Role of Dual-Acquisition Noninvasive Cardiac CT Imaging for the Detection of Vasospastic Angina

Abstract

Background: Vasospastic angina (VSA) is characterized by chest pain at rest with transient ischemic electrocardiographic changes in the ST segment, and a prompt response to nitrates. Vasospastic angina is among the most frequent of the coronary artery diseases in Asia, and coronary computed tomography angiography (CCTA) may become available as a non-invasive diagnosis method. Methods: We prospectively enrolled 100 patients with suspected vasospastic angina at two centers from 2018 to 2020. All patients underwent baseline CCTA without a vasodilator in the early morning followed by catheterized coronary angiography and spasm testing. CCTA with intravenous infusion of nitrate (IV) was repeated within 2 weeks of baseline CCTA. Vasospastic angina as detected by CCTA was defined as significant stenosis (≥50%) with negative remodeling without definite plaques or diffuse small diameter (<2 mm) of a major coronary artery with a beaded appearance on baseline CT that completely dilated on IV nitrate CT. We analyzed diagnostic performance of dual-acquisition CCTA for the detection of vasospastic angina. Results: The patients were categorized into three groups according to their provocation test result (negative, n = 36; probable positive, n = 18; positive, n = 31). The diagnostic accuracy in terms of CCTA per patient had a sensitivity of 55% (95% CI, 40–69), specificity of 89% (95% CI, 74–97), positive predictive value (PPV) of 87% (95% CI, 72–95), and negative predictive value (NPV) of 59% (95% CI, 51–67). Conclusions: Dual-acquisition CCTA can support the non-invasive detection of vasospastic angina with relatively good specificity and PPV. CCTA was helpful for non-invasive screening of variant angina.

Which Coronary Artery Should Be Preferred for Starting the Coronary Spasm Provocation Test?

“…A large study using ergonovine stress echocardiography found 43% of wall motion abnormalities to be in the LAD region [22]. Jin et al reported a higher frequency of positive coronary spasms for the LAD (64.3%) in probable positive definition and the RCA (65.4%) in positive definition, albeit in a few cases [23]. In our study, the frequency of coronary spasms in the LAD was clearly higher.…”

“…In any case, if the involvement of the LCX Life 2023, 13, 2072 9 of 12 in coronary spasms is to be clarified, the SPT may be started from the LCA. Furthermore, the frequency of coronary spasms in the LAD and RCA also varied between reports [21][22][23]; Sueda et al [21] reported no difference in the positivity rate between the RCA (73.3%) and LAD (72%). A large study using ergonovine stress echocardiography found 43% of wall motion abnormalities to be in the LAD region [22].…”