Association between metabolic syndrome and fragmented QRS complexes: Speckle tracking echocardiography study

Metabolic syndrome (MetS) is an endocrinological disease with both metabolic and physiological components. Previous studies have shown a relationship between MetS and left ventricular (LV) dysfunction. A fragmented QRS (fQRS) is a reliable electrocardiogram (ECG) finding with the importance of an indicator of myocardial fibrosis and scarring. In this study, we examined the utility of speckle tracking echocardiography (STE) in assessing LV function in MetS patients with fQRS.

The 164 consecutive MetS patients included in the study. They were separated into two groups; those with (n=33) and those without (n=131) fQRS. The two groups were compared by obtaining LV strain values with STE.

Statistically significant differences between the fQRS (-) and fQRS (+) groups were identified for LV global longitudinal strain (LV-GLS) (p<0.001), maximum left atrial volume index (maxLAVI) (p≤0.001), strain rate during isovolumic relaxation period (SRivr) (p<0.001), and the E/SRivr ratio (p<0.001). In the multiple linear regression analysis, fQRS (β=-1.456, p=0.003), diabetes mellitus (β=-0.973, p=0.015), hypertension (β=-0.820, p=0.015) and MaxLAVI (β=-0.142, p=0.018) were independent predictors of LV-GLS. However, fQRS (β=21.995, p<0.001), MaxLAVI (β=3.090, p<0.001), and E/Em ratio (β=3.326, p<0.001) were also independent predictors of E/SRivr.

The results of this study showed that LV dysfunction was more common in MetS patients with fQRS. MetS patients, and especially those who are fQRS (+), should thus be closely monitored for subclinical LV systolic and diastolic dysfunction.