bACKgRoUND: Fragmented QRS (fQRS), QT prolongation and wide QRS have been associated with increased risk for cardiac arrhythmias. objECTIVES: To describe the prevalence and correlates among Nigerians with heart failure. METhoDS: A total of 129 subjects were consecutively recruited for the present study. QT interval, QRS duration and fQRS were determined. SPSS version 16 was used for analysis. R...

This paper presents a novel algorithm to detect onset and duration of QRS complexes. After low-pass filtering, the ECG signal is converted to a curve length signal by a transform in which a nonlinear scaling factor is introduced to enhance the QRS complex and to suppress unwanted noise. Adoptive thresholds are applied to the length signal to determine the onset and duration of the QRS complex. ...

BACKGROUND Cardiac resynchronization therapy (CRT) is effective in reducing clinical events in patients with heart failure and prolonged QRS interval. Studies using surrogate measures and subgroup analysis of large trials suggest that only patients with severely prolonged QRS benefit from CRT. Our objective was to determine whether the effect of CRT on adverse clinical events (eg, death, hospit...

Numerous parameters are associated with a dismal prognosis in heart failure patients. Some of these factors may be mechanistically related, such as increased left ventricular (LV) volume, functional mitral regurgitation (MR), QRS widening, and LV dyssynchrony. Indeed, LV dilation produces distortion of ventricular geometry. The apical and outward displacement of the mitral leaflets restricts th...

BACKGROUND Although fragmented QRS complex (frag-QRS) reflecting intra-ventricular conduction delay has been shown to be a prognostic marker for cardiac events, few data exist regarding the impact of frag-QRS on cardiac events in hypertrophic cardiomyopathy (HCM). METHODS AND RESULTS Ninety-four HCM patients (56 male; mean age, 58 ± 17 years) were retrospectively investigated. Frag-QRS was de...

BACKGROUND Cardiac resynchronization therapy (CRT) decreases mortality, improves functional status, and induces reverse left ventricular remodeling in selected populations with heart failure. We aimed to assess the impact of baseline QRS duration and morphology and the change in QRS duration with pacing on CRT outcomes in mild heart failure. METHODS AND RESULTS Resynchronization Reverses Remo...

BACKGROUND Distortion of the terminal portion of the QRS in the initial electrocardiogram (ECG) is a strong predictor of adverse outcome in myocardial infarction. Our purpose is to assess the relationship of distortion of QRS and other ECG characteristics with older age. METHODS AND RESULTS We analysed 634 consecutive patients (age 62.6 +/- 13.7, 77% male) admitted in the first 12 hours of ST...

BACKGROUND Left ventricular (LV) dyssynchrony is a prevalent feature in heart failure (HF) patients. The current study aimed to evaluate the prevalence of inter and intraventricular dyssynchrony in HF patients with regard to the QRS duration and etiology. METHODS The available data on the tissue Doppler imaging (TDI) of 230 patients with refractory HF were analyzed. The patients were divided ...

BACKGROUND Prolonged QRS duration is associated with increased mortality among heart failure patients, but race or sex differences in QRS duration and associated effect on outcomes are unknown. METHODS AND RESULTS We investigated QRS duration and morphology among 2463 black and white patients with heart failure and left ventricular ejection fraction ≤35% who underwent coronary angiography and...

BACKGROUND Citalopram is a selective serotonin reuptake inhibitor that requires routine cardiac monitoring to prevent a toxic dose. Prolongation of the QT interval has been observed in acute citalopram poisoning. Our previous experimental study showed that citalopram may be lead to QT prolongation by stimulating adenosine A1 receptors without affecting the release of adenosine. AIMS We examin...