Potential value of thallium-201 scintigraphy as a means of selecting patients for the coronary care unit.

Abstract

The potential value of thallium-201 scintigraphy as a means of selecting patients for appropriate coronary care unit admission was evaluated. Studies were made prospectively on 203 patients with possible acute myocardial infarction but atypical history and non-diagnostic electrocardiogram at a time when the clinical diagnosis was still in doubt. Under conventional circumstances, this particular group of patients will be admitted to the coronary care unit for observation in order to rule out myocardial infarction by further clinical evaluation. Scintigraphy was performed upon arrival in the coronary care unit and within 10 hours after the last episode of chest pain. Of 203 patients, 49 had positive, 47 had questionable, and 107 had normal thallium-201 scintiscans. Serial serum enzyme determinations and further clinical follow-up disclosed acute myocardial infarction in 34 patients: all had abnormal scans. Of47 patients subsequently determined to present with unstable angina, 27 had abnormal scans, ofwhom 7 subsequently developed acute myocardial infarction. Of 24 patients with previous myocardial infarction, 18 patients had abnormal scans. None of either the 25 patients with stable angina or the 73 patients with atypical complaints showed frank perfusion defects, though questionable abnormal scintiscans were obtained in 5 and 12 patients in these groups, respectively.

The role of cardiovascular imaging techniques in the assessment of patients with acute chest pain

“…Initially, 201 Tl was used for rest MPI to identify patients with ACS. Wackers et al [7] performed planar 201 Tl imaging in 203 patients who presented with possible acute MI and was also found to have a high diagnostic accuracy. MPI was abnormal in all 34 patients with acute MI and abnormal in 27 of 47 (58%) patients with unstable angina.…”

Chest pain in the emergency department: role of cardiac imaging

“…The usefulness of rest MPI, with either technetium-99m-sestamibi or technetium-99m-tetrofosmin, in patients with acute chest pain for detecting ACS has been well validated 2 – 4. The unique strength of rest MPI is that images become abnormal at the very moment that regional myocardial blood flow is disturbed by an acute coronary narrowing (fig 3).…”

Myocardial perfusion imaging in the acute care setting: Does it still have a role?

“…Despite this 3 and other promising studies, 4 the use of acute thallium-201 MPI for evaluating chest pain patients was not adapted widely for various reasons. First, acute imaging with thallium-201 is logistically difficult.…”