A 14-year-old boy with a heart murmur was referred to the authors' department because structural heart disease could not be ruled out by standard echocardiographic views. The best apical four-chamber view was obtained with the patient turned to a right lateral decubitus position and the transducer shifted almost to the posterior axillary line. A biplane chest x-ray also showed a counterclockwise heart axis deviation. Magnetic resonance imaging confirmed the suspected congenital absence of the pericardium.