Dipyridamole Thallium Scanning in the Evaluation of Coronary Artery Disease in Elective Abdominal Aortic Surgery

Abstract

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.

Myocardial perfusion scintigraphy: the evidence

“… No. Inducible ischaemia (%) MI/death (%) PPV NPV Vascular surgery 1985 Boucher [ 135 ] 48 16 (33) 3 (6%) 19% (3/16) 100% (32/32) 1987 Cutler [ 136 ] 116 54 (47) 11 (10%) 20% (11/54) 100% (60/60) 1988 Fletcher [ 137 ] 67 15 (22) 3 (4%) 20% (3/15) 100% (56/56) 1988 Sachs [ 138 ] 46 14 (31) 2 (4%) 14%(2/14) 100% (24/24) 1989 Eagle [ 139 ] 200 82 (41) 15 (8%) 16% (13/82) 98% (61/62) 1990 McEnroe [ 140 ] 95 34 (36) 7 (7%) 9% (3/34) 96% (44/46) 1990 Younis [ 141 ] 111 40 (36) 8 (7%) 15% (6/40) 100% (51/51) 1991 Mangano [ 142 ] 60 22 (37) 3 (5%) 5% (1/22) 95% (19/20) 1991 Strawn [ 143 ] 68 n/a 4 (6%) n/a ...…”

Role of multimodality cardiac imaging in preoperative cardiovascular evaluation before noncardiac surgery

“…[15][16][17] These data also suggest that the increased risk is associated with higher segmental perfusion abnormalities.…”

Detection of perioperative myocardial ischaemia

“…Several other studies have confirmed the value of DTI in cardiac risk stratification [21,57,59,61,94,113,130]. Leppo and colleagues [57] found that, whilst exercise-induced ST-segment changes were not related to postoperative outcome, in patients who demonstrated thallium redistribution the risk of a postoperative cardiac event was 23 times greater than in patients without redistribution.…”

“…Cutler [22] Lette [59] Leppo [57] Younis [130] McEnroe [69] Levinson [63] Mangano [74] Lette [61] Reifsnyder [94] Eagle [29] Eagle [28] Strawn [113] Tischler [114] Lalka [56] Smith [111] Leung [62] London [66] Watters [126] Year 197719781991199119911991199319911991perioperative Year 198519911991199119911991 Type of surgery undergoing elective major non-cardiac surgery, but did not find it to be a predictor of postoperative outcome. It would seem from these studies that the exercise ECG is of limited value as a routine screening procedure for identifying at-risk patients, but that it may be of value for subgroups at greater risk of CAD, such as patients undergoing vascular surgery.…”