Prevalence and prognostic significance of fragmented QRS complex in middle-aged subjects with and without clinical or electrocardiographic evidence of cardiac disease

Am J Cardiol. 2014 Jul 1;114(1):141-7. doi: 10.1016/j.amjcard.2014.03.066. Epub 2014 Apr 18.


We wanted to evaluate the prevalence and prognostic value of the fragmented QRS (fQRS) complex, defined as changes in QRS morphology with various RSR'-patterns in 12-lead electrocardiogram (ECG) in a middle-aged general population. We evaluated the 12-lead ECGs of 10,904 Finnish middle-aged subjects (52% men, mean age 44 ± 8.5 years) with (n = 2,543) and without (n = 8,361) an evidence of cardiac disease drawn from general population and followed them for 30 ± 11 years. Fragmentation of the QRS complex was defined as various RSR'-patterns in at least 2 consecutive leads within the same territory (inferior II, III, aVF; lateral I, aVL, V4 to V6; anterior V1 to V3). Primary end points were death from any cause, cardiac, and arrhythmic deaths. In the total population, fQRS was present in 19.7% (n = 2,147) of subjects, including 15.7% (n = 1714) in inferior leads, 0.8% (n = 84) in lateral leads, and 2.9% (n = 314) in anterior leads. Fragmentation was not associated with increased mortality in subjects without a known cardiac disease. However, fQRS observed in lateral leads in subjects with an evidence of cardiac disease was associated with an increased risk of all-cause (p = 0.001), cardiac (p = 0.001), and arrhythmic (p = 0.004) mortalities. In conclusion, fQRS reflecting minor intraventricular conduction defect is a common finding, especially in the inferior leads, but it is not a sign of increased risk of mortality in subjects without a known cardiac disease. Lateral fQRS, which is less commonly observed in the ECG, is associated with a worse outcome in patients with a known cardiac disease.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Electrocardiography
  • Female
  • Finland / epidemiology
  • Heart Conduction System / physiopathology*
  • Heart Diseases / diagnosis*
  • Heart Diseases / epidemiology
  • Heart Diseases / physiopathology*
  • Humans
  • Male
  • Middle Aged
  • Prevalence
  • Prognosis