Accuracy of B-type natriuretic peptide levels in the diagnosis of left ventricular dysfunction and heart failure: a systematic review.

OBJECTIVES: To evaluate the accuracy of B-type natriuretic peptide levels (BNP) in the diagnosis of heart failure and left ventricular dysfunction. DATA SOURCES: Electronic search in Medline, Embase, Cochrane Library and Medion database, and hand search of reference lists. REVIEW METHODS: We have included published studies on the accuracy of BNP which had both sufficient information to construct the 2x2 diagnostic cross table and an appropriate spectrum of patients. RESULTS: Fifty five studies (16,730 patients) were analyzed. The main determinants of diagnostic accuracy were the reference standard analyzed (clinical heart failure versus left ventricular dysfunction), and the methodological quality of the study. BNP levels were highly accurate for the diagnosis of clinical heart failure (diagnostic OR=41; 95% CI 23-74). The negative likelihood ratios were homogeneous, and useful for excluding the existence of heart failure (pooled negative likelihood ratio=0.11; 95% CI 0.08-0.16). The studies focused on the identification of left ventricular dysfunction were heterogeneous, with indications of publication bias, and showed less overall diagnostic accuracy than studies focused on heart failure. CONCLUSIONS: BNP levels are useful for ruling out heart failure. The accuracy of BNP for identifying patients with systolic dysfunction is more limited.

[Early invasive strategy in diabetic patients with non-ST-segment elevation acute coronary syndromes]. / Uso de estrategia invasiva precoz en pacientes diabéticos con síndrome coronario agudo sin elevación del ST.

BACKGROUND AND OBJECTIVES: In the management of non-ST-segment elevation acute coronary syndromes (NSTE-ACS), several studies have shown a reduction in mortality with the use of an invasive strategy in high-risk patients, including diabetic patients. Paradoxically, other studies have shown an under-utilization of this invasive strategy in these patients. The aim of this study is to determine the characteristics of patients managed conservatively and identify determinants of the use of invasive or conservative strategy. PATIENTS AND METHODS: Retrospective cohort study conducted in diabetic patients with NSTE-ACS included in the ARIAM-SEMICYUC registry (n=531) in 2010 and 2011. We performed crude and adjusted unconditional logistic regression. RESULTS: We analyzed 531 diabetic patients, 264 (49.7%) of which received invasive strategy. Patients managed conservatively were a subgroup characterized by older age and cardiovascular comorbidity, increased risk of bleeding and the absence of high-risk electrocardiogram (ECG). In diabetic patients with NSTE-ACS, independent predictors associated with conservative strategy were low-risk ECG, initial Killip class>1, high risk of bleeding and pretreatment with clopidogrel. CONCLUSIONS: The fear of bleeding complications or advanced coronary lesions could be the cause of the underutilization of an invasive strategy in diabetic patients with NSTE-ACS.

Acute seizures due to a probable interaction between valproic acid and meropenem.

OBJECTIVE: To report a probable interaction between meropenem and valproic acid that resulted in the development of epileptic seizures. CASE SUMMARY: A 21-year-old woman presented to our emergency department because of a new-onset, generalized tonic-clonic seizure and was admitted to the intensive care unit. Treatment with valproic acid 1000 mg as a continuous intravenous infusion over 24 hours was initiated. On day 6, the serum concentration of valproic acid was 52.5 microg/mL. On day 13, treatment with intravenous meropenem 1 g 3 times daily was started. On day 15, when the patient was afebrile, numerous myoclonic episodes occurred involving her arms and face; the serum concentration of valproic acid at that time was 42 mug/mL. The valproic acid dose was increased to 2880 mg. Two days later, a generalized tonic-clonic seizure occurred despite the increased dosage, and the plasma concentration of valproic acid fell to 7 microg/mL. The valproic acid dose was increased the following day to 3600 mg; however, the serum concentrations remained <10 microg/mL. On day 19, based on the results of a blood culture and the suspicion of an interaction between meropenem and valproic acid, meropenem therapy was suspended. The serum concentration of valproic acid was 52.4 microg/mL on day 27. Three days later, the patient was asymptomatic and was discharged. DISCUSSION: Coadministration of valproic acid and other drugs that are metabolized by the hepatic cytochrome P450 isoenzyme system can lead to clinically relevant interactions by induction or inhibition of enzymes in shared metabolic pathways. In view of studies in experimental models, the interaction between carbapenem antibiotics and valproic acid is at least possible. Use of the Naranjo probability scale indicated a probable relationship between acute seizures and a meropenem-valproic acid interaction in this patient. CONCLUSIONS: This case report provides strong evidence for an interaction between valproic acid and meropenem. Clinicians should be aware of this potential interaction that may be associated with a serious adverse effect as the result of the decrease of the valproic acid serum concentrations.

Uso de estrategia invasiva precoz en pacientes diabéticos con síndrome coronario agudo sin elevación del ST / Early invasive strategy in diabetic patients with non-ST-segment elevation acute coronary syndromes

Fundamento y objetivos: La estrategia invasiva reduce la mortalidad de los pacientes con síndrome coronario agudo sin elevación del ST (SCASEST) de alto riesgo, entre los que se incluyen los pacientes diabéticos. Sin embargo, diversas publicaciones han puesto de manifiesto una infrautilización de esta estrategia invasiva en estos pacientes. El objetivo de este estudio es conocer las características de los pacientes diabéticos que se tratan de forma conservadora, e identificar determinantes del uso de una u otra estrategia. Paciente y métodos: Estudio de cohortes retrospectivo, realizado en diabéticos con SCASEST incluidos en los cortes anuales de 2010 y 2011 en el registro ARIAM-SEMICYUC. Se realizó un análisis bruto y ajustado mediante regresión logística no condicional. Resultados: Se han analizado 531 pacientes diabéticos, de los cuales 264 (49,7%) recibieron estrategia invasiva. Los pacientes diabéticos que se tratan de forma conservadora son un subgrupo caracterizado por su mayor edad y comorbilidad cardiovascular, mayor riesgo hemorrágico y ausencia de electrocardiograma (ECG) de alto riesgo. Se identifican como variables predictoras independientes asociadas al tratamiento conservador, el ECG de bajo riesgo, el Killip al ingreso superior a 1, alto riesgo hemorrágico y el tratamiento previo con clopidogrel. Conclusiones: El temor a las complicaciones hemorrágicas o la presencia de lesiones coronarias avanzadas podrían ser la causa de la infrautilización de la estrategia invasiva en los pacientes diabéticos con SCASEST (AU)

Background and objectives In the management of non-ST-segment elevation acute coronary syndromes (NSTE-ACS), several studies have shown a reduction in mortality with the use of an invasive strategy in high-risk patients, including diabetic patients. Paradoxically, other studies have shown an under-utilization of this invasive strategy in these patients. The aim of this study is to determine the characteristics of patients managed conservatively and identify determinants of the use of invasive or conservative strategy. Patients and Methods Retrospective cohort study conducted in diabetic patients with NSTE-ACS included in the ARIAM-SEMICYUC registry (n = 531) in 2010 and 2011. We performed crude and adjusted unconditional logistic regression. Results We analyzed 531 diabetic patients, 264 (49.7%) of which received invasive strategy. Patients managed conservatively were a subgroup characterized by older age and cardiovascular comorbidity, increased risk of bleeding and the absence of high-risk electrocardiogram (ECG). In diabetic patients with NSTE-ACS, independent predictors associated with conservative strategy were low-risk ECG, initial Killip class > 1, high risk of bleeding and pretreatment with clopidogrel. Conclusions The fear of bleeding complications or advanced coronary lesions could be the cause of the underutilization of an invasive strategy in diabetic patients with NSTE-ACS (AU)