A 62 years old man with carcinoma of lung presented to emergency depament with respiratory distress. His EKG showed electrical alternans. The most likely diagnosis is :
Answer is C (Cardiac tamponade): Electrical alternans refers to a beat-to-beat alteration in one or more components of the ECG signal. Total electrical alternans (P-QRS-T) with sinus tachycardia is a relatively specific sign for pericardial effusion, often with cardiac tamponade. - Harrison /5'4/1270 Feature Cardiac Tamponade Constrictive Pericarditis Restrictive Cardiomyopathy RVMI Electrical Alternans May he present Absent Absent Absent Note: Pleural effusion and pneumothorax both are potential complications of carcinoma lung that present with respiratory distress but electrical alternans is not associated.
Pneumothorax
Pleural effusion
Cardiac tamponade
Constrictive pericarditis.