objetivo de este estudio fue evaluar la asociación entre la respuesta de la FC al ejercicio y el riesgo de episodios de descompensación por insuficiencia cardiaca (DIC) en pacientes sintomáticos estables con ICFEc. Métodos: Se trata de un estudio unicéntrico que incluyó a un total de 133 pacientes con ICFEc (NYHA II-III) tras la realización de una prueba de esfuerzo cardiopulmonar máxima. La respuesta de la FC al ejercicio se evaluó mediante la fórmula del índice cronotrópico (IxC). Para el análisis se utilizó un método de regresión binomial negativa. Resultados: La edad media fue de 73,2±10,5 años, el 56,4% eran mujeres y el 51,1% estaban en fibrilación auricular. La mediana de IxC fue de 0,4 (0,3-0,55). Tras una mediana de seguimiento de 2,4 (1,6-5,3) años, se registraron un total de 146 DIC en 58 pacientes y 41 (30,8%) muertes. El IxC no se asoció con eventos adversos (muerte, p=0,319, y DIC, p=0,573) cuando se analizó de forma conjunta toda la muestra. Sin embargo, se encontró un efecto diferencial en función del ritmo electrocardiográfico para DIC (p para interacción=0,002). El IxC se asoció inversa y linealmente con el riesgo de DIC en aquellos pacientes con ritmo sinusal y de forma lineal y positiva con aquellos en fibrilación auricular. Conclusiones: En pacientes con ICFEc, el IxC se asoció diferencialmente con el riesgo de DIC en función del ritmo electrocardiográfico. Un Ixc más bajo surgió como un factor de riesgo para predecir un mayor riesgo de DIC en pacientes en ritmo sinusal. Por el contrario, un IxC más alto identificó un mayor riesgo en aquellos pacientes en fibrilación auricular. (AU)

Introduction and objectives: Little is known about the usefulness of heart rate (HR) response to exercise for risk stratification in heart failure with preserved ejection fraction (HFpEF). Therefore, this study aimed to assess the association between HR response to exercise and the risk of total episodes of worsening heart failure (WHF) in symptomatic stable patients with HFpEF. Methods: This single-center study included 133 patients with HFpEF (NYHA II-III) who performed maximal cardiopulmonary exercise testing. HR response to exercise was evaluated using the chronotropic index (CIx) formula. A negative binomial regression method was used. Results: The mean age of the sample was 73.2± 10.5 years; 56.4% were female, and 51.1% were in atrial fibrillation. The median for CIx was 0.4 [0.3-0.55]. At a median follow-up of 2.4 [1.6-5.3] years, a total of 146 WHF events in 58 patients and 41 (30.8%) deaths were registered. In the whole sample, CIx was not associated with adverse outcomes (death, P=.319, and WHF events, P=.573). However, we found a differential effect across electrocardiographic rhythms for WHF events (P for interaction=.002). CIx was inversely and linearly associated with the risk of WHF events in patients with sinus rhythm and was positively and linearly associated with those with atrial fibrillation. Conclusions: In patients with HFpEF, CIx was differentially associated with the risk of total WHF events across rhythm status. Lower CIx emerged as a risk factor for predicting higher risk in patients with sinus rhythm. In contrast, higher CIx identified a higher risk in those with atrial fibrillation. (AU)

Chronotropic index and long-term outcomes in heart failure with preserved ejection fraction.

INTRODUCTION AND OBJECTIVES: Little is known about the usefulness of heart rate (HR) response to exercise for risk stratification in heart failure with preserved ejection fraction (HFpEF). Therefore, this study aimed to assess the association between HR response to exercise and the risk of total episodes of worsening heart failure (WHF) in symptomatic stable patients with HFpEF. METHODS: This single-center study included 133 patients with HFpEF (NYHA II-III) who performed maximal cardiopulmonary exercise testing. HR response to exercise was evaluated using the chronotropic index (CIx) formula. A negative binomial regression method was used. RESULTS: The mean age of the sample was 73.2± 10.5 years; 56.4% were female, and 51.1% were in atrial fibrillation. The median for CIx was 0.4 [0.3-0.55]. At a median follow-up of 2.4 [1.6-5.3] years, a total of 146 WHF events in 58 patients and 41 (30.8%) deaths were registered. In the whole sample, CIx was not associated with adverse outcomes (death, P=.319, and WHF events, P=.573). However, we found a differential effect across electrocardiographic rhythms for WHF events (P for interaction=.002). CIx was inversely and linearly associated with the risk of WHF events in patients with sinus rhythm and was positively and linearly associated with those with atrial fibrillation. CONCLUSIONS: In patients with HFpEF, CIx was differentially associated with the risk of total WHF events across rhythm status. Lower CIx emerged as a risk factor for predicting higher risk in patients with sinus rhythm. In contrast, higher CIx identified a higher risk in those with atrial fibrillation.