Dipyridamole thallium scanning in the evaluation of coronary artery disease in elective abdominal aortic surgery
D. J. Strawn and J. M. Guernsey
Department of Surgery, Veterans Affairs Medical Center, Martinez, CA 94533.
Dipyridamole thallium scanning was routinely performed on 68 consecutive
patients who presented for elective aortic surgery. All 68 patients were
judged by clinical assessment to be at low risk for perioperative cardiac
complications. In addition, 42 of 68 patients had a history of myocardial
infarction, stable angina, or abnormal echocardiographic findings (group
1). Twenty-six of 68 patients did not have a history of myocardial
infarction, angina, or abnormal echocardiographic findings (group 2). In
group 1, 34 of 4 patients had positive results on dipyridamole thallium
scanning, and 15 of these patients were found to have critical coronary
artery disease on subsequent cardiac catheterization; nine underwent
immediate coronary artery bypass grafting, and six had their coronary
artery disease treated medically and their vascular operations cancelled.
The remaining 27 patients in group 1 underwent elective operations, with
six (22%) of 27 sustaining postoperative cardiac complications. None of the
group 2 patients was found to have critical coronary artery disease. All
patients in group 2 underwent aortic operation without cardiac
complication. Routine dipyridamole thallium scanning detected a 22% (15 of
68) incidence of critical coronary artery disease overall. There was a 36%
(15 of 42) incidence of critical coronary artery disease in group 1
patients vs 0% in group 2 patients (95% confidence interval, 21% to 50%).
We conclude that the use of dipyridamole thallium scanning in low-risk
patients for cardiac screening prior to elective aortic operations is
beneficial in selected patients who have a history of myocardial
infarction, angina, or abnormal echocardiographic findings, but is not
necessary in patients with no history of coronary artery disease.
