Right-sided EKG in pulmonary embolism.

PURPOSE

To identify right-sided chest lead electrocardiographic abnormalities in acute pulmonary embolism.

PATIENTS AND METHODS

Analysis of electrocardiographic changes in 100 African American patients suspected of having pulmonary embolism was made at Howard University Hospital during 2001-02 (60% women, 40% men, median age 50 years). Standard 12-lead EKGs were obtained within one hour of arrival to emergency room. Right-sided EKGs were obtained within 24 hours of onset of symptoms of pulmonary embolism. Parameters of both right- and left-sided EKGs available were measured and compared.

RESULTS

Only 20% of these patients were diagnosed with pulmonary embolism. EKG changes (three of seven) suggestive of acute right ventricular strain were found in both right- and left-sided leads in 16 (80%) patients diagnosed with pulmonary embolism. These EKG changes disappeared within 24 hours of admission in 14 (87.5%) patients. Four patients with a diagnosis of pulmonary embolism had normal left-sided EKGs but the right-sided EKGs showed ST segment elevation and a qr or qs pattern (prominent q waves) in one to three of the leads V4R, V5R and V6R. These patterns were also seen in 10 of the 16 patients showing right ventricular strain pattern in their EKGs. Non-specific ST-T wave changes were seen in 20 (25%) patients not considered to have pulmonary embolism. V3R leads showed rS configuration in 90% of the patients.

CONCLUSION

EKG changes in right-sided chest leads occur frequently in pulmonary embolism. The diagnostic potential of routinely recorded right-sided EKG appears to be greatest in patients with acute pulmonary embolism not manifesting typical changes in their standard 12-lead EKGs. This study also confirms previous case reports observing similar changes in the right-sided leads.