Relation between infarct artery patency at late angiography after acute myocardial infarction and signal-averaged electrocardiography

Patency of the infarct-related artery (IRA) after acute myocardial infarcti on has a strong, independent association with a lower mortality rate at 1 y ear.(1-3) A patent IRA is associated with improved left ventricular remodel ing(4) and reduced rates of sudden cardiac death.(1) The signal-averaged el ectrocardiogram (SAECG) is a noninvasive, computerized surface electrocardi ographic recording that can detect delayed low amplitude cardiac signals (" late potentials") in the terminal portion of the QRS complex or within the ST segment.(5) The presence of late potentials after myocardial infarction is a sensitive and powerful variable that is predictive of sustained ventri cular tachyarrhythmias.(6,7)