Abstract 2404: ECG Estimate Of Ischemic Acuteness and Time from Pain Onset for Predicting Myocardial Salvage in Patients Undergoing Primary Percutaneous Coronary Intervention
Background: The potential for salvage of jeopardized myocardium during coronary occlusion decreases as the duration of persistent ischemia is prolonged. Thus, it is important to be able to assess the acuteness of ischemia as a patient presents with signs of acute coronary syndrome. The aim of this study was to compare ECG estimate of ischemic acuteness and time from pain onset for predicting myocardial salvage in patients with first-time myocardial infarction (MI).
Methods: Thirteen patients with acutely revascularized first-time MI were studied. All patients had 99mTc tetrofosmin injected and an ECG recorded prior to the PCI. TIMI III flow was obtained in all patients. Single photon emission computed tomography (SPECT) was undertaken within 3 hours of the PCI to assess the myocardium at risk (MaR). Delayed contrast-enhanced magnetic resonance imaging (DE-MRI) was performed 1 week after admission for assessment of infarct size (IS) and infarct transmurality (IT). A salvage index was calculated as (MaR-IS)/MaR. The acuteness of ischemia was estimated both from patient history and from the Anderson-Wilkins (AW) acuteness score of the pre-PCI ECG.
Results: The figure⇓ shows the relationship between time of symptom onset and salvage index (A) and IT (C) as well as the relationship between AW acuteness score and salvage index (B) and IT (D). The time of symptom onset did not correlate with salvage index or IT. The AW acuteness score, however, showed a significant relationship with both salvage index and IT.
Conclusions: The initial ECG changes are superior to time from symptom onset to PCI for predicting myocardial salvage and IT in patients undergoing PCI of first-time MI.