Association of Fragmented QRS with Subclinical Left Ventricular Dysfunction in Patients with Obstructive Sleep Apnea


ADAR A., Kiris A., BÜLBÜL Y., Bektas H., Acat M., Casim H., ...More

MEDICAL PRINCIPLES AND PRACTICE, vol.24, no.4, pp.376-381, 2015 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 24 Issue: 4
  • Publication Date: 2015
  • Doi Number: 10.1159/000382077
  • Journal Name: MEDICAL PRINCIPLES AND PRACTICE
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.376-381
  • Keywords: Fragmented QRS, Obstructive sleep apnea, Left ventricular dysfunction, Myocardial fibrosis, CARDIAC MAGNETIC-RESONANCE, CORONARY-ARTERY-DISEASE, TEI-INDEX, 12-LEAD ECG, MECHANISMS, COMPLEXES, FIBROSIS
  • Karadeniz Technical University Affiliated: Yes

Abstract

Objective: We aimed to investigate whether fragmented QRS (fQRS) is associated with subclinical left ventricular (LV) dysfunction in patients with obstructive sleep apnea (OSA). Subjects and Methods: A total of 141 patients with OSA who had normal LV ejection fraction (LVEF) were included in the study. The fQRS was defined as the presence of an additional R wave, notching of R or S wave or the presence of fragmentation in 2 contiguous electrocardiography (ECG) leads. Subclinical LV dysfunction was defined as the presence of a tissue Doppler-derived Tei index of >= 0.5 in the absence of impaired LVEF (<50%) as assessed by transthoracic echocardiography. Results: Of the 141 patients, 71 (50.4%) had subclinical LV dysfunction. Overall, the prevalence of the fQRS was 61% (86/141). Patients with fQRS had significantly higher Tei indices than those without fQRS [median 0.66, interquartile range (IQR) 0.39 vs. median 0.40, IQR 0.15, p < 0.001]. The presence of fQRS on ECG predicted subclinical LV dys-function in univariate logistic regression analysis [odds ratio (OR) 6.69, 95% confidence interval (CI) 3.10-14.43]. The association remained significant after adjusting for all potential confounders (OR 4.59, 95% CI 1.94-10.87). Conclusion: fQRS on ECG was an independent predictor of subclinical LV dysfunction in patients with OSA. This simple tool might help to identify OSA patients who could be at risk for developing overt cardiac dysfunction. (C) 2015 S. Karger AG, Basel