Electrocardiographic abnormalities in patients with heart failure

BACKGROUND The morbidity and mortality from heart failure (HF) differ between patients with reduced (< 50%) and with preserved ( >or= 50%) left ventricular ejection fraction (LVEF) on account of many factors, including abnormalities detected in the electrocardiogram (ECG). The aim of this study was to determine and compare the ECG abnormalities between HF patients with reduced and with preserved LVEF. METHODS The study was cross-sectional in design and carried out in Aminu Kano teaching hospital and Murtala Mohammed specialist hospital, Kano, Nigeria, from April 2005 to June 2006. We studied the resting electrocardiograms of all HF patients aged 15 years and older who were referred to the two centres for echocardiography. RESULTS A total of 113 patients were studied and 98.2% of them had abnormal ECGs. Forty-two patients (37.2%) had preserved LVEF while the remaining 71 (62.8%) had reduced LVEF. Left ventricular hypertrophy (LVH) was the commonest ECG abnormality, found among 55 patients (77.5%) with reduced LVEF, and 21 patients (50%) with preserved LVEF (p = 0.0026). The commonest arrhythmia was atrial fibrillation, found among 10 patients (14.1%) with reduced LVEF and eight patients (19.1%) with preserved LVEF (p = 0.486). Prolonged corrected QT interval was found among 30 (71.4%) and 56 patients (78.9%) with preserved and reduced LVEF, respectively (p 5 0.370). CONCLUSION Most of the patients with heart failure studied in Kano, Nigeria had abnormal electrocardiograms, and the most common abnormality was LVH.