<prompt> Low QRS voltage on ECG indicates -Pulmonary embolismPericardial effusionCor pulmonaleInfective endocarditis  <response>: Ans. is b i.e., Pericardial effusion Ref: ECG Interpretation : From Pathyphysiology to clinical interpretation Springer2999- p. 281; 150 Practice ECG interpretation Review by Tavlor John Wiley Sons 2003-p. 48,491Causes of low voltage QRS complexeso Adrenal insufficiencyo Anasarcao Artifactual or spurious, eg, unrecognized standardization of ECG at one-half the usual gain i.e., 5 mmtnvo Cardiac infiltration or replacement e.g., amyloidosis, tumoro Cardiac transplantation, especially with acute or chronic rejectiono Cardiomyopathy, idiopathic or secondary?o Chronic obstructive pulmonary diseaseo Constrictive pericarditiso Hypothyroidism, usually with sinus bradycardiao Left pneumothorax mid-left chest leadso Myocardial infarction, extensiveo Myocarditis, acute or chronico Normal variano Obesityo Pericardial effusiono Pericardial tamponade, usually with sinus tachycardiao Pleural effusions 