Study On The Distribution Of Fragmented QRS Complex In Different Populations And Their Association With Ventricular Arrhythmia

Part1: Study on the distribution characteristics and clinical significance of Fragmented QRS complex in the middle and oldaged peopleObjective: To investigate the prevalence and clinical significance of fragmented QRS complexes(f QRS) in subjects of elderly population.Methods:The examination results of 759 normal subjects(aged 40-80 years)selected randomly were used as the research sample. Clinical data were collected including ECG, blood pressure, chest X-ray, blood lipid, blood glucose, etc. According to the presence or absence of f QRS, the cases were divided into two groups. The clinical data were compared, and univariate and multivariate logistic regression analyses were performed for f QRS.Results:1. A total of 751 cases were selected, and the mean age of the subjects was 51.86±8.88(40-80)years, including 486 males(64.71%) and 265 females(35.29%). The number of f QRS group was 120(15.98%), and 631(84.02%) of non-f QRS group. The detection rate of f QRS in males is higher than that in females(χ2=4.512, p<0.05). Compared with non-f QRS group, the age is older,systolic and diastolic blood pressure is higher, QRS axis is smaller in f QRS group(p<0.01). There were more cases whose cardiothoracic ratio were greater than 0.5 for X-ray check in f QRS group(20.00%) than that in non-f QRS group(2.69%)(χ2= 58.505, p<0.000).2. The detection rate of f QRS is different in different age group, and it increased with age(χ2=17.804, p<0.001).3. The incidence of f QRS on inferior wall, anterior wall and lateral wall was 13.38%, 2.59% and 2.07% respectively. There were significant differences among the three(χ2=118.252, p<0.001).4. In univariate and multivariate logistic regression analysis, systolic blood pressure, cardiothoracic ratio and QRS axis were independently associated with f QRS(p<0.05).Conclusions:1. There are differences in age, gender and location in the distribution of f QRS wave, which is more likely to be seen in aged males and more significant in inferior wall lead ECG.2. The generation of f QRS wave may be closely related to ventricular hypertrophy and cardiac enlargement caused by hypertension and other diseases.Part2: Study on the distribution of Fragmented QRS complexin hypertensive patients and its correlation with ventriculararrhythmiasObjective: To provide some guidance and reference for the prediction and prevention of malignant ventricular death, MVA and sudden cardiac death SCD through the retrospective study of the 12-lead ECG and other clinical data of 312 cases of hypertensive patients. The fragmented QRS(f QRS) wave distribution in patients with essential hypertension(EH) and related factors and correlation with ventricular arrhythmia were studied.Methods: A total of 414 patients with hypertension were randomly chosen in our hospital from July 2012 to July 2015. Clinical data were collected and divided into f QRS group and non-f QRS group according to the results of ECG. The clinical data were compared, and univariate and multivariate logistic regression analyses were performed for f QRS. According to the results of routine 12-lead electrocardiogram, 24-hour amulbatory electrocardiogram and ECG monitoring, analyses were performed for the relationship of f QRS and ventricular arrhythmia(inculuding Lown classⅢ~Ⅴpremature ventricular contractions, sustained ventricular tachycardia and ventricular fibrillation).Results:1. A total of 414 patients were recruited(f QRS group n=246; non-f QRS group n=168). Baseline clinical charateristics were compared between the two groups. The diameter of left ventricular, right ventricular, left atrium, right atrium and the thickness of left ventricular free wall in f QRS group weregreater than that in non-f QRS group(p<0.05). The left ventricular ejection fraction(LVEF) and QRS axis in f QRS group were smaller(p<0.05).2. In univariate and multivariate logistic regression analysis, the thickness of left ventricular free wall, right ventricular and QRS axis were independently associated with f QRS(p<0.05).3. The incidence of ventricular arrhythmia in f QRS group was obviously higher than that in non-f QRS group(χ2=9.847, p=0.002). Univariate and multivariate logistic regression analysis showed that f QRS is an independent risk factors of ventricular arrhythmia in patients with hypertension(p<0.05),on the other hand, other indicators including QT interphase(QTc), age, gender,diameter of left ventricular and right ventricular were independently related to ventricular arrhythmia(p<0.05).Conclusions:FQRS wave has a significant correlation with the occurrence of ventricular arrhythmia, and it is an independent risk factor of ventricular arrhythmias, which can be used as an indicator to identify patients with high risk of hypertension. The risk of f QRS wave may be related to the location of QRS wave masses, and the f QRS wave in the late stage of QRS wave may have a stronger effect on arrhythmia.