Characteristics of Circadian Blood Pressure Pattern of Hypertensive Patients According to Localization of Fragmented QRS on Electrocardiography

Introduction A narrow fragmented QRS complex (fQRS) indicates myocardial fibrosis and hypertensive cardiomyopathy in hypertensive patients. However, no study has investigated the importance of localization of fQRS on electrocardiography (ECG) in these subjects. Aim To investigate the association between circadian blood pressure (BP) pattern and localization of fQRS on ECG. Methods A total of 291 hypertensive patients who had fQRS in anterior or inferior leads were included into the study. Patients were divided into two groups according to localization of fQRS in inferior or anterior leads. All patients underwent a 24-h ambulatory blood pressure monitoring for detailed evaluation of circadian BP pattern. The association between localization of fQRS and non-dipping was investigated. Results Among study population, 182 (62.5%) patients had fQRS in inferior leads and 109 (37.5%) patients had fQRS in anterior leads. The frequency of patients with non-dipping BP pattern was significantly higher in patients with fQRS in anterior leads compared to patients with fQRS in inferior leads (47.7% vs 24.1%, p < 0.001). Moreover, the frequency of fQRS in anterior leads was significantly higher in non-dippers compared to dippers (64.6% vs. 24.1%, p < 0.001). Furthermore, in multivariate analysis, presence of fQRS in anterior leads was found to be an independent predictor of non-dipping BP pattern in hypertensive patients (OR: 1.748, 95% CI 1.362-2.446, p < 0.001). Conclusions Presence of fQRS in anterior leads is significantly associated with non-dipping BP pattern in hypertensive patients. Therefore, localization of fQRS on ECG may provide useful information regarding further risk assessment of hypertensive subjects.