Tomographic thallium-201 myocardial perfusion imaging after intravenous dipyridamole in asymptomatic subjects with quadriplegia

Cardiovascular disease is the leading cause of mortality in those with a spinal cord injury (SCI). As a consequence of changes in body composition and level of activity, individuals with a SCI tend to have a high prelevance of multiple risk factors for coronary artery disease (CAD). In this report, we have demonstrated the usefulness of tomographic thallium-201 myocardial perfusion imaging after intravenous dipyridamole in six clinically asymptomatic subjects with quadriplegia. The average age of the subjects was 47 ± 2 years, and they had a duration of injury of 15 ± 2 years. On average, the individuals had five risk factors for CAD. After intravenous administration of dipyridamole and mild upper extremity exercise, the subjects reported no adverse symptoms and had no electrocardiographic evidence suggestive of ischemia. By contrast, three of the six subjects had reversible defects noted on thallium scintigraphy, and one additional subject had a fixed defect that was suggestive of infarction. The remaining two subjects had abnormal scans with fixed defects of the inferioposterior region, which may be ascribed to diaphragmatic attenuation, perhaps a result of partial diaphragmatic paralysis. Thus, dipyridamole thallium myocardial imaging is a safe and effective noninvasive method for the detection of myocardial ischemia or infarction in individuals with quadriplegia who are at increased risk for CAD.