RESUMEN
PURPOSE: Exercise imaging using current modalities can be challenging. This was patient focused study to establish the feasibility and reproducibility of exercise-cardiovascular magnetic resonance imaging (EX-CMR) acquired during continuous in-scanner exercise in asymptomatic patients with primary mitral regurgitation (MR). METHODS: This was a prospective, feasibility study. Biventricular volumes/function, aortic flow volume, MR volume (MR-Rvol) and regurgitant fraction (MR-RF) were assessed at rest and during low- (Low-EX) and moderate-intensity exercise (Mod-EX) in asymptomatic patients with primary MR. RESULTS: Twenty-five patients completed EX-CMR without complications. Whilst there were no significant changes in the left ventricular (LV) volumes, there was a significant increase in the LVEF (rest 63 ± 5% vs. Mod-EX 68 ± 6%;p = 0.01). There was a significant reduction in the right ventricular (RV) end-systolic volume (rest 68 ml(60-75) vs. Mod-EX 46 ml(39-59);p < 0.001) and a significant increase in the RV ejection fraction (rest 55 ± 5% vs. Mod-EX 65 ± 8%;p < 0.001). Whilst overall, there were no significant group changes in the MR-Rvol and MR-RF, individual responses were variable, with MR-Rvol increasing by ≥ 15 ml in 4(16%) patients and decreasing by ≥ 15 ml in 9(36%) of patients. The intra- and inter-observer reproducibility of LV volumes and aortic flow measurements were excellent, including at Mod-EX. CONCLUSION: EX-CMR is feasible and reproducible in patients with primary MR. During exercise, there is an increase in the LV and RV ejection fraction, reduction in the RV end-systolic volume and a variable response of MR-Rvol and MR-RF. Understanding the individual variability in MR-Rvol and MR-RF during physiological exercise may be clinically important.
Asunto(s)
Prueba de Esfuerzo , Estudios de Factibilidad , Imagen por Resonancia Cinemagnética , Insuficiencia de la Válvula Mitral , Válvula Mitral , Valor Predictivo de las Pruebas , Volumen Sistólico , Función Ventricular Izquierda , Función Ventricular Derecha , Humanos , Masculino , Femenino , Estudios Prospectivos , Insuficiencia de la Válvula Mitral/fisiopatología , Insuficiencia de la Válvula Mitral/diagnóstico por imagen , Reproducibilidad de los Resultados , Persona de Mediana Edad , Anciano , Válvula Mitral/diagnóstico por imagen , Válvula Mitral/fisiopatología , Enfermedades Asintomáticas , Variaciones Dependientes del Observador , AdultoRESUMEN
INTRODUCTION: Diabetes mellitus (DM) is associated with increased risk of hospitalisation in people with heart failure and reduced ejection fraction (HFrEF). However, little is known about the causes of these events. METHODS: Prospective cohort study of 711 people with stable HFrEF. Hospitalisations were categorised by cause as: decompensated heart failure; other cardiovascular; infection or other non-cardiovascular. Rates of hospitalisation and burden of hospitalisation (percentage of follow-up time in hospital) were compared in people with and without DM. RESULTS: After a mean follow-up of 4.0 years, 1568 hospitalisations occurred in the entire cohort. DM (present in 32% [n=224]) was associated with a higher rate (mean 1.07 vs 0.78 per 100 patient-years; p<0.001) and burden (3.4 vs 2.2% of follow-up time; p<0.001) of hospitalisation. Cause-specific analyses revealed increased rate and burden of hospitalisation due to decompensated heart failure, other cardiovascular causes and infection in people with DM, whereas other non-cardiovascular causes were comparable. Infection made the largest contribution to the burden of hospitalisation in people with and without DM. CONCLUSIONS: In people with HFrEF, DM is associated with a greater burden of hospitalisation due to decompensated heart failure, other cardiovascular events and infection, with infection making the largest contribution.