Sinus tachycardia is common. ECG abnormalities may reflect the underlying coronary artery disease by way of pathological Q-waves, ST-T wave abnormalities. Left ventricular hypertrophy and left atrial enlargement show changes on ECG.
Atrial fibrillation with rapid ventricular rate may act as a precipitating factor for the heart failure or it may occur due to the underlying dilated cardiomyopathy. Ventricular ectopics are common in heart failure and may indicate adverse prognosis.
Left bundle branch block (LBBB) is usually associated with underlying heart disease. LBBB in coronary artery disease indicates severe disease, poor left ventricular function and decreased survival.