118 ECGS Pre and Early Post Primary PCI : Important Predictor of In-Hospital Adverse Outcomes in STEMI Population

Abstract

BackgroundPrognostic indicators have been available for patients with acute myocardial infarction (MI). These prognostic variables can be categorised into: clinical, physical findings, ECG variables, biomarkers and angiographic variables. However, many of these are complex, not readily available at the bedside or lack the necessary predictive accuracy. Therefore, aimed to assess the association of ST segment recovery post PCI, assessed using 4 methods, with important clinical events in a ST elevation MI (STEMI) population managed with primary percutaneous coronary intervention (PCI) and contemporary pharmacotherapy.MethodsThis retrospective study included all consecutive STEMI patients undergoing primary PCI in metropolitan Vancouver between May 2007 and September 2010 and had evaluable ECGs pre and post primary PCI. Patients with bundle branch block were excluded. Electronic calipers were used to quantify the degree of ST-segment shift (elevation/ depression) in each lead averaged over 3 beats on an ECG performed before and within 90-mins post primary PCI. ECG analysis was carried out blinded to the clinical outcomes. The primary analysis was performed using logistic regression model for the associations between ST-segment recovery and the composite of in-hospital mortality, congestive heart failure, cardiogenic shock, and recurrent myocardial infarction after the post-PCI ECG adjusting for major confounding variables.ResultsOur cohort consisted of 419 patients, with 75% males. In 55% of the cases the location of the STEMI was non-anterior and 91% of the cohort had both ST elevation and depression on the diagnostic ECG. The median time for post-PCI ECG was 87 mins. The composite endpoint occurred in 21% of patients. On univariate analysis: 1) Worst single lead ST elevation recovery ≥50% vs. <50% (p=0.05), 2) Summed ST (ΣST) elevation recovery μ50% vs. <50% (p=0.001), 3) ST elevation and depression vs. ST elevation on initial ECG (p=0.004) and 4) ΣST deviation (elevation and depression) percent recovery (p<0.001) correlated with the primary outcome. In the multiple regression analysis, the model including the initial ECG deviation and ΣST deviation recovery percent showed the best fit to the data, where every 10 units increase in recovery is associated with 16% reduction in risk for composite event (Odds Ratio=0.84 (95% CI, 0.77, 0.92)).ConclusionSummed ST segment recovery on a post primary PCI ECG provides important prognostic information in STEMI patients. Furthermore, the pre and post Primary PCI ECGs help identify those at continuing risk for morbid and mortal events: thus assisting clinicians in planning further diagnostics and therapy. BackgroundPrognostic indicators have been available for patients with acute myocardial infarction (MI). These prognostic variables can be categorised into: clinical, physical findings, ECG variables, biomarkers and angiographic variables. However, many of these are complex, not readily available at the bedside or lack the necessary predictive accuracy. Therefore, aimed to assess the association of ST segment recovery post PCI, assessed using 4 methods, with important clinical events in a ST elevation MI (STEMI) population managed with primary percutaneous coronary intervention (PCI) and contemporary pharmacotherapy. Prognostic indicators have been available for patients with acute myocardial infarction (MI). These prognostic variables can be categorised into: clinical, physical findings, ECG variables, biomarkers and angiographic variables. However, many of these are complex, not readily available at the bedside or lack the necessary predictive accuracy. Therefore, aimed to assess the association of ST segment recovery post PCI, assessed using 4 methods, with important clinical events in a ST elevation MI (STEMI) population managed with primary percutaneous coronary intervention (PCI) and contemporary pharmacotherapy. MethodsThis retrospective study included all consecutive STEMI patients undergoing primary PCI in metropolitan Vancouver between May 2007 and September 2010 and had evaluable ECGs pre and post primary PCI. Patients with bundle branch block were excluded. Electronic calipers were used to quantify the degree of ST-segment shift (elevation/ depression) in each lead averaged over 3 beats on an ECG performed before and within 90-mins post primary PCI. ECG analysis was carried out blinded to the clinical outcomes. The primary analysis was performed using logistic regression model for the associations between ST-segment recovery and the composite of in-hospital mortality, congestive heart failure, cardiogenic shock, and recurrent myocardial infarction after the post-PCI ECG adjusting for major confounding variables. This retrospective study included all consecutive STEMI patients undergoing primary PCI in metropolitan Vancouver between May 2007 and September 2010 and had evaluable ECGs pre and post primary PCI. Patients with bundle branch block were excluded. Electronic calipers were used to quantify the degree of ST-segment shift (elevation/ depression) in each lead averaged over 3 beats on an ECG performed before and within 90-mins post primary PCI. ECG analysis was carried out blinded to the clinical outcomes. The primary analysis was performed using logistic regression model for the associations between ST-segment recovery and the composite of in-hospital mortality, congestive heart failure, cardiogenic shock, and recurrent myocardial infarction after the post-PCI ECG adjusting for major confounding variables. ResultsOur cohort consisted of 419 patients, with 75% males. In 55% of the cases the location of the STEMI was non-anterior and 91% of the cohort had both ST elevation and depression on the diagnostic ECG. The median time for post-PCI ECG was 87 mins. The composite endpoint occurred in 21% of patients. On univariate analysis: 1) Worst single lead ST elevation recovery ≥50% vs. <50% (p=0.05), 2) Summed ST (ΣST) elevation recovery μ50% vs. <50% (p=0.001), 3) ST elevation and depression vs. ST elevation on initial ECG (p=0.004) and 4) ΣST deviation (elevation and depression) percent recovery (p<0.001) correlated with the primary outcome. In the multiple regression analysis, the model including the initial ECG deviation and ΣST deviation recovery percent showed the best fit to the data, where every 10 units increase in recovery is associated with 16% reduction in risk for composite event (Odds Ratio=0.84 (95% CI, 0.77, 0.92)). Our cohort consisted of 419 patients, with 75% males. In 55% of the cases the location of the STEMI was non-anterior and 91% of the cohort had both ST elevation and depression on the diagnostic ECG. The median time for post-PCI ECG was 87 mins. The composite endpoint occurred in 21% of patients. On univariate analysis: 1) Worst single lead ST elevation recovery ≥50% vs. <50% (p=0.05), 2) Summed ST (ΣST) elevation recovery μ50% vs. <50% (p=0.001), 3) ST elevation and depression vs. ST elevation on initial ECG (p=0.004) and 4) ΣST deviation (elevation and depression) percent recovery (p<0.001) correlated with the primary outcome. In the multiple regression analysis, the model including the initial ECG deviation and ΣST deviation recovery percent showed the best fit to the data, where every 10 units increase in recovery is associated with 16% reduction in risk for composite event (Odds Ratio=0.84 (95% CI, 0.77, 0.92)). ConclusionSummed ST segment recovery on a post primary PCI ECG provides important prognostic information in STEMI patients. Furthermore, the pre and post Primary PCI ECGs help identify those at continuing risk for morbid and mortal events: thus assisting clinicians in planning further diagnostics and therapy. Summed ST segment recovery on a post primary PCI ECG provides important prognostic information in STEMI patients. Furthermore, the pre and post Primary PCI ECGs help identify those at continuing risk for morbid and mortal events: thus assisting clinicians in planning further diagnostics and therapy.