Beta blockers and the sensitivity of the thallium treadmill test.
The effect beta blockers (BB) may have on the sensitivity of the thallium treadmill test (Th-TMT) is controversial. The purpose of this study was to test the hypothesis that BB decrease the sensitivity of the Th-TMT. Two hundred three patients over a two-year period were identified who satisfied the following criteria. All had symptom-limited upright treadmill exercise tests with stress and redistribution thallium imaging, as well as coronary angiography within two months of the Th-TMT. Of 58 patients with CAD not on BB, 52 had an abnormal Th-TMT scan (sensitivity 90 percent). In comparison, the sensitivity of the Th-TMT scan in the 88 patients with CAD receiving BB was 76 percent (p less than 0.05). We conclude that BB may significantly decrease the sensitivity of the Th-TMT. Physicians should fully appreciate the higher false negative rate (24 vs 10 percent) for patients on BB and consider cautious withdrawal prior to diagnostic studies.
D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D003327:Coronary Disease / Q000000981:diagnostic imaging* / Q000188:drug therapy; D005080:Exercise Test; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D011868:Radioisotopes; D011877:Radionuclide Imaging; D013793:Thallium
D000319:Adrenergic beta-Antagonists; D011868:Radioisotopes; D013793:Thallium