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Prognostic importance of new small Q waves following non-ST-elevation acute coronary syndromes AMERICAN JOURNAL OF MEDICINE Alexander, J. H., Harrington, R. A., Bhapkar, M., Mahaffey, K. W., Lincoff, A. M., Ohman, E. M., Klootwijk, P., Pahlm, O., Henden, B., Deckers, J. W., Simoons, M. L., Califf, R. M., Wagner, G. S. 2003; 115 (8): 613-619

Abstract

To investigate the prognostic importance of new small Q waves following an acute coronary syndrome.We assessed 6-month mortality in 10501 patients with non-ST-elevation acute coronary syndromes who had survived 30 days and had both admission and 30-day electrocardiograms. Patients were stratified by whether they had no new Q waves (n = 9447), new 30- to 40-ms Q waves (n = 733), or new > or =40-ms Q waves (n = 321).Mortality was higher in patients with 30- to 40-ms Q waves than in those with no new Q waves (3.4% [25/733] vs. 2.4% [227/9447], P = 0.005), and even higher in those with > or =40-ms Q waves (5.3% [17/321], P = 0.002). After adjustment for baseline risk predictors, mortality remained higher in patients with new 30- to 40-ms Q waves (odds ratio [OR] = 1.30; 95% confidence interval [CI]: 0.85 to 1.98; P = 0.23) and those with new > or =40-ms Q waves (OR = 1.87; 95% CI: 1.13 to 3.09; P = 0.01).Patients with new small Q waves following a non-ST-elevation acute coronary syndrome are at increased risk of adverse outcomes. These small Q waves should be considered diagnostic of myocardial infarction. Further research should investigate whether even smaller QRS changes are prognostically important.

View details for DOI 10.1016/j.amjmed.2003.08.007

View details for Web of Science ID 000186883800003

View details for PubMedID 14656613