ABSTRACT
Resumo Fundamento A insuficiência cardíaca com fração de ejeção reduzida (ICFEr) é uma doença de alta prevalência que requer hospitalizações repetidas e causa morbimortalidade significativa. Portanto, o reconhecimento precoce de preditores de resultados desfavoráveis é essencial para o manejo do paciente. Objetivo O objetivo do presente estudo é investigar a relação entre realce tardio pelo gadolínio (RTG) detectado por ressonância magnética cardíaca (RMC) e os parâmetros de repolarização, como o intervalo QT corrigido (QTc), intervalo Tp-e, ângulo QRS-T frontal detectado pelo eletrocardiograma (ECG) de 12 derivações na ICFEr. Método Neste estudo observacional, retrospectivo, de centro único, foram incluídos 97 pacientes consecutivos com ICFEr submetidos à RMC. A população do estudo foi dividida em dois grupos, de acordo com a presença de RTG. Foram registradas medidas ecocardiográficas e de RMC e características demográficas. Os intervalos QTc, intervalos Tp-e, e ângulos QRS-T frontais foram calculados a partir do ECG. Um valor de p <0,05 foi considerado estatisticamente significativo. Resultados O RTG foi detectado em 52 (53,6%) de 97 pacientes com ICFEr. Os intervalos QTc (p=0,001), intervalos Tp-e (p<0,001), e os ângulos QRS-T frontais (p<0,001) foram significativamente maiores no grupo RTG quando comparados ao grupo não-RTG. Na análise de regressão univariada realizada para investigar os preditores de RTG na ICFEr, todos os três parâmetros de repolarização alcançaram valores significativos, mas na análise multivariada o único parâmetro de repolarização que permaneceu significativo foi o intervalo Tp-e (OR = 1,085 IC 95% 1,032-1,140, p=0,001). Conclusão Com o prolongamento do intervalo Tp-e, pode-se prever a presença de fibrose miocárdica, a qual é um substrato arritmogênico, em pacientes com ICFEr.
Abstract Background Heart failure with reduced ejection fraction (HFrEF) is a highly prevalent disease that requires repeating hospitalizations, causes significant morbidity and mortality. Therefore, early recognition of poor outcome predictors is essential for patient management. Objective The aim of the present study is to investigate the relationship between late gadolinium enhancement (LGE) detected by cardiac magnetic resonance (CMR) and repolarization parameters such as corrected QT (QTc) interval, Tp-e interval, frontal QRS-T angle detected by 12 lead electrocardiograph (ECG) in HFrEF. Method In this single-center, retrospective observational study included 97 consecutive HFrEF patients who had CMR scan. Study population was divided into two groups according to the presence of LGE. Echocardiographic and CMR measurements and demographic features were recorded. QTc intervals, Tp-e intervals, frontal QRS-T angles were calculated from the ECG. A p-value less than 0.05 was considered statistically significant. Results LGE was detected in 52 (53.6%) out of 97 HFrEF patients. QTc intervals (p=0.001), Tp-e intervals (p<0.001), frontal QRS-T angles (p<0.001) were found to be significantly higher in LGE group when compared to non-LGE group. In univariate regression analysis which was performed to investigate the predictors of LGE in HFrEF, all three repolarization parameters were reached significant values but in multivariate analysis the only repolarization parameter remained significant was Tp-e interval (OR=1.085 95% CI 1.032-1.140, p=0.001). Conclusion With the prolongation of the Tp-e interval, the presence of myocardial fibrosis which is an arrhythmogenic substrate, can be predicted in patients with HFrEF.
Subject(s)
Humans , Gadolinium , Heart Failure/diagnostic imaging , Stroke Volume , Predictive Value of Tests , Contrast MediaABSTRACT
Abstract Background: A subset of patients who take antiplatelet therapy continues to have recurrent cardiovascular events which may be due to antiplatelet resistance. The effect of low response to aspirin or clopidogrel on prognosis was examined in different patient populations. Objective: We aimed to investigate the prevalence of poor response to dual antiplatelet therapy and its relationship with major adverse cardiovascular events (MACE) in young patients with ST-elevation myocardial infarction (STEMI). Methods: In our study, we included 123 patients under the age of 45 with STEMI who underwent primary percutaneous intervention. A screening procedure to determine both aspirin and clopidogrel responsiveness was performed on the fifth day of admission. We followed a 2x2 factorial design and patients were allocated to one of four groups, according to the presence of aspirin and/or clopidogrel resistance. Patients were followed for a three-year period. A p-value less than 0.05 was considered statistically significant. Results: We identified 48% of resistance against one or more antiplatelet in young patients with STEMI. More MACE was observed in patients with poor response to dual platelet therapy or to clopidogrel compared those with adequate response to the dual therapy (OR: 1.875, 1.144-3.073, p < 0.001; OR: 1.198, 0.957-1.499, p = 0.036, respectively). After adjustment for potential confounders, we found that poor responders to dual therapy had 3.3 times increased odds for three-year MACE than those with adequate response to the dual therapy. Conclusion: Attention should be paid to dual antiplatelet therapy in terms of increased risk for cardiovascular adverse events especially in young patients with STEMI.
Resumo Fundamento: Um subgrupo de pacientes que recebem terapia antiplaquetária continua a apresentar eventos cardiovasculares recorrentes, possivelmente por resistência aos medicamentos. O efeito da baixa resposta à aspirina ou ao clopidogrel sobre o prognóstico foi avaliado em diferentes populações. Objetivo: Investigar a prevalência de baixa resposta à terapia antiplaquetária e sua relação com eventos adversos cardiovasculares em pacientes jovens com infarto do miocárdio com supradesnivelamento do segmento ST (IAMCST). Métodos: Em nosso estudo, incluímos 123 pacientes com IAMCST e idade inferior a 45 anos, submetidos à intervenção percutânea primária. No quinto dia após admissão hospitalar, os pacientes foram rastreados quanto à capacidade de resposta à aspirina e ao clopidogrel. Seguimos um delineamento fatorial 2x2 e os pacientes foram alocados a um dos quatro grupos formados segundo presença de resistência à aspirina e/ou ao clopidogrel. Os pacientes foram acompanhados por um período de três anos. Um valor de P inferior a 0,05 foi considerado estatisticamente significativo. Resultados: Nós identificamos 48% de resistência a um ou mais agentes antiplaquetários em pacientes jovens com IAMCST. Houve maior ocorrência de MACE em pacientes com baixa resposta à terapia antiplaquetária dupla ou ao clopidogrel em comparação àqueles com resposta adequada à terapia dupla (OR: 1,875; 1,144-3,073; p < 0,001; OR: 1,198; 0,957-1,499; p = 0.036, respectivamente). Após ajuste quanto a possíveis fatores de confusão, pacientes com baixa resposta à terapia dupla apresentaram risco 3,3 vezes maior para MACE em três anos em comparação àqueles com resposta adequada a essa terapia. Conclusão: Atenção deve ser dada à resistência à terapia antiplaquetária dupla quanto ao risco aumentado de eventos adversos cardiovasculares, especialmente em pacientes jovens com IAMCST.
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Platelet Aggregation Inhibitors/therapeutic use , Aspirin/therapeutic use , ST Elevation Myocardial Infarction/drug therapy , Clopidogrel/therapeutic use , Time Factors , Drug Resistance , Cardiovascular Diseases/etiology , Logistic Models , Multivariate Analysis , Prospective Studies , Risk Factors , Follow-Up Studies , Treatment Outcome , Kaplan-Meier Estimate , ST Elevation Myocardial Infarction/complications , ST Elevation Myocardial Infarction/mortalityABSTRACT
The primary goal of coronary artery bypass grafting is to achieve complete revascularization with grafts that will remain patent throughout the patient's lifetime. This study investigated the association between bypass graft patency and comorbidity burden determined by Charlson comorbidity index (CCI) among patients with previous bypass operation who underwent a control angiography. One-hundred and two patients who had undergone CABG in the past were included to the study. Critical stenosis was defined as 50% or greater coronary luminal obstruction of any coronary vessel or its lateral branch. Patients were divided into 2 groups group 1; critical graft stenosis; (54 pts; 41M, mean age 66.5 ± 7.8 years), group 2; graft patent (48 pts; 31M, mean age; 65.9 ± 8.2 years). Charlson comorbidity index (CCI) and modified CCI scores were used for detecting comorbidities. The comparison of continuous variables between the control and critical CAD groups was performed by the independent sample test. A p value less than 0.05 was considered statistically significant. The two groups were statistically similar with respect to demographic properties, time since bypass operation, cardiovascular risk factors, systolic blood pressure, heart rate, medications used, complete blood counts parameters, and lipid profiles. CCI was significantly higher in Group 1 compared to Group 2 (7.14 ± 2.02 vs4.72 ± 1.58; p < 0.001). Modified CCI scores were also higher in Group 1 than in Group 2 (6.14 ± 2.02 vs 3.73 ± 1.60; p < 0.001). Graft occlusion was more common among patients with a high comorbidity burden. CCI scoring system may be helpful for determining patients at increased risk at both the preoperative and postoperative periods