Subclinical left ventricular dysfunction revealed by circumferential 2D strain imaging in patients with coronary artery disease and fragmented QRS complex

Heart Rhythm. 2012 Jun;9(6):928-35. doi: 10.1016/j.hrthm.2012.01.007. Epub 2012 Jan 11.

Abstract

Background: Fragmented QRS (fQRS) complexes on a routine 12-lead electrocardiogram were associated with adverse cardiac events, including sudden death in patients with coronary artery disease (CAD).

Objective: To investigate the relationship between the fQRS complex and global and regional left ventricular (LV) functions in patients with CAD.

Methods: The study consisted of 176 patients (68 ± 9 years; 145 [82%] men) with CAD with narrow QRS duration and preserved LV ejection fraction (>45%). All patients underwent detailed 2-dimensional speckle-tracking echocardiography to determine global and segmental (basal, middle, and apical) LV strains and strain rates and were prospectively followed-up in the outpatient clinic.

Results: Fifty-five patients (31%) had fQRS complexes. Global, middle, and apical LV longitudinal, radial, and circumferential strains and strain rates were significantly lower in the fQRS group than in the non-fQRS group (all P <.05). Multivariate logistic regression analysis revealed that the fQRS complex was associated with decreased global circumferential strain (odds ratio 1.19; 95% confidence interval 1.06-1.33; P = .003) and multivessel disease (odds ratio 3.69; 95% confidence interval 1.35-10.08; P = .011). Kaplan-Meier analysis revealed that event-free survival for cardiac events was significantly lower in the fQRS group than in the non-fQRS group (P = .036).

Conclusions: Our results demonstrated that the fQRS complex in patients with CAD with preserved LV ejection fraction was associated with subclinical global and regional LV dysfunctions as detected by 2-dimensional speckle-tracking imaging, and the results also predicted adverse cardiac events.

Publication types

  • Comparative Study
  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • China / epidemiology
  • Coronary Angiography
  • Coronary Artery Disease / complications
  • Coronary Artery Disease / diagnosis*
  • Coronary Artery Disease / mortality
  • Death, Sudden, Cardiac / epidemiology*
  • Death, Sudden, Cardiac / etiology
  • Diagnosis, Differential
  • Echocardiography / methods*
  • Electrocardiography / methods*
  • Female
  • Follow-Up Studies
  • Humans
  • Image Interpretation, Computer-Assisted*
  • Incidence
  • Male
  • Prognosis
  • Prospective Studies
  • Risk Assessment
  • Risk Factors
  • Stroke Volume
  • Survival Rate / trends
  • Ventricular Dysfunction, Left / complications
  • Ventricular Dysfunction, Left / diagnosis*
  • Ventricular Dysfunction, Left / mortality