A 61-year-old man with treated hypertension and a history of excessive alcohol intake was referred for echocardiography to rule out cardiomyopathy. He had a history of a heart murmur for 29 years and had the recent onset of shortness of breath on exertion. Results of the clinical evaluation were initially remarkable for an S4 gallop and cardiac enlargement on chest x-ray film. A routine M-mode echocardiogram was abnormal, leading to the performance of a contrast echocardiogram by rapid-bolus hand injection of 10 mL of 5% dextrose into a peripheral vein. Figure 1 is an M-mode tracing after this injection.
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Fig 1.—M-mode echocardiogram. Right ventricular (RV) dimension (45 mm) is increased and there is paradoxical motion of ventricular septum (VS) relative to posterior wall (PW). Contrast effect after peripheral vein injection of dextrose appears in RV (large arrowhead). Small number of contrast echoes in left ventricle