title: Electrocardiographic pseudo-infarction pattern: appearance with a large posterior pericardial effusion after cardiac surgery.
abstract: Two patients with a large posterior pericardial effusion after cardiac surgery presented with electrocardiographic precordial Q waves without evidence of myocardial infarction. Resolution of the pericardial fluid resulted in the disappearance of the Q waves. Changes in conductivity and orientation of the heart within the pericardial space, along with a decrease in QRS voltage, could lead to the loss of initial R waves in the precordial leads, eventually resulting in a QS complex. Care should be taken in interpreting the electrocardiogram after cardiac surgery in patients with a large posterior pericardial effusion. The clinical course along with serial electrocardiographic and echocardiographic tracings should be helpful in identifying this false infarction pattern.
mesh_terms: D000328:Adult; D001022:Aortic Valve Insufficiency / Q000601:surgery; D001026:Coronary Artery Bypass; D003937:Diagnosis, Differential; D004452:Echocardiography; D004562:Electrocardiography; D006329:Heart Conduction System / Q000503:physiopathology*; D006350:Heart Valve Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000503:physiopathology; D010490:Pericardial Effusion / Q000175:diagnosis* / Q000503:physiopathology