Predictores clínicos de no-reflujo en la angioplastia coronaria por infarto agudo de miocardio;
Clinical Predictors of No-Reflow in Percutaneous Coronary Intervention for Acute Myocardial Infarction

El fenómeno de no-reflow en el contexto de la angioplastia por infarto agudo de miocardio (IAM) es un hecho relativamente frecuente y asociado con peor pronóstico. Con el objetivo de determinar predictores clínicos de no-reflow antes del inicio del procedimiento se analizaron 742 pacientes con IAM de <12hs de evolución tratados con angioplastia primaria. Se excluyeron los pacientes con flujo epicardico TIMI 0 posintervención y se consideró no-reflow a la presencia de flujo TIMI 1-2 pos-angioplastia inmediato en ausencia de lesión residual. Se analizaron variables demográficas, factores de riesgo coronario, antecedentes y demora al tratamiento. Se realizó un análisis multivariado por regresión logística múltiple para determinar el valor pronóstico independiente de las variables relacionadas al no-reflow. Resultados: Se incluyeron 675 pacientes. Presentaron fenómeno de no-reflow 119 pacientes (17,6%). Los pacientes con no-reflow presentaron mayor edad (60,8±12 vs 57,0±11; p=0,0001) y menor frecuencia de tabaquismo activo (58,8 vs 67,8%, p=0,03) y antecedentes familiares (22,7 vs 37,8%, p=0,0007), sin diferencias significativas en el resto de los factores de riesgo coronario y antecedentes cardiovasculares. Presentaron también con mayor frecuencia signos clínicos de insuficiencia cardíaca al ingreso (17,6 vs 10,1%, p=0,01) así como mayor demora al tratamiento (240 [151-360] vs 195 [120-302] minutos, p=0,02). El análisis multivariado determinó que los predictores independientes de no-reflow fueron: edad >60 años y demora al tratamiento >3 horas. Conclusión: La edad avanzada y la demora al tratamiento resultaron predictores clínicos independientes de no-reflow. La confirmación de estos hallazgos en estudios prospectivos permitiría implementar estrategias para prevenir su aparición y, eventualmente, mejorar los resultados clínicos a largo plazo.

BackgroundThe no-reflow phenomenon in the setting of primary coronary intervention for acutemyocardial infarction (AMI) is relatively common and is associated with adverse outcomes.The detection of clinical variables associated with this phenomenon beforethe procedure might help to adopt preventive measures and thus improve the results.ObjectiveThe aim of this study was to identify clinical predictors of the no-reflow phenomenonin the setting of percutaneous coronary intervention for ST-segment elevation acutemyocardial infarction, prior to the procedure.MethodsA total of 742 patients with AMI < 12 hours since onset of symptoms treated withprimary percutaneous coronary intervention were analyzed. Patients with epicardialTIMI grade 0 flow after the procedure were excluded. No-reflow was considered asthe presence of TIMI grade 1-2 flow immediately after the procedure in the absenceof residual stenosis. Demographic variables, coronary risk factors, family history anddelay to reperfusion were analyzed. Multivariate logistic regression was used to determinethe independent prognostic value of the variables associated with no-reflow.ResultsA total of 675 patients were included. The no-reflow phenomenon was present in 119patients (17.6%). Patients with no-reflow were older (60.8 ± 12 vs. 57.0 ± 11 years;p = 0.0001) and had less prevalence of current smoking (58.8% vs. 67.8%, p = 0.03)and of previous history (22.7% vs. 37.8%, p = 0.0007), with no significant differencesin the rest of coronary risk factors and history of cardiovascular disease. AnteriorAMI (58.8% vs. 43.7%, p = 0.002), heart failure at admission (17.6% vs.10.1%, p= 0.01) and delay to reperfusion (240 [151-360] vs.195 [120-302] minutes, p=0.02)were more frequent in the no-reflow group. Multivariate analysis identified age > 60years, anterior infarction and delay to reperfusion > 3 hours as independent predictorsof no-reflow.ConclusionAdvanced age, anterior infarction and delay to reperfusion were independent clinicalpredictors of no-reflow. The confirmation of these findings in prospective studiesmight allow the implementation of strategies to prevent this phenomenon and eventuallyimprove the long-term clinical outcomes.