Coronary Vasospasm Produces Reversible Perfusion Defects Observed During Adenosine Triphosphate Stress Myocardial Single‐photon Emission Computed Tomography

Abstract

Background: Adenosine triphosphate stress thallium-201 single-photon emission computed tomography (ATP-SPECT) is useful for diagnosing coronary artery disease (CAD), although sometimes false positive results are observed. It has not been established whether a coronary spasm is responsible for the false positive findings during ATP-SPECT. Hypothesis: We investigated whether coronary spasm is one of the factors which produces reversible defects on ATP-SPECT. Methods: Eighty-six patients (mean age: 62 y; 58 men) who underwent both spasm-provocation testing by coronary angiography and ATP-SPECT, were selected for the study. Patients with coronary narrowing (>30%), myocardial infarction, or heart failure were excluded. Patients were divided into 2 groups based on whether the spasm-provocation test result was positive (vasospastic angina [VSA] group, n = 46) or negative (non-VSA group, n = 39). Results: The body mass index was lower in the VSA group than in the non-VSA group (p = 0.005). On ATP-SPECT imaging, any type of reversible defect was observed more frequently in the VSA group (68%) than in the non-VSA group (36%, p = 0.0027). Logistic regression analysis demonstrated that the presence of reversible defects was one of the factors accounting for the presence of coronary vasospasm (p = 0.0022, R 2 = 0.172). Conclusions:The findings suggest that reversible defects on ATP-SPECT imaging are frequently present in patients with coronary vasospasm. Coronary spasm may be considered as 1 of the factors, which produce reversible defects on ATP-SPECT, observed in patients with chest symptoms and angiographically normal coronary arteries.

Atypical thymic carcinoid associated with coronary artery spasm: Incidental finding of myocardial perfusion imaging

“…Previous studies have observed that patients with vasospastic angina and angiographically normal coronary arteries can demonstrate reversible perfusion defects on stress MPI [5]. Coronary microvascular dysfunction, either mediated by endothelial dysfunction or impaired vascular smooth muscle [5], and may be an indicator of future development of atherosclerosis [6]. Thus in addition to noncritical atherosclerotic coronary lesions, it is likely that our patient was predisposed to coronary artery spasm because of the thymic carcinoid.…”

“…Moreover, coronary artery spasm had been reported to occur in arteries that lack histological evidence of atherosclerotic plaque [4]. Previous studies have observed that patients with vasospastic angina and angiographically normal coronary arteries can demonstrate reversible perfusion defects on stress MPI [5]. Coronary microvascular dysfunction, either mediated by endothelial dysfunction or impaired vascular smooth muscle…”

Clinical usefulness of myocardial scintigraphy in patients with vasospastic angina

“…As shown in Table 1, in 326 patients with VSA including 198 patients with exercise-Tl and 128 patients with pharmacologic stress-Tl, abnormal Tl findings were observed in 199 patients (61.0%), while sensitivity of Tl was 59.2% [15][16][17][18][19][20][21][22]. It was significantly lower than the sensitivity of BMIPP, as shown in Table 2.…”