[Troponin-T monitoring in outpatients with nonischemic heart failure]. / Valor de la determinación seriada de troponina T en pacientes ambulatorios con insuficiencia cardiaca no isquémica.

INTRODUCTION AND OBJECTIVE: The usefulness of prolonged troponin-T (TnT) monitoring in outpatients with nonischemic heart failure (HF) is not clear. The aim of this study was to investigate the incidence, prognostic value and determinants of a raised TnT level. METHODS: The study involved 80 outpatients (age 56+/-14 years, 69% male) with chronic stable HF (mean left ventricular ejection fraction 24+/-9%; 51 in New York Heart Association class II and 29 in class III) of non-ischemic origin, as confirmed with coronary angiography. The TnT level was measured at study entry and at every outpatient visit (median interval, 3.1 months; interquartile range [IQR], 1.8-5.0 months) in a follow-up period of 22.2+/-10.6 months. Patients were TnT+ if the level was measurable (i.e., >0.01 ng/mL). RESULTS: At study entry, 7 (9%) patients were TnT+. By 5 years, the cumulative incidence had reached 53%, and the median TnT level was 0.059 ng/mL (IQR, 0.023-0.100 ng/mL; range, 0.013-0.500 ng/mL). Beta-blocker therapy was associated with a reduction in incidence (hazard ratio [HR]=0.220; 95% confidence interval [CI], 0.089-0.540; P=.001) while the incidence increased with the N-terminal probrain natriuretic peptide (NT-proBNP) level (HR=1.005; 95% CI, 1.001-1.010; P=0.021). During follow-up, 14 (17.5%) patients had a cardiac event (i.e., 9 cardiac deaths and 5 urgent transplants); these occurred in 12 (50%) of the 24 TnT+ patients vs. 2 (3.6%) of the 56 TnT- patients (P< .001). After adjustment, Cox multivariate analysis showed that being TnT+ was a predictor of an adverse event (HR per 0.01 ng/mL=1.359; 95% CI, 1.037-1.782; P=.026), independently of the NT-proBNP level (HR per 500 pg/mL=1.057; 95% CI, 1.023-1.092; P=.001). CONCLUSIONS: A measurable TnT level was frequently observed during clinical monitoring of outpatients with non-ischemic HF and indicated a poor prognosis, even when the level was low.

[Prognostic value of BNP and cardiopulmonary exercise testing in patients with systolic heart failure on beta-blocker therapy]. / Valor pronóstico del BNP y la prueba de esfuerzo cardiopulmonar en la insuficiencia cardiaca sistólica en tratamiento con bloqueadores beta.

INTRODUCTION AND OBJECTIVES: The long-term prognostic value of the B-type natriuretic peptide (BNP) level and cardiopulmonary exercise testing in patients with heart failure (HF) who are receiving beta-blocker therapy is not well established. METHODS: The study involved 80 outpatients (78% male, age 50 [11] years) with stable HF, severe systolic dysfunction (left ventricular ejection fraction 25 [9]%), and intermediate functional impairment (New York Heart Association functional class 2.4 [0.6]) who were receiving optimum therapy, including beta-blockers. Their BNP levels (pg/mL) were measured and cardiopulmonary exercise testing was carried out to determine maximal oxygen uptake (VO2max) and ventilatory efficiency (VE/VCO2 slope). Patients were followed up for 2.7 (0.8) years. The study endpoints were cardiovascular death, heart transplantation, and HF hospitalization. RESULTS: The BNP level and VE/VCO2 slope were greater in patients who died (n=7), at 211 pg/mL (51-266 pg/mL) vs. 46 pg/mL (16-105 pg/mL) (P=.017) and 39 (3) vs. 33.8 (5.5) (P=.018), respectively, or who had an adverse event (n=19), at 139 pg/mL (88-286 pg/mL) vs. 40 pg/mL (13-81 pg/mL) (P< .001) and 38.7 (4.3) vs. 32.9 (5.2) (P< .001), respectively. Only the combined endpoint was associated with a significant difference in VO2max (19.7 [5.4] vs. 16.8 [3.9] mL/kg per min, P=.016). On multivariate analysis, BNP >102 pg/mL (P=.002; hazard ratio [HR]=5.2; 95% confidence interval [CI], 1.8-14.8) and VE/VCO2 slope >35 (P=.012; HR =4.3; 95% CI, 1.4-13.2) were the best predictors of an adverse event. In patients who satisfied neither, one or both criteria, 36-month cumulative adverse event rates were 2%, 25% and 63%, respectively (log rank, P< .001). CONCLUSIONS: In ambulatory HF patients with intermediate functional impairment who are receiving optimum beta-blocker therapy, the persistence of a high BNP level (>102 pg/mL) combined with poor ventilatory efficiency (VE/VCO2 slope >35) identify those with a poor long-term prognosis.

Valor pronóstico del BNP y la prueba de esfuerzo cardiopulmonar en la insuficiencia cardiaca sistólica en tratamiento con bloqueadores beta / Prognostic value of BNP and cardiopulmonary exercise testing in patients with systolic heart failure on beta-blocker therapy

Introducción y objetivos. En pacientes con insuficiencia cardiaca y tratamiento con bloqueadores beta, el valor pronóstico a largo plazo del péptido natriurético tipo B (BNP) y la prueba de esfuerzo cardiopulmonar no está bien establecido. Métodos. Se estudió a 80 pacientes ambulatorios con insuficiencia cardiaca estable (el 78% varones; media de edad, 50 ± 11 años), disfunción ventricular severa (FEVI, 25% ± 9%), deterioro funcional intermedio (NYHA, 2,4 ± 0,6) y tratamiento optimizado que incluyera bloqueadores beta. Se midió el BNP (pg/ml) y se realizó una prueba de esfuerzo cardiopulmonar, en la que se midió el consumo máximo de oxígeno (VO2máx) y la ineficiencia ventilatoria (pendiente VE/VCO2). El seguimiento fue de 2,7 ± 0,8 años y se estudió la muerte cardiovascular, el trasplante y el ingreso hospitalario por insuficiencia cardiaca. Resultados. La concentración de BNP y la pendiente VE/VCO2 fueron mayores en los pacientes que fallecieron (n = 7) (211 [51-266] contra 46 [16-105], p = 0,017; 39 ± 3 contra 33,8 ± 5,5, p = 0,018) o presentaron cualquier evento adverso (n = 19) (139 [88-286] contra 40 [13-81], p < 0,001; 38,7 ± 4,3 contra 32,9 ± 5,2, p < 0,001). El VO2máx sólo alcanzó significación para el evento combinado (19,7 ± 5,4 contra 16,8 ± 3,9 ml/kg/min, p = 0,016). Tras el análisis multivariable, el BNP > 102 pg/ml (p = 0,002; hazard ratio [HR] = 5,2; intervalo de confianza [IC] del 95%, 1,8-14,8) y la pendiente VE/VCO2>35 (p = 0,012; HR = 4,3; IC del 95%, 1,4-13,2) fueron los mejores predictores de complicaciones. En presencia de ninguno, alguno o ambos predictores, la incidencia acumulada de eventos a 36 meses fue del 2, el 25 y el 63% respectivamente (log rank < 0,001). Conclusiones. En pacientes con insuficiencia cardiaca, deterioro funcional intermedio y tratamiento optimizado con bloqueadores beta, la persistencia de un BNP elevado (> 102 pg/ml) y la ineficiencia ventilatoria (pendiente VE/VCO2 > 35) identifican a los pacientes con peor pronóstico a largo plazo

Introduction and objectives. The long-term prognostic value of the B-type natriuretic peptide (BNP) level and cardiopulmonary exercise testing in patients with heart failure (HF) who are receiving beta-blocker therapy is not well established. Methods. The study involved 80 outpatients (78% male, age 50 [11] years) with stable HF, severe systolic dysfunction (left ventricular ejection fraction 25 [9]%), and intermediate functional impairment (New York Heart Association functional class 2.4 [0.6]) who were receiving optimum therapy, including beta-blockers. Their BNP levels (pg/mL) were measured and cardiopulmonary exercise testing was carried out to determine maximal oxygen uptake (VO2max) and ventilatory efficiency (VE/VCO2 slope). Patients were followed up for 2.7 (0.8) years. The study endpoints were cardiovascular death, heart transplantation, and HF hospitalization. Results. The BNP level and VE/VCO2 slope were greater in patients who died (n=7), at 211 pg/mL (51­266 pg/mL) vs. 46 pg/mL (16­105 pg/mL) (P=.017) and 39 (3) vs. 33.8 (5.5) (P=.018), respectively, or who had an adverse event (n=19), at 139 pg/mL (88­286 pg/mL) vs. 40 pg/mL (13­81 pg/mL) (P<.001) and 38.7 (4.3) vs. 32.9 (5.2) (P<.001), respectively. Only the combined endpoint was associated with a significant difference in VO2max (19.7 [5.4] vs. 16.8 [3.9] mL/kg per min, P=.016). On multivariate analysis, BNP >102 pg/mL (P=.002; hazard ratio [HR]=5.2; 95% confidence interval [CI], 1.8­14.8) and VE/VCO2 slope >35 (P=.012; HR =4.3; 95% CI, 1.4­13.2) were the best predictors of an adverse event. In patients who satisfied neither, one or both criteria, 36-month cumulative adverse event rates were 2%, 25% and 63%, respectively (log rank, P<.001). Conclusions. In ambulatory HF patients with intermediate functional impairment who are receiving optimum beta-blocker therapy, the persistence of a high BNP level (>102 pg/mL) combined with poor ventilatory efficiency (VE/VCO2 slope >35) identify those with a poor long-term prognosis