RESUMEN
BACKGROUND: Wave reflections, which are increased in patients with heart failure with preserved ejection fraction, impair diastolic function and promote pathologic myocardial remodeling. Organic nitrates reduce wave reflections acutely, but whether this is sustained chronically or affected by hydralazine coadministration is unknown. METHODS AND RESULTS: We randomized 44 patients with heart failure with preserved ejection fraction in a double-blinded fashion to isosorbide dinitrate (ISDN; n=13), ISDN+hydralazine (ISDN+hydral; n=15), or placebo (n=16) for 6 months. The primary end point was the change in reflection magnitude (RM; assessed with arterial tonometry and Doppler echocardiography). Secondary end points included change in left ventricular mass and fibrosis, measured with cardiac magnetic resonance imaging, and the 6-minute walk distance. ISDN reduced aortic characteristic impedance (mean baseline=0.15 [95% CI, 0.14-0.17], 3 months=0.11 [95% CI, 0.10-0.13], 6 months=0.10 [95% CI, 0.08-0.12] mm Hg/mL per second; P=0.003) and forward wave amplitude (Pf, mean baseline=54.8 [95% CI, 47.6-62.0], 3 months=42.2 [95% CI, 33.2-51.3]; 6 months=37.0 [95% CI, 27.2-46.8] mm Hg, P=0.04), but had no effect on RM (P=0.64), left ventricular mass (P=0.33), or fibrosis (P=0.63). ISDN+hydral increased RM (mean baseline=0.39 [95% CI, 0.35-0.43]; 3 months=0.31 [95% CI, 0.25-0.36]; 6 months=0.44 [95% CI, 0.37-0.51], P=0.03), reduced 6-minute walk distance (mean baseline=343.3 [95% CI, 319.2-367.4]; 6 months=277.0 [95% CI, 242.7-311.4] meters, P=0.022), and increased native myocardial T1 (mean baseline=1016.2 [95% CI, 1002.7-1029.7]; 6 months=1054.5 [95% CI, 1036.5-1072.3], P=0.021). A high proportion of patients experienced adverse events with active therapy (ISDN=61.5%, ISDN+hydral=60.0%; placebo=12.5%; P=0.007). CONCLUSIONS: ISDN, with or without hydralazine, does not exert beneficial effects on RM, left ventricular remodeling, or submaximal exercise and is poorly tolerated. ISDN+hydral appears to have deleterious effects on RM, myocardial remodeling, and submaximal exercise. Our findings do not support the routine use of these vasodilators in patients with heart failure with preserved ejection fraction. CLINICAL TRIAL REGISTRATION: URL: www.clinicaltrials.gov. Unique identifier: NCT01516346.
Asunto(s)
Insuficiencia Cardíaca/tratamiento farmacológico , Hidralazina/administración & dosificación , Hipertrofia Ventricular Izquierda/tratamiento farmacológico , Dinitrato de Isosorbide/administración & dosificación , Miocardio/patología , Volumen Sistólico/fisiología , Remodelación Ventricular/efectos de los fármacos , Anciano , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Quimioterapia Combinada , Ecocardiografía Doppler , Femenino , Fibrosis/complicaciones , Fibrosis/tratamiento farmacológico , Fibrosis/fisiopatología , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/fisiopatología , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/fisiopatología , Humanos , Hipertrofia Ventricular Izquierda/complicaciones , Hipertrofia Ventricular Izquierda/fisiopatología , Imagen por Resonancia Cinemagnética , Masculino , Persona de Mediana Edad , Proyectos Piloto , Vasodilatadores/administración & dosificación , Función Ventricular Izquierda/fisiologíaRESUMEN
BACKGROUND: Arterial wave reflections are important determinants of central pressure pulsatility and left ventricular afterload. The augmentation index (AIx) is the most widely used surrogate of arterial wave reflections. Despite multiple cross-sectional studies assessing the correlates of AIx, little prospective data exist regarding changes in AIx over time. We aimed to assess the predictors of changes in AIx over time in adults from the general population. METHODS: We performed radial arterial tonometry assessments a median of 3.18 ± 0.4 years apart on 143 nondiabetic adult participants in the population-based PREVENCION study. Central AIx was obtained using the generalized transfer function of the Sphygmocor device. RESULTS: Predictors of the change in AIx over time were investigated. Among men (n = 67), the change in AIx was predicted by abdominal obesity (standardized ß for waist circumference = 0.34; P = 0.002), impaired fasting glucose (standardized ß = 0.24; P = 0.009), and the change in heart rate (standardized ß = -0.78; P < 0.001). Among women (n = 76), the change in AIx was predicted by non-high-density lipoprotein cholesterol (standardized ß = 0.33; P = 0.001), C-reactive protein levels (standardized ß = 0.24; P = 0.02), change in mean arterial pressure (standardized ß = 0.33; P = 0.001), and change in heart rate (standardized ß = -0.52; P < 0.001). CONCLUSIONS: Metabolic and inflammatory factors predicted changes in AIx over time, with important sex differences. Metabolic factors, such as abdominal obesity and impaired fasting glucose, predicted changes in AIx in men, whereas C-reactive protein and non-high-density lipoprotein cholesterol levels predicted changes in women. Our findings highlight the impact of sex on arterial properties and may guide the design of interventions to favorably impact changes in late systolic pressure augmentation.