Fragmented QRS complexes are associated with left ventricular systolic and diastolic dysfunctions in patients with metabolic syndrome

BACKGROUND: Metabolic syndrome (MetS) is found to be associated with deterioration of the left ventricular (LV) systolic and diastolic functions. One of the factors for this impairment is myocardial fibrosis. Fragmented QRS (fQRS) complexes are found to be associated with myocardial fibrosis. The aim of the study was to evaluate if the presence of fQRS on electrocardiogram (ECG) can detect pronounced impairment in the LV systolic and diastolic functions in MetS patients. METHODS: The study included 111 (mean age 47 ± 9, 49.5% male) MetS patients and 96 (mean age 45 ± 9, 58.3% male) control subjects without MetS. ECG was evaluated for the presence of fQRS. Each patient underwent conventional echocardiography and tissue Doppler imaging. RESULTS: Fragmented QRS was more common among MetS patients (26.1% vs. 14.6%, p = 0.041). MetS was associated with subclinical LV systolic and LV diastolic dysfunctions. In subgroup analyses of MetS patients, the presence of fQRS on ECG had a higher E/E' ratio and lower E' velocity, indicating pronounced diastolic dysfunction, as well as lower isovolumic acceleration(IVA), indicating profound subclinical LV systolic dysfunction. E/E' ratio and IVA were independent predictors of fQRS presence in patients with MetS. CONCLUSIONS: Fragmented QRS is more common among MetS patients compared to non-MetS patients. The presence of fQRS is associated with pronounced subclinical LV systolic and diastolic dysfunctions in MetS patients.