The effect of circadian blood pressure pattern on presence of fragmented QRS complexes in hypertensive subjects.

The association of deteriorated circadian blood pressure (BP) variability with presence of fragmented QRS (fQRS) on electrocardiography (ECG) is not clear. The present study aims to evaluate the relationship of BP patterns with presence of fQRS on ECG. A total of 338 consecutive newly diagnosed and never treated hypertensive patients who are without left ventricular hypertrophy and underwent 24-hour ambulatory BP monitoring were enrolled. Patients were classified as dippers, nondippers, and reverse dippers according to ambulatory BP monitoring results. The groups were compared regarding frequency of fQRS on ECG. The frequency of fQRS was significantly higher in reverse dippers compared with dippers (37.7% vs. 20.6%, P = .013). In multivariate logistic regression analysis, nighttime systolic BP was found to be an independent predictor of fQRS on ECG (P < .001, 95% confidence interval = 0.901-0.955). Other predictors of fQRS were daytime diastolic BP and age. Furthermore, fQRS was found to be an independent predictor of reverse dipping BP pattern in hypertensive patients (P = .004, odds ratio: 2.416, 95% confidence interval = 1.327-4.396). In conclusion, as a marker of fibrosis and higher fibrotic burden within myocardium, fQRS may be useful to determine the high-risk hypertensive patients in the absence of left ventricular hypertrophy.