Guilherme Garcia

Relation of severe deficiency of vitamin D to cardiovascular mortality during acute coronary syndromes.

Vitamin D deficiency is associated with risk for a first cardiovascular event in the general population, possibly because of inflammation, insulin resistance, and neurohumoral activation. However, its relation with outcomes in acute coronary syndromes has not been reported. To test the hypothesis that severe deficiency of vitamin D is independently associated with cardiovascular mortality during ACS, 206 patients admitted for unstable angina, non-ST-segment elevation myocardial infarction, or ST-segment elevation acute myocardial infarction had 25-hydroxyvitamin D serum levels measured at admission. Severe vitamin D deficiency was defined a priori as a value ≤10 ng/ml. The average concentration of vitamin D was 20 ± 8.2 ng/ml, and 10% of patients were severely deficient (95% confidence interval 6.6% to 15%). Cardiovascular mortality during hospitalization took place in 14 patients, an incidence of 6.8%. Patients with severe vitamin D deficiency had in-hospital cardiovascular mortality of 24%, significantly higher than the 4.9% observed in the remaining patients (relative risk 4.3, 95% confidence interval 1.8 to 10, p = 0.001). After adjustment for Global Registry of Acute Coronary Events (GRACE) score, Gensini angiographic score, and potential confounding variables, severe deficiency of vitamin D remained an independent predictor of in-hospital cardiovascular mortality (odds ratio 14, 95% confidence interval 1.2 to 158, p = 0.03). In conclusion, severe vitamin D deficiency is independently associated with in-hospital cardiovascular mortality in patients with acute coronary syndromes.

Acurácia dos escores GRACE e TIMI na predição da gravidade angiográfica da síndrome coronariana aguda

FUNDAMENTO: A acuracia dos escores GRACE e TIMI em predizer a extensao da doenca coronariana em pacientes com sindromes coronarianas agudas sem supradesnivelamento do segmento ST (SCA) nao esta estabelecida. OBJETIVO: Testar a hipotese de que os escores de risco GRACE e TIMI predizem satisfatoriamente a extensao da doenca coronariana, em pacientes com SCA submetidos a coronariografia. METODOS: Individuos admitidos com criterios objetivos de SCA e que realizaram coronariografia durante o internamento foram consecutivamente analisados. A doenca coronariana angiografica foi descrita de tres formas: quantificacao da extensao da doenca coronariana pelo escore de Gensini; presenca de qualquer obstrucao coronariana (> 70% ou > 50% quando tronco de coronaria esquerda); presenca de doenca severa (triarterial ou tronco de coronaria esquerda). RESULTADOS: Em 112 pacientes avaliados, observou-se correlacao positiva do escore de Gensini com os escores GRACE (p = 0,017) e TIMI (p = 0,02), porem essa associacao foi de fraca magnitude (r = 0,23 e r = 0,27; respectivamente). O escore GRACE nao foi capaz de predizer doenca coronariana obstrutiva (area abaixo da curva ROC = 0,57; 95%IC = 0,46 - 0,69), nem doenca coronariana severa (ROC = 0,59; 95%IC = 0,48 -0,70). O Escore TIMI se mostrou modesto preditor em relacao a presenca de doenca coronariana (ROC = 0,65; 95%IC = 0,55 - 0,76) e presenca de doenca severa (ROC = 0,66; 95%IC = 0,56 - 0,76). CONCLUSAO: (1) Existe associacao positiva entre o valor dos escores TIMI ou GRACE e a extensao da doenca coronaria em pacientes com SCA; (2) No entanto, o grau dessa associacao nao e suficiente para que esses escores sejam preditores acurados dos resultados da coronariografia.

Effectiveness of a myocardial infarction protocol in reducing door-to-ballon time

Background An adequate door-to-balloon time (<120 minutes) is the necessary condition for the efficacy of primary angioplasty in infarction to translate into effectiveness. Objective To describe the effectiveness of a quality of care protocol in reducing the door-to-balloon time. Methods Between May 2010 and August 2012, all individuals undergoing primary angioplasty in our hospital were analyzed. The door time was electronically recorded at the moment the patient took a number to be evaluated in the emergency room, which occurred prior to filling the check-in forms and to the triage. The balloon time was defined as the beginning of artery opening (introduction of the first device). The first 5 months of monitoring corresponded to the period of pre-implementation of the protocol. The protocol comprised the definition of a flowchart of actions from patient arrival at the hospital, the teams awareness raising in relation to the prioritization of time, and provision of a periodic feedback on the results and possible inadequacies. Results A total of 50 individuals were assessed. They were divided into five groups of 10 sequential patients (one group pre-and four groups post-protocol). The door-to-balloon time regarding the 10 cases recorded before protocol implementation was 200 ± 77 minutes. After protocol implementation, there was a progressive reduction of the door-to-balloon time to 142 ± 78 minutes in the first 10 patients, then to 150 ± 50 minutes, 131 ± 37 minutes and, finally, 116 ± 29 minutes in the three sequential groups of 10 patients, respectively. Linear regression between sequential patients and the door-to-balloon time (r = - 0.41) showed a regression coefficient of - 1.74 minutes. Conclusion The protocol implementation proved effective in the reduction of the door-to-balloon time.

Valor prognóstico da troponina I de alta sensibilidade versus troponina T nas síndromes coronarianas agudas

BACKGROUND Despite superior diagnostic accuracy of high-sensitivity cardiac troponins, their prognostic value has not been validated against conventional cardiac troponins. OBJECTIVE To test the prognostic value of high-sensitivity cardiac troponin I (hs-cTnI), compared with conventional cardiac troponin T (cTnT) in the setting of non-ST elevation acute coronary syndromes. METHODS At hospital admission, a plasma sample was collected from 103 consecutive patients with unstable angina or non-ST elevation acute myocardial infarction. In this sample, troponin was measured both by hs-cTnI and cTnT methods. Their prognostic value was compared as to the occurrence of major cardiovascular events, defined as a combination of death, nonfatal acute myocardial infarction or refractory unstable angina during hospitalization. RESULTS During median hospitalization of 8 days (interquartile range = 5 - 11), the incidence of cardiovascular events was 10% (5 deaths, 3 non-fatal myocardial infarctions and 2 non-fatal refractory anginas). High-sensitivity troponin I significantly predicted cardiovascular events, with a C-statistics of 0.73 (95% CI = 0.59 - 0.87), similarly to cTnT (0.70; 95% CI = 0.55 - 0.84) - P = 0.75. The definition of positive cardiac marker that provided the best prognostic accuracy was hs-cTnI > 0.055 µg/L and cTnT > 0.010 µg/L, with equal sensitivity of 90% and specificity of 52% for both assays. Positive hs-cTnI was associated with 17% incidence of events, compared with 2% in patients with negative hs-cTnI (P = 0.02). CONCLUSION High-sensitivity troponin I predicts cardiovascular events similarly to conventional troponin T in the setting of non-ST-elevation ACS.

Does C-reactive Protein Add Prognostic Value to GRACE Score in Acute Coronary Syndromes?

Background The incremental prognostic value of plasma levels of C-reactive protein (CRP) in relation to GRACE score has not been established in patients with acute coronary syndrome (ACS) with non-ST segment elevation. Objective To test the hypothesis that CRP measurements at admission increases the prognostic value of GRACE score in patients with ACS. Methods A total of 290 subjects, consecutively admitted for ACS, with plasma material obtained upon admission CRP measurement using a high-sensitivity method (nephelometry) were studied. Cardiovascular outcomes during hospitalization were defined by the combination of death, nonfatal myocardial infarction or nonfatal refractory angina. Results The incidence of cardiovascular events during hospitalization was 15% (18 deaths, 11 myocardial infarctions, 13 angina episodes) with CRP showing C-statistics of 0.60 (95% CI = 0.51-0.70, p = 0.034) in predicting these outcomes. After adjustment for the GRACE score, elevated CRP (defined as the best cutoff point) tended to be associated with hospital events (OR = 1.89, 95% CI = 0.92 to 3.88, p = 0.08). However, the addition of the variable elevated CRP in the GRACE model did not result in significant increase in C-statistics, which ranged from 0.705 to 0.718 (p = 0.46). Similarly, there was no significant reclassification of risk with the addition of CRP in the predictor model (net reclassification = 5.7 %, p = 0.15). Conclusion Although CRP is associated with hospital outcomes, this inflammatory marker does not increase the prognostic value of the GRACE score.

Análise de Causalidade da Relação entre Sangramento e Letalidade de Síndromes Coronarianas Agudas Causality Analysis of the Relationship Between Bleeding and Lethality in Acute Coronary Syndromes

Background: Hemorrhagic events in Acute Coronary Syndromes (ACS) have been independently associated with death in international multicenter registries. However, that association has not been tested in Brazil and the true causal relationship between bleeding and death has not been completely shown.

Inconsistency prevents the valuable synergism of explanatory and pragmatic trails

To assess review articles on pragmatic trials in order to describe how authors define the aim of this type of study, how comprehensive methodological topics are covered, and which topics are most valued by authors.

A Multivariate Model for Prediction of Obstructive Coronary Disease in Patients with Acute Chest Pain: Development and Validation

Background Currently, there is no validated multivariate model to predict probability of obstructive coronary disease in patients with acute chest pain. Objective To develop and validate a multivariate model to predict coronary artery disease (CAD) based on variables assessed at admission to the coronary care unit (CCU) due to acute chest pain. Methods A total of 470 patients were studied, 370 utilized as the derivation sample and the subsequent 100 patients as the validation sample. As the reference standard, angiography was required to rule in CAD (stenosis ≥ 70%), while either angiography or a negative noninvasive test could be used to rule it out. As predictors, 13 baseline variables related to medical history, 14 characteristics of chest discomfort, and eight variables from physical examination or laboratory tests were tested. Results The prevalence of CAD was 48%. By logistic regression, six variables remained independent predictors of CAD: age, male gender, relief with nitrate, signs of heart failure, positive electrocardiogram, and troponin. The area under the curve (AUC) of this final model was 0.80 (95% confidence interval [95%CI] = 0.75 - 0.84) in the derivation sample and 0.86 (95%CI = 0.79 - 0.93) in the validation sample. Hosmer-Lemeshows test indicated good calibration in both samples (p = 0.98 and p = 0.23, respectively). Compared with a basic model containing electrocardiogram and troponin, the full model provided an AUC increment of 0.07 in both derivation (p = 0.0002) and validation (p = 0.039) samples. Integrated discrimination improvement was 0.09 in both derivation (p < 0.001) and validation (p < 0.0015) samples. Conclusion A multivariate model was derived and validated as an accurate tool for estimating the pretest probability of CAD in patients with acute chest pain.

DETERMINANTS AND APPROPRIATENESS OF DECISION FOR INVASIVE STRATEGY IN NON-ST-SEGMENT ELEVATION ACUTE CORONARY SYNDROMES

Risk stratification properly based on prognostic models should guide decision for invasive or selective strategy in non-ST-elevation acute coronary syndromes (NST-ACS). We aimed to (1) identify clinical determinants of invasive strategy in an environment that medical staff regularly uses the GRACE