RESUMO
BACKGROUND: Experimental studies have demonstrated that intravenous beta-blocker administration before coronary artery occlusion significantly reduces myocardial injury. Clinical studies have shown that intracoronary (IC) propranolol administration before percutaneous coronary intervention (PCI) delays myocardial ischemia. The present study tested the hypothesis that IC propranolol treatment protects ischemic myocardium from myocardial damage and reduces the incidence of myocardial infarction (MI) and short-term adverse outcomes after PCI. METHODS AND RESULTS: Patients undergoing PCI (n=150) were randomly assigned in a double-blind fashion to receive IC propranolol (n=75) or placebo (n=75). Study drug was delivered before first balloon inflation via an intracoronary catheter with the tip distal to the coronary lesion. Biochemical markers were evaluated through the first 24 hours and clinical outcomes to 30 days. Evidence of MI with creatine kinase-MB elevation after PCI was seen in 36% of placebo and 17% of propranolol patients (P=0.01). Troponin T elevation was seen in 33% of placebo and 13% of propranolol patients (P=0.005). At 30 days, the composite end point of death, postprocedural MI, non-Q-wave MI after PCI hospitalization, or urgent target-lesion revascularization occurred in 40% of placebo versus 18% of propranolol patients (hazard ratio 2.14, 95% CI 1.24 to 3.71, P=0.004). CONCLUSIONS: IC administration of propranolol protects the myocardium during PCI, significantly reducing the incidence of MI and improving short-term clinical outcomes.
Assuntos
Antagonistas Adrenérgicos beta/administração & dosagem , Angioplastia Coronária com Balão , Doença da Artéria Coronariana/terapia , Infarto do Miocárdio/prevenção & controle , Propranolol/administração & dosagem , Angioplastia Coronária com Balão/efeitos adversos , Aspirina/administração & dosagem , Biomarcadores/análise , Creatina Quinase/análise , Creatina Quinase Forma MB , Método Duplo-Cego , Feminino , Coração/efeitos dos fármacos , Humanos , Injeções Intra-Arteriais , Isoenzimas/análise , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Infarto do Miocárdio/etiologia , Inibidores da Agregação Plaquetária/administração & dosagem , Risco , Tamanho da Amostra , Análise de Sobrevida , Resultado do TratamentoRESUMO
BACKGROUND: Congestive heart failure is the leading cause of hospital admissions for adults in the United States. To our knowledge, there are limited data comparing the clinical presentation, hospital length of stay, and readmission in patients with preserved and decreased left ventricular (LV) systolic function. HYPOTHESIS: The goal of the study was to determine whether there are differences in clinical presentation, hospital length of stay, and readmission in patients with preserved (> or = 50%) and reduced (< 50%) systolic function. METHODS: We prospectively evaluated 187 patients admitted with congestive heart failure confirmed by the presence of pulmonary vascular congestion on chest x-ray, and with recent (< 6 months) documentation of LV systolic function by two-dimensional echocardiography. History and physical examination findings, patient demographics, comorbidities, discharge medications, and length of hospital stay data were documented. Readmission rate over a 6-month follow-up period was also documented. RESULTS: Of the 187 patients, 130 (70%) patients had an ejection fraction (EF) <50%, and 57 (30%) patients had an EF > or = 50%. Patients with EF < 50% were more likely to be men (54 vs. 37%, p = 0.03). African Americans (79 vs. 60%, p = 0.007), had a higher prevalence of previous stroke (17 vs. 5%, p = 0.03), and were more likely to carry no medical insurance at the time of admission (14 vs. 2%, p = 0.01) and to be discharged on digoxin (60 vs.30%, p<0.001). There were no significant differences in symptoms (exertional dyspnea, rest dyspnea, orthopnea, or paroxysmal nocturnal dyspnea), or in physical examination findings (S3, S4, elevated jugular venous pressure, rales, or peripheral edema). According to chest x-ray, patients with EF <50% had more frequent cardiomegaly (88 vs. 72% p = 0.008), but there were no differences in the presence of pleural effusion or pulmonary vascular congestion (p = NS). The mean length of stay was 5.9 and 5.2 days, respectively (p = 0.34). During the 6-month follow-up period, the readmission rates were 33% (43 patients) and 26% (15 patients), respectively (p = 0.36). CONCLUSION: The clinical presentation, hospital length of stay, and readmission rate for congestive heart failure are similar in patients with preserved and decreased LV systolic function.