Abstract 5212: Resolution of Pathological Q-waves is Associated With Improved Outcomes After Primary PCI for Acute Myocardial Infarction
Background: The presence of pathological Q-waves in patients presenting with ST-elevation myocardial infarction (STEMI) independently predicts 30-day mortality. A question that remains is whether new Q-waves which resolve within 30 days are predictive of an improved prognosis.
Methods: 3,189 patients with STEMI enrolled in the prospective, randomized Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction (HORIZONS-AMI) trial were evaluated for the presence of new and persistent Q-waves by serial electrocardiography. ECGs were performed at baseline, 60 minutes post PCI, at hospital discharge and at 30 days, and were interpreted by independent cardiologists at an academic ECG core laboratory. Net Adverse Clinical Events (NACE) was defined as Major Adverse Cardiovascular Events (MACE (death, reinfarction, stroke or repeat revascularization) or major bleeding unrelated to CABG.
Results: There were 2358 patients with new Q-waves either at baseline or which developed during hospitalization. Patients were classified for the presence of Q-wave resolution within 30 days (n=225) (Group A) or presence of persistent Q-waves (n=2133) (Group B). Group B patients were more likely to have a lower baseline left ventricular ejection fraction and a longer duration of symptom to balloon inflation time, and were less likely to have successful reperfusion as measured by post PCI infarct artery epicardial TIMI flow. Group B also had a significantly higher rate of NACE at 30-days (Table⇓).
Conclusions: In patients with STEMI undergoing primary PCI, resolution of new Q-waves present during hospitalization is associated with a higher baseline left ventricular ejection fraction, faster and more effective reperfusion, and an improved short-term prognosis.