Coronary artery disease
Prognostic Significance of Fragmented QRS Complex for Predicting the Risk of Recurrent Cardiac Events in Patients With Q-Wave Myocardial Infarction

https://doi.org/10.1016/j.amjcard.2007.03.063Get rights and content

There are limited data regarding the prognostic value of QRS complex fragmentation, defined as changes in QRS morphology (<120 ms) with different RSR′ patterns: additional R waves, notched S wave, or >1 R′ wave. The purpose of our analysis was to assess the prognostic value of presence of Q waves and QRS fragmentation for predicting recurrent cardiac events, defined as cardiac death, nonfatal myocardial infarction (MI), or unstable angina, whichever occurs first, in 350 patients with first Q-wave MI. In follow-up (2 months on average) electrocardiograms (ECGs), 277 patients (79%) had persistent Q waves and 73 (21%) had resolution of Q waves. Independently of Q waves, presence of QRS complex fragmentation was found in 187 patients (53%). Resolved Q waves on 2-month ECGs was associated with worsened prognosis (adjusted hazard ratio [HR] 2.33, p = 0.007), whereas presence of any fragmented QRS did not increase risk of recurrent cardiac events (adjusted HR 0.93, p = 0.79). Among patients for whom Q waves disappeared on 2-month ECGs, patients with QRS fragmentation (n = 37) had over twofold higher risk of recurrent events (adjusted HR 2.68, p = 0.004) compared with those without fragmented QRS and persistent Q waves. In conclusion, presence of fragmented QRS independently of Q waves was not associated with increased risk of recurrent events in the general population of patients after MI. However, among patients with resolved Q waves, fragmented QRS was associated with increased risk of cardiac events. Fragmented QRS complex should not be neglected in patients with transient Q waves after myocardial infarction.

Section snippets

Methods and Results

The Multicenter Study of Myocardial Ischemia (MSMI) study enrolled 936 patients from 12 centers in the United States, Canada, and Israel. Enrollment began on July 1, 1988 and ended on May 31, 1991 with follow-up through November 30, 1991. All patients admitted to the coronary care unit with documented MI or unstable angina were considered for enrollment. Full details and major results of this study have been previously published.7 Confirmation of enzyme level elevation was necessary for the

Discussion

Our analysis of patients with Q-wave MI showed that presence of persistent Q waves on the ECG in the stable postinfarction period (2 months after MI on average) is associated with a more favorable prognosis compared with patients with resolved Q waves. In patients with resolved Q waves, fragmentation of the QRS complex, identified independently of the presence of Q waves, was associated with increased risk of cardiac events. The risk of the patients who had resolved Q waves and did not have QRS

References (11)

There are more references available in the full text version of this article.

Cited by (115)

  • The relation between QRS complex fragmentation and segmental abnormalities of the myocardial contractility in patients with coronary artery disease

    2021, Indian Heart Journal
    Citation Excerpt :

    The fQRS, evaluated on the 12-lead electrocardiogram (ECG), represents a delay in ventricular conduction caused by the presence of a myocardial scar. Even without being specific to CAD, it was associated to an increased risk of mortality and arrhythmic events as an addition to the already known ejection fraction (EF), which proved to be a good prognostic marker.16–24 The fQRS was defined as a QRS complex with duration of less than 120 ms and at least one notch in the R or S wave in two or more leads belonging to the same coronary territory.21–26

  • The prognostic value of the combined use of QRS distortion and fragmented QRS in patients with acute STEMI undergoing primary percutaneous coronary intervention

    2018, Journal of Electrocardiology
    Citation Excerpt :

    Previous studies showed that QRS distortion was associated with more advanced stage of infarction, higher risk of re-infarction, increased in-hospital mortality rate, lower left ventricular functions, and poor prognosis in patients with acute STEMI undergoing pPCI [8]. Similarly, the associations of fQRS with increased in-hospital mortality, sudden cardiac death, cardiac arrhythmia, lower LVEF, and adverse outcomes have also been reported [10,17,19,20]. However, the prognostic value of the combined use of these two parameters in acute STEMI has not been investigated yet.

View all citing articles on Scopus
View full text