RESUMO
BACKGROUND: Previous research has demonstrated the prognostic value of echocardiography with tissue Doppler imaging (TDI) in the heart failure (HF) population. Heart rate recovery (HRR) has also recently shown promise as a prognostic marker. HYPOTHESIS: We hypothesize echocardiography with TDI and HRR will be significantly correlated and both will provide prognostic information. METHODS: A total of 243 subjects underwent echocardiography with TDI and maximal exercise testing to determine: (1) the ratio between mitral early (E) to mitral annular (E') and E to mitral late (A) velocity; (2) left ventricular ejection fraction (LVEF); (3) left ventricular (LV) mass; (4) LV end-systolic volume (LVESV); and (5) HRR at 1 minute postexercise (HRR(1)). RESULTS: HRR(1) was significantly correlated with LVEF (r = 0.14, P = .03), LV mass (r = - 0.30, P <.001), E/A (r = - 0.22, P = .001), and E/E' (r = - 0.49, P <.001). Multivariate Cox regression analysis revealed HRR(1) was the strongest predictor of cardiac mortality (chi(2): 55.5, P <.001); LV mass (residual chi(2): 13.1, P <.001), E/E' (residual chi(2): 11.2, P = .001), and LVESV (residual chi(2): 5.9, P = .015) all added significant prognostic value and were retained in the regression while LVEF was removed (residual chi(2): 0.008, P = .93). CONCLUSIONS: To our knowledge, this is the first investigation demonstrating an association between HRR and variables obtained from echocardiography with TDI in subjects with HF. The combination of both assessment techniques provides improved prognostic discrimination.
Assuntos
Ecocardiografia Doppler , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Frequência Cardíaca , Idoso , Distribuição de Qui-Quadrado , Teste de Esforço , Feminino , Insuficiência Cardíaca/mortalidade , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Modelos de Riscos Proporcionais , Recuperação de Função Fisiológica , Medição de Risco , Fatores de Risco , Volume Sistólico , Fatores de Tempo , Função Ventricular EsquerdaRESUMO
BACKGROUND: Cardiopulmonary exercise testing (CPET) in the heart failure population is a standard of care in both American and European clinics, although the mode of exercise typically differs. The purpose of the present study was to compare the prognostic characteristics of peak oxygen consumption (VO2) and the minute ventilation-carbon dioxide production (VE/VCO2) slope between two independent heart failure groups. DESIGN AND METHODS: One hundred and two subjects underwent maximal exercise CPET using bicycle ergometry at San Paolo Hospital in Milan, Italy (SPH) and 105 subjects underwent treadmill CPET at Virginia Commonwealth University in Richmond, Virginia (VCU). Subjects were tracked for cardiac-related mortality for a 1-year period after CPET. RESULTS: There were 13 cardiac-related deaths over the 1-year tracking period in both groups. Optimal prognostic threshold values for peak VO2 were 12.9 ml O2/kg per min (sensitivity 81%, specificity 69%) in the SPH group and 12.0 ml O2/kg per min (sensitivity 74%, specificity 69%) in the VCU group. An optimal prognostic threshold value for the VE/VCO2 slope was 34.4 in the SPH (sensitivity 61%, specificity 85%) and 34.5 in the VCU (sensitivity 64%, specificity 93%) groups. DISCUSSION: The prognostic characteristics of peak VO2 and the VE/VCO2 slope were similar between the two centers. These results suggest that the mode of exercise does not greatly impact the prognostic utility of CPET responses in heart failure. They further suggest that prognostic guidelines for the application of CPET in heart failure may be applied globally, irrespective of differences in testing modality.
