The American Journal of Medicine
Volume 122, Issue 2 , Pages 144-151, February 2009

Predictors and Implications of Q-Waves in ST-Elevation Acute Coronary Syndromes

  • Troy LaBounty, MD

      Affiliations

    • Weill Cornell Medical College, New York, NY
    • ,
  • Hitinder S. Gurm, MD

      Affiliations

    • University of Michigan, Ann Arbor, Mich
    • Ann Arbor Veterans Administration Hospital, Ann Arbor, Mich
    • ,
  • Shaun G. Goodman, MD

      Affiliations

    • Terrence Donnelly Heart Centre, Division of Cardiology, St. Michael's Hospital, University of Toronto, Ontario, Canada
    • Canadian Heart Research Centre, Toronto, Ontario, Canada
    • ,
  • Gilles Montalescot, MD, PhD

      Affiliations

    • Centre Hospitalier Universitaire Pitié-Salpêtrière, Paris, France
    • ,
  • Jose Lopez-Sendon, MD

      Affiliations

    • Hospital Universitario La Paz, Madrid, Spain
    • ,
  • Ann Quill, MA

      Affiliations

    • University of Massachusetts, Worcester
    • ,
  • Kim A. Eagle, MD

      Affiliations

    • University of Michigan, Ann Arbor, Mich
    • Corresponding Author InformationRequests for reprints should be addressed to Kim A Eagle, MD, Cardiovascular Center, University of Michigan, 1500 East Medical Center Drive, Room 2135-B, Ann Arbor, MI 48109-5852
    • ,
  • GRACE Investigators

Abstract 

Background

Q-waves in ST-elevation acute coronary syndromes carry adverse implications. We sought to determine the frequency, predictors, and implications of Q-waves in the current era that includes primary percutaneous coronary interventions.

Methods

There were 14,916 patients evaluated in a multicenter observational study. They presented with ST-elevation acute coronary syndromes between 1999 and 2006. Clinical variables were compared between patients with versus without presenting Q-waves, with an additional comparison in the latter group between those with versus without subsequent development of Q-waves.

Results

ST-elevation myocardial infarction occurred in 88.6% of patients. Q-waves were present on the initial electrocardiogram in 3929 patients and developed later in an additional 3085 patients. The incidence of Q-waves at presentation or during hospitalization decreased from 61% to 39% between 1999 and 2006 (linear trend P<.001). Both presenting and subsequent Q-waves were associated with greater likelihood of coronary occlusions and higher cardiac marker elevations (P <.001). Multivariate analysis showed that presenting Q-waves were associated with male sex (odds ratio [OR] 1.28), increased age (OR 1.06 per 5 years), diabetes (OR 1.26), smoking (OR 1.11), chronic aspirin (OR 0.79), acute aspirin (OR 0.87), other chronic cardiac medications (OR 0.80), prior heart failure (OR 0.67), and prior coronary artery disease (OR 0.61). Presenting Q-waves were independently associated with increased in-hospital mortality (OR 1.46), but Q-waves at presentation or during hospitalization did not impact 6-month mortality.

Conclusions

Q-waves in ST-elevation acute coronary syndromes are decreasing in incidence. Q-waves are a major determinant of in-hospital mortality, and targeted interventions should be directed to these high-risk patients.

Keywords: Acute coronary syndrome, Electrocardiography, Myocardial infarction, Myocardial ischemia

 

 Funding: This research was supported by an unrestricted grant from Sanofi-Aventis, Paris, France. The Global Registry of Acute Coronary Events is supported by an unrestricted educational grant from Sanofi-Aventis to the Center for Outcomes Research, University of Massachusetts Medical School. Sanofi-Aventis had no involvement in the collection, analysis, and interpretation of data; in the writing of the report; or in the decision to submit the paper for publication. The design, conduction, and interpretation were undertaken by an independent steering committee.

 Conflict of Interest: There are no other conflicts of interest for any of the authors.

 Authorship: All authors meet criteria for authorship including access to the data and all authors had a role in the writing of the manuscript.

PII: S0002-9343(08)00980-7

doi:10.1016/j.amjmed.2008.08.029

The American Journal of Medicine
Volume 122, Issue 2 , Pages 144-151, February 2009

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