The Declining Specificity of Exercise Radionuclide Ventriculography

Abstract

Although exercise radionuclide ventriculography was initially reported to be a highly specific test for coronary-artery disease, later studies reported a high false-positive rate. To verify this turnabout, we analyzed the responses in 77 angiographically normal patients; 32 were studied from 1978 to 1979 (the early period), and 45 from 1980 to 1982 (the recent period). Most patients studied in the early period had normal responses (94 per cent for ejection fraction and 84 per cent for wall motion). In contrast, normal responses were less frequent in patients studied in the recent period (49 per cent for ejection fraction and 36 per cent for wall motion, P less than 0.001). The probability of coronary disease before testing was higher in these patients (38 vs. 7 per cent, P less than 0.001). More patients studied in the recent period underwent radionuclide ventriculography before angiography (78 vs. 22 per cent, P less than 0.001), and more of these prior studies had abnormal results than those performed after angiography (55 vs. 6 per cent, P less than 0.0001). Thus, two factors are responsible for the temporal decline in specificity: a change in the population being tested (pretest referral bias) and a preferential selection of patients with a positive test response for coronary angiography (post-test referral bias).

Single-day combined evaluation of regional myocardial perfusion and function at rest and peak exercise with99mTc-MIBI in patients with coronary artery disease

“…In our study group, functional images confirmed the results obtained in previous investigations [19,20,23,28], proving to be very sensitive in the detection of both CAD patients (98%) and pathological coronary regions (94%). As expected, specificity was lower, as false positive results were found in 20% of normal subjects and in 40% of normal coronary regions.…”

Nuclear myocardial perfusion imaging with a novel cadmium-zinc-telluride detector SPECT/CT device: first validation versus invasive coronary angiography

“…On the other hand, however, the data for specificity and NPV are much less solid due to the well-known referral bias as a consequence of the awareness of SPECT MPI to rule out CAD as a reliable gate-keeper for invasive coronary angiography [11]. Thus, patients without ischemia in MPI are generally not referred to invasive coronary angiography reducing the number of true negative MPI findings leading to a decline in specificity overtime [13]. In addition, the relatively high prevalence of CAD in our study may have contributed to the modest NPV.…”

Heart rate adjustment of ST segment depression for improved detection of coronary artery disease.

“…31 Using a limited number of electrocardiographic leads in a retrospective evaluation of catheterized patients with only a 46% prevalence of coronary disease, Detrano et a120 found a modified AST/HR index to have a specificity of approximately 80%, when interpolated data from their naiy disease.30 report are examined at an estimated partition value of 1.6 prV/beats/min. This result falls between the high specificity found in our subjects with a low likelihood of disease and the lesser specificity found in our highly preselected patients with angina but normal coronary angiograms.…”