Association between fragmented QRS complexes and left ventricular dysfunction in healthy smokers

Abstract

Objective Smoking is a known risk factor for cardiovascular diseases and may cause myocardial damage independently of coronary artery disease. Fragmented QRS (fQRS) is an important marker of myocardial fibrosis, while speckle‐tracking echocardiography is a method used to show subclinical left ventricle dysfunction. Methods Our study included 230 healthy individuals aged 18–40 years. The patients included were separated into two groups: those smokers (n = 130) and non‐smokers (n = 100). After that healthy smokers group were divided into two groups: those with fQRS (n = 24) and those without (n = 106). In both groups, the arithmetic mean of three images was used to obtain the left ventricle global longitudinal strain (LV‐GLS). The E/SRe ratio was also calculated and analyzed. Results There were significant differences between the smokers and non‐smokers in terms of, E/SRe (55.7 ± 17.9 vs 50.3 ± 14.8; P = 0.015), LV‐GLS (23.1 ± 1.9 vs 24.0 ± 1.7; P = 0.001), and fQRS (18.5% vs 6%; P = 0.005). As a result of subgroup analysis, pack‐year history was higher in the fQRS positive group (16.7 ± 3.7 vs 11.2 ± 3.7, P < 0.001). While a negative correlation was observed between pack‐year history and LV‐GLS (r = –0.678, P < 0.001), there was a positive correlation between pack‐year history and E/SRe (r = 0.730, P < 0.001). Conclusion In conclusion, our study demonstrated that fQRS is a parameter that can be used to determine left ventricle subclinical systolic and diastolic dysfunction in smokers, and that left ventricle dysfunction is related to the duration and intensity of smoking.

The effect of smoking on atrial and ventricular functions in healthy subjects: A speckle tracking echocardiography study

“…In a recent study, a negative correlation was observed between pack‐year history and LV GLS 19 . Interestingly, we did not find a correlation between the amounts of cigarettes smoked and strain variables.…”

Fragmented QRS as an early predictor of left ventricular systolic dysfunction in healthy individuals: a nested case-control study in the era of speckle tracking echocardiography

“…The association of mortality with GLS was stronger than LVEF [37]. GLS, which is obtained by STE, measures myocardial deformations via tracing of speckles' displacement [5,16,38]. Reduction in absolute GLS value is an indicator of a myocardial disease in most cases and portends future adverse events [35].…”

“…Less than two decades ago, fragmentation of QRS complex (fQRS) was coined on 12-lead EKG [ 3 ]. Abnormal deflections in QRS morphology is simply known as fQRS which originates from conduction delay and disrupted ventricular depolarization due to myocardial scarring [ 4 , 5 ]. fQRS is found in several cardiovascular and non-cardiovascular disorders including structural heart diseases [ 6 – 8 ].…”

Fragmented QRS as an early predictor of left ventricular systolic dysfunction in healthy individuals: A nested case-control study in the era of speckle tracking echocardiography

“…The association of mortality with GLS was stronger than LVEF (38). GLS, which is obtained by STE, measures myocardial deformations via tracing of speckles' displacement (5,16,39). Reduction in absolute GLS value is an indicator of a myocardial disease in most cases and portends future adverse events (36).…”

“…Abnormal de ections in QRS morphology is simply known as fQRS which originates from conduction delay and disrupted ventricular depolarization due to myocardial scarring (4,5). fQRS is found in several cardiovascular and non-cardiovascular disorders including structural heart diseases (6)(7)(8).…”