Predicting Outcome After Thrombolysis in Acute Myocardial Infarc
Background: Resolution of ST-segment elevation after thrombolysis for acute myocardial infarction has been shown to have prognostic significance 3 hours (180 minutes) after the initiation of therapy. Whether prognostically useful information can be achieved as early as 90 minutes after thrombolysis is unknown.
Methods: An electrocardiographic substudy of 2352 patients from the Global Use of Strategies To Open occluded coronary arteries (GUSTO-III) trial was undertaken to compare outcomes according to ST-segment resolution at 90 minutes versus 180 minutes after administration of thrombolytic therapy.
Results: Of 2352 patients in the substudy, 2241 had a baseline and 90-minute electrocardiogram, and 2218 had a baseline and 180-minute ECG. Complete ST-segment resolution occurred in 44.2% of patients at 90 minutes and 56.5% of patients at 180 minutes. ST-segment resolution at both 90 and 180 minutes was associated with lower 30-day and 1-year mortality. Multivariate analysis revealed ST-segment resolution at 90 minutes to be an equally strong predictor of 30-day mortality as resolution at 180 minutes. Patients who were at particularly high risk for mortality were those aged >70 years, those who presented with Killip class >1, and those with anterior infarctions.
Conclusions: The presence of ST-segment resolution on standard 12-lead electrocardiographic monitoring 90 minutes after thrombolysis is a useful independent predictor of mortality at 30 days and 1 year. The potential for obtaining prognostic results as early as 90 minutes after thrombolysis sets a new precedent for optimum electrocardiographic monitoring times in these patients.
The importance of early reperfusion after acute myocardial infarction (MI) has been clearly demonstrated. The physician's ability to predict patency of the infarct-related artery from clinical variables, however, is disappointing. Additionally, the relationship between patency, morbidity, and mortality is not completely understood. The generally low incidence of morbidity and mortality in clinical trials of acute MI makes it difficult to pinpoint specific prognostic indicators; thus, interest in biomarkers that are associated with differences in outcome has grown in recent years. This has led to a search for bedside clinical and electrocardiographic characteristics that may allow physicians to stratify patients undergoing thrombolysis into high- and low-risk groups. Such biomarkers would be particularly useful if they could be linked to a pathophysiologic result that could be altered for potential improvement in the prognosis.
The purpose of the Global Use of Strategies To Open occluded coronary arteries (GUSTO-III) electrocardiographic substudy was to determine prospectively whether these categories of ST-segment resolution would be applicable as early as 90 minutes after the initiation of thrombolytic therapy. Additionally, we sought to identify subgroups within the 3 strata that might be at particularly high risk. This triage of patients at 90 minutes after thrombolysis, if possible, could allow for earlier identification of, and more aggressive intervention in, high-risk patients.
Background: Resolution of ST-segment elevation after thrombolysis for acute myocardial infarction has been shown to have prognostic significance 3 hours (180 minutes) after the initiation of therapy. Whether prognostically useful information can be achieved as early as 90 minutes after thrombolysis is unknown.
Methods: An electrocardiographic substudy of 2352 patients from the Global Use of Strategies To Open occluded coronary arteries (GUSTO-III) trial was undertaken to compare outcomes according to ST-segment resolution at 90 minutes versus 180 minutes after administration of thrombolytic therapy.
Results: Of 2352 patients in the substudy, 2241 had a baseline and 90-minute electrocardiogram, and 2218 had a baseline and 180-minute ECG. Complete ST-segment resolution occurred in 44.2% of patients at 90 minutes and 56.5% of patients at 180 minutes. ST-segment resolution at both 90 and 180 minutes was associated with lower 30-day and 1-year mortality. Multivariate analysis revealed ST-segment resolution at 90 minutes to be an equally strong predictor of 30-day mortality as resolution at 180 minutes. Patients who were at particularly high risk for mortality were those aged >70 years, those who presented with Killip class >1, and those with anterior infarctions.
Conclusions: The presence of ST-segment resolution on standard 12-lead electrocardiographic monitoring 90 minutes after thrombolysis is a useful independent predictor of mortality at 30 days and 1 year. The potential for obtaining prognostic results as early as 90 minutes after thrombolysis sets a new precedent for optimum electrocardiographic monitoring times in these patients.
The importance of early reperfusion after acute myocardial infarction (MI) has been clearly demonstrated. The physician's ability to predict patency of the infarct-related artery from clinical variables, however, is disappointing. Additionally, the relationship between patency, morbidity, and mortality is not completely understood. The generally low incidence of morbidity and mortality in clinical trials of acute MI makes it difficult to pinpoint specific prognostic indicators; thus, interest in biomarkers that are associated with differences in outcome has grown in recent years. This has led to a search for bedside clinical and electrocardiographic characteristics that may allow physicians to stratify patients undergoing thrombolysis into high- and low-risk groups. Such biomarkers would be particularly useful if they could be linked to a pathophysiologic result that could be altered for potential improvement in the prognosis.
The purpose of the Global Use of Strategies To Open occluded coronary arteries (GUSTO-III) electrocardiographic substudy was to determine prospectively whether these categories of ST-segment resolution would be applicable as early as 90 minutes after the initiation of thrombolytic therapy. Additionally, we sought to identify subgroups within the 3 strata that might be at particularly high risk. This triage of patients at 90 minutes after thrombolysis, if possible, could allow for earlier identification of, and more aggressive intervention in, high-risk patients.