Influencia del antecedente de intervención coronaria percutánea sobre los desenlaces angiográficos y clínicos en pacientes con infarto agudo de miocardio con elevación del segmento ST / Impact of previous percutaneous coronary intervention on angiographic and clinical outcomes in patients with ST-segment elevation myocardial infarction

Resumen Antecedentes: El pronóstico de los pacientes con infarto agudo de miocardio con elevación del segmento ST (IAMCEST) y antecedente de intervención coronaria percutánea (ICP) es incierto. Objetivos: Evaluar si la ICP previa en pacientes con IAMCEST incrementa el riesgo de eventos cardiovasculares mayores y si el flujo final epicárdico varía según la estrategia de reperfusión. Material y métodos: Subestudio de PHASE-MX, observacional, longitudinal y comparativo, de pacientes con IAMCEST reperfundidos en menos de 12 horas de iniciados los síntomas, divididos conforme el antecedente de ICP. El acaecimiento del criterio de valoración principal (muerte cardiovascular, reinfarto, insuficiencia cardíaca y choque cardiogénico) dentro de los 30 días se comparó con estimaciones de Kaplan-Meier, prueba de rangos logarítmicos y modelo de riesgos proporcionales de Cox. El flujo epicárdico final se evaluó con el sistema de clasificación del flujo TIMI después de la reperfusión. Resultados: Se incluyeron 935 pacientes, 85.6 % del sexo masculino, 6.9 % de los cuales tenía antecedente de ICP; 53 % recibió terapia farmacoinvasiva y 47 %, ICP primaria. La incidencia del criterio de valoración principal en pacientes con ICP previa fue de 9.8 % versus 13.3 % en aquellos sin ese antecedente (p = 0.06); 87.1 % de los pacientes con ICP previa obtuvo flujo final de grado TIMI 3 versus 75 % del grupo con estrategia farmacoinvasiva (p = 0.235). Conclusiones: El antecedente de ICP no incrementa el riesgo de eventos cardiovasculares mayores a los 30 días en pacientes con IAMCEST; sin embargo, impacta negativamente en el flujo sanguíneo angiográfico final de los pacientes que recibieron terapia farmacoinvasiva (en comparación con ICP primaria).

Abstract Background: The prognosis of patients with ST-segment elevation myocardial infarction (STEMI) and previous percutaneous coronary intervention (PCI) is uncertain. Objectives: To evaluate if previous PCI in patients with STEMI increases the risk of major cardiovascular events, and if final epicardial blood flow differs according to the reperfusion strategy. Material and methods: Observational, longitudinal, comparative sub-study of the PHASE-MX trial that included patients with STEMI and reperfusion within 12 hours of symptom onset, who were divided according to their history of PCI. The occurrence of the composite primary endpoint (cardiovascular death, re-infarction, congestive heart failure and cardiogenic shock) within 30 days was evaluated using Kaplan-Meier estimates, log-rank test and Cox proportional hazards model. Final epicardial blood flow was assessed using the TIMI grading system after reperfusion. Results: A total of 935 patients were included; 85.6% were males, and 6.9% had a history of PCI; 53% underwent pharmacoinvasive therapy, and 47%, primary PCI. The incidence of the composite primary endpoint at 30 days in patients with a history of PCI was 9.8% vs. 13.3% in those with no previous PCI (p = 0.06). Among the patients with previous PCI, 87.1% reached a final TIMI grade 3 flow after primary PCI vs. 75% in the group with pharmacoinvasive strategy (p = 0.235). Conclusions: A history of PCI does not increase the risk of major cardiovascular events at 30 days; however, it impacted negatively on the final angiographic blood flow of patients that received pharmacoinvasive therapy (compared to primary PCI).

Prediction of Salvaged Myocardium in Patients with Acute Myocardial Infarction after Primary Percutaneous Coronary Angioplasty using early Thallium-201 Redistribution Myocardial Perfusion Imaging / 대한핵의학회잡지

PURPOSE: The amount of salvaged myocardium is an important prognostic factor in patients with acute myocardial infarction (MI). We investigated if early Tl-201 SPECT imaging could be used to predict the salvaged myocardium and functional recovery in acute MI after primary PTCA. MATERIALS AND METHODS: In 36 patients with first acute MI treated with primary PTCA, serial echocardiography and Tl-201 SPECT imaging (5.8+/-2.1 days after PTCA) were performed. Regional wall motion and perfusion were quantified with on 16-segment myocardial model with 5-point and 4-point scaling system, respectively. RESULTS: Wall motion was improved in 78 of the 212 dyssynergic segments on 1 month follow-up echocardiography and 97 on 7 months follow-up echocardiography, which were proved to be salvaged myocardium. The areas under receiver operating characteristic curves of Tl-201 perfusion score for detecting salvaged myocardial segments were 0.79 for 1 month follow-up and 0.83 for 7 months follow-up. The sensitivity and specificity of Tl-201 redistribution images with optimum cutoff of 40% of peak thallium activity for detecting salvaged myocardium were 84.6% and 55.2% for 1 month follow-up, and 87.6% and 64.3% for 7 months follow-up, respectively. There was a linear relationship between the percentage of peak thallium activity on early redistribution imaging and the likelihood of segmental functional improvement 7 months after reperfusion. CONCLUSION: Tl-201 myocardial perfusion SPECT imaging performed early within 10 days after reperfusion can be used to predict the salvaged myocardium and functional recovery with high sensitivity during the 7 months following primary PTCA in patients with acute MI.

Estratégias de reperfusão precoce no infarto agudo do miocárdio / Early reperfusion strategies in acute myocardial infarction

PURPOSE: To describe the use of myocardial reperfusion strategies (percutaneous transluminal coronary angioplasty-PTCA and intravenous trombolysis) whenever it is possible to use emergency cinecoronariography in acute myocardial infarction (AMI). METHODS: The records of patients admitted with initial diagnosis of AMI, until six hours after the beginning of symptoms, were reviewed retrospectively, between March/92 and December/93. RESULTS: One hundred forty-three patients were admitted with suspected AMI. Eighty-one (57) presented definitive criteria for this diagnosis. Fifty-two patients (64) were admitted in the first six hours from the beginning of symptoms. Thirty-eight (73) were male and the mean age was 59 +/- 12 years. Cinecoronariography was indicated immediately in 36 of 52 (69) patients, with purpose to use PTCA. That was done in 30 (58). Two (4) patients were submitted to emergency surgical myocardial revascularization. Intravenous thrombolysis was used in 11 (21) patients. At admission, the conservative treatment was chosen for five out of nine left patients, based on clinical grounds. CONCLUSION: The availability of emergency cinecoronariography made an early reperfusion strategy possible in 83 of patients admitted with AMI in the first six hours after the beginning of symptoms

Objetivo - Descrever a utilização de estratégias de reperfusão miocárdica (angioplastia transluminal coronária primária - ATCP e a trombólise intravenosa) e o emprego da cinecoronariografia de emergência no infarto agudo do miocárdio (IAM). Métodos - Foram revistos, retrospectivamente, entre março/92 e dezembro/93, os prontuários dos pacientes admitidos com diagnóstico de IAM, com até 6h após o início dos sintomas. Resultados - Foram admitidos com suspeita de IAM, 143 pacientes dos quais 81 (57%) com critérios definitivos para este diagnóstico, sendo que 52 (64%) admitidos durante as 6 primeiras horas dos sintomas. Eram do sexo masculino 38 (73%), com média de idade de 59±12 anos. A cinecoronariografia foi indicada de forma imediata em 36 (69%) dos 52 pacientes, visando ATCP que foi realizada em 30 (58%). Dois (4%) pacientes foram encaminhados para cirurgia de revascularização miocárdica de emergência. A trombólise intravenosa foi utilizada em 11 (21%) pacientes. Na admissão optou-se pelo tratamento conservador em 5 dos 9 pacientes restantes, baseado no julgumento clínico. Conclusão - A disponibilidade da cinecoronariografia de emergência possibilitou a utilização de estratégias de reperfusão precoce em 83% dos pacientes admitidos com IAM durante as primeiras 6h