Blog
About

  • Record: found
  • Abstract: found
  • Article: not found

Significance of a fragmented QRS complex versus a Q wave in patients with coronary artery disease.

Circulation

Sensitivity and Specificity, Tomography, Emission-Computed, Single-Photon, diagnosis, Electrocardiography, Coronary Artery Disease, methods, standards, Exercise Test, Humans, Male, Middle Aged, Myocardial Infarction, Predictive Value of Tests, Aged, Cohort Studies

Read this article at

ScienceOpenPublisherPubMed
Bookmark
      There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

      Abstract

      Q waves on a 12-lead ECG are markers of a prior myocardial infarction (MI). However, they may regress or even disappear over time, and there is no specific ECG sign of a non-Q-wave MI. Fragmented QRS complexes (fQRSs), which include various RSR' patterns, without a typical bundle-branch block are markers of altered ventricular depolarization owing to a prior myocardial scar. We postulated that the presence of an fQRS might improve the ability to detect a prior MI compared with Q waves alone by ECG. A cohort of 479 consecutive patients (mean+/-SD age, 58.2+/-13.2 years; 283 males) who were referred for nuclear stress tests was studied. The fQRS included various morphologies of the QRS (<120 ms), which included an additional R wave (R') or notching in the nadir of the S wave, or >1 R' (fragmentation) in 2 contiguous leads, corresponding to a major coronary artery territory. The Q wave was present in 71 (14.8%) patients, an fQRS was present in 191 (34.9%) patients, and an fQRS and/or a Q wave was present in 203 (42.3%) patients. Sensitivity, specificity, and the negative predictive value for myocardial scar as detected by single photon emission computed tomography analysis were 36.3%, 99.2%, and 70.8%, respectively, for the Q wave alone; 85.6%, 89%, and 92.7%, respectively, for the fQRS; and 91.4%, 89%, and 94.2%, respectively, for the Q wave and/or fQRS. The fQRS on a 12-lead ECG is a marker of a prior MI, defined by regional perfusion abnormalities, which has a substantially higher sensitivity and negative predictive value compared with the Q wave.

      Related collections

      Author and article information

      Journal
      10.1161/CIRCULATIONAHA.105.595892
      16717150

      Comments

      Comment on this article